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81.
文章介绍了选择过一硫酸合成的最佳条件及进行生产的可行性。介绍了过一硫酸用于含铀煌斑岩、辉绿岩、花岗岩及炭板岩矿石提取铀时,与常规酸浸方法对比,有很好的经济效益和对环境的保护价值。 相似文献
82.
探讨肥料中有机质的分析方法。通过对两个肥料标准中有机质的分析方法进行比较,对各标准中有机质检验过程中的影响因素进行了分析,确定了本地区有机肥料中有机质适宜的分析方法。 相似文献
83.
《Drying Technology》2007,25(7):1193-1201
This work describes how probiotic bacteria can be dried at low temperature in two steps, combining spray drying and vacuum drying, in order to enhance their survival during storage. A sufficient number of dried probiotics survived storage for more than 3 months at 30°C, if an appropriate combination of protein and carbohydrate was selected as carrier and storage conditions were maintained optimal. The use of soy protein and maltodextrin or skim milk and arabic gum resulted in the best survival rates of probiotics during storage. No evident difference was found between different spray dryer configurations, although a cocurrent flow was preferred. 相似文献
84.
Enzymatic Browning in Apple Pulps 总被引:3,自引:0,他引:3
Enzymatic browning in Golden Delicious apple pulp was studied as related to degree of ripeness and temperature (3.5–31°C). Green apple pulp showed the highest rate of browning. This was attributable to differences in ascorbic acid (AA) content and polyphenoloxidase activity in young fruits. The rate of browning determined by CIE L* measurements followed complex temperature dependent kinetics, represented by a multiple linear effects with log time. Equal changes in L* parameter yielded straight lines in a log temperature vs log time plot. Inhibition with AA caused an initial slow rate of browning and a well defined break point associated with exhaustion of antioxidant properties of the AA. The greater the AA concentration the longer the initial period. 相似文献
85.
Afam I Jideani Richard K Owusu Apenten H G Muller 《Journal of the science of food and agriculture》1994,65(4):465-476
The effect of cooking on proteins from acha and durum wheat was assessed from an analysis of protein extractability, gel electrophoretic profiles, in-vitro protein digestibility (IVPD) and the amino acid compositions of wholemeal flour and residue proteins. Heating wholemeal flour samples at 100–140°C (t = 10–40 min) resulted in 0–30% and 45–55% decreases in acha and durum protein solubility, respectively. In general, high molecular weight (30–70 k Da) protein subunits were more susceptible to heat damage. For both cereals, sodium dodecyl sulphate (SDS; 10 g litre?1) and/or dithiothrcitol (DTT; 10 mM ) increased protein solubility in unheated and heated samples. The IVPD index was 90–91% and was not significantly altered by cooking (100–120°C, t = 40 min). Cooking at extreme temperatures (140°C, t = 40 min) reduced the IVPD by 8% (P = 0.05). Osborne fractionation resulted in a durum or acha residue level of 7.8% or 55.2%. Treatment with solvent containing propanol, SDS and/or DTT at room temperature followed by SDS-polyacrylamide gel electrophoresis of non-solubilised proteins showed that the glutelin fraction of acha, with the exception of a 65 kDa subunit, was insoluble owing to strong inter-subunit hydrophobic and disulphide interactions. Wholemeal acha flour and residue protein showed a significantly greater level of hydrophobic and sulphur amino acids as well as glutamine which is associated with H-bonding. The possibility that cereal protein solubility is also dependent on protein-carbohydrate links is discussed. 相似文献
86.
皮革去污上光用乳化蜡的研制 总被引:8,自引:0,他引:8
采用石蜡、微晶蜡为主要原料 ,经实验选出了以水为稀释剂的乳化型皮革去污上光蜡。实验优化的配方为石蜡 12 .5 g ,微晶蜡 8.0 g ,硬脂酸 8.5g ,三乙醇胺 5 .5 g ,水量 70 (涂用 )或 130 g(喷用 )。反应条件为乳化时间 4 0min ,搅拌速度 5 0 0~ 70 0r/min ,乳化温度 90℃。制得上光剂产品的去污性能可与用去污剂单独处理的效果相当 ,亮度可达 6 6 .7。 相似文献
87.
The erucic acid content of broccoli florets, sprouts, and seeds was found to be about 0.8, 320, and 12100 mg/100 g, respectively. Using the erucic acid limit established for canola oil in the U.S.A. and Canada as a guideline, the estimated dietary intake of erucic acid from florets and sprouts was considered of little consequence, whereas in seeds a relatively small amount (about 35 g/wk) equaled our calculated exposure limit for erucic acid. Additionally, the most complete fatty acid distribution yet published for the various forms of broccoli are presented. 相似文献
88.
佳木斯造纸厂从芬兰奥斯龙公司引进了一套新型、高效、低碱流失的压力过滤、洗涤苛化系统。本文就如何延长该系统主体元件──滤套的使用寿命这一技术问题,进行系统的阐述。 相似文献
89.
90.