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31.
本研究选用红薯为原料,采用生料发酵工艺生产燃料乙醇,研制出了一种适合红薯生料发酵用的复合酶,其最优组合为糖化酶 200U/g、淀粉酶20 U/g、蛋白酶5U/g、果胶酶5U/g.同时对影响红薯生料发酵的主要因素进行了研究,确定了生料发酵生产燃料乙醇的最佳工艺条件,即料水比为2.5∶1、初始pH为4.2、发酵温度为32oC、发酵时间为7天.  相似文献   
32.
Batch process monitoring based on multilevel ICA-PCA   总被引:1,自引:0,他引:1  
In this paper, we describe a new batch process monitoring method based on multilevel independent component analysis and principal component analysis (MLICA-PCA). Unlike the conventional multi-way principal component analysis (MPCA) method, MLICA-PCA provides a separated interpretation for multilevel batch process data. Batch process data are partitioned into two levels: the within-batch level and the between-batch level. In each level, the Gaussian and non-Gaussian components of process information can be separately extracted.I^2 T^2 and SPE statistics are individually built and monitored. The new method facilitates fault diagnosis. Since the two variation levels are decomposed, the variables responsible for faults in each level can be identified and interpreted more easily. A case study of the Dupont benchmark process showed that the proposed method was more efficient and interpretable in fault detection and diagnosis, compared to the alternative batch process monitoring method.  相似文献   
33.
香蕉醋的研制   总被引:2,自引:0,他引:2  
以香蕉汁为原料 ,经过产果胶酶活性强的二株霉菌的酶液的处理 ,在二株酵母菌、三株醋酸菌的共同作用下发酵 ,研究获得最佳发酵条件下的果醋 .即在香蕉∶水为 1∶1 5 ,糖度为 14 %、酒度调整为 9°的条件下 ,选择原料破碎程度高 ,酵母菌接种量在 5 % ,醋酸菌接种量在 10 % ,发酵温度在 2 5℃的发酵条件 ,可得到酸度在6 47% ,口感纯正、香味浓郁、风味协调的浅黄色新型果醋  相似文献   
34.
A newly isolated strain EL31410, producing elastase (E. C3. 4. 4. 7) with high elastolytic activity was identified asBacillus sp. In the medium optimization, it was found that wheat bran and soybean flour hydrosate were the best crude carbon and nitrogen source for enzyme production, respectively. Addition of corn steep flour can affect the bacterium growth and elastase production. A fractional factorial design was applied to study the main factors that affect the enzyme production, and central composite experimental design and response surface methodology were adopted to derive a statistical model for the effect of wheat bran and soybean flour hydrosate on elastase production. The experimental results showed that wheat bran had positive effect but soybean flour hydrosate had negative effect, on enzyme production. An initial concentration of 3.4% (w/v) wheat bran and 9.4% (v/v) soybean flour hydrosate were found to be optimal for enzyme production in batch culture. The time course of elastase production in the optimized medium composition was also described. Project (No. 300024) supported by the Zhejiang Provincial Natural Science Foundation of China  相似文献   
35.
以紫外线为诱变剂,用庆大霉素产生菌JY1-12为出发菌株,选育出性能优良的菌株JY3-5.经正交试验确定其最佳发酵培养基,研究了最佳发酵温度和初始pH值,使其摇瓶效价提高35.1%;30m3灌放大试验,比出发菌株效价提高19.2%.  相似文献   
36.
金针菇液体发酵条件的研究   总被引:2,自引:0,他引:2  
本文探讨了金针菇液体发酵时,不同的矿质元素、培养温度、摇床转速、培养天数对菌丝体产量的影响.结果表明:金针菇液体发酵的最佳培养条件为:最适矿质元素CaCO3,最适温度26℃,最适摇床转速110 rpm,培养时间5d.  相似文献   
37.
XML语言是目前网络上标准的数据描述语言和交换语言,在网络上的应用也越来越广泛,阐述基于XML的高职学分制选课系统的设计和实现方法。  相似文献   
38.
INTRODUCTION Elastase is an enzyme that attacks and solubi-lizes elastin. As elastase can degrade elastin (Mori-hara, 1967) that other proteases cannot; it has broad applications in medical therapy, food processing and daily use chemicals industry. Considerable eff- orts were made to screen the elastase-producing strains, to study its pathogen effect and its charac-terizations (Tsuzuki and Oka, 1965; Tsai et al., 1988; Sharon et al., 1997; Ozaki and Shiio, 1975). Shiio, 1975). Reporte…  相似文献   
39.
INTRODUCTION Livestock is one of the largest sources of meth-ane emission with 80~115 million tons produced peryear, equivalent to 15%~20% of total anthropogenicmethane (IPCC, 2001). The global cattle population isresponsible for 73% of methane emissions of alllivestock, and methane produced during ruminalfermentation represents a loss of 2%~15% of grossenergy intake and may contribute to global warming(Johnson and Johnson, 1995). Many researches hadbeen carried out to find ways to low…  相似文献   
40.
主要介绍DOS环境变量的成员及作用;DOS环境变量的设置、修改、取消;DOS环境变量与批处理文件的关系  相似文献   
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