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Freestanding strontium vanadate/carbon nanotube films for long-life aqueous zinc-ion batteries

Rare Metals 2022年第2期41卷 415-424页

作者： Ye-Hong Du Xian-yu Liu Xin-yu Wang Jun-Cai Sun qiong-qiong Lu Jian-Zhi Wang Ahmad Omar Daria Mikhailova Institute of Materials and Technology Dalian Maritime UniversityDalian 116026China e-mail:wangxinyu@*** School of Chemistry and Chemical Engineering Lanzhou City UniversityLanzhou 730070China Leibniz Institute for Solid State and Materials Research(IFW)Dresden E.V Helmholtzstraße 2001069 DresdenGermany e-mail:q.lu@ifw-dresden.de Key Laboratory for Green Chemical Process of Ministry of Education School of Chemical Engineering and PharmacyWuhan Institute of TechnologyWuhan 430205China

Aqueous rechargeable zinc-ion battery(ZIB)is considered to be a potential energy storage system for large-scale applications due to its environmental friendliness,high safety,and low ***,it remains challenging to develop suitable cathode materials with high specific capacity and long-term cyclic ***,we have fabricated freestanding Sr0.19V2O51.3H2O/carbon nanotubes(SrVO/CNTs)composite films with different mass ratios by incorporating SrVO into CNTs *** synthesized SrVO possesses a large interlayer spacing of 1.31 nm,which facilitates Zn(2+)***,the SrVO/CNTs composite film with conductive network structure promotes electron transfer and ensures good contact between SrVO and CNTs during the long-term cycling *** a result,the battery based on the SrVO/CNTs composite cathode with a mass ratio of 7:3 delivers a specific capacity of 326 mAh·g^(-1)at 0.1 A·g^(-1)and 145 mAh·g^(-1)at 5 A·g^(-1),demonstrating a high capacity and excellent rate ***,the assembled ZIB shows good capacity retention of 91%even after ultra-long cycling for 7500 cycles at a high current rate of 5 Ag^(-1).More importantly,the battery also delivers a high energy density and power density,as 290 Wh·kg^(-1)at 125 W·kg^(-1)(0.1 A·g^(-1)),or 115 Wh·kg^(-1)at 6078 W·kg^(-1)(5 Ag^(-1)).The results demonstrate that the SrVO/CNTs composite is a promising cathode toward large-scale energy storage applications.

关键词： Aqueous zinc-ion battery Strontium vanadate Carbon nanotubes network Freestanding composite film Long cycle life

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Timing of N Application Affects Net Primary Production of Soybean with Different Planting Densities

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Journal of Integrative Agriculture 2014年第12期13卷 2778-2787页

作者： ZHANG Ming-cong SUN Wen-xiang LIU yuan-ying LUO Sheng-guo ZHAO Jing wu qiong wu Zhen-yu JIANG Yi Resource and Environment College Northeast Agricultural University

Understanding the relationship between the timing of N fertilizer applications and crop primary production is crucial for achieving high yield and N use efifciency in agriculture. This study investigated the effects of starting-N plus topdressing N applications （as compared to the common practice of all basal application） on soybean photosynthetic capacity under different planting densities. A ifeld experiment was conducted in two growing seasons （2011 and 2012）, and the soybean （Glycine max L. Merrill） cultivar was Dongnong 52, three planting densities （20, 25 and 30 plants m-2）, and four N fertilizer application patterns （all N fertilizer of 6 g N m-2 as basal fertilizer, all N fertilizer as topdressing at beginning pod stage （R3）, 1.8 g N m-2 as basal fertilizer and 4.2 g N m-2 as topdressing at stage R3 and full pod stage （R4）, respectively）. The results indicated that under the same planting density, compared to applying all N as basal fertilizer, the application of starter-N plus topdressing N substantially reduced the rate of pod abscission, and enhanced leaf area index （LAI） signiifcantly at beginning seed stage （R5）（P〈0.05）, net assimilation rate （NAR） during stages R4-full seed stage （R6）（P〈0.05）, contribution rate of post-seed iflling assimilate to seed （CPA）（P〈0.05）, and yield （P〈0.05）. Applying topdressing N at stage R4 resulted in higher net primary production and yield than applying topdressing N at stage R3. When applying starter-N plus topdressing N at planting density of 25 plants m-2, LAI after stage R5 and NAR after stage R4 were increased by 5.92-16.3%（P〈0.05） and 13.7-26.6%（P〈0.05） with the planting density of 20 plants m-2, respectively, and yield was 8.46-14.0%（P〈0.05） higher than that under 20 plants m-2. When planting density increased to 30 plants m-2, only LAI during stages R4-R5 and NAR during stages R4-R5 increased by applying starter-N plus topdressing N, while the other indexes declined. Overall, results of this study demonstrated

关键词： soybean starter-N plus topdressing N density leaf area index (LAI) net assimilation rate (NAR)

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Changes in the patterns of inorganic nitrogen and TN/TP ratio and the associated mechanism of biological regulation in the shallow lakes of the middle and lower reaches of the Yangtze River

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Science China Earth Sciences 2006年第z1期49卷 126-134页

作者： wu Shikai XIE Ping WANG Songbo ZHOU qiong Donghu Experimental Station of Lake Ecosystems State Key Laboratory of Freshwater Ecology and Biotechnology of ChinaInstitute of Hydrobiology Chinese Academy of Sciences Wuhan 430072 China Donghu Experimental Station of Lake Ecosystems State Key Laboratory of Freshwater Ecology and Biotechnology of ChinaInstitute of Hydrobiology Chinese Academy of Sciences Wuhan 430072 China Donghu Experimental Station of Lake Ecosystems State Key Laboratory of Freshwater Ecology and Biotechnology of ChinaInstitute of Hydrobiology Chinese Academy of Sciences Wuhan 430072 China Donghu Experimental Station of Lake Ecosystems State Key Laboratory of Freshwater Ecology and Biotechnology of ChinaInstitute of Hydrobiology Chinese Academy of Sciences Wuhan 430072 China

The changes of NH3-N, NO3-N, NO2-N and TN/TP were studied during growth and non-growth season in 33 subtropical shallow lakes in the middle and lower reaches of the Yangtze River. There were significant positive correlations among all nutrient concentrations, and the correlations were better in growth season than in non-growth season. When TP＞0.1 mgL-1, NH3-N increased sharply in non-growth season with increasing TP, and NO3-N increased in growth season but decreased in non-growth season with TP. These might be attributed to lower dissolved oxygen and low temperature in non-growth season of the hypereutrophic lakes, since nitrification is more sensitive to dissolved oxygen and temperature than antinitrification. When 0.1 mgL-1＞TP＞0.035 mgL-1, TN and all kinds of inorganic nitrogen were lower in growth season than in non-growth season, and phytoplankton might be the vital regulating factor. When TP＜0.035 mgL-1, inorganic nitrogen concentrations were relatively low and NH3-N, NO2-N had significant correlations with phytoplankton, indicating that NH3-N and NO2-N might be limiting factors to phytoplankton. In addition, TN/TP went down with decline in TP concentration, and TN and inorganic nitrogen concentrations were obviously lower in growth season than in non-growth season, suggesting that decreasing nitrogen (especially NH3-N and NO3-N) was an important reason for the decreasing TN/TP in growth season. The ranges of TN/TP were closely related to trophic level in both growth and non-growth seasons, and it is apparent that in the eutrophic and hypertrophic state the TN/TP ratio was obviously lower in growth season than in non-growth season. The changes of the TN/TP ratio were closely correlated with trophic levels, and both declines of TN in the water column and TP release from the sediment were important factors for the decline of the TN/TP ratio in growth season.

关键词： nitrate-nitrogen, ammonium-nitrogen, nitrite-nitrogen, shallow lakes, phytoplankton.

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Time allocation scheme in IEEE 802.15.3 TDMA mechanism

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2006年第z1期7卷 159-164页

作者： LIU Xin DAI qiong-hai wu Qiu-feng Department of Automation Tsinghua University Beijing 100084 China Department of Automation Tsinghua University Beijing 100084 China Department of Automation Tsinghua University Beijing 100084 China

In network with a shared channel in TDMA mechanism, it is a core issue to effectively allocate channel time to provide service guarantees for flows with QoS requirements. This paper proposes a simple and efficient time allocation scheme called MES-ESRPT (MCTA at the End of Superframe-Enhanced Shortest Remaining Processing Time) for delay-sensitive VBR traffic in accordance with IEEE 802.15.3 standard. In this algorithm, PNC (piconet coordinator) allocates one MCTA (Management Channel Time Allocation) for each stream which is the process of communication at the end of superframe. During the MCTA period, each transmitter should report current fragments number of the first MSDU (MAC Service Data Unit) and the fragments number of the remainder MSDUs to PNC. In the next superframe, PNC firstly allocates part CTAs (Channel Time Allocation) for each stream based on the remainder fragments number of the first MSDU by SRPT rule, then allocates remainder CTAs for each stream based on all fragments number of remainder MSDUs by the same SRPT rule. Simulation results showed that our proposed MES-ESRPT method achieves significantly better performance in QoS for multimedia streams compared to the existing schemes.

关键词： Shortest remaining processing time (SRPT), MAC layer, TDMA, Quality of Service (QoS)

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Study of caffeine binding to human serum albumin using optical spectroscopic methods

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Science China Chemistry 2009年第12期52卷 2205-2212页

作者： wu qiong LI ChaoHong HU YanJun LIU Yi College of Chemistry&Chemical Engineering Hubei UniversityWuhan 430062China State Key Laboratory of Virology&College of Chemistry and Molecular Sciences Wuhan UniversityWuhan 430072China Key Laboratory for Oral Biomedical Engineering of MOE&School of Stomatology Wuhan UniversityWuhan 430072China

The binding of caffeine to human serum albumin (HSA) under physiological conditions has been stud-ied by the methods of fluorescence,UV-vis absorbance and circular dichroism (CD) spectroscopy. The mechanism of quenching of HSA fluorescence by caffeine was shown to involve a dynamic quenching procedure. The number of binding sites n and apparent binding constant Kb were measured by the fluorescence quenching method and the thermodynamic parameters △H,△G,△S were calculated. The results indicate that the binding is mainly enthalpy-driven,with van der Waals interactions and hydrogen bonding playing major roles in the reaction. The distance r between donor (HSA) and acceptor (caffeine) was obtained according to the Frster theory of non-radiative energy transfer. Synchronous fluorescence,CD and three-dimensional fluorescence spectroscopy showed that the microenvironment and conformation of HSA were altered during the reaction.

关键词： caffeine human serum albumin fluorescence quenching circular dichroism (CD) spectroscopy UV-vis spectroscopy.

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A Comprehensive Survey on Joint Resource Allocation Strategies in Federated Edge Learning

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Computers, Materials & Continua 2024年第11期81卷 1953-1998页

作者： Jingbo Zhang qiong wu Pingyi Fan Qiang Fan School of Internet of Things Engineering Jiangnan UniversityWuxi214122China Department of Electronic Engineering Beijing National Research Center for Information Science and TechnologyTsinghua UniversityBeijing100084China Qualcomm San JoseCA 95110USA

Federated Edge Learning(FEL),an emerging distributed Machine Learning(ML)paradigm,enables model training in a distributed environment while ensuring user privacy by using physical separation for each user’s ***,with the development of complex application scenarios such as the Internet of Things(IoT)and Smart Earth,the conventional resource allocation schemes can no longer effectively support these growing computational and communication ***,joint resource optimization may be the key solution to the scaling *** paper simultaneously addresses the multifaceted challenges of computation and communication,with the growing multiple resource *** systematically review the joint allocation strategies for different resources(computation,data,communication,and network topology)in FEL,and summarize the advantages in improving system efficiency,reducing latency,enhancing resource utilization,and enhancing *** addition,we present the potential ability of joint optimization to enhance privacy preservation by reducing communication requirements,*** work not only provides theoretical support for resource management in federated learning(FL)systems,but also provides ideas for potential optimal deployment in multiple real-world *** thoroughly discussing the current challenges and future research directions,it also provides some important insights into multi-resource optimization in complex application environments.

关键词： Federated edge learning resource allocation communication resource computing resource network topology

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Theoretical design of new bridge-ring insensitive high energy compounds by selected normal Diels-Alder reactions between NH_(2)-substituted oxazoles and NO_(2)/NF_(2)/NHNO_(2)-substituted ethylenes/acetylenes

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Defence Technology（防务技术） 2021年第5期17卷 1731-1739页

作者： qiong wu Qin-nan Hu Ming-quan Li Ze-wu Zhang Wei-hua Zhu Jiangsu Key Laboratory of Advanced Structural Materials and Application Technology School of Materials Science and EngineeringNanjing Institute of Technology1 Hongjing RoadNanjing211167China Institute for Computation in Molecular and Materials Science and Department of Chemistry Nanjing University of Science and TechnologyNanjing210094China

In this work,NH_(2)-substituted oxazoles and NO_(2)/NF_(2)/NHNO_(2)-substituted ethylenes/acetylenes were designed and used as dienes and dienophiles,respectively,in order to develop new bridge-ring insensitive high energy compounds through the Diels-Alder reaction between *** reaction type,reaction feasibility and performance of reaction products were investigated in detail *** results showed that dienes most possibly react with dienophiles through the HOMO-diene controlled normal Diels-Alder reaction at relatively low energy *** could react with the designed dienes much more easily than other dienophiles,and was employed to further design 29 new bridge-ring energetic *** to high heat of formation,density and oxygen balance,all designed bridge-ring energetic compounds have outstanding detonation performance,16 of them have higher energy than HMX(1,3,5,7-tetranitro-1,3,5,7-tetrazocine)and 2 others even possess comparative energy with the representative of high energy compounds CL-20(2,4,6,8,10,12-hexanitro-2,4,6,8,10,12-hexaazaisowurtzitane).The predicted average h50 value of these bridge-ring energetic compounds is 83 cm,showing their low impact *** NH2 groups could obviously impel the proceeding of Diels-Alder reactions,but would slightly decrease the energy and sensitivity *** all,the new designed bridge-ring compounds have both high energy and low sensitivity,and may be produced through Diels-Alder reactions at relatively low energy *** paper may be helpful for the theoretical design and experiment synthesis of new advanced insensitive high energy compounds.

关键词： Diels-Alder Energetic compounds Oxazole High energy Insensitive

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Blind image deconvolution for single motion-blurred image

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The Journal of China Universities of Posts and Telecommunications 2010年第3期17卷 104-109页

作者： SUN Shao-jie wu qiong Li Guo-hui College of Information System and Management National University of Defense Technology Changsha 410073 China Airforce Training Equipment Institute Beijing 100195 China

Motion blur due to camera shake during exposure is one of the most common reasons of image degradation, which usually reduces the quality of photographs seriously. Based on the statistical properties of the natural image＇s gradient and the blur kernel, a blind deconvolution algorithm is proposed to restore the motion-blurred image caused by camera shake, adopting the variational Bayesian estimation theory. In addition, the ring effect is one problem that is not avoided in the process of image deconvolution, and usually makes the visual effect of the restored image badly. So a dering method is put forward based on the sub-region detection and fuzzy filter. Tested on the real blurred photographs, the experimental results show that the proposed algorithm of blind image deconvolution can remove the camera-shake motion blur from the degraded image effectively, and can eliminate the ring effect better, while preserve the edges and details of the image well.

关键词： blind image deconvolution motion blur camera shake ring effect

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Switching Control System Based on Robust Model Reference Adaptive Control

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Journal of Systems Science & Complexity 2016年第4期29卷 897-932页

作者： HU qiong FEI Qing MA Hongbin wu Qinghe GENG Qingbo School of Automation Beijing Institute of Technology Shanghai Institute of Optics and Fine Mechanics Chinese Academy of Sciences State Key Laboratory of Intelligent Control and Decision of Complex Systems Beijing Institution of Technology

For conventional adaptive control, time-varying parametric uncertainty and unmodeled dynamics are ticklish problems, which will lead to undesirable performance or even instability and nonrobust behavior, respectively. In this study, a class of discrete-time switched systems with unmodeled dynamics is taken into consideration. Moreover, nonlinear systems are here supposed to be approximated with the class of switched systems considered in this paper, and thereby switching control design is investigated for both switched systems and nonlinear systems to assure stability and performance. For robustness against unmodeled dynamics and uncertainty, robust model reference adaptive control(RMRAC) law is developed as the basis of controller design for each individual subsystem in the switched systems or nonlinear systems. Meanwhile, two different switching laws are presented for switched systems and nonlinear systems, respectively. Thereby, the authors incorporate the corresponding switching law into the RMRAC law to construct two schemes of switching control respectively for the two kinds of controlled systems. Both closed-loop analyses and simulation examples are provided to illustrate the validity of the two proposed switching control schemes. Furthermore, as to the proposed scheme for nonlinear systems, its potential for practical application is demonstrated through simulations of longitudinal control for F-16 aircraft.

关键词： Longitudinal control of F-16 aircraft switching control switching law. nonlinear systems RMRAC switched systems

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How do temporal and spectral features .matter in crop classification in Heilongjiang Province, China？

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Journal of Integrative Agriculture 2017年第2期16卷 324-336页

作者： HU qiong wu Wen-bin SONG Qian LU Miao CHEN Di yu Qiang-yi TANG Hua-jun Key Laboratory of Agri-informatics Ministry of Agriculture/Institute of Agricultural Resources and Regional Planning Chinese Academy of Agricultural Sciences Beijing 100081 P.R.China Remote Sensing Technology Center Heilongjiang Academy of Agricultural Sciences Harbin 150086 PR. China

How to fully use spectral and temporal information for efficient identification of crops becomes a crucial issue since each crop has its specific seasonal dynamics. A thorough understanding on the relative usefulness of spectral and temporal features is thus essential for better organization of crop classification information. This study, taking Heilongjiang Province as the study area, aims to use time-series moderate resolution imaging spectroradiometer （MODIS） surface reflectance product （MOD09A1） data to evaluate the importance of spectral and temporal features for crop classification. In doing so, a feature selection strategy based on separability index （SI） was first used to rank the most important spectro-temporal features for crop classification. Ten feature scenarios with different spectral and temporal variable combinations were then devised, which were used for crop classification using the support vector machine and their accuracies were finally assessed with the same crop samples. The results show that the normalized difference tillage index （NDTI）, land surface water index （LSWl） and enhanced vegetation index （EVI） are the most informative spectral features and late August to early September is the most informative temporal window for identifying crops in Heilongjiang for the observed year 2011. Spectral diversity and time variety are both vital for crop classification, and their combined use can improve the accuracy by about 30% in comparison with single image. The feature selection technique based on SI analysis is superior for achieving high crop classification accuracy （producers＇ accuracy of 94.03% and users＇ accuracy of 93.77%） with a small number of features. Increasing temporal resolution is not necessarily important for improving the classification accuracies for crops, and a relatively high classification accuracy can be achieved as long as the images associated with key phenological phrases are retained.

关键词： crop identification temporal feature spectral feature feature selection MODIS

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