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A New Placement Scheme of Distributed Generation in Power Grid

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Energy and Power Engineering 2013年第4期5卷 740-745页

作者： Zhipeng Jiang Tiande Guo wei pei Academy of Mathematics and Systems Science Chinese Academy of Sciences Beijing China Institute of Electrical Engineering Chinese Academy of Sciences Beijing China University of Chinese Academy of Sciences Beijing China

Smart grid gets more and more popular today. Distributed generation is one of the key technologies, and especially, the integration problem of the distributed generation is an important issue. Especially, the location and capacity of the distributed generation play an important role for the performance of the distribution network. In this paper, an optimization model to minimize the loss cost of the unsatisfied demand is given. This model is based on a reliability computing method which avoiding power flow calculation in a previous work. Then the model is used on the IEEE-123 nodes experiment network and a result of five distributed generation placement is got.

关键词： Smart Grid Distributed Generation Optimal Integration Optimization Model

5-芳基-3,5-二乙氧基-2(5H)-呋喃酮的合成和反应机理的研究

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有机化学 2000年第6期20卷 889-892页

作者：裴伟伟王鹏北京大学化学与分子工程学院北京100871

提出了一条方便地制备5-芳基-3,5-二乙氧基-2(5H)-呋喃酮化合物的合成路线,并对合成路线的反应机理进行了研究。应用设计的路线,合成了一组新颖的高度官能团化的2(5H)-呋喃酮化合物,所有化合物的结构均经过元素分析或高分辨率质谱,IR,NM... 详细信息

提出了一条方便地制备5-芳基-3,5-二乙氧基-2(5H)-呋喃酮化合物的合成路线,并对合成路线的反应机理进行了研究。应用设计的路线,合成了一组新颖的高度官能团化的2(5H)-呋喃酮化合物,所有化合物的结构均经过元素分析或高分辨率质谱,IR,NMR和MS确证。

关键词：合成 2(5H)-呋喃酮反应机理溴反式加成

Si对Mg-4Al-1Zn-xSi合金显微组织与力学性能的影响

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材料热处理学报 2014年第8期35卷 48-52页

作者：宋佩维陕西理工学院材料科学与工程学院陕西汉中723001

采用光学显微镜(OM)、扫描电镜(SEM)、X射线衍射仪(XRD)和拉伸试验机研究了Si含量变化对Mg-4Al-1Zn-xSi(x=0.5,1.0,2.0,质量分数,%,下同)合金显微组织和力学性能的影响。结果表明:随着Si含量的增加,合金中的α-Mg基体组织逐渐细化;β-Mg... 详细信息

采用光学显微镜(OM)、扫描电镜(SEM)、X射线衍射仪(XRD)和拉伸试验机研究了Si含量变化对Mg-4Al-1Zn-xSi(x=0.5,1.0,2.0,质量分数,%,下同)合金显微组织和力学性能的影响。结果表明:随着Si含量的增加,合金中的α-Mg基体组织逐渐细化;β-Mg17Al12相由点状(块状)逐渐转变为网状分布于晶界上;大量粗大的汉字状Mg2Si相沿晶界或穿晶分布。Si含量从0.5%增加到1.0%和2.0%时,α-Mg基体晶粒的平均尺寸从25μm分别细化到20μm和10μm;汉字状Mg2Si颗粒的平均尺寸从5μm分别增大到10μm和100μm;合金的硬度逐渐提高;其抗拉强度、屈服强度和伸长率先降低后升高;合金拉伸断裂形式为准解理脆性断裂。

关键词： Mg-4Al-1Zn-xSi合金 Si含量显微组织力学性能

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植入式多通道神经微电极的发展

分析化学 2019年第10期47卷 1455-1465页

作者：魏春蓉裴为华中国科学院半导体研究所集成光电子学国家重点联合实验室中国科学院大学

人类的大脑约由800亿神经细胞构成,这些神经元之间的连接将大脑组成了一个超复杂的神经网络,要研究大脑的功能机制,破译其神经网络的信息编码原理,一个重要的方法是在大脑神经元网络中,同时观察、记录尽可能多的单个神经元活动信号。植... 详细信息

人类的大脑约由800亿神经细胞构成,这些神经元之间的连接将大脑组成了一个超复杂的神经网络,要研究大脑的功能机制,破译其神经网络的信息编码原理,一个重要的方法是在大脑神经元网络中,同时观察、记录尽可能多的单个神经元活动信号。植入式多通道神经微电极作为一种可实时记录多个神经元峰电位信号的器件,在神经信号的时间分辨率和设备的便捷性方面有着其它神经成像技术不可替代的优点。在不影响大脑功能甚至动物行为的前提下,为了在大脑中植入通道数更多的电极,需要在植入式多通道电极的材料、结构、集成方式和植入及封装方法等方面不断地进行改进创新和优化。本文简要回顾了多通道微电极技术的发展历史,重点介绍了采用微加工技术制备植入式多通道微电极的发展历程和研究现状,对未来的发展趋势进行了展望。

关键词：植入式神经微电极微加工技术微通道电极薄膜电极电极阵列评述

DITERPENOID CONSTITUENTS OF ISODON PARVIFOLIA:STRUCTURE ELUCIDATION OF NEW DITERPENOID,PARVIFOLIN

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Chinese Chemical Letters 1992年第8期3卷 633-634页

作者： Yue wei GUO pei Yuan CHENG Nanjing Institute of materia Medica,Nanjing 210009

On the basis of chemical and spectroscopic evidence,the structure of parvifolin was established as ent-7β,20-epoxy-kaurane-15-oxo-1α,6β,7β,11β,16α-pentaol.

关键词： ppm DITERPENOID CONSTITUENTS OF ISODON PARVIFOLIA

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轻质复合材料及结构热膨胀调控设计研究进展

科学通报 2017年第1期62卷 47-60页

作者：韦凯裴永茂湖南大学机械与运载工程学院工程力学系长沙410082 北京大学工学院力学系北京100871

热膨胀系数是材料热物理性能的重要参数.在温度剧烈变化服役环境下,航空航天工程中卫星、高超声速飞行器以及精密仪器仪表,微电子封装中大量结构的热变形需要精确的控制.发展热膨胀可调控的材料具有重要的科学意义和工程应用价值.轻质... 详细信息

热膨胀系数是材料热物理性能的重要参数.在温度剧烈变化服役环境下,航空航天工程中卫星、高超声速飞行器以及精密仪器仪表,微电子封装中大量结构的热变形需要精确的控制.发展热膨胀可调控的材料具有重要的科学意义和工程应用价值.轻质复合材料凭借其轻量化,力学性能优异且热膨胀系数可设计的优点已成为热变形控制领域的重要材料.本文首先概括了材料和结构的热变形控制在工程中的重要应用以及已有低、负膨胀均质材料的研究现状.其次详细介绍了层合、颗粒增强及拓扑优化复合材料的热膨胀设计研究成果.最后重点综述了轻质点阵复合材料的几何结构设计方法,热膨胀调控机理,制备工艺及实验表征的最新研究成果.

关键词：复合材料热膨胀调控点阵结构优化设计轻量化

A novel linear microprobe array for the fabrication of neural microelectrodes

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Science China(Technological Sciences) 2015年第2期58卷 346-351页

作者： ZHAO Shan Shan pei wei Hua ZHAO Hui WANG Yi Jun CHEN San Yuan CHEN Yuan Fang ZHANG He GUO Dong Mei GUI Qiang CHEN Hong Da State Key Laboratory on Integrated Optoelectronics Institute of Semiconductors Chinese Academy of Sciences Institute for Neural Computation University of California San Diego

A novel linear microprobe array(LMPA)has been developed by a conventional microfabrication method from *** LMPA leverages the properties of conventional microwire with additional features of naturally formed regular *** the help of periodic microprobe arrays and double-side V-grooves fabricated in advance between each pair of the two microprobes’rear ends,the number of microprobe units for assembly in one array can be flexibly chosen by cleavage fracture from the *** fabrication method was demonstrated and the prototype device was assessed by electrochemical impedance spectroscopy(EIS)and in vivo *** SNR of the spikes recorded was 6.

关键词： LMPA regular spacing cleavage fracture V-groove

Impact of interval between neoadjuvant chemoradiotherapy and surgery in rectal cancer patients

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World Journal of Gastroenterology 2020年第31期26卷 4624-4638页

作者： Shi-Wen Mei Zheng Liu Fang-Ze wei Jia-Nan Chen Zhi-Jie Wang Hai-Yu Shen Juan Li Fu-Qiang Zhao wei pei Zheng Wang Xi-Shan Wang Qian Liu Department of Colorectal Surgery National Cancer Center/Cancer HospitalChinese Academy of Medical Sciences and Peking Union Medical CollegeBeijing 100021China

BACKGROUND Epidemiologically,in China,locally advanced rectal cancer is a more common form of rectal *** neoadjuvant concurrent chemoradiotherapy can effectively reduce the size of locally invasive tumors and improve disease-free survival(DFS)and pathologic response after *** present,this modality has become the standard protocol for the treatment of locally advanced rectal cancer in many centers,but the optimal time for surgery after neoadjuvant therapy is still *** To investigate the impact of time interval between neoadjuvant therapy and surgery on DFS and pathologic response in patients with locally advanced rectal *** A total of 231 patients who were classified as having clinical stage II or III advanced rectal cancer and underwent neoadjuvant chemoradiation followed by surgery at the National Cancer Center/Cancer Hospital,Chinese Academy of Medical Sciences and Peking Union Medical College from November 2014 to August 2017 were involved in this retrospective cohort *** patients were divided into two groups based on the different time intervals between neoadjuvant therapy and surgery:139(60.2%)patients were in group A(≤9 wk),and 92(39.2%)patients were in group B(>9 wk).DFS and pathologic response were analyzed as the primary *** secondary endpoints were postoperative complications and sphincter *** For the 231 patients included,surgery was performed at≤9 wk in 139(60.2%)patients and at>9 wk in 92(39.8%).The patients’clinical characteristics,surgical results,and tumor outcomes were analyzed through univariate analysis combined with multivariate regression *** overall pathologic complete response(pCR)rate was 27.2%(n=25)in the longer time interval group(>9 wk)and 10.8%(n=15)in the shorter time interval group(≤9 wk,P=0.001).The postoperative complications did not differ between the groups(group A,5%vs group B,5.4%;P=0.894).Surgical procedures for sphincter preservation were p

关键词： Interval time Advanced rectal cancer Disease-free survival Pathologic complete response Neoadjuvant therapy Surgery Complication Sphincter preservation

Low ligation has a lower anastomotic leakage rate after rectal cancer surgery

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World Journal of Gastrointestinal Oncology 2020年第6期12卷 632-641页

作者： Jia-Nan Chen Zheng Liu Zhi-Jie Wang Fu-Qiang Zhao Fang-Ze wei Shi-Wen Mei Hai-Yu Shen Juan Li wei pei Zheng Wang Jun Yu Qian Liu Department of Colorectal Surgery National Cancer Center/Cancer HospitalChinese Academy of Medical Sciences and Peking Union CollegeBeijing 100021China Department of Surgery the Johns Hopkins University School of MedicineBaltimoreMD 21218United States

BACKGROUND For laparoscopic rectal cancer surgery,the inferior mesenteric artery(IMA)can be ligated at its origin from the aorta[high ligation(HL)]or distally to the origin of the left colic artery[low ligation(LL)].Whether different ligation levels are related to different postoperative complications,operation time,and lymph node yield remains ***,we designed this study to determine the effects of different ligation levels in rectal cancer *** To investigate the operative results following HL and LL of the IMA in rectal cancer *** From January 2017 to July 2019,this retrospective cohort study collected information from 462 consecutive rectal cancer *** to the ligation level,235 patients were assigned to the HL group while 227 patients were assigned to the LL *** regarding the clinical characteristics,surgical characteristics and complications,pathological outcomes and postoperative recovery were obtained and compared between the two groups.A multivariate logistic regression analysis was performed to evaluate the possible risk factors for anastomotic leakage(AL).RESULTS Compared to the HL group,the LL group had a significantly lower AL rate,with 6(2.8%)cases in the LL group and 24(11.0%)cases in the HL group(P=0.001).The HL group also had a higher diverting stoma rate(16.5%vs 7.5%,P=0.003).A multivariate logistic regression analysis was subsequently performed to adjust for the confounding factors and confirmed that HL(OR=3.599;95%CI:1.374-9.425;P=0.009),tumor located below the peritoneal reflection(OR=2.751;95%CI:0.772-3.985;P=0.031)and age(≥65 years)(OR=2.494;95%CI:1.080-5.760;P=0.032)were risk factors for *** were no differences in terms of patient demographics,pathological outcomes,lymph nodes harvested,blood loss,hospital stay and urinary function(P>0.05).CONCLUSION In rectal cancer surgery,LL should be the preferred method,as it has a lower AL and diverting stoma rate.

关键词： Rectal neoplasms Inferior mesenteric artery Anastomotic leakage Laparoscopy Ligation Postoperative complications