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21.
Helen N. Asemota Max A. Wellington Adewale A. Odutuga Mohammed H. Ahmad 《Journal of the science of food and agriculture》1992,60(3):309-312
The effect of short-term storage on the protein, phosphorus and phenolic content as well as peroxidase and o-diphenolase activities of cut, harvested Jamaican yam (Dioscorea sp) tubers (D rotundata. D alata and D cayenensis) was studied. There was an initial increase in the total phenolic content up to the third week of storage followed by a gradual decrease to the sixth week. Phenolic content was found to be highest in D cayenensis followed by D rotundata and D alata. The activities of peroxidase (EC 1. 11. 1. 7) and o-diphenolase (EC 1. 10.3.1) increased steadily up to the third week of storage and thereafter decreased to the fifth week. The intensity and rapidity of browning in tubers when cut, correlated very closely with the tuber o-diphenolase and phenolic content levels while the onset of rotting correlated with the peroxidase activity levels in the species studied. 相似文献
22.
对红麻料片进行压缩性能、模拟打包和全秆打包试验,并进行了堆贮观察与霉变试验分析,确定出了红麻原料的成包条件;根据试验并参考现有棉花和草料打包,提出三种红麻料片的适宜打包规格、水分和密度等。根据红麻料片压缩性能试验,提出红麻全秆、红麻秆和红麻皮压缩特性的数学方程,为制定红麻原料的打包工艺提供了依据 相似文献
23.
Review: Modified Atmosphere Packaging and its effects on the microbiological quality and safety of produce 总被引:10,自引:0,他引:10
Carol A. Phillips 《International Journal of Food Science & Technology》1996,31(6):463-479
Modified Atmosphere Packaging and related technologies are increasingly used to extend shelf-life of fresh produce. This paper reviews the effect of such technology on the spoilage microbiological flora and food-borne pathogens which may be present in produce and also on the organoleptic properties of the product. 相似文献
24.
应用现代可靠性理论,从设计、工艺、技术等方面对油田集输系统进行了可靠性探讨,提出了增强系统可靠性的措施。 相似文献
25.
Lithium-ion batteries are becoming more and more important not only for portable electronic devices, but also in prevision of high power electric vehicles. In such an optic, deep studies regarding all the components of a secondary battery are in development. In this study, high voltage cathode materials have been selected. Crystals with spinel structure have a 3D vacancy pathway suitable for Li-ions transport. The material under study was LiNi0.5Mn1.5O4 doped with magnesium replacing the nickel. Various samples were synthesized via three different routes: a solid-state method, a modified sol–gel method and a xerogel method. The structure and morphology of the powders were analyzed with HRTEM and XRD. Electrochemical tests were also performed. A wide range of particle sizes (from micro to nanosize) was the result of the different synthesis routes. Unfortunately pure materials were not always obtained. The electrochemical tests showed improvement of the material's cyclability, by reducing the particle size. The electrochemical tests further confirmed the existence of a Li1+dMn2−dO4 impurity. The results are quite promising, however, further improvement of the purity of the electrode composition are needed. 相似文献
26.
Magnesiumandmagnesiumalloyshavebeenin vestigatedashydrogenstoragematerialsforseveralde cadesbecausefarmorehydrogenbyweightcanbestoredinthemthaninmostoftheothercurrentlyknownhydrogenstoragealloys .Moreover ,thehighnaturalabundanceofMg ,itslightmassandenviron mentalcompatibilitypotentiallymakemagnesiumoneofthemostprospectivecandidatesforfuturehydrogenstoragematerials .Unfortunately ,thepracticalappli cationofMganditsalloyshasbeenlimitedonlytocertainstoragedevicebecauseoftheirpoorhydriding dehydr… 相似文献
27.
通过改进铅膏的配方及极板的独特处理工艺 ,提高了干电荷电摩托车电池的低温高率放电性能、充电接受能力和储存性能 ,完全可以满足国内外摩托车主机厂的各种要求。 相似文献
28.
本文着重介绍了在可研究性阶段,通过对深圳抽水蓄能电站上水库主坝设计过程中坝型选择的相关因素的分析,确定其大坝类型的过程。 相似文献
29.