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Science China(Technological Sciences) 2021年第9期64卷 2003-2011页

作者： XU GuanPing ZHENG YouBin feng YanGe MA ShaoChen LUO Ning feng Min CHEN ShouGang WANG DaoAi State Key Laboratory of Solid Lubrication Lanzhou Institute of Chemical PhysicsChinese Academy of SciencesLanzhou 730000China School of Materials Science and Engineering Ocean University of ChinaQingdao 266100China Qingdao Center of Resource Chemistry and New Materials Qingdao 266100China

Harvesting energy from ambient environment has been considered as a promising strategy for driving portable electronic devices in a sustainable way. A wind driven triboelectric-electromagnetic hybrid nanogenerator has been fabricated to convert wind energy into electricity. It is composed of an electromagnetic generator(EMG) and a triboelectric nanogenerator(TENG) with the output power of 35 and 0.32 mW, respectively when the wind speed is 5 m/s. Generally, TENG shows a low current output with a high voltage output characteristic, on the contrary the EMG shows a high current output and a low voltage output. This hybrid nanogenerator overcomes these problems and exhibits comprehensive and efficient performance on scavenging ***, in view of the output performance and charging ability of the hybrid nanogenerator, it shows high stability, making it suitable for charging capacitors or batteries and driving portable electronics sustainably. A new structure of integrated TENG and EMG was designed to harvest wind energy, which shows potential applications in portable and small device power supply system, especially in the areas of remote mountains, deserts, islands, etc., as emergency power supply.

关键词： TENG electromagnetic generator wind energy self-powered selective power supply

New photometric studies for two deep,low-mass ratio overcontact binaries:Y Sex and V1363Ori

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Research in Astronomy and Astrophysics 2021年第11期21卷 189-201页

作者： Yuan-Gui Yang Shuang Wang Hui-Yu Yuan Hai-Geng dai School of Physics and Electronic Information Huaibei Normal UniversityHuaibei 235000China

We present new photometry for two contact binaries,Y Sex and V1363 Ori,which were observed by three small telescopes in *** using the W-D method,the absolute parameters are updated from new BVR light curves and previous radial velocity *** identify that two binaries are deep,lowmass ratio(DLMR)overcontact binaries with q≤0.25 and f≥50%.From the temperature-luminosity diagram,the primary components are slightly evolved main-sequence stars,whose evolutionary ages are~2.51 Gyr for Y Sex and~3.56 Gyr for V 1363 Ori,*** the(O-C)curves,it is found that the orbital periods may be undergoing secular increase with cyclic variations,which may be interpreted either by magnetic activity cycles or by the light-time orbit *** period increasing,this kind of DLMR overcontact binaries,such as Y Sex and V1363 Ori,will evolve into the rapid-rotating single stars.

关键词： binaries(including multiple):close binaries:eclipsing stars:fundamental parameters stars:individual(Y Sex,V1363 Ori)

Backward stochastic differential equations with rank-based data

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Science China Mathematics 2018年第1期61卷 27-56页

作者： Zhen-qing Chen Xinwei feng Department of Mathematics University of Washington School of Mathematics Shandong University Department of Statistics The Chinese University of Hong Kong

In this paper, we investigate Markovian backward stochastic differential equations(BSDEs) with the generator and the terminal value that depend on the solutions of stochastic differential equations with rankbased drift coefficients. We study regularity properties of the solutions of this kind of BSDEs and establish their connection with semi-linear backward parabolic partial differential equations in simplex with Neumann boundary condition. As an application, we study the European option pricing problem with capital size based stock prices.

关键词： backward stochastic differential equations ranked particles named particles reflected Brownian motion partial differential equations viscosity solution

Effect of Sc on Al_(3)Fe phase and mechanical properties of as-cast AA5052 aluminum alloy

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China Foundry 2024年第3期21卷 257-264页

作者： Yang Li Qing Yu feng-feng Chen Jia-wen He Hong-mei Yang Meng-nie Li Faculty of Materials Science and Engineering Kunming University of Science and TechnologyKunming 650093China

The AA5052 aluminum alloy is widely used in automobile and aerospace manufacturing,and with the development of light-weight alloys,it is required that these materials exhibit better mechanical *** studies have demonstrated that the addition of Sc to aluminum alloys can improve both the microstructure and properties of the *** this study,the effect of Sc on the Fe-rich phase and properties of the AA5052 aluminum alloy was studied by adding 0%,0.05%,0.2%,and 0.3%*** results show that with the increase of Sc,the coarse needle-like Fe-rich phase gradually transforms into Chinese-script and then nearly spherical particles,reduce the size of Fe-rich phase,and refine the grain with increase of high angle grain boundaries(HAGBs).These microstructure changes enhance the strength of the AA5052 alloy through Sc *** ductility of the alloy is obviously improved because the addition of a lower amount of Sc changes the morphology of Fe-rich phase from needle-like into a Chinese-script,and it is subsequently reduced as a result of significant increase in HAGBs with increasing Sc content.

关键词： AA5052 aluminum alloy Al3Fe phase mechanical properties grain boundary

恶意攻击下基于分布式稀疏优化的安全状态估计

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自动化学报 2021年第4期47卷 813-824页

作者：张岱峰段海滨北京航空航天大学自动化科学与电气工程学院仿生自主飞行系统研究组北京100083 鹏城实验室深圳518000

恶意生成的量测攻击信号是导致信息物理系统(Cyber-physical system,CPS)探测失效的主要原因,如何有效削弱其影响是实现精准探测、跟踪与感知的关键问题.分布式传感器网络(Distributed sensor network,DSN)依靠多传感器协作与并行处理... 详细信息

恶意生成的量测攻击信号是导致信息物理系统(Cyber-physical system,CPS)探测失效的主要原因,如何有效削弱其影响是实现精准探测、跟踪与感知的关键问题.分布式传感器网络(Distributed sensor network,DSN)依靠多传感器协作与并行处理突破单一监测节点的任务包线,能够显著提升探测系统跟踪精度与可靠性.首先,依据压缩感知理论,将单一节点的目标运动状态估计建模为一种基于l0范数最小化的稀疏优化问题,采用正交匹配追踪法(Orthogonal matching pursuit,OMP)重构量测攻击信号,以克服采用凸优化算法求解易陷入局部最优的缺陷.通过卡尔曼滤波量测更新抵消攻击信号影响,恢复目标运动的真实状态.其次,针对错误注入攻击等复杂量测攻击形式,基于势博弈理论,提出一种分布式稀疏优化安全状态估计方法,利用多传感器节点信息交互与协作提升探测与跟踪的稳定性.仿真结果表明,所提方法在分布式传感器网络协作抵抗恶意攻击方面具有优越性.

关键词：恶意攻击分布式安全状态估计稀疏优化势博弈

Resilience optimization for multi-UAV formation reconfiguration via enhanced pigeon-inspired optimization

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Chinese Journal of Aeronautics 2022年第1期35卷 110-123页

作者： Qiang feng Xingshuo HAI Bo SUN Yi REN Zili WANG Dezhen YANG Yaolong HU Ronggen feng School of Reliability and System Engineering Beihang UniversityBeijing 100191China

This paper develops a novel optimization method oriented to the resilience of multiple Unmanned Aerial Vehicle(multi-UAV)formations to achieve rapid and accurate reconfiguration under random ***,a resilience metric is applied to reflect the effect and rapidity of multi-UAV formation resisting random ***,an optimization model based on a parameter optimization problem to maximize the system resilience is ***,an Adaptive Learning-based Pigeon-Inspired Optimization(ALPIO)algorithm is designed to optimize the resilience ***,typical formation topologies with six UAVs are investigated as a case study to verify the proposed *** experimental results indicate that the proposed scheme can achieve resilience optimization for a multi-UAV formation reconfiguration by increasing the system resilience values to 97.53%and 81.4%after random attacks.

关键词： Formation reconfiguration Parameter optimization Pigeon-inspired optimization Resilience Unmanned aerial vehicles

不同水体中有色可溶性有机物质荧光光谱定量分析研究

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光谱学与光谱分析 2007年第10期27卷 2083-2087页

作者：柳先平李磊戴金凤王小如黎先春国家海洋局第一海洋研究所现代分析室山东青岛266061

有色可溶性有机物(CDOM)是指水体中对紫外及可见光均有光吸收的溶解有机物,能对水色产生影响,是自然生态系统、水色光学遥感、水体碳循环研究中必不可少的环境因素。由于CDOM具有荧光特性,荧光光谱技术已成为开展CDOM研究的重要手段,被... 详细信息

有色可溶性有机物(CDOM)是指水体中对紫外及可见光均有光吸收的溶解有机物,能对水色产生影响,是自然生态系统、水色光学遥感、水体碳循环研究中必不可少的环境因素。由于CDOM具有荧光特性,荧光光谱技术已成为开展CDOM研究的重要手段,被用于CDOM的来源、分布及其变化规律的研究。文章主要利用荧光检测技术,研究了不同水体CDOM的发射荧光光谱峰面积、荧光峰强度与其浓度间的变化关系,发现在低浓度范围内,发射光谱峰面积和荧光强度与CDOM浓度具有良好的线性关系(r2>0.98);不同浓度的CDOM水溶液的发射光谱峰面积及其荧光强度随浓度的变化趋势是一致的。文章首次利用低浓度下CDOM的发射光谱峰面积与浓度间的线性关系,建立了适合于水体中组成复杂的CDOM的定量分析方法,拓展了荧光分析技术在CDOM研究中的应用。

关键词：有色可溶性有机物定量分析发射光谱峰面积

Jianpi Qingchang decoction alleviates ulcerative colitis by inhibiting nuclear factor-κB activation

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World Journal of Gastroenterology 2017年第7期23卷 1180-1188页

作者： Lie Zheng Ya-Li Zhang Yan-Cheng dai Xuan Chen De-Liang Chen Yue-Ting dai Zhi-Peng Tang Department of Gastroenterology Longhua Hospital Affiliated to Shanghai University of Traditional Chinese Medicine Institute of Digestive Diseases Shanghai University of Traditional Chinese Medicine

To investigate the therapeutic effect of Jianpi Qingchang decoction (JPQCD) on dextran sulfate sodium (DSS)-induced ulcerative colitis (UC) in ***57BL/c mice were injected intragastrically with 5% DSS instead of drinking water for 7 d, and their body weight, diarrhea severity and fecal bleeding were monitored, while the mice in the control group were treated with standard drinking water, without DSS. After 7 d, the DSS drinking water was changed to normal water and the DSS group continued with DSS water. The control and DSS groups were given normal saline by intragastric injection. The 5-aminosalicylic acid (5-ASA) group was treated orally with 5-ASA at a dose of 100 mg/kg daily. The JPQCD group was treated orally with JPQCD at a dose of 17.1 g/kg daily. On day 14, the colon length was measured, the colorectal histopathological damage score was assessed, and protein levels of interleukin (IL)-1β, IL-8 and tumor necrosis factor-alpha (TNF-α) in colon supernatants were measured by enzyme-linked immunosorbent assay. mRNA expression of IL-1β, IL-8, TNF-α and nuclear factor-kappa B (NF-κB) was detected by real-time quantitative polymerase chain reaction. Western blotting was used to detect the protein expression of NF-κB and inhibitor of kappa *** inflammation occurred in the mice administered DSS, including the symptoms of losing body weight, loose feces/watery diarrhea and presence of fecal blood; all these symptoms worsened at 7 d. The colons of mice treated with DSS were assessed by histological examination, and the results confirmed that acute inflammation had occurred, as evidenced by loss of colonic mucosa and chronic inflammatory cell infiltration, and these features extended into the deeper layer of the colon walls. The expression levels of IL-1β, IL-8 and TNF-α in the DSS group were higher than those in the control group (P < 0.05), and the expression levels of IL-1β, IL-8 and TNF-α in the JPQCD and 5-ASA groups were lower than those in the

关键词： Jianpi Qingchang decoction Dextran sodium sulfate Ulcerative colitis Nuclear factor-κB Inflammation

1-Methoxycarbony-β-carboline from Picrasma quassioides exerts anti-angiogenic properties in HUVECs in vitro and zebrafish embryos in vivo

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Chinese Journal of Natural Medicines 2018年第8期16卷 599-609页

作者： LIN Qing-Hua QU Wei XU Jian feng feng HE Ming-Fang Department of Natural Medicinal Chemistry China Pharmaceutical University Key Laboratory of Biomedical Functional Materials China Pharmaceutical University Institute of Translational Medicine College of Biotechnology and Pharmaceutical EngineeringNanjing Tech University

Angiogenesis is a crucial process in the development of inflammatory diseases,including cancer,psoriasis and rheumatoid ***,several alkaloids from Picrasma quassioides had been screened for angiogenic activity in the zebrafish model,and the results indicated that 1-methoxycarbony-β-carboline(MCC) could effectively inhibit blood vessel *** this study,we further confirmed that MCC can inhibit,in a concentration-dependent manner,the viability,migration,invasion,and tube formation of human umbilical vein endothelial cells(HUVECs) in vitro,as well as the regenerative vascular outgrowth of zebrafish caudal fin in *** the zebrafish xenograft assay,MCC inhibited the growth of tumor masses and the metastatic transplanted DU145 tumor *** proteome profile array of the MCC-treated HUVECs showed that MCC could down-regulate several angiogenesis-related self-secreted proteins,including ANG,EGF,b FGF,GRO,IGF-1,PLG and *** addition,the expression of two key membrane receptor proteins in angiogenesis,TIE-2 and u PAR,were also down-regulated after MCC *** together,these results shed light on the potential therapeutic application of MCC as a potent natural angiogenesis inhibitor via multiple molecular targets.

关键词： 1-Methoxycarbony-β-carboline Angiogenesis inhibitor HUVEC Zebrafish Anti-angiogenic index

Chemo-damage modeling and cracking analysis of AAR-affected concrete dams

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Science China(Technological Sciences) 2013年第6期56卷 1449-1457页

作者： PAN JianWen feng YunTian XU YanJie JIN feng ZHANG ChuHan ZHANG BingYin State Key Laboratory of Hydroscience and Engineering Tsinghua University Civil and Computational Engineering Centre College of EngineeringSwansea University

A chemo-damage model for cracking analysis of concrete dams affected by alkali-aggregate reaction (AAR) is proposed, which combines the plastic-damage model for concrete with the AAR kinetics law. The chemo-damage model is first verified by a stress-free AAR expansion test. The expansion deformation obtained from the simulation is in good agreement with the measurement, demonstrating that the proposed model has a sufficient accuracy to predict the expansion of AAR-affected concrete. Subsequently, the expansion deformation and cracking process of the AAR-affected Fontana gravity dam is analyzed. It shows that permanent displacements in the upstream direction and the vertical direction are gradually increased during the long-term operation period, and that their maximal values reach 1.6 and 3.6 cm, respectively. A crack is observed on the wall in the foundation drainage gallery, and extends towards the downstream face of the dam. With the further development of AAR, another crack forms on the downstream face, and then intersects with the gallery crack to penetrate the downstream side profile of the dam. The third crack occurs in the upstream side wall of the gallery and propagates a short distance towards the upstream face of the dam. The simulated cracking pattern in the dam due to AAR is similar to the in situ observation.

关键词： concrete dams alkali-aggregate reaction (AAR) expansion deformation cracking