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定向电场下W_(6)C_(6)团簇的超卤素调制及非线性光学特性

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原子与分子物理学报 2025年第3期42卷 72-76页

作者：蔡璧钧段宇静魏强重庆理工大学理学院重庆400050

本文采用密度泛函(DFT)方法研究了定向外电场(OEEF)对W_(6)C_(6)团簇几何结构、电子性质以及非线性光学响应(NLO)的影响.计算结果表明W_(6)C_(6)的结构在一定OEEF强度下可以保持稳定.OEEF可以增大W_(6)C_(6)团簇的电子亲和能(EA值),且... 详细信息

本文采用密度泛函(DFT)方法研究了定向外电场(OEEF)对W_(6)C_(6)团簇几何结构、电子性质以及非线性光学响应(NLO)的影响.计算结果表明W_(6)C_(6)的结构在一定OEEF强度下可以保持稳定.OEEF可以增大W_(6)C_(6)团簇的电子亲和能(EA值),且在特定强度下,OEEF可以将W_(6)C_(6)团簇转变为超卤素.通过对EA值的非线性拟合可以实现对W_(6)C_(6)团簇的连续调制.进一步对不同外电场下W_(6)C_(6)团簇的最高占据分子轨道(HOMO)和最低未占据分子轨道(LUMO)能级进行分析,发现OEEF降低了W_(6)C_(6)团簇LUMO能级是其EA值增大的主因.此外,OEEF可以显著增大W_(6)C_(6)团簇的平均极化率和第一超极化率,尤其是第一超极化率,改变其非线性光学性质.

关键词：定向外电场超原子密度泛函理论 NLO W_(6)C_(6)团簇

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Granger causal representation learning for groups of time series

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Science China(Information Sciences) 2024年第5期67卷 56-68页

作者： Ruichu cai Yunjin WU Xiaokai HUANG Wei CHEN Tom Z.j.FU Zhifeng HAO School of Computer Science Guangdong University of Technology Peng Cheng Laboratory College of Science Shantou University

Discovering causality from multivariate time series is an important but challenging *** existing methods focus on estimating the Granger causal structures among multivariate time series,while ignoring the prior knowledge of these time series, e.g., the group of the time series. Focusing on discovering the Granger causal structures among groups of time series, we propose a Granger causal representation learning method to solve this problem. First, we use the multiset canonical correlation analysis method to learn the Granger causal representation of each group of time series. Then, we model the Granger causal relationships among the learned Granger causal representations using a recurrent neural network with temporal information. Finally, we formulate the above two stages into one unified optimization problem, which is efficiently solved using the augmented Lagrangian method. We conduct extensive experiments on synthetic and real-world datasets to validate the correctness and effectiveness of the proposed method.

关键词： Granger causal discovery Granger causal representation learning time series data recurrent neural network multiset canonical correlation analysis

Dynamics of a Stochastic Epidemic Model with Age-group

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应用数学 2025年第1期38卷 294-307页

作者： LAN Xiaomin CHEN Guangmin ZHOU Ruiyang ZHENG Kuicheng cai Shaojian WEI Fengying jIN Zhen MAO Xuerong School of Mathematics and Statistics Fuzhou UniversityFuzhou 350116China Fujian Provincial Center for Disease Control and Prevention Fuzhou 350012China Center for Applied Mathematics of Fujian Province Fuzhou UniversityFuzhou 350116China Key Laboratory of Operations Research and Control of Universities in Fujian Fuzhou UniversityFuzhou 350116China Complex models Research Center Shanxi UniversityTaiyuan 030006China Department of Mathematics and Statistics University of StrathclydeGlasgowG11XHUK

A stochastic epidemic model with two age groups is established in this study,in which the susceptible(S),the exposed(E),the infected(I),the hospitalized(H)and the recovered(R)are involved within the total population,the aging rates between two age groups are set to be *** existence-and-uniqueness of global positive solution is firstly ***,by constructing several appropriate Lyapunov functions and using the high-dimensional Itô’s formula,the sufficient conditions for the stochastic extinction and stochastic persistence of the exposed individuals and the infected individuals are *** stochastic extinction indicator and the stochastic persistence indicator are less-valued expressions compared with the basic reproduction ***,the main results of this study are modified into multi-age ***,by using the surveillance data for Fujian Provincial Center for Disease Control and Prevention,Fuzhou COVID-19 epidemic is chosen to carry out the numerical simulations,which show that the age group of the population plays the vital role when studying infectious diseases.

关键词： Epidemic model Age groups Persistence Extinction

区域一体化与企业数字化转型——基于市场竞争和创新驱动的视角

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云南财经大学学报 2025年第1期41卷 51-68页

作者：李志聪蔡欣荣陆帆中南财经政法大学财政税务学院武汉430073 中央财经大学财政税务学院北京102206

通过以长三角区域一体化试点政策为准自然实验,利用2008—2021年沪深A股上市企业的数据,考察了区域一体化政策对企业数字化转型的影响和内在机理。研究发现,区域一体化政策能够显著提升企业数字化水平,该结论在稳健性检验后仍然成立。... 详细信息

通过以长三角区域一体化试点政策为准自然实验,利用2008—2021年沪深A股上市企业的数据,考察了区域一体化政策对企业数字化转型的影响和内在机理。研究发现,区域一体化政策能够显著提升企业数字化水平,该结论在稳健性检验后仍然成立。从不同维度来看,区域一体化政策显著促进了数字技术发展的深度(底层数字技术应用)和融合发展的广度(智能制造和互联网商业模式)。机制检验表明,区域一体化政策改善了宏观层面的市场竞争环境和创新环境,从而增强了企业面临的赶超压力和驱动企业进行创新策略调整,进而提升企业数字化水平。异质性分析表明,区域一体化政策的数字化发展效应主要存在于国有企业、成长型企业、数字金融发展水平高和知识产权保护重视程度高的地区。进一步研究显示,区域一体化政策不仅促进了企业专业化分工,同时改善了企业资源错配。研究结论不仅为化解企业数字化转型困境提供了经验证据,也为政府深入推进区域一体化协调发展和构建统一大市场提供参考。

关键词：区域一体化企业数字化转型市场竞争创新驱动

An improved CRISPRi system in Pichia pastoris

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Synthetic and Systems Biotechnology 2023年第3期8卷 479-485页

作者： Shujing Qiao Fan Bai Peng cai Yongjin j.Zhou Lun Yao Division of Biotechnology Dalian Institute of Chemical PhysicsChinese Academy of Sciences457 Zhongshan RoadDalian116023PR China CAS Key Laboratory of Separation Science for Analytical Chemistry Dalian Institute of Chemical PhysicsChinese Academy of SciencesDalian116023PR China Dalian Key Laboratory of Energy Biotechnology Dalian Institute of Chemical PhysicsCAS457 Zhongshan RoadDalian116023PR China University of Chinese Academy of Sciences Beijing100049China

CRISPR interference(CRISPRi)has been developed and widely used for gene repression in various *** we report an improved CRISPRi system in Pichia pastoris by fusing dCas9 with endogenous transcriptional repressor *** CRISPRi system shows strong repression of eGFP,with the highest efficiency of 85%.Repression of native genes is demonstrated by targeting AOX1 ***1 is efficiently repressed and the mutant strains show much slower growth in methanol *** of gRNA expression and processing on CRISPRi efficiency is also *** is found that gRNA processing by HH/HDV ribozymes or Csy4 endoribonuclease generating clean gRNA is critical to achieve strong repression,and Csy4 cleavage shows higher repression ***,gRNA expression using native tRNA transcription and processing systems results in relatively weaker repression of *** expression of two gRNAs targeting promoters of eGFP and AOX1 in an array together with Cys4 recognition sites,both genes can be repressed ***4-mediated gRNA array processing is further applied to repress fatty acyl-CoA synthetase genes(FAA1 and FAA2).Both genes are efficiently repressed,demonstrating that Cys4 endoribonuclease has the ability to cleave gRNAs array and can be can be used for multiplexed gene repression in ***.

关键词： Pichia pastoris CRISPRi HH/HDV Csy4 gRNA array

Expression of E-cadherin and β-catenin in gastric carcinoma and its correlation with the clinicopathological features and patient survival

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World journal of Gastroenterology 2002年第6期8卷 987-993页

作者： Yong-NingZhou cai-PuXu BiaoHan MinLi LiangQiao Dian-chunFang j DepartmentofGastrocntcrology SouthwastHospitaltheThirdMillitaryMedicalUniversityChongqing400038 DepartmentofParhology LanzhouMedicalCollgegLanzhouGansuProvince730000 FirstTeachingHospital Lanzhou

AIM:The E-cadherin-catedin complex is important for cell-cell adhesion of epithelial *** of one or more components of this comples is associated with poor differentiation and increased invasiveness of carcinomas,We evaluated the expression pattern of E-cadherin and β-catenin in gastric carcinoma and dysplasia and analyzed their relationship with tumor clinicopathological featrres and patient survival.

关键词：胃癌患者存活率 E-钙粘着蛋白 β-联蛋白基因表达临床病理特征相关性

Protection of Large-scale Wind Power Integration

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电力系统自动化 2012年第8期36卷 132-135页

作者： cai, Rong Su, Bin ABB China Corporate Research Center Beijing 100015 China

More and more large capacity wind power will be integrated into power system in the future,and certain technical challenges will emerge due to the fluctuation characteristics of wind power and the complex control of power electronic devices inside the wind turbines(e.g.,low voltage ride through(LVRT)).By comparing a wind power integration grid with a hydropower integration grid,the special transient phenomena caused by the wind power integration is studied and simulation results are ***,the potential impacts on the traditional protection are *** show that the special transient phenomena can decrease the sensitivity,reliability and operation speed of conventional protections.

关键词：风力发电常规保护一体化电力电子器件风力涡轮机电力系统波动特性仿真结果

Mass transfer in gas–liquid stirred reactor with various triple-impeller combinations

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Chinese journal of Chemical Engineering 2016年第6期24卷 703-710页

作者： jinjin Zhang Zhengming Gao Yating cai Ziqi cai jie Yang Yuyun Bao State Key Laboratory of Chemical Resource Engineering School of Chemical Engineering Beijing University of Chemical Technology Beijing 100029 China School of Chemical Engineering Shandong University of Technology Zibo 255000 China

The gassed power demand and volumetric mass transfer coefficient （kca） were investigated in a fully baffled, dished-base stirred vessel with a diameter of 0.30 m agitated by five triple-impeller combinations. Six types of impellers （six-half-elliptical-blade disk turbine （HEDT）, four-wide-blade hydrofoil impeller （WH） pumping down （D） and pumping up （U）, parabolic-blade disk turbine （PDT）, and CBY narrow blade （N） and wide blade （W）） were used to form five combinations identified by PDT ＋ 2CBYN, PDT ＋ 2CBYw, PDT ＋ 2WHD, HEDT ＋ 2WHD and HEDT ＋ 2WHo, respectively. The results show that the relative power demand of HEDT ＋ 2WHu is higher than that of other four impeller combinations under all operating conditions. At low superficial gas velocity （uc）, kLa differences among impeller combinations are not obvious. However when UG iS high, PDT ＋ 2WHD shows the best mass transfer performance and HEDT ＋ 2WHu shows the worst mass trans- fer performance under all operating conditions. At high uc and a given power input, the impeller combinations with high agitation speed and big projection cross-sectional area lead to relatively high values of kLa. Based on the experimental data, the regressed correlations of gassed power number with Froude number and gas flow number, and kLa with power consumption and superficial gas velocity are obtained for five different impeller combinations, which could be used as guidance for industrial design.

关键词： Stirred vesselGassed powerMass transferTriple-impeller combinationGas-liquid system

Estimation of the j-resistance curve for Cr2Ni2MoV steel using the modified load separation parameter S_(pb) method

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journal of Zhejiang University-Science A(Applied Physics & Engineering) 2010年第10期11卷 782-788页

作者： Chen BAO Li-xun cai School of Mechanics and Engineering Southwest Jiaotong University Chengdu 610031 China

Based on load separation theory, the load separation parameter Spb method is an effective approach for estimating the j-resistance curve from records of load versus displacement directly, using one sharp cracked specimen and an additional reference blunt cracked specimen. However, the effect of the reference blunt cracked specimen on j-resistance determination was not explicitly considered in past work. In this paper, a modified load separation parameter Spb method was developed to eliminate this effect, and then a unique estimation of instantaneous crack length for one sharp cracked specimen could be obtained. Furthermore, a forced blunting calibration method was also adopted to determine the instantaneous crack length in the load inseparable region, referring to a normalization method. Experiments on steam turbine rotator steel Cr2Ni2MoV were carried out to estimate j-resistance curves using an unloading compliance method. By removing unload and reload data from load-displacement records, the j-resistance curve for the same sharp cracked specimen was estimated using the modified separation parameter Spb method. The results indicate that the modified Spb method completely eliminates the effect of the reference blunt cracked specimen on the instantaneous crack length determination of the sharp cracked specimen. However, different j-resistance curves in a small range of crack extension are present when different blunting coefficients are used in the blunting line equation. The j-resistance curve obtained from the modified Spb method agrees well with that obtained from the compliance method.

关键词： Load separation j-resistance curve Separation parameter Spb Blunt cracked specimen Forced blunting calibration