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141.
142.
对污泥膨胀的影响因素、假说、控制方法进行了综述,重点分析了厌氧选择器、缺氧选择器和好氧选择器的特点,以解决污泥膨胀这一污水生物处理中遇到的问题。 相似文献
143.
144.
Whole maize plants at the milk and dough maturation stages were ensiled in August and October 1984, for periods of 45 and 40 days, respectively. Thirteen net bags containing herbage samples were buried at different locations within the silo to determine changes and losses during the conservation period. Thermocouple wires and small-diameter plastic pipes were connected to every bag for temperature and gas measurements. Air penetration in the upper layer was much faster than in the inner parts. Losses in dry matter of 3.9-7.4% were found in well sealed sites in the bunkers, and of up to 36% at locations where air penetrated. The rate of air penetration into the silage and temperature at various sites in the bunker were recorded. Correlation between CO2, and N2, contents in the silage was very high (r2 = 0.995) whereas oxygen levels were close to zero. 相似文献
145.
电导微生物技术快速测定原料乳菌落总数的研究 总被引:1,自引:0,他引:1
从乳品电导率微生物学的角度研究了快速测定原料乳菌落总数的原理。向计算机(MALTHUS计算软件)中一一对应输入平皿菌落计数值的log值与检测时间,当输入50组以上数据时曲线自动生成。将电导测定方法与常规方法测定结果相比较,结果较理想。电导率微生物检测提供了传统微生物测试所不能比拟的优点。结果表明,该方法具有快速测定、方便、资料自动搜查、允许样品随时插入测试的优点,原料奶得以更快速的监测,适合用于原料乳的微生物指标的质量控制。 相似文献
146.
Aeration of pitching yeast signicantly increases the metabolism of acetate. This increase is particularly noticed at an enzymatic level, with special reference to the specific activity of the Fe+++ linked pyruvate de-carboxylase which has been shown to be involved in the production of acetic acid. At the beginning of fermentations carried out with aerobic and anaerobic pitching yeasts, an increase in acetic acid production is observed, this is followed by reabsorption. Stabilisation in the concentration of acetic acid is observed until the end of fermentation. Initial and final concentrations of acetic acid obtained during fermentations were significantly higher in fermentations carried out with aerobic pitching yeasts than in fermentations carried out with anaerobic pitching yeasts. 相似文献
147.
Osei Safo-Kantanka Joseph Owusu-Nipah 《Journal of the science of food and agriculture》1992,60(1):99-104
Thirteen cassava (Manihot esculenta L Crantz) varieties from three successive annual harvests were screened for the mealiness of the cooked tuber, and the elasticity and smoothness of the pounded paste. Six were selected for further studies based on their mealiness and the starch and dry matter contents were determined. The diameter of the starch granules of the selected varieties and those of an irradiated M1 V2 population were measured. Microscopic examinations of the raw and cooked cells of the irradiated M1 V2 population were made. Correlations among all the parameters were studied. Varietal and seasonal differences in cooking quality were observed. There was no consistent relationship between mealiness of the boiled tuber and the elasticity and smoothness of the pounded paste. Varieties that were mealy were high in dry matter and starch content. The starch granules of mealy varieties were larger than those of nonmealy ones. There were no differences between mealy and non-mealy varieties in the arrangement of the cells or ‘cell condition’, of the raw tubers. However, the cells of the cooked tubers were held less cohesively, ie there was more ‘cell disorganisation’, in mealy varieties than in non-mealy ones. 相似文献
148.
研究有氧运动联合补充D-核糖对小鼠抗疲劳和抗氧化酶活性的影响,将小鼠分为安静对照组、有氧运动对照组、D-核糖对照组、D-核糖+有氧运动组。有氧运动组进行每周进行6 d的有氧跑台训练,D-核糖组每日每只灌胃2 mL核糖(300 mg/100 g),通过12周的规律性有氧跑台训练后,建立小鼠负重游泳抗疲劳动物模型,分别记录小鼠负重力竭游泳时间,并测定小鼠体内肝糖原(hepaticr glycogen,HG)、肌糖原(muscle glycogen,MG)、血糖(blood glucose)、血尿素氮(blood urea nitrogen,BUN)、血乳酸( bloodlactic acid,BLA)、丙二醛(malondialdehyde,MDA)含量和总抗氧化能力(total antioxidant capacity,T-AOC)、谷胱甘肽过氧化物歧化酶(glutathione peroxide dismutase,GSH-Px)、超氧化物歧化酶(superoxide dismutase,SOD)、过氧化氢酶(catalase,CAT)等活力。结果表明,与安静对照组相比,有氧运动对照组、D-核糖对照组、D-核糖+有氧运动组小鼠负重游泳时间显著增加(P<0.05),同时显著提高了小鼠体内肝糖原、肌糖原和血糖含量(P<0.05),并降低了体内血尿素氮和血乳酸含量(P<0.05)。另外,其抗氧化活性结果表明,与安静对照组相比,有氧运动对照组、D-核糖对照组、D-核糖+有氧运动组的T-AOC均增强,SOD、CAT、GSH-Px活性也都显著升高(P<0.05),MDA则显著降低(P<0.05)。说明长期规律的有氧运动联合补充D-核糖能显著提高机体内肝糖原、肌糖原、血糖含量和氧化应激能力,提高机体抗疲劳作用。 相似文献
149.
On the gelation of mungbean starch and its composites 总被引:1,自引:0,他引:1
Parichat Hongsprabhas 《International Journal of Food Science & Technology》2007,42(6):658-668
Light microscopy and the concentration dependence of the elastic modulus of mungbean starch (MB) gel indicate that the gelation of MB is mainly governed by a close‐packing mechanism. The mechanical property of the entire network is influenced by the strength of swollen amylose‐rich discrete gel particles rather than the surrounding matrix. However, when the physicochemical properties of the surrounding matrix is altered by the presence of flour fillers possessing lower gelatinisation temperature and enthalpy, both the stress‐related and strain‐related parameters of MB‐based mixed flour gels were reduced (P < 0.05). Addition of iota‐carrageenan (1.0% w/v), in both the absence and presence of calcium lactate (0–20 mm ), further reduced both the stress‐related and strain‐related parameters of the composite gels. This study shows the detrimental effect of the anionic hydrocolloids and divalent cation addition on the mechanical properties of a composite structure stabilised by close‐packing mechanism. 相似文献
150.
饲料料仓是一种常用的饲料存储设备,一般采用钢板焊接及螺钉联接而成。它具有结构简单、制造方便、应用场合多的特点。料仓功用包括对散装物料的接收、贮存、卸出和料位指示等。饲料属于散体,会对所承载的料仓侧壁产生一定压力从而致其变形。为了避免应力过大导致事故,需要可靠的理论分析和正确的计算,并对其进行结构优化设计。 相似文献