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Simultaneous Determination of Nine Triterpenoids in Psidium guajava Using HPLC-DAD-ELSD and Pressurized Liquid Extraction

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Simultaneous Determination of Nine Triterpenoids in Psidium ...

第十四届全国中药和天然药物学术研讨会

作者： Ying Chen Jian-Bo Wan Song-Lin Li qing-wen zhang South University of Science and Technology of China

＜正＞Psidium guajava,a food and medicine dual purposes plant normally cultivated in tropical and subtropical regions,is widely believed to have anti-diabetes and anti-cancer activities around the *** it is revealed t...

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A Novel Strategy for Rapid Quantification of 20（S）-protopanaxatriol and 20（S）-protopanaxadiol saponins in Panax notoginseng,*** and ***

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A Novel Strategy for Rapid Quantification of 20（S）-protopa...

第十四届全国中药和天然药物学术研讨会

作者： Fa-Xiang Xu Cen Yuan Jian-Bo Wan qing-wen zhang University of Macau

20（S）-protopanaxatriol saponins（PTS）and 20（S）-protopanaxadiol saponins（PDS）are well known as main bioactive components of Panax genus,including ***,*** and *** composition and proportion of PTS and PDS varied greatly according to *** the facts that PTS and PDS exhibit different and even antagonistic pharmacological effects,it is meaningful to develop an approach to rapidly quantify PTS and PDS in Panax *** the present study,a novel strategy for qualitative and quantitative determination of PTS and PDS in ***,*** and ***,was proposed,based on the overlapping peaks of main components of PTS（calibrated by ginsenoside Rg1） and PDS（calibrated by ginsenoside Rb1）.The analysis was performed by high performance liquid chromatography coupled with evaporative light scattering detection（HPLC-ELSD）.Under the specific chromatographic conditions,all samples showed two overlapping peaks containing several main ginsenosides belongs to PTS and PDS,*** overlapping peaks were also identified by *** on sum and ratio of PTS and PDS,60 tested Panax samples were divided into three main clusters according to *** findings suggested that this strategy provides a simple and rapid approach to quantify PTS and PDS in Panax herbs.

关键词： Panax 20(S)-protopanaxatriol saponins 20(S)-protopanaxadiol saponins overlapping peak HPLC-ELSD

2-Methoxystypandrone induces iNOS expression by H_2O_2-dependent JNK activation for multiple cancer cell death

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中国药理学与毒理学杂志 2015年第S1期29卷 22-22页

作者： wen SUN Jiao-lin BAO Wei LIN wen-wen ZHAO Jin-jian LU qing-wen zhang Xiu-ping CHEN State Key Laboratory of Quality Research in Chinese Medicine Institute of Chinese Medical SciencesUniversity of Macao

OBJECTIVE To investigate the mechanism of anticancer effect of 2-methoxystypandrone(2-MS),a natural naphthoquinone isolated from Polygonum cuspidatum *** *** types of cancer cells were investigated in the research(A549,MCF7,B16-F10).Flow cytometer was used to determine ROS/RNS *** blotting was used to detect related protein *** assay,GSH/GSSG(reduced glutathione/oxidized glutathione)assay were performed using commercial *** knockdown was used to silence cj-un N-terminal kinase(JNK)and ***-performance liquid chromatography(HPLC)was used to detect the direct reaction of 2-MS with *** 2-MS induced cytotoxity towards a panel of cancer cells,with less effect on normal cells.2-MS induced necroptosis in A549 cell and apoptosis in B16-F10 and MCF7cells.2-MS increased phosphorylation of JNK in three types of cancer *** of JNK with SP600125 or silencing JNK attenuated 2-MS-induced cell *** also activated iNOS expression and led to nitric oxide(NO)generation in three cancer ***-induced nitrative stress was responsible for DNA damage and necroptosis in A549 *** also inhibited NF-κB expression and induced intrinsic apoptosis in B16-F10 and *** NO scavenger hemoglobin and silencing iNOS can partially reverse 2-MS-induced cell ***,we found that all of these were attributed to induction of hydrogen peroxide(H2O2),which was caused by glutathione(GSH)depletion through interaction of 2-MS with *** interaction was validated through cell-free HPLC *** the H2O2 scavenger catalase and exogenous GSH can significantly reverse the 2-MS-induced cell *** catalase did not protect against the decrease in GSH *** contrast,there showed no clear increase of both H2O2 and NO in non-carcinoma liver cell *** Taken together,a medicinal plant-derived 1,4-napthoquinone,induced iNOS expression by H2O2-dependent JNK activation,caused nitrative stres

关键词： 2-methoxystypandrone anticancer iNOS JNK 1,4-napth

Stable photocurrent-voltage characteristics of perovskite single crystal detectors obtained by pulsed bias

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Chinese Physics B 2024年第4期33卷 209-214页

作者：刘新陈之龙王虎张雯清董昊王鹏祥邵宇川 Laboratory of Thin Film Optics Shanghai Institute of Optics and Fine MechanicsChinese Academy of SciencesShanghai 201800China Center of Materials Science and Optoelectronics Engineering University of Chinese Academy of SciencesBeijing 100049China Key Laboratory of Materials for High-Power Laser Shanghai Institute of Optics and Fine MechanicsChinese Academy of SciencesShanghai 201800China Key Laboratory for Ultrafine Materials of Ministry of Education Shanghai Engineering Research Center of Hierarchical NanomaterialsSchool of Materials Science and EngineeringEast China University of Science and TechnologyShanghai 200237China School of Microelectronics Shanghai UniversityShanghai 201899China Hangzhou Institute for Advanced Study University of Chinese Academy of SciencesHangzhou 310024China

Photocurrent-voltage characterization is a crucial method for assessing key parameters in x-ray or y-ray semiconductor detectors,especially the carrier mobility lifetime ***,the high biases during photocurrent measurements tend to cause severe ion migration,which can lead to the instability and inaccuracy of the test *** the mixed electronic-ionic charac teristics,it is imperative to devise novel methods capable of precisely measuring photocurrentvoltage characteristics under high bias conditions,free from interference caused by ion *** this paper,pulsed bias is employed to explore the photocurrent-voltage characteristics of MAPbBr_(3) single *** method yields stable photocurrent-voltage characteristics at a pulsed bias of up to 30 V,proving to be effective in mitigating ion *** fitting the modified Hecht equation,we determined the mobility lifetime products of 1.0×10^(2) cm^(2)·V^(-1)for hole and 2.78×10~(-3)cm^(2)·V^(-1)for *** approach offers a promising solution for accurately measuring the transport properties of carriers in perovskite.

关键词： perovskites ion migration pulsed bias mobility lifetime product

Enhancement of anticancer Efcacy of chemotherapeutics by escin against cholangiocarcinoma cells

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Enhancement of anticancer Efcacy of chemotherapeutics by esc...

生命的分子机器及其调控网络——2012年全国生物化学与分子生物学学术大会

作者： wen-qing zhang Dong-Yan Shen Shan-Shan Li Ling Tian Xin Dong You-Xiong Xiong qing-Xi Chen State Key Laboratory of Cellular Stress Biology School of Life SciencesXiamen University

Purpose To assess the potential use of escin as an adjunct therapy,we sought to evaluate the interaction of between escin and chemotherapeutic agents in cholangiocarcinoma *** MTT assay was employed to determine cytotoxicity of escin alone and com-bination with chemotherapeutics in QBC939 and QBC939/*** between escin and selected chemotherapeutics(5- Fu,VCR,bile extract) were quantitated by calculating the combination index and dose reduction index for determinatioin of synergism or ***,expression of mutidrug-resistence and apoptosis related proteins were measured.

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逆向工程中基于共轴立体视觉的曲面边界测量（英文）

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光子学报 2017年第2期46卷 164-180页

作者：卢科青王文张敏赵春峰杭州电子科技大学机械工程学院机械电子工程研究所杭州310018

针对逆向工程中引导性曲面边界信息的快速获取问题,系统地研究了共轴立体视觉测量方法,建立该方法的数学模型,详细分析了摄像机焦距、基线距等系统结构参数及被测点空间位置对测量精度的影响,通过数学分析确定摄像机基线距的最佳取值范... 详细信息

针对逆向工程中引导性曲面边界信息的快速获取问题,系统地研究了共轴立体视觉测量方法,建立该方法的数学模型,详细分析了摄像机焦距、基线距等系统结构参数及被测点空间位置对测量精度的影响,通过数学分析确定摄像机基线距的最佳取值范围,研究共轴立体视觉测量系统特殊的极线几何关系.提出基于共轴立体视觉的曲面边界快速测量方法,利用三坐标测量机的精密机械系统及精确的空间定位能力,用单个摄像机以两次共轴定位摄取图像的方式实现共轴立体视觉测量功能,然后利用共轴立体视觉外极线相互平行且通过各自像平面主点的特殊极线几何关系简化同源像点匹配过程,从而快速获取被测曲面的边界信息.实验结果表明:用基于三坐标测量机的单摄像机共轴立体视觉测量方法获取的曲面边界平均误差为0.268mm,基本满足逆向工程中对引导性曲面边界的测量精度要求.

关键词：立体视觉逆向工程边界提取图像处理图像匹配

知识价值导向政策对产业集群发展的影响——来自湖北自勺经验

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中国软科学 2016年第12期 182-192页

作者：潘文卿张晓寒清华大学经济管理学院北京100084

运用基于知识价值导向的集群政策推动产业集群发展成为近30年来区域经济发展中的重要现象。大多数集群政策工具的积极效用在处理市场失灵与稳定市场均衡等理论框架下已被证实,基于此,假设在不同种类的知识价值导向政策与产业集群的发展... 详细信息

运用基于知识价值导向的集群政策推动产业集群发展成为近30年来区域经济发展中的重要现象。大多数集群政策工具的积极效用在处理市场失灵与稳定市场均衡等理论框架下已被证实,基于此,假设在不同种类的知识价值导向政策与产业集群的发展状况之间存在一般关系,公共服务平台政策、教育培训类政策、公共研究型政策、专项财政资金补贴、合作网络政策与集群发展之间存在正相关关系。通过对湖北省2008年一2015年实施知识价值导向政策后的调查数据的计量分析发现,公共服务平台政策与教育培训政策对集群发展产生显著的正效应,政府能够通过鼓励并支持培训、信息、物流、咨询、技术推广等产品和服务来推动集群发展;公共研究型政策、专项财政补贴政策和合作网络政策未对集群发展产生显著的正效应,这意味着部分集群政策蕴含着政府失败的风险。

关键词：集群政策产业集群影响

Remote Sensing CO,CO_2 in Vehicle Emissions Based on TDLAS

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光机电信息 2007年第5期24卷 25-30页

作者： WANG Tie-dong LIU wen-qing zhang Yu-jun LIU Jian-guo DONG Feng-zhong WANG Min WANG Xiao-mei XU Min Key Laboratory of Environment Optics and Technology Anhui Institute of Optics and Fine Mechanics Chinese Academy of SciencesHefei 230031China

Knowing the quantity of pollutants that the vehicle fleet is emitting to the air has become a vital problem in almost every major city in China. Finding and fixing gross polluters is therefore very important to control the urban air quality and protect the human health and the environment. Remote sensing is an important advance in the technology of on-road vehicle emissions testing because it is fast, mobile, and unobtrusive. This on-road vehicle emissions remote system is designed to measure the carbon monoxide, carbon dioxide and opacity from the vehicles's tailpipe based on the Tunable Diode Laser Absorption Spectroscopy (TDLAS). There are several advantages of this system such as compact design and easy of use. The measurement principle and optical layout of the instrument has been described in this paper. Field testing at Beijing and Hefei were conducted over one year, more than 6 000 vehicles were tested. This vehicle emissions remote system has been shown to be able to measure CO,CO2 and opacity from individual at highway speeds. In parallel, the plate license, speed, acceleration and length of vehicle are recognised by computer so that the owners of vehicles exceeding the permissible level of emissions can be identified.

关键词：车辆排放一氧化碳排放二氧化碳排放遥感 TDLAS

Water Buoyancy and Deformation of Foundation Soil under Deepseated Box Foundations for Four Multi-Storied Buildings in Shanghai

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Water Buoyancy and Deformation of Foundation Soil under Deep...

作者： wen-qing zhang Xi-Hong Zhao Yong-An Yin Yu-Ping Qian Min-Bao Cao Tongji University,Shanghai

＜正＞This paper is based on the results of observations of box foundations for mulitist（?）ried buildings in Shanghai,reanging from 10 to 20 *** is divided into th（?）e parts:the first part discussing the problem of water buoyancy below the foundation base;the second part dealing with the deformation properties of foundation soil,in which a tentative method for calculating settlements of deeply embedded box foundation is also presented;the last part giving the observed results of the longitudiual deflection and transverse tilt of box foundations,and the modified method for estimating transverse tilt.

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