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高效液相色谱法测定大麦苗及其产品中大麦黄苷和皂草黄苷

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分析试验室 2024年第8期43卷 1124-1131页

作者：王环陈涛马家麟汪园沈裕虎谭亮李玉林中国科学院西北高原生物研究所青海省农产品质量检测工程技术研究中心西宁810001

建立了高效液相色谱(HPLC)法测定大麦苗及其产品中2.黄酮大麦黄苷和皂草黄苷的含量,研究了10个品种的青稞苗、 2.品种的皮大麦苗、 1个未知品种的大麦苗以及11个大麦苗产品中的大麦黄苷和皂草黄苷含量的差异。样品采用60%(V/V)乙醇作... 详细信息

建立了高效液相色谱(HPLC)法测定大麦苗及其产品中2.黄酮大麦黄苷和皂草黄苷的含量,研究了10个品种的青稞苗、 2.品种的皮大麦苗、 1个未知品种的大麦苗以及11个大麦苗产品中的大麦黄苷和皂草黄苷含量的差异。样品采用60%(V/V)乙醇作为提取溶剂,液料比为50 mL/g,室温超声3. min,采用C18(2.0 mm×4.6 mm, 5μm)色谱柱分离,甲醇/0.5%甲酸水溶液(3./70, V/V)为流动相进行洗脱,对大麦黄苷在3.5 nm、皂草黄苷在3.8 nm波长下检测。在优化条件下,大麦黄苷和皂草黄苷在0.2.0~100μg/mL范围内线性关系良好,加标回收率为96.2.~100%,大麦黄苷的检出限和定量限分别为9 mg/kg和2. mg/kg,皂草黄苷的检出限和定量限分别为12.mg/kg和3. mg/kg。12.已知品种中,除了青稞昆仑15号,皮大麦苗Golden promise和Bonus的2.黄酮含量普遍高于其它9个青稞品种;10个青稞品种中,昆仑15号的2.黄酮含量最高。11个大麦苗产品根据2.黄酮含量可分为6组,各组之间差异显著。大麦黄苷和皂草黄苷在14种非麦苗产品中均未检出,可作为区分它们的质量标志物。本方法适用于高黄酮含量大麦苗品种筛选以及大麦苗产品的质量控制。

关键词：大麦苗大麦苗产品大麦黄苷皂草黄苷高效液相色谱法

Coupled modeling and analysis of radiometer effect and residual gas damping on proof mass in purely gravitational orbit

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Science China(Technological sciences) 2011年第4期54卷 894-902页

作者： LIU HongWei wang ZhaoKui ZHANG yulin institute of Aerospace and Material Engineering National University of Defense TechnologyChangsha 410073China School of Aerospace Tsinghua UniversityBeijing 100084China

Spacecrafts free of all but gravitational forces are important in precision navigation,gravity field measurement and basic scientific *** Inner-formation Flying System,one kind of spacecrafts free of all but gravitational forces,is used for gravitational field measurement with high *** the interfering factors on the inner-satellite is one of the keys to gravitational field *** effect and residual gas damping are both interfering forces on the inner-satellite caused by gas *** analyzing the mechanism of the two forces,a coupled model for radiometer effect and residual gas damping was established,which contained the coupling term and reflected the actual force of gas molecules on the *** simulation results showed the coupling property of radiometer effect and residual gas damping:The actual force of gas molecules is directly proportional to the average pressure in the cavity and the largest cross-sectional area of the inner-satellite,but is inversely proportional to the square root of the average temperature in the cavity.

关键词： purely gravitational orbit proof mass radiometer effect residual gas damping coupled modeling

Amino-functionalized core-shell magnetic mesoporous composite microspheres for Pb(Ⅱ) and Cd(Ⅱ) removal

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Journal of Environmental sciences 2013年第4期25卷 830-837页

作者： yulin Tang Song Liang Juntao wang Shuili Yu Yilong wang State Key Laboratory of Pollution Control and Resource Reuse College of Environmental Science & EngineeringTongji University The institute for Biomedical Engineering & Nano Science Tongji University

Amino-functionalized Fe3.4@mesoporous SiO/ core-shell composite microspheres NH2.MS in created in multiple synthesis steps have been investigated for Pb（Ⅱ） and Cd（Ⅱ） adsorption. The microspheres were characterized by transmission electron microscope （TEM）, scanning electron microscope （SEM）, N2.adsorption-desorption, zeta potential measurements and vibrating sample magnetometer. Batch adsorption tests indicated that NH2.MS exhibited higher adsorption affinity toward Pb（Ⅱ） and Cd（Ⅱ） than MS did. The Langmuir model could fit the adsorption isotherm very well with maximum adsorption capacity of 12..2. and 51.81 mg/g for Pb（Ⅱ） and Cd（Ⅱ）, respectively, implying that adsorption processes involved monolayer adsorption. Pb（Ⅱ） and Cd（Ⅱ） adsorption could be well described by the pseudo second-order kinetics model, and was found to be strongly dependent on pH and humic acid. The Pb（Ⅱ）- and Cd（Ⅱ）-loaded microspheres were effectively desorbed using 0.01 mol/L HC1 or EDTA solution. NH2.MS have promise for use as adsorbents in the removal of Pb（Ⅱ） and Cd（Ⅱ） in wastewater treatment processes.

关键词： heavy metals adsorption magnetic mesoporous microspheres amino-functionalization

Compressed Sensing of IR-UWB Wireless Sensor Network Data Based on Two-Dimensional Measurements

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chinese Journal of Electronics 2015年第3期24卷 627-632页

作者： wang Kai LIU yulin WAN Qun JING Xiaojun Chongqing Communication institute China Electronic System Engineering Company University of Electronic Science and Technology of China Beijing University of Posts and Telecommunications

A novel Compressed sensing(CS) method based on two-dimensional measurements is proposed that can be effectively utilized in Impulse radio ultra-wideband wireless sensor networks(IR-UWB WSNs) to significantly reduce the energy consumption and sampling rate in sensor data transferring. We start by establishing the CS measurement model by taking both spatial and temporal correlations of Wireless sensor network(WSN) data into account. Since our model incorporates a new type of measurement matrix: the block quasi-Toeplitz structured matrix, we derive the Restricted isometry property(RIP)of the block quasi-Toeplitz structured matrix to ensure the performance of the two-dimensional recovery of WSNs data. We substantiate our mathematical analysis by numerical examples in the context of ideal spares vector and real WSN data, and results demonstrate that the approach achieves significantly saving of energy and sampling rate with small reconstruction error.

关键词： Compressed sensing Wireless sensor net-works IR-UWB Measurement Restricted isometry property

Upgrading ethylene via renewable energy-driven electrocatalysis

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Science China Chemistry 2024年

作者： Hanyu wang Dunfeng Gao Guoxiong wang Xinhe Bao State Key Laboratory of Catalysis Dalian National Laboratory for Clean Energy iChEM (Collaborative Innovation Center of Chemistry for Energy Materials) Dalian Institute of Chemical Physics Chinese Academy of Sciences University of chinese academy of sciences

Ethylene oxide （EO） and ethylene glycol （EG） are two important commodity chemicals and are industrially produced from petroleum-derived ethylene via thermocatalytic processes. The overoxidation of ethylene and the implementation of high temperature and pressure lead to substantial CO2.mission. Renewable energy-driven electrocatalysis provides a low-carbon route for upgrading ethylene under mild conditions, especially when it couples with ethylene electrosynthesis from CO2. In this minireview, we summarize recent achievements in the selective electrocatalytic oxidation of ethylene to EO and EG. Three main reaction routes including direct electrocatalytic oxidation with water, indirect electrocatalytic oxidation with halide mediators,and tandem electrocatalytic and thermocatalytic oxidation with hydrogen peroxide intermediate, are discussed. Some representative catalyst systems and reactor designs are exemplified. We discuss the existing scientific and technical challenges of electrocatalytic ethylene upgrading in terms of reaction rate, selectivity, and long-term stability, and propose future research directions and opportunities for pushing the process towards practical application.

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考虑日变化过程的寒区隧道温度场解析解与现场监测研究

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铁道科学与工程学报 2024年第6期21卷 2406-2416页

作者：张力杰穆彦虎田毅王玉林朱小明张坤郑波李凌洁中国科学院西北生态环境资源研究院冻土工程国家重点实验室甘肃兰州730000 中国科学院大学北京100049 甘肃省公路交通建设集团有限公司甘肃兰州730000 甘肃省交通规划勘察设计院股份有限公司甘肃兰州730030 西北民族大学土木工程学院甘肃兰州730124 中铁西南科学研究院有限公司四川成都611731

负温环境是隧道冻害发生的必要条件,因此隧道内气温、衬砌和围岩体温度的空间分布与时间变化过程是寒区隧道冻害机理和防治研究的关键。目前,已有研究多采用月平均值来描述隧道内的温度环境及其影响因素,忽略了其日变化过程,可能低估隧... 详细信息

负温环境是隧道冻害发生的必要条件,因此隧道内气温、衬砌和围岩体温度的空间分布与时间变化过程是寒区隧道冻害机理和防治研究的关键。目前,已有研究多采用月平均值来描述隧道内的温度环境及其影响因素,忽略了其日变化过程,可能低估隧道内负温段长度和冻结深度以及衬砌结构经历的冻融作用,由此造成保温设防设计的不足。以青藏高原东北缘的一高海拔寒区公路特长隧道为例,通过对洞内气温的自动连续观测,统计分析了隧道内气温的日变化特征。运用叠加原理将寒区隧道径向温度场分为稳态和瞬态,在求解瞬态温度场过程中采用Laplace变换,同时考虑隧道内气温的日变化和年变化过程,构建了包括保温层、衬砌和围岩体等多层介质的寒区隧道径向温度场解析解,对比分析了考虑与不考虑气温日变化过程隧道衬砌结构温度的变化规律。结果表明,隧道内气温的日变化幅度在进、出口段较为显著,日振幅可达11℃以上,随着进深增加逐渐减小,至隧道中部气温日振幅降至2.以内。同时,隧道内气温日振幅表现出明显的季节性,冷季明显大于暖季。考虑气温的日变化过程的解析解能够更准确地反映隧道结构所经历的冻结时长和冻融循环次数,与隧道结构层内实测温度的波动范围更加接近。现场监测结果和理论解析方法对于寒区隧道衬砌混凝土抗冻等级选择和冻融损伤预测以及衬砌挂冰和路面结冰预警等具有积极意义。

关键词：寒区隧道温度场日变化现场监测解析解

High-Voltage and Fast-Charging Lithium Cobalt Oxide Cathodes: From Key Challenges and Strategies to Future Perspectives

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Engineering 2024年第6期37卷 105-127页

作者： Gongrui wang Zhihong Bi Anping Zhang Pratteek Das Hu Lin Zhong-Shuai Wu State Key Laboratory of Catalysis Dalian Institute of Chemical PhysicsChinese Academy of SciencesDalian 116023China Dalian National Laboratory for Clean Energy Chinese Academy of SciencesDalian 116023China

Lithium-ion batteries(LIBs)with the“double-high”characteristics of high energy density and high power density are in urgent demand for facilitating the development of advanced portable ***,the lithium ion(Li+)-storage performance of the most commercialized lithium cobalt oxide(LiCoO_(2.,LCO)cathodes is still far from satisfactory in terms of high-voltage and fast-charging capabilities for reaching the double-high ***,we systematically summarize and discuss high-voltage and fast-charging LCO cathodes,covering in depth the key fundamental challenges,latest advancements in modification strategies,and future perspectives in this *** and elaborated discussions are first presented on key fundamental challenges related to structural degradation,interfacial instability,the inhomogeneity reactions,and sluggish interfacial *** provide an instructive summary of deep insights into promising modification strategies and underlying mechanisms,categorized into element doping(Li-site,cobalt-/oxygen-site,and multi-site doping)for improved Li+diffusivity and bulkstructure stability;surface coating(dielectrics,ionic/electronic conductors,and their combination)for surface stability and conductivity;nanosizing;combinations of these strategies;and other strategies(i.e.,optimization of the electrolyte,binder,tortuosity of electrodes,charging protocols,and prelithiation methods).Finally,forward-looking perspectives and promising directions are sketched out and insightfully elucidated,providing constructive suggestions and instructions for designing and realizing high-voltage and fast-charging LCO cathodes for next-generation double-high LIBs.

关键词： Lithium cobalt oxide High energy/power density Fast-charging High-voltage Lithium-ion battery

High-dimensional quantum information processing on programmable integrated photonic chips

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Science China(Information sciences) 2023年第8期66卷 5-22页

作者： yulin CHI Yue YU Qihuang GONG Jianwei wang State Key Laboratory for Mesoscopic Physics School of Physics Peking University Frontiers Science Center for Nano-optoelectronics and Collaborative Innovation Center of Quantum Matter Peking University Peking University Yangtze Delta institute of Optoelectronics Collaborative Innovation Center of Extreme Optics Shanxi University Hefei National Laboratory

This study reviews the recent progress of high-dimensional quantum information processing with photons. We first introduce the basic language of high-dimensional quantum information, including the representation of quantum dits(qudits), unitary operations of qudit states, and the general format of quantum algorithms with qudits. We discuss experimental implementations of high-dimensional quantum information processing and quantum computing in photonic systems, particularly in integrated quantum photonic platforms. We also discuss how qudit-based quantum photonic devices and systems can be adopted for further improving qubit-based quantum computation and quantum simulation.

关键词： high-dimensional quantum information processing quantum computation integrated quantum photonics

空间辐射对肠道菌群及其代谢产物和多系统疾病的影响

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空间科学学报 2024年第5期44卷 873-883页

作者：吴竹君张昕庞玉笛邓玉林王志敏北京理工大学前沿交叉科学研究院北京100081 北京理工大学医学技术学院北京100081

维持肠道菌群的稳态对保障人体健康具有重要意义.肠道菌群在调节机体功能方面发挥着关键作用,例如消化、新陈代谢、免疫及认知等,这些生理功能通常依赖于肠道菌群的多样性、菌群结构的稳定性与微生态的平衡性.在空间环境中,航天员会受... 详细信息

维持肠道菌群的稳态对保障人体健康具有重要意义.肠道菌群在调节机体功能方面发挥着关键作用,例如消化、新陈代谢、免疫及认知等,这些生理功能通常依赖于肠道菌群的多样性、菌群结构的稳定性与微生态的平衡性.在空间环境中,航天员会受到包括空间辐射在内的诸多特殊环境因素的影响.空间辐射会造成肠道菌群失衡及其代谢产物变化,使肠道屏障功能受损,进一步引起肠道、心血管、脑及肺等多系统病理损伤.本文分析了空间飞行或模拟空间辐射下肠道菌群稳态及其代谢产物的特征性变化,以及辐射效应下肠道菌群与肠道损伤及其他多系统疾病之间的相互影响,为研究空间辐射病理机制及辐射防护措施提供参考.

关键词：空间辐射肠道菌群代谢产物辐射损伤多系统疾病