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New Constituents from the Fresh Stems of Opuntia Dillenii

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Journal of Chinese Pharmaceutical Sciences 2003年第1期12卷 1-5页

作者： QIUYing-kun chenying-jie PEIYu-pin MatsudaHisashi YoshikawaMasayuki DepartmentofTraditionalChineseMedicine ShenyangPharmaceuticalUniversityShenyang110016China DepartmentofPharmacognosy KyotoPharmaceuticalUniversityKyotoJapan607-8412

Aim To study the chemical composition of Opuntia dillenii Haw. Methods Manykinds of chromatogra-phy methods were used in the isolation procedure, while the structures ofisolated compounds were determined on the aids of NMR and MS spectral analysis. Result Three newcompounds, together with 14 known compounds, were isolated form the 80% ethanolic extract of itsstems. Conclusion The three new compounds, opuntioside Ⅰ (2), 4-ethoxyl-6-hydroxymethyl-α-pyrone(3) and kaempferol 7-O-β-D-glucopyranosyl (1→4)-β-D-glucopyranoside (4), were characterized.

关键词： opuntia dillenii opuntioside Ⅰ 4-ethoxyl-6-hydroxymethyl-α-pyrone kaempferol 7- O-β-D-glucopyranosyl (1→4)-β-D-glucopyranoside

Aging Characteristics of XLPE Insulation of 110 kV Cables in the Initial Stage of Operation

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Energy Engineering 2021年第5期118卷 1537-1548页

作者： jie Chen Wei Zhang Man Ding Libin Hu Jinpeng Wang chenying Li Jingying Cao State Grid Jiangsu Electric Power Co. Ltd.Research InstituteNanjing211103China Hohai University Nanjing211100China

The aging characteristics of the XLPE insulation of 110 kV power cables in the initial stage of operation are studied in this *** XLPE insulation from cables with different running time was tested by using electrical and physicochemical methods,from which the degradation state of XLPE under multiple stresses during operation was *** broadband dielectric spectrum test taken from 10–1 to 10^(6) Hz showed that the dielectric constant and dielectric loss of the XLPE insulation first decrease and then increase with the increase of cable running time,which show obvious variation until 10 years of *** AC breakdown strengths of the XLPE insulation of operated cables with the service year no longer than 10 years were higher than that of new *** mechanical properties of the XLPE insulation showed no dependence with the cable running *** crystallinity and perfection of the crystallization area were found to be enhanced during operation and the polar functional groups inside the XLPE insulation were found to be determined not only by the cross-linking by-products but also by the oxidation process during cable *** experimental results in this paper are important for improving the operation reliability and reducing the maintenance costs of the cables.

关键词： XLPE power cable aging dielectric property aggregation structure

基于高斯投影的变电站巡检机器人定位建图技术

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测控技术 2024年第6期43卷 14-20页

作者：柏仓邱刚陈杰谭笑曹京荥李陈莹国网江苏省电力有限公司江苏南京211103 国网江苏省电力有限公司电力科学研究院江苏南京211103

保障变电站的安全是电力供应的关键要素,因此变电站的巡检工作是不可或缺的。目前,采用机器人进行自动化巡检是变电站巡检领域的重要趋势。获得变电站的平面地图是实现变电站自动化巡检的关键。目前传统的定位建图方案,如同步定位与建图... 详细信息

保障变电站的安全是电力供应的关键要素,因此变电站的巡检工作是不可或缺的。目前,采用机器人进行自动化巡检是变电站巡检领域的重要趋势。获得变电站的平面地图是实现变电站自动化巡检的关键。目前传统的定位建图方案,如同步定位与建图(Simultaneous Localization and Mapping,SLAM)、离线全球定位系统(Global Positioning System,GPS)定位等,往往存在特征识别困难、建图时间过长或者地图所需存储空间过大等缺点。基于此,提出了一种基于高斯投影的变电站巡检机器人定位建图技术。采集完工作区域内外边界和障碍区域的边界点后,通过高斯投影,将采集到的地理位置坐标转换为平面直角坐标,并通过射线法实现平面栅格地图的建立。再根据已有的栅格地图信息和实时接收的机器人当前位置信息实现定位功能。实验验证了该定位建图技术的可行性,该方法可极大地提升建图速度,减少地图所需的存储空间,建立的地图可用于巡检机器人后续的路径规划和导航。

关键词：巡检机器人定位建图高斯投影射线法坐标转换栅格地图

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Boosting the Electrochemical Performance of Li-and Mn-Rich Cathodes by a Three-in-One Strategy

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Nano-Micro Letters 2021年第12期13卷 311-321页

作者： Wei He Fangjun Ye jie Lin Qian Wang Qingshui Xie Fei Pei chenying Zhang Pengfei Liu Xiuwan Li Laisen Wang Baihua Qu Dong-Liang Peng State Key Lab of Physical Chemistry of Solid Surface Collaborative Innovation Center of Chemistry for Energy MaterialsCollege of Materials and Pen-Tung Sah Institute of Micro-Nano Science and TechnologyXiamen UniversityXiamen 361005People’s Republic of China College of Chemistry and Chemical Engineering Xiamen UniversityXiamen 361005People’s Republic of China Zhengzhou Key Laboratory of Big Data Analysis and Application Henan Academy of Big DataZhengzhou UniversityZhengzhou 450002People’s Republic of China Fujian Provincial Key Laboratory of Light Propagation and Transformation College of Information Science and EngineeringHuaqiao UniversityXiamen 361021People’s Republic of China Shenzhen Research Institute of Xiamen University Shenzhen 518000People’s Republic of China

There are plenty of issues need to be solved before the practi-cal application of Li-and Mn-rich cathodes,including the detrimental voltage decay and mediocre rate capability,*** doping can e ectively solve the above problems,but cause the loss of *** introduction of appropriate defects can compensate the capacity loss;however,it will lead to structural mismatch and stress ***,a three-in-one method that combines cation–polyanion co-doping,defect construction,and stress engineering is *** co-doped Na^(+)/SO_(4)^(2-)can stabilize the layer framework and enhance the capacity and voltage *** induced defects would activate more reac-tion sites and promote the electrochemical ***,the unique alternately distributed defect bands and crystal bands structure can alleviate the stress accumulation caused by changes of cell parameters upon ***,the modified sample retains a capacity of 273 mAh g^(-1)with a high-capacity retention of 94.1%after 100 cycles at 0.2 C,and 152 mAh g^(-1)after 1000 cycles at 2 C,the corresponding voltage attenuation is less than 0.907 mV per cycle.

关键词： Li-and Mn-rich cathodes Cation–polyanion co-doping Defect and stress engineering Good structure stability Electrochemical performance

10 kV一母多馈电缆线路过电压传递影响因素分析

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电瓷避雷器 2024年第1期 131-140页

作者：曹京荥陈杰谭笑李陈莹胡丽斌方春华陶玉宁游海鑫国网江苏省电力有限公司电力科学研究院南京210000 三峡大学电气与新能源学院湖北宜昌443000

10 kV电缆发生故障时,弧光接地会产生过电压,造成电网波动,影响供电安全。利用PSCAD建立一母多馈线模型,详细分析了不同条件下馈线条数、中性点接地电阻阻值和电缆长度对电缆中过电压传递特性的影响。结果表明:电缆馈线增加时,发生弧光... 详细信息

10 kV电缆发生故障时,弧光接地会产生过电压,造成电网波动,影响供电安全。利用PSCAD建立一母多馈线模型,详细分析了不同条件下馈线条数、中性点接地电阻阻值和电缆长度对电缆中过电压传递特性的影响。结果表明:电缆馈线增加时,发生弧光接地故障,由行波传递分流作用使传递到非故障电缆馈线过电压幅值降低;小电阻接地故障相将产生较高过电压,过电压传递到非故障馈线上时幅值仍较大,给非故障电缆绝缘产生危害;中性点接地电阻增加时,非故障馈线故障相电压幅值降低,非故障相电压故障升高;故障电缆的长度增加,非故障电缆上过电压幅值降低。研究结果可为选取合理选择参数数值,抑制过电压产生提供依据。

关键词：一母多馈线过电压弧光接地故障接地

Online Loss Parameters Diagnosis Device Development of Power Cable Insulation

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Energy and Power Engineering 2017年第4期9卷 216-223页

作者： jie Chen chenying Li Libin Hu Jingying Cao Xiao Tan State Grid Jiangsu Electric Power Research Institute Nanjing China

In southern China, power cable lines often running in water, and the state of XLPE insulation is difficult to detection effectively. This paper studied loss parameters online diagnosis technology of power cable insulation. An online loss parameters diagnosis device was development, which consists of current comparator, voltage controlled current source (VCCS), standard capacitor, GPRS wireless transmission system, control system and the data processing unit. 108 cables were detected using this device, and it was found out that one cable appeared to middle aging and eight cables appeared to slight aging. The butterfly water trees were observed in middle aging cable, which prove the effectiveness of online testing in the loss current measurement.

关键词： Loss Parameters Power Cable Insulation Onlinetesting Aging

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骨髓增殖性肿瘤基因突变的研究进展

中华血液学杂志 2014年第12期35卷 1127-1130页

作者：李晨莹金洁浙江大学血液病研究所浙江大学医学院附属第一医院血液科杭州310003

1951年,William Dameshek认识到慢性髓性白血病（CML）、真性红细胞增多症（PV）、原发性血小板增多症（ET）和原发性骨髓纤维化（PMF）具有三系骨髓异常增殖的共同特征,首先提出骨髓增殖性疾病（MPD）这一概念.2005年,国外几个研究团... 详细信息

1951年,William Dameshek认识到慢性髓性白血病（CML）、真性红细胞增多症（PV）、原发性血小板增多症（ET）和原发性骨髓纤维化（PMF）具有三系骨髓异常增殖的共同特征,首先提出骨髓增殖性疾病（MPD）这一概念.2005年,国外几个研究团队先后报道在多数PV和部分ET/PMF患者中发现JAK2V617F突变[1-4],证实了MPD可能具有相同的分子发病机制.

关键词：原发性骨髓纤维化骨髓增殖性疾病基因突变原发性血小板增多症 JAK2V617F 真性红细胞增多症慢性髓性白血病肿瘤

The protein X4 of severe acute respiratory syndrome-associated coronavirus is expressed on both virus-infected cells and lung tissue of severe acute respiratory syndrome patients and inhibits growth of Balb/c 3T3 cell line

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Chinese Medical Journal 2005年第4期118卷 267-274页

作者： chenying-yu SHUANGBao TANYa-xia MENGMin-jie HANPu MOXiao-ning SONGQuan-sheng QIUXiao-yan LUOXin GANQi-ni ZHANGXin ZHENGYing LIUShun-ai WANGXiao-ning ZHONGNan-shan MADa-long CenterforHumanDiseaseGenomics PekingUniversityBeijing100083China GuangzhouInstituteofRespiratoryDisease FirstAffiliatedHospitalGuangzhouMedicalCollegeGuangzhou510120China InstituteofMolecularImmunology FirstMilitaryMedicalUniversityofPLAGuangzhou510515China CenterforDiseaseControlandPreventionofGuangdongProvince Guangzhou510300China BeijingDitanHospital Beijing100101China

Background The genome of the severe acute respiratory syndrome-associated coronavirus ( SARS-CoV) includes sequences encoding the putative protein X4 ( ORF8, ORF7a), consisting of 122 amino acids. The deduced sequence contains a probable cleaved signal peptide sequence and a C-terminal transmembrane helix, indicating that protein X4 is likely to be a type I membrane protein. This study was conducted to demonstrate whether the protein X4 was expressed and its essential function in the process of SARS-CoV infection. Methods The prokaryotic and eukaryotic protein X4-expressing plasmids were constructed. Recombinant soluble protein X4 was purified from E. coli using ion exchange chromatography, and the preparation was injected into chicken for rising specific polyclonal antibodies. The expression of protein X4 in SARS-CoV infected Vero E6 cells and lung tissues from patients with SARS was performed using immunofluorescence assay and immunohistochemistry technique. The preliminary function of protein X4 was evaluated by treatment with and over-expression of protein X4 in cell lines. Western blot was employed to evaluate the expression of protein X4 in SARS-CoV particles. Results We expressed and purified soluble recombinant protein X4 from E. coli, and generated specific antibodies against protein X4. Western blot proved that the protein X4 was not assembled in the SARS-CoV particles. Indirect immunofluorescence assays revealed that the expression of protein X4 was detected at 8 hours after infection in SARS-CoV-infected Vero E6 cells. It was also detected in the tung tissues from patients with SARS. Treatment with and overexpression of protein X4 inhibited the growth of Balb/c 313 cells as determined by cell counting and MTT assays. Conclusion The results provide the evidence of protein X4 expression following SARS-CoV infection, and may facilitate further investigation of the immunopathological mechanism of SARS.

关键词： severe acute respiratory syndrome coronavirus protein X4

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LED企业专利诉讼关系网络分析

情报杂志 2013年第8期32卷 87-91,49页

作者：张杰李晨颖翟东升北京工业大学经济与管理学院北京100124

LED专利诉讼的日益增加,已经成为企业决策者在经营过程中面临的重要课题之一。研究LED企业间的专利诉讼关系能够帮助决策者全面认识企业专利诉讼现状,为规避专利风险和制定专利诉讼策略提供决策支持和理论指导。以LED企业间的专利诉讼... 详细信息

LED专利诉讼的日益增加,已经成为企业决策者在经营过程中面临的重要课题之一。研究LED企业间的专利诉讼关系能够帮助决策者全面认识企业专利诉讼现状,为规避专利风险和制定专利诉讼策略提供决策支持和理论指导。以LED企业间的专利诉讼案例为研究对象,运用社会网络中心性分析将企业聚成4类,分析与比较各类企业的诉讼地位及特点,进一步提出具有针对性的诉讼策略。

关键词： LED 专利诉讼社会网络分析中心性企业类型