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半密闭腔室内冲击闪络电弧观测及弧后气体逸散过程研究

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电工技术学报 2024年第3期39卷 924-934页

作者：袁涛杨泽文司马文霞邓明海任健行刘良顺输变电装备技术全国重点实验室(重庆大学) 重庆400044 国网重庆市电力有限公司奉节供电公司重庆404600

多腔室灭弧装置可保护绝缘子、抑制故障电弧存续,具有成为配电网线路防护增补措施的潜力。半密闭腔室作为多腔室灭弧装置的基本单元,腔室内冲击闪络电弧演变进程尚缺乏完备的观测手段和针对不同电极结构的直观对比,以及弧后气体状态的... 详细信息

多腔室灭弧装置可保护绝缘子、抑制故障电弧存续,具有成为配电网线路防护增补措施的潜力。半密闭腔室作为多腔室灭弧装置的基本单元,腔室内冲击闪络电弧演变进程尚缺乏完备的观测手段和针对不同电极结构的直观对比,以及弧后气体状态的量化分析。为进一步完善半密闭腔室内电弧演变过程观测方法,优化结构设计,该文搭建了用于观测半密闭腔室电弧及弧后气体演变的高速纹影系统,对比分析了开放气隙与半密闭腔室气隙、U型电极和球形电极下半密闭腔室内冲击闪络电弧演变过程,根据纹影图像数据定义密度恢复率,并采用光流法探讨了弧后气体逸散过程中气体密度恢复和速度场分布。电弧演变过程的纹影图像表明,半密闭腔室较开放气隙具有主动“吹弧”作用,由于自感应磁场的分布差异,U型电极较球形电极加速腔室内电弧运动;弧后气体演变为近似涡环结构,促使腔室出口邻近区域气体密度率先恢复,空气自恢复能力得到提升。

关键词：半密闭腔室纹影观测电弧演变电极结构弧后气体密度

不同档位脊神经后支低温等离子消融术治疗慢性关节突关节源性腰痛

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中国疼痛医学杂志 2024年第8期30卷 585-591页

作者：林鹋苗羽朱谦毛鹏司马蕾樊碧发福建省立医院疼痛科福建医科大学省立临床医学院福州大学附属省立医院福州350001 中日友好医院疼痛科北京100029

目的:探讨不同档位的低温等离子消融术(low-temperature plasma radiofrequency ablation,LTPRA)治疗慢性关节突关节源性腰痛的临床疗效及安全性,为临床提供理论依据。方法:纳入2021年2月至2022年2月在中日友好医院疼痛科接受LTPRA治疗... 详细信息

目的:探讨不同档位的低温等离子消融术(low-temperature plasma radiofrequency ablation,LTPRA)治疗慢性关节突关节源性腰痛的临床疗效及安全性,为临床提供理论依据。方法:纳入2021年2月至2022年2月在中日友好医院疼痛科接受LTPRA治疗的92例慢性关节突关节源性腰痛住院病人,根据LTPRA治疗的档位分为1档组(平均功率13 W,术区温度40℃左右,51例)与3档组(平均功率49 W,术区温度60℃左右,41例)。分别对两组术前、术后第2周、1、3、6、12个月的疼痛数字分级评分法(numerical rating scale,NRS)评分、Oswestry功能障碍指数(Oswestry disability index,ODI)、非甾体抗炎药(nonsteroidal antiinflammatory drugs,NSAIDs)和/或阿片类药物的使用情况、手术相关并发症进行随访评估以及统计学分析。结果:与术前相比,术后2周、1、3、6、12个月两组NRS评分和ODI评分均明显下降;药物使用率显著下降。组间比较发现,术后1个月至12个月3档组NRS评分均低于1档组,术后2周以及术后6个月至术后12个月,3档组ODI评分均低于1档组,差异有统计学意义。3档组中更多比例病人出现术后短期轻度并发症,但差异无统计学意义。结论:针对慢性关节突关节源性腰痛,1档、3档治疗均有效,3档的治疗效果更优、持续时间更长,术后短期可能出现轻度的并发症,但术后并发症与1档相比无明显差异。

关键词：慢性关节突关节源性腰痛低温等离子消融术不同档位 NRS评分 Oswestry功能障碍指数

Fluorescence Enhancement Ratio Dropdown at Low Fluences during Femtosecond Double Pulse Laser Ablation

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Chinese Physics Letters 2008年第7期25卷 2653-2656页

作者： sima SINGHA Robert J. GORDON 胡湛 Institute of Atomic and Molecular Physics Jilin University Changchun 130021 Department of Chemistry University of Illinois at Chicago Chicago Illinois 60607-7061 USA

In the study of double pulse ablation of materials （silicon and copper）, a dropdown of double pulse to single pulse fluorescence signal enhancement at low fluences is observed. The dropdown is analysed with a simple theoretical one-dimensional heat diffusion model and verified by fluorescence time constants change as a function of fluence. The dropdown is explained as a result of liquid-solid mixture layer at the liquid and solid boundary. The effect of the layer becomes important at low fluences.

关键词： the power-law exponents precipitation durative abrupt precipitation change

A convenient synthesis of 2-aminocyclohex-1-ene-1-carboxylic esters by FeCl_3/SiO_2 nanoparticles as robust and efficient catalyst

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Chinese Chemical Letters 2015年第6期26卷 735-738页

作者： sima Kalhor Javad Safaei-Ghomi Department of Chemistry Qom BranchIslamic Azad University

A simple and green method has been developed for the synthesis of 2-aminocyclohex-l-ene-l- carboxylic esters through a one-pot three-component condensation reaction of primary amines, ethyl acetoacetate and chalcones using FeCI3/SiO2 nanoparticles in ethanol. This method has several advantages such as high to excellent product yields in short time, using an inexpensive and reusable catalyst and available starting material.

关键词： FeCl3/SiO2 nanoparticlesMulti-component reactionsOne-pot2-Aminocyclohex-l-ene-l-carboxylicestersChalcone

Evaluating and modeling the spatiotemporal pattern of regional-scale salinized land expansion in highly sensitive shoreline landscape of southeastern Iran

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Journal of Arid Land 2018年第6期10卷 946-958页

作者： Mohammad SHAFIEZADEH Hossein MORADI sima FAKHERAN Department of Natural Resources Isfahan University of Technology

Taking an area of about 2.3×10~4 km~2 of southeastern Iran, this study aims to detect and predict regional-scale salt-affected lands. Three sets of Landsat images, each set containing 4 images for 1986, 2000, and 2015 were acquired as the main source of data. Radiometric, atmospheric and cutline blending methods were used to improve the quality of images and help better classify salinized land areas under the support vector machine method. A set of landscape metrics was also employed to detect the spatial pattern of salinized land expansion from 1986 to 2015. Four factors including distance to sea, distance to sea water channels, slope, and elevation were identified as the main contributing factors to land salinization. These factors were then integrated using the multi-criteria evaluation (MCE) procedure to generate land sensitivity map to salinization and also to calibrate the cellular-automata (CA) Markov chain (CA-Markov) model for simulation of salt-affected lands up to 2030, 2040 and 2050. The results of this study showed a dramatic dispersive expansion of salinized land from 7.7 % to 12.7% of the total study area from 1986 to 2015. The majority of areas prone to salinization and the highest sensitivity of land to salinization was found to be in the southeastern parts of the region. The result of the MCE-informed CA-Markov model revealed that 20.3% of the study area is likely to be converted to salinized lands by 2050. The findings of this research provided a view of the magnitude and direction of salinized land expansion in a past-to-future time period which should be considered in future land development strategies.

关键词： soil salinization remote sensing CA-Markov salt land expansion southeastern Iran

DEARSENICATION FROM COBALT-ARSENIC CONCENTRATE BY VACUUM DISTILLATION

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中国有色金属学会会刊：英文版 1994年第2期4卷 4-9页

作者： Cao, Mingyan Dai, Yongnian sima, Zhongzhi Kunming Inst of Technology Kunminga China

ＤＥＡＲＳＥＮＩＣＡＴＩＯＮＦＲＯＭＣＯＢＡＬＴ－ＡＲＳＥＮＩＣＣＯＮＣＥＮＴＲＡＴＥＢＹＶＡＣＵＵＭＤＩＳＴＩＬＬＡＴＩＯＮＤＥＡＲＳＥＮＩＣＡＴＩＯＮＦＲＯＭＣＯＢＡＬＴ－ＡＲＳＥＮＩＣＣＯＮＣＥＮＴＲＡＴＥＢＹ... 详细信息

ＤＥＡＲＳＥＮＩＣＡＴＩＯＮＦＲＯＭＣＯＢＡＬＴ－ＡＲＳＥＮＩＣＣＯＮＣＥＮＴＲＡＴＥＢＹＶＡＣＵＵＭＤＩＳＴＩＬＬＡＴＩＯＮＤＥＡＲＳＥＮＩＣＡＴＩＯＮＦＲＯＭＣＯＢＡＬＴ－ＡＲＳＥＮＩＣＣＯＮＣＥＮＴＲＡＴＥＢＹＶＡＣＵＵＭＤＩＳＴＩＬＬＡＴＩＯ...

关键词： vacuum distillation cobalt-arsenic concentratc condensate residue redistillation

sima Wensen: A Pioneer for China-France Cultural Exchange

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China & The World Cultural Exchange 2014年第4期80卷 36-39页

作者： sima Xiaoshen

January.27th,2014 marked a monumental date.50 years ago today,China and France issued a joint communiquéand declared the establishment of diplomatic *** June 6th,1964,China and France successfully established diploma... 详细信息

关键词：中国文化交流法国外交关系

Efficient hydrolysis of cellulose to glucose catalyzed by lignin-derived mesoporous carbon solid acid in water

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Chinese Journal of Chemical Engineering 2020年第7期28卷 1866-1874页

作者： Shuai Wang Guobao sima Ying Cui Longjun Chang Linhuo Gan College of Chemical Engineering Huaqiao UniversityXiamen 361021China Key Laboratory of Pulp and Paper Science&Technology of Ministry of Education/Shandong Province Qilu University of Technology(Shandong Academy of Science)Jinan 250353China

Two kinds of mesoporous carbon solid acids(LDMCE-SO3H and LDMCS-SO3H)were successfully prepared using masson pine alkali lignin as carbon source by evaporation-induced self-assembly(EISA)and salt-induced selfassembly(SISA)followed by sulfonation,*** terms of preparation process,SISA(self-assembly in water and preparation time of 2 days)is greener and simpler than EISA(self-assembly in ethanol and preparation time of 7 days).The prepared LDMCE-SO3H and LDMCS-SO3H exhibit obvious differences in structural characteristics such as pore channel structure,specific surface area,mesopore volume and the density of-SO3H ***,the catalytic performances of LDMCE-SO3H and LDMCS-SO3H were investigated in the hydrolysis of microcrystalline cellulose in water,and the glucose yields of 48.99%and 54.42%were obtained under the corresponding optimal reaction *** importantly,the glucose yields still reached 28.85%and 30.35%after five runs,and restored to 39.02%and 45.98%through catalysts regeneration,respectively,demonstrating that LDMCE-SO3H and LDMCS-SO3H have excellent recyclability and regenerability.

关键词： Biomass Evaporation-induced self-assembly Salt-induced self-assembly Mesoporous carbon solid acid Catalysis Hydrolysis

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日本社区养老服务与设施发展历程探索及启示

住宅科技 2024年第2期44卷 38-44页

作者：司马蕾井高佑纪同济大学建筑与城市规划学院高密度人居环境生态与节能教育部重点实验室高松建设株式会社

社区型养老服务与设施具有良好的社会与经济效益,也是我国养老事业未来发展的重点。日本的社区型养老服务历经20余年演进,探索出具有特色的设施体系,其近年的发展基于区域统括护理的理念,提升服务与设施设置的灵活性和人性化程度。文章... 详细信息

社区型养老服务与设施具有良好的社会与经济效益,也是我国养老事业未来发展的重点。日本的社区型养老服务历经20余年演进,探索出具有特色的设施体系,其近年的发展基于区域统括护理的理念,提升服务与设施设置的灵活性和人性化程度。文章回顾日本养老政策的发展历程,梳理社区养老服务模式与小规模多功能设施出现的背景及特点,分析区域统括护理体系的概念与发展现状,探讨日本经验对我国社区养老服务特别是乡村地区养老设施发展带来的启示。

关键词：人口老龄化社区养老养老设施区域统括护理体系

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