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Electrochemical deposition of aluminum on W electrode from AlCl_3-NaCl melts

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中国有色金属学会会刊：英文版 2010年第1期20卷 158-164页

作者：阚洪敏王兆文王晓阳张宁 key laboratory of Advanced Materials Preparation Technology of liaoning province Shenyang University School of Materials and Metallurgy North eastern University

Electrochemical deposition of aluminum on W electrode from AlCl3-NaCl melts was studied by cyclic voltammetry and chronopotentiometry. The results show that Al ( Ⅲ) is reduced in two consecutive steps, i.e., 4Al2Cl7-+3e-→Al+7AlCl4- and then AlCl4-+3e-→Al+4Cl-. The electrochemical reaction of 4Al2Cl7-+3e-→Al+7AlCl4- is reversible. Certain nucleation overpotential is required during the deposition of aluminum on W electrode. Chronopotentiometry analysis also shows that Al (Ⅲ ) is reduced in two consecutive steps under certain current density, which is in reasonable agreement with cyclic voltammograms. By using constant current deposition, the electrodeposits on Al substrate obtained at between 50 and 100 mA/cm2 are quite dense and well adherent to the Al substrate. The electrochemical deposition of aluminum on Cu substrate in AlCl3-NaCl melts indicates that the intermetallic compounds are formed. The intermetallic compounds are AlCu and Al2Cu.

关键词：电化学沉积三氯化铝氯化钠铝电极融化金属间化合物计时电位法循环伏安法

Microwave Absorption of Crystalline Fe/MnO@C Nanocapsules Embedded in Amorphous Carbon

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Nano-Micro Letters 2020年第4期12卷 152-167页

作者： Gaihua He Yuping Duan Huifang Pang key laboratory of Solidification Control and Digital Preparation Technology (liaoning province) School of Materials Science and Engineering Dalian University of Technology

Crystalline Fe/MnO@C core–shell nanocapsules inlaid in porous amorphous carbon matrix(FMCA)was synthesized successfully with a novel confinement *** heterogeneous Fe/MnO nanocrystals are with approximate single-domain size which gives rise to natural resonance in 2–18 *** addition of MnO2 confines degree of graphitization catalyzed by iron and contributes to the formation of amorphous *** heterogeneous materials composed of crystalline–amorphous structures disperse evenly and its density is significantly reduced on account of porous ***,adjustable dielectric loss is achieved by interrupting Fe core aggregation and stacking graphene conductive *** dielectric loss synergistically with magnetic loss endows the FMCA enhanced *** optimal reflection loss(RL)is up to−45 dB,and the effective bandwidth(RL<−10 dB)is 5.0 GHz with 2.0 mm *** proposed confinement strategy not only lays the foundation for designing high-performance microwave absorber,but also offers a general duty synthesis method for heterogeneous crystalline–amorphous composites with tunable composition in other fields.

关键词： Crystalline nanocapsule Amorphous carbon Core–shell structure Interfacial polarization Microwave absorption

Social experience promotes the exploratory behaviour in Java Sparrows

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Avian Research 2023年第1期14卷 33-37页

作者： Qiuyang Chen Guang Chen Mengyao Shao Yuanxiu Wu Jiayu Wang Dongmei Wan Jiangxia Yin The key laboratory of Animal Resource and Epidemic Disease Prevention in liaoning province School of Life SciencesLiaoning UniversityShenyang110036China

Personality widely exists in diverse animal *** inter-individual variance in behaviour is supposed to be influenced by social ***,it remains unknown whether the experience of social life has any carryover effects on the subsequent expression of ***,we examined exploratory behaviour in caged Java Sparrows(Lonchura oryzivora)using exploration *** were assigned to live in either a solitary or a social context for four *** compared the expressions of exploration before and after the treatments,and found that birds showed higher exploration tendencies after than before social life,while the isolated birds were consistent in their exploratory *** living experience led to differences in the exploration activities for birds without significant differences in exploration *** results indicate that social experience can make birds more proactive.

关键词： Animal behaviour Animal personality Exploratory behaviour Lonchura oryztivora Social experience

Climate change characteristics of Amur River

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Water Science and Engineering 2013年第2期6卷 131-144页

作者： Lan-lan YU Zi-qiang XIA Jing-ku LI Tao CAI River Basin Authority of liaoning province State key laboratory of Hydrology-Water Resources and Hydraulic Engineering Institute of International Rivers Research Academy Hohai University Hydrological Bureau of liaoning province

Unusually severe weather is occurring more frequently due to global climate change. Heat waves, rainstorms, snowstorms, and droughts are becoming increasingly common all over the world, threatening human lives and property. Both temperature and precipitation are representative variables usually used to directly reflect and forecast the influences of climate change. In this study, daily data （from 1953 to 1995） and monthly data （from 1950 to 2010） of temperature and precipitation in five regions of the Amur River were examined. The significance of changes in temperature and precipitation was tested using the Mann-Kendall test method. The amplitudes were computed using the linear least-squares regression model, and the extreme temperature and precipitation were analyzed using hydrological statistical methods. The results show the following： the mean annual temperature increased significantly from 1950 to 2010 in the five regions, mainly due to the warming in spring and winter; the annual precipitation changed significantly from 1950 to 2010 only in the lower mainstream of the Amur River; the frequency of extremely low temperature events decreased from 1953 to 1995 in the mainstream of the Amur River; the frequency of high temperature events increased from 1953 to 1995 in the mainstream of the Amur River; and the frequency of extreme precipitation events did not change significantly from 1953 to 1995 in the mainstream of the Amur River. This study provides a valuable theoretical basis for settling disputes between China and Russia on sustainable development and utilization of water resources of the Amur River.

关键词： climate change temperature precipitation extreme weather events Mann-Kendall test method," linear least-squares regression model," Amur River

Real-Time Position and Attitude Estimation for Homing and Docking of an Autonomous Underwater Vehicle Based on Bionic Polarized Optical Guidance

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Journal of Ocean University of China 2020年第5期19卷 1042-1050页

作者： CHENG Haoyuan CHU Jinkui ZHANG Ran GUI Xinyuan TIAN Lianbiao The key laboratory for Micro/Nano Technology and System of liaoning province Dalian University of TechnologyDalian 116024China

As an important tool for marine exploration, the autonomous underwater vehicle(AUV) must home in and dock at a docking station(DS) to be recharged, repaired, or to exchange information at set intervals. However, the complex and hostile underwater environment makes this process challenging. This study proposes a real-time method based on polarized optical guidance for determining the position and attitude of the AUV relative to its DS. Four polarized artificial underwater landmarks are positioned at the DS, which are recognized by the AUV vision system. Compared with light intensity, the polarization of a light beam is known to be better maintained at greater propagation distances, especially in underwater environments. The proposed method, which is inspired by the ability of marine animals to communicate, calculates the pose parameters in less than 10 ms without any other navigational information. The simulation results reveal that the angle errors are small and the position errors are no more than 0.116 m within 100 m in the coastal ocean. The results of underwater experiments further demonstrate the feasibility of the proposed method, which extends the operating distance of the AUV beyond what is currently possible while maintaining the precision of traditional optical guidance.

关键词： polarization optical guidance AUV underwater docking position and attitude estimation

Feature based problem hardness understanding for requirements engineering

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Science China(Information Sciences) 2017年第3期60卷 88-107页

作者： Zhilei REN He JIANG Jifeng XUAN Shuwei ZHANG Zhongxuan LUO key laboratory for Ubiquitous Network and Service Software of liaoning province Dalian University of Technology School of Software Dalian University of Technology State key laboratory of Software Engineering Wuhan University

Heuristics and metaheuristics have achieved great accomplishments in various fields, and the investigation of the relationship between these algorithms and the problem hardness has been a hot topic in the research field. Related research work has contributed much to the understanding of the underlying mechanisms of the algorithms for problem solving. However, most existing studies consider traditional combinatorial problems as their case studies. In this study, taking the Next Release Problem(NRP) from the requirements engineering as a case study, we investigate the relationship between software engineering problem instances and heuristics. We employ an evolutionary algorithm to evolve NRP instances, which are uniquely hard or easy for the target heuristic(Greedy Randomized Adaptive Search Procedure and Randomized Hill Climbing in this paper). Then, we use a feature-based method to estimate the hardness of the evolved instances, with respect to the target heuristic. Experimental results demonstrate that, evolutionary algorithm can be used to evolve NRP instances that are uniquely hard or easy to solve. Moreover, the features enable the estimation of the target heuristics’ performance.

关键词： problem hardness next release problem computational intelligence requirements engineering evolution algorithm

Insights on the possibility of SARS-CoV-2 transmission through the eyes

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International Journal of Ophthalmology(English edition) 2022年第11期15卷 1857-1863页

作者： Rui Zhu Zi-Yan Yu Lin Han Department of Ophthalmology the Fourth Affiliated Hospital of China Medical UniversityShenyang 110005Liaoning ProvinceChina Eye Hospital of China Medical University Shenyang 110005Liaoning ProvinceChina key Lens Research laboratory of liaoning province Shenyang 110005Liaoning ProvinceChina China Medical University Shenyang 110122Liaoning ProvinceChina

A novel coronavirus, named severe acute respiratory syndrome coronavirus 2(SARS-Co V-2 or 2019-nCOV), causing coronavirus disease 2019(COVID-19), has rapidly spread to most countries and regions worldwide since it broke out at the end of 2019. Epidemic of the virus produces a tremendous pressure on the global health systems. With progressive insight into SARS-Co V-2, the role of eye tissue has attracted wide attention in the spread of COVID-19. Whether SARS-Co V-2 can enter the human body through eyes and cause infection? The fact that unprotected exposure of the eyes to 2019-n Co V might have allowed the virus to infect the body implies that 2019-n COV can invade eye tissue and set foot in organism. Facing the severe challenge of preventing spread of the COVID-19, combined with the high-risk environment of ophthalmology, it is crucial to investigate ocular tropism of coronavirus. This paper explores the possibility of coronavirus transmission through the eye from aspects of probable mechanisms, clinical cases, detection of coronavirus;and puts forward precautions for ophthalmologists and nurses. Consequently, this review reveals our understanding of ocular tropism of coronavirus and contributes to determining risk of ocular transmission, raising awareness of necessary eye protection among medical workers and reducing further prevalence of SARS-Co V-2.

关键词： coronavirus SARS-CoV-2 ocular conjunctivitis

Suppress oxygen evolution of lithium-rich manganese-based cathode materials via an integrated strategy

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Green Energy & Environment 2024年第1期9卷 138-151页

作者： Wenhua Yu Yanyan Wang Aimin Wu Aikui Li Zhiwen Qiu Xufeng Dong Chuang Dong Hao Huang key laboratory of Energy Materials and Devices(liaoning province) School of Materials Science and EngineeringDalian University of TechnologyDalian116024Liaoning ProvinceChina Dalian Engineering Research Center for New Electric Power Systerms School of Electrical EngineeringDalian University of TechnologyDalian116024Liaoning ProvinceChina

Improving the reversibility of anionic redox and inhibiting irreversible oxygen evolution are the main challenges in the application of high reversible capacity Li-rich Mn-based cathode materials.A facile synchronous lithiation strategy combining the advantages of yttrium doping and LiYO_(2) surface coating is *** doping effectively suppresses the oxygen evolution during the delithiation process by increasing the energy barrier of oxygen evolution reaction through strong Y–O bond ***_(2) nanocoating has the function of structural constraint and protection,that protecting the lattice oxygen exposed to the surface,thus avoiding irreversible *** an Li^(+) conductor,LiYO_(2) nano-coating can provide a fast Li^(+) transfer channel,which enables the sample to have excellent rate *** synergistic effect of Y doping and nano-LiYO_(2) coating integration suppresses the oxygen release from the surface,accelerates the diffusion of Li^(+)from electrolyte to electrode and decreases the interfacial side reactions,enabling the lithium ion batteries to obtain good electrochemical *** lithium-ion full cell employing the Y-1 sample(cathode)and commercial graphite(anode)exhibit an excellent specific energy density of 442.9 Wh kg^(-1) at a current density of 0.1C,with very stable safety performance,which can be used in a wide temperature range(60 to-15℃)stable *** result illustrates a new integration strategy for advanced cathode materials to achieve high specific energy density.

关键词： Lithium-rich manganese-based cathodes Lithium ion batteries Oxygen redox Oxygen evolution Integrated strategy

A nanonewton-scale biomimetic mechanosensor

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Microsystems & Nanoengineering 2023年第4期9卷 45-56页

作者： Chi Zhang Mengxi Wu Ming Li Lixuan Che Zhiguang Tan Di Guo Zhan Kang Shuye Cao Siqi Zhang Yu Sui Jining Sun Liding Wang Junshan Liu State key laboratory of High-performance Precision Manufacturing Dalian University of Technology116024 DalianLiaoningChina key laboratory for Micro/Nano Technology and System of liaoning province Dalian University of Technology116024 DalianLiaoningChina State key laboratory of Structural Analysis for Industrial Equipment Dalian University of Technology116024 DalianChina

Biomimetic mechanosensors have profound implications for various areas,including health care,prosthetics,human‒machine interfaces,and *** one of the most important parameters,the sensitivity of mechanosensors is intrinsically determined by the detection resolution to mechanical *** this manuscript,we expand the force detection resolution of current biomimetic mechanosensors from the micronewton to nanonewton *** develop a nanocrack-based electronic whisker-type mechanosensor that has a detection resolution of 72.2 *** achieve the perception of subtle mechanical stimuli,such as tiny objects and airflow,and the recognition of surface morphology down to a 30 nm height,which is the finest resolution ever reported in biomimetic *** importantly,we explore the use of this mechanosensor in wearable devices for sensing gravity field orientation with respect to the body,which has not been previously achieved by these types of *** develop a wearable smart system for sensing the body’s posture and movements,which can be used for remote monitoring of falls in elderly *** summary,the proposed device offers great advantages for not only improving sensing ability but also expanding functions and thus can be used in many fields not currently served by mechanosensors.

关键词： mec expanding profound