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GmbH Germany, part of Springer Nature 2020 Abstract: The state of clean sand was mainly dependent on its void ratio (density) and confining stress that greatly influenced the mechanical behavior... to the enhancement effect of membrane, and it was observed that its influence on the test results was limited. In addition, the experimental results were proved reliable by reproducibility. Key words: void ratio......
Preparation of Fine Spherical Particle Sized Ceria by Precipitation Method with Ammonium Bicarbonate Cui Dali1,Zhang Guocheng1,Zhu Zhaowu1,Zhang Shunli1,Long Zhiqi1 (1.Advanced Materials Co. Ltd., Beijing General Research Institute of Nonferrous Metals, Beijing 100088, China) Abstract:Fine spherical particle sized ceria (CeO2) was prepared by homogeneous precipitation method with ammonium......
型的计算结果如图2所示,表1所示为两者所包含的材料参数的取值. 图2 初始孔隙比对水-土特征曲线的影响及模型计算结果对比[28] Fig. 2 Effect of initial void ratios on soil-water characteristic curves and model calculation compasion[28] 表1 CALLIPOLI模型和本文模型材料参数... against with initial void ratio e0 and suction s 1.4 参数敏感性分析 本节探究材料参数φ,n和m对模型计算结果的影响,假定试样的初始孔隙比e0和参考初始孔隙比er分别为0.93和0.59,其余材料参数见表1. 材料参数φ,n和m对试样的水-土特征曲线的影响如图4所示.由图4可以看出:保持基质吸力不变,增大φ会导致试样的有效饱和度逐渐减小,该影响会随基质......
Fig.13 Relationship between mean area of voids and void content in CFRP 图14 层中孔隙面积的频率分布直方图和概率密度曲线 Fig.14 Statistics histogram and probability density curves of mean areas for intra-laminate voids 图15 孔隙长宽比与孔隙率的关系 Fig.15 Relationship between aspect radio of voids and void content in CFRP 图15所示为孔隙长宽比随孔隙率的变化趋势,采样点由B样条曲线连接,阴影区域标识长宽比的取值范围.对比2种材料中层间孔隙长宽比的最大值,单向带和织物层间孔隙长宽比大于4的分界点分别为pv>1.0%和pv>......
determined according to the treatment effect under different conditions. The results show that the irregularly shaped metal powders are impacted into dense spherical particles, the bulk density and tap density of the metal powders increase noticeably. The combination property of metal powders is improved greatly. Key words: metal powders; particles composite system; spherical particles; powder......
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distribution by height. Water content increases in frozen soil area, and decreases in unfrozen area. Wherever the ice lens body exists, void ratio tends to increase and water content increases substantially...; void ratio; mathematical model 中国的多年冻土面积占国土面积的22.3%,分布较广.冻土区的冻融作用使得构筑物出现裂缝,倾斜,沉陷,结构断裂等现象,给道路和构筑物造成很大的危害.冻土冻胀的机理研究一直是冻土界注重的问题之一[1-3].Harlan[4]根据未冻水动力学原理,提出考虑水分迁移和冰水相变的一维非线性水热耦合方程.该方程可用来求解温度和水分的变化.Konrad......
that the phosphors consist of spherical particles with an average size of about 1 ~ 3 μm.In the crystalline Ca2 Y8 (SiO4)6O2: Eu3+ phosphor, the Eu3+ shows its characteristic emission corresponding to 5 D0 - 7 FJ ( J...; luminescence; europium; spherical phosphor; [全文内容正在添加中] ......
Trans. Nonferrous Met. Soc. China 29(2019) 270-278 Effect of prestressed ultrasonic peen forming parameters on bending curvature and spherical deformation of plate Tao ZHANG1,2, Lei LI1, Shi-hong LU1...) was adopted in order to solve problems of insufficient bending deformation and large spherical deformation of plate during free UPF. The theoretical analysis of prestressed UPF and the influence......
复合材料孔隙含量超声检测系统的设计研究 吴作伦1,宋立军2,蒋志峰1,吴瑞明1 (1.浙江科技学院机械与汽车工程学院,杭州,310023;2.北方设计研究院,石家庄,050011;3.浙江省计量科学研究院,杭州,310013) 摘要:本文结合碳纤维复合材料内部孔隙含量的超声检测理论模型,阐述了计算机控制超声检测系统数据采集和数据处理的原理和实施方法.重点对数字超声卡的操作,时域波形信号的处理,复合材料孔隙率的C扫描成像显示以及直方图分析等关键问题进行分析研究,开发相应的软件应用模块,构建合适的自动化超声检测系统,以满足实际工程中超声检测的要求. 关键词:超声检测; 孔隙率; 复合材料; ultrasonic test; void content; CFRP; [全文内容正在添加中] ......