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The First Total Synthesis of Natural 6β-Cinnamoyloxy-1α- hydroxy-5, 10-bis-epi-eudesm-4-en-3-one

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Chinese Chemical Letters 2006年第10期17卷 1290-1292页

作者： chen zhang guo jun ZHEN jin chun chen li jing FANG yu lin li State Key Laboratory of Applied Organic Chemistry Lanzhou University Lanzhou 730000

The first total synthesis of natural 6β-cinnamoyloxy-1α-hydroxy-5, 10-bis-epi- eudesm-4-en-3-one （1）, a highly complex natural eudesmane, was described.

关键词： 6β-Cinnamoyloxy-1α-hydroxy-5,10-bis-epi-eudesm-4-en-3-one C- 1 oxygenated eudesmane total synthesis.

A simple and efficient synthesis of the valsartan

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Chinese Chemical Letters 2008年第7期19卷 759-761页

作者： chen Xi zhang guo jun zheng Fu Qiang Bi yu lin li State Key Laboratory of Applied Organic Chemistry and Institute of Organic Chemistry Lanzhou University Lanzhou 730000 China

Valsartan 1, one of the most important agents used in antihypertensive therapy today, was synthesized starting from L-valin methyl ester hydrochloride 2 through four steps in an overall yield of 60%. The key step involves the palladium-catalyzed Suzuki coupling. This method overcomes many of the drawbacks associated with the previously reported syntheses and is more suitable for industrial production.

关键词： Valsartan Antihypertensive L-Valin methyl ester hydrochlofide Synthesis Suzuki coupling

Preface:special topic on rechargeable battery technology

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Science China Chemistry 2024年第1期67卷 1-3页

作者： yu-guo guo Qiang zhang jun chen li-jun Wan CAS Key Laboratory of Molecular Nanostructure and Nanotechnology CAS Research/Education Center for Excellence in Molecular SciencesBeijing National Laboratory for Molecular Sciences(BNLMS)Institute of ChemistryChinese Academy of Sciences(CAS)Beijing 100190China University of Chinese Academy of Sciences Beijing 100049China Beijing Key Laboratory of Green Chemical Reaction Engineering and Technology Department of Chemical EngineeringTsinghua UniversityBeijing 100084China Frontiers Science Center for New Organic Matter Renewable Energy Conversion and Storage Center(RECAST)Haihe Laboratory of Sustainable Chemical TransformationsKey Laboratory of Advanced Energy Materials Chemistry(Ministry of Education)College of ChemistryNankai UniversityTianjin 300071China

Rechargeable batteries play a major role in the transition from fossil energy to renewable energy and are considered the key-enabling decarbonization technology for several industries,including electronics,transportat... 详细信息

关键词： battery artificial technology

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Quantitative characterization of shale pore connectivity and controlling factors using spontaneous imbibition combined with nuclear magnetic resonance T_(2)and T_(1)-T_(2)

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Petroleum Science 2023年第4期20卷 1947-1960页

作者： Peng-Fei zhang Shuang-Fang Lu jun-Qian li Xiang-chun Chang jun-Jian zhang yu-Mao Pang Zi-Zhi lin guo chen Ya-Jie Yin yu-Qi liu College of Earth Science and Engineering Shandong University of Science and TechnologyQingdao266590ShandongChina Sanya Offshore Oil&Gas Research Institute Northeast Petroleum UniversitySanyaHainan572025China Key Laboratory of Deep Oil and Gas China University of Petroleum(East China)Qingdao266580ShandongChina College of Resources and Environment Yangtze UniversityWuhan430100HubeiChina

Shale oil can be extracted from shale by using interconnected pore *** migration of hydrocarbon molecules within the shale is controlled by pore ***,assessing the pore connectivity of shale oil reservoirs is *** characterize pore connectivity and clarify its controlling factors,this study used spontaneous imbibition(SI)combined with nuclear magnetic resonance(NMR)T_(2)and T_(1)-T_(2)technologies on shale oil reservoirs selected from the Shahejie Formation in the Dongying Sag,Bohai Bay *** to the findings,the SI processes of shales include fast-rising,slow-rising,and stable *** fast-rising stage denotes pore *** shales studied have poor connectivity,with lower imbibition slopes and connected porosity ratios,but large effective *** the SI process,micropores have the highest imbibition saturation,followed by mesopores and ***,n-dodecane ingested into micropores appears primarily as adsorbed,whereas n-dodecane appears primarily as free states in mesopores and macropores during the SI *** pore connectivity of the shales under study is primarily controlled by inorganic *** and feldspar develop large and regular pores,resulting in better pore connectivity,whereas clay minerals and calcite with plenty of complex intragranular pores do *** matter negatively influences pore connectivity because the dissolution of calcite by organic acid produced during hydrocarbon generation leads to a more complex and heterogeneous pore *** study sheds light on the pore connectivity and controlling factors of the shale oil reservoir and aids in the understanding of shale oil mobility.

关键词： Pore connectivity Spontaneous imbibition Nuclear magnetic resonance Mercury intrusion capillary pressure Shale oil reservoir

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硫掺杂氧化钨电催化剂的析氢性能研究

陕西科技大学学报 2025年第1期43卷 107-114,125页

作者：贾鹏飞杨军李硕郑璐瑶张煜国陕西科技大学材料科学与工程学院陕西西安710021

通过硫掺杂来改善氧化钨(WO_(3))电催化剂活性不足和反应动力学缓慢的问题.采用二次煅烧法成功合成了硫掺杂氧化钨(S-WO_(3))电催化剂,并系统地研究了掺杂浓度对其形貌、结构和电化学性能的影响.结果表明,硫掺入氧化钨后能够在引入氧缺... 详细信息

通过硫掺杂来改善氧化钨(WO_(3))电催化剂活性不足和反应动力学缓慢的问题.采用二次煅烧法成功合成了硫掺杂氧化钨(S-WO_(3))电催化剂,并系统地研究了掺杂浓度对其形貌、结构和电化学性能的影响.结果表明,硫掺入氧化钨后能够在引入氧缺陷的同时调控电子结构,显著提高了氧化钨的电催化活性.使用硫粉量为0.11 g的S-WO_(3)-1催化剂具有最佳的硫掺杂浓度.为了实现10 mA cm^(-2)的电流密度仅仅需要161 mV过电位,并且能够持续长达30000 s的析氢过程,显示出优异的催化活性和循环稳定性.本研究为开发掺杂型高效析氢电催化剂提供了新途径.

关键词：电催化剂析氢反应氧化钨硫掺杂电子结构

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Evolutionary-assisted reinforcement learning for reservoir real-time production optimization under uncertainty

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Petroleum Science 2023年第1期20卷 261-276页

作者： Zhong-zheng Wang Kai zhang guo-Dong chen jin-Ding zhang Wen-Dong Wang Hao-chen Wang li-Ming zhang Xia Yan jun Yao School of Petroleum Engineering China University of PetroleumQingdao266580ShandongChina Qingdao University of Technology Qingdao266520ShandongChina The University of Hong Kong 999077Hong KongChina

Production optimization has gained increasing attention from the smart oilfield community because it can increase economic benefits and oil recovery *** existing methods could produce high-optimality results,they cannot be applied to real-time optimization for large-scale reservoirs due to high computational *** addition,most methods generally assume that the reservoir model is deterministic and ignore the uncertainty of the subsurface environment,making the obtained scheme unreliable for practical *** this work,an efficient and robust method,namely evolutionaryassisted reinforcement learning(EARL),is proposed to achieve real-time production optimization under ***,the production optimization problem is modeled as a Markov decision process in which a reinforcement learning agent interacts with the reservoir simulator to train a control policy that maximizes the specified *** deal with the problems of brittle convergence properties and lack of efficient exploration strategies of reinforcement learning approaches,a population-based evolutionary algorithm is introduced to assist the training of agents,which provides diverse exploration experiences and promotes stability and robustness due to its inherent *** with prior methods that only optimize a solution for a particular scenario,the proposed approach trains a policy that can adapt to uncertain environments and make real-time decisions to cope with unknown *** trained policy,represented by a deep convolutional neural network,can adaptively adjust the well controls based on different reservoir *** results on two reservoir models show that the proposed approach not only outperforms the RL and EA methods in terms of optimization efficiency but also has strong robustness and real-time decision capacity.

关键词： Production optimization Deep reinforcement learning Evolutionary algorithm Real-time optimization Optimization under uncertainty

Accurate and broadband manipulations of harmonic amplitudes and phases to reach 256 QAM millimeter-wave wireless communications by time-domain digital coding metasurface

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National Science Review 2022年第1期9卷 36-46页

作者： Ming zheng chen Wankai Tang jun Yan Dai jun chen Ke Lei zhang cheng zhang jin Yang lianlin li Qiang cheng Shi jin Tie jun Cui Institute of Electromagnetic Space Southeast University State Key Laboratory of Terahertz and Millimeter Waves City University of Hong Kong State Key Laboratory of Advanced Optical Communication Systems and Networks Department of Electronics Peking University National Mobile Communications Research Laboratory Southeast University State Key Laboratory of Millimeter Waves Southeast University Center of Intelligent Metamaterials Pazhou Laboratory

We propose a theoretical mechanism and new coding strategy to realize extremely accurate manipulations of nonlinear electromagnetic harmonics in ultrawide frequency band based on a time-domain digital coding metasurface(TDCM).Using the proposed mechanism and coding strategy,we design and fabricate a millimeter-wave(mmWave) TDCM,which is composed of reprogrammable meta-atoms embedded with positive-intrinsic-negative *** controlling the duty ratios and time delays of the digital coding sequences loaded on a TDCM,experimental results show that both amplitudes and phases of different harmonics can be engineered at will simultaneously and precisely in broad frequency band from 22 to33 GHz,even when the coding states are imperfect,which is in good agreement with theoretical *** on the fabricated high-performance TDCM,we further propose and experimentally realize a large-capacity mmWave wireless communication system,where 256 quadrature amplitude modulation,along with other schemes,is *** new wireless communication system has a much simpler architecture than the currently used mmWave wireless systems,and hence can significantly reduce the hardware *** believe that the proposed method and system architecture can find vast application in future mmWave and terahertz-wave wireless communication and radar systems.

关键词： metasurface time-domain digital coding accurate and broadband harmonic control 256 QAM millimeter-wave wireless communications

Space-frequency-polarization-division multiplexed wireless communication system using anisotropic space-time-coding digital metasurface

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National Science Review 2022年第11期9卷 149-160页

作者： jun chen Ke Xiangyu chen Wankai Tang Ming zheng chen Lei zhang li Wang jun Yan Dai jin Yang jun Wei zhang lijie Wu Qiang cheng Shi jin Tie jun Cui State Key Laboratory of Millimeter Waves Southeast University Institute of Electromagnetic Space Southeast University Frontiers Science Center for Mobile Information Communication and Security Southeast University National Mobile Communications Research Laboratory Southeast University Southeast University Wuxi Campus

In the past few years, wireless communications based on digital coding metasurfaces have gained research interest owing to their simplified architectures and low cost. However, in most of the metasurface-based wireless systems, a single-polarization scenario is used, limiting the channel capacities. To solve the problem, multiplexing methods have been adopted, but the system complexity is inevitably increased. Here,a space-frequency-polarization-division multiplexed wireless communication system is proposed using an anisotropic space-time-coding digital metasurface. By separately designing time-varying control voltage sequences for differently oriented varactor diodes integrated on the metasurface, we achieve frequency-polarization-division multiplexed modulations. By further introducing different time-delay gradients to the control voltage sequences in two polarization directions, we successfully obtain space-frequency-polarization-division multiplexed modulations to realize a wireless communication system with a new architecture. The new communication system is designed with compact dual-polarized meta-elements, and can improve channel capacity and space utilization. Experimental results demonstrate the high-performance and real-time transmission capability of the proposed communication system,confirming its potential application in multiple-user collaborative wireless communications.

关键词： polarization-division multiplexing frequency-division multiplexing space-division multiplexing space-time coding wireless communication

Wind speed retrieval using GNSS-R technique with geographic partitioning

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Satellite Navigation 2023年第1期4卷 140-154,I0005页

作者： zheng li Fei guo Fade chen Zhiyu zhang Xiaohong zhang School of Geodesy and Geomatics Wuhan UniversityWuhan 430079China

In this paper,the efect of geographical location on Cyclone Global Navigation Satellite System(CYGNSS)observables is demonstrated for the frst *** is found that the observables corresponding to the same wind speed vary with geographic location *** latitude and longitude information is included in the conventional method,it cannot efectively reduce the errors caused by geographic diferences due to the non-monotonic changes of observables with respect to latitude and ***,an improved method for Global Navigation Satellite System Refectometry(GNSS-R)wind speed retrieval that takes geographical diferences into account is *** sea surface is divided into diferent areas for independent wind speed retrieval,and the training set is resampled by considering high wind *** balance between the retrieval accuracies of high and low wind speeds,the results with the random training samples and the resampling samples are *** with the conventional method,in the range of 0–20 m/s,the improved method reduces the Root Mean Square Error(RMSE)of retrieved wind speeds from 1.52 to 1.34 m/s,and enhances the correlation coefcient from 0.86 to 0.90;while in the range of 20–30 m/s,the RMSE decreases from 8.07 to 4.06 m/s,and the correlation coefcient increases from 0.04 to ***,the SNR observations are moderately correlated with marine gravities,showing correlation coefcients of 0.5–0.6,which may provide a useful reference for marine gravity retrieval using GNSS-R in the future.

关键词： CYGNSS Geographical diferences Ocean wind speed GNSS refectometry Marine gravity