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131.
考虑高压油对配流轴所产生的侧倾力矩条件下,进行径向柱塞泵配流轴的平衡性分析.根据配流轴径向受力分析,运用Pro/E和MSC.Patran仿真软件辅助进行配流轴的对称平衡油槽设计.结果表明,配流轴的侧倾力矩直接影响到配流副的正常工作,增大对称平衡油槽的宽度能阻止配流副的摩擦磨损. 相似文献
132.
新钢业采用提钒后的半钢进行耐候窄带钢生产,在炉机不匹配、缺乏精炼手段、轧机能力小、除鳞设施简单和缺少控冷手段的情况下,通过工艺优化、技术改进,将冷弯弯裂、强度偏低、表面麻点等产品缺陷逐一解决,成功试制出符合用户要求和标准的产品。 相似文献
133.
Zhitong Zhao Wenpeng Shan Yunfei Zhang Xiangde Li Jian Ma Yonggang Yan 《应用聚合物科学杂志》2012,125(4):2502-2509
Poly(amino acid)/nano hydroxyapatite (PAA/n-HA) bioactive composite was prepared by in situ melting polymerization. The composition, structure and morphology as well as glass transition temperature (Tg), dynamic mechanical properties of the PAA/n-HA composite were characterized by infrared spectrometer, X-ray diffractometer, X-ray photoelectron spectroscopy, scanning electron microscope, differential scanning calorimeter, and dynamic mechanical analyzer. The results indicated that the n-HA particles were uniformly distributed into PAA matrix and some interactions were found at the interface between PAA and n-HA, and the crystallinity of PAA in the composite decreased with the increase of n-HA content. The Tg and storage modulus of the composite increased with increasing n-HA content, demonstrating that the n-HA content had obvious effects on the crystallization kinetic parameters and thermo properties of the PAA/n-HA composite. In addition, the n-HA amount had evident effects on the degradation of the PAA/n-HA composite in phosphate buffered saline (PBS), and the weight loss ratio of the composite decreased with the increase with n-HA content. The pH value of the medium was stable around 7.40 after the composite immersion into PBS for 8 weeks. © 2012 Wiley Periodicals, Inc. J Appl Polym Sci, 2012 相似文献
134.
135.
Background
Titanium dioxide (TiO2) nanoparticles and fullerene (C60) are two attractive manufactured nanoparticles with great promise in industrial and medical applications. However, little is known about the genotoxic response of TiO2 nanoparticles and C60 in mammalian cells. In the present study, we determined the mutation fractions induced by either TiO2 nanoparticles or C60 in gpt delta transgenic mouse primary embryo fibroblasts (MEF) and identified peroxynitrite anions (ONOO-) as an essential mediator involved in such process. 相似文献136.
本文通过正电子湮没寿命谱分析了ZrO_2材料电导率σ与稳定剂含量的关系,研究表明材料中的“有效空位量”是决定σ的关键因素,解释了σ随稳定剂含量的变化规律 相似文献
137.
Dialectic operator fuzzy logic 总被引:1,自引:0,他引:1
Dialectic operator fuzzy logic (DOFL) is presented which is relevant,paraconsistent and nonmonotonic.DOFL can vividly describe the belief revision in the cognitive process and can infer reasonably well while the knowledge is inconsistent,imprecise or incomplete. 相似文献
138.
本文提出了L集合的概念以及一种新的使用L集合的一阶数据库询问求值方法。因为这种方法对原数据库只增加一个新字句,所以询问求值的效率大为提高,而且因为可以直接使用L集合回答对数据库的询问,求值过程比较简单。 相似文献
139.
Yanliang Zhang Yunfei Chen Changmeng Gong Juekuan Yang Ruiming Qian Yujuan Wang 《Journal of microelectromechanical systems》2007,16(5):1113-1119
The performance of thermoelectric (TE) coolers is determined by the figure of merit of the TE materials ZT. In order to obtain the optimal performance of a superlattice microcooler, both the superlattice structure and the device were optimized in the design and the fabrication process. The thermal conductivities of InGaAs/InGaAsP superlattices with different periodic lengths were measured with the 3omega method. The result indicates that the superlattice at a certain periodic length has minimal thermal conductivity, which, in general, corresponds to an enhanced ZT. A 1D model was utilized to investigate the significant parameters in microcoolers. Based on the modeling results, a set of superlattice microcoolers were fabricated. The maximum cooling temperature that was reached is 0.76degC for the optimized cooler at room temperature. 相似文献
140.
以氯化锂溶液为除湿剂,建立测试翅片式内冷型液体除湿器性能的试验台,分析溶液和空气进口参数对除湿器性能(除湿量和除湿效率)的影响. 相似文献