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Acta Mathematicae Applicatae Sinica 2018年第3期34卷 553-565页

作者： Shi-jie WANG Chuan-wei ZHANG Xue-jun WANG wen-sheng WANG School of Mathematic Sciences Anhui University Hefei 230601 China School of Economics Hangzhou Dianzi University Hangzhou 310018 China

Consider a discrete-time risk model with insurance and financial risks in a stochastic economic environment. Assume that the insurance and financial risks form a sequence of independent and identically distributed random vectors with a generic random vector following a wide type of dependence structure. An asymptotic formula for the finite-time ruin probability with subexponential insurance risks is derived. In doing so, the subexponentiality of the product of two dependent random variables is investigated simultaneously.

关键词： discrete-time risk model finite-time ruin probability subexponentiality product dependence structure

Shadow obstacle model for realistic corner-turning behavior in crowd simulation

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Frontiers of Information Technology & Electronic Engineering 2016年第3期17卷 200-211页

作者： Gao-qi HE yi JIN Qi CHEN Zhen LIU wen-hui YUE Xing-jian LU Department of Computer Science and Engineering East China University of Science and Technology Shanghai 200237 China MOE Key Laboratory of Geographic Information Science East China Normal University Shanghai 200241 China State Key Laboratory of Virtual Reality Technology and Systems Beihang University Beijing 100191 China College of Information Science and Technology Ningbo University Ningbo 315211 China

This paper describes a novel model known as the shadow obstacle model to generate a realistic comer-tuming behavior in crowd simulation. The motivation for this model comes from the observation that people tend to choose a safer route rather than a shorter one when turning a comer. To calculate a safer route, an optimization method is proposed to generate the corner-turning rule that maximizes the viewing range for the agents. By combining psychological and physical forces together, a full crowd simulation framework is established to provide a more realistic crowd simulation. We demonstrate that our model produces a more realistic comer-turning behavior by comparison with real data obtained from the experiments. Finally, we per- form parameter analysis to show the believability of our model through a series of experiments.

关键词： Comer-turning behavior Crowd simulation Safety awareness Rule-based model

Roasting and leaching behaviors of vanadium and chromium in calcification roasting–acid leaching of high-chromium vanadium slag

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International Journal of Minerals,Metallurgy and Materials 2018年第5期25卷 515-526页

作者： Jing wen Tao Jiang Mi Zhou Hui-yang Gao Jia-yi Liu Xiang-xin Xue School of Metallurgy Northeastern University Liaoning Key Laboratory for Recycling Science of Metallurgical Resources

Calcification roasting–acid leaching of high-chromium vanadium slag(HCVS)was conducted to elucidate the roasting and leaching behaviors of vanadium and *** effects of the purity of Ca O,molar ratio between Ca O and V_2O_5(n(Ca O)/n(V_2O_5)),roasting temperature,holding time,and the heating rate used in the oxidation–calcification processes were *** roasting process and mechanism were analyzed by X-ray diffraction(XRD),scanning electron microscopy(SEM),and thermogravimetry–differential scanning calorimetry(TG–DSC).The results show that most of vanadium reacted with Ca O to generate calcium vanadates and transferred into the leaching liquid,whereas almost all of the chromium remained in the leaching residue in the form of(Fe_(0.6)Cr_(0.4))_2O_*** trends of the vanadium and chromium leaching ratios were always opposite because of the competitive reactions of oxidation and calcification between vanadium and chromium with Ca ***,Ca O was more likely to combine with vanadium,as further confirmed by thermodynamic *** the HCVS with Ca O added in an n(Ca O)/n(V_2O_5)ratio of 0.5 was roasted in an air atmosphere at a heating rate of 10°C/min from room temperature to 950°C and maintained at this temperature for 60 min,the leaching ratios of vanadium and chromium reached91.14%and 0.49%,respectively;thus,efficient extraction of vanadium from HCVS was achieved and the leaching residue could be used as a new raw material for the extraction of ***,the oxidation and calcification reactions of the spinel phases occurred at 592and 630°C for n(Ca O)/n(V_2O_5)ratios of 0.5 and 5,respectively.

关键词： high-chromium vanadium slag calcification roasting roasting behaviors leaching behaviors vanadium extraction

急性氨氮胁迫下大口黑鲈的肝脏转录组特征分析

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水生生物学报 2024年第5期48卷 713-724页

作者：刘品王文博李超严少普李琪罗小敏张硕华张艺琛姚林荣咸阳师范学院生命科学系咸阳712000 西安市水产工作站西安710000

为研究大口黑鲈(Micropterus salmoides)受到氨氮胁迫时基因表达的变化规律,文章采用Illumina平台的HiSeq测序策略分析了氨氮胁迫12h和24h后大口黑鲈肝脏的基因表达谱。氨氮胁迫后在大口黑鲈肝脏共获得111.66 Gb的有效数据,组装获得133... 详细信息

为研究大口黑鲈(Micropterus salmoides)受到氨氮胁迫时基因表达的变化规律,文章采用Illumina平台的HiSeq测序策略分析了氨氮胁迫12h和24h后大口黑鲈肝脏的基因表达谱。氨氮胁迫后在大口黑鲈肝脏共获得111.66 Gb的有效数据,组装获得133486个单基因簇(Unigenes),N50为1000 bp。通过比较转录组分析在2个时间点共获得2072个差异表达基因,其中氨氮胁迫12h获得1516个差异表达基因,907个上调,609个下调;氨氮胁迫24h获得556个差异表达基因,其中330个上调,226个下调。GO功能注释分析结果表明,在氨氮胁迫12h差异基因富集数目明显多于24h,但在“氧化还原酶活性”条目中富集的差异基因数目则是氨氮胁迫24h多于12h。此外,KEGG功能富集分析发现,氨氮胁迫对大口黑鲈肝脏氧化应激、细胞自噬和凋亡相关等途径产生影响。选取10个差异表达基因进行qPCR验证,其表达水平与转录组差异基因分析结果一致,证明了测序结果的可靠性。其中,与氧化应激相关基因缺氧诱导因子1α(HIF1α)、生长停滞DNA损伤可诱导蛋白β(Gadd45β)、DNA损伤诱导转录因子4(DDIT4)、与细胞自噬相关基因自噬微管相关蛋白轻链3(LC3)及与细胞凋亡相关基因下游内质网氧化还原酶1α(Ero1α)在整个胁迫过程中均显著上调。综上所述,氨氮胁迫能引起大口黑鲈肝脏氧化应激,当机体调控作用不足时,大口黑鲈通过细胞自噬与凋亡方式去除受损细胞,以维持内环境稳定。研究结果将为进一步研究大口黑鲈在氨氮胁迫下生理调控的分子机制提供依据。

关键词：氨氮胁迫转录组肝脏大口黑鲈

Coordination Structure of Aluminum in Magnesium Aluminum Hydroxide Studied by (27)Al NMR

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Chinese Chemical Letters 2003年第6期14卷 605-608页

作者： Shu Hua HAN Wan Guo HOU wen Xiu DANG jun XU Key Lab of Colloid and Interface Chemistry of State Education Ministry Shandong UniversityJinan 250100

The coordination structure of aluminum in magnesium aluminum hydroxide was studied by 27Al NMR. The result showed that tetrahedral aluminum (AlIV) existed in magnesium aluminum hydroxide, and the contents of AlIV increased with the increase of the ratio of Al/Mg and with the peptizing temperature. AlIV originated from the so-called Al13 polymer with the structure of one Al tetrahedron surrounded by twelve Al octahedrons.

关键词： Coordination structure magnesium aluminum hydroxide 27Al NMR.

C–H allylation of N-aryl-tetrahydroisoquinolines by merging photoredox catalysis with iodide catalysis

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Science China Chemistry 2016年第2期59卷 171-174页

作者： Zhujia Feng Tingting Zeng jun Xuan Yunhang Liu Liangqiu Lu wen-Jing Xiao CCNU-u Ottawa Joint Research Center College of Chemistry Central China Normal University

A dual catalytic system, combing visible light photoredox catalysis and iodide catalysis, has been developed for the functionalization of inert C–H bonds. By doing so, radical allylation reactions of N-aryl-tetrahydroisoquinolines(THIQs) were realized under extremely mild conditions, affording a wide variety of allyl-substituted THIQs in up to 78% yields.

关键词： visible light photocatalysis iodide catalysis allylation tetrahydroisoquinolines

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轨道阱边缘场效应及其补偿方法的研究

质谱学报 2024年第2期45卷 237-245页

作者：王俊恬任熠黄正旭陈政阁丁力暨南大学质谱仪器与大气环境研究所广东广州510632 广东省麦思科学仪器创新研究院广东广州510530 广州禾信仪器股份有限公司广东广州510530 宁波大学材料科学与化学工程学院浙江宁波315211

静电轨道阱(Orbitrap)自推出以来已被证明是一款强大的离子分析器,其分辨率受电极结构中边缘场的影响。因此,亟需研究由离子入射孔和外电极间隙共同导致的畸变场对分辨率的影响,并提出边缘场效应的解决方法。本实验利用离子光学仿真软件... 详细信息

静电轨道阱(Orbitrap)自推出以来已被证明是一款强大的离子分析器,其分辨率受电极结构中边缘场的影响。因此,亟需研究由离子入射孔和外电极间隙共同导致的畸变场对分辨率的影响,并提出边缘场效应的解决方法。本实验利用离子光学仿真软件(SIMION)分别建立了理想、畸变和矫正3种结构模型,以测量不同初始轴向振幅和不同轨道半径对应的轴向振动周期分散来衡量轨道阱可以达到的极限分辨率。通过对比理想模型的实验结果与理论结果,验证了仿真参数选取和离子运动计算方法的可靠性;在畸变模型实验中,探究外电极间隙和离子入射孔导致的边缘场效应引起的离子轴向运动周期分散情况,及其对分辨率产生的影响;在矫正模型实验中证明了可以通过调节2个补偿电极的电压来修正畸变场,从而克服离子入射孔和外电极间隙共同产生的边缘场效应,乃至其他缺陷所引起的场畸变问题,仿真得到轨道阱对m/z 100离子的极限质量分辨率可达2500000。

关键词：轨道阱边缘场补偿电极分辨率仿真模拟

Yb modified NaY zeolite: A recyclable and efficient catalyst for quinoxaline synthesis

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Chinese Chemical Letters 2014年第8期25卷 1203-1206页

作者： Li-Yan Fan Lin Wei wen-jun Hua Xiang-Xiong Li Department of Chemistry Tongji University

In this study, Yb immobilized NaY zeolite catalyst（Yb/NaY） was obtained by a hydrothermal method and characterized by XRD, BET, FT-IR, ICP-AES, and NH3-TPD. The catalyst displayed good catalytic activity when applied to the synthesis of quinoxalines via condensation of a-hydroxyketones with 1,2-diamines,and could be reused several times without any loss of catalytic activity.

关键词： Yb/NaY Recyclable Quinoxaline α-Hydroxyketone

Research on Positioning Error Compensation for Micro Milling Machine Tool

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Journal of Harbin Institute of Technology(New Series) 2014年第5期21卷 101-106页

作者： Ming-jun Chen wen-Lan Tian Yong Xiao Yan Jiang Center for Precision Engineering Harbin Institute of Technology

Micro milling has many advantages in fabricating three-dimensional(3D) structure in micrometer scale. The micro milling machine tool with high positioning accuracy is of great importance for getting micro structure with high profile precision and good surface quality. Meanwhile, the method of position error compensation is a good way to improve the accuracy of the micro milling machine tools. In this paper,a software method is adopted to compensate the positioning error and improve the positioning accuracy. According to error cancellation theory,the compensation values are generated and compensation tables are built to adjust the positioning error in the NC system based on Industrial Motion and Automation Control( IMAC). The positioning accuracy of linear motor is ± 0. 3 μm without backlash after compensation. In order to verify the effectiveness of compensation on the machining performance,concave spherical surfaces are processed on the micro milling machine tool. The experimental results show that the profile radius error of the spherical surface machined with compensation decreases more than 60%.

关键词： positioning error compensation micro milling IMAC spherical surface

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)