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1.
蛋白质水解度测定方法综述   总被引:27,自引:0,他引:27  
对目前国内外常用的蛋白质水解度测定方法进行了综述,其中pH—state方法是通过滴定水解过程中释放的质子测定DH;OPA、TNBS及国内常用的水合茚三酮和甲醛等测定方法是利用游离氨基的反应测定DH。  相似文献   

2.
研究了聚多元羧酸盐的合成方法及反应机理,将其应用于洗涤剂和PVC制品中分别代替三聚磷酸钠和邻苯二甲酸二丁酯,证明有良好效果。  相似文献   

3.
SUMMARY: A partially purified immunoglobulin G (lgG) solution prepared from the serum of species to be tested was heated to the specifications for sausages. The resulting supernatant fluid was decanted and the precipitate washed with saline and used to immunize rabbits. The supernatant fluid was used to sensitize tanned sheep red blood cells. The immune serum was rendered monospecific by absorptions with heterologous, heated lgG precipitates. A sample of monospecific immune serum was absorbed with a washed homogenate of sausage. Aliquots of the monospecific immune serum, both untreated and sausage absorbed, were tested with cells sensitized with the homologous heated lgG supematant fluid. A significant reduction of titer by sausage absorption indicated that the sausages contained the meat homologous to the immune serum.  相似文献   

4.
SUMMARY— The mechanism and generality of the known stabilization against autoxidation conferred on linoleic acid by certain basic amino acids, such as lysine and arginine, was investigated. Basic amino acids were the only class of compounds found to confer the effect. However, the smallest basic amino acid, 2,3-diaminopropionic acid, was not effective, nor was αβω-diaminc acid, 3,6-diaminohexanoic acid, although a simple isomer of lysine. The stabilization was observed only in the solid phase. Inclusion of sodium chloride in the solid matrix was deleterious to the effect. A large number of physical and chemical observations were made and correlated but it has not been possible to draw detailed conclusions about the mechanism of stabilization, nor can a detailed structure of the stabilized complex be suggested. The cause of the phenomenon appears to be closely associated with the physical arrangement of the ions in the crystal lattice.  相似文献   

5.
Hop oil emulsions prepared from different varieties of hops have been found to exhibit enhanced physical stability on the addition of blends of the emulsifiers Span 20/Tween 80 or Span 60/Tween 60. Examination of the particle size and volume distributions of an emulsion by use of a Coulter Counter was found to be an excellent method of monitoring its stability. An indication as to the relative efficiency of emulsifiers can be obtained from Coulter Counter measurements on hop oil emulsions after storage for 4 days. The use of an ultracentrifuge provies a rapid means of testing emulsion stability and hence the effectiveness of emulsion stabilizers.  相似文献   

6.
The lengths of chains of cells of Saccharomyces cerevisiae were studied during fermentation. Pitching yeast generally contained about half of the total number of cells as two-celled chains. The chain lengths varied during the subsequent fermentation and the variations were characteristic of the strain. Electronic counting assessments of chain length were unreliable.  相似文献   

7.
本文论述了计算机辅助选择造型方法,以探讨计算机辅助教学的选题、编程、使用等技术.  相似文献   

8.
本文基于点的复合运动理论,用球坐标法推导出点的速度及加速度的计算公式,进一步论证了理论力学中点的速度,加速度公式的正确性。  相似文献   

9.
影响大豆分离蛋白乳化稳定性测定的几种因素研究   总被引:2,自引:0,他引:2  
采用离心法对影响大豆分离蛋白乳化稳定性的测定结果的几种因素进行了研究。通过研究得出如下结论:对乳化稳定性影响最大的是油相体积分数,然后依次是蛋白质溶液浓度、pH、离子强度、离心速度。在测定的范围内,均质速度、均质时间、水浴加热时间、加热温度和离心时间对测定结果的影响都很小。  相似文献   

10.
The phototransformation of the α-acids (humulone) of hop resins has been studied in order to improve their bitter properties and to establish the optimal experimental conditions.  相似文献   

11.
ABSTRACT— The effect of time, temperature and rpm of comminution of emulsions was determined on the dispersion of approximately 25% of beef fat, pork fat or cottonseed oil in frankfurters. The numbers of lipid particles 5 μ or less in diameter increased in frankfurters containing either beef or pork fat as comminution was continued to higher temperatures, with pork fat dispersed more thoroughly. Fat tended to separate from frankfurters containing beef fat in particles 200 μ or more in diameter. In contrast, no specific degree of dispersion of particles 5 μ or less in diameter consistently indicated emulsion stability, or its lack. Increased rpm during comminution produced an increased dispersion of beef or pork fat. Under the same conditions pork fat was dispersed more finely than beef fat. Dispersion of cottonseed oil produced finely dispersed particles beyond the resolution of light microscopy, as was confirmed by electron microscopy which showed a substantial number of particles to be less than 1 μ in diameter.  相似文献   

12.
The quantitative analysis of the reaction products of the water activity dependent nonenzymatic glycosylation of lysozyme was not straightforward. Difficulties arose in the determination of the number of bound glucose molecules because glycosylation leads to glucose mediated protein aggregation, and the likely presence of a mixture of relatively labile Schiff-base intermediates, and the more stable ketoamine products generated by Amadori rearrangement. Polyacrylamide gel electrophoresis was used to monitor protein aggregation; periodate oxidation, nuclear magnetic resonance (NMR), and oxalic acid hydrolysis combined with HPLC, emerged as the most promising methods to quantitate the degree of glycosylation. Possible interpretations are advanced to explain the apparent discrepancies in degree of glycosylation suggested by the different analytical methods evaluated.  相似文献   

13.
本文论述了过低的棉短绒成熟度会引致粘胶生产过程压榨困难和过滤障碍。描述了在蒸球内设置中通管、来用重蒸轻漂、稳定漂白聚合度、以及漂后的除杂疏解等先进的工艺制造棉浆粕,有助于反应性能的提高,改善粘胶的过滤性能。但打浆时过分切断使纤维长度过短,会影响碱纤维素的压榨。采用干毯抄浆、浆粕存放(一段时间)均有助于浆粕水份均匀性的提高。  相似文献   

14.
枣果资源的加工利用研究进展   总被引:4,自引:0,他引:4  
概述了枣的营养价值及加工现状,并就如何更好地利用枣果资源提出了一些建议。  相似文献   

15.
灵芝不同部位多糖含量测定   总被引:8,自引:0,他引:8  
采用苯酚-硫酸法对灵芝菌盖表皮层、木栓层、菌柄、孢子粉、发酵菌丝体等部位中的灵芝多糖进行了测定,结果发现,灵芝发酵菌丝体中的多糖含量明显高于灵芝的其它部位,其含量顺序分别为:发酵菌丝体〉菌盖表皮层〉孢子粉〉菌柄〉木栓层。  相似文献   

16.
胶原蛋白的提取工艺研究   总被引:4,自引:0,他引:4  
探讨了胃蛋白酶法从猪肌腱中提取胶原蛋白的工艺.从酶浓度和酸浓度两个重要影响因素对工艺进行优化.并利用傅立叶变换红外光谱对胶原结构进行鉴定,同时采用高效液相色谱对所提胶原蛋白进行氨基酸组成分析.  相似文献   

17.
A method for the determination of the filterability of beer has been evaluated by members of the European Brewery Convention Analysis Committee. The method is based on the filtration of a beer sample, with a standard amount of diatomaceous earth (DE), under standardised conditions. Repeatability of the test was quite good, however the predictive value of the test is still questionable since no direct correlation could be established between the different filtercake values and industrial filtration problems. No collaborative test was performed as the filterability has to be determined on unfiltered beer; the test is easy to run, and as for the other filterability tests, day to day practice in a brewery will reveal its usefulness.  相似文献   

18.
百年风尚     
《中国服装(北京)》2013,(19):130-133
一场流光溢彩、赏心悦目的展览,一段百年风尚演进的传奇旅程,一次东西方文化艺术的完美对话。2013年9月13日,“博萃臻艺一中西方珍宝艺术展”在辽宁省博物馆举行了隆重的开幕仪式,法兰西共和国驻华大使白林女士、辽宁省文物局局长丁辉先生、辽宁省博物馆馆长马宝杰先生、卡地亚全球总裁兼首席执行官邓阁仕先生、卡地亚区域行政总裁(北亚洲)陆慧全先生、卡地亚中国区首席执行官陆意斯先生、辽宁省文物店总经理张春鹰先生,以及众多文化界与文博界的贵宾齐聚一堂,共同见证了这场文化艺术盛事。  相似文献   

19.
针对我厂涤纶高速纺丝生产中多次发生设备预紧联接螺栓断裂现象,以螺杆挤压机计量头紧固螺栓预紧力炬计算为例,推导出预紧联接的一般计算方法,同时对使用国产螺栓替代进口预紧联接螺栓进行了简述。  相似文献   

20.
高产EPA和DHA藻株的筛选   总被引:3,自引:0,他引:3  
为筛选出高产EPA和DHA藻株,针对8种海洋微藻进行培养,测定了它们的最佳吸收波长和生长曲线一藻体在对数期末期收获.经过提取脂肪,进行皂化酯化处理后用气相色谱测定EPA和DHA的含量。结果筛选出EPA高产藻株为新月菱形藻,EPA产量为16mg/L占粗脂肪重的26%,占细胞干重的3.3%;等边金藻为DHA高产藻株,DHA产量为3.2mg/L,占粗脂肪重的9.1%,占细胞干重的5.2%。  相似文献   

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