螺杆分配机头口模出口高度变化对流场的影响

为了研究口模出口高度变化对螺杆分配机头内部流场和挤出均匀性的影响,参数化有限元分析技术贯穿于螺杆分配机头CAE仿真的全过程,采用VISUAL C＋＋和APDL语言开发出专用有限元前处理程序和特殊加载宏,调用ANSYS对螺杆分配机头流道内部流场进行三维有限元模拟与分析。分析结果表明：口模出口高度变小将增加流道内的流动阻力,显著增大狭缝流道内各部分区域过渡截面中间层节点的压力值和口模出口的挤出速度值。当口模出口高度调节较大时,有必要重新调节阻尼块以提高速度分布的均匀性。     

PV的能量意义—压力能

本文赋予PV以压力能的物理意义,给出了严格定义、讨论了其主要性质,并例举了它的一些应用。     

Cellular growth under hydrostatic pressure using bovine aortic EC-SMC co-cultured ePTFE vascular graft

High blood pressure (hypertension) is implicated in the development of atherosclerosis. Blood vessels are constantly subjected to stretch due to blood pressure and changes in stretch usually instigate adaptive vascular remodeling, including abnormal growth and proliferation of vascular smooth muscle cells (VSMCs) as well as extracellular matrix (ECM). In this experiment, we used bovine aortic endothelial cells and smooth muscle cells (EC-SMC) co-cultured ePTFE vascular grafts subjected to normal atmospheric pressure (as a control), and 100 mmHg hydrostatic pressure for 7 d. The increase of cell layer thickness was observed. When measured, the cell layer thickness increased by 116.2%. The increase of collagen (Type IV) synthesis was also observed in the immunohistochemistry assay. When stained with toluidine blue, the cells showed metachromatic phenomenon.     

英国两大政党的决策机制分析——思想库、压力集团和政党领袖对社会政策的影响

英国两大政党的决策机制主要有三大行为者--思想库、压力集团和政党领袖.社会政策的制定会受到不同的思想库、压力集团和政党领袖的影响.本文主要分析了它们在英国社会政策中所起的重要作用.     

三块轴瓦式动压滑动轴承修复与调整

三块轴瓦滑动轴承修复过程中的使用刮削修复方法所需步骤，采用研磨修复方法，所用磨料及研磨方法，轴瓦安装，调整方法及冷状态下预留间隙。     

Research on reasonable winding angle of ribbons of Flat Steel Ribbon Wound Pressure Vessel

INTRODUCTION Axial strength is viewed as the most important parameter in the failure analysis of a pressure vessel. As axial damage is destructive, special attention should be paid to it. The axial strength of an FSRWPV has close relationship with the winding angle α as shown in Fig.1 (Zhu et al., 1995). ASME CODE (1996-1997) stipulates that winding angle of 15°~30° should be used, with nothing said about how the range was determined. In fact, 15°~30° winding angle is not suita…     

对天京变乱责任问题的辩证探讨

1856年9月的天京变乱,谁应负其主要责任,目前史学界说法不一。文学界普遍认为杨秀清逼封万岁,首先激化与洪秀全的矛盾,应承担天京变乱的主要责任,论文对此提出质疑。杨秀清的逼封虽然成为天京变乱的导火线,但在此之后的变乱过程中,他处于被动地位,成为受害者,是矛盾的次要方面,不应对变乱承担主要责任。洪秀全自始至终控制着变乱事态的发展,使变乱按其计划进行,成为变乱的获胜者和最大受益者,是矛盾的主要方面。因此,洪秀全应承担天京变乱的主要责任。     

LabVIEW设计中压力传感器的BP神经网络温度非线形校正

介绍了LabVIEW设计中采用BP神经网络校正压力传感器系统的温度非线性校正的原理和方法,通过计算机仿真与应用,显示了这种方法使压力传感器的性能得到了改善,网络结构简单,准确度高,有实际应用价值。     

压力的成因及其有效管理

压力在生活中无处不在,如果管理得好,压力就能起到积极的作用,帮助你自觉调动自身能量来解决面临的各种挑战;如果管理不好,不仅妨碍你的工作和学习,还会影响身心健康,甚至威胁生命。本文从压力产生的原因、压力的影响以及压力调试等方面,阐述了如何科学有效的管理压力,变压力为动力。     

Study on the nature of pressure signals in a bubbling fluidized bed

In this study on the nature of pressure signals generated by a deterministic or stochastic process in a bubbling fluidized bed, pressure fluctuation measurements were carried out in a 300-mm-diamet column at 0.090 m and 0.40 m above the distributor for different gas velocities. The method of detecting deterministic dynamic underlying pressure signals is proposed on the basis of predictability of pressure fluctuations. The deterministic nature of dynamics in fluidizing system was verified. The deterministic level of dynamics in fluidizing system was analyzed for different locations of pressure measurements and different gas velocities. Project supported by the Science and Engineering Foundation of SINOPEC, China (X599029)