Fix memory leak
Fix memory leak

thewtex/tomviz,OpenChemistry/tomviz,cryos/tomviz,OpenChemistry/tomviz,cjh1/tomviz,thewtex/tomviz,OpenChemistry/tomviz,cryos/tomviz,cjh1/tomviz,OpenChemistry/tomviz,thewtex/tomviz,mathturtle/tomviz,cryos/tomviz,cjh1/tomviz,mathturtle/tomviz,mathturtle/tomviz