Results 91 to 100 of about 36,110 (177)
Shuitu Baochi Xuebao目的整地是丘陵山区农业生产中的关键措施，明确整地后土壤属性的变化与田间土壤水分空间变异特征的响应关系，对于提升农业生产效益具有重要意义。方法以广西丘陵山区水平和反坡2种典型整地措施为研究对象，将野外雷达探测试验与室内土壤分析试验相结合，利用图像解析、统计分析等方法，深入探讨整地措施对坡耕地田间土壤水分变异特征的作用。结果在相同外部供水条件下，水平整地后的土壤水分空间变化显著发生在0~30 cm土层，反坡整地集中在20~40 cm土层，坡耕地贯穿整个0~50 cm土层 ...
倪晓庆 +6 more
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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
Rare Metals, Volume 45, Issue 8, August 2026.ABSTRACT Many metallic components are frequently subjected to coupled environments of friction and vibration, stemming from interfacial contact and relative motion between mating parts or external stimuli. Consequently, it is imperative for these components to exhibit a synergy of high wear resistance and superior damping properties.
Ze Pu +12 more
wiley +1 more source
四川大学学报. 自然科学版, 2010 运用切断近似的方法,在有效场框架下,对稀疏晶场作用的键无规Blume-Capel(BC)模型的相变进行了研究.具体分析了三种键无规分布的BC模型.分别探讨了系统三临界点(TCP)随稀疏晶场和键无规这两种无序因子的变化关系及相变曲线呈现的一些新特征,对不同键无规分布的BC模型的相图进行了比较,并给出相应的相图.
朱海霞, 晏世雷
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Multimodal Deep Learning‐Assisted Microstructural Evaluation System for Sintered NdFeB Magnets
Rare Metals, Volume 45, Issue 8, August 2026.ABSTRACT The performance of sintered NdFeB magnets, especially coercivity, is critically determined by their complex microstructure. However, a quantitative microstructural evaluation system (MES) is much needed but has long been missing in the community.
Zihao Wang +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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Ultrasound in Obstetrics &Gynecology, Volume 68, Issue 2, Page 211-219, August 2026.ABSTRACT Objectives First, to evaluate whether the ratio of soluble fms‐like tyrosine kinase‐1 to placental growth factor (sFlt‐1/PlGF) is associated with hemodynamic changes in ophthalmic artery (OA) Doppler in near‐term pregnancy. Second, to assess the performance of OA Doppler to rule in and rule out angiogenic factor imbalance.
M. F. Tinajero +7 more
wiley +1 more source
四川大学学报. 自然科学版, 2009 在q形变费米-狄拉克分布函数的基础上,研究了相对论q形变理想费米气体的低温热力学统计性质,得到了一些重要热力学量例如费米能,基态能,化学势,总能和热容量的解析表达式,揭示了q形变参数和相对论对系统性质的影响.结果表明:q形变导致了一些与正常的系统不同的新奇特性,另外,相对论费米系统的性质与非相对论系统的性质明显不同.
刘慧, 门福殿, 章毛连, 王玉连
doaj
Hypertension at 5 months postpartum in women with gestational diabetes
Ultrasound in Obstetrics &Gynecology, Volume 68, Issue 2, Page 202-210, August 2026.ABSTRACT Objective Gestational diabetes mellitus (GDM) is associated with future maternal cardiovascular disease, independent of the development of Type‐2 diabetes mellitus. As a major cardiovascular risk factor, we examined the incidence and predictors of hypertension at 5 months postpartum in women with previous GDM.
C. Gómez Fernández +7 more
wiley +1 more source
Gaoya dianqi, 2019 以型号为SFPSZ7-150000/220的变压器为例,建立三维三相磁—结构耦合模型,在三相短路的情况下,利用Ansys Maxwell软件进行瞬态电磁场仿真分析,分析绕组的单匝线圈的瞬态轴向力和辐向力,得出了绕组线圈随时间变化的瞬态轴向力和辐向力曲线,并总结了对应的规律:在A、B、C三相的高压绕组当中,位于A相第10分区的单匝线圈所受到的辐向合力为最大;在A、B、C三相的低压绕组当中,位于第7分区的三相绕组线圈中,B相绕组线圈受到的辐向力最小等这些结论。这将为对变压器在短路冲击下的累积效应 ...
李德波 +4 more
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