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Chinese Journal of Natural Medicines 2018年第5期16卷 366-374页

作者： xu Fang-Fang BI Yu-An HUANG Wen-Zhe WANG zhen-zhong XIAO Wei Nanjing University of Traditional Chinese Medicine Nanjing 210000 China Jiangsu Kanion Pharmaceutical Co. Ltd. Lianyungang 222000 China State Key Laboratory of New-techfor Chinese Medicine Pharmaceutical Process Lianyungang 222001 China

Analysis errors can occur in the desorbing process of ginkgo diterpene lactone meglumine injection(GDMI) by a conventional analysis method, due to several factors, such as easily crystallized samples, solvent volatility, time-consuming sample pre-processing, fixed method, and offline analysis. Based on risk management, near-infrared(NIR) and mid-infrared(MIR) spectroscopy techniques were introduced to solve the above problems with the advantage of timely analysis and non-destructive nature towards samples. The objective of the present study was to identify the feasibility of using NIR or MIR spectroscopy techniques to increase the analysis accuracy of samples from the desorbing process of GDMI. Quantitative models of NIR and MIR were established based on partial least square method and the performances were calculated. Compared to NIR model, MIR model showed greater accuracy and applicability for the analysis of the GDMI desorbing solutions. The relative errors of the concentrations of Ginkgolide A(GA) and Ginkgolide B(GB) were 2.40% and 2.89%, respectively, which were less than 5.00%. The research demonstrated the potential of the MIR spectroscopy technique for the rapid and non-destructive quantitative analysis of the concentrations of GA and GB.

关键词： Risk management Near-infrared Mid-infrared Desorbing process Ginkgolide A Ginkgolide B

The first observation and data reduction of the Multi-wavelength Spectrometer on the New Vacuum Solar Telescope

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Research in Astronomy and Astrophysics 2013年第10期13卷 1240-1254页

作者： Rui Wang Zhi xu zhen-Yu Jin Zhi Li Yu Fu zhong Liu Yunnan Astronomical Observatory / National Astronomical Observatories Chinese Academy of Sciences University of Chinese Academy of Sciences

The Multi-wavelength Spectrometer is a medium-dispersion（R^130 000）grating spectrometer installed on the New Vacuum Solar Telescope at the Fuxian Solar Observatory,Yunnan Astronomical Observatory,Chinese Academy of *** is designed to accurately observe the velocity and magnetic fields of the *** present configuration of this spectrometer allows us to simultaneously observe three different solar spectral *** work is dedicated to showing the first observations carried out in both the Hαand Ca II 8542 A *** give a detailed description of the data reduction process,focusing on the retrieval of a flat field from the high-resolution spectral *** different methods are also performed and compared to eliminate the residual fringe in the reduced *** real spectral resolution and instrumental profile are analyzed based on the final results,which indicate that this spectrometer presently satisfies the expected performance and it is ready for further scientific observations.

关键词： instrumentation:spectrographs techniques:spectroscopic Sun:chromosphere

Feedforward compensation of the insertion devices effects in the SSRF storage ring

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Nuclear Science and Techniques 2022年第6期33卷 34-44页

作者： Xin-zhong Liu Shun-Qiang Tian xu Wu Meng Wang zhen-Tang Zhao Bo-Yuan Feng University of Chinese Academy of Sciences Shanghai 201800China Shanghai Institute of Applied Physics Chinese Academy of SciencesBeijing 100049China Shanghai Advanced Research Institute Chinese Academy of SciencesShanghai 201204China Shanghai University Shanghai 200444China Tsinghua University Beijing 100084China

The lattice of the Shanghai Synchrotron Radiation Facility(SSRF) storage ring was upgraded in the Phase-II beamline project, and thus far, 18 insertion devices(IDs) have been installed. The IDs cause closed-orbit distortions, tune drift, and coupling distortions in the SSRF storage ring, all of which are significant issues that require solutions. In this study, an ID orbit feedforward compensation system based on a response matrix using corrector coils was developed, and it was applied to all commissioned IDs in the SSRF storage ring. After correction, the maximum ID-induced horizontal and vertical orbit distortions were less than 5.0 and 3.5 μm, respectively. Some interesting phenomena observed during the measurement process were explained. Additionally, optical and coupling feedforward systems were developed using quadrupole and skew quadrupole magnets installed on the front and back of elliptically polarizing undulators(EPUs). Moreover, over nearly four months of operation, the developed strategy delivered a satisfactory performance in the SSRF storage ring.

关键词： Shanghai Synchrotron Radiation Facility(SSRF) Insertion devices(IDs) Closed-orbit distortion Tune shift Coupling Feedforward

A COST-SHARING METHOD FOR AN UNCAPACITATED FACILITY LOCATION GAME WITH PENALTIES

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Journal of Systems Science & Complexity 2012年第2期25卷 287-292页

作者： zhen WANG Dachuan xu Department of Applied Mathematics Beijing University of Technology

This paper considers a variant of the classical facility location game called the uncapacitared facility location game with penalties （UFLGWP）. Unlike the standard UFLG, each client in the UFLGWP is either assigned to an open facility or rejected by paying a penalty. The authors propose a 3-approximate cross-monotonic cost-sharing method for the UFLGWP.

关键词： Cost-sharing method cross-monotonicity facility location game.

Development of optical nanoprobes for molecular imaging of reactive oxygen and nitrogen species

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Nano Research 2018年第10期11卷 5258-5280页

作者： xu zhen Kanyi Pu School of Chemical and Biomedical Engineering Nanyang Technological University Singapore 637457 Singapore

Reactive oxygen and nitrogen species （RONS） play important roles in cell signal transduction. However, overproduction of RONS is associated with a series of pathological processes and may disrupt cellular homeostasis, causing oxidative and nitrosative stress. Accurate methods to selectively and specifically monitor RONS in living systems are required to further elucidate the biological functions of these species. Optical imaging possesses high sensitivity, high spatiotemporal resolution, and real-time imaging capability. These qualities are advantageous for the detection of RONS in living systems. This review summarizes the development of optical nanoprobes with near-infrared （NIR） fluorescent, upconversion luminescent, chemiluminescent, or photoacoustic signals for molecular imaging of RONS in living systems. In this review, we discuss the design principles and advantages of RONS-responsive activatable nanoprobes, as well as applications of these optical imaging modalities in different disease models.

关键词： optical imaging reactive oxygen andnitrogen species fluorescent upconversion luminescence chemiluminescence photoacoustic imaging

Bio-inspired motion planning for reaching movement of a manipulator based on intrinsic tau jerk guidance

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Advances in Manufacturing 2019年第3期7卷 315-325页

作者： zhen Zhang xu Yang School of Mechatronic Engineering and Automation Shanghai UniversityShanghai 200444People's Republic of China

This study proposed a bio-inspired motion planning approach for the reaching movement of a robot manipulator based on a novel intrinsic tau jerk guidance strategy,which was established by some cognitive science researchers when they studied motion patterns through *** accordance with the rules of human reaching movement,the intrinsic tau jerk guidance strategy ensures continuity of the acceleration;further,it also ensures that its value is zero at the start and end of the *** approach has been implemented on a three-degrees-offreedom 3R planar *** results show that,within a defined time,both the position gap and attitude gap can be reposefully closed,and the curves of joint velocity,acceleration,and driving torque are continuous and *** to the dynamic analysis,the proposed approach tends to consume less *** bioinspired method has the potential to be applied in particular scenarios in the future,such as a mobile robot with a manipulator exploring an unknown environment.

关键词： Bio-inspired Motion planning Manipulator Reaching movement Intrinsic tau jerk guidance

Ultralight and superelastic MXene/reduced graphene oxide aerogels for electromagnetic interference shielding

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Nano Research 2025年第1期18卷 1-9页

作者： Xinfeng Zhou Yang Dai Guoyao Yue Yiman Zhang Lulu Li zhong-zhen Yu Peng Min Hao-Bin Zhang 21 State Key Laboratory of Organic-Inorganic Composites College of Materials Science and EngineeringBeijing University of Chemical TechnologyBeijing 100029China Beijing Key Laboratory of Advanced Functional Polymer Composites College of Materials Science and EngineeringBeijing University of Chemical TechnologyBeijing 100029China Present address:BOE Technology Innovation Center BOE Technology Group Co.Ltd.Beijing 100176China Xi’an Modern Chemistry Research Institute Xi’an 710065China

Lightweight aerogels feature multifunctionality and a high porosity,yet accompanied with poor structure recovery under large strain *** this work,we develop an air bubble-ice crystal dual template and annealing strategy to integrate low density and high resilience for the conductive transition metal carbides/nitrides(MXene)composite *** air bubbles and ice crystals synergistically exclude the nanosheets to the gas-liquid interfaces,thereby constructing unique Y-shaped junctions and robust *** annealing process greatly enhances the interlayer *** external load,the Yshaped structures prevent the stress concentration at the junctions by transferring the forces to the skeleton for maintaining structural *** addition,the wrinkled and thick cell walls,together with the enhanced interlayer interactions,endow the aerogel with exceptional structural stability and *** a result,the MXene/reduced graphene oxide(RGO)composite aerogels exhibit superelasticity with reversible compressive strains of up to 95%.In addition,the electron bridging effect of the RGO sheets affords the aerogel to deliver excellent electromagnetic interference shielding performance,as high as 46.3 dB at 2.5 ***,the remarkable reshapeability of the aerogels allows for precise regulation of structure and performance(33.5-75.1 dB)by a simple wetting compression *** summary,this work offers helpful inspirations for developing lightweight and superelasticity aerogels for extensive applications.

关键词： lightweight superelasticity MXene aerogel electromagnetic interference shielding reshapeability

Inhibition roles of molybdate and borate on Q235 steel corrosion in resistance reducing agent

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Journal of Iron and Steel Research International 2023年第8期30卷 1477-1489页

作者： Yang Yang Hui Su Lan-lan Liu Song xu zhen zhong Xiao-bao Zhou Tang-qing Wu School of Materials Science and Engineering Xiangtan UniversityXiangtan 411105HunanChina State Grid Hunan Electric Power Company Limited Transmission Maintenance Changsha 410100HunanChina State Grid Hunan Electric Power Company Limited Research Institute Changsha 410007HunanChina

The effects of Na_(2)MoO_(4) and Na_(2)B_(4)O_(7) on corrosion behavior of Q235 steel in resistance reducing agent(RRA)containing sodium bentonite were studied by mass loss,scanning electron microscopy and electrochemical *** results showed that both the independent and mixed additions of Na_(2)MoO_(4) and/or Na_(2)B_(4)O_(7),can reduce the corrosion rate of Q235 steel in RRA containing sodium *** the inhibition effect of Na_(2)MoO_(4) and/or Na_(2)B_(4)O_(7)increased with their dosage *** the same dosage,the inhibition efficiency of the mixed addition of Na_(2)MoO_(4) and Na_(2)B_(4)O_(7),was higher than that of their independent *** passivation effect of Q235 steel was easy to obtain in the RRA with the mixed addition of Na_(2)MoO_(4) and Na_(2)B_(4)O_(7).The optimized inhibitor for the RRA containing sodium bentonite was the mixture of Na_(2)B_(4)O_(7) and Na_(2)MoO_(4) with a total concentration of 1.5 wt.%.Furthermore,the increase in corrosion potential E_(corr) and the decrease in corrosion current density i_(cor) in carbon steel were one of the important criteria for the formation of passivation film.

关键词： Q235 steel Resistance reducing agent Corrosion inhibitor Sodium bentonite Electrochemical impedance spectrum

LPW: an efficient data-aware cache replacement strategy for Apache Spark

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Science China(Information Sciences) 2023年第1期66卷 77-96页

作者： Hui LI Shuping JI Hua zhong Wei WANG Lijie xu zhen TANG Jun WEI Tao HUANG State Key Lab of Computer Science Institute of Software Chinese Academy of Sciences University of Chinese Academy of Sciences Nanjing Institute of Software Technology

Caching is one of the most important techniques for the popular distributed big data processing framework Spark. For this big data parallel computing framework, which is designed to support various applications based on in-memory computing, it is not possible to cache every intermediate result due to the memory size limitation. The arbitrariness of cache application programming interface(API) usage,the diversity of application characteristics, and the variability of memory resources constitute challenges to achieving high system execution performance. Inefficient cache replacement strategies may cause different performance problems such as long application execution time, low memory utilization, high replacement frequency, and even program execution failure resulting from out of memory. The cache replacement strategy currently adopted by Spark is the least recently used(LRU) strategy. Although LRU is a classical algorithm and has been widely used, it lacks consideration for the environment and workloads. As a result, it cannot achieve good performance under many scenarios. In this paper, we propose a novel cache replacement algorithm, least partition weight(LPW). LPW takes comprehensive consideration of different factors affecting system performance, such as partition size, computational cost, and reference count. The LPW algorithm was implemented in Spark and compared against the LRU as well as other state-of-the-art mechanisms. Our detailed experiments indicate that LPW obviously outperforms its counterparts and can reduce the execution time by up to 75% under typical workloads. Furthermore, the decreasing eviction frequency also shows the LPW algorithm can generate more reasonable predictions.

关键词： Spark memory cache replacement least partition weight data-aware

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RV减速器滚针轴承动态磨损特性分析

天津大学学报（自然科学与工程技术版） 2025年第1期58卷 56-67页

作者：许立新刘伟明钟家銮重庆大学高端装备机械传动全国重点实验室重庆400044 重庆大学机械与运载工程学院重庆400044

RV(rotary vector)减速器中滚针轴承径向尺寸小,所受动态接触载荷变化复杂,在实际使用中容易出现磨损失效,导致RV减速器的工作性能急剧下降,失去原有的传动精度,甚至出现故障损坏.为揭示RV减速器滚针轴承动态磨损特性,基于接触多体动力... 详细信息

RV(rotary vector)减速器中滚针轴承径向尺寸小,所受动态接触载荷变化复杂,在实际使用中容易出现磨损失效,导致RV减速器的工作性能急剧下降,失去原有的传动精度,甚至出现故障损坏.为揭示RV减速器滚针轴承动态磨损特性,基于接触多体动力学和Archard磨损理论,提出摆线针轮-滚针轴承传动机构的动力学与磨损耦合模型.该方法通过接触多体动力学求解滚针轴承动态接触载荷,分别得到滚动体与内外滚道之间的瞬时法向接触力,借助Archard磨损模型依次计算出内外滚道的瞬时磨损量,再进行累积以表达轴承内外滚道磨损形状.以RV20E-121减速器为对象,基于摆线针轮-滚针轴承传动机构的动力学与磨损耦合模型,分析滚针轴承内外滚道的动态磨损特性,获得内外滚道的累积磨损量大小和分布情况,并绘制磨损后内外滚道形状.研究结果表明:轴承内外滚道磨损量不均匀,且内滚道磨损比外滚道严重;轴承内滚道在垂直偏心距方向上的累积接触磨损量较大,轴承外滚道在摆线轮圆周方向上累积接触磨损量较大;基于RV20E-121减速器耐久疲劳试验,通过轴承滚道磨损形状检测发现,内外滚道磨损不均匀,滚针轴承内滚道的磨损情况比外滚道严峻,内滚道的磨损主要集中在垂直偏心距方向上,外滚道的磨损集中在摆线轮圆周方向上,累积磨损规律与仿真计算结果具有一致性.

关键词： RV减速器滚针轴承动力学动态磨损