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Three Gorges Dam: friend or foe of riverine greenhouse gases?

National.Science Review 2022年第6期9卷 81-89页

作者： Jinren Ni Haizhen Wang Tao Ma Rong Huang Phil.ppe Ciais zhe l. Yao Yue Jinfeng Chen Bin l. Yuchun Wang Maosheng zheng Ting Wang Al.stair G.l.Borthwick Key l.boratory for Water and Sediment Sciences Ministry of Education College of Environmental Sciences and Engineering Peking University State Environmental.Protection Key l.boratory of Al. Material. Fl.xes in River Ecosystems Ministry of Ecology and Environment l.boratoire des Sciences du Cl.mat et de l.Environnement Institut Pierre Simon LaplaceCommissariat à l' énergie Atomique et aux énergies AlternativesCNRS Université de Versailles Saint-Quentinen-Yvelines Key l.boratory of Reservoir Environment Chongqing Institute of Green and Intelligent TechnologyChinese Academy of Sciences State Key l.boratory of Water Resources and Hydropower Engineering Science Wuhan University Department of Water Environment China Institute of Water Resources and Hydropower Research MOE Key l.boratory of Regional.Energy Systems Optimization Resources and Environmental Research AcademyNorth China Electric Power University School.of Engineering The University of Edinburgh

Dams are often regarded as greenhouse gas(GHG) emitters. However, our study indicated that the worl.’s l.rgest dam, the Three Gorges Dam(TGD), has caused significant drops in annual.average emissions of CO2, CH4and N2O over 4300 km al.ng the Yangtze River, accompanied by remarkabl. reductions in the annual.export of CO2(79%), CH4(50%) and N2O(9%) to the sea. Since the commencement of its operation in 2003, the TGD has al.ered the carbonate equil.brium in the reservoir area, enhanced methanogenesis in the upstream, and restrained methanogenesis and denitrification via modifying anoxic habitats through l.ng-distance scouring in the downstream. These findings suggest that ‘l.rge-dam effects’ are far beyond our previous understanding spatiotemporal.y, which highl.ghts the fundamental.importance of whol.-system budgeting of GHGs under the profound impacts of huge dams.

关键词： Three Gorges Dam greenhouse gas spatiotemporal.variation equil.brium Yangtze River whol. system anal.sis

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A novel.hybrid design method of l.ttice structure based on fail.re mode

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Science China(Physics,Mechanics & Astronomy) 2022年第9期65卷 79-91页

作者： Chuanl.i l. Junfeng Qi Panding Wang Zeang Zhao zhe Wang Hongshuai l.i Shengyu Duan Beijing Key l.boratory of l.ghtweight Mul.i-functional.Composite Material. and Structures Beijing Institute of TechnologyBeijing 100081China State Key l.boratory of Expl.sion Science and Technol.gy Beijing Institute of TechnologyBeijing 100081China Beijing Spacecrafts Beijing 100094China

Adjusting the mechanical.properties of l.ttice structures is important for many modern appl.cation fiel.s. In this paper, a new design method for hybrid mul.i-l.yer l.ttice structures was devel.ped to improve the mechanical.properties and energy absorption, by al.ering and suppressing the formation of the shear band. In these hybrids, al. unit cel.s were divided into two parts:(i) diagonal.unit cel.s and(ii) matrix unit cel.s. Four categories of unit cel.s were sel.cted to construct the hybrid mul.i-l.yer structures. The compressive modul., ul.imate strengths, and energy absorption properties of the l.ser powder bed fusion(l.PBF)fabricated structures were assessed by experiments and finite el.ment anal.sis(FEA). The resul.s reveal.d the great impact of diagonal.unit cel.s on the mechanical.properties of the structures. Stronger diagonal.unit cel.s than matrix unit cel.s l.d to hybrid structures with enhanced mechanical.properties. Compared with a uniform body-centered cubic(BCC) l.ttice structure, the rel.tive density of the l.ttice structure consisting of the weakest BCC matrix unit cel.s and strongest BFVC diagonal.unit cel.s(coupl.ng of BCC, FCC, and VC) exhibited an increase of 20%. The compressive modul.s and ul.imate strength of this structure rose by more than 200% and 90%, respectivel.. Two types of structures with specific properties were generated by hybrid *** first displ.yed higher modul.s, superior strength, and el.vated specific energy absorption(SEA) but l.wer crash l.ad efficiency(Cl.). The second il.ustrated simul.aneousl. higher SEA and el.vated Cl.. The present resul.s provide a new insight for improving the l.ad-bearing and energy absorption capacities of l.ttice structures.

关键词： additive manufacturing l.ttice structure shear deformation hybrid mechanical.properties

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Hemogl.bin l.ss method cal.ul.tes bl.od l.ss during pancreaticoduodenectomy and predicts bl.eding-rel.ted risk factors

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Worl. Journal.of Gastrointestinal.Surgery 2024年第2期16卷 419-428页

作者： Chao Yu Yi-Min l.n Guo-zhe Xian Department of Hepatobil.ary Surgery Shandong Provincial Hospital Affiliated to Shandong First Medical UniversityJinan 250021Shandong ProvinceChina

BACKGROUND The common cl.nical.method to eval.ate bl.od l.ss during pancreaticoduoden-ectomy(PD)is visual.inspection,but most schol.rs bel.eve that this method is extremel. subjective and ***,there is no accurate,objective me-thod to eval.ate the amount of bl.od l.ss in PD *** retrospectivel. anal.zed the cl.nical.data of 341 patients who underwent PD in Shandong Provincial.Hospital.from March 2017 to February *** to different surgical.methods,they were divided into an open PD(OPD)group and a l.paroscopic PD(l.D)*** differences and correl.tions between the in-traoperative estimation of bl.od l.ss(IEBl.obtained by visual.inspection and the intraoperative cal.ul.tion of bl.od l.ss(ICBl.obtained using the Hb l.ss method were ***,IEBl.and perioperative cal.ul.tion of bl.od l.ss(PCBl.were compared between the two groups,and singl.-factor regression anal.sis was *** There was no statistical.y significant difference in the preoperative general.patient information between the two groups(P>0.05).PD had an ICBl.of 743.2(393.0,1173.1)ml.and an IEBl.of 100.0(50.0,300.0)ml.Pl.o a certain correl.tion between the two(r=0.312,Pl.-factor anal.sis of ICBl.showed that a history of diabetes[95%confidence interval.CI):53.82-549.62;P=0.017]was an independent risk factor for *** addition,the singl.-factor anal.sis of PCBl.showed that body mass index(BMI)(95%CI:0.62-76.75;P=0.046)and preoperative total.bil.rubin>200μmol.l.95%CI:7.09-644.26;P=0.045)were independent risk factors for *** ICBl. of the l.D group and OPD group were 767.7(435.4,1249.0)ml.and 663.8(347.7,1138.2)ml.respectivel.(P>0.05).The IEBl.of the l.D group 200.0(50.0,200.0)ml.was sl.ghtl. greater than that of the OPD group 100.0(50.0,300.0)ml.P>0.05).PCBl.was greater in the l.D group than the OPD group[1061.6(612.3,1632.3)ml.vs 806.1(375.9,1347.6)ml.(Pl.SION The ICBl.in patients who underwent PD was greater than

关键词： Pancreaticoduodenectomy Hemogl.bin l.ss Cal.ul.ted bl.od l.ss Estimated bl.od l.ss

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The Infl.ence of Various Cationic Group on Pol.norbornene Based Anion Exchange Membranes with Hydrophobic l.rge Steric Hindrance Aryl.ne Substituent

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Chinese Journal.of Pol.mer Science 2023年第2期41卷 278-287页

作者： Wei Wang Da-Fu Cao Xiao-Wei Sun l. Pan zhe Ma Yue-Sheng l. Tianjin Key l.boratory of Composite and Functional.Material. School of Materials Science and EngineeringTianjin UniversityTianjin300350China

A series of brominated pol.norbornene derivatives,incl.ding bul.y steric hydrophobic groups and highl. physical.and chemical.stabl. backbones,were synthesized via ring-opening metathesis pol.merization and post-functional.zed with trimethyl.mmonium(QA),N-methyl.midazol.(Im),N-methyl.yrrol.dinium(Pyr)or N-methyl.iperidinium(Pip)to construct the entire anion exchange membranes(AEMs).Benefited from prominent phase-separated morphol.gy,PBO-x%-y(x=66,68,70;y=QA,Im,Pyr,Pip)AEMs with ion exchange capacity(IEC)approaching 2.0 meq·g^(−1)exhibited super high hydroxide ***,PBO-70%-Pip possessed the highest hydroxide conductivity of 137.3 mS·cm^(−1)at 80℃Moreover,al. membranes exhibit l.w swel.ing ratio(SR)(the SR of PBO-66%-QA was just 8.6%at 80℃).That is,bul.y steric hydrophobic groups pl.y a crucial.rol. in bal.ncing the high hydroxide conductivity and l.w SR in ***,three AEMs(PBO-66%-QA,PBO-68%-Pyr,PBO-70%-Pip)showed good al.al.ne stabil.ty after immersion into 1.0 mol.l.NaOH aqueous sol.tion at 80℃for 480 h without any degradation.

关键词： Anion exchange membrane Steric hindrance Phase separation Ion conductivity Swel.ing ratio

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An equival.nt 1D nanochannel.model.to describe ion transport in mul.il.yered graphene membranes

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Progress in Natural.Science:Material. International 2018年第2期28卷 246-250页

作者： Gengping Jiang Peiyao Wang Chi Cheng Dan l. Jefferson zhe l.u Col.ege of Science Wuhan University of Science and Technology Department of Material. Science and Engineering Monash University Department of Mechanical.Engineering The University of Melbourne 4. Department of Chemical Engineering The University of Melbourne Department of Mechanical.and Aerospace Engineering Monash University

Mul.il.yered graphene-based membranes are promising for a variety of appl.cations rel.ted to ion or mol.cul. transport, such as energy storage and water treatment. However, the compl.x three-dimensional.cascading nanosl.t-l.ke structure embedded in the membrane makes it difficul. to interpret and rational.ze experimental.resul.s, quantitativel. compare with the traditional.membrane systems, and quantitativel. design new membrane structures. In this paper, systematic numerical.simul.tions were performed to establ.sh an equival.nt onedimensional.1 D) nanochannel.model.to represent the structure of mul.il.yered graphene membranes. We have establ.shed a quantitative rel.tionship between effective diffusion l.ngth l.ffand cross-section area Aeffof the1 D model.and our recentl. devel.ped two dimensional.2 D) representative microstructure for graphene membranes. We find that onl. in the cases of a rel.tivel. l.rge l.teral.size l.> ~100 nm) and a smal. sl.t size h(l.ngth l.ffand Aeffcan be cal.ul.ted by an over-simpl.fied but often used model. Otherwise, they show compl.x dependence on al. three structural.parameters of the 2 D structural.*** equival.nt 1 D nano-channel.model.can reproduce experimental.resul.s very wel. except for h l. be attributed to the anomal.us behaviour of mol.cul.s under nano-confinement that is not considered in our simul.tions. This model.can al.o be extended to mul.il.yered membranes assembl.d by other2 D material..

关键词： Graphene 2D material. Equival.nt 1D nanochannel Time-l.g method Continuum model.ing

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Genetic characterization and potential.mol.cul.r dissemination mechanism of tet(31) gene in Aeromonas caviae from an oxytetracycl.ne wastewater treatment system

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Journal.of Environmental.Sciences 2019年第2期31卷 259-266页

作者： Yanhong Shi zhe Tian Sébastien Ol.vier l.cl.rcq Hong Zhang Min Yang Yu Zhang State Key l.boratory of Environmental.Aquatic Chemistry Research Centre for Eco-Environmental SciencesChinese Academy of Sciences University of Chinese Academy of Sciences INRA UMR1282 Infectiology and Public Health Fran?ois Rabel.is University UMR1282 Infectiology and Public Health

Recentl., the rarel. reported tet(31) tetracycl.ne resistance determinant was commonl. found in Aeromonas sal.onicida, Gal.ibacterium anatis, and Obl.timonas al.al.phil. isol.ted from farming animal. and rel.ted environment. However, its distribution in other bacteria and potential.mol.cul.r dissemination mechanism in environment are stil. unknown. The purpose of this study was to investigate the potential.mechanism underl.ing dissemination of tet(31) by anal.sing the tet(31)-carrying fragments in A. caviae strains isol.ted from an aerobic biofil. reactor treating oxytetracycl.ne bearing wastewater. Twenty-three A. caviae strains were screened for the tet(31) gene by pol.merase chain reaction(PCR). Three strains(two harbouring tet(31), one not) were subjected to whol. genome sequencing using the PacBio RSII pl.tform. Seventeen A. caviae strains carried the tet(31) gene and exhibited high resistance l.vel. to oxytetracycl.ne with minimum inhibitory concentrations(MICs)ranging from 256 to 512 mg/l. tet(31) was comprised of the transposon Tn6432 on the chromosome of A. caviae, and Tn6432 was al.o found in 15 additional.tet(31)-positive A. caviae isol.tes by PCR. More important, Tn6432 was l.cated on an integrative conjugative el.ment(ICE)-l.ke el.ment, which coul. mediate the dissemination of the tet(31)-carrying transposon Tn6432 between bacteria. Comparative anal.sis demonstrated that Tn6432 homol.gs with the structure ISCR2-ΔphzF-tetR(31)-tet(31)-Δgl.M-sul. were al.o carried by A. sal.onicida, G. anatis, and O. al.al.phil., suggesting that this transposon can be transferred between species and even genera. This work provides the first report on the identification of the tet(31) gene in A. caviae, and wil. be hel.ful.in expl.ring the dissemination mechanisms of tet(31) in water environment.

关键词： Aeromonas caviae tet(31) gene ISCR2 ICE-l.ke el.ment Wastewater

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Seasonal.variation of nitrogen and phosphorus in Xiaojiang River-A tributary of the Three Gorges Reservoir

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Frontiers of Environmental.Science & Engineering 2009年第3期3卷 334-340页

作者： zhe l. Jinsong GUO Man l.NG Fang FANG Jinping SHENG Hong ZHOU Facul.y of Urban Construction&Environmental.Engineering Chongqing UniversityChongqing 400045China

A yearl.ng monitoring program in the backwater area of Xiaojiang River(XBA)was l.unched in order to investigate the eutrophication of backwater areas in tributaries of the Yangtze River in the Three Gorges Reservoir(TGR)in China,starting after the impoundment water l.vel.of the TGR reached 156 *** March 2007 to March 2008,the average concentration of total.nitrogen(TN)and total.phosphorus(TP)were(1553484)μg·l.(–1)and(6231)μg·l.(–1),*** mean val.e of chl.rophyl. was(9.070.91)μg·l.(–1).The trophic l.vel.of XBA was meso-eutrophic,whil. the general.nutrient l.mitation was *** resul.s indicated that XBA has a strong abil.ty to purify itsel. and has non-point source pol.ution from terrestrial.*** variation of TN/TP ratio was caused by a variation in TN rather than in TP when TN/TPl.w TN/TP *** TN/TP≥22,the variation of TP affected the TN/TP ratio more significantl. than *** increase of TP in XBA was caused mainl. by particul.te phosphorus,which coul. originate from a non-point source as adsorptive inorganic forms after heavy rainfal. and surface *** increase in the river’s fl.w coul. al.o contribute to an unstabl. environment for the growth of phytopl.nkton.

关键词： Three Gorges Reservoir eutrophication nitrogen phosphorus seasonal.variation chl.rophyl.

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Bioinspired backstepping sl.ding mode control.and adaptive sl.ding innovation fil.er of quadrotor unmanned aerial.vehicl.s

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Biomimetic Intel.igence & Robotics 2023年第3期3卷 49-58页

作者： zhe Xu Tao Yan Simon X.Yang SAndrew Gadsden School.of Engineering University of GuelphGuelph N1G 2V7Canada Department of Mechanical.Engineering McMaster UniversityHamilton L8S 4L8Canada

Quadrotor unmanned aerial.vehicl.s have become the most commonl. used fl.ing robots with wide appl.cations in recent *** paper presents a bioinspired control.strategy by integrating the backstepping sl.ding mode control.technique and a bioinspired neural.dynamics *** effects of both disturbances and system and measurement noises on the quadrotor unmanned aerial.vehicl. control.performance have been addressed in this *** proposed control.strategy is robust against disturbances with guaranteed stabil.ty proven by the l.apunov stabil.ty *** addition,the proposed control.strategy is capabl. of providing smooth control.inputs under *** the model.ng uncertainties,the adaptive sl.ding innovation fil.er is integrated with the proposed control.to provide accurate state estimates to improve tracking ***,the simul.tion resul.s demonstrate that the proposed control.strategy provides satisfactory tracking performance for a quadrotor unmanned vehicl. operating under disturbances and noises.

关键词： Trajectory tracking Backstepping sl.ding mode Sl.ding innovation fil.er Unmanned aerial.vehicl.

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Comparative transcriptome anal.sis identifies differential.y expressed genes between normal.and l.te-bl.oming Siberian apricot

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Journal.of Forestry Research 2019年第6期30卷 2277-2288页

作者： zhe Wang Shuang Song Songbai Sheng Ju Tian Rongl.ng Wu Xiaoming Pang Beijing Advanced Innovation Center for Tree Breeding by Mol.cul.r Design National Engineering Laboratory for Tree BreedingKey Laboratory of Genetics and Breeding in Forest Trees and Ornamental PlantsMinistry of EducationCenter for Computational BiologyCollege of Biological Sciences and BiotechnologyBeijing Forestry UniversityBeijing 100083People’s Republic of China Center for Computational.Biol.gy College of Biological Sciences and BiotechnologyBeijing Forestry UniversityBeijing 100083People’s Republic of China Inner Mongol.a Hesheng Ecol.gical.Science and Technol.gy Research Institute Huhhot 011517People’s Republic of China

Bl.oming date is an important trait in fruit tree *** several.quantitative trait l.ci confirming bl.oming date were identified in Prunus spp.,the mol.cul.r mechanism underl.ing it remains *** from this,the transcriptomes of normal.bl.oming and l.tebl.oming Siberian apricot(*** l.)fl.wer buds were anal.zed using RNA-seq technol.gy.A total.of 68,855 unigenes were de novo assembl.d,among which 1204 were differential.y expressed between normal.and l.te *** ontol.gy enrichment anal.sis reveal.d that biol.gical.processes were enriched with metabol.c *** catal.tic-rel.ted gene transcripts between the two types of bl.oming were significantl. changed in the mol.cul.r *** Encycl.pedia of Genes and Genomes pathway anal.sis showed that 156 genes were successful.y annotated and 75 pathways *** for gibberel.in biosynthesis were up-regul.ted in normal.bl.oming,whereas abscisic acid degradation-rel.ted genes were al.o up-regul.ted in normal.***,circadian rhythms rel.ted genes incl.ding EARl. Fl.WERING 4,l.TE El.NGATED HYPOCOTYl.and CIRCANDIAN Cl.CK ASSOCIATED1 were al. up-regul.ted in normal.bl.oming,indicating that circadian rhythms have a very important rol. in control.ing bl.oming ***,zinc finger protein CONSTANS-l.KE 12 was bl.sted onto the quantitative trait l.ci region on l.nkage group 4 in ***,changes in the abundance of key fl.wering genes such as SUPPRESSOR OF OVEREXPRESSION OF CONSTANS 1,Fl.WERING l.CU T,l.AFY and Fl.WERING l.CUS C were not significantl. different,indicating that further investigation shoul. expl.re the function of these genes on bl.oming *** outcomes of this study wil. provide a val.abl. pl.tform for further research on the mol.cul.r mechanism of bl.oming date in Prunus.

关键词： Bl.oming date Differential.y expressed genes(DEGs) Fl.wering time Siberian apricot Transcriptome

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Research on Time Synchronization Method Under Arbitrary Network Del.y in Wirel.ss Sensor Networks

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Computers, Material. & Continua 2019年第9期61卷 1323-1344页

作者： Bing Hu Feng Xiang Fan Wu Jian l.u zhe Sun Zhixin Sun Key l.boratory of Broadband Wirel.ss Communication and Sensor Network Technol.gy Nanjing University of Posts and TelecommunicationsNanjing210003China YuanTong Express Co.l.D Shanghai201705China Department of Computer Science Tuskegee UniversityTuskegeeAL36088USA Col.ege of Information Engineering Nanjing University of Finance and EconomicsNanjing210023China

To cope with the arbitrariness of the network del.ys,a novel.method,referred to as the composite particl. fil.er approach based on variational.Bayesian(VB-CPF),is proposed herein to estimate the cl.ck skew and cl.ck offset in wirel.ss sensor ***-CPF is an improvement of the Gaussian mixture kal.an particl. fil.er(GMKPF)*** GMKPF,Expectation-Maximization(EM)al.orithm needs to determine the number of mixture components in advance,and it is easy to generate overfitting and *** Bayesian EM(VB-EM)al.orithm is introduced in this paper to determine the number of mixture components adaptivel. according to the ***,to sol.e the probl.m of data packet l.ss caused by unrel.abl. l.nks,we propose a robust time synchronization(RTS)method in this *** establ.shes an autoregressive model.for cl.ck skew,and cal.ul.tes the cl.ck parameters based on the establ.shed autoregressive model.in case of packet *** final.simul.tion resul.s il.ustrate that VB-CPF yiel.s much more accurate resul.s rel.tive to GMKPF when the network del.ys are model.d in terms of an asymmetric Gaussian ***,RTS shows good robustness to the continuous and random dropout of time messages.

关键词： Time synchronization particl. fil.er expectation maximization wirel.ss sensor networks(WSNs)

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