简介:Fibrestressofglassfibrereinforcedpolymericcopmositesonloadisdeterminedbyusingopticalfibreasmodelfiberandbymeansoflaserinterferencemethod.Inaddition,theoriginationoffibrestressduringmouldingprocessofcompositesandtherelationbetweenfiberstressofloadedcompositesandexternalstressareexamined.Theexperimentsshowthatfibrestressisrelatedtomolecularstructureofinterfacialmaterialsandstructureofinterfaciallayers.Whenstressistransferredfrommatrixtofibre,eachinterfaciallayerhasdifferentstressgradientanddeformability.Thispropertycanbecharacterizedbyintroducinganinterfacialstresstransfercoefficientktothetwo-phasemodel.
简介:AnewcompoundK6Ti0.67Nb15.33O42waspreparedforthefirsttimebysolidstatereactioninK2O-Ni2O3-Nb2O5ternarysystem.Thenewcompoundwascharacterizedbyelectronprobe,X-raypowderdiffractionandDTA.TheresultofX-raypowderdiffractionshowsthatK6Ti0.67Nb15.33O42crystallizesthehexagonalsystemwithunitcellparametersa=9.1341(5)A,c=12.090(1)A.andspacegroupP62/mcm(193).