Results 91 to 100 of about 32,994 (251)
Wear Resistance of Cast Iron Remelted by Non-Transferred Laminar Plasma Jet [PDF]
, 2004 对在大气压条件下用非转移弧层流等离子体射流熔凝强化处理的W-Mo-Cu铸铁表面,采用光学显微镜、显微硬度计、磨损试验机、扫描电镜等,观察和测试了熔凝试样的表面层组织、硬度、耐磨性和磨损形貌.结果表明,熔凝后铸铁表面为初晶渗碳体和莱氏体组成的过共晶组织 ...
潘文霞, 费群星, 马维
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Wildlife Letters, EarlyView.Climate change drives shifts in suitable habitats for Eurasian lynx and its prey (hare, roe deer) in Mohe, Daxing'anling Mountains. Under RCP scenarios, moderate warming (RCP4.5) promotes substantial habitat expansion, while high‐emission conditions (RCP8.5) lead to strong expansion in the 2050s but slower gains and partial contraction by the 2070s ...
Binglian Liu +5 more
wiley +1 more source
Functional Ecology, EarlyView.Read the free Plain Language Summary for this article on the Journal blog. Abstract Plant phenology is crucial for understanding plant growth and climate feedback. It affects canopy structure, surface albedo, and carbon and water fluxes. While the influence of environmental factors on phenology is well‐documented, the role of plant intrinsic factors ...
Yunpeng Luo +8 more
wiley +1 more source
Gaoya dianqi, 2008 笔者应用气相色谱分析技术中的成分超标法I、EC三比值法以及平衡判据法成功地判断出一台主变压器B相内部所存在的突发性电弧放电故障。变压器停运后吊罩检查结果与气相色谱分析诊断结论相吻合,验证了气相色谱分析技术诸方法的正确性及有效性,为大型变压器的运行和异常判断提供了经验。
兰淑丽, 宋昆, 刘芳
doaj
Experimental Measurement of Interdiffusivities and Calculation of Diffusion Kinetics in Some bcc Ti-based Alloys Systems [PDF]
, 2016 钛合金具有比强度高、耐蚀性好、耐热性好及良好的生物相容性等特点，在航空、航天、冶金、汽车及医用等领域得到了广泛的应用。由于钛合金的许多热处理工艺和相变均与合金元素的扩散行为密切相关，因此，有必要对材料的扩散动力学进行实验分析和理论计算。然而，目前由于缺乏相关的扩散实验数据，钛基合金动力学数据库还很不完善。因此，本研究通过扩散偶法，实验测定了部分钛基二元系中bcc相的互扩散系数，并基于文献报道的扩散实验信息和本研究得到的实验数据，利用DICTRA软件进行动力学参数的优化与计算。同时，基于文献报道的实验信息，
罗奕胜
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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
Gaoya dianqi, 2017 为了降低直流系统换相失败的几率,通过对换相机理的分析,得到促进换相的因素,利用模糊控制预防控制换相失败。针对常规模糊控制精度不高,及控制规则与精度间的矛盾,提出了一种基于相平面响应轨迹特征向量法的变论域模糊预防控制方法,从而动态改变论域,修正控制规则,提高控制精度和收敛性。该方法动态监测交流电压的变化和变化率,一旦故障快速增大越前触发角,减小换相面积,抑制换相失败的发生。通过CIGRE HVDC标准模型进行了仿真研究,仿真结果验证了所提控制方法的灵敏性和准确性,能够有效地降低换相失败发生的概率。
胡松伶 +3 more
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Resistive switching property of HfO2 film prepared by atomic layer deposition and its 1D1R device [PDF]
, 2016 随着信息科学与微电子技术的发展，闪存已经成为今天市场上主流的非易失性存储器。但是随着浮栅存储器件尺寸的不断缩小，浮栅耦合、电荷泄漏、单元之间的串扰等问题日益严峻，开发更小尺寸、更低功耗和更高集成度的新型存储单元已成必然趋势。在新型非易失性存储器的研究中，阻变存储器由于结构简单、读写速度快、存储密度高、操作电压低、与CMOS工艺兼容性好等优势有望成为新一代非易失性存储器。本文基于原子层沉积生长的HfO2薄膜，研究了在不同温度下原子层沉积生长HfO2薄膜的阻变特性，确定了最佳工艺温度；在此基础上 ...
陆超
core
Functional Ecology, EarlyView.Read the free Plain Language Summary for this article on the Journal blog. Abstract Forests worldwide are increasingly impacted by drought due to climate change, prompting plants to adapt through dehydration tolerance (DT) and avoidance (DA), two distinct physiological strategies.
Xingyun Liang +11 more
wiley +1 more source
Gaoya dianqi, 2017 准确判断单相接地故障,是馈线自动化关键技术之一。基于时频谱突变原理,提出了一种利用Daubechies db4-db8小波变换提取突变特征量,运用非定项属性决策原则,进行单相接地故障施行判断方法。开发了相应的智能柱上开关;介绍了实际物理模拟试验结果;某山区配电网变电站的现场试运行表明,单相接地故障判断准确性达到100%,验证了该方法的准确性和实用性。
阙波, 陈蕾, 邵学俭
doaj