Question: Who was the composer of the film “Roman Holiday”?

Roman holidays

The recitative and the beginnings of the lines bring the translation closer not to Shelley's original, but to Shelley's “Arethusa” set to new measures”, written by beat generation poet Robert Duncan:


Question: Who was the composer of the film “Roman Holiday”?

Roman holidays

“Now Arethusa from her snow couches arises,”


Question: Who was the composer of the film “Roman Holiday”?

Roman holidays

Duncan's poem, however, was officially published only in 1964, in his collection Roots and Branches [24].


Question: Who was the composer of the film “Roman Holiday”?

Roman holidays

Cultural influence and symbolism of the film


Question: Who was the composer of the film “Roman Holiday”?

Roman holidays

From the memoirs of the direct participants in the creation of the film, it follows that everything developed for objective circumstances and practical reasons.


Question: Who was the composer of the film “Roman Holiday”?

Roman holidays

William Wyler took over the script because it was abandoned by another director.


Question: Who was the composer of the film “Roman Holiday”?

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Europe was chosen to use the company's frozen accounts, have free city views and inexpensive extras.


Question: Who was the composer of the film “Roman Holiday”?

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In addition, quite a long work abroad exempted actors from paying tax in the United States.


Question: Who was the composer of the film “Roman Holiday”?

Roman holidays

However, literary critics and critics see deeper meanings in the chain of events.


Question: Who was the composer of the film “Roman Holiday”?

Roman holidays

Peter Kramer considers “Roman Holiday” one of the cultural factors in the formation of a united Europe: with its mixture of cultures of different countries and the removal of the mystical halo from royals — where Hollywood is free or unwittingly acted as a trendsetter and habits of a new generation of Europeans.


Question: Who was the composer of the film “Roman Holiday”?

Roman holidays

The very choice of Europe and Rome is associated with the personality of director William Wyler.


Question: Who was the composer of the film “Roman Holiday”?

Roman holidays

Being certainly a Hollywood director at his place of work and place of resounding success, Wyler was nevertheless born and spent his young years in Muehlhausen, then part of Alsace-Lorraine.


Question: Who was the composer of the film “Roman Holiday”?

Roman holidays

During the Second World War, he returned to Europe as a military film journalist.


Question: Who was the composer of the film “Roman Holiday”?

Roman holidays

And his desire to leave the atmosphere of McCarthyism for a while and return to Europe again is understandable.


Question: Who was the composer of the film “Roman Holiday”?

Roman holidays

Of course, the researcher also sees Audrey Hepburn as a European integration figure.


Question: Who was the composer of the film “Roman Holiday”?

Roman holidays

With the advent of fame, some critics declared her Dutch, others Englishwoman, some pointed to the naturalness of her behavior, others to aristocratic roots — and each was in his own right [25].


Question: Who was the composer of the film “Roman Holiday”?

Roman holidays

Rental and releases


Question: Who was the composer of the film “Roman Holiday”?

Roman holidays

General information


Question: Who was the composer of the film “Roman Holiday”?

Roman holidays

It premiered on August 27, 1953 in New York, at Radio City Music Hall.


Question: Who was the composer of the film “Roman Holiday”?

Roman holidays

The film was released in Italy on February 25, 1954, and was shown in many European countries at various times in the same year.


Question: Who was the composer of the film “Roman Holiday”?

Roman holidays

The film had a huge and unexpected success in Japan.


Question: Who was the composer of the film “Roman Holiday”?

Roman holidays

The younger generation of Japanese women at this time was just thinking about leaving the patriarchal framework of the life of a Japanese woman, and Hepburn's character became a role model for them, right down to appearance.


Question: Who was the composer of the film “Roman Holiday”?

Roman holidays

And many years later, during a tour of Japan, William Wyler was surprised at the mass of Japanese women with Princess Anna hairstyles [7].


Question: Who was the composer of the film “Roman Holiday”?

Roman holidays

In the USSR, the film was dubbed by the film studio.


Question: Who was the composer of the film “Roman Holiday”?

Roman holidays

Gorky was released only in July 1960, almost seven years after the world premiere [26].


Question: Who was the composer of the film “Roman Holiday”?

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“Paramount Home Video” was first released for home viewing in 1976 on Betamax and VHS videotapes.


Question: Who was the composer of the film “Roman Holiday”?

Roman holidays

In 2002, a special DVD Collector's Edition was released in the United States.


Question: Who was the composer of the film “Roman Holiday”?

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The film has been fully restored.


Question: Who was the composer of the film “Roman Holiday”?

Roman holidays

In addition, there was a documentary “Remembering the Roman Holiday”, with interviews with the participants and creators alive at the time, as well as their children.


Question: Who was the composer of the film “Roman Holiday”?

Roman holidays

In foreign language versions, including Russian, the film mainly retained its original title translated into the corresponding language.


Question: Who was the composer of the film “Roman Holiday”?

Roman holidays

But there are exceptions.


Question: Who was the composer of the film “Roman Holiday”?

Roman holidays

For example, in German-speaking countries, the film is called “Heart and Crown” (German: Ein Herz und eine Krone), and in Spanish-speaking Latin American countries (but not Spain), the film is somewhat pessimistically named” The princess who wanted to live”


Question: Who was the composer of the film “Roman Holiday”?

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(Spanish: La princesa que quería vivir).


Question: Who was the composer of the film “Roman Holiday”?

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Worldwide rental


Question: Who was the composer of the film “Roman Holiday”?

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Despite the rain of awards for the main singer and excellent press, “Roman Holiday” did not become a blockbuster in the United States.


Question: Who was the composer of the film “Roman Holiday”?

Roman holidays

With the announced budget of $1.5 million for the first six months, the fees amounted to 3 million and 5 million for the entire period of the first rental.


Question: Who was the composer of the film “Roman Holiday”?

Roman holidays

This is quite modest for an Oscar-winning film.


Question: Who was the composer of the film “Roman Holiday”?

Roman holidays

Most of the fees ($7 million) came from foreign distribution, primarily from Europe, where Roman Holiday was at the time one of the most successful Hollywood films in history.


Question: Who was the composer of the film “Roman Holiday”?

Roman holidays

It was also a huge success in Japan, where the film became a cult for generations of Japanese women.


Question: Who was the composer of the film “Roman Holiday”?

Roman holidays

In total, $12 million was collected for the first release (8 times the budget).


Question: Who was the composer of the film “Roman Holiday”?

Roman holidays

This is not an extraordinary success, but by the standards of the 1950s it is quite a successful release [7] [27].


Question: Who was the composer of the film “Roman Holiday”?

Roman holidays

Features of rolled products in the USSR


Question: Who was the composer of the film “Roman Holiday”?

Roman holidays

In addition to the fact that the film was released 7 years after its premiere, it was censored in the USSR: when dubbed at the film studio.


Question: Who was the composer of the film “Roman Holiday”?

Roman holidays

Gorky was removed about 5 minutes of the film.


Question: Who was the composer of the film “Roman Holiday”?

Roman holidays

A specific list of deleted scenes has not been published anywhere, but on modern restored copies, they can be distinguished by the transition from duplication to voice-over.


Question: Who was the composer of the film “Roman Holiday”?

Roman holidays

Even in a censored form, the film caused concern of the Secretariat of the CPSU Central Committee, given the high popularity of “Roman Holidays” among Soviet moviegoers.


Question: Who was the composer of the film “Roman Holiday”?

Roman holidays

At a closed meeting of the Ideological Commission of the CPSU Central Committee following the results of 1960, it was pointed out that cinemas, in pursuit of attendance figures, too often show foreign films to the detriment of Soviet ones.


Question: Who was the composer of the film “Roman Holiday”?

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The Ideological Commission noted [28]:


Question: Who was the composer of the film “Roman Holiday”?

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As a result, American, English and French films that show the bourgeois lifestyle in an embellished light have been released in higher circulation.


Question: Who was the composer of the film “Roman Holiday”?

Roman holidays

Circulations of such bourgeois films imbued with ideas unacceptable to us as “Roman Holiday” — 1,157 copies, “12 Girls and One Man” — 1304 copies, “Mr. Pitkin Behind Enemy Lines” — 1350 copies, “Babette goes to war” — 1367 copies, exceeded the circulation <... >


Question: Who was the composer of the film “Roman Holiday”?

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The American film “Roman Holiday” was shown 40 times at only two major venues and was watched by 250,955 people.


Question: Who was the composer of the film “Roman Holiday”?

Roman holidays

Compared to other Western films, we can assume that “Roman Holiday” was held in the USSR intact [29].


Question: Who was the composer of the film “Roman Holiday”?

Roman holidays

In any case, neither the United States nor the USSR at that time were members of the Berne Convention and did not make mutual deductions for the screening of films, so directly to the financial indicators of Paramount Pictures success in the USSR did not affect.


Question: Who was the composer of the film “Roman Holiday”?

Roman holidays

Remakes


Question: Who was the composer of the film “Roman Holiday”?

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Cinematography


Question: Who was the composer of the film “Roman Holiday”?

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In 1987, Paramount Television's color television remake of the same name was released in the United States.


Question: Who was the composer of the film “Roman Holiday”?

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Catherine Oxenberg played the role of the princess (her name is Eliza, not Anna).


Question: Who was the composer of the film “Roman Holiday”?

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The role of Joe Bradley was played by Tom Conti.


Question: Who was the composer of the film “Roman Holiday”?

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This time the princess was played by a real person of royal blood: Catherine is the daughter of Princess Elizabeth from the Karageorgievich family.


Question: Who was the composer of the film “Roman Holiday”?

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The film received restrained ratings.


Question: Who was the composer of the film “Roman Holiday”?

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With almost verbatim following the original, it was shot in Lisbon or on artificial scenery, and not in Rome.


Question: Who was the composer of the film “Roman Holiday”?

Roman holidays

Joe Bradley now dreams not to “go to New York and start working for a real newspaper”, but to make enough money, quit his job and go to Corfu.


Question: Who was the composer of the film “Roman Holiday”?

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According to the critic, these and other details make the TV film neither a travelogue nor a film close to the original in emotionality [30].


Question: Who was the composer of the film “Roman Holiday”?

Roman holidays

Another critic refers the problems with remake attempts not to the actors' play or director's work, but to the changed world and perception of the audience:


Question: Who was the composer of the film “Roman Holiday”?

Roman holidays

In the early 1950s, it was still possible to believe in princesses under such strict control that they had no life of their own.


Question: Who was the composer of the film “Roman Holiday”?

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This stereotype is much less convincing in the era of Lady Di, Fergie, and Stephanie.


Question: Who was the composer of the film “Roman Holiday”?

Roman holidays

And when the princess performed by Oxenberg nicely asks how pizza is eaten, she does not look so much isolated from life as slightly slowed down in mental development [31].


Question: Who was the composer of the film “Roman Holiday”?

Roman holidays

In 2008, a remake film Kings Can Do Everything by NTV-Kino studio was released in Russia.


Question: Who was the composer of the film “Roman Holiday”?

Roman holidays

The film has been moved to St. Petersburg, where Princess Maria (Elena Polyakova) comes and where journalist Max Shalnov (Gosha Kutsenko) meets her.


Question: Who was the composer of the film “Roman Holiday”?

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As in the case of the American remake, the quality of the film was called incomparable to the original: neither in terms of plot disclosure nor in the actors' performance [32].


Question: Who was the composer of the film “Roman Holiday”?

Roman holidays

Sometimes the 1981 Italian comedy Madly in Love is also included in the remakes, although its story is about bus driver Cicchini (Adriano Celentano) and Princess Cristina from the tiny kingdom of San Tulip ( Ornella Muti) only in the most general terms resembles the “Roman Holiday”.


Question: Who was the composer of the film “Roman Holiday”?

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Theatre


Question: Who was the composer of the film “Roman Holiday”?

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In 2001, director Paul Blake directed the musical “Roman Holiday” based on the plot of the famous film.


Question: Who was the composer of the film “Roman Holiday”?

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For musical numbers, he used music and songs by Cole Porter (1891—1964), which he managed to fit well into the plot.


Question: Who was the composer of the film “Roman Holiday”?

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The musical includes such famous hits of past years as “Begin the Beguine”, “You'd be so easy to love”, “Ev'ry time we say goodbye”.


Question: Who was the composer of the film “Roman Holiday”?

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It premiered during the 2001 summer season at St.


Question: Who was the composer of the film “Roman Holiday”?

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Louis MUNY, an open-air stage in St. Louis.


Question: Who was the composer of the film “Roman Holiday”?

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The musical was then put on the shelf for a long time [33].


Question: Who was the composer of the film “Roman Holiday”?

Roman holidays

In 2012, the Guthrie Theater staged a new production of the same musical.


Question: Who was the composer of the film “Roman Holiday”?

Roman holidays

In the first productions, the princess is sung and played by Laura Osnes, then the part went to Stephanie Rotenberg [33].


Question: Who was the composer of the film “Roman Holiday”?

Roman holidays

Since its inception, the film has remained a cult in Japan.


Question: Who was the composer of the film “Roman Holiday”?

Roman holidays

Only new dubbed translations involving the best Japanese artists were made five times (1972, 1979, 1992, 1994, 2004).


Question: Who was the composer of the film “Roman Holiday”?

Roman holidays

Drama productions are also staged in theaters and the musical “Roman Holiday” (Japanese: Day), in which the Japanese idol Sayaka Akimoto successfully performed the role of Princess Anna in 2010-2012.


Question: Who was the composer of the film “Roman Holiday”?

Roman holidays

Copyrights


Question: Who was the composer of the film “Roman Holiday”?

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Initially, the rights to show belonged to Paramount Pictures.


Question: Who was the composer of the film “Roman Holiday”?

Roman holidays

In 1993, the company sold the exclusive rights to about 300 of its films, including Roman Holiday, to Ted Turner, and they are now owned by his Turner Classic Movies (TCM) channel.


Question: Who was the composer of the film “Roman Holiday”?

Roman holidays

The original 1953 English trailer is considered to be in the public domain, as it was published before 1978 (the year the laws were amended) and without registration in, and without a sign copyright.


Question: Who was the composer of the film “Roman Holiday”?

Roman holidays

In Japan, until 2004, copyright protection was 50 years.


Question: Who was the composer of the film “Roman Holiday”?

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It was expanded to 70 to harmonize with current world practice, but only for those works that remained under protection as of January 1, 2004.


Question: Who was the composer of the film “Roman Holiday”?

Roman holidays

As a result, a number of American films published in Japan in 1953 and earlier appeared in the public domain in this country.


Question: Who was the composer of the film “Roman Holiday”?

Roman holidays

This situation caused sharp protests from American companies and in 2007 reached the Supreme Court of Japan [35].


Question: Who was the composer of the film “Roman Holiday”?

Roman holidays

However, no final decisions were made for 2012, and the film “Roman Holiday” in Japan can be considered in the public domain [36].


Question: Who was the composer of the film “Roman Holiday”?

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Notes


Question: Who was the composer of the film “Roman Holiday”?

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Literature


Question: Who was the composer of the film “Roman Holiday”?

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Truffaut F. Hitchcock/Translation, filmography, notes by M. Yampolsky and N. Tsyrkun.


Question: Who was the composer of the film “Roman Holiday”?

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— M.: Eisenstein Center for Film Culture Research, 1996.


Question: Who was the composer of the film “Roman Holiday”?

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— 224 p.


Question: Who was the composer of the film “Roman Holiday”?

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Mussky I. A. 100 great foreign films.


Question: Who was the composer of the film “Roman Holiday”?

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— Moscow: Veche, 2008.


Question: Who was the composer of the film “Roman Holiday”?

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— 480 p. — ISBN 978-5-9533-2750-3.


Question: Who was the composer of the film “Roman Holiday”?

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References


Question: Who was the composer of the film “Roman Holiday”?

Roman holidays

on IMDb


Question: Who was the composer of the film “Roman Holiday”?

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at AllMovie


Question: Who was the composer of the film “Roman Holiday”?

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on YouTube (English, 1953)


Question: Who was the composer of the film “Roman Holiday”?

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Category: American comedy films


Question: Who was the composer of the film “Roman Holiday”?

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Category: Comedy films of 1953


Question: Who was the composer of the film “Roman Holiday”?

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Category:Films about journalists


Question: Who was the composer of the film “Roman Holiday”?

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Category:Movies about Rome


Question: Who was the composer of the film “Roman Holiday”?

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Category:National Film Registry


Question: Who was the composer of the film “Roman Holiday”?

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Category:Movies in English


Question: Who was the composer of the film “Roman Holiday”?

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Category: 1953 American films


Question: How is glass made?

glass

Glass is a substance and material, one of the oldest and, due to its variety of properties, is universal in human practice.


Question: How is glass made?

glass

Structurally amorphous, isotropic; all types of glasses during formation are converted in an aggregate state - from extreme viscosity of liquid to the so-called glassy - during cooling with a speed sufficient to prevent crystallization of melts obtained by melting the raw material (charge) [1] [2].


Question: How is glass made?

glass

The glass melting temperature, from +300 to +2500° C, is determined by the components of these glass-forming melts (oxides, fluorides, phosphates and others) [2].


Question: How is glass made?

glass

Transparency (for human visible radiation) is not a common property for all types of glasses that exist both in nature and in practice.


Question: How is glass made?

glass

Origin of the term


Question: How is glass made?

glass

The title of this material has different etymologies in different languages.


Question: How is glass made?

glass

Romance languages (Italian: vetro, French: verre, Spanish: vidrio, Portuguese: vidro) continue the Latin name (Latin: vitrum).


Question: How is glass made?

glass

The exception is the Romanian language (Romanian: sticlă), which borrowed the name of glass from Slavic ones.


Question: How is glass made?

glass

Latin vitrum comes from “light” (English: white) [3].


Question: How is glass made?

glass

Germanic languages inherited the word for glass (English: glass, German: Glas, Dutch, Danish, Swedish glas) from Proto-German: *glasan ~ glazan, derived from “shine, shine” [4].


Question: How is glass made?

glass

In Slavic (“glass”, Belarusian: shklo, Ukrainian: sklo; Church Slavonic: stklo, Bulgarian: glass, Macedonian: staklo, Serbo-Croatian: staklo, Slovenia: steklo; Czech: sklo, Slovak: sklo, Polish: — szkło) - apparently, a borrowing from Gothic: stikls (“cup”, “bowl”, “horn”, < pragerm. *stikkon - “stick, stab”, cf. English: stick, with the same value) [5] [6] [7] [8] [9] [10] [11].


Question: How is glass made?

glass

History of the term


Question: How is glass made?

glass

On the word of the Russian language by V. AND. Dahl said: “Glass cf., glass south west and crk., alloy sand (siliceous) with potash; chemical sodium silicate, sometimes potassium, lead oxide” [12].


Question: How is glass made?

glass

Old Slavyanskoe - stkle, stklyano - glass [sea] (Apocalypse - Rev.; Apok 15, 2); Old Russian (since the XI century) - stklo (neuter noun of the second type of declension - according to N. D. Rusinov) [13]; “steka — Pskov, Tver dialect” [12].


Question: How is glass made?

glass

Initially, glass was called only the well-known and most common glassmaking product, which for some time now has been attributed in scientific use to silicate glass.


Question: How is glass made?

glass

When the identity of the structure, composition and properties of glass to many minerals was established, the latter began to qualify as varieties of its natural counterpart, named in accordance with the conditions formations: non-crystallized derivatives of rapidly cooled lava — volcanic glass (pumice, obsidians, pechstein, basalts, etc.) formed from the earth's rock as a result of an impact cosmic body - meteorite (moldavite); a special class of glassy minerals is fulgurites (clastofulgurites), which are formed from silicate deposits (SiO2 - sand, quartz, silica - that is, trivial, the most common raw materials in ordinary glassmaking), as a result of a powerful lightning discharge, are found mainly on the tops of rocky mountains in areas with increased thunderstorm activity, translucent samples of clastofulgurites also occur.


Question: How is glass made?

glass

The main reason for the creation of a synthetic substitute, organic glass, was the lack of materials suitable for use in aviation at the time of its development (1930s).


Question: How is glass made?

glass

This polymer, respectively, belonging to the class of organic substances, is referred to as glass only by its external similarity: a transparent, sometimes colored substance.


Question: How is glass made?

glass

The history of glass (technology)


Question: How is glass made?

glass

For a long time, Egypt was recognized as the primacy in the discovery of glassmaking, to which glass-glazed faience tiles of the inner linings of the Josser pyramid (XXVII century BC) were considered undoubted evidence AD); an even earlier period (the first dynasty of the pharaohs) includes the findings of faience jewelry, that is, glass existed in Egypt already 5 thousand years ago.


Question: How is glass made?

glass

The archaeology of Ancient Mesopotamia, especially Ancient Sumer and Akkad, persuades researchers to believe that a monument found in Mesopotamia in Ashnunak district is a cylindrical transparent glass seal dating back to the period of the Akkad dynasty, that is, its age is about four and a half thousand years.


Question: How is glass made?

glass

The greenish bead with a diameter of about 9 mm, stored in the Berlin Museum, is considered one of the oldest examples of glassmaking.


Question: How is glass made?

glass

It was found by Egyptologist Flinders Petrie near Thebes, according to some ideas she is five and a half thousand years old.


Question: How is glass made?

glass

N. N. Kachalov notes that on the territory of the Starovavilonian Kingdom, archaeologists regularly find incense vessels of local origin, made in the same technique as the Egyptian ones.


Question: How is glass made?

glass

The scientist argues that there is every reason to believe that “in Egypt and Western Asia, the origins of glassmaking... are separated from the present day by an interval of about six thousand years” [14] [15].


Question: How is glass made?

glass

There are also several legends that interpret, with varying degrees of likelihood, the possible prerequisites for how the technology developed.


Question: How is glass made?

glass

N. N. Kachalov reproduces one of them, told by the ancient naturalist and historian Pliny the Elder (I century).


Question: How is glass made?

glass

This mythological version says that one day Phoenician merchants on a sandy shore, for lack of stones, laid a hearth of African soda transported by them - in the morning they found a glass fire on the site of the fire ingot [14].


Question: How is glass made?

glass

Those who study the history of the origin of this material will someday agree on the place — Egypt, Phoenicia or Ancient Mesopotamia, Africa or the Eastern Mediterranean, and so on — and relative to time — “about 6 thousand years ago”, but the feature characteristic of the phenomenology of natural science - “synchronicity of discoveries”, can be observed by some signs and in this case, and does not have The difference is of great importance even in hundreds of years, especially when there are significant differences in the reconstructed method of melting glass.


Question: How is glass made?

glass

The relevance of the legends that tell about the origin of glassmaking is reduced not so much to historical and ethnogeographical aspects, which from the point of view of the theory of knowledge are only indirectly important, but to the origin of the technology as such, as if separated from the “random” processes of pottery, and became the starting point for creating a material with new properties — the first step towards managing them, and in the future — to comprehend the structure.


Question: How is glass made?

glass

There are several versions, one of which makes an attempt to solve the question: what is glass?


Question: How is glass made?

glass

— N. N. Kachalov offers [14]:


Question: How is glass made?

glass

... measure this period from the appearance of glazed ceramics or any glazed silicate products at all.


Question: How is glass made?

glass

Any glaze attached to a clay or silicate shard in general is glass in composition, and the most plausible version of the opening of glass as an independent material is associated with human observation of ceramic technology processes.


Question: How is glass made?

glass

However, the glaze on ancient faience plays a secondary role in the product and is an opaque material, that is, it is devoid of the main distinguishing feature of glass, and therefore can only be called it conditionally.


Question: How is glass made?

glass

A little earlier, the idea of the “glassy relationship” of all silicate materials was expressed by I. F. Ponomarev, and the scientist emphasizes the importance of understanding not so much the genesis of glass as the role of studying its structure to study the properties of other silicate materials; at the same time, he points out that these considerations are still in place for M. IN. Lomonosov Moscow State University [16]:


Question: How is glass made?

glass

The theory of glass structure is important not only for understanding the properties of pure glass products, but also for all silicate products that were at temperatures above +800 °C during the production process.


Question: How is glass made?

glass

It can be assumed that all silicate materials considered by silicate technology contain glass.


Question: How is glass made?

glass

The words of M. IN. Lomonosov, written in the Letter on the Benefits of Glass (1752): “It has porcelain from glass.”


Question: How is glass made?

glass

Not only porcelain, but also faience, ceramics, refractories, cement — all of them contain one or another amount of glass.


Question: How is glass made?

glass

Therefore, the importance of studying glass is extremely expanding and the conclusions drawn in studies on the structure of glass are important for understanding the properties of a wide variety of technical silicate products.


Question: How is glass made?

glass

In studying the technology of Egyptian glassmaking, some success has been achieved by the English researcher A. Lucas.


Question: How is glass made?

glass

His information gives the following idea of the development of glass production in Egypt in the “archaic” period, which ends in the 4th millennium BC. e.


Question: How is glass made?

glass

The so-called “Egyptian faience” (beads, amulets, pendants, small plates for inlays) are products covered with greenish-blue glaze.


Question: How is glass made?

glass

Their attribution to what “faience” is currently associated with cannot be considered correct, since there is no main feature of this category of products - a clay shard.


Question: How is glass made?

glass

Egyptian faience is known with a “shard” of three genera: steatite, soft quartz flour and whole natural quartz.


Question: How is glass made?

glass

It is believed that the earliest samples are made of steatite.


Question: How is glass made?

glass

This mineral is magnesium silicate in composition, it is present in nature in large quantities.


Question: How is glass made?

glass

Products cut from a piece of steatite were covered with a powdered mixture of raw materials that make up its composition to obtain glaze and burned.


Question: How is glass made?

glass

This glaze, which in chemical composition is sodium silicate with a small admixture of calcium, is nothing more than a low-melting glass painted in blue and greenish-blue tones with copper, sometimes with a fair amount of iron [14] [17] [18].


Question: How is glass made?

glass

Egyptian glassmakers melted glass in open hearths in clay bowls.


Question: How is glass made?

glass

The burnt pieces were thrown hot into the water, where they cracked, and these debris, the so-called frits [20], were rubbed into dust by millstones and melted again.


Question: How is glass made?

glass

Fritting was used long after the Middle Ages, so in old engravings and archaeological excavations, we always find two furnaces — one for pre-melting and the other for melting frits.


Question: How is glass made?

glass

The required melting point is +1450 °C, and the operating temperature is from +1100 to +1200 °C.


Question: How is glass made?

glass

The medieval melting furnace (“gut” in Czech) was a low, wood-heated vault, where glass melted in clay pots.


Question: How is glass made?

glass

Lined only from stones and alumina, it could not stand it for a long time, but for a long time there was not enough firewood.


Question: How is glass made?

glass

Therefore, when the forest around the ghuta was cut down, it was transferred to a new place, where forests were still abundant.


Question: How is glass made?

glass

Another furnace, usually connected to the smelting furnace, was an annealing furnace — for tempering, where the finished product was heated almost to the softening point of the glass, and then quickly cooled, thereby compensate for stresses in the glass (prevent crystallization).


Question: How is glass made?

glass

In the form of such a design, the glass-melting furnace lasted until the end of the 17th century, but the lack of firewood forced some ghutas, especially in England, to switch to coal as early as the 17th century; and Sulfur dioxide evaporating from coal turned the glass yellow, and the British began to melt the glass in closed, so-called covered pots.


Question: How is glass made?

glass

This made the melting process more difficult and slowed down, so it was necessary to prepare the charge not so hard, and nevertheless, at the end of the 18th century, the furnace became predominant with coal.


Question: How is glass made?

glass

Interesting information is related to the history of glass and the fact that glass, in a general sense, during its existence, unlike many other materials, has not undergone almost any changes (the earliest samples of what came to be called glass are no different from the well-known bottle glass; the exception, of course, are the types of glasses with desired properties), but in this the case is a substance and material of mineral origin that has found application in modern practice.


Question: How is glass made?

glass

The science of glass


Question: How is glass made?

glass

Mikhail Vasilyevich Lomonosov laid the basis for the scientific approach to the study and cooking of glasses.


Question: How is glass made?

glass

Scientists carried out the first technologically systematized brewing of more than 4 thousand glasses.


Question: How is glass made?

glass

Laboratory practice and methodological principles that he applied are not much different from those currently considered traditional, classical.


Question: How is glass made?

glass

The use of technological properties of mineral glasses


Question: How is glass made?

glass

Natural glass, being one of the first natural materials that was very widely used in everyday life, both as a tool of labor and as part of various types of weapons (knives, arrowheads, spears, etc. hereinafter), — for the manufacture of jewelry and other household items — and as various elements of rituals, for example.


Question: How is glass made?

glass

— Aztec and Mayan; — due to its structure, it also has paradoxical, seemingly paradoxical properties that were used by the same Aztecs who made unique instruments.


Question: How is glass made?

glass

It is the properties of glass as an amorphous substance, on the one hand, which gives it fragility, what is its disadvantage and inapplicability for the manufacture, for example, of tools to which it is presented requirements of increased strength (a former drawback — now it has been overcome in some cases, and a number of technological methods have been overcome), on the other hand, this absence of a crystal lattice has given it an advantage, which is the reason that no metal scalpel can still be compared with the first medical and surgical instruments in history in terms of their sharpness and sharpening capabilities.


Question: How is glass made?

glass

The working part of the latter (chamfer) can be sharpened to a certain limit - in the future it is almost impossible to get rid of the “saw”, while this threshold, for example, is not in obsidian scalpels — the absence of a crystal lattice allows them to be sharpened to the molecular level, which gives an undeniable advantage in microsurgery, and they are not susceptible to corrosion.


Question: How is glass made?

glass

This example, although related to glassy minerals, is very indicative for understanding such a structural property of glass as amorphous.


Question: How is glass made?

glass

But now these properties are also used to create precision tools made of artificial glass [21] [22].


Question: How is glass made?

glass

Glass structure


Question: How is glass made?

glass

The term “glass structure” implies a description of two closely related, but often independently considered aspects — the geometry of the mutual arrangement of the atoms and ions that make up the glass and the character chemical bonds between the particles that form it.


Question: How is glass made?

glass

As already noted, the structure of the glass corresponds to the structure of the liquid in the glass transition interval.


Question: How is glass made?

glass

This determines that the issues of the structure of glass-forming melts and glasses are closely related to each other.


Question: How is glass made?

glass

Any achievement in the study of the structure of liquids and melts creates additional opportunities for the development of the doctrine of the structure of glass and vice versa [2].


Question: How is glass made?

glass

The development of the idea of the structure of glass goes through hypotheses that explain experiments — to theories that are formed mathematically and involve quantitative verification in the experiment.


Question: How is glass made?

glass

Thus, the understanding of the structure of glassy substances (and partially liquid) is due to the perfection of research methods and mathematical apparatus, and technical capabilities.


Question: How is glass made?

glass

The conclusions make it possible to further develop the theory of the structure of glass and similar amorphous substances by improving the methodology [23].


Question: How is glass made?

glass

Research methods


Question: How is glass made?

glass

Strictly speaking, experimental methods for studying the structure of glass date back less than a hundred years, since only the technique can be attributed to such in the entirety of the idea of the structure of glass X-ray analysis, which really gives a real picture of the structure of the substance.


Question: How is glass made?

glass

Among the first who began to use X-ray scattering to analyze the structure of glasses were students of Academician A. A. Lebedev, who back in 1921 put forward the so-called “crystal” hypothesis of the structure of glass, and in the early 1930s, for the purpose of research by this method, was the first in the USSR to organize laboratory group — headed by E.


Question: How is glass made?

glass

A. Porai-Kosice and N. N. Valenkov.


Question: How is glass made?

glass

However, the primary role is not only in the theoretical aspect of the issue, the assessment of thermodynamic characteristics, but also in the implementation of the experiment, in understanding the methodology for its formulation, in assessing and coordinating with the theory of its results is played by so-called model methods.


Question: How is glass made?

glass

These include the EMF method, the electrode method, the mass spectrometric method and the nuclear magnetic resonance method.


Question: How is glass made?

glass

And if the former was already used at the initial stages of the development of electrochemistry, the second owes its origin to the glass electrode, which found full use simultaneously and as an object research (glass electrode material), and as a device that provides information not only about the course of processes in the substance from which it consists, but also indirectly about its structure.


Question: How is glass made?

glass

The electrode method was proposed in the early 1950s by M. M. Schultz.


Question: How is glass made?

glass

Among the first who began to study glass by NMR was the American physicist F. Bray [2].


Question: How is glass made?

glass

Now the arsenal of model methods has been supplemented by the use of confocal optical microscopy, which makes it possible to observe the location of micrometer colloidal particles in volume.


Question: How is glass made?

glass

The atoms forming glass are simulated in the experiment by particles of a colloidal gel suspended in a polymer matrix.


Question: How is glass made?

glass

On experiments led by P. The grand piano is described in the next section [24].


Question: How is glass made?

glass

Classical hypotheses


Question: How is glass made?

glass

The study of the structure of monocrystalline substances even at present requires the improvement of experimental methods and the theory of scattering.


Question: How is glass made?

glass

The theory of M. Laue, the Bragg-Wolfe law and X-ray diffraction analysis of ideal crystals transformed the laws of crystallography by E.


Question: How is glass made?

glass

S. Fedorov into laws based on an understanding of the structure and exact coordinates of atoms of the basis of a single crystal: kinematic for an ideal imperfect (mosaic) crystal, and dynamic for single crystal — provide values of the integral scattering capacity, which in these cases do not correspond to the experimental values for real, much more complex crystals.


Question: How is glass made?

glass

And for materials science, the most important are precisely these deviations from the ideal structure, studied through additional X-ray scattering, which is not implied by either kinematic or dynamic theories of scattering of ideal crystals [23].


Question: How is glass made?

glass

Additional difficulties arise when studying the structures of liquid and glassy substances that do not imply the use of even the similarity of methods of crystallography, crystal chemistry and solid state physics — sciences studying crystalline solids.


Question: How is glass made?

glass

The above prerequisites became the basis for the emergence of almost a dozen hypotheses of the structure of glass, a significant part of them, based only on a relatively narrow range of properties and patterns, subjected to epistemological analysis of the degree of reliability, is devoid of the primary basis for the formation of the theory, however, it is regularly declared with spectacular names.


Question: How is glass made?

glass

There were already crystallites, disorderly mesh, polymer structure, polymer-crystalline structure, ion model, paracrystals, structons, vitroids, glassons, microheterogeneity, submicroheterogeneity, submicroheterogeneity, chemically heterogeneous structure, micellar structure, and other names, the emergence of which is dictated by the need to interpret the results of one, at best, several private experiments.


Question: How is glass made?

glass

Optimists demand a strict general theory of the glassy state, and pessimists generally exclude the possibility of its creation [23].


Question: How is glass made?

glass

Unlike crystalline solids (all atoms are packed in a crystal lattice), in the glassy state there is no such distant order of arrangement of atoms.


Question: How is glass made?

glass

Glass cannot be called an ultra-viscous liquid, which has only a short-range order — the mutual ordering of only neighboring molecules and atoms.


Question: How is glass made?

glass

Glasses are characterized by the presence of the so-called average order of atoms — at distances only slightly higher than interatomic ones [24].


Question: How is glass made?

glass

It is precisely the solution of the issue of the average order, about the possible structural ordering of this kind, that the experiments conducted under the leadership of P. Royal, which should confirm the hypothesis of C. Frank half a century ago, according to which the locking of atoms in the glass structure occurs in the process of mutual penetration of icosahedral groups - 20-sided stereometric figures with five-fold symmetry.


Question: How is glass made?

glass

Preliminary results of experiments with a very simplified glass model suggest the validity of this hypothesis [24].


Question: How is glass made?

glass

Thermodynamic characteristics of glass-forming melts and glasses


Question: How is glass made?

glass

The formation of a primary link (“center”) of crystallization in the melt leads to the appearance of an interface between the crystalline and liquid phases, which leads to an increase in the free energy of the system, which at temperatures below the liquidus temperature, that is, corresponding to a liquid state, thermodynamically less stable than crystalline, otherwise metastable, energy less than the free energy of a liquid of the same masses.


Question: How is glass made?

glass

As the size of the body decreases, the ratio of its surface to volume increases - the smaller radius of the crystallization center corresponds to the increase in free energy associated with the appearance of phase separation.


Question: How is glass made?

glass

For any liquid in a metastable state, at each given temperature, a critical radius of the crystallization center is characteristic, less than which is the free energy of a certain volume of a substance, including this center is higher than the free energy of the volume of matter of the same mass, but without the center.


Question: How is glass made?

glass

At a radius equal to the critical radius, these energies are equal, and at a radius exceeding the critical radius, further growth is thermodynamically natural.


Question: How is glass made?

glass

The contradictions of thermodynamics, fair for macro objects, are removed by the presence of the following phenomenon: constant fluctuations in energy in microobjects (relatively small in number of atoms) affect them internal energy fluctuations of a certain average value.


Question: How is glass made?

glass

With a decrease in temperature, the number of “subcritical” centers increases, which is accompanied by an increase in their average radius.


Question: How is glass made?

glass

In addition to thermodynamic, the kinetic factor affects the rate of formation of centers: the freedom of movement of particles relative to each other determines the rate of formation and growth of crystals [2].


Question: How is glass made?

glass

Glass properties


Question: How is glass made?

glass

Glass is an inorganic isotropic substance, a material known and used since ancient times.


Question: How is glass made?

glass

It also exists in its natural form, in the form of minerals (obsidian — volcanic glass), but in practice — most often as a product of glassmaking — one of the oldest technologies in material culture.


Question: How is glass made?

glass

Structurally — amorphous substance, aggregately classified as solid/liquid.


Question: How is glass made?

glass

In practice, there are a huge number of modifications that imply a lot of various utilitarian capabilities, determined by composition, structure, chemical and physical properties.


Question: How is glass made?

glass

Regardless of their chemical composition and temperature range of solidification, glass has the physical and mechanical properties of a solid body and an ultra-viscous liquid (flows under normal conditions), while maintaining the ability of a reversible transition from a liquid state to a glassy state (this definition allows us to observe that figuratively, glasses, in an expansion sense, include all substances by analogy of the process formation and a number of formal properties, the so-called glassy state - this is where it is exhausted, since the material, as you know, is primarily characterized by its practical qualities, which determine a stricter determination of glass as such in materials science).


Question: How is glass made?

glass

However, the viscosity of glass at room temperature is so high that it has no practical significance — the fluidity of the glass does not appear in any noticeable way for periods of time of tens and hundreds of years [25].


Question: How is glass made?

glass

Currently, materials have been developed for an extremely wide, truly universal range of applications, which is also served by the inherent ones (for example, transparency [26], reflectivity, resistance to aggressive environments, beauty and many others) and previously not characteristic of glass — its synthesized qualities (for example, heat resistance, strength, bioactivity, controlled electrical conductivity and etc.).


Question: How is glass made?

glass

Various types of glass are used in all spheres of human activity: from construction, fine arts, optics, medicine — to measuring equipment, high technologies and astronautics, aviation and military equipment.


Question: How is glass made?

glass

It is studied by physical chemistry and other related and independent disciplines [27].


Question: How is glass made?

glass

In the solid state, silicate glasses are very resistant to conventional reagents (with the exception of hydrofluoric acid, melts or hot concentrated solutions of alkalis and melts of some metals), and the effect of atmospheric factors.


Question: How is glass made?

glass

Their widest application is based on this property: for the manufacture of household items, window panes, glass for transport, glass blocks and many other building materials, medical items, laboratory, research and development, and many other areas.


Question: How is glass made?

glass

For special purposes, chemically resistant glass is produced, as well as glass that is resistant to various types of aggressive influences.


Question: How is glass made?

glass

Physical properties of glass


Question: How is glass made?

glass

The density of glass depends on its chemical composition.


Question: How is glass made?

glass

It is believed that pure quartz glass (fused quartz) has the minimum density among silicate glasses — 2200 kg/m³ (although some borosilicate glasses are less dense).


Question: How is glass made?

glass

On the contrary, the density of glasses (crystal, lead glass, etc.) containing oxides of heavy elements — lead, bismuth, tantalum, barium — reaches 7,500 kg/m³.


Question: How is glass made?

glass

The density of conventional sodium-calcium-silicate glasses, including window glasses, ranges from 2500-2600 kg/m³.


Question: How is glass made?

glass

When the temperature rises from room temperature to 1300° C, the density of most glasses decreases by 6-12%, that is, on average, for every 100° C, the density decreases by 15 kg/m³.


Question: How is glass made?

glass

Young's modulus (modulus of elasticity) of glasses also depends on their chemical composition and can vary from 48·10³ to 12·10³ MPa.


Question: How is glass made?

glass

For example, quartz glass has a modulus of elasticity of 71.4·10³ MPa.


Question: How is glass made?

glass

To increase elasticity, silicon oxide is partially replaced by oxides of calcium, aluminum, magnesium, boron.


Question: How is glass made?

glass

On the contrary, metal oxides reduce the modulus of elasticity, since the strength of MeO bonds is significantly lower than the SiO bond strength.


Question: How is glass made?

glass

Shear modulus 20,000—30,000 MPa, Poisson's ratio 0.25.


Question: How is glass made?

glass

Strength: For ordinary glasses, the compressive strength is from 500 to 2000 MPa (for window glass about 1000 MPa).


Question: How is glass made?

glass

The tensile strength of glass is much lower, which is why the ultimate strength of glass in bending is measured by the ultimate tensile strength.


Question: How is glass made?

glass

This strength ranges from 35 to 100 MPa.


Question: How is glass made?

glass

By tempering glass, it is possible to increase its strength by 3-4 times.


Question: How is glass made?

glass

Another way to increase strength is ion exchange diffusion.


Question: How is glass made?

glass

It also significantly increases the strength of glasses by treating their surface with chemical reagents in order to remove surface defects (tiny cracks, scratches, etc.).


Question: How is glass made?

glass

The hardness of glass, like many other properties, depends on impurities.


Question: How is glass made?

glass

On the Mohs scale, it is 6-7 units, which is between the hardness of apatite and quartz.


Question: How is glass made?

glass

The hardest are quartz glass and low-alkali borosilicate glass.


Question: How is glass made?

glass

As the content of alkaline oxides increases, the hardness of the glass decreases.


Question: How is glass made?

glass

The softest is lead glass.


Question: How is glass made?

glass

Fragility.


Question: How is glass made?

glass

In the region of relatively low temperatures (below the melting point), the glass breaks down from mechanical stress without noticeable plastic deformation and, thus, belongs to perfectly brittle materials (along with diamond and quartz).


Question: How is glass made?

glass

This property can be reflected by the specific impact strength.


Question: How is glass made?

glass

As in previous cases, a change in the chemical composition makes it possible to regulate this property: for example, the introduction of bromine increases the impact strength by almost half.


Question: How is glass made?

glass

For silicate glasses, the impact strength is from 1.5 to 2 kN/m, which is 100 times lower than iron.


Question: How is glass made?

glass

The thermal conductivity of glass is very insignificant and is 0.0017-0.032 cal/ (cm·s·deg) or from 0.711 to 1.339 W/ (m·K).


Question: How is glass made?

glass

For window panes, this number is 0.0023 (0.96).


Question: How is glass made?

glass

Melting point.


Question: How is glass made?

glass

Glass is a thermoplastic material, when heated, it gradually softens and turns into a liquid.


Question: How is glass made?

glass

Melting takes place in a certain temperature range, the value of which depends on the chemical composition of the glass.


Question: How is glass made?

glass

Below the glass transition temperature Tc, the glass becomes brittle.


Question: How is glass made?

glass

For ordinary silicate glass, Tc = 425-600°C.


Question: How is glass made?

glass

Above the melting point, the glass becomes a liquid.


Question: How is glass made?

glass

At these temperatures, the glass mass is processed into products.


Question: How is glass made?

glass

Glassy state


Question: How is glass made?

glass

Glasses are formed as a result of supercooling of melts at a rate sufficient to prevent crystallization.


Question: How is glass made?

glass

Due to this, the glasses usually retain an amorphous state for a long time.


Question: How is glass made?

glass

Inorganic melts capable of forming a glass phase pass into a glassy state at temperatures below the glass transition temperature Tg (at temperatures above Tg, amorphous substances behave as melts, that is, they are in a molten state).


Question: How is glass made?

glass

Glass can be obtained by cooling melts without crystallization.


Question: How is glass made?

glass

Almost any substance from the molten state can be converted to a glassy state.


Question: How is glass made?

glass

Some melts (such as individual glass-forming substances) do not require rapid cooling for this.


Question: How is glass made?

glass

However, some substances (such as metal-containing melts) require very rapid cooling to avoid crystallization.


Question: How is glass made?

glass

Thus, to obtain metal glasses, cooling rates of 105-106 K/s are required.


Question: How is glass made?

glass

Glass can also be obtained by amorphizing crystalline substances, for example, by bombarding with an ion beam, or by depositing vapors on cooled substrates.


Question: How is glass made?

glass

While the value of the property of a liquid (both stable and metastable) is due only to its composition, temperature and pressure, the value of the property of a non-equilibrium liquid or glassy substance depends also from the structural condition.


Question: How is glass made?

glass

In this case, it is tempting to describe the structure of an arbitrary liquid as a single parameter.


Question: How is glass made?

glass

As a result, the proposed by A. Tulom [28] is a method for describing the structural state of a glassy substance by characterizing the so-called structural temperature Tf (fictive temperature), that is, one at which the test glass with a given structure is in an equilibrium state [2].


Question: How is glass made?

glass

Subsequently, it was revealed that it was practically impossible to describe the glassy state by one value of the structural temperature and the need to use a whole range of such temperatures [29].


Question: How is glass made?

glass

Currently, along with the relaxation interpretation, the glass transition of amorphous substances is explained by the formation during cooling of a sufficient number of interatomic bonds, which gives the substance solid-state properties, and not only a change in the Hausdorff dimension of the bond system from fractal to three-dimensional was revealed [30], but also the formation of fractal structures during glass transition [31].


Question: How is glass made?

glass

The viscosity of amorphous substances is a continuous function of temperature: the higher the temperature, the lower the viscosity of the amorphous substance.


Question: How is glass made?

glass

Usually, melts of glass-forming substances have a high viscosity compared to melts of non-glass-forming substances [32].


Question: How is glass made?

glass

Glasses, in particular, due to their polymer structure, have the ability to heterogeneity.


Question: How is glass made?

glass

The polymerization of glasses in the glassy state gives them individual qualities, which, depending on the nature of these structural formations, determine the degree of transparency and other properties of the glasses.


Question: How is glass made?

glass

The presence of compounds of a chemical element, metal oxide, in the glass composition can affect its color, degree of electrical conductivity, and other physical and chemical properties.


Question: How is glass made?

glass

Glass composition and technology


Question: How is glass made?

glass

Glass-forming substances


Question: How is glass made?

glass

Glass-forming substances include:


Question: How is glass made?

glass

Oxides:


Question: How is glass made?

glass


Question: How is glass made?

glass


Question: How is glass made?

glass


Question: How is glass made?

glass


Question: How is glass made?

glass


Question: How is glass made?

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Fluorides:


Question: How is glass made?

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Question: How is glass made?

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and others.


Question: How is glass made?

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The main groups of glass by chemical composition


Question: How is glass made?

glass

Depending on the main glass-forming substance used, glasses can be oxide (silicate, quartz, germanate, phosphate, borate), fluoride, sulfide, and so on.


Question: How is glass made?

glass

Types of silicate glass


Question: How is glass made?

glass

The basic method for producing silicate glass is to melt a mixture of quartz sand (SiO2), soda (Na2CO3) and calcium carbonate (CaCO3).


Question: How is glass made?

glass

The result is a compound of Na2O·CaO·6SiO2 composition.


Question: How is glass made?

glass

As the main component, glass contains 70—75% of silicon dioxide (SiO2), obtained from quartz sand, provided that it is properly granulated and free from any contaminants.


Question: How is glass made?

glass

The Venetians used pure sand from the Po River or even imported it from Istria, while Bohemian glassmakers obtained sand from pure quartz.


Question: How is glass made?

glass

The second component, calcium oxide (CaO), makes the glass chemically resistant and enhances its shine.


Question: How is glass made?

glass

It goes to the glass in the form of lime.


Question: How is glass made?

glass

Ancient Egyptians obtained calcium oxide from crushed stone of sea shells, and in the Middle Ages it was prepared from tree ash or seaweed, as limestone as a raw material for making glass was not yet known.


Question: How is glass made?

glass

Bohemian glassmakers were the first to mix chalk with the glass mass in the 17th century.


Question: How is glass made?

glass

The next component of glass is alkali metal oxides — sodium (Na2O) or potassium (K2O), which are necessary for melting and making glass.


Question: How is glass made?

glass

Their share is about 16—17%.


Question: How is glass made?

glass

They go to glass in the form of soda (Na2CO3) or potash (K2CO3), which decompose into oxides at high temperatures.


Question: How is glass made?

glass

Soda was first obtained by leaching seaweed ash, and in an area remote from the sea, potash containing potassium was used, obtained by leaching ash from beech or conifers.


Question: How is glass made?

glass

There are three main types of glass:


Question: How is glass made?

glass

Soda-lime glass (1Na2O:1CaO:6SiO2)


Question: How is glass made?

glass

Potassium-lime glass (1K2O:1CaO:6SiO2)


Question: How is glass made?

glass

Potassium-lead glass (1K2O:1PbO:6SiO2)


Question: How is glass made?

glass

Soda-calcium glass


Question: How is glass made?

glass

“Soda glass” (“cronglass”, “crown”) can be easily melted, it is soft and therefore easy to process, and in addition, it is clean and light.


Question: How is glass made?

glass

Potassium-calcium glass


Question: How is glass made?

glass

“Potash glass”, unlike sodium glass, is more refractory, hard and not so plastic and capable of forming, but has a strong gloss.


Question: How is glass made?

glass

Because it used to be obtained directly from ash, which contains a lot of iron, the glass was greenish in color, and in the 16th century manganese peroxide was used to bleach it.


Question: How is glass made?

glass

And since it was the forest that provided the raw materials for the manufacture of this glass, it was also called forest glass.


Question: How is glass made?

glass

There was a ton of wood per kilogram of potash.


Question: How is glass made?

glass

Lead glass


Question: How is glass made?

glass

Lead glass (crystal, “flintglass”, “flint”) is obtained by replacing calcium oxide with lead oxide.


Question: How is glass made?

glass

It is quite soft and fusible, but very heavy, has a strong shine and a high refractive index, decomposing light rays into all colors of the rainbow and causing a play of light.


Question: How is glass made?

glass

Borosilicate glass


Question: How is glass made?

glass

The inclusion of boron oxide instead of the alkaline components of the charge gives this glass the properties of refractoriness, resistance to sudden temperature jumps and aggressive media.


Question: How is glass made?

glass

The change in composition and a number of technological features, in turn, affect the cost price — it is more expensive than conventional silicate.


Question: How is glass made?

glass

It is used for the manufacture of laboratory glassware.


Question: How is glass made?

glass

Quartz glass


Question: How is glass made?

glass

Pure quartz glass is obtained by melting high-purity siliceous raw materials (usually quartzite, rock crystal), its chemical formula is SiO2.


Question: How is glass made?

glass

The features of quartz glass are transparency for ultraviolet rays, refractoriness and a coefficient of thermal expansion close to zero.


Question: How is glass made?

glass

For the latter reason, it is resistant to temperature changes and uneven heating.


Question: How is glass made?

glass

One of the main modern areas of use is halogen lamp cylinders operating at high temperatures and bulbs of ultraviolet gas-discharge lamps.


Question: How is glass made?

glass

It is also sometimes used as a material for precision mechanical parts, the dimensions of which should not change when the temperature changes.


Question: How is glass made?

glass

An example is the use of quartz glass in precision pendulum clocks.


Question: How is glass made?

glass

Quartz glass can also be of natural origin (see clastofulgurites above), formed when lightning hits quartz sand deposits (this fact underlies one of the historical versions the origin of the technology).


Question: How is glass made?

glass

The composition of some industrial glasses


Question: How is glass made?

glass

Clarified glass


Question: How is glass made?

glass

Improving the processes of removing and neutralizing coloring impurities in the manufacture of architectural and interior sheet glasses allowed manufacturers to announce the production of “clarified” glass of various trade marks, characterized by improved color reproduction of objects behind the glass and greater light transmission.


Question: How is glass made?

glass

In the translated descriptions of branded glasses, the term “enlightened” is found, but these glasses do not have any optical enlightenment, being simply discolored in the mass.


Question: How is glass made?

glass

Dyes, silencers


Question: How is glass made?

glass

In the production of glass, dyes are of great importance, which not only affect the color of the finished product, but also change and accelerate the course of physico-chemical reactions during the melting of glass melt.


Question: How is glass made?

glass

Silencers are additives that increase the dispersion of light in the glass, from light opality to complete milky opacity.


Question: How is glass made?

glass

Since ancient times, glasses have been stained by adding metal compounds to the melt, most often oxides.


Question: How is glass made?

glass

For example, in modern production, CrO3, blue — CuO, green — FeO, Fe2O3, olive brown — V2O3, V2O5, purple and lilac — NiO and Mn2O3 are used to produce yellow glass.


Question: How is glass made?

glass

The color of the glass depends not only on the type of oxide, but also on its amount.


Question: How is glass made?

glass

For example, cobalt (II) oxide produces blue glass in small quantities, and violet-blue in large quantities.


Question: How is glass made?

glass

Copper (II) oxide in sodium-calcium glass gives a blue color, and green in potassium-zinc glass.


Question: How is glass made?

glass

Internal stresses in glass products


Question: How is glass made?

glass

When the product or workpiece from glass cools, uneven cooling, complex shape, heterogeneity of the melt lead to the formation of internal mechanical stresses in the mass of the material.


Question: How is glass made?

glass

If the workpiece that cools too quickly does not burst by itself - further machining, accidental mild impact, temperature drop can destroy such glass, even if the impact seems insignificant.


Question: How is glass made?

glass

Due to the redistribution of stresses in the amorphous mass of glass, the product may crack over time and for no apparent reason at all.


Question: How is glass made?

glass

To relieve internal stresses, long-term annealing of glass is used at a temperature at which the change in the shape of the product can still be neglected, but the glass is already gaining sufficient fluidity.


Question: How is glass made?

glass

Massive cast products cool down very slowly, for example, mirror blanks of unique telescopes — for several months.


Question: How is glass made?

glass

The presence of stresses in the glass can be checked using a polariscope: the stressed areas of the glass rotate the polarization plane of the transmitted light in different ways, and the device clearly demonstrates the internal condition of the material.


Question: How is glass made?

glass

At the same time, glass in some cases lends itself to hardening, which creates a controlled compressive stress in the surface layers.


Question: How is glass made?

glass

Improving the mechanical properties of glass


Question: How is glass made?

glass

The theoretical strength (breaking) of ideal glass, according to various estimates, is 20-30 times greater than the strength of structural steels [33].


Question: How is glass made?

glass

The main drawback of real glasses — fragility — is due to the presence of surface and internal microdefects, which become the centers from which the destruction of the glass part begins.


Question: How is glass made?

glass

Strength can be increased either by smoothing out these defects, or by forcing the glass surface to work only in compression under any real loads on the part.


Question: How is glass made?

glass

Smoothing of surface defects is achieved by polishing — mechanical, chemical or fire (surface melting).


Question: How is glass made?

glass

For example, chemical polishing by etching in hydrofluoric acid can increase the strength of glass from tens to hundreds to 5000MPa.


Question: How is glass made?

glass

The latter value is close to the natural limit, due to the realistically achievable homogeneity of the internal structure.


Question: How is glass made?

glass

However, finely polished glass must be immediately and reliably protected from new microdamages caused as a result of normal handling (touching in a dusty atmosphere, etc.).


Question: How is glass made?

glass

Without this, the strength of the glass quickly decreases to a level close to its original level.


Question: How is glass made?

glass

The essence of the second method consists in creating a pre-compressive stress in the surface layers of the glass, which compensates for the tension of the inner layers in the working part.


Question: How is glass made?

glass

This is achieved by quenching, applying glass enamel coatings, changing the chemical structure of the surface.


Question: How is glass made?

glass

Tempering, that is, rapid cooling, of an amorphous material, such as glass, leads to the fact that the hardened and cooled surface layers continue to contract by the cooling and hardening inner layers, as it were, the difference in linear dimensions between the outer cold and inner hot layers and the resulting deformations and stresses are “frozen”.


Question: How is glass made?

glass

Hot enameling creates on the surface a layer of glass of equivalent strength with a pre-selected lower temperature coefficient of linear expansion, and even with a relatively slow cooling the part to normal operating temperature, this layer is compressed.


Question: How is glass made?

glass

Chemical modification of the surface is either the removal of alkaline ions from the silica structure in a hot state, which reduces the TCLE of the surface (approaching quartz glass), or the exchange of sodium ions to larger ones (potassium, etc.) at a low temperature, causing the surface layer to “swell” (for example, the well-known Gorilla Glass for smartphone displays).


Question: How is glass made?

glass

Tempered glass on impact (car accident, broken door or architectural panel) collapses into small obtuse fragments that resemble cereals and do not cause serious injuries.


Question: How is glass made?

glass

Hence the English term “safety glass” (“safety glass”).


Question: How is glass made?

glass

In Russia, for such glass, the name “stalinite” is found, due to the time of its introduction into the widespread practice of automotive and military production.


Question: How is glass made?

glass

The method of strengthening and protecting finished glass structures (windows of houses and cars, screens of phones and tablets) is to stick on them various polymer films with a thickness of about 0.1-2.0 mm.


Question: How is glass made?

glass

The protective films are hard enough to withstand scratches, and are elastic and knit enough not to crack when the glass breaks.


Question: How is glass made?

glass

The strength of thick “armor” films for windows and showcases, when properly attached to the frame, allows you to withstand the knocking out of the window with a metal tool for some time [34].


Question: How is glass made?

glass

Even films have been created that make the glass bulletproof [35].


Question: How is glass made?

glass

Reinforcement (building glass of the “frost” type), contrary to popular belief, weakens the glass and makes it more fragile compared to the same monolithic glass.


Question: How is glass made?

glass

Reinforcing wire in architectural panels serves to hold large fragments of untempered glass and, along the way, for decorative purposes.


Question: How is glass made?

glass

Cutting, machining


Question: How is glass made?

glass

Cutting glass is splitting it according to the applied risk, which serves as a stress concentrator and determines the direction of the split.


Question: How is glass made?

glass

The voltage can be created both by traditional bending and by local heating by a flame or an electric spiral.


Question: How is glass made?

glass

The cutting line does not have to be straight - spot heating allows you to crack along fairly steep curves.


Question: How is glass made?

glass

The risk applied should be deep enough, but at the same time have even clean edges without chipping; it is recommended to pre-lubricate the glass with oil or kerosene.


Question: How is glass made?

glass

The risk should be fresh — due to the natural amorphous fluidity of the glass, the applied feature “swims”, and in a few minutes it will be more difficult to break the glass.


Question: How is glass made?

glass

Diamond used to be used as a cutter, but now it is almost exclusively hard alloys.


Question: How is glass made?

glass

Carbide cutters allow drilling and even turning glass, but the main method of machining is various types of grinding, from simple edge forming interior glass and engraving on tableware to the manufacture of laboratory thin sections and precision shaped parts.


Question: How is glass made?

glass

Of the specific abrasives, it is possible to note the previously used “crocus” (iron (III) oxide) and the “polyrite” (cerium dioxide) that replaced it for the processing of automobile windows, as well as the well-known “GOI paste” (State Optical Institute) based on chromium dioxide.


Question: How is glass made?

glass

Mask etching in hydrofluoric acid is used to apply inscriptions, diffraction gratings and similar microrelief to glass.


Question: How is glass made?

glass

Glass-to-metal adhesion


Question: How is glass made?

glass

For vacuum production, laboratory equipment, electronics, the ability of glasses to form a stable gas-tight junction with certain metals and alloys is important.


Question: How is glass made?

glass

At the dawn of vacuum technology, platinum wire was used for the manufacture of soldered inputs into glass, the temperature coefficient of expansion of which is equal to that for common silicate glasses.


Question: How is glass made?

glass

For mass production, such a junction, of course, was not suitable.


Question: How is glass made?

glass

As the needs of the electric lamp industry increased, work was carried out in three directions: the development of special glasses with TCR equal to the TCR of the metal used, the creation of an input material from the TCR, corresponding to common glass, and improving the technology of soldering materials with different TCR.


Question: How is glass made?

glass

In the first case, the result was the creation of “molybdenum”, “tungsten”, “titanium”, etc. glasses, the name of which has nothing to do with the chemical composition, but indicates consistency in TCR with appropriate metal; for example, the “leg” of an incandescent lamp with soldered molybdenum filament holders.


Question: How is glass made?

glass

In the second, “platinite” was created, a bimetallic wire made of nickel steel coated with copper in the amount of a quarter of the total mass of the wire; the TCR of these metals, summed up in such a proportion, correspond to the TCR of borosilicate glass, and copper covered with an oxide film easily forms a gas-tight seam of a characteristic brick color, which can be seen in all fluorescent and radio tubes.


Question: How is glass made?

glass

In the third case, unlike the first two, an “inconsistent” junction is formed (for example, borosilicate glass with a copper part), which is stable mainly due to the elasticity of the thin-walled metal parts and within a narrow temperature range.


Question: How is glass made?

glass

The use of various types of glass


Question: How is glass made?

glass

Optical glass


Question: How is glass made?

glass

Special technical requirements are imposed on optical glass.


Question: How is glass made?

glass

Among them is homogeneity, estimated on the basis of expert analysis by the degree and number of swirls in it and transparency in a given spectrum range.


Question: How is glass made?

glass

Specific formulations (for example, the addition of rare earth elements) make it possible to finely select the optical properties of glasses to create complex optical systems with the best compensation for distortions.


Question: How is glass made?

glass

Depending on the values of the refractive index and the dispersion index (or average dispersion), optical glasses are divided into different types.


Question: How is glass made?

glass

GOST 3514-94 establishes the following types of colorless optical glasses [37]:


Question: How is glass made?

glass

Light crowns (LC)


Question: How is glass made?

glass

Phosphate crowns (FC)


Question: How is glass made?

glass

Heavy phosphate crowns (TPA)


Question: How is glass made?

glass

Crowns (K)


Question: How is glass made?

glass

Barite crowns (BC)


Question: How is glass made?

glass

Heavy crowns (TK)


Question: How is glass made?

glass

Superheavy crowns (STK)


Question: How is glass made?

glass

Special crowns (OK)


Question: How is glass made?

glass

Cronflint (CF)


Question: How is glass made?

glass

Barite flints (BF)


Question: How is glass made?

glass

Heavy barite flints (TBP)


Question: How is glass made?

glass

Light flints (LF)


Question: How is glass made?

glass

Flints (F)


Question: How is glass made?

glass

Heavy Flints (TF)


Question: How is glass made?

glass

Superheavy Flints (STF)


Question: How is glass made?

glass

Special Flints (FF)


Question: How is glass made?

glass

Each type includes several brands of glass, in total, their number, determined by GOST, is 180.


Question: How is glass made?

glass

The processing of optical glass is no less important than the properties of the material, and moreover, it is closely related to the mechanical and temperature characteristics of the glass.


Question: How is glass made?

glass

Only taking into account the whole complex of factors (heating during grinding, distribution of forces and deformations during installation of the workpiece, etc.) makes it possible to obtain an optical element with a shape strictly corresponding to the design one.


Question: How is glass made?

glass

High-grade optical glasses are used in the most science-intensive areas of industry — military, aerospace, when creating devices for basic scientific research and consumer top class optics.


Question: How is glass made?

glass

Therefore, the achieved level of technology for manufacturing and processing optical glass reflects the level of development of industry as a whole.


Question: How is glass made?

glass

Clear and colored glass


Question: How is glass made?

glass

Clear glass


Question: How is glass made?

glass

The production of antique glass was based on the use of untreated natural materials — sand, ash, soda, poor contaminated minerals.


Question: How is glass made?

glass

As a result, the glass was often cloudy and full of inclusions.


Question: How is glass made?

glass

The recipe for transparent glass was known in ancient times, as evidenced by ancient bottles and balsamaria, including colored ones — on Pompeian frescoes we see completely transparent dishes with fruit.


Question: How is glass made?

glass

But until the Middle Ages, when stained glass windows are becoming widespread, it is not necessary to find samples of glassmaking that clearly have these properties [38] [39].


Question: How is glass made?

glass

Glass is actively used in construction, in particular, in translucent structures of buildings.


Question: How is glass made?

glass

Colored glass


Question: How is glass made?

glass

The usual glass mass after cooling has a yellowish-green or bluish-green tint.


Question: How is glass made?

glass

Glass can be colored if, for example, oxides of certain metals are added to the charge, which will change its structure during cooking, which, after cooling, in turn, causes the glasses extract specific colors from the spectrum of light passing through them.


Question: How is glass made?

glass

Glandular compounds color glass in colors - from bluish-green and yellow to red-brown, manganese oxide - from yellow and brown to purple, chromium oxide - herbaceous green, uranium oxide - in yellowish-green (uranium glass), cobalt oxide blue (cobalt glass), nickel oxide purple to gray-brown, antimony oxide or sodium sulfide yellow (the most beautiful yellow however, stains colloidal silver), copper oxide - red (the so-called copper ruby, unlike the gold ruby, obtained by increasing colloidal gold).


Question: How is glass made?

glass

Bone glass is obtained by clouding the glass mass with burnt bone, and milk glass by adding a mixture of feldspar and fluorspar.


Question: How is glass made?

glass

By the same increments, having clouded the glass mass to a very weak extent, opal glass is obtained.


Question: How is glass made?

glass

Painted glasses, among other applications, are used as color filters.


Question: How is glass made?

glass

The development of stained glass art is associated with the production of transparent colored glasses of a given shape.


Question: How is glass made?

glass

Another known type of colored glass is mosaic smalt, often hand cooked, irregular shapes, various shades and degrees of muffling.


Question: How is glass made?

glass

Classical examples of the use of smalt are the decoration of Byzantine churches and architectural ensembles of Samarkand.


Question: How is glass made?

glass

Art glass


Question: How is glass made?

glass

This material initially, both due to the variety of its decorative capabilities, and due to its unique properties, including the likeness of the most beautiful gems, and sometimes surpassing them in some ways, it is through visual creativity, from the moment when the ingot was first in the palm of the master, pleases and, probably, will always, enchanting, be present in the life of those who are able to appreciate its beauty.


Question: How is glass made?

glass

It would be superfluous to recall that once only glass could compete with gold at its cost.


Question: How is glass made?

glass

Indeed, his earliest handmade samples are jewelry.


Question: How is glass made?

glass

Glass blowing is an operation that allows you to obtain various shapes from a viscous melt — balls, vases, glasses.


Question: How is glass made?

glass

From the point of view of glassblower, glasses are divided into “short” (refractory and heat-resistant, for example, “pyrex”), plastic in a very narrow temperature range, and “long” (low-melting, for example, lead) — which have a much wider range.


Question: How is glass made?

glass

The most important working tool of the glassblower, its blow tube, is a hollow metal tube 1—1.5 m long, one-third covered with wood and equipped with a brass mouthpiece at the end.


Question: How is glass made?

glass

Using a tube, the glass blower collects molten glass from the furnace, blows it in the form of a ball and forms it.


Question: How is glass made?

glass

To do this, he needs metal scissors to cut off the glass mass and attach it to the tube, long tweezers made of metal for pulling and forming the glass mass, to form embossed ornaments, etc., a cut for cutting off the entire product from the tube and a wooden spoon (rolling pin, bobbin shape) for leveling the collected glass melt.


Question: How is glass made?

glass

The glass blower inserts the pre-molded glass (“jar”) with these tools into a mold made of wood or iron.


Question: How is glass made?

glass

The remaining trace (nozzles, cap) must be removed by grinding.


Question: How is glass made?

glass

The finished product is knocked off from the tube to the forks and carried into the annealing furnace.


Question: How is glass made?

glass

The product is annealed for several hours at a temperature of about 500 °C in order to relieve the stresses that have arisen in it.


Question: How is glass made?

glass

An unannealed product can crumble because of them at the slightest touch, and sometimes spontaneously.


Question: How is glass made?

glass

For demonstration purposes, this phenomenon has long been effectively shown in Batavian tears — frozen drops of glass.


Question: How is glass made?

glass

Glass grinding and polishing


Question: How is glass made?

glass

Glass cut


Question: How is glass made?

glass

Glass metallization and coloring


Question: How is glass made?

glass

Modern low-budget types of art work with glass — fusing and lampwork, creating small ornaments and decorative items using a hand burner or a small tabletop electric stove.


Question: How is glass made?

glass

They do not require a special workshop, complex stationary equipment and a lot of energy, sophisticated techniques that come with many years of experience, and materials for a start can be simply beads and bottles.


Question: How is glass made?

glass

Glass enamel


Question: How is glass made?

glass

Enamel based on a thin glass powder fixed by reflow is widely used as a resistant finish coat for ceramic tiles, ceramic and metal dishes, metal and faience sanitary ware, galvanic baths and chemical appliances, surfaces of cookers, tanks of washing machines and water heaters, medical and food equipment.


Question: How is glass made?

glass

Artistic “hot enamel” is a material with a relatively rich palette, excellent durability and brilliance, widely used in pottery and tile art.


Question: How is glass made?

glass

The term “enamel”, currently applied to polymer-based opaque paints, is etymologically related to the term “smalt”, from the German smalt, “melt”.


Question: How is glass made?

glass

Enameling ceramic products gives them the hygienic properties characteristic of glass, makes them smooth, shiny and hardens the surface (the appearance of the faience cup before enameling can be present by a rough rim at its bottom or side used for installation in a dryer and kiln).


Question: How is glass made?

glass

Before the spread of durable polymer decals used today to decorate cheap earthenware, the colorful pattern on ceramics was applied exclusively by hot enameling.


Question: How is glass made?

glass

Enameling of steel and cast iron baths, chemical, medical, culinary vessels and appliances gives them chemical resistance, hardness and durability of glass surfaces combined with strength metal.


Question: How is glass made?

glass

Enameling was especially common before the mass use of stainless steels and plastics in these areas.


Question: How is glass made?

glass

The enamel is applied to the surface in the form of a mixture of glass powder with water (slip) with a density from a liquid suspension to a non-flowing mass, or by spraying a dry powder.


Question: How is glass made?

glass

After drying in air or with a little heating, the product is heated to the melting point of the enamel glass (firing at 600-900° C) and slowly cooled.


Question: How is glass made?

glass

The glass is fused into an impermeable film, adheres to the surface and is partially absorbed into it if it is porous or rough.


Question: How is glass made?

glass

If the glass and the base are chosen correctly, and the enamel layer is thin enough, the product resists temperature jumps well.


Question: How is glass made?

glass

For greater strength, several layers are applied with firing each - for example, on the edges of metal dishes, baths, you can see a black or bluish layer of primer enamel with the addition of cobalt and nickel for better adhesion to metal.


Question: How is glass made?

glass

Unfortunately, glass enamel is fragile, and when the metal base is mechanically shaken, bent or warped, it forms chips and cracks that expose the metal.


Question: How is glass made?

glass

Repair of enamel coating is complicated and far from always expedient.


Question: How is glass made?

glass

Polymeric materials for local repair are short-lived and unstable in comparison with glass, peel off along the border of heterogeneous coatings, the patch loses its original color, turns yellow from time to time or absorbs dyes.


Question: How is glass made?

glass

For the renovation of worn domestic baths and industrial containers, a continuous coating with a thick layer of polymer material (the well-known service of “enameling baths”) or a plastic liner is often used that follows their shape.


Question: How is glass made?

glass

However, such repairs rarely give the resistance that hot enameling provided under the same conditions.


Question: How is glass made?

glass

Artistic enamel painting on ceramics or more refractory glass is technologically quite simple and widespread even in amateur conditions (a method of firing enamel products in household microwave oven [40]).


Question: How is glass made?

glass

To obtain different colors, either colored glasses are ground, or pigments are added to the finished powder or slip.


Question: How is glass made?

glass

In addition to hand painting, both author's and “conveyor”, there is a simple stencil decoration and machine full-color printing — also with the subsequent firing of the applied powder.


Question: How is glass made?

glass

It is necessary to distinguish traditional hot enamel from modern polymer paints and decals - materials that reduce the cost of technology, do not require high temperatures to fix, but also do not have resistance and the characteristic picturesque features of glass.


Question: How is glass made?

glass

Glass enamel compositions are also used for electrical insulation of surfaces (for example, in capacitors) and as a high-temperature “glue” when assembling (metal) ceramic housings of electronic and other devices.


Question: How is glass made?

glass

Photochromic, thermochromic and athermal glasses


Question: How is glass made?

glass

Photo and thermochromic glasses can reversibly change light absorption under the influence of light or temperature, respectively.


Question: How is glass made?

glass

Photochromic glasses that darken in the light have been widely used since the middle of the 20th century as lenses for chameleon glasses, for glazing buildings in hot climates.


Question: How is glass made?

glass

On cars, such glass did not take root due to inappropriate darkening characteristics, but thermal glasses are often used that poorly transmit infrared rays and reduce the heating of the interior by the sun; they can be distinguished by their characteristic, as a rule, greenish hue.


Question: How is glass made?

glass

Electrochromic glass


Question: How is glass made?

glass

For applications with controlled changes in transparency, electrochromic materials have been created — multilayer glasses and tint films, which are a package of transparent electrodes and a polymer film -matrices with inclusions of liquid crystals or inorganic ions, enclosed between layers of ordinary glass or protective films for sticking on an existing glass element.


Question: How is glass made?

glass

When voltage is applied to the electrodes, the relative position of inclusions in the matrix changes, changing the optical properties of the package.


Question: How is glass made?

glass

The glass itself in the package acts only as a power and protective structural element, in contrast to photochromic glasses that are colored in the mass.


Question: How is glass made?

glass

Smart glass


Question: How is glass made?

glass

Smart glass is a modern collective term for glass, window and interior glass structures whose characteristics and functions go beyond the traditional limits.


Question: How is glass made?

glass

These can be glasses that change their optical properties (dullness, transmittance, heat absorption coefficient, etc.) when the illumination, temperature changes or when electrical voltages, interior panels with room heating function, sound emitting or switching to matte projection screen mode.


Question: How is glass made?

glass

The broadest interpretation of the concept of “smart” glazing in architecture may even include, for example, windows with mechanical automatic ventilation systems.


Question: How is glass made?

glass

Car smart glass, as a rule, means electrochromic triplex.


Question: How is glass made?

glass

Glass as a dielectric


Question: How is glass made?

glass

As a material for insulators, glass is distinguished by high electrical strength, resistance to surface breakdown, relatively low dielectric losses, heat resistance, gas tightness of the material and junctions, inertia, relative strength and high dimensional stability, invariability of parameters over time with the appropriate choice of modes.


Question: How is glass made?

glass

Glass insulators are used in high-voltage power lines, in the vast majority of vacuum devices, housings of capacitors, transistors, microcircuits, indicators, relays and others electronic components, especially those of critical designs.


Question: How is glass made?

glass

Capacitors are known in the form of a sintered package of metal plates insulated with glass, and wires in heat-resistant fiberglass insulation.


Question: How is glass made?

glass

Glass lasers


Question: How is glass made?

glass

Special types of glass (doped with neodymium, non-silicate, etc.) is widely used as an active medium for solid-state lasers.


Question: How is glass made?

glass

Glass makes it possible to create active elements of large size and good optical quality, for a variety of applications from commercial metalworking to experiments on thermonuclear synthesis with a pulse power of hundreds of terawatts.


Question: How is glass made?

glass

pH metry


Question: How is glass made?

glass

At the beginning of the 20th century, when studying the behavior of glass in electrolyte solutions, a close to linear dependence of the EMF of a galvanic cell was discovered, one of the electrodes of which is made of ordinary sodium glass (in practice, in the form of a thin, weakly conductive glass film covering a fairly electrically conductive body), from the concentration of hydrogen ions in the solution (pH).


Question: How is glass made?

glass

It became possible to directly measure how “acidic” or “alkaline” the test solution is using a sensitive voltmeter.


Question: How is glass made?

glass

Working with a glass electrode is easier and cheaper than with a platinum electrode, advantages over chemical indicators are continuity of measurement, strict quantitative assessment, no effect on the solution, the ability to include the meter in the automatic control circuit of chemical equipment.


Question: How is glass made?

glass

The glass electrode is chemically inert and stable in time.


Question: How is glass made?

glass

The theory of the glass electrode was developed in detail in the middle of the 20th century as a result of purposeful efforts of science related to the creation of industrial technologies for the production of weapons-grade uranium and plutonium.


Question: How is glass made?

glass

Now pH meters are generally available, and the scope of application of ionometry (measuring not only pH, but also the concentration of other ions using appropriate electrodes) is extremely wide.


Question: How is glass made?

glass

Porous glass


Question: How is glass made?

glass

When treating ordinary silicate glass with water or acid solutions, compounds of alkali metals and boron are washed out of its surface, leaving a sponge film of bonded silicon dioxide molecules.


Question: How is glass made?

glass

By selecting the composition and heat treatment of the original glass, solvent and leaching conditions, it is possible to achieve almost complete leaching of Na2O and boric anhydride, obtaining a rigid silica structure with through pores of molecular size, preserving the appearance of the glass sample taken.


Question: How is glass made?

glass

Such a material is characterized by good repeatability of pore size, its small spread in the sample and can be used as an effective selective adsorbent in chromatography, gas separation and other substances, biosynthesis, as a substrate for fixing microorganisms, a molecular filter, a catalyst carrier and in many other fields of science, technology and medicine.


Question: How is glass made?

glass

Foam glass


Question: How is glass made?

glass

Foam glass should not be confused with porous glasses - a heat-insulating building and structural material obtained by foaming glass due to additives to the charge that emit gases at high temperature.


Question: How is glass made?

glass

Foam glass is characterized by the presence of relatively large closed pores, low specific gravity (floats in water), opacity.


Question: How is glass made?

glass

It is used in the form of molded building blocks and shaped parts of thermal insulation, granules like expanded clay, crushed gravel chips for filling cavities and filling lightweight concrete.


Question: How is glass made?

glass

When applied to construction, it has good heat and fire resistance, sufficient chemical and biological inertness, does not absorb water, does not emit fine and fibrous dust.


Question: How is glass made?

glass

Glass fibre and fiberglass


Question: How is glass made?

glass

From ordinary glass, it is possible to obtain thin, very flexible threads suitable for making fabric.


Question: How is glass made?

glass

A monofilament of any required length is made by a melt extract, spraying a glass jet with hot gas - a cotton-like mass of short fibers.


Question: How is glass made?

glass

Glass fibers are very strong and tough (tensile strength is comparable to steel, elasticity to hard aluminum alloys), are cheap to produce, retain dielectric properties, chemical resistance and refractoriness of glass.


Question: How is glass made?

glass

Fabrics, linear threads and staple (cotton-wool) glass fiber are used to produce a huge number of composite fibers (fiberglass, fiberglass, glass-filled injection plastics), electrically insulating (woven glass tape, wire braids) and heat-insulating (glass wool, non-woven fabric) materials.


Question: How is glass made?

glass

Fiberglass reinforcement for concrete is gaining popularity in construction, as well as volume-distributed reinforcement of concrete mixes with alkali-resistant glass fibers (roving) and rolled bitumen roofing on fiberglass fabrics.


Question: How is glass made?

glass

At the same time, glass wool and other non-bound fiberglass materials, when used inaccurately, release fine dust from sharp hard fibers that can damage the skin and respiratory organs.