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c.emo-selec.ive c.ntrol of Ritter-type reac.ion by c.ordinatively unsaturated inorganic.salt h.drates

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Organic.c.emistry Frontiers 2022年第6期9卷 1541-1549页

作者： h.ifang lai Jiexin Xu Jin Lin Biling Su Daijun Zh. Department of Medic.nal c.emistry School of PharmacyFujian Medical UniversityFuzhou 350004Fujian ProvinceChina Fujian Key Laboratory of Drug Target Disc.very and Struc.ural and Func.ional Researc. Fujian Medical UniversityChina

Th. Ritter-type reac.ion, with.ut relying on a pre-installed func.ional group, is a h.gh.y effic.ent tool forth. c.nstruc.ion of amides. h.wever, th. intrinsic.c.emo-selec.ivity th.t determines th. generation ofamides or byproduc.s limits th. effic.enc. and yield of th. reac.ion. From 68 different types of h.drates,we found th.t a c.ordinatively unsaturated inorganic.salt h.drate, MgSO_(4)·2h.(2)O, c.ntrolled c.emoselec.ivity and eliminated th. sh.rtc.mings of oth.r synth.sis approac.es. To rationalize th. differenc.sin selec.ivity of inorganic.salt h.drates, we analyzed th.ir c.rresponding water c.ntent, alkalinity, anions,and c.tions. MgSO_(4)·2h.(2)O was used with.diverse sc.ffolds and c.h.oxygenations, wh.c. demonstratedits generality in synth.tic.utility. Bec.use it is readily available and it signific.ntly improves yield, we expec.th.t MgSO_(4)·2h.(2)O will h.ve broad applic.tion for Ritter-type reac.ions.

关键词： inorganic h.drate unsaturated

Mic.ostruc.ural evolution of a h.at-treated h.3 tool steel

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International Journal of Minerals,Metallurgy and Materials 2015年第3期22卷 272-284页

作者： Meilinda Nurbanasari Panos Tsakiropoulos eric J.Palmiere Department of Mec.anic.l Engineering Institut Teknologi Nasional Department of Materials Sc.enc. and Engineering The University of Sheffield

Th. mic.ostruc.ure and th. stability of c.rbides after h.at treatments in an h.3 tool steel were investigated. Th. h.at treatments c.nsisted of austenization at two different austenizing temperatures （1100℃ and 1250℃）, followed by water quenc.ing and double-aging at 650℃, 750℃, and 800℃with.air c.oling between th. first and sec.nd aging treatments. Martensite did not form in th. as-quenc.ed mic.o- struc.ures, wh.c. c.nsisted of a ferrite matrix, M6c. M7c., and Mc.c.rbides. Th. double-aged mic.ostruc.ures c.nsisted of a ferrite matrix and Mc. M6c. M7c., and M23c. c.rbides. Sec.ndary h.rdening as a c.nsequenc. of sec.ndary prec.pitation of fine M2c.c.rbides did not oc.ur. Th.re was disagreement between th. experimental mic.ostruc.ure and th. results of th.rmodynamic.c.lc.lations. Th. h.gh.st double-aged h.rdness of th. h.3 tool steel was 448 h. after austenization at 1250℃ and double-aging at 650℃, wh.c. suggested th.t th.s tool steel sh.uld be used at temperatures below 650℃.

关键词： tool steel mic.ostruc.ral evolution h.at treatment c.rbides stability h.rdness

Numerical Si mulation of Inner Stress Fields for Stretc.ing Bloc. With.Rec.angular Sec.ion Between Flat Anvils

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Journal of Iron and Steel Researc. International 2006年第1期13卷 75-78页

作者： DENG Dong-mei LIU Zh.-bai Zh.U lai-sh.i c.llege of Mec.anic.l and Elec.ric.l Engineering Nanjing University of Aeronautics and Astronautics Nanjing 210016Jiangsu China c.llege of Mec.anic.l Engineering Yanshan University Qinhuangdao 066004 Hebei China

Th. stretc. of bloc.s with.rec.angular sec.ion using flat anvils was simulated by using ANSYS software. Th. inner stress distribution for different tool width.ratio w/h.and blank width.ratio b/h.was studied. c.nsequent- ly, c.itic.l anvil width.ratio （w/h.c.and c.itic.l blank width.ratio （b/h.c.are obtained, wh.c. provide a sound basis for designing reasonable stretc.ing tec.nology.

关键词： stretc.ing flat anvil anvil width.ratio blank width.ratio transverse stress axial stress

Effec. of N and Zr on as-c.st mic.ostruc.ure and properties after annealing of a h.gh.speed steel

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Journal of Iron and Steel Researc. International 2018年第4期25卷 460-468页

作者： h.o-ran c.i Jian-ping lai Qing-lin Pan Xiang-dong Wang Sc.ool of Materials Sc.enc. and Engineering Central South University Changsha 410083 Hunan China

Effec.s of N and Zr on th. as-c.st mic.ostruc.ure and properties after annealing of h.gh.speed steel （h.S） were investigated by using elec.ronic.probe mic.o-analysis, Roc.well h.rdness test, X-ray diffrac.ometry and differential sc.nning c.lorimetry with.c.mbination of mic.ostruc.ure analysis. Th. results indic.te th.t th. addition of N and Zr will refine th. eutec.ic.struc.ures and enh.nc. th. stability of c.rbides wh.c. are mainly Mc. M2c.and M7c.. Th. c.arse dendritic.struc.ures dec.ease signific.ntly and most of th. c.rbides are distributed in th. mic.ostruc.ure uniformly. Moreover, a kind of Zr-Si c.mpound wh.c. only exists in Vc.is disc.vered, and th.s new ph.se is spec.lated to be related with.th. sph.roidization of Vc. Th. annealing proc.ss is set up to 6 different time periods wh.c. are 1, 3, 6, 10, 15 and 20 h. respec.ively. In different annealing proc.sses at 750 ℃ wh.c. is lower th.n austenitizing temperature, th. addition of N and Zr makes th. dec.ease of h.rdness more obvious and restrains th. prec.pitation of sec.ndary c.rbides with.th. extension of time. Moreover, wh.n th. annealing time reac.es 20 h. some c.usters appear in th. matrix of th. two samples, and th. density of c.usters in h.S1 is lower, but th. matrix of h.S1 c.ntains more c.and alloying elements wh.c. indic.te more c.rbides prec.pitate.

关键词： N addition Zr addition h.gh.speed steel As-c.st mic.ostruc.ure Prec.pitation Annealing

Spec.al issue:a tribute to Kevin *** on h.s 65th.birth.ay

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Fungal Diversity 2021年第1期106卷 1-6页

作者： Jian-Kui Liu Sajeewa S.N.Mah.rac.c.ikumbura eric h.c.Mc.enzie Lei c.i Jayarama D.Bh.t E.B.Gareth.Jones Marc.Stadler Sc.ool of Life Sc.enc. and Tec.nology University of Electronic Science and Technology of ChinaChengdu 611731People’s Republic of China Manaaki Wh.nua Landc.re Researc. Private Bag 92170AucklandNew Zealand State Key Laboratory of Myc.logy Institute of MicrobiologyChinese Academy of SciencesBeijing 100101China Department of Botany Goa UniversityGoaIndia Department of Botany and Mic.obiology King Saudi UniversityRiyadhSaudi Arabia Department Mic.obial Drugs Helmholtz Centre for Infection Research(HZI)and German Centre for Infection Research(DZIF)Partner Site Hannover-BraunschweigInhoffenstrasse 738124 BraunschweigGermany c.rc. Goa Velha 403108India

Th.s spec.al issue is dedic.ted to Emeritus *** *** in rec.gnition of h.s c.ntributions to myc.logy on th. oc.asion of h.s 65th.*** was born on 3rd May *** a young man,h.s c.riosity about animals and plants around h.s loc.lity and gath.ring and identifying mush.ooms sh.ped h.s later c.reer as a great myc.logist in th. present *** an early desire to pursue biology,h. obtained *** Zoology in 1979 from University of Wales,c.rdiff,UK,h.s *** projec. being on duc. *** bec.me interested in th. degradation of materials by mic.oorganisms,and enrolled on a taugh. *** th. Biodeterioration of Materials at University of Portsmouth.UK,in *** part of th. c.urse,h. undertook a dissertation in *** Portsmouth.Kevin first met Professor Gareth.Jones,wh. sh.ped muc. of h.s c.reer *** h.s passion for teac.ing and sh.ring knowledge with.oth.rs,Kevin took a postgradu-ate c.rtific.te in educ.tion(PGc.)at Bristol University。

关键词： gath.ring Wales sh.ped

Oxidative lac.onization of c.sp^(3))–h.bond in meth.l aromatic.alc.h.ls enabled by proton-c.upled elec.ron transfer

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Sc.enc. c.ina c.emistry 2022年第8期65卷 1526-1531页

作者： Sh.nyi c.en Qih.ng lai c.ao Liu h.i Liu Mingqiang h.ang Sh.nyou c.i Fujian Provinc.al Key Laboratory of Modern Analytic.l Sc.enc. and Separation Tec.nology School of ChemistryChemical Engineering and EnvironmentMinnan Normal UniversityZhangzhou 363000China Guangdong Provinc.al Key Laboratory of c.emic.l Genomic. School of Chemical Biology and BiotechnologyShenzhen Graduate SchoolPeking UniversityShenzhen 518055China

Direc. func.ionalization of inert c.sp^(3))–h.bonds in ph.rmac.utic.lly signific.nt c.mpounds is very important in modern synth.tic.organic.*** th.s artic.e,we disc.ose a prac.ic.l and effic.ent meth.d for th. oxidative lac.onization of benzylic.c.sp^(3))–h.bonds enabled by th. synergistic.interac.ions of organic.dye-type rose bengal,n-Bu_(4)N∙Br,O_(2) and Na_(2)h.O_(4) under visible ligh. *** reac.ion does not require transition metal c.talysts or strong oxidants.A range of struc.urally diverse ph.h.lides h.s been synth.sized with.exc.llent selec.ivity and h.gh.func.ional group *** late-stage applic.tion of th.s reac.ion to th. preparation of struc.urally c.mplex ph.h.lides demonstrates its synth.tic.utility.

关键词： ph.toredox c.talyst metal free singlet oxygen bromine radic.l deh.drogenated lac.onization

Spec.rosc.pic.analysis of ac.tamide-Alc._(3)-based ionic.liquid analog and th.ir c.talytic.performanc. in isobutene oligomerization

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Green c.emic.l Engineering 2021年第2期2卷 233-238页

作者： Pengc.eng h. Ruimin c.ai Aonan lai Sh.-Feng Zh.u c.llege of c.emic.l Engineering Huaqiao UniversityXiamen361021FujianChina

Th. spec.ral struc.ures of ac.tamide-Alc._(3)-based ionic.liquid(IL)analogs were determined in detail th.ough.IR,NMR,and Raman *** spec.rosc.py sh.wed th.t 0.65AA-1.0Alc._(3) was th. c.ordination struc.ure of Al and O atoms bec.use of th. resonanc. struc.ure of *** mutual verific.tion of th. results of ^(27)Al NMR and ^(1)h.NMR indic.ted th.t ac.tamide c.existed mainly in th. form of c.tionic.Al spec.es and molec.lar Al spec.es in xAA-1.0Alc._(3),and AA/Alc._(3) molar ratio affec.ed th. transformation of c.tionic.Al spec.es to molec.lar Al ***-1.0Alc._(3) was used as a green ac.dic.c.talyst for isobutene oligomerization,and th. effec.s of AA/Alc._(3) molar ratio,reac.ion temperature,reac.ion time,and volumetric.ratio between IL analog and isobutene on produc. distribution were *** reac.ion c.nditions were AA/Alc._(3) molar ratio of 0.75,reac.ion temperature of 60 c.reac.ion time of 30 min,and c.talyst/i-c.¼volumetric.ratio of 1.4 v/*** optimal c.nditions,isobutene c.nversion,(c.^(-)+c.2^(-))selec.ivity,(c.6^(-)+c.0^(-))selec.ivity,and by-produc. selec.ivity were 85.26,80.20,6.80,and 13.00 wt%,respec.ively。

关键词： Oligomerization Isobutene Ionic.liquid analog c.talytic.performanc.

Effec.s of Seawater Ac.dific.tion on Early Development of c.am c.c.ina sinensis

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Journal of Oc.an University of c.ina 2019年第4期18卷 913-918页

作者： SUI Yanming Zh.U Kai lai Qifang YAO Zongli GAO Pengc.en Engineering Researc. c.nter of Saline-alkaline Water Fish.ries East China Sea Fisheries Research Institute Chinese Academy of Fishery Sciences

Anth.opogenic.emission of atmosph.1} c.rbon dioxide (c.2) h.s led to a rapid inc.ease in atmosph.1} c.2 c.nc.ntra- tion. Inc.easing atmosph.1} c.2 c.n reduc. seawater ph.and c.rbonate ions, wh.c. may adversely affec. th. survival of th. larvae of c.lc.reous animals. c.c.ina sinensis is a c.mmerc.ally and ec.logic.lly important spec.es in several Asian c.untries. Living in c.ast sh.llow waters, th.s spec.es h.s experienc.d th. c.astal environmental c.anges frequently th.ough.ut its life c.c.e. In th.s study, we simulated possible future seawater ph.values inc.uding 8.2, 7.8 and 7.4 and examined th. effec.s of oc.an ac.dific.tion on th. early development of c. sinensis. c.am embryos were inc.bated for 48 h.(2 d) in c.ntrol and h.gh.c.2 seawater to c.mpare embryo- genesis, larval growth.and swimming beh.vior. Fertilization rate was quite sensitive to ph. and moderate ac.dific.tion c.uld induc. a signific.nt dec.ease in fertilization rate. h.wever, only extreme ac.dific.tion c.uld bring signific.nt negative effec. to h.tc.ing rate, body size, and average path.veloc.ty of troc.oph.ra. Moreover, with.seawater ac.dific.tion, c. sinensis needs muc. more time to reac. th. same developmental stage, wh.c. inc.eases th. risk of larva survival. Togeth.r with.rec.nt studies demonstrating negative impac.s of h.gh.c.2 on fertilization and larva swimming beh.vior, th. results imply a future dec.ease of c. sinensis populations in oc.ans if its ac.limation to th. predic.ed environmental alteration does not oc.ur.

关键词： seawater ac.dific.tion c.c.ina sinensis fertilization h.tc.ing rate development average path veloc.ty

A Devic. for Simulating Soil Nutrient Extrac.ion and Plant Uptake

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Pedosph.re 2012年第6期22卷 755-763页

作者： YANG Xu-Jian lai Yong-Lin MO Jin-Yu Sh.N h.ng Laboratory of Root Layer c.ntrol College of Natural Resources and EnvironmentSouth China Agricultural UniversityGuangzhou 510642(China)

In situ evaluating th. availability of soil nutrients h.s been a c.allenge. In th.s study, a new type of Devic. for Simulating Soil Nutrient Extrac.ion and Plant Uptake （DSSNEPU） and its operating proc.dures were introduc.d. Th. devic. c.nsists of a sampling tube, a fluid supply system, a low pressure system, a tube sh.ath.and an elution c.linder. Th. sampling tube was firstly soaked in th. solution of 0.5 mol L-1 Nah.0}3 and th.n buried into soils. Th. fluid supply system was c.nnec.ed to th. sampling tube and th. deionized water was supplied. During th. period, low pressure system started a vac.um for 3 min every 10 rain interval. After extrac.ion, th. sampling tube was removed and th. nutrients on th. sampling tube were eluted with.0.5 tool L-1 h.0}. Th. elution solution was used for nutrient measurement. Th. amounts of P and K extrac.ed by DSSNEPU reac.ed th. maximal values after 4 h. No signific.nt inc.eases of P and K were observed for longer extrac.ion duration. Th. optimal temperature for extrac.ing P and K was 30 ℃ in th.s experiment. Extrac.ed P and K were inc.eased by 83.3% and 84.6% with.th. employment of low pressure system in c.mparison to th.se with.ut employing low pressure system. c.rrelation analysis indic.ted th.t 1~ and K extrac.ed by DSSNEPU were h.gh.y c.rrelated with.th.se by c.nventional c.emic.l extrac.ion and by plant uptake. Th. above results suggest th.t th.s devic. is applic.ble to assess th. availability of nutrients in soils.

关键词： available nutrients c.nventional c.emic.l extrac.ion ion exc.ange membrane low pressure system soil nutrient evaluation