Results 101 to 110 of about 3,447 (154)

与碳同行 [PDF]

, 2019
将碳元素拟人化,讲述一位足球运动员闯入元素世界,意外接受了传播元素文化的任务,旨在让读者在趣味阅读中了解有关碳单质及含碳化合物的历史和性质。“化学学科拔尖学生培养试验计划 ...
朱亚先, 那行
core  

方波脉冲下聚酰亚胺绝缘破坏机理研究进展

Gaoya dianqi, 2016
变频电机广泛应用于电力牵引以及风力发电。变频器输出的一系列方波脉冲电压有可能导致变频电机绝缘材料过早失效。方波条件下绝缘材料破坏过程、绝缘材料性能的改善成为研究热点。为此,综合国内外研究成果,从局部放电、空间电荷两个方面论述了聚酰亚胺（PI）绝缘破坏的原因,采用扫描电镜（scanning electron microscope,SEM）观察了PI薄膜破坏的微观形貌,并解释了纳米粒子对PI绝缘性能影响机理。最后从目前研究成果出发,介绍了用纳米粒子改善绝缘材料性能 ...
刘洋, 吴广宁, 高国强, 张血琴
doaj  

高梯度真空绝缘子结构的模拟设计

Gaoya dianqi, 2007
HGI是由周期性的导体层和绝缘层装配而成,周期长度、绝缘层与金属层厚度比例的改变都会影响绝缘性能。绝缘材料选定为Kapton,导体材料选定为无锈钢,导体层与绝缘层齐平,利用有限元软件对不同几何结构、不同外电场情况下的电子轨迹进行模拟。电子轨迹的数值模拟计算表明:①设计合理时,HGI中的周期性电场能够抑制电子崩的发展。其中周期长度0.2 mm,厚度比例为5的结构最有可能得到好的绝缘效果;②绝缘层为+45°结构时效果更好;③模拟软件本身有一定的局限性。
屈立辉, 刘列, 吕志辉, 徐启福
doaj  

[Risk factor analysis of excessive resection of facet joint after large-channel spinal endoscopic depression for degenerative lumbar diseases]. [PDF]

Zhongguo Xiu Fu Chong Jian Wai Ke Za Zhi
Yan T, Zeng J, Lin X, Li T, Wu C.
europepmc   +1 more source

[Study on the electric field transmission characteristics of conducted-electrode tumor treating fields]. [PDF]

Sheng Wu Yi Xue Gong Cheng Xue Za Zhi
Liu K, Zhang J, Shi J, Fang H, Li X.
europepmc   +1 more source

[Research progress of tibial tunnel positioning techniques in posterior cruciate ligament reconstruction]. [PDF]

Zhongguo Xiu Fu Chong Jian Wai Ke Za Zhi
Li R, Liao Y, Guo F, Chen Q, Li S, He C.
europepmc   +1 more source

[Management and consideration of positive surgical margins in locally advanced oropharyngeal squamous cell carcinoma treated with oral robotic surgery]. [PDF]

Lin Chuang Er Bi Yan Hou Tou Jing Wai Ke Za Zhi
Hu Y, Zhang X.
europepmc   +1 more source

[The guideline for the diagnosis and treatment of marginal zone lymphoma in China (2025)]. [PDF]

Zhonghua Xue Ye Xue Za Zhi
Hematological Oncology Committee of China Anti-Cancer Association, Lymphoid Disease Group, Chinese Society of Hematology, Chinese Medical Association, Lymphoma Expert Committee of Chinese Society of Clinical Oncology (CSCO), Chinese Workshop of Indolent Lymphomas.   +5 more
europepmc   +1 more source

[Impact of tibial tunnel position in artificial posterior cruciate ligament reconstruction on postoperative knee function and stability]. [PDF]

Zhongguo Xiu Fu Chong Jian Wai Ke Za Zhi
Zhao Y, Wang C.
europepmc   +1 more source

[Florid cemento-osseous dysplasia: A case report]. [PDF]

Beijing Da Xue Xue Bao Yi Xue Ban
Wang Y, Liang Y.
europepmc   +1 more source