Results 51 to 60 of about 4,894 (167)
Gaoya dianqi, 2018 综合考虑复合绝缘子在运行中表现出来的各种老化特性,客观评估其老化程度是保障复合绝缘子安全运行的关键。为此,提出一种复合绝缘子的老化评估模型,将复合绝缘子试品的外观检查试验、憎水性试验、红外测温试验结果作为评估模型的输入参数,对复合绝缘子试品进行老化评估,发现2号复合绝缘子老化程度最重,建议退出运行;1号复合绝缘子老化程度最轻;而3号复合绝缘子老化程度一般,需要跟踪监测。最后通过扫描电镜试验和傅里叶红外光谱试验,验证了评估结果的正确性,说明文中提出的评估模型对于复合绝缘子的老化评估具有一定的意义。
胡雯, 赵淳
doaj
Physicochemical and Structural Properties of Wheat Starch-Chlorogenic Acid Complex under Microwave Irradiation [PDF]
To investigate the effects of chlorogenic acid on the physicochemical properties and structural characteristics of wheat starch under microwave conditions, microwave treatment was used to analyze the changes in solubility, swelling, freeze-thaw stability,
Guanghui LI +5 more
core +1 more source
The use of health services by women living homeless in Madrid, Spain
Poverty &Public Policy, Volume 16, Issue 2, Page 172-181, June 2024.Abstract Women living homeless make up a particularly vulnerable and significantly invisible collective, about which there is little information regarding the use of health services. The purpose of this study is to examine the use of health services by a sample of women living homeless in Madrid, Spain (n = 138).
Malena Lenta +3 more
wiley +1 more source
Analyses on nitration in bottom water in marine-cage-cultured area [PDF]
, 2003 根据1998年4月至1999年2月对厦门西海域网箱养殖区底层海水中NH3 N、NO2-的含量变化规律的分析,结合环境因子水温(t)、DO、pH、COD等对发生在养殖底层海水中的氮的硝化作用进行了分析。结果表明,网箱养殖区底层水N的正常代谢偶联,是养殖水体保持稳定的重要条件。Based on monitoring data from Aug.1998～Feb.1999 in marine cultured cage from western Xiamen sea,the variation of NH3N,
李文权, 王宪, 秦爱红
core
Free Iron Determination in Soil by Flame Atomic Absorption Spectrometry [PDF]
Free iron oxide in soil is a product of weathering, migration, and transformation of soil parent materials. Its form, activation, and aging degree can reflect the soil forming process and environment.
Chun YANG +6 more
core +1 more source
Challenging the policy space: The legitimation of alternatives in Chilean pension policy (1980–2019)
Latin American Policy, Volume 15, Issue 2, Page 235-254, June 2024.Abstract In October 2019, Chile experienced its most significant cycle of protests since the return to democracy in 1990; one of the primary demands of this cycle was the improvement of pensions. What effect did the October upheaval have on the Chilean pension policy debate?
Joaquín Rozas‐Bugueño +1 more
wiley +1 more source
Gaoya dianqi, 2018 为研究油浸式变压器中油浸普通牛皮绝缘纸和油浸热稳定绝缘纸的时域介电特性,文中在实验室开展了不同温度下的油纸样品加速热老化试验。通过极化去极化电流法（PDC）获得PDC曲线,根据曲线分析不同类型油纸绝缘在老化过程中的极化特性差异,从PDC曲线中提取电导率并拟合得曲线,探寻能够表征不同类型油纸绝缘老化程度的特征量。结果表明:普通牛皮绝缘纸试样的老化速度快于热稳定绝缘纸,且在老化后期,后者聚合度下降速率变缓更明显;PDC曲线对绝缘材料的变化十分敏感,对于老化时间相同的两种材料 ...
高波 +4 more
doaj
Gaoya dianqi, 2021 为了研究热老化对发电机定子线棒用环氧—云母绝缘频域介电特性的影响,在170℃环境下对线棒样段进行加速热老化试验,老化时间分别为0、7、14、21 d。通过频域介电谱法测试了不同老化时间试样的频域介电谱,分析了老化时间对介质损耗和相对介电常数的影响;采用扫描电子显微镜和傅里叶红外光谱对环氧—云母绝缘体系老化前后的微观形貌和化学结构等理化特性进行表征。结果表明:在老化前期,由于绝缘体系固化交联结构得到加强,极化强度减弱,导致介质损耗和相对介电常数与未老化试样相比有所下降;随着老化时间变长,老化程度增大 ...
杨敏 +5 more
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Lobbying responsiveness to congressional policy agendas
Policy Studies Journal, Volume 52, Issue 1, Page 11-29, February 2024.Abstract We examine the strategic use of contract and in‐house lobbyists by interest groups in response to shifting policy agendas. The role that lobbyists play in the policy process changes based on the policy agenda. Most of the time, subsystems manage small changes to public policy, rewarding actors with long‐term relationships. Organizations with a
E. J. Fagan, Alexander C. Furnas
wiley +1 more source
Gaoya dianqi, 2020 深入开展35 kV干式空心并联电抗器匝间绝缘材料特性分析研究,对35 kV干式空心电抗器制造材料选择、工艺改进和运维方式具有重要意义。为此,文中研究了不同热老化程度和吸湿对电抗器匝间绝缘材料聚酯薄膜介电特性的影响。通过研究发现:不同老化温度（110、130℃）下,干燥的聚酯薄膜相对介电常数、介质损耗正切值和电导率在老化后期（120 d）都呈现增大的趋势。在较高老化温度下,样品介质损耗正切值增加更加明显。不同老化温度下,吸湿对相对介电常数的影响结果不同。在不同老化程度下 ...
周天春, 彭庆军, 姜雄伟
doaj