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Catalytic Enantioselective Construction of 6-4 Ring-Junction All-Carbon Stereocenters and Mechanistic Insights

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Chinese Journal of Chemistry 2022年第15期40卷 1767-1776页

作者： Jia-Yin Wang Chen-Long Li Ting Xu Meng-Fan Li Wen-Juan Hao Shu-Jiang Tu Jianyi Wang Guigen Li Zhi-Xiang yu Bo Jiang School of Chemistry&Materials Science Jiangsu Normal UniversityXuzhouJiangsu 221116China College of Chemistry Peking UniversityBeijing 100871China Medical College Guangxi UniversityNanningGuangxi 530004China Institute of Chemistry&Biomedical Sciences Nanjing UniversityNanjingJiangsu 210093China Department of Chemistry and Biochemistry Texas Tech UniversityLubbockTexas 79409-1061United States

Comprehensive Summary Developing reactions for the synthesis of 6-6-4 and 6-4 carbocyclic scaffolds with a chiral quaternary center at the bridgehead position is highly desired,considering the existence of such skeletons in natural products with biological activities and the potential of using these molecules for downstream studies in chemical biology and medicinal *** here is accessing these target skeletons with high chemo-,regio-and enantio-selectivities through Pd(ll)/chiral N,N'-disulfonyl bisimidazoline(Bim)ligand-catalyzed asymmetric reaction of yne-allenones and arylboronic acids.

关键词： Asymmetric catalysis Palladium michael addition Chiral cyclobutenes Mechanism

Development of Biomimetic Synthesis of Propindilactone G

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Chinese Journal of Chemistry 2020年第11期38卷 1339-1352页

作者： yu Wang Bo Chen Xubiao He Jinghan Gui CAS Key Laboratory of Synthetic Chemistry of Natural Substances Center for Excellence in Molecular SynthesisShanghai Institute of Organic ChemistryUniversity of Chinese Academy of SciencesChinese Academy of SciencesShanghai 200032China

of main observation and conclusion The natural product propindilactone G is a complex Schisandra nortriterpenoid with a unique 5/5/7/6/5 pentacyclic *** full paper describes the development of concise biomimetic synthesis of propindilactone G from a known steroid *** key C19-OH intermediate was synthesized via Breslow and Suarez radical remote C—H ***-Meerwein rearrangement was subsequently utilized for the expansion of the B *** invert the configuration of the C1O tertiary alcohol,an intramolecular peroxide cyclization catalyzed by BF3-Et2O was *** 5/5 fused lactone system was then assembled in a biomimetic transesterification/oxa-michael addition *** work should provide experimental support for the proposed biosynthetic pathway and facilitate investigation of the biological activities of pro pindilactone G.

关键词： lactone utilized rearrangement

SIES:A Novel Implementation of Spiking Convolutional Neural Network Inference Engine on Field-Programmable Gate Array

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Journal of Computer Science & Technology 2020年第2期35卷 475-489页

作者： Shu-Quan Wang Lei Wang yu Deng Zhi-Jie Yang Sha-Sha Guo Zi-Yang Kang yu-Feng Guo Wei-Xia Xu College of Computer Science and Technology National University of Defense TechnologyChangsha 430041China

Neuromorphic computing is considered to be the future of machine learning,and it provides a new way of cognitive *** by the excellent performance of spiking neural networks(SNNs)on the fields of low-power consumption and parallel computing,many groups tried to simulate the SNN with the hardware ***,the efficiency of training SNNs with neuromorphic algorithms is not ideal *** this,michael et *** a method which can solve the problem with the help of DNN(deep neural network).With this method,we can easily convert a well-trained DNN into an SCNN(spiking convolutional neural network).So far,there is a little of work focusing on the hardware accelerating of *** motivation of this paper is to design an SNN processor to accelerate SNN inference for SNNs obtained by this DNN-to-SNN *** propose SIES(Spiking Neural Network Inference Engine for SCNN Accelerating).It uses a systolic array to accomplish the task of membrane potential increments *** integrates an optional hardware module of max-pooling to reduce additional data moving between the host and the *** also design a hardware data setup mechanism for the convolutional layer on the SIES with which we can minimize the time of input spikes *** implement the SIES on FPGA *** number of neurons it supports is up to 4000 while the synapses are *** SIES can run with the working frequency of 200 MHz,and its peak performance is 1.5625 TOPS.

关键词： spiking neural network(SNN) field-programmable gate array(FPGA) neuromorphic systolic array spiking convolutional neural network(SCNN) integrete and fire(I&F)model hardware accelerator

废三元锂离子电池正极材料脱锂渣的淀粉还原浸出动力学

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Transactions of Nonferrous Metals Society of China 2023年第2期33卷 619-631页

作者：李为轮陈永明李帅王长红李云赵天瑜 michael TRAVERSY 常聪介亚菲何静唐朝波杨声海中南大学冶金与环境学院长沙410083 The Robert M.Buchan Department of Mining Queen’s University25 Union StreetKingstonOntario K7L3N6Canada

以淀粉为还原剂从废三元锂离子电池(LIBs)正极材料脱锂渣中回收Ni、Co和Mn,并研究其浸出动力学和机理。系统地研究搅拌速率、浸出温度、H_(2)SO_(4)浓度和淀粉用量对Ni、Co和Mn浸出率的影响。结果表明,在搅拌速率为500 r/min、硫酸浓度... 详细信息

以淀粉为还原剂从废三元锂离子电池(LIBs)正极材料脱锂渣中回收Ni、Co和Mn,并研究其浸出动力学和机理。系统地研究搅拌速率、浸出温度、H_(2)SO_(4)浓度和淀粉用量对Ni、Co和Mn浸出率的影响。结果表明,在搅拌速率为500 r/min、硫酸浓度为1.5 mol/L、淀粉用量为6 g/L、浸出温度为80℃和浸出时间为60 min的优化条件下,Ni、Co和Mn的浸出率分别达到98.07%、96.52%和98.06%。根据冶金过程液固反应动力学模型,脱锂渣的浸出动力学可以用化学反应控制的未反应收缩核模型很好地进行描述。在浸出反应中,Ni、Co和Mn的表观反应活化能分别为93.32、102.84和95.68 k J/mol,H_(2)SO_(4)的表观反应级数分别为0.9225、1.0335和1.1285。淀粉容易制取、成本低,可取代传统还原剂用于从废三元锂电池中提取有价金属。

关键词：废旧锂离子电池浸出动力学脱锂渣 H2SO4-淀粉溶液化学反应控制

Efficient prediction of workpiece-fixture contact forces using the rigid body model

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Efficient prediction of workpiece-fixture contact forces usi...

The commutant and similarity invariant of analytic Toeplitz operators on Bergman space

第五届海内外青年设计与制造科学会议

作者： michael yu Wang Diana M.Pelinescu Department of Automation and Computer-Aided Engineering The Chinese University of Hong Kong ShatinN.T.Hong Kong Department of Mechanical Engineering University of Maryland College Park MD 20742 USA

＜正＞Prediction of workpiece-fixture contact forces is important in fixture design since they define the fixture stability during clamping and strongly influence workpiece accuracy during manufacturing. This paper presents a solution method for predicting the normal and frictional contact forces between workpiece-fixture contacts. The fixture and workpiece are considered to be rigid bodies, and the model solution is solved as a constrained quadratic optimization by applying the minimum norm principle. The model reveals some intricate properties of the passive contact forces, including the potential of a locator release and the history dependency during a sequence of clamping and/or external force loading. Model predictions are shown to be in good agreement with known results of an elastic-contact model prediction and experimental measurements. This presented method is conceptually simple and computationally efficient. It is particularly useful in the early stages of fixture design and process planning.

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Science China Mathematics 2007年第5期50卷 651-664页

作者： Chun-Ian JIANG yu-cheng Li Department of Mathematics Hebei Normal UniversityShijiazhuang 050016China

The famous von Neumann-Wold Theorem tells us that each analytic Toeplitz operator with n + 1-Blaschke factors is unitary to n + 1 copies of the unilateral shift on the Hardy space. It is obvious that the von Neumann-Wold Theorem does not hold in the Bergman space. In this paper, using the basis constructed by michael and Zhu on the Bergman space we prove that each analytic Toeplitz operator Mb(z) is similar to n + 1 copies of the Bergman shift if and only if B(z) is an n + 1-Blaschke product. Prom the above theorem, we characterize the similarity invariant of some analytic Toeplitz operators by using K0-group term.

关键词： Bergman space analytic Toeplitz operators invariant subspace commutant similarity invariant K0-group

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中道西用:中国管理学自主知识体系构建方向

经济管理 2023年第10期45卷 5-26页

作者：余菁中国社会科学院工业经济研究所北京100006

长期以来,中国管理学学术界沿着中西会通或东西交融的方向来发展中国管理理论。过去十余年,又涌现了发展中国情境下的管理理论与本土化中国管理理论的强烈自觉。然而,中国管理理论知识体系为西方理论及其话语体系所主导的被动局面一直... 详细信息

长期以来,中国管理学学术界沿着中西会通或东西交融的方向来发展中国管理理论。过去十余年,又涌现了发展中国情境下的管理理论与本土化中国管理理论的强烈自觉。然而,中国管理理论知识体系为西方理论及其话语体系所主导的被动局面一直未得到有效改观。本文认为,突破中国管理理论创新难的困局,需要转向以“中道”为主且兼具“西用”特质的发展方向。文中的“中道西用”,意指中国企业管理理论知识的发展应该紧密结合中国式现代化的伟大历史进程,全面深入中国企业管理实践活动中去发现和探究高理论价值的现象。未来,中国管理学研究者应加强对中国管理学自主性的认同,通过重置研究标尺和聚焦弱相互作用来深入充斥隐性知识的中国企业管理实践场景,大力探索和发展能够有效应对当下人类与科技智能共生的不确定性的新管理理论知识。只有聚焦中国企业管理实践中与文化价值观、与人紧密相关的丰裕隐性知识,才有可能驾驭和超越西方管理理论中主要与有形的物化因素、与工具理性相关的显性知识,持续生成符合中国国情和有重要时代意义的管理理论知识,进而指引中国企业在更大范围和更高层次上加快推进中国式管理现代化的实践。

关键词：管理理论中国式现代化中道西用

Modification of Nano-alumina Surface by michael Addition Reaction

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Chinese Chemical Letters 2006年第2期17卷 251-252页

作者： Jie ZHANG Jian yu Zhao Xia GUO Institute of Polymer Science and Engineering Department of Chemical EngineeringSchool of Materials Science and Engineering Tsinghua University Beijing 100084

A general method for modification of nano-alumina surface is investigated using michael addition reaction with α,β-unsaturated carbonyl compounds.

关键词： Alumina surface modification michael addition reaction carbonyl compounds ester.

A systematic study of the whole genome sequence of Amycolatopsis methanolica strain 239T provides an insight into its physiological and taxonomic properties which correlate with its position in the genus

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Synthetic and Systems Biotechnology 2016年第3期1卷 169-186页

作者： Biao Tang Feng Xie Wei Zhao Jian Wang Shengwang Dai Huajun Zheng Xiaoming Ding Xufeng Cen Haican Liu yucong yu Haokui Zhou Yan Zhou Lixin Zhang michael Goodfellow Guo-Ping Zhao State Key Laboratory of Genetic Engineering Department of MicrobiologySchool of Life Sciences and Institute of Biomedical SciencesFudan UniversityShanghai200438China CAS-Key Laboratory of Synthetic Biology Institute of Plant Physiology and EcologyShanghai Institutes for Biological SciencesChinese Academy of SciencesShanghai200031China CAS-Key Laboratory of Pathogenic Microbiology and Immunology Institute of MicrobiologyChinese Academy of SciencesNo.1 Beichen West RoadChaoyang DistrictBeijing100101China Shanghai-MOST Key Laboratory of Disease and Health Genomics Chinese National Human Genome Center at ShanghaiShanghai201203China State Key Laboratory for Infectious Diseases Prevention and Control Collaborative Innovation Center for Diagnosis and Treatment of Infectious DiseasesNational Institute for Communicable Disease Control and PreventionChinese Center for Disease Control and PreventionBeijingChina Department of Microbiology and Li Ka Shing Institute of Health Sciences The Chinese University of Hong KongPrince of Wales HospitalShatinNew TerritoriesHong Kong SARChina School of Biology University of NewcastleNewcastle upon TyneNE17RUUK

The complete genome of methanol-utilizing Amycolatopsis methanolica strain 239T was generated,revealing a single 7,237,391 nucleotide circular chromosome with 7074 annotated protein-coding sequences(CDSs).Comparative analyses against the complete genome sequences of Amycolatopsis japonica strain MG417-CF17T,Amycolatopsis mediterranei strain U32 and Amycolatopsis orientalis strain HCCB10007 revealed a broad spectrum of genomic structures,including various genome sizes,core/quasi-core/non-core configurations and different kinds of *** polyketide synthase gene clusters were absent from the *** genome,12 gene clusters related to the biosynthesis of other specialized(secondary)metabolites were *** pathways attributable to the facultative methylotrophic physiology of *** strain 239T,including both the mdo/mscR encoded methanol oxidation and the hps/hpi encoded formaldehyde assimilation via the ribulose monophosphate cycle,were identified together with evidence that the latter might be the result of horizontal gene *** analyses based on 16S rDNA or orthologues of AMETH_3452,a novel actinobacterial class-specific conserved gene against 62 or 18 Amycolatopsis type strains,respectively,revealed three major phyletic lineages,namely the mesophilic or moderately thermophilic *** subclade(AOS),the mesophilic Amycolatopsis taiwanensis subclade(ATS)and the thermophilic *** subclade(AMS).The distinct growth temperatures of members of the subclades correlated with corresponding genetic variations in their encoded compatible *** study shows the value of integrating conventional taxonomic with whole genome sequence data.

关键词： Amycolatopsis methanolica Complete genome sequence One carbon metabolism Sub-generic phyletic clades AOS ATS AMS