简介：Accordingtotheconsiderationoftheadvantageofdrilling,itisusuallyakindofprac-ticethathelpsstudentstoacquirefluencyinthelanguagebytrainingthemtoproducelan-guagepatternsautomaticallyandwithoutconsciouseffort.Butinrecentyears,thereisagreatandheatedarguementaboutdrillingactivities.
简介：Magnetohydrodynamicsisoneofthemajordisciplinesinsolarphysics.Vigorousmagnetohydrodynamicprocessistakingplaceinthesolarconvectionzoneandatmosphere.Itcontrolsthegeneratingandstructuringofthesolarmagneticfields,causestheaccumulationofmagneticnon-potentialenergyinthesolaratmosphereandtriggerstheexplosivemagneticenergyrelease,manifestedasviolentsolarflaresandcoronalmassejections.Nowadaysdetailedobservationsinsolarastrophysicsfromspaceandonthegroundurgeagreatneedforthestudiesofmagnetohydrodynamicsandplasmaphysicstoachievebetterunderstandingofthemechanismormechanismsofsolaractivity.Ontheotherhand,thespectacularsolaractivityalwaysservesasagreatlaboratoryofmagnetohydrodynamics.Inthisarticle,wereviewedafewkeyunresolvedproblemsinsolaractivitystudiesanddiscussedtherelevantissuesinsolarmagnetohydrodynamics.
简介：Tetradecyldimethylbenzylammoniumsalt(TDMBA)cationswereintercalatedintosodiummontmorillonite(Na-MMT)byanionexchangereaction.TheresultingTDMBA-MMTwascharacterizedbyFourier-transforminfraredspectroscopy(FTIR),thermogravimetricanalysis(TGA),andX-raydiffraction(XRD).Moreover,theantibacterialactivityandwater-resistanceofTDMBA-MMTwereinvestigated.TheresultsshowthatTDMBAcationsareintercalatedintotheNa-MMT.TheonsettemperatureofdecompositionofTDMBAcationsinTDMBA-MMTisraisedabout60℃higherthanthatoftetradecyldimethylbenzylammoniumchloride(TDMBACl),andthed_((001))spacingenlargedfrom1.23nmto2.10nm.0.1mg/mLTDMBA-MMTisfullyenoughtokillalltheStaphylococciaureus(S.aureus)andmorethan99.99%oftheEscherichiacoli(E.coli)inasamplesolutionwithin6.0htouch,andtheTDMBA-MMTalsoshowslongactingproperties.
简介：Chronicdiseaseshavebecomeafocalpointofpublichealthworldwidewithestimatesoftrillionsofdollarsinannualhealthcarecostandcausingmorethan36milliondeathsayear.Lifestylefactorssuchasphysicalinactivityareheavilycorrelatedwiththedevelopmentofmanychronicdiseases.Newstrategiesforprimaryandsecondarydiseasepreventionaredesperatelyneededtoaidinbluntingthenegativeeconomicandsocialimpactofthesediseases.Physicalactivity(PA)andexercisearenowconsideredprincipalinterventionsforuseinprimaryandsecondarypreventionofchronicdiseases.Currently,moreemphasisinprimarypreventionofdiseaseisnecessarytoreducediseaseriskinyouthandadults;howeverwithchronicdiseaseprevalencesohigh,similaremphasisisalsonecessaryforsecondarypreventioninthosechildrenandadultsalreadyinflictedwithchronicdiseases.Conditionssuchascardiovasculardisease,type2diabetes,obesity,andcanceraredrasticallyimprovedwhenPAandexercisearepartofamedicalmanagementplan.Inaddition,thenationalPAguidelinesinconjunctionwithPApromotiontoolslikeExerciseisMedicine?areneededtopromoteincreasedPAandexerciselevelsworldwide.
简介：ThispaperaimstopresentanexperimentdevelopedinatechnologydegreecollegeinS?oPaulo:thefreshmenintegrationandremedialclassesweek.Thisworkwasdevelopedduetothedropoutratethatoccurredinseveralcourses.The50%dropoutratewascollectedthroughasampleofthefirstsemesterfrom2012to2014.Thiscollegehascoursesinweldingtechnology,mechanicalmanufacturing,industrialautomationandrefrigeration,airconditioning,andventilationandheating.Itisapubliccollege.Astheyarecoursesoftheareaofmechanicalengineering,theirfirstsemestersconsistofcalculus,physics,chemistry,statistics,andotherdisciplinesthatrequiresolidknowledgebackgroundfromseniorhighschool.Thisisnottherealityfortheprofileofincomingstudents.Ninety-fivepercentofthestudentscomefrompublicschools.Remedialclassesweekiscomprisedofremedialclassesonmathematics,motivationallectures,presentationoftheacademic,andjobmarketarea,aswellasintegrationwithveteranstudents,teachers,andcoordinators.Thisworkbeganin2014andtherewas35%evasionreduction.
简介：Thesixmultiimidazolecopper(Ⅰ)complexesareutilizedtomimictyrosinase.Themainproductis3,5-di-t-butylcatecholfromo-hydroxylationofthesubstrate2,4-di-t-butylphenol.Thehighestyieldofcatecholisupto82.2%andselectivity94.8%by[Cu(I)_(3b)(MeCN)_2](ClO_4)_2andO_2undermildconditions,whicharefoundtobemoreefficientthanthatalreadyreported.
简介：Anewmethacrylamidemonomer,hexylaminemethacrylamide(MAHA),wassynthesizedandusedinpolymerizations.ThehomopolymerofMAHAanditscopolymersweresynthesizedbyfreeradicalpolymerizationtechniqueswithN-isopropylacrylamide(NIPAAm)intwodifferentcompositions.Thequaternizationofthehomopolymerandcopolymerswerecarriedoutusing1-bromopropane.ThecopolymerswithNIPAAmandalowMAHAcontentshowedtemperature-responsivebehaviorinanaqueousenvironment.Thelowercriticalsolutiontemperatures(LCSTs)ofthesepolymersvariedbetween32℃and44℃.TheLCSTsofquaternizedcopolymerswerehigherthanthoseofneutralcopolymersbecausetheyweremorehydrophilic.TheobtainedhomopolymersandcopolymersweretestedforantibacterialactivitiesagainstS.aureusandE.coli.Thequaternizedwater-solublecopolymersshowedantibacterialactivitiesagainstS.aureus.Thequaternizationresultedinthesynthesisofbothantibacterialandtemperature-responsivecopolymers.
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