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变压器 2024年第2期61卷 55-57页

作者：汪贝陈金猛张婧卿孔宪国李萍国网物资有限公司北京100120

通过对国标GB 20052-2020中能效限定值的分析,对其未覆盖的产品规格进行扩展研究。本文推算了不同容量变压器、相近电压变压器、不同调压方式变压器的能效限定值,并对高阻抗变压器的能效限定值进行了评估,合理扩展了能效变压器的范围。

关键词：变压器能效扩展高阻抗

Surface pollen and modern vegetation in Southern Xinjiang,China

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Science China Earth Sciences 2024年第2期67卷 510-530页

作者： Yun ZHANG Lixin CHEN Yaoyao XI Zhaochen kong xianguo QIAO State Key Laboratory of Black Soils Conservation and Utilization Northeast Institute of Geography and AgroecologyChinese Academy of SciencesChangchun130102China Institute of Botany Chinese Academy of SciencesBeijing100093China Key Laboratory of Cenozoic Geology and Environment Institute of Geology and GeophysicsChinese Academy of SciencesBeijing100029China University of Chinese Academy of Sciences Beijing100049China School of Geosciences and Resources China University of Geosciences(Beijing)Beijing100083China

The study of modern pollen,and vegetation can improve the accuracy of paleoenvironmental reconstruction based on fossil pollen data.A total of 188 pollen surface samples were collected from Southern Xinjiang(34°00’–43°00’N,74°00’–94°00’E)in China,with an elevation range of 888–4530 *** pollen and vegetation were studied in the northern region of the Kunlun Mountains and the southern region of the Tianshan *** results showed that the surface pollen assemblages on the southern slope of the Tianshan Mountains(3530–1124 m)were divided into three pollen zones,namely,montane steppe,montane desert steppe,and montane *** zones were dominated by Artemisia,Chenopodiaceae,and Ephedra *** surface pollen assemblages in the eastern Pamir Plateau(4530–1287 m)could be divided into alpine meadow,montane desert steppe,and montane desert zones,which were predominantly characterized by Artemisia,Chenopodiaceae,and Asteraceae ***,the Southern Tarim Basin(3548–888 m)comprised montane desert steppe and montane desert zones,which was dominated by Artemisia and Chenopodiaceae *** geographic distribution of the surface pollen sites obtained using ArcGIS,the R-value,and Pearson correlation analyses indicated that the over-represented Picea and Pinus pollen were of external origin and were transported by wind,water(rivers),and ice(glacier movement).Over-representation of Ephedra and Nitraria pollen was mainly distributed in the montane desert and desert steppe zones,*** from Chenopodiaceae and Artemisia were over-represented and broadly distributed across Southern *** pollen was concentrated in areas with walnut trees,strongly indicating the presence of local parent *** to the Hybrid Singleparticle Lagrangian Integrated Trajectory model,more Pinus pollen was transported to the Pamir region by external airflows during spring and summer,resulting in its higher surface pollen *** elucidating t

关键词： Surface pollen Vegetation Distribution Picea Southern Xinjiang

基于主动式Crowbar的双馈风电机组LVRT性能优化分析

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现代电力 2012年第1期29卷 77-81页

作者：孔宪国刘宗歧华北电力大学电气与电子工程学院北京102206

面对短路故障引起的电压大幅跌落,为避免直接脱网对电网造成的不利影响,双馈感应风电(DFIG)机组多采用撬棒保护电路(Crowbar)实现低电压穿越(LVRT)功能。文章利用磁链平衡原理对含Crowbar电路的DFIG三相短路电流简化表达式进行推导,提... 详细信息

面对短路故障引起的电压大幅跌落,为避免直接脱网对电网造成的不利影响,双馈感应风电(DFIG)机组多采用撬棒保护电路(Crowbar)实现低电压穿越(LVRT)功能。文章利用磁链平衡原理对含Crowbar电路的DFIG三相短路电流简化表达式进行推导,提出旁路阻值的优化整定方法。为验证整定方法的有效性及Crowbar退出时间对LVRT性能的影响,利用PSCAD/EMTDC平台对电压骤降情况下DFIG的LVRT性能进行了一系列仿真分析,结果表明:在确保网侧变流器正常工作的前提下,Crowbar阻值在整定范围内取偏大值且Crowbar在故障清除1个周波后退出运行,会使DFIG得到更好的LVRT效果。

关键词：风力发电双馈发电机低电压穿越电网对称故障撬棒保护电路

Optimal scheduling of virtual power plants that ignore the cost of battery loss

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Optimal scheduling of virtual power plants that ignore the c...

第30届中国控制与决策会议

作者： Lu Tianqi Li Zhanjun kong xianguo Yang Jiye Wang Chunsheng Li Jian Yang Xiaozheng Hu Dalong Nan Zhe Jiang Li Liu ran Ma Qiang State Grid Liaoning Electric Power CO LTD.Power Electric Research Institute State Grid Materials CO LTD.

As an emerging management form of distributed energy,virtual power plant（VPP） has experienced booming development worldwide during recent *** optimal scheduling model of VPP without the consideration of battery degradation cost is *** scheduling objective is maximize the expected profit of VPP on condition that the power output limits of Gas turbine generator,security operation constraints of VPP and stable operation constraints of BESS are *** results of simulation show that,compared with the deteminstic approach,this stochastic scheduling method can effectively solve the uncertain problem with renewable energy resources and electricity price and improve economic performace of VPP when trading in electricity market.

关键词： Stochastic optimal scheduling Virtual power plant Energy storage system

来源： cnki会议评论

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影响派出所基础工作开展的问题及对策

河北公安警察职业学院学报 2007年第1期7卷 9-11页

作者：孔宪国王建业元氏县公安局河北元氏051130

公安派出所是集防范、管理、打击服务等多种职能于一体的综合性战斗实体,是整个公安工作的根基。其基础性、战略性地位决定了派出所工作的重要性。而当前在加强派出所基础工作建设上,存在着许多困难和问题,因此,需要我们认真研究并加以... 详细信息

公安派出所是集防范、管理、打击服务等多种职能于一体的综合性战斗实体,是整个公安工作的根基。其基础性、战略性地位决定了派出所工作的重要性。而当前在加强派出所基础工作建设上,存在着许多困难和问题,因此,需要我们认真研究并加以解决。

关键词：公安派出所基础工作问题及对策

Spatial Variation of Dissolved Organic Carbon in Soils of Riparian Wetlands and Responses to Hydro-geomorphologic Changes in Sanjiang Plain, China

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Chinese Geographical Science 2015年第2期25卷 174-183页

作者： XI Min kong Fanlong LYU xianguo JIANG Ming LI Yue College of Chemical and Environmental Engineering Qingdao University Northeast Institute of Geography and Agroecology Chinese Academy of Sciences

Spatial variation of dissolved organic carbon(DOC) in soils of riparian wetlands and responses to hydro-geomorphologic changes in the Sanjiang Plain were analyzed through in situ collecting soil samples in the Naoli River and the Bielahong River. The results showed that the average contents of DOC for soil layer of 0–100 cm were 730.6 mg/kg, 250.9 mg/kg, 423.0 mg/kg and 333.1 mg/kg respectively from riverbed to river terrace along the transverse directions of the Naoli watershed. The content of the soil DOC was the highest in the riverbed, lower in the high floodplain and much lower in the river terrace, and it was the lowest in the low floodplain. The difference in the content and vertical distribution of DOC between the riverbed and the three riparian wetlands was significant, while it was not significant among the low floodplain, the high floodplain and the river terrace. The variability of soil DOC was related to the hydrological connectivity between different landscape position of the riparian wetlands and the adjacent stream. Extremely significant correlations were observed between DOC and total organic carbon(TOC), total iron(TFe), ferrous iron(Fe(II)) whose correlation coefficients were 0.819, –0.544 and –0.709 in riparian wetlands of the Naoli River. With the increase of wetland destruction, soil p H increased and soil DOC content changed. The correlation coefficients between soil DOC and TOC, TFe, Fe(II) also changed into 0.759, –0.686 and –0.575 respectively in the Bielahong River. Under the impact of drainage ditches, the correlations between soil DOC and TFe, Fe(II) were not obvious, while the soil p H was weakly alkaline and was negatively correlated with soil DOC in the previous high floodplain. It indicates that riparian hydro-geomorphology is the main factor that could well explain this spatial variability of soil DOC, and the agricultural environmental hydraulic works like ditching also must be considered.

关键词： dissolved organic carbon(DOC) riparian wetlands spatial variation hydro-geomorphologic changes Sanjiang Plain

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复方阿胶浆对血液系统的作用机制及临床应用

药学研究 2018年第2期37卷 112-114页

作者：李民刘丽张守元孔宪国周艳孙阳恩张路李丽东阿阿胶股份有限公司国家胶类中药工程技术研究中心山东省胶类重点实验室山东聊城252201

复方阿胶浆是由阿胶、红参、熟地黄等中药材组成的复方制剂,具有补气血的功效。该文章综述了近10年复方阿胶浆在血液系统的作用机制及临床应用,为复方阿胶浆的进一步研究提供了依据。

关键词：复方阿胶浆血液系统机制临床应用

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基于电网物资大数据的质量预警系统研究

电力大数据 2018年第9期21卷 42-46页

作者：李凌李屹张敬伟李志新王一哲孔宪国国网物资有限公司北京100120

国网物资有限公司是服务于国家电网有限公司物力集约化管理的专业机构和总部集中招标代理平台。公司以服务物力集约化管理和电网建设为己任,充分发挥自身优势,建立了一套基于电网物资大数据的质量预警系统。该预警系统充分利用科研院所... 详细信息

国网物资有限公司是服务于国家电网有限公司物力集约化管理的专业机构和总部集中招标代理平台。公司以服务物力集约化管理和电网建设为己任,充分发挥自身优势,建立了一套基于电网物资大数据的质量预警系统。该预警系统充分利用科研院所、生产厂家数据资源,通过收集、挖掘电网物资生产厂家信息、原材料市场价格、用工成本、行业合理利润、缺陷等数据,利用大数据思维,从设备生产的"人机料法环"五个环节出发,以主流供应商成本调研数据为基础,构建成本模型、质量缺陷库、平均成本数据库,并采用正态分布分析法,建立了基于一套"红黄绿灯"的预警逻辑的质量预警系统。本文以配电变压器举例说明。

关键词：大数据成本模型质量预警系统配电变压器

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下半膀胱切除术治疗膀胱三角区肿瘤

上海医科大学学报 1998年第2期25卷 131-132页

作者：王忠张元芳丁强孔宪国上海医科大学泌尿外科研究所

目的既切除膀胱三角区及其周围的肿瘤，又保留病人的排尿功能。方法根据Ｗａｌｓｈ前列腺癌根治术加以改进，行膀胱下端包括膀胱三角区及膀胱颈、前列腺、精囊和下端输尿管的下半膀胱切除术。结果为７例病人施行该手术，全部随访６月～... 详细信息

目的既切除膀胱三角区及其周围的肿瘤，又保留病人的排尿功能。方法根据Ｗａｌｓｈ前列腺癌根治术加以改进，行膀胱下端包括膀胱三角区及膀胱颈、前列腺、精囊和下端输尿管的下半膀胱切除术。结果为７例病人施行该手术，全部随访６月～３ａ，效果良好，术后排尿功能正常。结论对位于膀胱颈及三角区的肿瘤，该术式较膀胱全切回肠膀胱术及其他膀胱替代术优越，无严重并发症，术后病人的生活质量好，是一个有价值的术式，但要严格掌握手术适应证。

关键词：膀胱肿瘤膀胱三角区下半膀胱切除术

Influencing factors of colostrum exposure to low-level lead and their relationship with early neural development of infants

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Neural Regeneration Research 2007年第9期2卷 557-560页

作者： Shiguang Li Guoping Wang Kui Fu Chunru Qi xianguo Wu Qinghao kong Yingyi Liang Center for Maternal and Child Health Shanxi Provincial Children＇s Hospital Taiyuan 030013 Shanxi Province China

BACKGROUND： Exposure to low-level lead has a toxic effect on the development of neonates, which has attracted wide attention. Colostrum lead level can be used as the indication of lead exposure. OBJECTIVE： To observe the relationship of colostrum lead level and the neurobehavioral development of infants. DESIGN： A prospective control observation. SETTING： Center for Maternal and Child Health, Shanxi Provincial Children＇s Hospital. PARTICIPANTS： Totally 128 neonates of full-term normal delivery, 76 male and 52 female, from Shanxi Provincial Maternal and Child Health Center and Jiexiu Maternal and Child Health Center were involved in this study. All the involved neonates had no peripartal ischemic/hypoxic history or fetus intrauterine developmental lag. Pregnant women had no various acute and chronic diseases in pregnancy, family history of neurological disease or occupational lead exposure. 128 portions of colostrum sample of full-term normal delivery were collected. Informed consents of detected items were obtained from the puerperants and their relatives. METHODS： ① Experimental grouping： Lead level in the colostrum was determined by atomic absorption spectrometry. According to lead level in the colostrum, the neonates were classified into two exposure groups of greater than or equal to 0.24 μmol/L in a high-level lead group and less than 0.24 μ mol/L in a low-level lead group. ② Experimental evaluation： Mental developmental index （MDI） and psychological developmental index （PDI） of 3-month-old infants were evaluated with Bayley Scales of Infant Development （BSID）. The relationships of MDI, PDI and colostrum lead level were performed correlation regression analysis; The relationship of colostrum lead level and development was performed multi-factor analysis with family environment and health questionnaires. MAIN OUTCOME MEASURES： ① Evaluation results of MDI and PDI. ② Multi-factor analysis results. RESULTS： Totally 128 neonates were involved in the stud

关键词： lead colostrum neural development