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Highly efficient catalyzed by imidazolium-based dual-sulfonic acid functionalized ionic liquids for liquid phase Beckmann rearran{1.ment:experiments and COSMO-RS calculations

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Green Chemical engineering 2024年第1期5卷 108-118页

作者： Xin Guo zhiyuan Wang Ye {1. Jiahui Zhang Yanduo liu zhiyuan Mu Siqi Jiang Chunxiao Ren Dan lv Yufeng Hu Zhichang liu State Key Laboratory of Heavy Oil Processing and High Pressure Fluid Phase Behavior&Property Research Laboratory China University of PetroleumBeijing102249China School of Chemistry and Materials Science University of Science and Technology of ChinaHefei230026China School of Light Industry and engineering South China University of TechnologyGuangzhou510641China

A production technique with the high yield and environmentally friendly process need be developed forε-Caprolactam(CPL)in the chemical *** technology is highly desired to design and synthesize high--performance catalysts for liquid phase Beckmann rearrangement of cyclohexanone oxime(CHO)to *** this work,3-methyl-1.(propyl-4-sulfonyl)imidazo{1.m methanesulfonate([PHSO_(3)MIM][MSA])with highly efficient and excellent yield is synthesized *** the optimum molar ratio of ZnCl_(2)over[PHSO_(3)MIM][MSA]was 0.02,it exhibits the high selectivity(94%)of CPL at 90℃for 1.***,Fourier-transform infrared(FT-IR)investigations show that the functional Br∅nsted-Lewis acidic types of ionic liquids(ILs)are formed by the uniformly distributed ZnCl_(2)and[PHSO_(3)MIM][MSA].In addition,the hydrogen bond(H-bond)is formed between CHO and *** ten reaction cycles,no significant structure changes are observed in the recovered[PHSO_(3)MIM][MSA]-ZnCl_(2).The solubilities of ILs are predicted by using COSMO-RS model,the results show that[PHSO_(3)MIM][MSA]is a promising candidate for the liquid phase Beckmann rearrangement of CHO into ***,a theoretical model of the H-bond interactions between ILs and CHO is further confirmed to support the advance of reaction mechanism.A feasible way is provided for the CPL production technique in the liquid phase Beckmann rearrangement reaction.

关键词： Liquid phase Beckmann rearrangement Imidazolium-based ionic liquids COSMO-RS calculations H-bond

Unraveling high efficiency multi-step sodium storage and bidirectional redox kinetics synergy mechanism of cobalt-doping vanadium disulfide anode

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Journal of Energy Chemistry 2024年第7期94卷 148-157页

作者： Enzhi Li Mingshan Wang Yuanlong Feng Lin yang Qian Li Zhenliang yang Junchen Chen Bo Yu Bingshu Guo zhiyuan Ma Yun Huang Jiangtao liu Xing Li School of New Energy and Materials Southwest Petroleum UniversityChengdu 610500SichuanChina Institute of Materials China Academy of Engineering PhysicsMianyang 621908SichuanChina State Key Laboratory of Advanced Chemical power Sources Guizhou Meiling Power Sources Co.Ltd.Zunyi 563003GuizhouChina school of Chemistry and Chemical engineering Harbin Institute of TechnologyHarbin 150001HeilongjiangChina

Sodium-based storage devices based on conversion-type metal sulfide anodes have attracted great atten-tion due to their multivalent ion redox reaction ***,they also suffer from sodium polysul-fides(NaPSs)shuttling problems during the sluggish Na^(+) redox process,leading to"voltage failure"and rapid capacity ***,a metal cobalt-doping vanadium disulfide(Co-VS_(2))is proposed to simulta-neously accelerate the electrochemical reaction of VS_(2) and enhance the bidirectional redox of soluble *** is found that the strong adsorption of NaPSs by V-Co alloy nanoparticles formed in situ during the conversion reaction of Co-VS_(2) can effectively inhibit the dissolution and shuttle of NaPSs,and ther-modynamically reduce the formation energy barrier of the reaction path to effectively drive the complete conversion reaction,while the metal transition of Co elements enhances reconversion kinetics to achieve high ***,Co-VS_(2) also produce abundant sulfur vacancies and unsaturated sulfur edge defects,significantly improve ionic/electron diffusion ***,the Co-VS_(2) anode exhibits ultrahigh rate capability(562 mA h g^(-1. at 5 A g^(-1.),high initial coulombic efficiency(~90%)and 1.,000 ultralong cycle life with capacity retention of 90%in sodium-ion batteries(SIBs),as well as impressive energy/power density(1.8 Wh kg^(-1./31.250 W kg^(-1.)and over 1..000 stable cycles in sodium-ion hybrid capacitors(SIHCs).Moreover,the pouch cell-type SIHC displays a high-energy density of 1.2 Wh kg^(-1. and exceed 600 stable *** work deepens the understanding of the electrochemical reaction mechanism of conversion-type metal sulfide anodes and provides a valuable solution to the shuttlingofNaPSs inSIBsandSIHCs.

关键词： Sodium-ionbatteries Sodium-ion hybrid capacitors Pouch cells Vanadium disulfide Shuttle effect

An aqueous rechargeable Fe//LiMn_(2)O_()hybrid battery with superior electrochemical performance beyond mainstream Fe-based batteries

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Nano Research 2024年第6期17卷 5168-5178页

作者： Yu liu Dehui Xie Yuxin Shi Rongguan {1. Yingna Chang Yuzhen Sun zhiyuan Zhao Jindi Wang Kefan Song Huayu Wu Tuan K.A.Hoang Rong Xing Huan Pang Institute of New Energy on Chemical Storage and {1. Sources School of Chemical and Environmental EngineeringYancheng Teachers UniversityYancheng 224000China School of Chemistry and Chemical engineering Yangzhou UniversityYangzhou 225009China department of Chemical {1. University of Waterloo200 University Avenue WestWaterlooOntario N2L 3G1Canada

Aqueous rechargeable batteries(ARBs)are generally safer than non-aqueous analogues,they are also less-expensive,and more friendly to the ***,the inherent disadvantage of the narrow electrochemical window of H2O seriously restricts the energy density and output voltage of ARBs,especially aqueous rechargeable Fe-based ***,we introduce a new battery system:the anode contains C@Fe/Fe_(2)O_(3)composite,which is interfaced with an alkaline electrolyte;the cathode contains LiMn_(2)O_()in contact with a neutral electrolyte.A Li^(+)-conducting membrane is carefully selected to decouple the electrode-electrolyte,which effectively widens the electrochemical window to above 2.65 V,thereby enables an aqueous rechargeable iron *** average output voltage is 1.83 V and its energy density is 235.3 Wh/kg at 549 W/*** this work,we propose the energy storage mechanism with the aid of density functional theory(DFT).The calculated reduction potential of the anode agrees with the experimental ***,this battery system demonstrates long cycle lifespan of approximately 2500 cycles at 2 A/g,corresponding to a capacity retention of 82.1..These results are very far superior than those of mainstream aqueous rechargeable Fe-based batteries,which guarantee future investigation for storing electricity energy.

关键词： aqueous battery high voltage high energy iron oxide theoretical calculation

Investigation into epitaxial growth optimization of a novel AlGaN/GaN HEMT structure for application in UV photodetectors

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Science china Materials 2024年第9期67卷 2828-2837页

作者： zhiyuan {1. Wanglong Wu Xiong yang Menglong Zhang Lixiang Han Jianpeng Lei Quansheng Zheng Nengjie Huo Xiaozhou Wang Jingbo Li School of Semiconductor Science and Technology Guangdong Provincial Key Laboratory of Chip and Integration TechnologySouth China Normal UniversityFoshan528225China College of Optical Science and {1. Zhejiang UniversityHangzhou310027China Zhejiang Xinke Semiconductor Co. Ltd.Hangzhou311400China Jiangxi engineering Laboratory for Optoelectronics Testing Technology Nanchang Hangkong UniversityNanchang330063China department of Applied Physics School of Physics and ElectronicsHunan UniversityChangsha410082China

In this work,a novel ultraviolet(UV)photodetector(PD)based on AlGaN/u-GaN/p-GaN/u-GaN heterojunction high electron mobility transistor(HEMT)has been *** HEMT epilayer is grown using the metal-organic chemical vapor deposition(MOCVD)technique,and the growth parameters,including the AlGaN growth temperature,preheating temperature of the p-GaN layer,and NH3/N2 flow rate,are optimized to improve the quality of the *** optimized epilayer exhibits a flat surface with a root mean square value of 0.1.6 nm and low dislocation *** p-GaN thickness in epitaxial wafers has a significant influence on electrical and UV *** a p-GaN of 1.m,the UV PD demonstrates a significant switching ratio and transconductance of 1.7 and 1.7.3 mS mm^(-1.,*** as a UV PD,it also exhibits a high light on/off ratio(I_(light)/I_(dark))of 6.35×1.^(5),a high responsivity(R)of 48.1. A W^(-1.,and a detectivity(D*)of 6.85×1.^(1.)Jones under 365-nm UV illumination with light power density of 86.972 mW cm^(-2).The high-performance HEMT and UV detectors,which incorporate p-GaN etchless technology,have been refined through advancements in epitaxial growth and structural *** improvements solidify the groundwork for lar{1.-scale manufacturing of UV communication systems and laser diodes.

关键词： AlGaN/GaN-based HEMT epitaxial growth by MOCVD p-GaN/u-GaN junction UV photodetector

Highly Thermally Conductive and Structurally Ultra‑Stable Graphitic Films with Seamless Heterointerfaces for Extreme Thermal Management

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Nano-Micro Letters 2024年第3期16卷 383-397页

作者： Peijuan Zhang Yuanyuan Hao Hang Shi Jiahao Lu Yingjun liu Xin Ming Ya Wang Wenzhang Fang Yuxing Xia Yance Chen Peng Li Ziqiu Wang Qingyun Su Weidong {1. Ji Zhou Ying Zhang Haiwen Lai Weiwei Gao Zhen Xu Chao Gao MOE Key Laboratory of Macromolecular Synthesis and Functionalization Department of Polymer Science and EngineeringKey Laboratory of Adsorption and Separation Materials and Technologies of Zhejiang ProvinceZhejiang University38 Zheda RoadHangzhou 310027People’s Republic of China Shanxi-Zheda Institute of Advanced Materials and Chemical engineering Taiyuan 030032People’s Republic of China Beijing Spacecrafts Manufacturing Co. LtdBeijing Friendship Road 104Haidian DistrictBeijing 100094People’s Republic of China Beijing Institute of Space Mechanics and Electricity Beijing Friendship Road 104Haidian DistrictBeijing 100094People’s Republic of China china Academy of Aerospace Aerodynamics Beijing 100074People’s Republic of China Hangzhou Gaoxi Technol Co. LtdHangzhou 311113People’s Republic of China International Research Center for X Polymers International CampusZhejiang UniversityHaining 314400People’s Republic of China

Highly thermally conductive graphitic film(GF)materials have become a competitive solution for the thermal management of high-{1. electronic ***,their catastrophic structural failure under extreme alternating thermal/cold shock poses a significant challenge to reliability and ***,we present the first investigation into the structural failure mechanism of GF during cyclic liquid nitrogen shocks(LNS),which reveals a bubbling process characterized by“permeation-diffusion-deformation”*** overcome this long-standing structural weakness,a novel metal-nanoarmor strategy is proposed to construct a Cu-modified graphitic film(GF@Cu)with seamless *** well-designed interface ensures superior structural stability for GF@Cu after hundreds of LNS cycles from 77 to 300 ***,GF@Cu maintains high thermal conductivity up to 1.88 W m^(−1.K^(−1.with degradation of less than 5%even after 1.0 LNS cycles,superior to that of pure GF(50%degradation).Our work not only offers an opportunity to improve the robustness of graphitic films by the rational structural design but also facilitates the applications of thermally conductive carbon-based materials for future extreme thermal management in complex aerospace electronics.

关键词： Highly thermally conductive Structurally ultra-stable Graphitic film Extreme thermal management Liquid nitrogen bubbling

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S波段高效GaN逆E类功率放大器

微波学报 2011年第4期27卷 49-52,56页

作者：曹韬刘友江曾荣吕立明中国工程物理研究院电子工程研究所绵阳621900 清华大学工程物理系北京100084

介绍一种高效逆E类功率放大器的设计方法,并选用GaN器件设计了工作于2.3GHz的逆E类功率放大器。当供电26V,输入功率26dBm时,放大器输出功率40.2dBm,工作效率76.1.,PAE为73.3%。提供了详尽的仿真与实测数据并对放大器性能进行分析。用数... 详细信息

介绍一种高效逆E类功率放大器的设计方法,并选用GaN器件设计了工作于2.3GHz的逆E类功率放大器。当供电26V,输入功率26dBm时,放大器输出功率40.2dBm,工作效率76.1.,PAE为73.3%。提供了详尽的仿真与实测数据并对放大器性能进行分析。用数字预失真技术对逆E类功率放大器进行线性化校正并取得了良好的效果。

关键词： E类功率放大器高效率 GaN 数字预失真

Researches Progress on Complexity Drivers of Soil and Water Resources Utilization Structure

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Researches Progress on Complexity Drivers of Soil and Water ...

Keep Healthcare Workers Safe:Application of Teleoperated Robot in Isolation Ward for COVID‑1. Prevention and Control

寒区冰情与冻土水文效应——第4届“寒区水资源及其可持续利用”学术研讨会

作者： Feifei ZHAO~1.Dong liu~2,Ping {1.~3 1.School of Water Conservancy & Civil engineering,Harbin Heilongjiang,1.0030,china 2 Postdoctoral Scientific Research Mobile Station of Agriculture and Forestry Economic Management, Northeast Agricultural university,Harbin Heilongjiang,1.0030,china 3 School of Water Conservancy & Civil engineering,Harbin Heilongjiang,1.0030,china

Soil and water resources utilization structure change caused by global changes is the starting point of soil and water resources *** difficulty in soil and water resources utilization structure study is driving mechanism *** influences of water and soil resources utilization structure were caused by driving *** the real motivation behind the soil and water use change and their interacting mechanism is helpful to improve the comprehensive utilization efficiency of soil and water resources,ease sharp contradictions of oil and water resources utilization,and promote sustainable society development. How to organically combine two systems of water and soil resource,discriminate driving factors in particular space-time scale level,and analyze main driving forces of water and soil resources utilization structure change,sum up driving mechanism of complex systems on water and soil resources utilization structure, which are research emphasis in the *** is potential power to identify soil and water resources utilization structure,find out reasons for soil and water resources utilization structure *** on the review and summarize about driving factors identification and the methods of driving mechanism,this article analyzes the existing problems in the current studies,and proposes the developing trend of soil and water resources utilization structure change study.

关键词： soil and water resources utilization structure complexity driving mechanism research progress

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Chinese Journal of Mechanical engineering 2020年第3期33卷 1-4页

作者： geng {1. Honghao lv Zhiyu Zhang liu {1. Jia Deng Siqi You Juan Du Huayong {1. State Key Laboratory of Fluid power and Mechatronic Systems School of Mechanical EngineeringZhejiang UniversityHangzhou 310027China department of Gastroenterology First Affiliated Hospital of Zhejiang University School of MedicineHangzhou 310003China.

At the time of writing,the coronavirus disease(COVID-1.)has affected 21. countries and territories across the *** to the world health organization(WHO),a total number of 4,735,622 confirmed cases,including 31.,289 deaths was reported[1..In the fight against COVID-1.,nurses,doctors,and other healthcare workers are in the front line of the battle bearing the higher risk of infection[2].The International Council of Nurses(ICN)gathered further information to suggest that more than 90,000 healthcare workers have been infected worldwide[3].Personal protective equipment(PPE)shortage is one of the key factors increasing the infection risk for the medical ***,finding alternative ways to lower the infection risk has become an urgent problem to be solved.

关键词： Robot COV nurse

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Frontiers of Information Technology & Electronic engineering 2017年第6期18卷 796-807页

作者： Zhen-hua YUAN Chen CHEN Xiang CHENG Guo-cheng lv {1.-qing yang Ye JIN State Key Laboratory of Advanced Optical Communication Systems and Networks Peking University department of Electrical & Computer {1. Colorado State University

This article is focused on secure relay beamformer design with a correlated channel model in the relay-eavesdropper network. In this network, a single-antenna source-destination pair transmits secure information with the help of an amplify-and-forward (AF) relay equipped with multiple antennas, and the legitimate and eavesdropping channels are correlated. The relay cannot obtain the instantaneous channel state information (CSI) of the eavesdropper, and has only the knowledge of correlation information between the legitimate and eavesdropping channels. Depending on this information, we derive the conditional distribution of the eavesdropping channel. Two beamformers at the relay are studied for the approximate ergodic secrecy rate:(1. the generalized match-andforward (GMF) beamformer to maximize the legitimate channel rate, and (2) the general-rank beamformer (GRBF).In addition, one lower-bound-maximizing (LBM) beamformer at the relay is discussed for maximizing the lower bound of the ergodic secrecy rate. We find that the GMF beamformer is the optimal rank-one beamformer, that the GRBF is the iteratively optimal beamformer, and that the performance of the LBM beamformer for the ergodic secrecy rate gets close to that of the GRBF for the approximate secrecy rate. It can also be observed that when the relay has lower power or the channel gain of the second hop is low, the performance of the GMF beamformer surpasses that of the GRBF. Numerical results are presented to illustrate the beamformers' performance.

关键词： Physical layer security Relay beamforming Correlated channels Ergodic secrecy rate