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141.
西部大开发中的岩石力学与工程地质问题 总被引:2,自引:0,他引:2
刘同有 《岩石力学与工程学报》2003,22(Z2):2541-2541
针对目前西部大开发的一系列基础建设和重点建设项目的相继开工,提出了在西部大开发中的要关注的六个岩土力学与工程地质问题湿陷黄土问题、长年冻土与季节性冻土、滑坡和泥石流、高陡边坡的研究、深埋长隧道工程地质研究、高地应力区深部碎胀蠕变岩体的矿山开采. 相似文献
142.
在对二水石膏脱水速度试验及其传统热加工设备传热慢、热耗高、产量低原因分析的基础上,本文提出了一种新型建筑石膏粉加工设备,并详尽说明了其工作原理传热过程及其它有关性能。该设备方案属于国内首创。 相似文献
143.
144.
1.概况(见区域位置图)
鹿回头半岛位于海南省三亚市,半岛至三亚凤凰国际机场距离为20km左右,约20分钟车程,至市区距离则为3km左右,半岛西面为三亚湾,东面为小东海,面面为鹿回头公园,北面为南山岭,占据三亚市内独特的地理位置,具有得天独厚的风景资源,与市区交流联系便捷。 相似文献
145.
146.
Pengfei Liu Lars R. Jensen Chengwei Gao Morten M. Smedskjaer 《Journal of the American Ceramic Society》2022,105(2):1039-1051
Aluminoborate glasses have recently been found to feature high resistance to crack initiation during indentation due to a highly flexible network structure. In cesium aluminoborate glasses, it has been found that the use of a simple post-treatment, namely aging in a humid atmosphere, can further improve this resistance. To better understand the mechanical properties of this glass family upon humid aging, we here study the effect of aging conditions on the structure and mechanical properties of Li,K,Cs-aluminoborate glasses. As expected, we find that higher humidity and longer aging time cause more pronounced permeation of atmospheric water into the glasses. Due to their denser structure and stronger modifier-oxygen bonds, the humid aging has a relatively smaller effect on the mechanical properties of Li- and K-containing glasses relative to Cs-containing glasses, with the latter achieving an ultrahigh crack resistance. We find that the humid aging leads to the formation of a hydration layer in the Cs-aluminoborate glass surface, with a thickness of around 26 μm upon aging at 23 °C with 40% relative humidity for 7 days. Moreover, a remarkable indentation behavior, that is, the observation of μm-sized shear bands inside the imprint of the Cs-glass upon aging at 60% relative humidity is reported. Taken as a whole, the work provides guidelines for how to control the humid aging rate as a function of relative humidity and temperature to form a hydration layer and thus achieve improved crack resistance in such glasses. 相似文献
147.
Abas Asim Omer Altyeb Ali Abaker Wei lan Lu Qingyou 《Journal of Applied Electrochemistry》2022,52(5):813-820
Journal of Applied Electrochemistry - There has been a growing interest in the performance of supercapacitors (SCs) based on Transition Metal Oxides (TMOs). It has recently been included in... 相似文献
148.
Zhu Xuefang He Meng Xiao Ling Liu Haozhuo Hu Mancheng Li Shuni Zhai Quanguo Chen Yu Jiang Yucheng 《Journal of Applied Electrochemistry》2022,52(6):979-987
Journal of Applied Electrochemistry - A novel nitrite electrochemical biosensor is constructed by glassy carbon electrodes (GC) coated by chloroperoxidase (CPO) -Au nanoparticles-MoS2 nanoflowers... 相似文献
149.
Chien-Sheng Liu Yu-An Li 《The International Journal of Advanced Manufacturing Technology》2018,99(5-8):1109-1117
In the industrial manufacturing field, machining is a major process. Machining operations involve grinding, drilling, milling, turning, pressing, molding, and so on. Among these operations, grinding is the most precise and complicated process. The surface condition of the grinding wheel plays an important role in grinding performance, and the identification of grinding wheel loading phenomena during the grinding process is critical. Accordingly, this present study describes a measurement method based on the acoustic emission (AE) technique to characterize the loading phenomena of a Si2O3 grinding wheel for the grinding mass production process. The proposed measurement method combines the process-integrated measurement of AE signals, offline digital image processing, and surface roughness measurement of the ground workpieces for the evaluation of grinding wheel loading phenomena. The experimental results show that the proposed measurement method provides a quantitative index from the AE signals to evaluate the grinding wheel loading phenomena online for the grinding mass production process, and this quantitative index is determined via some experiments in advance in the same grinding environment to help the monitoring and controlling of the grinding process. 相似文献
150.
Minireview: Methodology and instrumentation to evaluate critical pressure and temperature parameters
Critical parameters, such as critical temperatures, pressures, and densities, are basic in the development of supercritical fluid technology. However, the number of compounds for which critical parameters has been determined and has been limited by the current technology and the sensitivity of compound information to the external environment in a critical state. This paper provides an overview of the principles, key equipment, and methodologies to measure the critical parameters of compounds. The reliability of various determination methods is discussed, and future research into methods to determine critical compound parameters is suggested. 相似文献