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Precise Assembly and Supramolecular Catalysis of Tetragonal-and Trigonal-Elongated Octahedral Coordination Containers

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CCS Chemistry 2022年第3期4卷 1098-1107页

作者： tian-pu sheng Can He Zhenqiang Wang Guo-Zong Zheng Feng-Rong Dai Zhong-Ning Chen State Key Laboratory of Structural Chemistry Fujian Institute of Research on the Structure of MatterChinese Academy of SciencesFuzhouFujian 350002 University of Chinese Academy of Sciences Beijing 100049 Churchill-Haines Laboratories Department of ChemistryCenter for Fluorinated Functional MaterialsUniversity of South DakotaVermillionSD 57069-2390

The construction of distorted or irregular coordination polyhedrons with specific shapes and functionalities is highly ***,we demonstrate a viable strategy for attaining a severely distorted octahedral coordination container through precise geometrical manipulation of its nanocavity along the C_(3) or C4 axis to turn on its supramolecular *** constructed a tetragonal-elongated octahedral coordination container utilizing sulfonylcalix[4]arene-capped Co4 units as six vertexes and tetragonalelongated from single-arm lengthened 5-[(4-carboxybenzyl)amino]isophthalate(L)as eight triangular *** the concomitant introduction of C_(3)-symmetry cyclohexane-1,3,5-tricarboxylate as a secondary linker to construct two equilateral triangular base surfaces and L to build six isosceles triangular side planes,trigonal antiprismatic architecture(trigonal-elongated octahedron)was *** elongated octahedral containers exhibited distinctly higher binding capacity and stronger binding affinity toward reaction substrates than that of regular octahedral containers;thus,promoting geometry-dependent catalytic *** geometrical manipulation strategy provides a viable approach for the convenient design of metal–organic materials with specific functionalities.

关键词： coordination containers host-guest interaction supramolecular catalysis acid-base dual catalysis Knoevenagel condensation elongated coordination octahedron

Palladium-catalyzed asymmetric allylic C–H alkylation of 1,4-dienes and glycine Schiff bases

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Science China Chemistry 2020年第4期63卷 454-459页

作者： tian-Ci Wang pu-sheng Wang Liu-Zhu Gong Hefei National Laboratory for Physical Sciences at the Microscale and Department of Chemistry University of Science and Technology of ChinaHefei 230026China Center for Excellence in Molecular Synthesis of Chinese Academy of Sciences Hefei 230026China

A highly regio-and enantioselective allylic C–H alkylation of 1,4-dienes with glycine Schiff bases has been established by chiral palladium-phosphoramidite catalysis. This reaction can proceed under mild conditions and tolerate a wide scope of 1,4-dienes,delivering structurally diverse chiral β-branched α-amino acid surrogates in moderate to high yields and with high levels of regio-, Z/E-, diastereo-and enantioselectivities.

关键词： asymmetric catalysis palladium allylic C–H alkylation 1,4-diene glycine Schiff base

Access to chiral homoallylic vicinal diols from carbonyl allylation of aldehydes with allyl ethers via palladium-catalyzed allylic C-H borylation

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Science China Chemistry 2022年第2期65卷 298-303页

作者： tian-Ci Wang pu-sheng Wang Dian-Feng Chen Liu-Zhu Gong Hefei National Laboratory for Physical Sciences at the Microscale and Department of Chemistry University of Science and Technology of ChinaHefei 230026China Center for Excellence in Molecular Synthesis of CAS Hefei 230026China

Chiral homoallylic vicinal diols are found in many bioactive compounds and are among the most versatile functional groups in organic chemistry. Here, we describe an asymmetric carbonyl allylation of aldehydes with allyl ethers proceeding via allylic C-H borylation enabled by palladium and chiral phosphoric acid sequential catalysis, providing facile access to homoallylic vicinal anti-diols in high yields and with excellent stereoselectivity. This protocol enables the total synthesis of aigialomycin D to be finished within 7 steps.

关键词： asymmetric catalysis palladium allylic C–H borylation allyl ethers chiral phosphoric acid aldehydes

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城市中压配电网辐射网络的优化布线研究

东北电力大学学报 2013年第1期33卷 65-71页

作者：黄大为田圃昇李雅杨海波沈植学东北电力大学电气工程学院吉林吉林132012 杭州市电业局浙江杭州310000 卫辉市供电局河南卫辉453100

城市中压配电网规划是一个多目标、非线性、多阶段的复杂优化问题。随着我国城市化进程的加快,城市配电网建设存在供电范围、供电可靠性不能满足城市发展要求的现象。结合GIS提供的空间数据信息,给出了确定辐射网络初始布线集的方法;提... 详细信息

城市中压配电网规划是一个多目标、非线性、多阶段的复杂优化问题。随着我国城市化进程的加快,城市配电网建设存在供电范围、供电可靠性不能满足城市发展要求的现象。结合GIS提供的空间数据信息,给出了确定辐射网络初始布线集的方法;提出了基于改进最小生成树算法的辐射网络优化布线方法。该方法可以有效解决搜索过程中电能损耗费用对优化目标值的影响,以及交叉节点问题,通过算例的比较分析验证了该方法的有效性。

关键词：配电网 GIS 最小生成树

Functional analysis of the orphan genes Tssor-3 and Tssor-4 in male Plutella xylostella

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Journal of Integrative Agriculture 2021年第7期20卷 1880-1888页

作者： LI tian-pu ZHANG Li-wen LI Ya-qing YOU Min-sheng ZHAO Qian State Key Laboratory of Ecological Pest Control for Fujian-Taiwan Crops Institute of Applied EcologyFujian Agriculture and Forestry UniversityFuzhou 350002P.R.China Joint International Research Laboratory of Ecological Pest Control Ministry of EducationFuzhou 350002P.R.China Key Laboratory of Integrated Pest Management for Fujian-Taiwan Crops Ministry of Agriculture and Rural AffairsFuzhou 350002P.R.China

Orphan genes are genes with no sequence homologues in other species. Here, we identified two orphan genes, namely, Tssor-3 and Tssor-4, in Plutella xylostella. Both genes contained a signal peptide sequence, suggesting their functions as secreted proteins. Expression pattern analysis based on real-time quantitative PCR(qPCR) showed that both orphan genes were specifically expressed in all male gonads except the testes. The expression of both the orphan genes peaked at the male adult stage. Immunofluorescence assays suggested that the two proteins were seminal proteins, indicating their potential roles in male reproductive regulation. To further explain their functions, we knocked down the expression of these two genes by RNA interference(RNAi). The results showed that the expression of Tssor-3 and Tssor-4 was significantly downregulated at 24 h after injection compared to that of the controls. Biological assays showed that the number of laid eggs and the hatching rate of offspring eggs were significantly reduced when the expression of Tssor-3 and Tssor-4 was reduced, suggesting that the two orphan genes played a role in male fertility in P. xylostella. Our results provide evidence that orphan genes are involved in male reproductive regulation, which is important for male fitness during evolution.

关键词： Plutella xylostella orphan genes male fertility RNA interference

Design of a unified rendering shader for mobile device

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The Journal of China Universities of Posts and Telecommunications 2019年第3期26卷 81-90页

作者： Jiang Lin tian Rujia Yang Bowen tian pu Integrated Circuit Laboratory Xi'an University of Science and Technology Xi'an 710154 China School of Electronic Engineering Xi'an University of Posts and Telecommunications Xi'an 710121 China

Real-time graphics processing is all along a crucial task of mobile device, and it is conventionally supported by programmable graphics processing unit(Gpu). These Gpus are designed to flexibly support vertex and pixel processing with classic techniques such as on-chip cache and dynamic programmable pipelining. However, it is difficult for the vertex shader and pixel shader to achieve high utilization of hardware resources, even though there is a certain balance by reasonable processor quantity ratio. In this paper, a unified render shader with a very long instruction word(VLIW) processor was designed. The viewport transformation algorithm and the Mipmap mapping algorithm are respectively mapped on the shader, with the purpose of providing an energy-efficient and flexible hardware platform for graphics processing in mobile device. The implemented operating frequency is up to 134 MHz on Xilinx XC7 Z045-2-FFG900 field programmable gate array(FPGA), and unified architecture shader has a performance of 134 Mpixels/s in pixel fill rate, 546 Mtexels/s in texel fill rate.

关键词： vertex shading pixel shader VLIW mobile device Gpu

A CLASS OF MODIFIED BROYDEN ALGORITHMS

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Journal of Computational Mathematics 1994年第4期12卷 366-379页

作者： pu, DG tian, WW SHANGHAI INST RAILWAY TECHNOL DEPT MATHSHANGHAIPEOPLES R CHINA SHANGHAI UNIV SCI & TECHNOL DEPT MATHSHANGHAIPEOPLES R CHINA

In this paper we dicuss the convergence of the modified Broyden algorithms. We prove that the algorithms are globally convergent for the continuous differentiable function and the rate of convergence of the algorithms is one-step superlinear and n-step second-order for the uniformly convex objective function. From the discussion of this paper, we may get some convergence properties of the Broyden algorithms.

关键词： CLASS Powell Fletcher BFGS minimization convergent constrained demon exact symmetric

Sulfonylcalix[4]arene-based Coordination Supercontainers

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Chinese Journal of Structural Chemistry 2020年第12期39卷 2077-2084,2053页

作者： HE Can sheng tian-pu DAI Feng-Rong CHEN Zhong-Ning College of Chemistry and Materials Science Fujian Normal UniversityFuzhou 350007China State Key Laboratory of Structural Chemistry Fujian Institute of Research on the Structure of MatterChinese Academy of SciencesFuzhou 350002China

Sulfonylcalix[4]arenes-based coordination containers,namely metal-organic supercontainers(MOSCs),are a new class of coordination containers constructed from the self-assembly of divalent metal ions,suitable carboxylate linkers,and sulfonylcalix[4]arenes container *** feature both endo cavity surrounded by carboxylate linkers and exo cavities originated from the upper rim of sulfonylcalix[4]*** molecular topologies and endo cavity of MOSCs are tuneable via judicious design of carboxylate linkers,while the modulation of endo cavity are accessible by chemical modification on the para substituent group of the sulfonylcalix[4]*** this paper,recent advances and typical examples of design and functionalization of MOSCs are presented.

关键词： coordination container sulfonylcalixarene metal-organic supercontainer self-assembly

Impact of Stable Protein-protein Interaction on Protein Conformational Space

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Chemical Research in Chinese Universities 2015年第1期31卷 149-155页

作者： LI Wenzhao MENG Wei tian pu College of Life Science Key Laboratory of Molecular Enzymology and Engineering Ministry of Education Jilin University Changchun 130012 P. R. China

Backbone dihedral angle based clustering approach was applied to investigate the effect of protein complexation on backbone conformational space and the effect on protein dynamics. Three representative enzyme-inhibitor complexes and their comprised proteins were used as models for small- and moderate-sized globular proteins to compare available backbone conformational space before and after complexation. Microsecond time scale molecular dynamic simulations were generated to ensure sufficient statistics. The result suggests that stable protein-protein interactions lead to redistribution of protein backbone mobility and restriction of the protein backbone conformational space, especially for short time scale motions. Surprisingly, these effects are found to be uncorrelated with protein-protein interaction surface. Consistent with many experimental and computational observations, our results indicate that both induced-fit and conformational selection models play roles in stable protein complexation process, with the dominant role being different for different protein complexes.

关键词： Protein-protein interaction Conformational space Backbone dynamics Molecular dynamics simulation