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101.
The effect of hydrogen heat treatment on impurity contents in aluminum nitride powder of different fineness is studied. Thermodynamic calculations are provided pointing to the possibility of forming gaseous hydrogen compounds with impurity elements. It is established that as a result of treatment the contents of impurity elements, i.e. oxygen, carbon, sulfur, are reduced by a factor of 3-13. The optimum hydrogen heat treatment regime is determined: a temperature of 1323 K and an exposure time of 30 min. 相似文献
102.
Camelia Betianu Florentina A Caliman Maria Gavrilescu Igor Cretescu Corneliu Cojocaru Ioannis Poulios 《Journal of chemical technology and biotechnology (Oxford, Oxfordshire : 1986)》2008,83(11):1454-1465
BACKGROUND: Heterogeneous photocatalysis is influenced by a number of parameters involving synergistic effects; hence, an experimental strategy design that considers interactions between the main variables is needed. The response surface methodology was applied for the investigation of photodegradation of 20 mg L?1 Orange II in aqueous solutions and for optimization of color removal efficiency. Preliminary studies were performed to identify the parameters to be selected for optimization. RESULTS: The input variables considered for experimental design were: solution initial pH, oxidizing agent (H2O2) initial concentration and UV‐A irradiation time. The multivariate experimental design allowed the development of a quadratic response surface model to be used for the prediction of color removal efficiency over the full range of the experimental region. Under the optimum conditions established in the region of experimentation (pH = 6.9, [H2O2]0 = 183 mg L?1 and t = 32 min), a 100% color removal efficiency was obtained in experiments. CONCLUSIONS: It was found that the variables considered have important effects on color removal efficiency. The results demonstrate that the use of experimental design strategy is indispensable for successful investigation and adequate modeling of the process because the interdependence of the reaction parameters cannot be neglected. Copyright © 2008 Society of Chemical Industry 相似文献
103.
文东油田连续气举优化配气数学模型建立及应用 总被引:1,自引:0,他引:1
针对连续气举在开发过程中出现的注入气利用效率低、综合效益差的问题,建立了供气能力有限时的优化配气数学模型,给出了解析法求解过程。文东油田现场试验表明,应用该技术可以实现连续气举井的合理配气,并提高油井产量,适合在油田推广应用。 相似文献
104.
Basem Abdullah & Rula Al-Najdawi 《International Journal of Food Science & Technology》2005,40(5):537-543
Samples of chicken meat from spent laying hens were obtained by four different methods: (1) manual deboning of whole carcasses; (2) manual deboning of skinned carcasses; (3) mechanical deboning of whole carcasses; and (4) mechanical deboning of skinned carcasses. The meat was packaged, frozen and stored at ?18 °C for up to 3 months. Functional properties studied were pH, emulsifying capacity (EC) and water‐holding capacity (WHC) and, in addition, pigment concentration was investigated. Sensory properties included aroma, colour, texture and overall acceptability, as judged by a trained panel using a nine‐point hedonic scale. Removal of the skin prior to deboning by either method gave significantly higher values (P < 0.05) for EC, while WHC values were not significantly different among the experimental treatments, despite higher pH values for mechanically‐deboned meat, with and without skin. Pigment concentrations were highest in meat from Treatment 4 and lowest for Treatment 1, but values for both methods of deboning were affected by the presence of skin. There were no significant differences between treatments for any of the sensory properties studied. Changes occurring in the meat during frozen storage are described. 相似文献
105.
化学模式识别法在钢铁工业中的若干应用 总被引:1,自引:0,他引:1
本文涉及一种崭新的非函数数据处理法及其在工业诊断和优化中的应用。并对其进行要因分析和优化决策的原理作了介绍。结合钢铁工业生产中的实例进行了分析。还探讨了该方法在钢铁工业中应用的意义。 相似文献
106.
This paper describes a method of analyzing the maximum buckling strength of hybrid-fiber multilayer-sandwich cylindrical shells under external lateral pressure with respect to fiber orientations and weighting factors. Formulae for optimizing these parameters are presented and conditions for the application of these formulae are discussed. A discriminant is derived for assessing whether the hybrid sandwich cylindrical shells for given different unidirectional composites should reach the extreme value of critical pressure. 相似文献
107.
Optimal operation of a multibasin reservoir system 总被引:1,自引:0,他引:1
A simulation-optimization procedure is presented for evaluating the extent of interbasin transfer of water in the Peninsular
Indian river system consisting of 15 reservoirs on four river basins. A system-dependent simulation model is developed incorporating
the concept of reservoir zoning to facilitate releases and transfers. The simulation model generates a larger number of solutions
which are then screened by the optimization model. The Box complex nonlinear programming algorithm is used for the optimization.
The performance of the system is evaluated through simulation with the optimal reservoir zones with respect to four indices,
reliability, resiliency, vulnerability and deficit ratio. The results indicate that by operating the system of 15 reservoirs
as a single unit the existing utilization of water may be increased significantly. 相似文献
108.
In the history of operations research in industry there has been an abundance of analyses and recommendations produced in millions of man hours by dedicated OR specialists. And yet the net improvement is significantly lower than expected. There are numerous reasons for this shortfall: incomplete analysis, too much theory, incomplete implementation, unreliable recommendations, or a combination of some of these reasons.
By describing several examples, the major reasons for the fragility of the link between recommendation and implementation will be reviewed. What has to be done today to increase the likelihood of implementing an OR recommendation and thus improve the performance of an industrial entity by using the power of OR tools will then be described. 相似文献
By describing several examples, the major reasons for the fragility of the link between recommendation and implementation will be reviewed. What has to be done today to increase the likelihood of implementing an OR recommendation and thus improve the performance of an industrial entity by using the power of OR tools will then be described. 相似文献
109.
改进的GMDH方法及其在参数预报中的应用 总被引:4,自引:0,他引:4
本文在综合了GMDH方法中几种有效的改进算法的基础上,进一步研究了变量预选及部分表达式的构成问题,采用最优化方法确定变量最佳组成式并进行变量筛选,由此得到精度更高、稳定性较好的模型,将其应用于聚丙烯熔指数的预报,仿真结果令人满意。 相似文献
110.
丙烯酸接枝聚丙烯纤维的结构与性能 总被引:15,自引:2,他引:13
本文研究了用化学引发剂引发丙烯酸接枝聚丙烯纤维的某些影响因素。红外光谱分析表明,丙烯酸接枝在聚丙烯大分子链的叔碳原子上。X-射线衍射和DSC分析指出,纤维接枝后结晶度有所增加,接枝前纤维存在的β-变体转化成了α-变体,接枝纤维的吸湿性、离子交换容量和染色性随接枝率增加而增大。接枝纤维的力学性能有所下降。 相似文献