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Isolation,structural determination and cytotoxic activity of two new ceramides from the root of Isatis indigotica

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Science China Chemistry 2009年第5期52卷 621-625页

作者： SUN DongDong DONG WeiWei LI Xiang zhang hanqing Pharmaceutical College Nanjing University of Chinese MedicineNanjing 210046China College of Chemistry and Chemical Engineering Nanjing University of TechnologyNanjing 210009China Institute of Botany Jiangsu Province and Chinese Academy of SciencesNanjing 210014China

Two new ceramides were isolated from the 95% EtOH extract of traditional Chinese medicinal plant Isatis indigotica. Their structures were elucidated as 1-O-β-D-glucopyranosyl-(2S, 3R)-N-(2'-hydroxypentacosanoyl)-octadeca-11E-sphingenine (1) and 1-O-β-D-glucopyranosyl-(2S,3R)-N-(2'-hydroxyhe xacosanoyl)-octadeca-11E-sphingenine (2) on the basis of spectroscopic data. Their cytotoxic effects were evaluated by using MTT method.

关键词： Isatis indigotica ceramides cytotoxic activity

The effect of large deformation and material nonlinearity on gel indentation

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Acta Mechanica Sinica 2012年第4期28卷 1058-1067页

作者： Zheng Duan Yonghao An Jiaping zhang hanqing Jiang Transport and Energy Arizona State UniversityTempe AZ 85287 USA

A gel, an aggregate of polymers with solvents, has dual attributes of solid and liquid as solvent migrates in and out of the polymer network. Indentation has recently been used to characterize the mechanical properties of gels. This paper evaluates the effects of large deformation and material nonlinearity on gel indentation through theoretical modeling and finite element analysis. It is found that large deformation significantly affects the interpretation of the experimen- tal observations and the classical relation between indenta- tion force and depth has limitations for large deformation. The material nonlinearity does not play a very important role on indentation experiment so that the poroelasticity is a good approximation. Based on these observations, this paper proposes an alternative approach to measure the mechanical properties of gels, namely, uniaxial compression experiment.

关键词： Gel indentation Large deformation Finite element simulation

High reproducibility and sensitivity of bifacial copper nanowire array for detection of glucose

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Progress in Natural Science:Materials International 2017年第3期27卷 311-315页

作者： hanqing zhang Yining Wang Xuesen Gao Zhuo Gao Yan Chen Hebei Key Laboratory of Applied Chemistry College of Environmental and Chemical EngineeringYanshan University

The ordered bifacial copper nanowire array(Cu BNWA) was synthesized by a template assisted electrochemical deposition *** morphology and structure of the as-prepared samples were investigated by field emission scanning electron microscope(FESEM) and X-ray diffraction(XRD).The results show that the ordered Cu nanowire array with uniform geometrical dimensions covered both side of the Cu *** used as the electrode for glucose detection,the minimum detectable concentration of glucose can be reached as low as 0.2 ***,the sample still showed high sensitivity and stability for glucose detection after two months placement in ambient *** excellent performances of the Cu BNWA make it a promising non-enzyme glucose detection sensor for various applications.

关键词： Cu/Copper BNWA Glucose sensor Stability Reproducibility

FedQMIX:Communication-efficient federated learning via multi-agent reinforcement learning

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High-Confidence Computing

High-Confidence Computing 2024年第2期4卷 96-104页

作者： Shaohua Cao hanqing zhang Tian Wen Hongwei Zhao Quancheng Zheng Weishan zhang Danyang Zheng Qingdao Institute of Software College of Computer Science and TechnologyChina University of Petroleum(East China)Qingdao 266580China School of Computing and Artificial Intelligence Xipu CampusSouthwest Jiaotong UniversityChengdu 611756China

Since the data samples on client devices are usually non-independent and non-identically distributed(non-IID),this will challenge the convergence of federated learning(FL)and reduce communication *** paper proposes FedQMIX,a node selection algorithm based on multi-agent reinforcement learning(MARL),to address these ***,we observe a connection between model weights and data distribution,and a clustering algorithm can group clients with similar data distribution into the same ***,we propose a QMIX-based mechanism that learns to select devices from clustering results in each communication round to maximize the reward,penalizing the use of more communication rounds and thereby improving the communication efficiency of ***,experiments show that FedQMIX can reduce the number of communication rounds by 11%and 30%on the MNIST and CIFAR-10 datasets,respectively,compared to the baseline algorithm(Favor).

关键词： Communication efficient Federated learning MARL

Selective CO_(2)-to-formic acid electrochemical conversion by modulating electronic environment of copper phthalocyanine with defective graphene

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Chinese Journal of Structural Chemistry 2023年第10期42卷 4-12页

作者： hanqing zhang Xiaoxia Wang Chen Chen Xianfeng Yang Chungli Dong Yucheng Huang Xiaoliang Zhao Dongjiang Yang School of Environmental Science and Engineering State Key Laboratory of Bio-fibers and Eco-textilesShandong Collaborative Innovation Center of Marine Bio-based Fibers and Ecological TextilesQingdao UniversityQingdao266071China Analytical and Testing Centre South China University of TechnologyGuangzhou510640China Research Center for X-ray Science Department of PhysicsTamkang UniversityTamsui25137TaiwanChina

In the carbon dioxide reduction reaction(CO_(2)RR),the activity of transition metal center depends largely on its electronic structure,since the electronic rich region enhances the adsorption of intermediates at active sites,thus improving the selectivity to reduction *** this work,we prepared CuPc/DG composite(CuPc:copper phthalocyanine;DG:defective graphene)to achieve selective CO_(2)-to-formic acid(HCOOH)electrochemical conversion through modulating the electronic structure of Cu active centers with DG via π-π *** as the electrocatalyst,the CuPc/DG composite displays a high faradaic efficiency(FE)of 44.6%−0.78 V *** for CO_(2)RR to *** current density is 5.28 mA cm^(−2) for HCOOH together with an exceptional stability throughout at least 20 h of *** the basis of density functional theory(DFT)calculation results,defects in DG can effectively promote the charge redistribution of dispersed CuPc,where electrons transfer to CuPc from defects,forming rich electronic environment around Cu *** abundance of electrons makes the d-band center of Cu approach to the Fermi level and decrease the energy barrier of CuPc/DG composite for the intermediate of ∗OCHO,thus accelerating the reduction of CO_(2) to HCOOH.

关键词： CO_(2)RR CuPc/DG composite Electron-rich region on Cu atoms HCOOH selectivity DFT calculations

Full-wave synthetic acoustic logs in porous media

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Global Geology 2012年第2期15卷 151-155页

作者： LI hanqing WANG Zhuwen zhang Xueang College of Geo-Exploration Science and Technology Jilin University Changchun 130026 China

In order to investigate the permeability of porous media,it is necessary to figure out the property of wave propagation in this medium. The authors calculated the full waveforms and the 2-dimensional spectrum of fluid saturated porous media,analyzed the wave propagation characteristics of different permeable stratums. From the theoretical acoustic pressure waveform received at the well-axis and the 2-D spectrum it is revealed that longitudinal-,transverse-,Stoneley-,pseudo-Rayleigh-,longitudinal mode-and transverse mode waves are different in characters in various permeable strata. Stoneley wave is sensitive to the change of permeability,and its frequency range and amplitude attenuation are influenced by permeability.

关键词： acoustic logging full wave-form porous media numerical calculation

Apply of Low-Carbon Technology in Building Energy Conservation in Hot Summer and Cold Winter Area

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Journal of Energy and Power Engineering 2014年第2期8卷 292-297页

作者： Jianlong Liu Jinghua Yang hanqing Wang Haiping zhang Yiyu Chen College of Civil Engineering Hunan University of Technology Zhuzhou 412007 China

Building energy conservation is the basis for carbon emission reduction, through elaborating the relationship between low carbon and energy efficient building. It points out that the construction of energy-saving emission reduction is an effective means to solve the problems of high energy consumption of the building, and it is also an important measure for China＇s carbon emission reduction. According to the climate characteristics in hot summer and cold winter area, low carbon technology suitable for the construction of energy-efficient hot summer and cold winter area is proposed which is based on the analysis of the current main building energy-saving technical measures.

关键词： Building energy conservation low-carbon building renewable energy.

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关于保险合同格式条款的裁判思维

法律适用 2020年第10期 28-38页

作者：张晗庆江苏省南京市中级人民法院

保险合同由保险人提供格式条款而订立,为矫正双方当事人缔约能力的不对称,法律对保险合同格式条款予以特别规制。某一保险条款一旦被识别为格式条款,在发生纠纷后,就要由保险人一方首先承担举证责任,证明其履行了法律规定的义务。对于... 详细信息

保险合同由保险人提供格式条款而订立,为矫正双方当事人缔约能力的不对称,法律对保险合同格式条款予以特别规制。某一保险条款一旦被识别为格式条款,在发生纠纷后,就要由保险人一方首先承担举证责任,证明其履行了法律规定的义务。对于免责条款,保险人负有较一般格式条款更重的义务。因此,保险合同中格式条款的识别、免责条款的认定,以及免责条款的效力评价是审判实务中的热点难点问题,本文通过梳理、分析审判实践中存在认识分歧的格式条款,挖掘保险案件司法裁判背后的理念和价值衡量。

关键词：保险合同格式条款裁判理念

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融资性保证保险费用条款的司法规制研究

法律适用 2024年第8期 42-54页

作者：张晗庆江苏省南京市中级人民法院金融借贷庭

近年来,融资性保证保险引发的诉讼案件呈快速增长态势,审理中发现部分保险产品约定的保险费率较高,代偿后资金占用期间的违约金负担远高于金融借款逾期还款违约责任,保险人核保时不仅未调查投保人的偿付能力、信用风险,甚至存在强制搭... 详细信息

近年来,融资性保证保险引发的诉讼案件呈快速增长态势,审理中发现部分保险产品约定的保险费率较高,代偿后资金占用期间的违约金负担远高于金融借款逾期还款违约责任,保险人核保时不仅未调查投保人的偿付能力、信用风险,甚至存在强制搭售、未履行提示说明义务等情况,导致纠纷调解率低、信访率高,判决难以执行。为保护当事人合法权益,人民法院在案件审理中对相关费用条款进行了司法规制。通过规范融资性保证保险费用条款,推动融资性保证保险健康发展,为普惠金融作出应有贡献。

关键词：融资性保证保险费用条款纠纷化解