检索结果-南通市图书馆

Chinese Chemical Letters 2006年第1期17卷 109-112页

作者： Chang Yuan HU Feng yi LI rong Bin zhang Li HUA Department of Chemistry Nanchang University Nanchang 330047

Uniform Ni-B amorphous alloys about 14 nm have been prepared on CNTs-A support,named Ni-B/CNTs-A. In comparison with the Ni-B/CNTs amorphous catalyst, Ni-B/CNTs-A showed higher nickel loading, determined by ICP and be... 详细信息

关键词： CNTs aniline Ni-B amorphous alloy catalyst acetylene selective hydrogenation.

Validity and reliability testing of the Chinese (mainland) version of the 39-item Parkinson's Disease Questionnaire (PDQ-39)

在线全文

学校读者我要写书评

暂无评论

Journal of Zhejiang University-Science B(Biomedicine & Biotechnology) 2010年第7期11卷 531-538页

作者： Wei LUO Xiao-hong GUI Bo WANG Wen-ying zhang Zhi-yuan OUYANG yi GUO Bao-rong zhang Mei-ping DING Department of Neurology the Second Affiliated Hospital School of Medicine Zhejiang University Hangzhou 310009 China

The 39-item Parkinson's Disease Questionnaire (PDQ-39) has been tested in many languages, but not in Chinese mainland. We aimed to assess the Chinese (mainland) version of the PDQ-39. Seventy-one subjects with Parkinson's disease (PD) completed the PDQ-39 and the Medical Outcomes Study 36-item Short Form Health Survey (SF-36). All subjects were retested with the PDQ-39 a week later. The united Parkinson's disease rating scale (UPDRS) and the Hoehn and Yahr (H & Y) scale were also used to evaluate the subjects. Reliability was assessed by Cron- bach's α and intra-class correlation coefficient (ICC). Validity was examined in terms of agreement with SF-36, UPDRS, and H & Y scales. The Chinese (mainland) version of the PDQ-39 demonstrated acceptable reliability (Cronbach's α: 0.84-0.88; ICC: 0.56-0.82). The item-total correlations (0.33-0.88) and scaling success rates (77.56%) indicated satisfactory convergent and discriminant validity of the PDQ-39 items. The correlations between related constructs of the PDQ-39 and UPDRS (r=0.44-0.68) and between those of the PDQ-39 and SF-36 (r=(-0.46)-(-0.69)) were all statistically significant (P<0.01). Except for stigma, cognitions, and bodily discomfort, all other dimensions of the PDQ-39 significantly discriminated patients at different H & Y stages indicated by the H & Y scale. Although our observations indicate that some problematic subscales of this version of the PDQ-39 could be improved upon, this study suggests acceptable reliability and validity of the Chinese (mainland) version of the PDQ-39.

关键词： 39-item Parkinson’s Disease Questionnaire (PDQ-39) Quality of life Validity Reliability

Bond-distorted Orbitals and Their Application to Benzene

在线全文

学校读者我要写书评

暂无评论

Chemical Research in Chinese Universities 1993年第4期9卷 335-338页

作者： MO yi-rong , WU Wei and zhang Qian-er (Department of Chemistry, Xiamen University, Xiamen, 361005)

The present paper covers a kind of localized orbitals, namely bond-distorted or-bitals in the valence bond calculation. Test calculation on benzene is reported. The results indicate that Dewar structures are important... 详细信息

关键词： Ab initio Valence bond Bond-distorted orbital (EDO) Benzene

High-throughput screening of CO_(2) cycloaddition MOF catalyst with an explainable machine learning model

在线全文

学校读者我要写书评

暂无评论

Green Energy & Environment 2025年第1期10卷 132-138页

作者： Xuefeng Bai yi Li Yabo Xie Qiancheng Chen Xin zhang Jian-rong Li Beijing Key Laboratory for Green Catalysis and Separation and Department of Chemical Engineering College of Materials Science&EngineeringBeijing University of TechnologyBeijing100124China

The high porosity and tunable chemical functionality of metal-organic frameworks(MOFs)make it a promising catalyst design ***-throughput screening of catalytic performance is feasible since the large MOF structure database is *** this study,we report a machine learning model for high-throughput screening of MOF catalysts for the CO_(2) cycloaddition *** descriptors for model training were judiciously chosen according to the reaction mechanism,which leads to high accuracy up to 97%for the 75%quantile of the training set as the classification *** feature contribution was further evaluated with SHAP and PDP analysis to provide a certain physical understanding.12,415 hypothetical MOF structures and 100 reported MOFs were evaluated under 100℃ and 1 bar within one day using the model,and 239 potentially efficient catalysts were *** them,MOF-76(Y)achieved the top performance experimentally among reported MOFs,in good agreement with the prediction.

关键词： Metal-organic frameworks High-throughput screening Machine learning Explainable model CO_(2)cycloaddition

Self-assembly of two pairs of homochiral M2L4 coordination capsules with varied confined space using Tr?ger's base ligands

在线全文

学校读者我要写书评

暂无评论

Chinese Chemical Letters 2025年第2期36卷 360-365页

作者： yi Zhou Wei zhang rong Fu Jiaxin Dong Yuxuan Liu Zihang Song Han Han Kang Cai College of Chemistry Nankai University Department of Chemistry Northwestern University Department of Chemistry The University of Hong Kong

Chiral coordination molecular cages/capsules with discrete nanoconfined chiral cavities demonstrate significant potential applications across various fields. In this study, we utilized Tr?ger's base as the building block to design and synthesize two pairs of enantiopure ligands. These ligands were then self-assembled with Pd(II) ions through chiral self-sorting coordination, resulting in the formation of two pairs of homochiral M2L4-type coordination molecular capsules. Notably, due to differences in the substitution positions on the Tr?ger's base, these two pairs of enantiomeric coordination molecular capsules exhibited distinct levels of cavity closures, cavity sizes, and host-guest recognition properties. This research offers valuable insights into the construction of novel chiral molecular capsules and the regulation of confined cavities.

关键词： Chirality Host-guest recognition Metal-organic capsule Self-sorting Tröger's base

Ⅱ conjugation in the butadiene

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

Chinese Journal of Chemistry 1995年第1期13卷 27-32页

作者： MO, yi-rong WU, Wei zhang, Qian-ErDepartment of Chemistry, Xiamen University, Xiamen, Fujian 361005, China

The π electronic delocalization in trans-C4H6 and cis-C4H6 has been investigated in the frame of ab initio valence bond theory with 6-31G basis set. The result shows that the Csp2-Csp2 single bond length (1.506 A) is only about 0.024 A shorter than the Csp3-Csp3 bond, thus the central bond length shortening would be mainly due to π conjugation. The theoretical resonance energies of the trans-C4H6 and cis-C4H6 are 8.48 and 7.44 kcal/mol, respectively.

关键词： Butadiene valence bond delocalization.

Field-effect transistors based on two-dimensional materials for logic applications

在线全文

学校读者我要写书评

暂无评论

Chinese Physics B 2013年第9期22卷 147-161页

作者：王欣然施毅张荣 National Laboratory of Microstructures and School of Electronic Science and Engineering Nanjing University

Field-effect transistors （FETs） for logic applications, graphene and MoS2, are discussed. These materials have based on two representative two-dimensional （2D） materials, drastically different properties and require different consider- ations. The unique band structure of graphene necessitates engineering of the Dirac point, including the opening of the bandgap, the doping and the interface, before the graphene can be used in logic applications. On the other hand, MoS2 is a semiconductor, and its electron transport depends heavily on the surface properties, the number of layers, and the carrier density. Finally, we discuss the prospects for the future developments in 2D material transistors.

关键词： graphene MoS2 two-dimensional (2D) materials field-effect transistors

Application of Second-Order Cone Programming Theory to Robust Adaptive Beamforming

在线全文

学校读者我要写书评

暂无评论

Application of Second-Order Cone Programming Theory to Robus...

Partial multi-label learning via label-specific feature corrections

2015年中国智能自动化学术会议

作者： rong-yi zhang Hai-Yan Song Mechitrone Engineering College Heilongjiang Institute of Technology School of Electrical and Information Engineering Heilongjiang Institute of Technology

Due to the array steering vector errors and small-sample errors and so on,the performance of the Standard Capon Beamformer(SCB) may become worse than that of the Conventional Beamformer(CBF) in practical engineering applications. Nowadays, almost all existing algorithms to improve the robustness of SCB utilize the steepest descent method, conjugate gradient method, least mean squares(LMS) method and so on. However, most of them have the slow convergence and inefficient computation. Aiming at the above problems, this paper presents a unified process to solve them by the second-order cone programming(SOCP) theory,which can not only enhance the convergence speed but also improve the calculation accuracy so as to overcome the shortcomings of the previous optimization solutions effectively. It turns out that most adaptive beamforming algorithms involve a nonconvex problem which is minimization of a quadratic function subject to infinitely many non-convex quadratic constraints. In this paper, it is shown that the proposed algorithm can be reformulated in a convex form as the so-called SCOP and solved efficiently(in polynomial time) using the well-established interior point ***, computer simulations show the algorithm’s excellent performance as compared with existing adaptive beamforming algorithms via the computer simulation examples.

关键词： Second-order cone programming Robust adaptive beamforming Sedumi

来源： cnki会议评论

在线全文

cnki会议

学校读者我要写书评

暂无评论

Science China(Information Sciences) 2025年第03期68卷 95-109页

作者： Jun-yi HANG Min-Ling zhang School of Computer Science and Engineering Southeast University Key Laboratory of Computer Network and Information Integration(Southeast University) Ministry of Education

Partial multi-label learning（PML） allows learning from rich-semantic objects with inaccurate annotations, where a set of candidate labels are assigned to each training example but only some of them are valid. Existing approaches rely on disambiguation to tackle the PML problem, which aims to correct noisy candidate labels by recovering the ground-truth labeling information ahead of prediction model induction. However, this dominant strategy might be suboptimal as it usually needs extra assumptions that cannot be fully satisfied in real-world scenarios. Instead of label correction, we investigate another strategy to tackle the PML problem, where the potential ambiguity in PML data is eliminated by correcting instance features in a label-specific manner. Accordingly, a simple yet effective approach named PASE, i.e., partial multi-label learning via label-specific feature corrections, is proposed. Under a meta-learning framework, PASElearns to exert label-specific feature corrections so that potential ambiguity specific to each class label can be eliminated and the desired prediction model can be induced on these corrected instance features with the provided candidate labels. Comprehensive experiments on a wide range of synthetic and real-world data sets validate the effectiveness of the proposed approach.

关键词： machine learning multi-label learning partial multi-label learning label-specific features feature correction

同方期刊数据库

General synthesis of a dual-atomic-site catalyst library

在线全文

学校读者我要写书评

暂无评论

Science China Materials 2025年第2期68卷 679-680页

作者： Jingfang zhang yi Huang School of Chemical Engineering&Pharmacy Wuhan Institute of TechnologyWuhan 430205China College of Chemistry Central China Normal UniversityWuhan 430079China

Single-atom catalysts(SACs),as a bridge between homogeneous and heterogeneous catalysts,have attracted tremendous attention over the past *** atomically dispersed metal active sites,SACs possess maximum atom utilization efficiency and exceptionally high activity towards various catalytic reactions[1].Compared with their nanoparticle counterparts,the unique but uniform configurations of the catalytic sites endow SACs with great potential for mechanism investigation at the atomic level[2,3].Despite of these advantages,SACs are facing the problem of linear scaling relations between intermediates in terms of complicated reactions involving co-adsorption of *** is difficult for a single-atom site to participate in all catalytic steps with high efficiencies,especially for some reactions that need adjacent active sites[4].In this regard,dualatomic-site catalysts(DACs)are emerging as a fascinating frontier in heterogeneous catalysis[5].It has been verified that the synergistic effect of the adjacent atomic pairs in DACs can break the linear scaling relations and optimize the adsorption energy of different intermediates,thus improving the intrinsic catalytic ***,it is of great significance to develop a general synthetic strategy for DACs.

关键词： atomic adsorption synthesis