Results 21 to 30 of about 3,045 (163)
Rare Metals, EarlyView.ABSTRACT Narrowband near‐infrared (NIR) phosphor‐converted light‐emitting diodes (pc‐LEDs) featuring low full‐width at half maximum (FWHM) and high conversion efficiency are crucial for chemical content evaluation, light therapy, and bioimaging.
Chunshen Li +4 more
wiley +1 more source
, 1987 文献[3,4]表述了描述等离子CVD化学反应器流场的数学物理模型,并利用Patankar方法对冷热流场作了求解。本文在此基础上就影响反应器流场、温度场和浓度场的有关参数作了理论研究。所研究的问题有:冷热流场的差别,喷射环缝密度和主流旋转速度对流动的影响。所得结果清楚地表明:这些参数的选择对反应器的性能有着不同程度的影响 ...
朱清文, 赵国英
core
Factors influencing incomplete fusion in automatic girth welding of oil and gas pipelines [PDF]
, 2023 In view of the incomplete fusion occurred in the automatic girth welding of oil and gas pipelines, the factors influencing the incomplete fusion were studied with the welding procedure test and numerical simulation in combination.
Yongli SUI, Zhili LUO
core +1 more source
Rare Metals, EarlyView.ABSTRACT High‐power piezoelectric ceramics which have a wide operating temperature range are essential for sensor and actuator applications in extreme conditions. However, their development is fundamentally hindered by the inherent trade‐off among key parameters (TC, d33, Qm).
Rui Yan +10 more
wiley +1 more source
Gaoya dianqi, 2019 温升是影响油浸式变压器正常运行的重要因素,为了得到变压器的温度场分布,提出一种基于混合方法的多物理场计算方法。对于油浸式变压器流体场和温度场的强耦合问题,混合方法考虑了温度对媒质物性参数的影响,采用迎风有限体积法和迎风有限元法依次计算流体场和温度场,即流体场和温度场依次循环求解,最终得到油浸式变压器启动过程瞬态温度场和稳态温度场。为了验证文中算法的有效性,采用换流变压器二维简化模型,分别采用文中方法和多物理场仿真软件Comsol计算了常温下的稳态温度场,计算结果验证了混合方法的准确性和有效性 ...
刘刚 +4 more
doaj
Functional Ecology, EarlyView.Read the free Plain Language Summary for this article on the Journal blog. Abstract Decomposition is the transformation of dead organic matter into its inorganic constituents. In most biomes, decomposition rates can be accurately predicted with simple mathematical models, but these models have long under‐predicted decomposition in globally extensive ...
Heather L. Throop +8 more
wiley +1 more source
基于无人机红外测试的500kV架空线路在运复合绝缘子温度场特征分析
Dianci bileiqi, 2020 为提升现场复合绝缘子红外测试判定准确率,对现场新投运的123支500 kV复合绝缘子开展基于无人机的红外测试,并提取复合绝缘子温度曲线,统计温差、温度梯度特征,对正常复合绝缘子自身不同部位温度差异的原因进行了讨论,并给出了抑制温度曲线高频干扰的方法。结果表明,现场正常复合绝缘子有相当比例温差超过2 K。正常复合绝缘子温度曲线存在高频变化分量,其来源于伞裙与芯棒之间的温差、红外图像清晰度不足产生的局部温度振荡。通过小波分解与低频分量重构,可有效抑制上述高频分量产生的温差,从而减小现场红外测试结果误判概率。
李特 +6 more
doaj
Zhejiang Daxue xuebao. Lixue ban, 2005 近年来人们在激光冷却和捕获原子方面取得了辉煌的成就，对捕获的冷原子团温度、密度的精确测量也成为一个重要的研究课题.在冷原子温度测量中需要在较短时间内（最长不超过几个毫秒）迅速关断俘获冷原子的磁光阱（包括磁场和光场）.作者针对时间飞行法测量冷原子温度对光场和磁场的关断要求，设计并制作了一种简单、实用的可调脉冲延时和脉宽的脉冲发生器，应用其产生的脉冲在较短时间内有效地关断磁场和光场，达到冷原子温度测量的要求.
WUYan(吴艳) +3 more
doaj +1 more source
Electric Hot Assisted Turning and Its Process Monitoring [PDF]
, 2015 近年来，机械加工行业中出现了大量耐高温、强度高、硬度大的难加工材料。在这些材料的加工过程中，普遍存在着切削力大、刀具磨损严重、表面质量差等问题。用常规的刀具材料和加工方法很难进行切削加工，也达不到现代工业技术的要求。随着历史的发展，人们提出了许多针对这些难加工材料的加工思路和方法，加热切削就是比较好的思路，而导电加热切削则是其中一种行之有效的方法。 本文对现有导电加热切削技术做出了一些研究，提出了通电加热辅助车削的方法，意在探寻这种方法的可行性和效果。通电加热辅助车削是把低压大电流通入到由电源 ...
张天宇
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Success of restoration strategies in preventing extirpation of 2 critically endangered coral species
Conservation Biology, EarlyView.Abstract An unprecedented marine heatwave in 2023 caused widespread coral bleaching and mortality throughout the Caribbean. In the Florida Keys (USA), 2 foundation species, elkhorn coral (Acropora palmata) and staghorn coral (Acropora cervicornis), were severely affected.
Erinn M. Muller +29 more
wiley +1 more source