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11.
研究得到熔盐混合物表面张力的群论模型参数随温度的变化规律,按此规律可推算任一温度下熔盐混合物全组成范围内的表面张力,用12个物系600个数据点检验,总平均相对误差为0.62%。  相似文献   
12.
Lee CC  Chen HC  Jaing CC 《Applied optics》2006,45(13):3091-3096
Titanium oxide films were prepared by ion-beam-assisted deposition on glass substrates at various substrate temperatures. The effect of the temperature of thermal annealing from 100 degrees C to 300 degrees C on the optical properties and residual stress was investigated. The influence on the stoichiometry and residual stress of titanium oxides deposited at different substrate temperature was discussed. The residual-stress was minimum and the extinction coefficient was maximum at an annealing temperature of 200 degrees C with a substrate temperature of 150 degrees C. However, when the substrate temperature was increased to 200 degrees C and 250 degrees C, the residual stress was minimum and the extinction coefficient was maximum at an annealing temperature of 250 degrees C. The spectra of x-ray photoelectron spectroscopy reveal that the films lost oxygen and slowly generated lower suboxides at the annealing temperature at which the residual stress was minimum and the extinction coefficient was maximum. As the annealing temperature increased above the temperature at minimum stress, the lower suboxides began to capture oxygen and form stable oxides. TiO2 films deposited at substrate temperatures of 200 degrees C and 250 degrees C were more stable than films deposited at 150 degrees C.  相似文献   
13.
在保证路基施工质量的前提下,对重塑红黏土在小应变幅值条件下土体动剪切模量和阻尼比的研究,可作为其是否适宜作高铁地基的判别标准之一.为此,在颗分、液塑限及击实等试验的基础上,对不同围压下标准红黏土试样进行小应变幅值的共振柱试验研究.通过对相关试验数据进行整理,得出了重塑红黏土在小应变条件下动剪切模量和阻尼比的变化规律及其影响因素.利用改进的Davidenkov模型对重塑红黏土动力指标进行了拟合,效果良好.该研究成果可为相关高速铁路路基工程提供基础数据及分析参考.  相似文献   
14.
为了探索新型高灵敏度光电拾音器技术方案,基于光学隧穿效应研究,将声压变化转换为全反射棱镜中全反射面与摆片光学面之间的光学隧穿距离变化,从而改变光束在棱镜全反面处的反射(透射)损耗,通过直接测量反射(透射)光的功率变化,实现拾音器基本功能。利用半导体激光器和直角全反射棱镜搭建了一套简易的原理验证实验系统,并利用该系统对三角波信号驱动进行了实验。结果表明,反射光功率会随着三角波信号的改变而改变,光功率改变达到5.6%;由声音引起的玻璃振膜距离变化也可改变输出光功率,并被检测出来。初步验证了该方案的可行性。  相似文献   
15.
In this paper, we consider the two-machine open-shop scheduling problem with rejection. The objective is to minimize the sum of the makespan of accepted jobs and the total rejection cost of rejected jobs. We show that the problem is NP-hard even in three special cases and then provide a pseudo-polynomial time algorithm for this problem, which means that the problem is actually NP-hard in the ordinary sense. This answers an open problem posed by Shabtay et al. in (J Schedul 16:3–28, 2013). Finally, a 2-approximation algorithm and an FPTAS are designed for the problem.  相似文献   
16.
Abstract

This paper reports on the application of a phase shifting interferometry technique for the concurrent measurement of the thermal expansion coefficient αf and the elastic modulus Ef /1 - Vf of Ta2O5 thin film. The Ta2O5 films were prepared by ion beam sputter deposition. The stresses in the thin films were measured with the phase shifting interferometry technique using two types of circular discs with known thermal expansion coefficients, Young's moduli and Poisson's ratios. The temperature-dependent stress behaviour of Ta2O5 films was obtained by heating samples in the range from room temperature to 70°C. The internal stresses of Ta2O5 thin films deposited on the BK-7 and Pyrex glass substrates were plotted against the stress measurement temperature, showing a linear dependence. From the slopes of the two lines in the stress versus temperature plot, the thermal expansion coefficient and the elastic modulus of Ta2O5 thin film are then calculated.  相似文献   
17.
红磷化工有限责任公司 1989年从国外引进NorskHydro(诺斯克黑特罗 )公司半水二水再结晶浓缩工艺生产湿法磷酸 ,装置自 1993年 5月投产以来 ,一直处于摸索、改进状态。介绍半水二水装置流程及主要设备规格 ;在工艺设备管道材质方面的技改情况 ;对系统堵塞的冲洗办法 ;设计与优化后工艺指标的对比。通过 9年的探索、技术改造 ,生产量已达 78kt/aP2 O5(设计能力 6 0kt/a) ,技术经济指标改善 ,获得较好的经济效益 ,并提出目前尚存在的问题  相似文献   
18.
Tang CJ  Jaing CC  Lee KS  Lee CC 《Applied optics》2008,47(13):C167-C171
Ta-Si oxide composite thin-film rugate filters were prepared by radio frequency ion-beam sputtering and their residual stress and substrate deflections were measured. The residual stress and substrate deflection of these composite film rugate filters were less than that of notch filters made from a series of discrete quarter-wave layers with alternate high and low indices because of the smooth modulation of composition and no interface structure of the rugate filter.  相似文献   
19.
Lee CC  Chen HC  Jaing CC 《Applied optics》2005,44(15):2996-3000
The effects of thermal annealing of titanium oxide films deposited by ion-beam assistance at annealing temperatures from 100 degrees C to 300 degrees C on the residual stress and optical properties of the films was investigated. The refractive indices and extinction coefficients increased gradually as the temperature was increased from 100 degrees C to 200 degrees C and then declined gradually as the temperature was increased further from 200 degrees C to 300 degrees C. The film lost oxygen and slowly generated lower suboxides as the annealing temperature was reduced below 200 degrees C, as determined by x-ray photoelectron spectroscopy (XPS). As the annealing temperature increased above 200 degrees C, the lower suboxides began to capture oxygen and form stable oxides. XPS measurements were made to verify both the binding energy associated with the Ti 2p line and the variation of the O 1s line. A Twyman-Green interferometer was employed for phase-shift interferometry to study the residual stress. The residual stress declined as the temperature was reduced from 100 degrees C to 200 degrees C because the lower suboxides reduced the stress in the film. Above 200 degrees C, the film began to capture oxygen, so the residual stress rose. At 300 degrees C, the film was no longer amorphous as the anatase was observed by x-ray diffraction.  相似文献   
20.
We consider the bounded single-machine parallel-batch scheduling problem with release dates and rejection. A job is either rejected, in which case a certain penalty has to be paid, or accepted and then processed on the machine. The objective is to minimize the sum of the makespan of the accepted jobs and the total penalty of the rejected jobs. When the jobs have identical release dates, we present a polynomial-time algorithm. When the jobs have a constant number of release dates, we give a pseudo-polynomial-time algorithm. For the general problem, we provide a 2-approximation algorithm and a polynomial-time approximation scheme.  相似文献   
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