Results 41 to 50 of about 36,289 (215)
通过测试所得到的结果显示,使用耦合支护以及找到关键的部位来进行支护是非常有必要的一项任务。这也在另一个角度上进行了一个非常有效的控制手段。对此,论文针对煤矿高地应力软岩巷道支护技术现场试验进行一系列的分析。
晓雷 陈
semanticscholar +1 more source
ABSTRACT Background Identification of offending foods in dogs with adverse food reactions is usually based on “deterioration” during open food challenges. Objectives To examine the placebo effect during double‐blinded, placebo‐controlled food challenges using a predefined set of criteria for relapse.
Evi I. Sofou +4 more
wiley +1 more source
提出了声发射法检测绝缘子放电的方案,试验研究了该方案的可行性及不同放电形式的识别问题。具体内容包括试验装置、试验方法和试验结果,在大量试验的基础上,分别研究和总结了绝缘子内部放电、表面污秽放电和电晕放电时声发射波的特征,研究了声发射检测中的干扰和抗干扰措施。
王成江 +4 more
doaj
Wear Resistance of Cast Iron Remelted by Non-Transferred Laminar Plasma Jet [PDF]
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
core
ABSTRACT NiFe‐based MIL‐55 metal‐organic frameworks (MOFs) face challenges in achieving atomically precise composition and reliable methods for uniform growth. This study addresses these challenges by applying a slow evaporation crystallization technique to crude colloidal MIL‐55 products from hydrothermal synthesis, resulting in highly uniform ...
H. R. Haris +10 more
wiley +1 more source
Research on the influence of seepage on the mechanical behavior and slope stability of granite residual soil [PDF]
花岗岩残积土在我国东南沿海地区广泛分布,是很多工程构筑物的组成材料、地基或地层环境介质。渗流会对土体产生力学、物理和化学方面的作用,从而导致土体力学特性变化,影响边坡稳定性。因此研究渗流对花岗岩残积土的力学特性及边坡稳定性影响具有重要的理论和现实意义。 本文在总结分析土体力学特性、渗透特性和渗流对土体力学特性及边坡稳定性影响研究发展概况的基础上,利用土工基础试验仪器和三轴渗流剪切试验仪,借助有限元分析软件,进行了以下几方面的工作: (1)测试分析了花岗岩残积土试样含水率、比重、颗粒组成 ...
李祥华
core
ABSTRACT Achieving a simultaneous enhancement of strength and ductility remains a critical bottleneck for the large‐scale and cost‐effective engineering application of magnesium alloys. In this work, guided by first‐principles calculations, we tailored the τ‐Mg32(Al,Zn)49 phase and optimised twin boundary, thereby designing and successfully ...
Yun‐Xuan Zhou +8 more
wiley +1 more source
为了降低污闪事故的威胁、了解绝缘子积污机理,研究人员在绝缘子积污特性方面做了许多工作,但仍少有针对均匀电场下的绝缘子积污特性的深入研究。为了研究均匀电场下绝缘子的积污特性,研制了一种用于均匀电场下人工积污试验的装置,该装置由恒温恒湿箱、无风试验罐以及粉尘发生器组成,使用多个测量装置监控试验区内的环境参数,并设计了相应的试验方法,按负反馈逻辑控制试验区内的环境参数。通过仿真计算与实际测量的手段对装置和方法的有效性做了初步研究,研究结果表明,该装置不仅能提供不同电压种类、场强可控的均匀电场 ...
梅红伟 +4 more
doaj
Acoustic Emission Warning Signals Change Law Research during Deformation and Failure of Gassy Coal Rock [PDF]
为提高矿井瓦斯突出灾害预测准确率,基于力学、声学理论,采用实验室试验方法,以标准煤试样为研究对象,对含瓦斯煤岩变形破裂过程声发射(AE)预警声信号变化规律进行研究。试验结果表明:围岩应力增大,煤岩破裂由低围岩应力的脆性破坏逐渐过渡到高围岩应力状态的塑性破坏,可根据声发射高幅信号提前预测煤岩破裂时刻。瓦斯的力学和非力学作用对煤岩体力学性质和变形特性的影响均随瓦斯压力的增加而变大。瓦斯压力越大,则煤岩破裂进程加快,积累的声发射能量迅速释放,高值振铃计数声发射信号覆盖时间区段变长 ...
吕祥锋 +5 more
core
Experimental Study on Performances of Heat Pump Water Heater Based on Heat Recovery of Domestic Wastewater [PDF]
In order to solve the present situation of unceasing demand for hot water and severe loss of quantity of heat from wastewater,a new type of heat pump water heater was developed based on heat recovery of domestic wastewater.In this paper,the relation ...
core +1 more source

