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41.
酶解工艺参数不仅会影响畜禽骨蛋白的酶解效率,而且会改变骨胶原肽产物的肽分子量分布、氨基酸组成和微结构性能,从而影响其高值高效化利用。以制备均一性低分子量骨胶原肽为目的,以牛骨粉为研究对象,以水解度为主要评价指标,考察碱性蛋白酶、中性蛋白酶、复合蛋白酶和风味蛋白酶对牛骨粉的酶解效果,探究双酶分步酶解工艺、脂肪酶预处理的单独与组合应用对酶解效果的提升作用,选定最优的低分子量骨胶原肽制备工艺;结合酶解过程中各项指标的变化、产物表征分析和Person相关系数法分析不同复合酶解工艺对产物特性的影响及作用机制。研究发现:经脂肪酶预处理-碱性蛋白酶-复合蛋白酶酶解工艺制备的骨胶原肽产物具有最佳的理化性质,优化的工艺参数为:底物质量浓度为0.09 g/mL、初始pH值7.5的牛骨粉溶液加入碱性脂肪酶(加酶量0.08%)在40℃下反应4 h,再加入碱性蛋白酶(加酶量0.36 U/g)在60℃下反应5 h后,最后加入复合蛋白酶(加酶量0.36 U/g)在55℃下反应5 h,此时,水解度可达16.12%,总游离氨基酸含量可达171.571 mg/g,其Mw、Mw/... 相似文献
42.
Wang Jianping Mi Linshu Chen Gang 《保鲜与加工》1993,(6):32-37
The angular frequency and decaying constant of each copmonect for the
transient waveform in power systems were obtained by using the discrete Fourier transform; the amplitude and phase angle were calculated in the linear curve fitting method. And all of the parameters obtained above were treated in an unified optimization by using the curve fitting optimization of the least square method of general nonlinear funcrion so as to get the results of waveform analysis. Two examples are included. 相似文献
43.
Luxikou River is one of shallow waterway in middle reach of Yangtze River.The navigational channal changes with the fluvial process of river. In the meanwhile,the shoals exist at the entrance of Zhigang and Zhonggang branch. It's difficult to maintain the waterway. The depth of waterway is kept upon 3.2 meters,and the carrying capacity of tank barge must be decreaed to pass through.For the demands of constructing the main channel of Yangtze River,the measements for stabilizing and improving must be carried out as soon as possible. 相似文献
44.
Many cities are planning to build up the lightrail in order to solve their traffic jam.We try to find a function to describe the going-out cost and analyse the character of this function.The conclusion can be reached that lighrail can make aggregation and spreading effect on the economic activity in the district along the lightrail transit line because the change of cost brought by the lightrail traffic system lead to redistribution of the product region. Synthetically considering factors which can impact this aggregation and spreading, via applying the method of AHP, we set up an evaluation system which can be used to measure the economic effect brought by the lighrail. 相似文献
45.
Based on the analysis of the status of building construction in China, the development of Assembled Structure System (ASS) can solve not only the problems in construction, but also is the key for realization of building industrialization. On the basis of technique innovations, a study on the structural performance, construction method and precast production of ASS should be carried out to inherit the old one and overcome its demerits. The process reengineering should be done in the construction enterprise to promote the development of building industrialization. 相似文献
46.
TAN Wen-an 《保鲜与加工》2004,(12):73-77
By analyzing the process of enterprise information engineering construction and intra relationship among information system requirement, business process modeling, application system constructing and project management, one of 4 meta model composed of requirement engineering, process engineering, application system engineering and support engineering is proposed for enterprise information engineering. The developments and applications of the business processes and its application systems are integrated into the same development space and application space. Basing on this, a prototype system composed of requirement modeling environment, business process modeling environment, application system modeling environment, and support engineering environment has been designed and built, which is used for supporting enterprise information engineering constructing. It is valued for the enterprise information engineering construction in our country. 相似文献
47.
Based on experience in customer service evaluation,through the analysis of many factors affecting customer satisfaction calculation estimate, customer service evaluation rules as well as customer-oriented and supply chain partner-oriented methods are developed and discussed from the view of supply chain, besides, we construct two sets of customer satisfaction evaluation systems, in which we perform non-dimensional analysis on evaluation system to form single factor evaluation matrix after using improved AHP to determine each factor item's weighting ,utilizing fuzzy decision theory to construct evaluation model for integrated estimate. This evaluation method is scientific, round and objective with more stability and convienience in practical use. 相似文献
48.
Asymmetric wall products are widely used in the engineering. However, there are many limitations in the traditional forming processes employed to produce them. Oil pump stator has been studied as an instance to present the forming process of asymmetric wall products. First, a theoretical analysis of the forging's forming process has been made. Second, a rigid-visco-plastic finite element model of oil pump stator has been constructed and three dimensions FEM simulation and analyzing of extruding process have been taken by employing the simulation software. At last, parameters of the forming process have been optimized, the rule of forging's metal flow in the forming process has been analyzed and some distributions of stress and strain have been offered. These data can be use to direct the production of the other asymmetric wall forgings. 相似文献
49.
The improved Analytic Hierarchy Process is adopted for the optimal decision of waste water treatment process. The unified test of traditional method is avoided owing to using the three scale method and inducting the optimum transfer matrix and then converting into the unified judgement matrix. It is proven by example that it is feasible to use the improved Analytic Hierarchy Process in the optimal decision of the waste water treatment process. 相似文献
50.
Bomsster is a key load-bearing part of railway lorry bogie.Because of its inherent defects casting-steel bomsster could not meet the demands of the heavy load,acceleration and security for lorry.So forging process is proposed to form it.The forming performance of forging-steel bomsster is analyzed.A forging technology is presented which realizes two forging-steel bomsster parts formed in one die.With the plastic forming simulation software DEFORM-3D,the simulation and optimization of the forming process of forging bomsster has been taken based on 3D rigid visco-plastic FEM theory.Optimized scheme has been used to direct the pilot product.The results of product's testing and application suggest that the new forging technology is feasible and the performance of the product is credibility and stabilization.The factory has realized large scale production of a series of forging-steel bomsster.Remarkable benefits of both economy and society have been achieved. 相似文献