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Rare Metals 2019年第12期38卷 1124-1130页

作者： Ji-hui Luo Xue-Feng liu Zhang-Zhi Shi yi-Fei liu School of Materials Science and Engineering University of Science and Technology BeijingBeijing 100083China Beijing Laboratory of Metallic Materials and Processing for Modem Transportation University of Science and Technology BeijingBeijing 100083China

Microstructures of Cu-4.7Sn(%) alloys prepared by two-phase zone continuous casting(TZCC)technology contain large columnar grains and small grains.A compound grain structure,composed of a large columnar grain and at least one small grain within it,is observed and called as grain-covered grains(GCGs).Distribution of small grains,their numbers and sizes as well as numbers and sizes of columnar grains were characterized quantitatively by metallographic *** propagation(BP) artificial neural network was employed to build a model to predict microstructures produced by different processing *** of the model are five processing parameters,which are temperatures of melt,mold and cooling water,speed of TZCC,and cooling *** of the model are nine microstructure quantities,which are numbers of small grains within columnar grains,at the boundaries of the columnar grains,or at the surface of the alloy,the maximum and the minimum numbers of small grains within a columnar grain,numbers of columnar grains with or without small grains,and sizes of small grains and columnar *** model yields precise prediction,which lays foundation for controlling microstructures of alloys prepared by TZCC.

关键词： Two-phase zone continuous casting Cu-Sn alloy Grains-covered grains Microstructure quantification Back propagation artificial neural network

Pheromones emitted by both female and male moths regulate coordination between the sexes for Agriphila aeneociliella (Lepidoptera: Crambidae)

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Insect Science 2023年第5期30卷 1481-1492页

作者： yi-Di Zhan ying-Jie liu Jia-hui liu Yong liu College of Plant Protection Shandong Agricultural UniversityTaianShandong ProvinceChina Staff Development Institute of China National Tobacco Corporation ZhengzhouChina Functional and Evolutionary Entomology Gembloux Agro-Bio TechLiège UniversityGemblouxBelgium

The complex and efficient sex pheromone communication system in insects is essential for reproduction and for reproductive isolation of *** moths,sex pheromone communication starts with male attraction to compounds emitted by females;only a few species act in the ***,how the pheromones that are emitted by both sexes co-regulate and coordinate mate finding and mating remains ***,we identified both the male and female pheromones of Eastern Grass Veneer moth,Agriphila aeneociliella(Lepidoptera:Crambidae),and demonstrated their efficiency in manipulating behavioral responses of the opposite *** data from analysis of gas chromatography-electroantennogram detection,gas chromatography-mass spectrometry,and olfactory behavior assays,the female pheromone of *** was identified as(Z,Z,Z)-9,12,15-octadecatrienal and(Z)-9-hexadecenyl acetate,while the male pheromone was determined to be *** the 2 individual components of the female pheromone and their binary mixture were significantly attractive to males,and the 1-nonanal male pheromone induced strong electrophysiological responses in females and induced attraction of females in a Y-tube olfactory *** on the concentration of 1-nonanal,its addition to the binary mixture of the female pheromone either enhanced(10^(−3) or 10^(−2)μg/μL)or reduced(1μg/μL)the aphrodisiac effect of the mixture on *** wind-tunnel bioassays,different concentrations of pheromones,including the binary mixture of female pheromone and the mixture of male and female pheromones,had significant effects on male *** findings suggested that the blend of both female and male pheromones plays a significant role in the sexual communication system in some moths.

关键词： Crambidae male pheromone reproductive strategy sexual reproduction wheat pest

基于石墨烯电极TCNQ分子结热/电输运性质理论研究

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原子与分子物理学报 2025年第3期42卷 135-140页

作者：刘仪伟邱乙峰张蓓新疆大学物理科学与技术学院乌鲁木齐830046

本文采用密度泛函理论和非格林平衡函数,对基于石墨烯电极的7,7,8,8-四氰基苯醌二甲烷(Tetracyanoquinodimethane,TCNQ)分子结热/电输运性质进行系统研究.研究结果表明:随着中心TCNQ分子个数的增加,声子透射系数明显降低,即声子透射行... 详细信息

本文采用密度泛函理论和非格林平衡函数,对基于石墨烯电极的7,7,8,8-四氰基苯醌二甲烷(Tetracyanoquinodimethane,TCNQ)分子结热/电输运性质进行系统研究.研究结果表明:随着中心TCNQ分子个数的增加,声子透射系数明显降低,即声子透射行为受到极大抑制.与此同时,电子透射系数也有一定程度的减小.在热/电参数的协同作用下,伴随分子数量的增加分子结热电转换性能呈上升趋势,1TCNQ热电优值(ZT)为0.016,而2TCNQ则上升了1个数量级,ZT值达到0.11.最后,我们对分子结依赖于分子结构个数的自旋输运性质进行研究,发现TCNQ分子结具有显著的自旋过滤效应,其过滤能力随着TCNQ分子数量的增加而增加.该工作可为实验制备分子热电器件提供理论依据和数据支持.

关键词：锯齿状石墨烯纳米带 TCNQ分子自旋输运性质自旋过滤效应

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大深宽比矩形高层建筑表面脉动风压非高斯特性

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哈尔滨工业大学学报 2025年第1期57卷 46-55页

作者：袁家辉陈水福刘奕中冶南方城市建设工程技术有限公司武汉430063 浙江大学建筑工程学院杭州310058

为探究大深宽比矩形高层建筑表面脉动风压的非高斯特性,本文对深宽比为1/9~9的矩形高层建筑进行了同步测压风洞试验。基于试验结果,分析了建筑表面风压的三阶和四阶统计矩分布特性,对高层建筑各立面风压进行高斯与非高斯分布的分区;研... 详细信息

为探究大深宽比矩形高层建筑表面脉动风压的非高斯特性,本文对深宽比为1/9~9的矩形高层建筑进行了同步测压风洞试验。基于试验结果,分析了建筑表面风压的三阶和四阶统计矩分布特性,对高层建筑各立面风压进行高斯与非高斯分布的分区;研究了风压的空间相关系数与非高斯性强度的关系,提出了一种新的估算建筑侧风面平均再附长度的计算方法。结果表明:在建筑侧风面上,脉动风压服从高斯还是非高斯分布取决于测点到迎风前缘的距离;除了以往文献指出的迎风面角部、侧风面分离区和背风面风压呈现非高斯性外,再附区后面的风压也呈现出高度的非高斯性;本文提出的相关系数法在计算平均再附长度时具有良好的准确性,利用该方法获得了矩形高层建筑侧风面的平均再附长度沿高度的变化呈抛物线形状。

关键词：矩形高层建筑非高斯特性风洞试验相关系数平均再附长度

The gamma-ray Doppler factor determinations for a Fermi blazar sample

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Research in Astronomy and Astrophysics 2013年第3期13卷 259-269页

作者： Jun-hui Fan Jiang-He Yang yi liu Jing-yi Zhang Center for Astrophysics Guangzhou University Astronomy Science and Technology Research Laboratory of Department of Education of Guangdong Province Department of Physics and Electronics Science Hunan University of Arts and Science

Observations suggest that γ-ray loud blazars are strongly beamed. The Fermi mission has detected many of blazars, which provide us with a good opportunity to investigate the emission mechanism and the beaming effect in the γ-ray region. We compiled the X-ray observations for 138 Fermi blazars （54 flat spectrum radio quasars, 36 low-peaked BL Lacertae objects, and 48 high-peaked BL Lacertae objects） and calculated their Doppler factors, δγ. It is interesting that the calculated Doppler factors, δγ, are strongly correlated with the γ-ray luminosity.

关键词： galaxies: active -- galaxies: BL Lacertae objects -- galaxies: quasars --galaxies: jets

Incidence and risk factors of pancreatitis in obstructive jaundice patients after percutaneous placement of self-expandable metallic stents

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Hepatobiliary & Pancreatic Diseases International 2020年第5期19卷 473-477页

作者： yi Yang Rui-Bao liu Yan liu hui-Jie Jiang Department of Radiology the Second Affiliated Hospital of Harbin Medical UniversityHarbin 150086China Department of Interventional Radiology Harbin Medical University Cancer HospitalHarbin 150081China

Background:Percutaneous transhepatic biliary drainage is an alternative treatment for patients with malignant distal biliary *** aim of this study was to investigate the occurrence of pancreatitis in patients who had undergone percutaneous placement of a biliary stent and to assess the risk factors for pancreatitis and the treatment ***:From January 2010 to October 2016,980 patients in our hospital who underwent percutaneous placements of self-expandable metallic stents for obstructive jaundice were retrospectively *** incidence of pancreatitis and risk factors were assessed by univariate and multivariate logistic regression ***,such as somatostatin,which were also adminstrated to release the symptom and promote the restoration of normal function of pancreas,were also ***:Pancreatitis occurred in 45(4.6%)*** patient died from severe acute *** logistic regression analysis showed that common bile duct stent placement was the only independent risk factor that related to pancreatitis(odds ratio=2.096,95%CI:1.248–5.379;P=0.002).By using somatostatin,the concentrations of serum amylase and lipase were decreased in 44 patients with *** major complications were found during the ***:Pancreatitis is a relatively low complication of percutaneous placement of biliary *** common bile duct stent placement is the only independent risk factor that related to *** this case,the percutaneous transhepatic biliary drainage is a preferred method for ***,somatostatin is a secure and efficacious method to release the symptom and promote the restoration of pancreatic function.

关键词： Stents Obstructive jaundice Pancreatitis

Identification of winter long-lasting regional extreme low-temperature events in Eurasia and their variation during 1948—2017

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Advances in Climate Change Research 2021年第3期12卷 353-362页

作者： ZHANG ying-Xian liu Yan-Ju DING yi-hui Laboratory for Climate Studies National Climate CenterChina Meteorological AdministrationBeijing100081China

Compared with short-duration events,long-lasting regional extreme low-temperature events(RELTEs)often have more severe impacts on human societies due to the induced persistence and large geographic area of related weather and climate ***,an improved objective technique was applied to identify all long-lasting RELTEs in Eurasia from the winter of 1948/1949 to 2017/2018,followed by an in-depth discussion of its variation in terms of the annual frequency,duration,impacted area,mean intensity,maximum intensity,and a comprehensive *** RELTE lasting for 52 d in the winter of 2007/2008 exhibited the longest duration,largest impacted area,and a greatest comprehensive index,which induced extremely low temperatures for more than 20 d in Western Asia,Central Asia,and *** the past 70 winters,the frequency of long-lasting RELTEs decreased,especially after the late ***,the mean and maximum intensities and comprehensive index exhibited distinctly increasing *** indicators of winter long-lasting RELTEs had a similar inter-decadal fluctuation featured by two noticeable peaks occurring around 1970 and 2007,and a remarkable recovery was discovered in the period of late 1990s to mid-2010s,especially for the occurrence of super long-lasting ***,winter long-lasting RELTEs in Eurasia showed distinct trends under various decadal climate backgrounds,i.e.,a strong negative or weak positive trend in the accelerated warming period and conversely,a strong positive or weak negative trend in the wanning slowdown *** findings indicate that we should be alert of the similar future recovery of winter long-lasting RELTEs in Eurasia,which are likely to occur in the slowdown period of global warming.

关键词： Regional extreme low-temperature events Winter Long-lasting Eurasia Climate variation

Analysis of imbibition of n-alkanes in kerogen slits by molecular dynamics simulation for characterization of shale oil rocks

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Petroleum Science 2022年第3期19卷 1236-1249页

作者： Qian Sang Xin-yi Zhao hui-Min liu Ming-Zhe Dong Key Laboratory of Unconventional Oil&Gas Development(China University of Petroleum(East China)) Ministry of EducationQingdao266580ShandongChina School of Petroleum Engineering China University of Petroleum(East China)Qingdao266580ShandongChina Management Center of Oil&Gas Exploration of Shengli Oilfield Branch Company SINOPECDongying257001ShandongChina Department of Chemical and Petroleum Engineering University of CalgaryCalgaryABCanadaT2N 1N4

Shale oil formations contain both inorganic and organic *** organic matter holds both free oil in the pores and dissolved oil within the kerogen *** free oil flow in organic pores and the dissolved oil diffusion in kerogen molecules are coupled *** molecular flow of free n-alkanes is an important process of shale oil accumulation and *** study the dynamics of imbibition process of n-alkane molecules into kerogen slits,molecular dynamics(MD)simulations are *** of slit width,temperature,and n-alkane types on the penetration speed,dynamic contact angle,and molecular conformations were *** showed that molecular transportation of n-alkanes is dominated by molecular structure and molecular motion at this *** space-confinement conformational changes of molecules slow down the filling speeds in the narrow *** n-alkane molecules with long carbon chains require more time to undergo conformational *** high content of short-chain alkanes and high temperature facilitate the flow of alkane mixtures in kerogen *** obtained from this study are useful for understanding the underlying nanoscale flow mechanism in shale formations.

关键词： Molecular flow Imbibition n-Alkane Kerogen slit Molecular dynamics simulation

Trinuclear Dy(III)Single-Molecule Magnets with Two-Step Relaxation

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Chinese Journal of Chemistry 2023年第20期41卷 2641-2647页

作者： yi-Shu Jin Cai-Ming liu yi-Quan Zhang hui-Zhong Kou Engineering Research Center of Advanced Rare Earth Materials(Ministry of Education) Department of ChemistryTsinghua UniversityBeijing100084 China Beijing National Laboratory for Molecular Sciences Center for Molecular ScienceInstitute of ChemistryChinese Academy of SciencesBeijing100190 China Jiangsu Key Lab for NSLSCS School of Physical Science and TechnologyNanjing Normal UniversityNanjingJiangsu210023 China

The reaction of DyCl_(3)·6H_(2)O with a rigid diacylhydrazone ligand(H_(2)L)afforded a trinuclear precursor[Dy_(3)L_(2)Cl_(3)(H_(2)O)_(2)(CH_(3)OH)]Cl_(2)·3CH_(3)OH(1).The replacement of the Cl-ions and the coordinating solvents by the aryloxides ligands(Lx)-yields three trinuclear complexes[Dy_(3)L_(2)(Lx)_(5)]·nsol(x=1,2-naphthol(2);x=2,7-hydroxycoumarin(3);and x=3,phenol(4)).In complexes 2-4,two end Dy^(3+)centers adopt almost identical N_(4)O_(4) coordination sphere of D6h geometry while the central one adopts N_(4)O_(5) coordination sphere in Cs *** measurements reveal weak antiferromagnetic interactions in the hydrated samples 2e-4e and two-step slow relaxation process under zero dc field with effective energy barriers Ueff of 439 and 91 K,353 and 40 K,466 and 89 K for SR and FR in 2e-4e,*** dynamic magnetic behaviour for 4 persists in the magnetically diluted sample of 4@*** 4 possesses the short Dy-O_(aryloxide) bond distance of 2.055(18)Å,and the largest Ueff among the reported linear trinuclear dysprosium ***,the functionalized aryloxides ligands(Lx)-show photoluminescence via intramolecular energy transfer,making 2e-4e luminescent Dy^(3+)SMMs with high energy barriers.

关键词： Coordination modes Lanthanides Crystal structure Ab initio calculations Magnetic properties Luminescence

Pressure-induced bimetallic carbon nanotubes from metalorganic frameworks as optimized bifunctional electrocatalysts for water splitting

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Rare Metals 2023年第1期42卷 155-164页

作者： Hong-Xu Chen hui Xu Zhi-Rong Song yi liu hui Cui Jun-Kuo Gao Key Laboratory of Rare Earth Optoelectronic Materials and Devices of Zhejiang Province Institute of Optoelectronic Materials and DevicesCollage of Optical and Electronic TechnologyChina Jiliang UniversityHangzhou310018China Institute of Functional Porous Materials School of Materials Science and EngineeringZhejiang Sci-Tech UniversityHangzhou310018China Institute for Composites Science Innovation School of Materials Science and EngineeringZhejiang UniversityHangzhou310027China Argonne National Laboratory Physics DivisionLemontIL60439USA Department of Chemistry and International Institute for Nanotechnology(IIN) Northwestern UniversityEvanstonIL60208USA

Carbon nanotubes(CNTs)have attracted great interest in numerous applications due to their excellent electronic and structural ***,harsh synthesis conditions and high energy consumption limit the further application of ***,we developed a facile and innovative strategy to generate CNTs by physically pressurizing metal-organic frameworks(MOFs)and then *** synthesized bimetallic nitrogen/sulfur double-doped carbon nanotubes are denoted as Fe_(x)Co_(1-x)P(x=0.5,0.6,0.7,0.8,0.9).The introduction of pressure not only revolutionized the morphology of the electrocatalysts,but also enhanced the activity of oxygen evolution reaction(OER)and hydrogen evolution reaction(HER)in alkaline ***_(0.6)Co_(0.4)-P exhibits superior OER and HER performances in 1.0 mol·L^(-1)KOH solution with overpotentials of 364 and 346 mV at 10 mA·cm^(-2),which are 28 and 5 mV lower than unpressurized Fe0.6Co0.4.

关键词： Metal-organic frameworks(MOFs) Carbon nanotubes(CNTs) Bifunctional Pressurizing Oxygen evolution reaction(OER) Hydrogen evolution reaction(HER)