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Synthesis of Novel Derivatives of (R)-Cysteine and Their Application in Asymmetric Reduction of Prochiral Ketones

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Chemical Research in Chinese Universities 2005年第5期21卷 536-539页

作者： WANG Hui pei wei-wei YE wei-ping The Key Laboratory of Bioorganic Chemistry and Molecular Engineering of Ministry of Education College of Chemistry and Molecular Engineering Peking University Beijing 100871 P. R. China

ovel chiral β-amino alcohols containing sulfide or sulfonyl groups were synthesized from （R）-cysteine. Their chiral induction in the asymmetric borane reduction of prochiral ketones was investigated. Optically active secondary alcohols with moderate or high e. e. values were obtained, and the causes of different enantioselectivities between these two sulfur-containing chiral β-amino alcohols were researched.

关键词： (R)-Cysteine Sulfide Sulfone Synthesis Asymmetric reduction

Review of Operational Control Strategy for DC Microgrids with Electric-hydrogen Hybrid Storage Systems

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CSEE Journal of Power and Energy Systems 2022年第2期8卷 329-346页

作者： wei pei Xue Zhang wei Deng Chenghong Tang Liangzhong Yao the Institute of Electrical Engineering Chinese Academy of SciencesBeijing 100190 University of Chinese Academy of Sciences Beijing 100049China the Institute of Electrical Engineering Chinese Academy of SciencesBeijing 100190China the NARI Group Corporation Nanjing 211106China the School of Electrical Engineering and Automation Wuhan UniversityWuhan 430072China

Hydrogen production from renewable energy sources(RESs)is one of the effective ways to achieve carbon peak and carbon *** order to ensure the efficient,reliable and stable operation of the DC microgrid(MG)with an electric-hydrogen hybrid energy storage system(ESS),the operational constraints and static dynamic characteristics of a hydrogen energy storage system(HESS)needs to be fully ***,different hydrogen production systems,using water electrolysis are compared,and the modeling method of the electrolyzer is *** operational control architecture of the DC MG with electric-hydrogen is *** with the working characteristics of the alkaline electrolyzer,the influence of hydrogen energy storage access on the operational mode of the DC MG is *** operational control strategies of the DC MG with electric-hydrogen hybrid ESS are classified and analyzed from four different aspects:static and dynamic characteristics of the hydrogen energy storage system,power distribution of the electric-hydrogen hybrid ESS and the efficiency optimization of hydrogen energy ***,the advantages of a modular hydrogen production system(HPS)are described,and the technical problems and research directions in the future are discussed.

关键词： Hydrogen energy DC microgrid modeling method operation control renewable energy sources

Operational Control of Low-voltage MTDC Systems in a Cyber-physical Environment

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CSEE Journal of Power and Energy Systems 2022年第6期8卷 1569-1582页

作者： wei Deng wei pei Ningning Li Xue Zhang Yin Yi Li Kong Institute of Electrical Engineering Chinese Academy of SciencesBeijing 100190China School of Electronic Electrical and Communication Engineering(EECE)University of Chinese Academy of SciencesBeijing 100049China

Based on the standardized cyber-physical modeling and communication system-IEC 61850,this paper establishes the operational control architecture of a low-voltage multi-terminal DC(LV-MTDC)*** coordinated operational control strategies,including power electronic transformer(PET),and voltage source converter(VSC),are *** a cyberphysical model of the system based on IEC 61850 is built,according to the application requirements of operational control in the LV-MTDC *** this basis,the implementation method of system operational control based on IEC 61850 is proposed,including the software/hardware design of the intelligent electronic device(IED),dispatching operations and uninterrupted power *** simulation environment is further built to verify the system operational control technology,and the test platform is used to carry out the actual *** research results show that the operational control technology for the LV-MTDC system proposed in this paper is feasible,which can guarantee the rapid and accurate information exchange of control commands and settings,and thus effectively realize the operational control of the LV-MTDC system under complex conditions.

关键词： Cyber-physical system distributed energy resources IEC 61850 intelligent electronic device low-voltage multi-terminal DC system

Spin-Flip Response Function of Finite Nuclei in a Fully Self-Consistent RPA Approach

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Chinese Physics Letters 2013年第5期30卷 33-36页

作者： WEN pei-wei CAO Li-Gang Institute of Modern Physics University of Chinese Academy of SciencesLanzhou 730000 Graduate University of Chinese Academy of Sciences Beijing 100049 Center of Theoretical Nuclear Physics National Laboratory of Heavy Ion Accelerator of LanzhouLanzhou 730000

The spin-flip response of finite nuclei is studied in a fully self-consistent Hartree–Fock plus random phase approximation (RPA) within the SLy5 Skyrme parameter set. The effect of J^(2) terms and spin-orbit interaction on the response function are discussed. The J^(2) terms are included/excluded at both the mean field and the excited state for self-consistency. The numerical results show that the J^(2) terms give a strong effect on the properties of the magnetic dipole response and the Gamow–Teller response. The spin-orbit residual interaction has almost no contribution to the spin-flip response according to our present study.

关键词： set interaction Hartree

Convenient Asymmetric Borane Reduction of Ketones Catalyzed by Simple Amino Alcohols and Corresponding Amino Acids

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Chinese Chemical Letters 2002年第12期13卷 1147-1148页

作者： Guo Bin SUN wei wei pei Hui WANG wei Ping YE College of Chemistry and Molecular Engineering Peking UniversityBeijing 100871

An asymmetric borane reduction of prochiral ketones catalyzed by simple amino alcohols and corresponding amino acids was examined to give alcohols with e.e. value up to 92% .

关键词： Enantioselective borane reduction amino alcohols amino acids ketones.

Optimization of Distributed Integrated Multi-energy System Considering Industrial Process Based on Energy Hub

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Journal of Modern Power Systems and Clean Energy 2020年第5期8卷 863-873页

作者： Yizhi Zhang Xiaojun Wang Jinghan He Yin Xu wei pei IEEE School of Electrical Engineering Beijing Jiaotong UniversityBeijing 100044China Institute of Electrical Engineering Chinese Academy of SciencesBeijing 100190China

As a typical scenario of distributed integrated multi-energy system(DIMS),industrial park contains complex production constraints and strong associations between industrial productions and energy *** industrial production process(IPP)consists of controllable subtasks and strict timing *** IPP as a control variable of optimal scheduling,it is an available approach that models the IPP as material flow into an extension energy hub(EH)to achieve the optimization of industrial *** this paper,considering the coupling between the production process and energy demands,a model of IPP is proposed by dividing the process into different adjustable steps,including continuous subtask,discrete subtask,and storage ***,a transport model of material flow is used to describe the IPP in an industrial park *** on the concept of EH,a universal extension EH model is proposed considering the coupling among electricity,heat,cooling,and ***,an optimal scheduling method for industrial park DIMS is proposed to improve the energy efficiency and operation ***,a case study of a typical battery factory is shown to illustrate the proposed *** simulation results demonstrate that such a method reduces the operation cost and accurately reflects the operation state of the industrial factory.

关键词： Distributed integrated multi-energy system(DIMS) industrial production process(IPP) energy hub(EH) optimal operation battery production

A Hybrid Deep Learning Scheme for Multi-Channel Sleep Stage Classification

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Computers, Materials & Continua 2022年第4期71卷 889-905页

作者： wei pei Yan Li Siuly Siuly Peng Wen School of Sciences University of Southern QueenslandToowoomba4350Australia School of Mechanical and Electrical Engineering University of Southern QueenslandToowoomba4350Australia

Sleep stage classification plays a significant role in the accurate diagnosis and treatment of sleep-related *** study aims to develop an efficient deep learning based scheme for correctly identifying sleep stages using multi-biological signals such as electroencephalography(EEG),electrocardiogram(ECG),electromyogram(EMG),and electrooculogram(EOG).Most of the prior studies in sleep stage classification focus on hand-crafted feature extraction *** hand-crafted feature extraction methods choose features manually from raw data,which is tedious,and these features are limited in their ability to balance efficiency and ***,most of the existing works on sleep staging are either single channel(a single-lead EEG may not contain enough information)or only EEG signal based which can not reveal more complicated physical features for reliable classification of various sleep *** study proposes an approach to combine Convolutional Neural Networks(CNNs)and Gated Recurrent Units(GRUs)that can discover hidden features from multi-biological signal data to recognize the different sleep stages *** the proposed scheme,the CNN is designed to extract concealed features from the multi-biological signals,and the GRU is employed to automatically learn the transition rules among different sleep *** that,the softmax layers are used to classify various sleep *** proposed method was tested on two publicly available databases:Sleep Heart Health Study(SHHS)and ***’s University Hospital/University College Dublin Sleep Apnoea(UCDDB).The experimental results reveal that the proposed model yields better performance compared to state-of-the-art *** proposed scheme will assist in building a new system to deal with multi-channel or multi-modal signal processing tasks in various applications.

关键词： Convolutional neural networks gated recurrent unit sleep stages multi-channel 1 Introduction

Isolation and Characterization of Acid-soluble Collagen and Pepsin-soluble Collagen from the Skin of Hybrid Sturgeon

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Journal of Wuhan University of Technology(Materials Science) 2019年第4期34卷 950-959页

作者： wei pei LI Dan Department of Chemical Engineering School of ChemistryChemical Engineering and Life SciencesWuhan University of TechnologyWuhan 430070China Department of Pharmaceutical Engineering School of ChemistryChemical Engineering and Life SciencesWuhan University of TechnologyWuhan 430070China The Amur Caviar Company Ltd. Kunming 650228China Hospital of Wuhan University of Technology Wuhan 430070China

By using the wastes fish skin of sturgeon processed as a raw material, a macromolecule biomaterial of collagen was extracted. Acid-soluble collagen(ASC) and pepsin-soluble collagen(PSC) were successfully isolated from the skin of hybrid sturgeon with two extraction methods. The yields of ASC and PSC based on the wet weight of skin were 5.73 ± 0.11% and 10.26 ± 0.39%, respectively. The denaturation and melting points of ASC(26.83 ℃ and 110.49 ℃) and PSC(26.54 ℃ and 102.99 ℃) were assessed by Circular dichroism(CD) and Differential scanning calorimetry(DSC). ASC and PSC appeared to be dense sheet-like film linked by random-coiled filaments under scanning electron microscopy(SEM). Sodium dodecyl sulfate-polyacrylamide gel electrophoresis(SDS-PAGE) and Fourier transform infrared spectroscopy(FTIR) confirmed that both the ASC and PSC were Type I collagen and maintained a complete triple helix structure. These results indicated that both ASC and PSC possessed good biological activity and could be widely used in medical biomaterials and other fields.

关键词： hybrid sturgeon acid-soluble collagen(ASC) pepsin-soluble collagen(PSC) isolation characterization

Microstructure and Mechanical Properties of Nodular Cast Iron Produced by Melted Metal Die Forging Process

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Journal of Iron and Steel Research International 2013年第6期20卷 58-62页

作者： LI Nan XING Shu-ming BAO pei-wei School of Mechanical Electronic and Control Engineering Beijing Jiaotong University

The microstructure and mechanical properties of nodular cast iron produced by the melted metal die forging process （MMDF for short） were experimentally *** main obtained results are ： the nodular cast iron produced by this process can be machined as easy as traditional one only if holding at the remained temperature for 4 h ; its strength and plasticity are obviously higher than those of traditional ones ; the graphite size arrived at grade 8 , and the graphite spheroidizing arrived at grade 1 or 2 , but a streamline molded distribution of the graphite slightly *** of the strength and plasticity increased with the pressure when the pressure holding time was larger than its critical value.A new way to produce high properties nodular cast iron was provided.

关键词： nodular cast iron squeeze casting liquid die forging microstructure property