Clarifications in example notebook
Clarifications in example notebook

liangjg/openmc,amandalund/openmc,samuelshaner/openmc,johnnyliu27/openmc,smharper/openmc,liangjg/openmc,johnnyliu27/openmc,samuelshaner/openmc,shikhar413/openmc,johnnyliu27/openmc,wbinventor/openmc,wbinventor/openmc,smharper/openmc,amandalund/openmc,shikhar413/openmc,shikhar413/openmc,walshjon/openmc,shikhar413/openmc,walshjon/openmc,bhermanmit/openmc,amandalund/openmc,walshjon/openmc,wbinventor/openmc,smharper/openmc,liangjg/openmc,paulromano/openmc,samuelshaner/openmc,mit-crpg/openmc,mit-crpg/openmc,walshjon/openmc,bhermanmit/openmc,smharper/openmc,paulromano/openmc,mit-crpg/openmc,amandalund/openmc,mit-crpg/openmc,paulromano/openmc,samuelshaner/openmc,liangjg/openmc,wbinventor/openmc,paulromano/openmc,johnnyliu27/openmc