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Effects of annealing treatment on the microstructure and electrochemical properties of low-Co hydrogen storage alloys containing Cu and Fe

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Rare Metals 2011年第5期30卷 464-469页

作者： YANG Suxia LIU Zhiping han Shumin ZhanG Wei song Jianzheng State Key Laboratory of Metastable Materials Science and Technology Yanshan University Qinhuangdao 066004 China College of Environmental and Chemical Engineering Yanshan University Qinhuangdao 066004 China

The effects of annealing treatment on the microstructure and electrochemical properties of low-Co LaNi 3.55 Mn 0.35 Co 0.20 Al 0.20 Cu 0.75 Fe 0.10 hydrogen storage alloys were investigated. X-ray diffraction （XRD） analysis indicated that annealing treatment remarkably reduced the lattice strain and defects, and increased the unit-cell volume. The optical microscope analysis showed that the as-cast alloy had a crass dendrite microstructure with noticeable composition segregation, which gradually disappeared with increasing annealing temperature, and the micro-structure changed to an equiaxed structure after annealing the alloy at 1233 K. The electrochemical tests indicated that the annealed alloys demonstrated much better cycling stability compared with the as-cast one. The capacity retention at the 100th cycle increased from 90.0% （as-cast） to 94.7% （1273 K）. The annealing treatment also improved the discharge capacity. However, the high rate dischargeability （HRD） value of the annealed alloy slightly dropped, which was believed to be ascribed to the decreased exchange current density and the hydrogen diffusion coefficient in alloy bulk.

关键词： hydrogen storage alloys annealing phase structure microstructure electrochemical properties

Relative dynamics estimation of non-cooperative spacecraft with unknown orbit elements and inertial tensor

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Chinese Journal of Aeronautics 2016年第2期29卷 479-491页

作者： Yu han Zhang Xiujie Liu Lingyu Wang Shuo song Shenmin Beijing Institute of Astronautical Systems Engineering Beijing 100076 China center for control theory and guidance technology harbin institute of technology Harbin 150001 China Academy of Fundamental and Interdisciplinary Science Harbin Institute of Technology Harbin 150001 China

The state estimation for relative motion with respect to non-cooperative spacecraft in ren- dezvous and docking （RVD） is a challenging problem. In this paper, a completely non-cooperative case is considered, which means that both orbit elements and inertial tensor of target spacecraft are unknown. By formulating the equations of relative translational dynamics in the orbital plane of chaser spacecraft, the issue of unknown orbit elements is solved. And for the problem for unknown inertial tensor, we propose a novel robust estimator named interaction cubature Kalman filter （InCKF） to handle it. The novel filter consists of multiple concurrent CKFs interlacing with a max- imum a posteriori （MAP） estimator. The initial estimations provided by the multiple CKFs are used in a Bayesian framework to form description of posteriori probability about inertial tensor and the MAP estimator is applied to giving the optimal estimation. By exploiting special property of spherical-radial （SR） rule, a novel method with respect to approximating the likelihood probability of inertial tensor is presented. In addition, the issue about vision sensor＇s location inconformity with center mass of chaser spacecraft is also considered. The performance of this filter is demonstrated by the estimation problem of RVD at the final phase. And the simulation results show that the perfor- mance of InCKF is better than that of extended Kalman filter （EKF） and the estimation accuracy of oose and attitude is relatively high even in the comoletely non-coooerative case.

关键词： Cubature Kalman filter MAP estimator Non-cooperative spacecraft Relative motion Stereo vision

Semantic composition of distributed representations for query subtopic mining

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Frontiers of Information Technology & Electronic Engineering 2018年第11期19卷 1409-1419页

作者： Wei song Ying LIU Li-zhen LIU han-shi WANG Information and Engineering College Capital Normal University

Inferring query intent is significant in information retrieval tasks. Query subtopic mining aims to find possible subtopics for a given query to represent potential intents. Subtopic mining is challenging due to the nature of short queries. Learning distributed representations or sequences of words has been developed recently and quickly, making great impacts on many fields. It is still not clear whether distributed representations are effective in alleviating the challenges of query subtopic mining. In this paper, we exploit and compare the main semantic composition of distributed representations for query subtopic mining. Specifically, we focus on two types of distributed representations: paragraph vector which represents word sequences with an arbitrary length directly, and word vector composition. We thoroughly investigate the impacts of semantic composition strategies and the types of data for learning distributed representations. Experiments were conducted on a public dataset offered by the National Institute of Informatics Testbeds and Community for Information Access Research. The empirical results show that distributed semantic representations can achieve outstanding performance for query subtopic mining, compared with traditional semantic representations. More insights are reported as well.

关键词： Subtopic mining Query intent Distributed representation Semantic composition

An novel identification method of the environmental risk sources for surfacewater pollution accidents in chemical industrial parks

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Journal of Environmental Sciences 2013年第7期25卷 1441-1449页

作者： Jianfeng Peng Yonghui song Peng Yuan Shuhu Xiao Lu han State Key Laboratory of Environmental Criteria and Risk Assessment Chinese Research Academy of Environmental Sciences Department of Urban Water Environmental Research Chinese Research Academy of Environmental Sciences

The chemical industry is a major source of various pollution accidents. Improving the management level of risk sources for pollution accidents has become an urgentdemand for most industrialized countries. In pollution accidents, the released chemicals harm the receptors to some extentdepending on their sensitivity or susceptibility. Therefore, identifying the potential risk sources from such a large number of chemical enterprises has become pressingly urgent. Based on the simulation of thewhole accident process, a novel and expandable identification method for risk sources causingwater pollution accidents is presented. The newlydeveloped approach, by analyzing and stimulating thewhole process of a pollution accident between sources and receptors, can be applied to identify risk sources, especially on the nationwide scale. Three major types of losses, such as social, economic and ecological losses,were normalized, analyzed and used for overall consequence modeling. A specific case study area, located in a chemical industry park （CIP） along the Yangtze River in Jiangsu Province, China,was selected to test the potential of the identification method. The results showed that therewere four risk sources for pollution accidents in this CIP. Aniline leakage in the HS Chemical Plantwould lead to the most serious impact on the surroundingwater environment. This potential accidentwould severelydamage the ecosystem up to3.8 kmdownstream of Yangtze River, and lead to pollution over adistance stretching to 73.7 kmdownstream. The proposed method is easily extended to the nationwide identification of potential risk sources.

关键词： water pollution accident risk source identification grading chemical industry parks

Site-selective oral delivery of therapeutic antibodies to the inflamed colon via a folic acid-grafted organic/inorganic hy brid nanocomposite system

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Acta Pharmaceutica Sinica B 2022年第11期12卷 4249-4261页

作者： Sang Hoon Lee Jae Geun song Hyo-Kyung han College of Pharmacy Dongguk University-SeoulGoyang 10326South Korea

This study aimed to develop a pH-responsive folic acid-grafted organic/inorganic hybrid nanocomposite system for site-selective oral delivery of therapeutic antibodies. A folic acid-grafted aminoclay(FA-AC) was prepared via an in situ sol-gel method. Then, a drug-loaded nanocomplex was prepared via the electrostatic interaction of FA-AC with infliximab(IFX), a model antibody, and coated with Eudragit? S100(EFA-AC-IFX). FA-AC exhibited favorable profiles as a drug carrier including low cytotoxicity, good target selectivity, and capability to form a nanocomplex with negatively charged macromolecules. A pH-responsive FA-AC-based nanocomplex containing IFX(EFA-AC-IFX) was also obtained in a narrow size distribution with high entrapment efficiency(>87%). The conformational stability of IFX entrapped in EFA-AC-IFX was well maintained in the presence of proteolytic enzymes. EFA-ACIFX exhibited pH-dependent drug release, minimizing premature drug release in gastric conditions and the upper intestine. Accordingly, oral administration of EFA-AC-IFX to colitis-induced mice was effective in alleviating the progression of ulcerative colitis, while oral IFX solution had no efficacy. These results suggest that a pH-responsive FA-AC-based nanocomposite system can be a new platform for the site-selective oral delivery of therapeutic antibodies.

关键词： Infliximab Aminoclay Colonic delivery:TNF-x Infammation Folate rceptor Anibody Nanocomposite

Chromatin remodeling factors regulate environmental stress responses in plants

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Journal of Integrative Plant Biology 2021年第3期63卷 438-450页

作者： Ze-Ting song Jian-Xiang Liu Jia-Jia han Yunnan Key Laboratory of Plant Reproductive Adaptation and Evolutionary Ecology Yunnan UniversityKunming 650500China State Key Laboratory of Plant Physiology and Biochemistry College of Life SciencesZhejiang UniversityHangzhou 310027China Laboratory of Ecology and Evolutionary Biology State Key Laboratory for Conservation and Utilization of Bio‐Resources in YunnanYunnan UniversityKunming 650500China

Environmental stress from climate change and agricultural activity threatens global plant biodiversity as well as crop yield and *** sessile organisms,plants must maintain the integrity of their genomes and adjust gene expression to adapt to various environmental *** eukaryotes,nucleosomes are the basic unit of chromatin around which genomic DNA is packaged by *** enable dynamic access to packaged DNA,eukaryotes have evolved Snf2(sucrose nonfermenting 2)family proteins as chromatin remodeling factors(CHRs)that modulate the position of nucleosomes on *** plant stress responses,CHRs are recruited to specific genomic loci,where they regulate the distribution or composition of nucleosomes,which in turn alters the accessibility of these loci to general transcription or DNA damage repair ***,CHRs interplay with other epigenetic mechanisms,including DNA methylation,histone modifications,and deposition of histone *** are also involved in RNA processing at the posttranscriptional *** this review,we discuss major advances in our understanding of the mechanisms by which CHRs function during plants’response to environmental stress.

关键词： chromatin remodeling environmental stress epigenetic regulation replication stress stress responses

Constitutive Modeling for Flow Behaviors of Superaustenitic Stainless Steel S32654 during Hot Deformation

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Journal of Iron and Steel Research International 2016年第2期23卷 178-184页

作者： En-xiang PU han FENG Min LIU Wen-jie ZHENG han DONG Zhi-gang song Central Iron and Steel Research Institute Beijing 100081China School of Materials Science and Engineering Tsinghua UniversityBeijing 100084China

Hot deformation behavior of superaustenitic stainless steel S32654 was investigated with hot compression tests at temperatures of 950-1250 C and strain rates of 0. 001-10 s-1. Above 1150 ℃, with strain rate lower than 0.1 s -1 , the flow curves exhibit nearly steady state behavior, while at higher strain rate, continuous flow softening occurs. To provide a precise prediction of flow behavior for the alloy, the constitutive modeling considering effect of strain was derived on the basis of the obtained experimental data and constitutive relationship which incorporated Ar- rhenius term and hyperbolic sine type equation. The material constants α, n, Q and lnA are found to be functions of the strain and can be fitted employing eighth-order polynomial. The developed constitutive model can be employed to describe the deformation behavior of superaustenitic stainless steel S32654.

关键词： S32654 superaustenitic stainless steel hot deformation constitutive modeling

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多路径传输技术研究综述

软件学报 2025年第1期36卷 289-320页

作者：苏金树宋丛溪计晓岚徐草韩彪国防科技大学计算机学院军事科学院

多路径传输技术是指通过设备上的多个网络接口,在通信双方建立多条传输路径,实现带宽聚合、负载均衡、路径冗余,增加传输的吞吐量,提高可靠性.多路径传输技术凭借其上述优势,已被广泛应用于服务器、终端和数据中心等场景,是网络体系结... 详细信息

多路径传输技术是指通过设备上的多个网络接口,在通信双方建立多条传输路径,实现带宽聚合、负载均衡、路径冗余,增加传输的吞吐量,提高可靠性.多路径传输技术凭借其上述优势,已被广泛应用于服务器、终端和数据中心等场景,是网络体系结构和传输技术研究的重要组成,具有重要研究价值和意义.为此,从概念、核心机制等方面,系统梳理了多路径传输技术.首先概述了多路径传输的基本概念、标准化进程以及应用价值.其次,阐述多路径传输技术的核心机制,包括拥塞控制、报文调度、路径管理、重传机制、安全机制,以及面向特定应用的机制设计.对每种机制的分类方法、主要研究成果给予了总结和评述,分析总结了不同机制的优缺点与发展方向.最后,探讨了多路径传输技术研究面临的挑战,展望了未来研究方向.

关键词：多路径传输 QUIC 拥塞控制报文调度智能网络

Involvement of Opioid Peptides in the Analgesic Effect of Spinal Cord Stimulation in a Rat Model of Neuropathic Pain

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Neuroscience Bulletin 2022年第4期38卷 403-416页

作者： Fu-Jun Zhai song-Ping han Tian-Jia song Ran Huo Xing-Yu Lan Rong Zhang Ji-Sheng han Neuroscience Research Institute Peking UniversityBeijing 100191China Department of Neurobiology School of Basic Medical SciencesPeking UniversityBeijing 100191China Key Laboratory for Neuroscience Ministry of EducationNational Health CommissionPeking UniversityBeijing 100191China Wuxi hanS Health Medical Technology Co. Ltd.Wuxi 214122China Department of Integration of Chinese and Western Medicine School of Basic Medical SciencesPeking UniversityBeijing 100191China

Spinal cord stimulation(SCS)-induced analgesia was characterized,and its underlying mechanisms were examined in a spared nerve injury model of neuropathic pain in *** analgesic effect of SCS with moderate mechanical hypersensitivity was increased with increasing stimulation intensity between the 20%and 80%motor *** frequencies(2,15,50,100,10000 Hz,and 2/100 Hz dense-dispersed)of SCS were similarly ***-induced analgesia was maintained without tolerance within 24 h of continuous *** at 2 Hz significantly increased methionine enkephalin content in the cerebrospinal *** analgesic effect of 2 Hz was abolished byμorκopioid receptor *** effect of 100 Hz was prevented by aκantagonist,and that of 10 kHz was blocked by any of theμ,δ,orκreceptor antagonists,suggesting that the analgesic effect of SCS at different frequencies is mediated by different endorphins and opioid receptors.

关键词： SCS Analgesia Opioid receptors Methionine-Enkephalin Dynorphin Endorphins