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81.
本文研制的电脑测试仪旨在解决运动员心理选材和心理训练问题,能完成反应时动作灵敏度、动作协调性、视觉注意力、记忆力、时间知觉、闪光融合值、心理耐久能力和抗干扰能力等心理指标的测试。 相似文献
82.
为解决主轴系统刀尖点频响函数预测中的主轴系统子结构划分问题,并提高各子结构建模的精确性,提出基于等转动惯量法对主轴系统中的夹头进行等效建模,基于等平均惯性矩的方法对铣刀的刀齿段和过渡段进行精确建模,以VMC850E主轴系统为研究对象,通过响应耦合子结构法建立主轴系统刀柄—夹头—刀具结合面等效模型,以刀尖点频响函数实验值... 相似文献
83.
利用OM、SEM、EDS、EBSD等技术观察和分析二次再结晶中断抽出试样的组织和取向.结果表明:高温退火保温时间达到5 h时,部分晶粒发生了二次再结晶,随着二次再结晶持续时间的延长,发生二次再结晶晶粒的数量显著增多,达到25 h时基本形成了完全的二次再结晶组织.Goss织构随保温时间的延长逐渐增多,而{111}〈112〉织构和{411}〈148〉织构含量显著降低,Goss织构含量在退火保温25 h时达到91.1%,其强度达到284.771;抑制剂随高温退火时间的延长逐渐粗化,其对晶界的钉扎逐渐减弱直到完全失去抑制作用. 相似文献
84.
质量成本的概念是由美国质量专家A.V.菲根堡姆在20世纪50年代提出的.他将企业中质量预防和鉴定成本费用与产品质量不符合企业自身和顾客要求所造成的损失一并考虑,形成质量报告,为企业高层管理者了解质量问题对企业经济效益的影响、进行质量管理决策提供重要依据.…… 相似文献
85.
介绍了一种使用预燃室煤粉烧嘴的新型烧结点火保温炉的研制与设计,该点火保温炉与24m^2环型烧结机配用,能做到点火时间短,点火质量高和大幅度节药能源。 相似文献
86.
Jingyun Gao Qing Zhao Yanghui Sun Guo Li Jingmin Zhang Dapeng Yu 《Nanoscale research letters》2011,6(1):45-6
We developed a novel approach to synthesize phosphorus (P)-doped ZnO nanowires by directly decomposing zinc phosphate powder.
The samples were demonstrated to be P-doped ZnO nanowires by using scanning electron microscopy, high-resolution transmission
electron microscopy, X-ray diffraction spectra, X-ray photoelectron spectroscopy, energy dispersive spectrum, Raman spectra
and photoluminescence measurements. The chemical state of P was investigated by electron energy loss spectroscopy (EELS) analyses
in individual ZnO nanowires. P was found to substitute at oxygen sites (PO), with the presence of anti-site P on Zn sites (PZn). P-doped ZnO nanowires were high resistance and the related P-doping mechanism was discussed by combining EELS results with
electrical measurements, structure characterization and photoluminescence measurements. Our method provides an efficient way
of synthesizing P-doped ZnO nanowires and the results help to understand the P-doping mechanism. 相似文献
87.
There are four primary classes of natural gas hydrate deposits in natural world. The differences between them are in the distribution of the methane hydrate, free gas, and free water layers. A reactor which the height was 120 mm and the inner diameter was 103 mm was used in hydrate formation and dissociation, and 17 thermocouples measured the distribution of temperature during the mining process. Different experimental means were applied to simulate three classes of methane hydrate deposits, in which water and glass beads filled in different orders. The hydrate samples were dissociated by depressurization, and the results showed no need to test a backpressure greater than 94% of the equilibrium pressure of methane hydrate. Class 1 sample's methane hydrate decomposition rate was slower than that of class 3 sample at the beginning of depressurization when backpressure was 2.3 and 2.6 MPa, but then, the opposite happened. The average dissociation rate decreased nearly linearly with the increase in backpressure for the class 1 samples. 相似文献
88.
Yanghui Li Hui Zhou Xiaoyu Liu Chengliang Xia Le Wang 《Journal of Modern Optics》2018,65(12):1424-1430
Due to its spectral transmission/reflection properties, dichroic mirror (DM) is widely applied in nearly all microscopes to separate and combine beams with diverse wavelengths. However, its potential distortion effects to the point-spread function (PSF) have been ignored to a large extent. Here, we built a mathematical model to quantify these effects. Specifically, we focus on STED microscopy, whose performance is extremely sensitive to the systematic deficiencies. Both excitation and depletion beams are analysed, and the peak intensity and the shape of the effective PSF are calculated accordingly. More importantly, the strategy to compensate the DM-induced PSF distortion is also given in this paper. 相似文献
89.
利用DSP芯片TMS32LF2407的CAN控制器模块开发了基于CAN总线的电缆蠕变量测试系统,整个系统具有较高的可靠性和可扩张性,且有实际应用价值。 相似文献
90.