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温湿度对开关柜局部放电物理信号影响研究

Gaoya dianqi
局部放电是开关柜发生绝缘故障的主要原因和前期阶段，准确有效地对局部放电产生的特征信号进行监测和分析是保障设备安全运行的关键。针对广泛运用的超声波和地电波检测法在实际检测过程中忽略的环境温湿度因素，本文设计制作了四种典型绝缘缺陷模型，在不同温湿度条件下测量局部放电信号并进行汇总分析，研究了环境温湿度对不同类型局部放电起始和熄灭电压以及超声波与地电波信号的影响特征。结果表明，温度升高针板缺陷超声波信号和悬浮缺陷地电波信号增强，40-60℃时针板缺陷熄灭电压与沿面、悬浮和气隙缺陷起始熄灭电压下降明显 ...
蔡乐辉, 曾潮旭, 杨森, 杨淳岚, 杨龙山, 陈天翔   +5 more
doaj  

[Impact of ultrasonic scaling on abutment screw torque in implant restorations]. [PDF]

Beijing Da Xue Xue Bao Yi Xue Ban
Tang Y, Zhao X, Yang X, Jia H, Liu Y.
europepmc   +1 more source

基于超声导波的钢管杆件损伤探测模拟

Jianzhu Gangjiegou Jinzhan
为研究网架结构中钢管杆件损伤缺陷检测的问题，选择在杆端施加位移的方式进行有限元分析。考虑超声导波需要具有在特定频率范围内不发生频散的特征，选择L（0，2）模态超声导波开展无损检测。分析了适用于钢管无损检测的导波信号频率和信号周期特征，利用L（0，2）模态超声导波进行了不同圆周夹角的周向缺陷和不同长度轴向缺陷的导波检测。有限元分析结果表明，考虑多模态叠加和最大反射率的影响，频率为70 kHz周期为10的Hanning正弦信号激励的超声导波适用于钢管杆件的缺陷检测；当钢管缺陷宽度与深度不变时 ...
曹栋, 顾征宇, 潘钻峰, 王皓, 杨毅超   +4 more
doaj  

[Molecularly imprinted polymers： novel green preparation methods and cutting-edge applications review]. [PDF]

Se Pu
Li F, Jia B, Hu Q, He X, Chen L, Zhang Y.   +5 more
europepmc   +1 more source

[Hereditary erythrocytosis caused by a novel EGLN1 gene mutation: a case report]. [PDF]

Zhonghua Xue Ye Xue Za Zhi
Zhang QG, Fu WJ, Ling C, Bao WW, Zhao CZ, Jin QC.   +5 more
europepmc   +1 more source

[Rapid determination of lubabegron residues in animal-derived foods by ultra performance liquid chromatography- tandem mass spectrometry]. [PDF]

Se Pu
Yang C, Zhu WX, Liu YF, Zhang HW, Wei W, Hu K.   +5 more
europepmc   +1 more source

[Clinical practice guideline for point-of-care ultrasound-guided peripherally inserted central catheter placement in neonates (2026)]. [PDF]

Zhongguo Dang Dai Er Ke Za Zhi
Asia-Pacific Health Association Pediatric Medicine Branch, Asian-European Research Society for Pediatric and Neonatal Critical Ultrasound, Beijing Association of Holistic Integrative Medicine Neonatal Critical Care Medicine Branch, Editorial Board of Chinese Journal of Contemporary Pediatrics.   +3 more
europepmc   +1 more source

[Predictive value of a multimodal radiomics model for central lymph node metastasis in clinically node-negative papillary thyroid microcarcinoma based on machine learning]. [PDF]

Zhejiang Da Xue Xue Bao Yi Xue Ban
Feng J, Yang Y, Liu S, Qin A, Ye J, Jiang Y.   +5 more
europepmc   +1 more source

[Infrared thermography-assisted design and harvesting of ultrathin anterolateral thigh perforator flaps]. [PDF]

Zhongguo Xiu Fu Chong Jian Wai Ke Za Zhi
Zhang C, Pan J, Yin S, Shao G, Zhou X, Yu G, Wu L, Wang X.   +7 more
europepmc   +1 more source

[Association between insulin resistance and idiopathic central precocious puberty in girls and the diagnostic value of insulin resistance]. [PDF]

Zhongguo Dang Dai Er Ke Za Zhi
Li JB, Xiao Y, Jiang SQ, Luo XY, Zhang HR, Sun J, Shi WH, Yang Y, Wang W.   +8 more
europepmc   +1 more source