国内汽车起重机用钢丝绳现状

简述汽车起重机的概况,以国内外汽车起重机的部分型号为例,介绍国内汽车起重机用钢丝绳的需求现状。重点介绍提升用钢丝绳、变幅用钢丝绳、伸缩臂用钢丝绳的结构、规格的选用,以期全面提高我国汽车起重机用钢丝绳的使用性能和寿命。     

18×7类不旋转钢丝绳结构特点

指出18×7类不旋转钢丝绳用途的广泛性,通过对18×7类不旋转钢丝绳结构特点的认识,分析钢丝绳的稳定性及产品缺陷,举例说明提高钢丝绳实物质量的措施和行业内急需解决的技术难题。     

Effect of hammer peening on fatigue life of aluminum alloy 2A12-T4

In this study, a series of tests were conducted in aluminum alloy 2A12-T4 to investigate the effect of hammer peening process on the fatigue behavior of holes in specimens. The fracture surfaces of the specimens were observed by means of an optical microscope in order to disclose the mechanism of fatigue failure. The finite element method (FEM) was used to analyze the distribution of residual stress around the holes which were preliminarily treated with hammer peening. The results revealed that the crack of a hammer peened hole always initiated at the peened face. The fatigue life of these hammer peened holes significantly was prolonged five fold compared to non-hammer peened holes. Their fatigue life showed a positive correlation with the residual plastic strain which was induced by hammer peening process. The longest fatigue life was found in cases in which the residual plastic strain surrounded the whole bore of the hole but did not emerge at the fix face.     

论《红豆》中的叙事者如何设障——兼谈《红豆》出现叙事裂痕的原因

从叙事学角度出发,分析叙述者压制潜意识层面的个人话语倾向所采用的手法,从文本层面挖掘叙事出现裂痕的原因.     

Field synergy analysis of laminar forced convection between two parallel penetrable walls

In this paper, some exact solutions for 2-D convective heat transfer between two parallel penetrable walls were derived and analyzed based on field synergy theory. They are valuable to further develop the field synergy principle and understand how to improve or to weaken field synergy in practice. In addition, these solutions can be used as benchmarks to verify numerical solutions and to develop numerical schemes, grid generation methods and so forth. All solutions given in this paper can be proven easily by substituting them into the governing equations.     

Rose-like Cu2O synthesized by assisted PVP K30 hydrothermal method

Rose-like Cu₂O nanoflowers have been synthesized by polyvinylpyrrolidone K30 (PVP K30)-assisted hydrothermal method. Here, copper sulfate CuSO₄ and sodium hydroxide NaOH were used as raw materials. The synthesized Cu₂O powders were characterized by X-ray diffraction (XRD) and field emission scanning electron microscopy (FESEM). XRD pattern exhibited the nanocrystalline nature with cubic structure for the synthesized nanostructures. FESEM images indicated that the rose-like Cu₂O nanostructures are composed of many nearly rectangular shape nanosheets in size of about 1–2 micrometers in width and length and approximate 50–60 nm in thickness. Analysis results reveal that PVP K30 plays a vital role in formation of rose-like Cu₂O nanoflower in this work. The probable formation mechanism of rose-like Cu₂O nanoflower was discussed.     

Response of radiation dosimeters based on in situ oxygen plasma post-treated CVD-diamond thin films to X-ray

Radiation dosimeters based on in situ oxygen plasma post-treated diamond thin films were fabricated in a simple sandwich configuration. Effects of deposition process, methane concentration, and in situ oxygen plasma post-treatment on the sensitivity of the devices to X-ray irradiation were investigated. X-ray response demonstrates that the cyclic deposition process could improve response sensitivity. The increase in methane concentration in the deposition gas mixture will worsen the irradiation response of the devices mainly resulted from the change of the orientation and purity of the films. X-ray photoelectron spectroscopy, photoluminescence, and Raman measurements suggest that in situ oxygen plasma post-treatment can effectively etch non-diamond phases and passivate the silicon-vacancy and nitrogen-vacancy defects of the diamond films, resulting in an increase in the sensitivity of the device by a factor of about 2. Time-dependent response to X-ray indicates that the extended period to achieve photocurrent signals stability for the devices is a limitation for promising applications in radiation dosimetry.     

镓—邻氯苯基萤光酮络合物吸附波研究及应用

本文发现在0.024mol/LHCl、0.02mol/LKCl、3.2×10~(-5)mol/L邻氯苯基萤光酮(O-ClPF)、0.00004％溴化十六烷基三甲铵(CTMAB)体系中,镓在单扫描示波极谱上有一尖锐、清晰、稳定、灵敏的导数极谱波,峰电位为-0.78V(VS·SCE)。镓的浓度在2×10~(-9)—4×10~(-7)g/ml 范围内与导数波高成正比。试验表明,该极谱波属于络合物吸附波。本法已用于测定铝箔、铝丝和铅锌矿中微量镓,结果满意。     

大倾角煤层走向长壁开采顶板岩层活动规律及其矿压控制

依据现场观测和实验室研究的成果，总结了大倾角煤层走向长壁式开采采场矿压显现和顶板岩是活动规律，介绍了工作面矿压控制方法。     

亚变粘区的弹流油膜厚度

本文提出一个线接触等温弹流的完全数值解。作者对Hooke润滑状态图的划分及其膜厚计算公式提出了新的见解:划出一个新的润滑状态区——弹性亚变粘度区并给出相应的油膜厚度计算公式,从而使润滑状态图上各膜厚公式的最大误差由原来的近40%降到6.5%以下,其计算程序有运算速度快,精度高,占内存少,适应范围广的特点。计算中最大Herty压力达2.05 GPa