简介：Inabreakthroughthatcouldrevolutionizehumanity'srelationshipwithillnessanddisease,amethodofvaccinationhasbeendevelopedthatprovidesinstantimmunity,USresearchersannouncedMonday.

简介：instantcoffee(速溶咖啡)的问世,已使instant一词成为现代生活和科学技术中不可缺少的一个词。instant原义为“立即的,紧急的”,现在它已经有了许多引申意义。一、instant充当形容词时可以表示:1.已制好的、快速方便的、速溶的、使用方便的

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简介：Bismuth(Bi)-dopedphotonicmaterials,whichexhibitbroadbandnear-infrared(NIR)luminescence(1000–1600nm),areevolvingintointerestinggainmedia.However,thetraditionalmethodshaveshowntheirlimitationsinenhancingBiNIRemission,especiallyinthemicroregion.Consequently,thetypicalNIRemissionhasseldombeenachievedinBi-dopedwaveguides,whichhighlyrestrictstheapplicationofBi-activatedmaterials.Here,superbroadbandBiNIRemissionisinducedinsituinstantlyinthegratingregionbyafemtosecond(fs)laserinsideborosilicateglasses.Aseriesofstructuralandspectroscopiccharacterizationsaresummonedtoprobethegenerationmechanism.AndweshowhowthisnovelNIRemissioninthegratingregioncanbeenhancedsignificantlyanderasedreversibly.Furthermore,wesuccessfullydemonstrateBi-activatedopticalwaveguides.TheseresultspresentnewinsightsintoBi-dopedmaterialsandpushthedevelopmentofbroadbandwaveguideamplification.

简介：ViathevaluableopportunityoftheThreeGorgesReservoir(TGR)135-mfillinginJune2003,theYangtzedischargeandsuspendedsedimentconcentration(SSC)enteringtheestuaryduringtheperiodfrom15Mayto15July2003wereanalyzedtoexaminetheinstanteffectsofthefillingonthem.TheYangtzedischargeandSSCenteringtheestuaryintheperiodsbefore,duringandafterthefillingclearlyindicatedthreephases:1)thepre-storagephasecharacterizedbynaturalconditions,inwhichtheSSCincreasedwithincreasingwaterdischarge;2)thestoragephase,duringwhichtheSSCdecreaseddramaticallywithdecreasingwaterdischarge;and3)thepost-storagephase,duringwhichboththeSSCandwaterdischargeremainedatrelativelylowlevelsfirstuntiltheendofJune,thentheSSCincreasedgraduallywithincreasingwaterdischarge.ItseemsthatthetimesfortheinstanteffectsofthedecreasingdischargedownstreamfromtheupperYangtzeontheYangtzedischargeandSSCenteringtheestuaryduetotheTGR135-mfillingtotakeplacewereabout5dand1drespectively,whilebothwereabout18dforthoseoftheincreasingdischarge.Thisprobablyreflectsthebufferingandresultantlyhysteresisofthe1800-kmstretchfromtheupperYangtzetotheestuary.TheresultsarehelpfulforscientificandhydrologicalinvestigationoftheYangtzemainstreamdownstreamfromtheTGRDamandoftheestuarineandadjacentcoastalwaters.

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