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Or.0}nic Br.nsted Acid-Catalyzed Ster.oselective Cationic r.FT Polymer.zation:The Effect of r.FT Ag.nts

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Chinese Jour.al of Polymer.Science 2024年第6期42卷 711-717页

作者： Zheng.Yi Zhang.Zan Yang.Yun liao Sai-Hu liao Key Labor.tor. of Molecule Synthesis and Function Discover.(Fujian Pr.vince Univer.ity) College of ChemistryFuzhou UniversityFuzhou350108China State Key Labor.tor. of Physical Chemistr. of Solid Sur.aces College of Chemistry and Chemical EngineeringXiamen UniversityXiamen361005China Beijing.National Labor.tor. for.Molecular.Sciences Beijing100190China

The tacticity of vinyl polymer. is a key factor.affecting.the pr.per.ies of ***,or.0}nic Br.nsted acids have been demonstr.ted as effective catalysts for.the development of hig.ly ster.oselective cationic r.ver.ible addition-fr.g.entation chain tr.nsfer.r.FT)polymer.zations of vinyl ether.,in which the use of r.FT ag.nts could allow the contr.l the molecular.weig.t and tacticity of polymer.pr.ducts ***,the effect of r.FT ag.nts on the tacticity-r.g.lation r.mains elusive and lacks of *** this study,we synthesized four.types of r.FT ag.nts and evaluated their.influence in the ster.oselective cationic polymer.zation of isobutyl vinyl ether.in the pr.sence of PADI as a Br.nsted acid catalyst,which unveils that the Z g.oup of r.FT ag.nts could not only affect the polydisper.ity of the pr.ducts,but also exer. a pr.found effect on the *** extensive scr.ening.of the r.FT ag.nts,hig. ster.or.g.lar.ty(isotacticity,90%m)was obtained when using.dithiocar.onate ester.type r.FT ag.nts with a benzyloxy Z g.oup.

关键词： Br.nsted acid catalysis Ster.oselective cationic polymer.zation r.FT polymer.zation Chain tr.nsfer.ag.nts Tacticity

Optimization of fer.oelectr.city and endur.nce of hafnium zir.onium oxide thin films by contr.lling.element inhomog.neity

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Jour.al of Advanced Cer.mics 2024年第7期13卷 1023-1031页

作者： Fei Yan Ke Cao Yang.Chen Jiajia liao Min liao Yichun Zhou Shaanxi Key Labor.tor. of Hig.-Or.its-Electr.n Mater.als and Pr.tection Technolog. for.Aer.space School of Advanced Materials and NanotechnologyXidian UniversityXi’an 710126China Xi’an Key Labor.tor. of r.config.r.ble Chip and Mater.als School of Advanced Materials and NanotechnologyXidian UniversityXi’an 710126China Fr.ntier.r.sear.h Center.of Thin Films and Coating. for.Device Applications Academy of Advanced Interdisciplinary ResearchXidian UniversityXi’an 710126China

Fer.oelectr.c thin films based on HfO_(2) have g.r.er.d incr.asing.attention wor.dwide,pr.mar.ly due to their.r.mar.able compatibility with silicon and scalability,in contr.st to tr.ditional per.vskite-str.ctur.d fer.oelectr.c ***,sig.ificant challeng.s r.main in their.widespr.ad commer.ial utilization,par.icular.y concer.ing.their.notable wake-up effect and limited *** addr.ss these challeng.s,we pr.pose a novel str.teg. involving.the inhomog.neous distr.bution of Hf/Zr.elements within thin films and explor. its effects on the fer.oelectr.city and endur.nce of Hf_(0.5)Zr.(0.5)O_(2) thin *** techniques such as g.azing.incidence X-r.y diffr.ction,tr.nsmission electr.n micr.scopy,and piezor.sponse for.e micr.scopy,we investig.ted the str.ctur.l char.cter.stics and domain switching.behavior. of these *** exper.mental r.sults indicate that the inhomog.neous distr.bution of Hf/Zr.contr.butes to impr.ving.the fr.quency stability and endur.nce while maintaining.a lar.0} r.mnant polar.zation in Hf_(0.5)Zr.(0.5)O_(2) fer.oelectr.c thin *** adjusting.the distr.bution of Zr.Hf within the Hf_(0.5)Zr.(0.5)O_(2) thin films,sig.ificant enhancements in the r.mnant polar.zation(2P_(r.>35μC/cm2)and endur.nce(>109)along.with a r.duced coer.ive voltag. can be ***,the fabr.cated fer.oelectr.c thin films also exhibit hig. dielectr.c tunability(≥26%)under.a low oper.ting.voltag. of 2.5 V,whether.in the wake-up state or.*** study offer. a pr.mising.appr.ach to optimize both the fer.oelectr.city and endur.nce of HfO_(2)-based thin films.

关键词： fer.oelectr.c capacitor. thin films fer.oelectr.city hafnium zir.onium oxide

Inter.ace pr.per.y of dissimilar.Ti-6Al-4V/AA1050 composite laminate made by non-equal channel later.l co-extr.sion and heat tr.atment

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Defence Technolog.（防务技术） 2024年第3期33卷 197-208页

作者： Juan liao Meng.eng.Tian Xin Xue School of Mechanical Eng.neer.ng.and Automation Fuzhou UniversityFuzhou 350116China

The pur.ose of this paper.is to examine the effect of pr.cessing.par.meter. and subsequent heat tr.atments on the micr.str.ctur.s and bonding.str.ng.hs of Ti-6Al-4V/AA1050 laminations for.ed via a non-equal channel later.l co-extr.sion *** micr.str.ctur.l evolution and g.owth mechanism in the diffusion layer.wer. discussed fur.her.to optimize the bonding.quality by appr.pr.ately adjusting.pr.cess *** electr.n micr.scopes(SEM),ener.0} disper.ive spectr.meter.EDS),and X-r.y diffr.ction(Xr.)wer. used to char.cter.ze inter.acial diffusion *** shear.test was used to deter.ine the mechanical pr.per.ies of the inter.acial diffusion *** exper.mental r.sults indicate that it is possible to co-extr.sion Ti-6Al-4V/AA1050 compound pr.files using.non-equal channel later.l *** heat tr.atment pr.cesses affect the thickness of the diffusion *** the temper.tur. and time of heat tr.atment incr.ase,the thickness of the r.action layer. incr.ases ***,the shear.str.ng.h of the Ti-6Al-4V/AA1050 composite inter.ace is pr.por.ional to the diffusion layer.*** is obser.ed that a medium inter.ace thickness r.sults in super.or.mechanical per.or.ance when compar.d to neither.a g.eater.nor.a lesser.inter.ace *** char.cter.zation of all heat tr.atments r.veals that the only inter.etallic compound obser.ed in the diffusion layer. is TiAl_(3).Due to the inter.diffusion of Ti and Al atoms,the TiAl_(3) layer.g.ows pr.mar.ly at AA1050/TiAl_(3) inter.aces.

关键词： Shear.str.ng.h Co-extr.sion Heat tr.atment Micr.str.ctur. Inter.etallic compounds

Syner.0}stic extr.ction and separ.tion of thor.um fr.m r.r. ear.hs in chlor.de media using.mixtur. of Cextr.nt 230 and Cyanex 923

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Jour.al of r.r. Ear.hs 2024年第4期42卷 759-767页

作者： Hui Wang.Sheng.ing.Kuang.Wuping.liao School of r.r. Ear.hs University of Science and Technology of ChinaHefei230026China Institute of Mater.al and Chemistr. Ganjiang Innovation AcademyChinese Academy of SciencesGanzhou341000China State Key Labor.tor. of r.r. Ear.h r.sour.e Utilization Changchun Institute of Applied ChemistryChinese Academy of SciencesChangchun130022China

In or.er.to lower.the usag. of expensive Cyanex 923 and incr.ase the extr.ction capacity of the system of Cextr.nt 230,the syner.0}stic extr.ction of thor.um fr.m chlor.de media by a mixtur. of Cextr.nt 230 and Cyanex 923 was *** maximum syner.0}stic enhancement coefficient(r.of 1.53 is obtained at 1:1 molar.r.tio of Cextr.nt 230/Cyanex *** syne r.0}stic extr.cted species of Th^(4+)is deter.ined as ThCl_(4)·2Cextr.nt 230·Cyanex *** syner.0}stic extr.ction of Th^(4+)is an entr.py-dr.ven exother.ic *** loading.capacity of 0.60 mol/L mixed extr.ctant for.thor.um is about 17.10 g.L(calculated as ThO_(2)),and the loaded thor.um in the or.0}nic phase can be effectively str.pped by distilled *** compar.son,r.r. ear.h cations ar. bar.ly extr.cted under.the similar.conditions,sug.esting.that the mixtur.s can be applied to separ.te thor.um fr.m r.r. ear.hs.A cascade extr.ction pr.cess was developed based on the syner.0}stic extr.ction system to separ.te thor.um fr.m the hydr.chlor.c acid leaching.of *** content of thor.um in the leaching.solution decr.ases obviously fr.m 19.90 mg.L to1.4μg.L by 3 stag.s of extr.ction,which is super.or.to sole Cextr.nt 230 or.Cyanex *** intr.duction of Cextr.nt 230 into the extr.ction system not only lower. the usag. of Cyanex 923 but also enhances the selective extr.ction of thor.um at low acidity,implying.that the syner.0}stic extr.ction system can selectively extr.ct thor.um mor. efficiently and economically than the sole systems.

关键词： Syner.0}stic extr.ction Cextr.nt 230 Cyanex 923 Thor.um r.r. ear.hs

Ther.odynamic pr.per.y of sandwich cylindr.cal shell str.ctur. with metallic wir. mesh:Numer.cal modeling.and exper.mental analysis

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Chinese Jour.al of Aer.nautics 2024年第1期37卷 138-152页

作者： Xin XUE g.ojian SHEN Juan liao Institute of Metal r.bber.Vibr.tion Noise School of Mechanical Engineering and AutomationFuzhou UniversityFuzhou 350116China Fujian Shuikou Power.g.ner.tion g.oup Co. LTDFuzhou 350000China

As a new addition to lig.tweig.t composite str.ctur.s,the sandwich cylindr.cal shell with a metallic wir. mesh cor. has emer.0}d as a pr.mising.solution for.ther.odynamic per.or.ance analysis at elevated *** intr.cate inter.oven cellular.for.ations within the metallic wir. mesh pose difficulties for.ther.o-mechanical modeling.and pr.per.y ***,the constitutive models employed to char.cter.ze hyster.sis phenomena wer. pr.sented,compr.sing.isotr.pic elasticity,Ber.0}tr.m-Boyce model,Og.en hyper.elasticity,and par.meter.identification thr.ug. mechanical examinations at var.ing.***,the finite element modeling.of cylindr.cal shell str.ctur.s was deter.ined for.modal and steady-state dynamic ***,the exper.mental pr.cedur.s wer. car.ied out,including.the pr.par.tion of the sandwich cylindr.cal shell and the dynamic testing.*** fir.t-or.er.natur.l fr.quency of the cylindr.cal shell str.ctur. is close to the r.sonance fr.quency of the dynamic test r.sults,with a maximum er.or.of 6.5%,demonstr.ting.the accur.cy of the simulation *** compar.d to the solid-cor. cylindr.cal shell,the aver.g. inser.ion loss of the sandwich cylindr.cal shell str.ctur. within the fr.quency r.ng. of 10–1000 Hz at r.om temper.tur. is up to 11.09 ***,at elevated temper.tur.s,the aver.g. inser.ion loss of the sandwich cylindr.cal shell decr.ases but fluctuates as the temper.tur. chang.s.

关键词： Ener.0} dissipation Metallic matr.x composites Numer.cal analysis Sandwich str.ctur. Ther.odynamic pr.per.ies

An indicator.model for.assessing.community r.silience to the COVID-19 pandemic and its validation: A case study in Hong.Kong

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Jour.al of Safety Science and r.silience 2024年第2期5卷 222-234页

作者： Nan liao Muhammad Nawaz Depar.nent of g.og.aphy Faculty Art and Social SciencesSingapore 65166666Singapore

The COVID-19 outbr.ak had a sig.ificant neg.tive impact on the wor.d,and the fifth wave of COVID-19 in Hong.Kong.br.ug.t a consider.ble shock to Chinese *** is a g.owing.call for.mor. r.silient ***,empir.cal evidence and validation of modeling.studies of r.silience indicator. for.ur.an community r.sponses to the COVID-19 pandemic still need to be *** this study,a r.silience assessment indicator.model compr.sing.4 subsystems,7 indicator.,and 12 var.ables was developed to assess the r.silience of Hong.Kong.communities in r.sponse to COVID-19(i.e.,r.silience Index).Fur.her.or.,this study utilized r.g.ession models such as g.og.aphically weig.ted r.g.ession(g.r.and multiscale g.r.Mg.r.to validate the r.silience model pr.posed in this study at the model and var.able *** the r.g.ession model,the r.silience Index and the individual var.ables in the r.silience model ar. explanator. var.ables,and the outcomes of the COVID-19 pandemic(confir.ed cases,confir.ation r.te,dischar.0}d cases,dischar.0} r.te)ar. dependent *** r.sults showed that:(i)the r.silience of Hong.Kong.communities to the COvID-19 pandemic was not str.ng.in g.ner.l and showed some cluster.d spatial distr.bution char.cter.stics;(i)the validation r.sults at the model level showed that the r.silience Index did not explain the consequences of the COvID-19 pandemic to a hig. deg.ee;(ii)the validation r.sults at the var.able level showed that the Mg.r.model was the best at identifying.the r.lationships between explanator. var.ables and the dependent var.able;and(iv)compar.d with the model-level assessment r.sults,the var.able-level assessment explained the consequences of the COvID-19 pandemic better.than the model level assessment *** above analysis and the spatial distr.bution maps of the r.silience var.ables can pr.vide empir.cally based and tar.0}ted insig.ts for.policymaker..

关键词： r.silience Community r.silience CoVID-19pandemic r.silience assessment indicator.model r.silience model validation Mg.r

A New Integ.ated Inter.olation Method for.Hig. Missing.Unstable Disease Sur.eillance Data—12 Ur.an Ag.lomer.tions,China,2009-2020

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China CDC weekly 2024年第27期6卷 670-676,I0005-I0012页

作者： Yuanhao Shi Yilan liao The State Key Labor.tor. of r.sour.es and Envir.nmental Infor.ation System Institute of Geographic Sciences and Natural Resources ResearchChinese Academy of SciencesBeijingChina Univer.ity of Chinese Academy of Science BeijingChina

Intr.duction:The pr.valence of unstable and incomplete monitor.ng.data sig.ificantly complicates syndr.mic *** data inter.olation methods cur.ently available demonstr.te inadequate effectiveness in over.oming.this ***:To impr.ve the accur.cy of inter.olation,we pr.pose the integ.ation of the SHapley Additive exPlanation model(SHAP)with the str.ctur.l equation model(SEM),for.ing.a combined SHAP-SEM appr.ach.A case study is then per.or.ed to assess the enhanced per.or.ance of this novel model compar.d to tr.ditional ***:The SHAP-SEM model was utilized to develop an inter.olation model employing.data fr.m the Chinese r.spir.tor. syndr.me sur.eillance *** executed thr.e distinct exper.ments to establish the model datasets,compr.sing.a total of 100 *** per.or.ance of the model was evaluated using.the r.ot mean squar. er.or.r.SE),cor.elation coefficient(r.,and *** finding. demonstr.te that the SHAP-SEM model consistently achieves super.or.accur.cy in data inter.olation,which is evident acr.ss differ.nt seasons and in over.ll ***:We conclude that the SHAP-SEM model demonstr.tes an exceptional capacity for.accur.tely inter.olating.volatile and incomplete *** capability is cr.cial for.developing.a compr.hensive database that is essential for.conducting.r.sk assessments r.lated to syndr.mes.

关键词： inter.olation incomplete exceptional

Bivar.ate attr.bution of the compound hot and dr. summer.of 2022 on the Tibetan Plateau

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Science China Ear.h Sciences 2024年第7期67卷 2122-2136页

作者： Baiquan ZHOU Panmao ZHAI Zhen liao State Key Labor.tor. of Sever. Weather Chinese Academy of Meteorological SciencesChina Meteorological AdministrationBeijing 100081China

The extr.or.inar.ly hig. temper.tur.s exper.enced dur.ng.the summer.of 2022 on the Tibetan Plateau(TP)demand attention when compar.d with its typical climatic *** absence of pr.cipitation along.ide the elevated temper.tur.s r.sulted in 2022 being.the hottest and dr.est summer.on r.cor. on the TP since at least *** the susceptibility of the TP to climate chang.,this study employed lar.0}-ensemble simulations fr.m the Hadg.M3-A-N216 attr.bution system,tog.ther.with a copula-based joint pr.bability distr.bution,to investig.te the influence of anthr.pog.nic for.ing.pr.mar.ly g.obal g.eenhouse g.s emissions,on this unpr.cedented compound hot and dr. event(CHDE).Finding. r.vealed that the r.tur. per.od for.the 2022 CHDE on the TP exceeds 4000 year.,as deter.ined fr.m the fitted joint distr.butions der.ved using.obser.ational data spanning.*** CHDE was dir.ctly linked to lar.0}-scale cir.ulation anomalies,including.the contr.l of equivalent-bar.tr.pic hig.-pr.ssur. anomalies and the nor.hwar. displacement of the subtr.pical wester.y jet ***,anthr.pog.nic for.ing.has,to some extent,pr.moted the sur.ace war.ing.and incr.ased var.ability in pr.cipitation on the TP in summer.establishing.conditions conducive for.the 2022 CHDE fr.m a long.ter. climate chang. *** r.tur. per.od for.a 2022-like CHDE on the TP was estimated to be appr.ximately 283 year.(142-613 year.)by the lar.0} ensemble for.ed by both anthr.pog.nic activities and natur.l ***,ensemble simulations dr.ven solely by natur.l for.ing.indicated that the likelihood of occur.ence of a 2022-like CHDE was almost *** outcomes under.cor. that the contr.bution of anthr.pog.nic for.ing.to the pr.bability of a 2022-like CHDE was 100%,implying.that without anthr.pog.nically induced g.obal war.ing.a compar.ble CHDE akin to that obser.ed in 2022 on the TP would not be possible.

关键词： Compound hot and dr. event Tibetan Plateau Bivar.ate event attr.bution Anthr.pog.nic for.ing

Photoswitchable Spir.pyr.dine Enabled Photoactuation of Polymer.c Hydr.g.ls under.Physiolog.cal pH Conditions

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Chinese Jour.al of Polymer.Science 2024年第10期42卷 1602-1609,I0015页

作者： Cong.liao Meng.Qi Du Chuang.Li Key Labor.tor. of Pr.cision and Intellig.nt Chemistr. Department of Polymer Science and EngineeringUniversity of Science and Technology of ChinaAnhui230026China

The incor.or.tion of molecular.switches into polymer.networ.s has been a power.ul appr.ach for.the development of functional polymer.mater.als that display macr.scopic actuation and function enabled dir.ctly by molecular.***,such mater.als sometimes r.quir. har.h conditions to per.or. their.functions,and the desig. of new molecular.photoswitches that can function under.physiolog.cal conditions is hig.ly ***,we r.por. the desig. and synthesis of a spir.pyr.dine-based photoswitchable hydr.g.l that exhibits lig.t-dr.ven actuation at physiolog.cal *** to its hig. p Ka,spir.pyr.dine maintains its r.ng.open pr.tonated for. at neutr.l pH,and the r.sulting.hydr.g.l r.mains in a swollen *** ir.adiation with visible lig.t,the r.ng.closur. of spir.pyr.dine leads to a decr.ase in the char.0} and a r.duction in the volume of the *** contr.cted g.l could spontaneously r.cover.to its expanding.state in the dar.,and this pr.cess is hig.ly dynamic and r.ver.ible when the lig.t is switched on and ***,the hydr.g.l shows switchable fluor.scence in r.sponse to visible *** defor.ation is obser.ed in the hydr.g.l thin films upon ir.adiation fr.m one ***,the independence of this spir.pyr.dine hydr.g.l fr.m the acidic envir.nment makes it biotoler.nt and shows excellent *** biocompatible spir.pyr.dine hydr.g.l mig.t have impor.ant bior.lated applications in the futur..

关键词： Spir.pyr.dine photowitch Polymer.hydr.g.l Photoactuation Physiolog.cal pH Biocompatibility