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10 kV配电网架空线路设计要点分析

设备监理 2024年第1期 56-59页

作者：蔡俊明福州万山电力咨询有限公司福州363005

本文对10 kV配电网架空线路的设计要点进行了深入分析和研究。从设计前的准备工作、可研初设一体化设计、施工图设计3个方面详细阐述了10 kV配电网架空线路设计的内容;架空线路的设计需要考虑气象条件、杆塔选型、导线选用、柱上设备选... 详细信息

本文对10 kV配电网架空线路的设计要点进行了深入分析和研究。从设计前的准备工作、可研初设一体化设计、施工图设计3个方面详细阐述了10 kV配电网架空线路设计的内容;架空线路的设计需要考虑气象条件、杆塔选型、导线选用、柱上设备选择以及防雷与接地设计等因素,设计过程中需要充分考虑线路的稳定性、安全性等,以提高整体电力供应的可靠性、稳定性和经济性。

关键词： 10 kV 配电网架空线路设计要点气象条件

10 kV配电线路带电作业危险点及预控措施分析

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科技资讯 2024年第15期22卷 196-198页

作者：阿布都吉利力·艾海提袁莉陈孟国网伊犁伊河供电有限责任公司新疆伊宁835000

10 kV配电线路是城市与农村电力供应的重要组成部分,但带电作业存在严重的安全隐患。通过讨论10 kV配电线路带电作业的危险性及预防措施,指出了带电作业预控在保障人员安全、降低事故发生概率、提高作业效率和确保电力系统稳定运行方面... 详细信息

10 kV配电线路是城市与农村电力供应的重要组成部分,但带电作业存在严重的安全隐患。通过讨论10 kV配电线路带电作业的危险性及预防措施,指出了带电作业预控在保障人员安全、降低事故发生概率、提高作业效率和确保电力系统稳定运行方面的必要性,分析了10 kV配电线路带电作业的主要危险点,如触电风险、高空作业风险等,提出加强培训、严格现场勘查、增强安全防护、注重工具管理和制订应急预案等一系列预控措施。

关键词： 10 kV 配电线路带电作业危险点预控措施

三维20节点六面体和10节点四面体单元的高精度中节点集中质量矩阵

维普期刊数据库评论

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力学学报 2023年第9期55卷 2043-2055页

作者：侯松阳王东东吴振宇林智炜厦门大学土木工程系福建省滨海土木工程数字仿真重点实验室福建厦门361005

对于工程分析中常用的三维20节点六面体和10节点四面体单元,采用行求和法得到的集中质量矩阵由于包含负质量元素,难以直接用于动力分析.虽然常用的主对角元素放大法,即HRZ方法,可以有效规避负质量元素,但是该方法仍缺乏理论层面的精度分... 详细信息

对于工程分析中常用的三维20节点六面体和10节点四面体单元,采用行求和法得到的集中质量矩阵由于包含负质量元素,难以直接用于动力分析.虽然常用的主对角元素放大法,即HRZ方法,可以有效规避负质量元素,但是该方法仍缺乏理论层面的精度分析.本文首先以三维20节点六面体单元为例,构造一种包含待定参数的广义集中质量矩阵,并将HRZ集中质量矩阵作为特例涵盖其中,进而建立了20节点六面体单元广义集中质量矩阵的频率精度表达式.然后,通过参数优化,提出20节点六面体单元的中节点集中质量矩阵构造方法,并从理论上证明其精度优于HRZ集中质量矩阵.该中节点集中质量矩阵形式简单,非常便于推广到10节点四面体单元.此外,利用中节点集中质量矩阵含有主对角零质量元素的特点,通过静力凝聚建立了相应的动力分析降阶模型,在保证计算精度的同时可大幅提升计算效率.自由振动和时程分析结果均表明,对于三维20节点六面体单元和10节点四面体单元,中节点集中质量矩阵的计算精度明显高于HRZ集中质量矩阵.

关键词： 20 节点六面体单元 10 节点四面体单元主对角元素放大法中节点集中质量矩阵频率精度降阶模型

Effective suppression of stimulated Raman scattering in half 10 kW tandem pumping fiber lasers using chirped and tilted fiber Bragg gratings

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Photonics Research 2019年第2期7卷 167-171页

作者： MENG WANG ZEFENG WANG LE LIU QIHAO HU HU XIAO XIAOJUN XU College of Advanced Interdisciplinary Studies National University of Defense Technology State Key Laboratory of Pulsed Power Laser Technology Hunan Provincial Key Laboratory of High Energy Laser Technology

The average power of fiber lasers has been scaled deeply into the kW regime in the past years. However, stimulated Raman scattering(SRS) is still a major factor limiting further power scaling. Here, we have demonstrated for the first time, to the best of our knowledge, the suppression of SRS in a half 10 kW tandem pumping fiber amplifier using chirped and tilted fiber Bragg gratings(CTFBGs). With specially self-designed and manufactured CTFBGs inserted between the seed laser and the amplifier stage, a maximum SRS suppression ratio of >15 dB in spectrum is observed with no reduction in laser efficiency. With one CTFBG, the effective output power is improved to3.9 kW with a beam quality M2 factor of ～1.7 from 2; with two CTFBGs, the effective laser power reaches 4.2 kW with an increasing ratio of 20% and an M2 factor of ～1.8, and further power improvement is limited by the power and performance of the 1018 nm pump sources. This work provides an effective SRS suppression method for high-power all-fiber lasers, which is useful for further power scaling of these systems.

关键词： Effective stimulated Raman 10 kW

The separation and recovery of copper(Ⅱ), nickel(Ⅱ), cobalt(Ⅱ), zinc(Ⅱ),and cadmium(Ⅱ) in a sulfate-based solution using a mixture of Versatic 10 acid and Mextral 984H

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Chinese Journal of Chemical Engineering 2017年第6期25卷 760-767页

作者： Yinxuan Qiu Limei Yang Songtao Huang Zhongguang Ji Yan Li National Engineering Laboratory of Biohydrometallurgy General Research Institute for Non-Ferrous Metals Beijing 100088 China

We studied the separation and recovery of copper(Ⅱ), nickel(Ⅱ), cobalt(Ⅱ), zinc(Ⅱ), and cadmium(Ⅱ) from magnesium and calcium, using synergistic solvent extraction(SSX) in a typical hydrometallurgical waste solution. A mixture of Versatic 10 acid and Mextral 984 H, diluted with Mextral DT100, was used to obtain fundamental data on p H and distribution isotherms, as well as the kinetics of extraction and stripping. We also investigated the main effects and interactions of common solvent extraction factors: the extraction p H at equilibrium, the temperature, and the extractant concentration. The synergistic effect for extracting metals was confirmed. The results showed that the addition of Mextral 984 H enhanced the separation factors of copper, nickel, cobalt,zinc, and cadmium over magnesium and calcium. Compared with Versatic 10 acid alone, for a mixture of0.5 mol·L^(-1) Versatic 10 acid/0.5 mol·L^(-1)Mextral 984 H, Δp H50 values of copper, nickel, cobalt, zinc, and cadmium were found to be N 2.0, 3.30, 2.85, 0.95, and 1.32 p H units, respectively. The Δp H_(50)(Zn–Mg)and Δp H_(50)(Zn–Ca)values were 3.27 and 2.25, respectively, indicating easy separation and recovery of copper, nickel, zinc, cobalt,and cadmium. The extraction and stripping of copper, cobalt, zinc, and cadmium were fast, with 90% of the metal transferred in 2 min. We next studied whether the metals could be stripped from the extracted liquid selectively in sequence, by using sulfuric acid at different concentrations. The influence of the molecular structure of the oxime and carboxylic acid components upon the synergistic effects was identified by numerical *** separation of copper, nickel, cobalt, and zinc over magnesium and calcium was achieved with this synergistic solvent extraction system.

关键词： Water treatment Solvent extraction Versatic 10 acid Mextral 984HRecovery

Progress of the 10 J water-cooled Yb:YAG laser system in RCLF

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High Power Laser Science and Engineering 2014年第3期2卷 78-85页

作者： Jian-Gang Zheng Xin-Ying Jiang Xiong-Wei Yan Jun Zhang Zhen-Guo Wang Deng-Sheng Wu Xiao-Lin Tian Xiong-Jun Zhang Ming-Zhong Li Qi-Hua Zhu Jing-Qin Su Feng Jing Wan-Guo Zheng Research Center of Laser Fusion (RCLF) CAEP

The high repetition rate 10 J/10 ns Yb:YAG laser system and its key techniques are *** amplifiers in this system have a multi-pass V-shape structure and the heat in the amplifiers is removed by means of laminar water *** the main amplifier,the laser is four-pass,and an approximately 8.5 J/1 Hz/10 ns output is achieved in the primary *** far-field of the output beam is approximately 10 times the diffraction *** of the higher levels of amplified spontaneous emission(ASE) in the main amplifier,the output energy is lower than *** the end we discuss some measures that can improve the properties of the laser system.

关键词： Yb:YAG V-shape amplifier water-cooled 10 J laser system

Complex method of the plane elasticity in 2D quasicrystal with point group 10 mm tenfold rotational symmetry and holey problems

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Science China(Technological Sciences) 2003年第3期46卷 326-336页

作者：刘官厅范天佑 School of Science Beijing Institute of Technology

The complex method of the plane elasticity in 2D quasicrystal with point group 10 mm tenfold rotational symmetry is established. First displacement potential function in the quasicrystal is represented by four analytic functions. Then by utilizing the properties of analytic function and through a great deal of derivation, the complex representations of stresses and displacementscomponents of phonon fields and phason fields in the quasicrystal are given, which are the theo-retical foundation for this method. From this theory, and by the help of conformal transformations in the theory of complex function, the problems of elliptic hole in the quasicrystal are solved. Its spe-cial cases are the solutions of well-known crack problem. Meanwhile, the results show that even if under the self-counterbalance force in the quasicrystal plane with elliptic hole, the stress compo-nents of phonon fields are also related to material constants of the quasicrystal when the phonon fields and phason fields are coupled, which is another distinctive difference from the properties of classical elastic theory. Besides, the present work is generalization and application of the complex method in the classical elastic theory established by Muskhelishvili to 2D quasicrystal. As in the classical elastic theory, if only conformal transformation from the quasicrystal plane to unit circle isfound, any holey and crack problem in the quasicrystal plane could be solved.

关键词： point group 10 mm, 2D quasicrystal, plane elasticity, conformal transformation, elliptic hole.

Effect of the interleukin 10 polymorphisms on interleukin 10 production and visceral hypersensitivity in Chinese patients with diarrhea-predominant irritable bowel syndrome

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Chinese Medical Journal 2019年第13期132卷 1524-1532页

作者： Shi-Wei Zhu Zuo-Jing Liu Qing-Hua Sun Li-Ping Duan Department of Gastroenterology Peking University Third HospitalBeijing 100191China

Background:Irritable bowel syndrome (IBS),a functional gastrointestinal disorder,is characterized by cytokine ***,decreased plasma interleukin 10 (IL-10) level was reported in patients with IBS,which may be due to genetic ***,there are no reports correlating the IL-10 polymorphisms with IL-10 production in patients with *** study aimed to analyze the effect of IL-10 polymorphisms on IL-10 production and its correlation with the clinical symptoms in Chinese patients with diarrhea-predominant IBS (IBS-D).Methods:Two IL-10 single nucleotide polymorphisms (rs1800871 and rs1800896) were detected in 120 patients with IBS-D and 144 healthy controls (HC) using *** symptom severity score,Bristol scale,hospital anxiety,and depressive scale (HADS) were used to evaluate the clinical symptoms,as well as the psychological status and visceral sensitivity of the ***-10 levels in the plasma and peripheral blood mononuclear cell (PBMC) culture supernatant were measured using enzyme-linked immunosorbent assay,while those in ileal and colonic mucosal biopsies were measured using ***:The frequency of rs1800896 C allele was significantly lower in the patients with IBS-D than that in the HC (odds ratio:0.49,95% confidence interval:0.27-0.92,P =0.0240).The IL-10 levels in the plasma (P =0.0030) and PBMC culture supernatant (P =0.0500) of the CT genotype subjects were significantly higher than those in the TT genotype *** CT genotype subjects exhibited a higher pain threshold in the rectal distention test than the TT genotype ***,IL-10 rs1800871 GG genotype subjects showed an increase in the HADS score compared to other genotype ***:IL-10 rs1800896 C allele is correlated with higher IL-10 levels in the plasma and the PBMC culture supernatant,which is associated with a higher pain threshold in the Chinese patients with *** study provides an explicit relationship of

关键词： Irritable bowel syndrome Interleukin 10 Polymorphisms Visceral hypersensitivity Depression

Study of spatial distribution of sandy desertification in North China in recent 10 years

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Science China Earth Sciences 2004年第Z1期47卷 78-88页

作者： WANG Tao, WU Wei, XUE Xian, SUN Qingwei & CHEN GuangtingKey Laboratory of Desert and Desertification, Cold and Arid Regions Environmental and Engineering Research Institute, Chinese Academy of Sciences, Lanzhou 730000, China Department of Environment Engineering, Peking University, Beijing 100871, China Key Laboratory of Desert and Desertification Cold and Arid Regions Environmental and Engineering Research Institute Chinese Academy of Sciences Lanzhou China Department of Environment Engineering Peking University Beijing China

Sandy desertification is a land degradation characterized by wind erosion, mainly resulted from the excessive human activities in arid, semiarid and part of sub-humid regions in North China. It is one of main kinds of desertification/land degradation as well as water-soil erosion and salinization in China. Rapid and continuous spread of sandy desertification during last 50 years has created a major environmental and socio-economic problem in North China. Remote sensing monitored results in 2000 showed that the sandy desertified land area has been 38.57×104 km2. The area of potential to slightly sandy desertified land is 13.93×104 km2, moderately land 9.977×104 km2, severely land 7.909×104 km2 and very severely land 6.756×104km2. Sandy desertification mainly occurs in the semi-arid mixed farming-grazing zone and its northern rangeland zone, semi-arid dryland rainfed cropping zone and arid oasis-desert margin zone. The average annually developmental rate of sandy desertified land increased from 2,100tion in North China is "overall deterioration, while local rehabilitation". Already achieved rehabilitation results and monitoring assessment show that about 60% of desertified land in North China can be restored under the conditions of rational land-use ways and intensity.

关键词： sandy desertified land, spatial distribution, remote sensing monitoring, last 10 years, North China.