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类杯芳烃孔穴桥联双芘分子开关化合物

高等学校化学学报 2015年第12期36卷 2421-2426页

作者：徐海赵斯祺任扬蔡健峰汪翔林雨霖中南大学化学化工学院长沙410083

利用构型可变的分子开关类杯芳烃孔穴化合物(Cavitand)作为母体,合成了2种具有不同臂长的双芘Cavitand化合物.在室温及中性状态下,2种双芘Cavitand化合物均可检验出分子内激基复合物荧光,其中短臂双芘Cavitand化合物的荧光明显强于长臂C... 详细信息

利用构型可变的分子开关类杯芳烃孔穴化合物(Cavitand)作为母体,合成了2种具有不同臂长的双芘Cavitand化合物.在室温及中性状态下,2种双芘Cavitand化合物均可检验出分子内激基复合物荧光,其中短臂双芘Cavitand化合物的荧光明显强于长臂Cavitand化合物.经三氟乙酸酸化后,2种双芘化合物的分子内激基复合物荧光消失;而继续使用碱中和至中性,则荧光恢复.这个荧光出现-消失-出现的过程验证了Cavitand母体化合物分子构型闭合-打开-闭合可有效调控分子激基复合物荧光开关过程.此外,通过高斯计算模拟了2种化合物的理论分子构型,发现长臂双芘化合物在Cavitand母体构型处于闭合状态时2个芘基团重叠部分较少是其分子内激基复合物荧光较弱的关键原因.

关键词：分子开关类杯芳烃孔穴化合物荧光双芘Cavitand化合物

Effects of zeolite imidazole frameworks on rice seedlings (Oryza sativa L.): Phytotoxicity, transformation, and bioaccumulation

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Journal of Environmental Sciences 2024年第10期144卷 15-25页

作者： Chaofa Chen Yongqi Yao Chenghua Xing Yunyu Guo Luyi cai Jianfang Yan Xi-Lin Wu Miaozhen cai College of Geography and Environmental Science Zhejiang Normal UniversityJinhuaZhejiang 321004China College of Agriculture Jinhua PolytechnicJinhuaZhejiang 321007China

Zeolite imidazole frameworks(ZIFs),a class of the metal organic framework,have been extensively studied in environmental ***,their environmental fate and potential ecological impact on plants remain ***,we investigated the phytotoxicity,transformation,and bioaccumulation processes of two typical ZIFs(ZIF-8 and ZIF-67)in rice(Oryza sativa L.)under hydroponic ***-8 and ZIF-67 in the concentration of 50 mg/L decreased root and shoot dry weight maximally by 55.2%and 27.5%,53.5%and 37.5%,*** scanning electron microscopy(SEM)imaging combined with X-ray diffraction(XRD)patterns revealed that ZIFs on the root surface gradually collapsed and transformed into nanosheets with increasing cultivation *** fluorescein isothiocyanate(FITC)labeled ZIFs were applied to trace the uptake and translocation of ZIFs in *** results demonstrated that the transformed ZIFs were mainly distributed in the intercellular spaces of rice root,while they cannot be transported to culms and *** so,the Co and Zn contents of rice roots and shoots in the ZIFs treated groups were increased by 1145%and 1259%,145%and 259%,respectively,compared with the control *** findings suggested that the phytotoxicity of ZIFs are primarily attributed to the transformed ZIFs and to a less extent,the metal ions and their ligands,and they were internalized by rice root and increased the Co and Zn contents of *** study reported the transformation of ZIFs and their biological effectiveness in rice,highlighting the potential environmental hazards and risks of ZIFs to crop plants.

关键词： Zeolitic imidazolate frameworks (ZIFs) Rice(Oryza sativa L.) Phytotoxicity Transformed ZIFs ZIFs bioaccumulation

WEAK APPROXIMATIONS OF STOCHASTIC PARTIAL DIFFERENTIAL EQUATIONS WITH FRACTIONAL NOISE

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Journal of Computational Mathematics 2024年第3期42卷 735-754页

作者： Meng cai Siqing Gan Xiaojie Wang School of Mathematics and Statistics HNP-LAMACentral South UniversityChangshaChina

This paper aims to analyze the weak approximation error of a fully discrete scheme for a class of semi-linear parabolic stochastic partial differential equations(SPDEs)driven by additive fractional Brownian motions with the Hurst parameter H∈(1/2,1).The spatial approximation is performed by a spectral Galerkin method and the temporal discretization by an exponential Euler *** far as we know,the weak error analysis for approximations of fractional noise driven SPDEs is absent in the literature.A key difficulty in the analysis is caused by the lack of the associated Kolmogorov *** the present work,a novel and efficient approach is presented to carry out the weak error analysis for the approximations,which does not rely on the associated Kolmogorov equations but relies on the Malliavin *** the best of our knowledge,the rates of weak convergence,shown to be higher than the strong convergence rates,are revealed in the fractional noise driven SPDE setting for the first *** examples corroborate the claimed weak orders of convergence.

关键词： Parabolic SPDEs Fractional Brownian motion Weak convergence rates Spec-tral Galerkin method Exponential Euler method Malliavin calculus

A COUPLED METHOD COMBINING CROUZEIX-RAVIART NONCONFORMING AND NODE CONFORMING FINITE ELEMENT SPACES FOR BOIT CONSOLIDATION MODEL

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Journal of Computational Mathematics 2024年第4期42卷 911-931页

作者： Yuping Zeng Mingchao cai Liuqiang Zhong School of Mathematics Jiaying UniversityMeizhou 514015China Department of Mathematics Morgan State University1700 E Cold Spring LnBaltimoreMD 21251USA School of Mathematical Science South China Normal UniversityGuangzhou 520631China

A mixed finite element method is presented for the Biot consolidation problem in *** precisely,the displacement is approximated by using the Crouzeix-Raviart nonconforming finite elements,while the fuid pressure is approximated by using the node conforming finite *** well-posedness of the fully discrete scheme is established,and a corresponding priori error estimate with optimal order in the energy norm is also *** experiments are provided to validate the theoretical results.

关键词： Poroelasticity Nonconforming finite element Inf-sup condition A priori error estimate

Automatic Requirement Dependency Extraction Based on Integrated Active Learning Strategies

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Machine Intelligence Research 2024年第5期21卷 993-1010页

作者： Hui Guan Guorong cai Hang Xu Department of Computer Science and Technology Shenyang University of Chemical TechnologyShenyang110142China Key Laboratory of Industrial Intelligence Technology on Chemical Process Shenyang110142China

Since requirement dependency extraction is a cognitively challenging and error-prone task,this paper proposes an automatic requirement dependency extraction method based on integrated active learning *** this paper,the coefficient of variation method was used to determine the corresponding weight of the impact factors from three different angles:uncertainty probability,text similarity difference degree and active learning variant prediction divergence *** combining the three factors with the proposed calculation formula to measure the information value of dependency pairs,the top K dependency pairs with the highest comprehensive evaluation value are selected as the optimal *** the optimal samples are continuously added into the initial training set,the performance of the active learning model using different dependency features for requirement dependency extraction is rapidly ***,compared with other active learning strategies,a higher evaluation measure of requirement dependency extraction can be achieved by using the same number of ***,the proposed method using the PV-DM dependency feature improves the weight-F1 by 2.71%,the weight-recall by 2.45%,and the weight-precision by 2.64%in comparison with other strategies,saving approximately 46%of the labelled data compared with the machine learning approach.

关键词： Requirement dependency dependency extraction dependency features integrated active learning strategies coefficient of variation

Doped holographic superconductors in the Gubser–Rocha model

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Communications in Theoretical Physics 2024年第4期76卷 80-92页

作者： Ziyi Zhao Wenhe cai Shuta Ishigaki Department of Physics Shanghai UniversityShanghai 200444China Shanghai Key Laboratory of High Temperature Superconductors Department of PhysicsShanghai UniversityShanghai 200444China

We construct a doped holographic superconductor in the Gubser–Rocha model,and realize a superconducting dome in the middle of the temperature-doping phase *** is worth noting that unlike in previous research,the profile of our dome shrinks inward near to zero *** the numerical observation for the coupling dependence of the phase diagram,we find that the coupling between the two gauge fields plays a crucial role in the formation of the *** also analytically calculate the DC conductivity of the normal phase of the system in the momentum dissipation and obtain resistivity which is proportional to the *** AC conductivity is calculated numerically.

关键词： AdS-CFT correspondence High-Tc superconductor AC/DC conductivities Gubser-Rocha geometry

BSEC Method for Unveiling Open Clusters and its Application to Gaia DR3:83 New Clusters

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Research in Astronomy and Astrophysics 2024年第5期24卷 169-184页

作者： Zhong-Mu Li cai-Yan Mao Institute of Astronomy and Information Dali UniversityDali 671003China

Open clusters(OCs) are common in the Milky Way, but most of them remain undiscovered. There are numerous techniques, including some machine-learning algorithms, available for the exploration of OCs. However, each method has its limitations and therefore, different approaches to discovering OCs hold significant values. We develop a comprehensive approach method to automatically explore the data space and identify potential OC candidates with relatively reliable membership determination. This approach combines the techniques of Hierarchical Density-Based Spatial Clustering of Applications with Noise, Gaussian mixture model, and a novel cluster member identification technique, color excess constraint. The new method exhibits efficiency in detecting OCs while ensuring precise determination of cluster memberships. Because the main feature of this technique is to add an extra constraint(EC) for the members of cluster candidates using the homogeneity of color excess,compared to typical blind search codes, it is called Blind Search-Extra Constraint(BSEC) method. It is successfully applied to the Gaia Data Release 3, and 83 new OCs are found, whose color–magnitude diagrams(CMDs) are fitted well to the isochrones. In addition, this study reports 621 new OC candidates with discernible main sequence or red giant branch. It is shown that BSEC technique can discard some false negatives of previous works, which takes about three percentage of known clusters. It shows that as an EC, the color excess(or twocolor) constraint is useful for removing fake cluster member stars from the clusters that are identified from the positions and proper motions of stars, and getting more precise CMDs, when differential reddening of member stars of a cluster is not large(e.g., ΔE(G_(BP)-G_(RP)) < 0.5 mag). It makes the CMDs of 15% clusters clearer(in particular for the region near turnoff) and therefore is helpful for CMD and stellar population studies. Our result suggests that the color excess con

关键词： Galaxy stellar content-(Galaxy:)open clusters and associations general-stars fundamental parameters

Spin-based magnetic random-access memory for high-performance computing

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National Science Review 2024年第3期11卷 20-23页

作者： Kaiming cai Tianli Jin Wen Siang Lew School of Physics Huazhong University of Science and Technology Interuniversity Microelectronics Centre(IMEC) School of Physical and Mathematical Sciences Nanyang Technological University

Memory serves as a critical component in today's electronic systems for data storage and processing. In traditional computer architectures, the logic and memory units are physically separated, due to the performance gap in operational speed and capacity among memories, resulting in the fundamental limitation of the von Neumann computers.

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科技中介服务机构核心员工薪酬体系的设计

科技进步与对策 2005年第6期22卷 164-166页

作者：郎丽慧蔡建峰郭鹏西北工业大学管理学院陕西西安710072

科技中介服务机构在向专业化、市场化和企业化转化的过程中,为激励、吸引和留住核心员工,必须建立科学而有效的薪酬体系。在分析科技中介服务机构核心员工特征和主导需求的基础上,运用激励理论和薪酬管理中的重要思想,探讨了该类机构中... 详细信息

科技中介服务机构在向专业化、市场化和企业化转化的过程中,为激励、吸引和留住核心员工,必须建立科学而有效的薪酬体系。在分析科技中介服务机构核心员工特征和主导需求的基础上,运用激励理论和薪酬管理中的重要思想,探讨了该类机构中核心员工薪酬体系的设计原则和关键要素。

关键词：中介服务机构员工科技薪酬管理激励理论设计原则专业化企业化市场化特征和