完整word版MP重点归纳特殊标记出来的2.docx
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完整word版MP重点归纳特殊标记出来的2
MP1
1.Pleasedeterminetrueorfalseaboutthefollowingstatements:
a.Inorganicandorganicmaterialsareallbelongtometal-typematerial(F)
b.Allcarbonbasedmaterialsareorganicmaterials.(F)
c.Materialscienceincludesmaterialchemistryandmaterialphysics(T)
d.Insomesense,materialengineeringcanbetreatedasmaterialprocessing.(T)
MP3
Plspickoutthetruestatementsamongthefollowingitems:
a)Newphaseusuallymakesnucleationatdefectpoints.T
b)Solidstatephasetransformationiseasiertoidentify.F
c)Precipitationisasecondordersolidphasetransformation.F
d)PhasediagramreflectsphasesunderthermodynamicequilibriumconditionsT
e)Insolidstatephasetransformation,thenewphasegenerallygrowsalonghabitplane.T
f)Polycrystallinetransformationisafirstorderphasetransformationanditisdiffusional.T
g)Insecondorderphasetransformation,thereexistvolumeandentropychangesF
h)Eutectoidtransformationisakindofdiffusionaltypetransformation.T
MP4
Trueorfalsequestions:
a)Theyieldstrengthshowstheresistanceofthematerialstopermanentdeformation.T
b)Theplasticdeformationisakindoftemporarydeformation.F
c)Theyieldstressofceramicsisgenerallyhigherthanthatofmetals.T
d)Themaximumstrengthinthestress-straincurveistheyieldstrength.F
e)Ductilityindicatesthegeneralabilityofamaterialtobeplasticallydeformed.T
f)Plasticdeformationisgenerallyrealizedbyatomicplaneslipping.T
g)Metalspossesslargedislocationwidth,resultinginsmallyieldstrength,thusmoreductile.Whileceramicspossesssmalldislocationwidth,thuslatticeresistanceislarge,leadingtobrittlefeature.T
h)Materialwithmoreslipsystemexhibitsbetterductility.T
MP5
9.trueorfalsequestions
1)Ifonlythefreecarrierdensityishigh,materialexhibitshighconductivity.F
2)Theconductivityofsemiconductorsislowerthanmetal.T
3)Freeelectronsinmetalpossesswaveparticleduality.T
4)Maxwellboltzmanstatisticsisnotvalidtofreeelectroninmaterials.T
5)Bose-einsteinstatsticsbelongstoquantumstatistics,applyingtosystemthatdoesnotobeyPaullexclusiverule.T
MP6
1.Trueorfalsequestions
1)EnergydistributionoffreeelectronsinametalobeysFermi-Diracdistribution(T)
2)Thenumberofoccupiedcollectiveelectronenergystatesinametalcrystalisequaltothetotalnumberofvalenceelectrons(T)
3)AccordingtothePauliprinciple,eachenergystatecanonlyaccommodatetwoelectronswithoppositespins.(T)
4)ThemostenergeticvalenceelectronsinthemetalatT=0KlocalatFermilevel.(T)
5)TheFermilevelinametalisrelatedtothedensityoffreeelectroninmetal.Anditisusuallytreatedasconstantatdifferenttemperature.(T)
6)Accordingtoquantumfreeelectrontheory,thedistributionoffreeelectronagreeswithMaxiwell-Boltzmannstatistics.(F)
7)Althoughthreearemanyelectronenergylevelsinmetals,electronsgenerallyoccupytheenergylevelsbelowFermilevel,andonlyelectronsnearFermilevelcanbeexcitedtohigherenergylevelsbythermalactivation.(T)
1.ConsideringtwoBrillouinzones,generally,thebandwidthiswiderinthehigherenergyband,plsdothetrueorfalsequestions
a)AwiderbandwidthmeansenergydispersionintheBrillouinzoneislarger,andelectronstheretendstopossesshigherdelocalizationabilityT
b)ThenumberenergystatesindifferentbrillouinzoneisdifferentF
c)ElectronsinaenergybandwithwiderwidthwillbemoremobilethanthosewithnarrowbandwidthT
MP7
1.Trueorfalsequestion:
1)AccordingtoOhmlaw,theelectriccurrentisproportionaltotheelectricfield.T
2)ThefreeelectronsinmetalsobeyPauliexclusiveprinciple.T
3)Themovementofvalenceelectronsinametalonlyinfluencesbylatticevibration,butisnotaffectedbyimpurityanddefect.(F)
4)Theconductivityofmetalsdecreaseswiththeincreaseoftemperature.(T)
5)TheorderofmetalconductivityisAl6)Phononrelatestothevibrationoflattice,itsenergyisquantizedandincreaseswithtemperature.T
MP8
1.Trueorfalseandblankfillinquestions.
a)Theintrinsicsemiconductorsonlyincludesiliconandgermanium.F
b)Mobilitydecreaseswithimpurityconcentration.T
c)Insemiconductor,carrierconcentrationdecreaseswithtemperature.F
d)Insemiconductor,conductivitydecreaseswithtemperature.F
e)withtheincreaseofdopingconcentration,thecarrierconcentrationincreases.T
MP9
(1)Inasuperconductor,belowTc,thefreeenergyislowerinthestateofsuperconductorthaninthenormalstate.T
(2)Inasuperconductor,belowTc,thespecificheatcapacityislowerinthestateofsuperconductorthaninthenormalstate.F
(3)SuperconductingquantuminterferencedeviceutilizesthesuperconductorfeatureofJosephsonEffect.T
(4)ThezeroresistanceofasuperconductorisduetotheformationofCooperpairbytheassistingoflatticephonon.T
(5)Whenasuperconductorinafixedmagneticfield,iscooledtotemperaturebelowTC,itwillexpelthemagneticfield.T
MP10
1)Innonpolardielectricmaterials,thestatisticcentersofthepositiveandnegativechargesofmoleculesoverlap.T
2)Comparedtopolardielectricmaterials,thedielectricconstantofanonpolardielectricmaterialislower.T
3)Thermoelectriceffectisirreversible.F
4)Foraparallelplatecapacitorinvacuum,thecapacitanceishigherintheoneemployingaluminumastheelectrodesthantheonewithsilveraselectrodes.F
5)Inadielectricmaterial,applyingaalternativeelectricfield,thephaseofchargingcurrentwillbethesameasthatoftheelectricfield.F
6)Therefractiveindexrelatestothepolarizationofdielectricmaterialunderopticalfrequencythatonlyresponsestotheelectricpolarization.T
MP11
1)Heatcapacityisindependentofspinarrangement.F
2)Theheatcapacityofonematerialisdependentoncrystalstructure.T
3)Thefactorsthatcontributetoheatcapacityincludeatomicvibrationandelectronvibration.T
4)Comparedtometal,thecapacityofceramicsshowsmoreagreementwithDebyemodelbecausetherearehardlyfreeelectronsthere.T
MP12
Trueorfalsequestions
1)Incopper,thedominantfactorforthermalconductionisphonon.F
2)Formetalswithrelativelylowelectricalconductivityandatrelativelylowtemperature,bothelectronandphononarethemaincontributionforthermalconduction.T
3)ThethermalconductivityofmaterialsisindependentoftemperatureF
4)ThethermalconductionbyphonontakeseffectonlyathightemperatureT
5)Inagoodconductor,theratioofthermalandelectricalconductivitiesisproportionaltoabsolutetemperature.T
6)Generallyspeaking,athermalconductivityofametalalloyislowerthancorrespondingmetal.T
7)Thethermalconductivityofaceramicwithcrystallinestructureisgenerallylowerthanthatinamorphousstate.F
8)Comparedtoopaqueamorphousceramic,thesharperincreasingofthermalconductionathightemperatureinatransparencyamorphousceramicisduetophotonthermalconduction.T
9)Inanisotropicmaterial,thevolumeexpansioncoefficientisthreetimesthelinearexpansioncoefficient.T
10)Generallyspeakingthethermalexpansioncoefficientisreciprocaltomeltingpoint.T
MP13
1)ThespinmagneticmomentofaelectronisapproximatelyequaltoBohrmagneton.T
2)Twomagneticmomentswithoppositedirectionwillcanceleachother.T
3)Inferromagneticmaterials,thereexistsstrongcouplingamongadjacentmagneticmoments.T
4)Adiamagneticmaterialexhibitsnopermanentmagneticmomentsinatoms.T
5)Inaparamagneticmaterial,thereisnopermanentmagneticmomentsinatoms.F
6)Inamagneticatom,therearegenerallyunpairedelectrons.T
7)Amongallmaterials,themagneticsusceptibilityinferromagneticoneisthehighest.T
8)Belowthecriticaltemperature,thesusceptibilityofasuperconductoris-1.T
9)Inantiferromagneticmaterials,thereexiststrongmagneticmomentcouplings.T
10)Generally,thesusceptibilityofaantiferromagneticmaterialissmallerthanthatofaparamagneticone.T
MP14
1.Trueorfalsequestions.
1)Themagneticsusceptibilityofaparamagneticmaterialisdecreaseswithtemperature.T
2)AbovetheCurrietemperature(TC),themagneticsusceptibilityofaferromagneticmaterialislargerthanthosebelowTC.F
3)Aferromagnetwithonlyonedomainpresentmacromagnetismandtherearemagnetostaticenergy.T
4)Iftherearealotofmagneticdomainsinaferromagnetandthesedomainsarerandomlydistributed,magnetismwillpresent.F
5)Adiamagnetisputinexternalmagneticfield(H),themagneticinductionisalmostproportionaltoH.T
MP15
2Trueorfalsequestions:
a)Thedegreeoflightreflectiondependsonitswavelength(T)
b)Thedegreeoflightabsorptiondependsonboththewavelengthoflightandtheelectronicstructureofmaterial.(T)
c)Thedegreeoflightrefractionisindependentoflightwavelengthbutonlydependentonmaterial.(F)
d)Thehigherthematerialrefractiveindex,thehigherthereflectance.(T)
e)Theratiooftheabsorbedlightisindependenttotheintensityoftheincidentlight,butisproportionaltothelengthofthemedium.(T)
f)Generallyspeaking,theabsorbedlightbymetaltendstobereleasedasemissionwithwavelengthdifferenttotheabsorption.(F)
g)Inmetals,thesmallpartoftheabsorbedphotonsthatdosenotinvolveradiativedecayconvertstoheateventually.(T)
h)Anonmetalmaterialcanbeeithertransparentoropaquedependingonitsabsorptionproperty.(T)
i)Therefractiveindexofmaterialsisgenerallygreaterthan1.(T)
j)Thecolorofametalisdeterminedbythewavelengthsofreflect