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31.
煤炭是我国的主要能源,是国民经济和社会发展不可缺少的物资基础。随着日本核事故的发生,核电发展"被"放缓,而全球煤炭需求将增长。本文主要介绍了煤炭资源在我国国民经济中的需求状况,分析了煤炭产业在我国发展中所面临的一些问题,并提出了煤炭产业发展的一些建议。 相似文献
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Jong H. Lee Sae K. Lee Kwan H. Park In K. Hwang Geun E. Ji 《International journal of food microbiology》1999,50(3):191
Twenty-two amylolytic bifidobacteria grown in BHI-starch media were compared for the amylase activity of the intra- and extra-cellular enzymes. The activity of the cells grown in the liquid medium differed considerably. Among the strains tested B. adolescentis Int57 and B. adolescentis ZS8 exhibited higher activities than others. In rice medium containing 0.05%
-cysteine·HCl and 0.2% yeast extract, the amylolytic Bifidobacterium strains grew considerably better than non-amylolytic Bifidobacterium strains. B. adolescentis Int57, which showed highest growth and amylase activity in the rice medium, was chosen and rice fermentation was investigated. The titratable acidity (TA) reached 2.43 and pH decreased to 4.4 after 24 h fermentation. The relative ratio of acetic acid to lactic acid gradually decreased during fermentation. The concentration of reducing sugar and amylase activity gradually increased and reached 14 mg maltose equivalent/ml and 35 mU/ml min, respectively, in 24 h. The accumulated reducing sugar was mostly maltotriose. The layer-separation of fermented product was stabilized by the addition of 1% gelatin. It was suggested that amylolytic bifidobacteria may be used for the production of fermented rice products. 相似文献
34.
Influence of fermentation time on the development of compounds responsible for quality in black tea 总被引:3,自引:0,他引:3
The compounds responsible for tea quality, such as theaflavins (TFs) and thearubigins were found to increase with fermentation time. However, TF reached a maximum, declining subsequently. The water extract of black tea decreased with fermentation time. Caffeine concentration remained unchanged. The digallate equivalent of theaflavin, colour index and briskness index were found to peak at the optimum fermentation time. Polyphenols declined more quickly during the initial stages, followed by a steadily declining trend. Fermentation time had little impact on the gallic acid concentration. Among the catechins, epigallocatechin oxidized fastest, followed by epigallocatechin gallate and epicatechin gallate. 相似文献
35.
Bo Yu Zhao-Xin Lu Xiao-Mei Bie Feng-Xia Lu Xian-Qing Huang 《European Food Research and Technology》2008,226(3):415-421
Many bioactive peptides possess specific biological properties that make these potential ingredients of health-promoting foods.
Increasing attention is being focused on physiologically active peptides derived from soybean proteins. In this study, soybean
peptides were produced by fermentation of defatted soybean meal with Bacillus subtilis SHZ and purified by ultrafiltration and gel chromatogram. Free radical scavenging property and the effect on anti-fatigue
of the peptides were evaluated in vitro and in vivo, respectively. Swimming endurance tests of mice were carried out after
20 days of soybean peptides administration (0, 100, 200, 400 mg/kg BW/day for control, low-dose, middle-dose and high-dose
group, respectively). And the blood lactate and hepatic glycogen of mice were determined. Results showed that the purified
peptides exhibited significant (P < 0.01) scavenging potencies on superoxide (62%) and hydroxyl (96%) at a concentration of 10 mg/ml. The average swimming
time of the low-, middle- and high-dose group was increased by 20.91, 45.45 and 70% compared with that of control group, respectively.
And administration with soybean peptides could significantly accelerate the clearance of blood lactate after mice swimming
(P < 0.01). The hepatic glycogen storage of middle and high dose groups were obviously increased (P < 0.05). It suggested that the soybean peptides produced by fermentation could significantly alleviate physical fatigue of
the mice. 相似文献
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介绍了微机DCS系统在柠檬酸发酵上的应用,阐述了系统软硬件的设计方法及有关可靠性措施。 相似文献
39.
Simultaneous delivery of antibiotics neomycin and ampicillin in drinking water inhibits fermentation of resistant starch in rats 下载免费PDF全文
40.
Monitoring of monosaccharides,oligosaccharides, ethanol and glycerol during wort fermentation by biosensors,HPLC and spectrophotometry 总被引:1,自引:0,他引:1
The aim of the present study was to analyze sugar levels (namely maltose, maltotriose, glucose and fructose) and alcohols (ethanol and glycerol) during the fermentation process in wort samples by amperometric enzymatic biosensors developed by our research group for industrial application, HPLC and spectrophotometry, and to compare the suitability of the presented methods for determination of individual analytes. We can conclude that for the specific monitoring of maltose or maltotriose only the HPLC method was suitable. On the other hand, biosensors and spectrophotometry reflected a decrease in total sugar concentration better and were able to detect both glucose and fructose in the later stages of fermentation, while HPLC was not. This can be attributed to the low detection limits and good sensitivity of the proposed methods. For the ethanol and glycerol analysis all methods proved to be suitable. However, concerning the cost expenses and time analysis, biosensors represented the best option. 相似文献