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采用辐照法将二甲基二烯丙基氯化铵接枝共聚于预处理的水稻秸秆,考察了产物对于阴离子染料和COD的吸附性能,结果表明接枝后秸秆有吸附阴离子的效果.研究了溶液pH值、吸附时间和温度对吸附过程的影响,吸附剂对于阴离子染料与COD的最大吸附量分别为335 mg/g和73 mg/g. 相似文献
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Development and optimization of fish‐fortified instant noodles using response surface methodology 下载免费PDF全文
Unnikrishnan Parvathy Jaganath Bindu Chalil George Joshy 《International Journal of Food Science & Technology》2017,52(3):608-616
Proper and sensible formulation of ingredients in noodles facilitates its calorie cut down thus making it healthier. Fish being a source of cheap and quality protein can serve in the fortification of noodles. Hence, a study was done to formulate and develop fish noodles from Nemipterus japonicus. D‐optimal mixture experimental design with 15 runs was formulated to optimise the different levels of ingredients for noodles. Influence of different ingredients, viz. fish mince, wheat and refined wheat flour (maida) and potato starch, on the physical, cooking and sensory properties of fish noodles was evaluated. The protein content of noodles increased with increase in the fish mince incorporation. Water absorption capacity (WAC) was found to be directly related to the potato starch concentration. Positive correlation was observed between noodle protein content and cooking time. Desirability function scores revealed a noodle combination of 45% fish mince, 47% wheat: maida (1:1) mix and 8% potato starch as optimum. 相似文献
155.
A farm-scale biogas plant loaded with untreated rice straw and co-digested with raw pig wastewater was operated and monitored during a complete digestion cycle. One active anaerobic digester cell (6600 m3) containing 727 tons of rice straw, 285 tons of pig wastewater and approximately 1300 tons of water was operated for a total of 422 days. Cumulative energy production of 295 MWh and an estimated specific methane yield of 181 LCH4/kgVS added was achieved. A direct correlation between daily power production and digester temperature was observed, with a maximum power production of 2.74 MWh/d. Mesophilic conditions were reached inside the digester during the summer months by recovering waste heat from the engine and recycling it through the leachate recirculation process.A slow start-up period of approximately 200 days was observed, but increased leachate recirculation rates (from 0.04 to >0.14 m3/m3straw-d) resulted in increased gas production that initiated the microbial growth phase in the digestion cycle. Although sufficient buffering capacity as well as macro- and micronutrients were supplied to the system by the pig wastewater, an overall straw (dry wt.) to wastewater ratio (wet wt.) of 1 to 1.4 is recommended to improve gas production and decrease the acclimation period. A raw economic assessment of the system shows an investment recovery time of 8.3 years. Improvements such as continuous leachate recirculation, a more efficient heat exchange system to maintain mesophilic conditions year round, and periodic addition of fresh wastewater and sludge acclimated to lignocellulosic material are recommended to achieve a more sustainable and profitable system. 相似文献
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本文映示了小麦润麦过程中水分在小麦颗粒中扩散的路径.通过将杜伦麦、软麦在含有萤光试剂的溶液中浸泡12,24,48h之后,萤光切片图像显示出色剂.首先是通过麦胚进入麦粒,再由珠心层传送到麦粒的另一端,同时由糊粉层进入到胚乳.色剂沿背部一侧传送要比腹沟一侧快.皮部吸水速度快,而种皮有抵制水份进入胚乳的作用.从微观观测看出,细胞壁(膜)的三维网状结构形成了水份传送的渠道.色剂在细胞壁里的运动是毛细作用,而在胚乳细胞内的运动则是渗透作用.色剂在细胞壁里的运动要快于在胚乳细胞内的运动.色剂在杜伦麦(硬麦)及软麦里的运动模式是相同的,但是色剂进入软麦的速度要比进入杜伦麦快. 相似文献
157.
利用碳酸乙烯酯(EC)为液化剂在常压条件下对油菜秸秆进行了液化试验。选择甲烷磺酸(MSA)作为最优催化剂,探讨了反应温度、反应时间、物料量、催化剂量4个因素对液化得率及黏度的影响。采用二次回归正交旋转组合设计对其液化工艺进行了优化。结果表明:最佳液化条件为反应温度165℃,反应时间70 min,物料量15.5%,催化剂量3.2%。在此条件下,液化得率可达到92.89%。 相似文献
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F.M. Valle-Algarra E.M. Mateo Á. Medina F. Mateo J.V. Gimeno-Adelantado 《Food additives & contaminants. Part A, Chemistry, analysis, control, exposure & risk assessment》2013,30(6):896-906
Ochratoxin A (OTA) and type B trichothecenes are mycotoxins that occur frequently in cereals and thus can be found in cereal by-products such as bread. The aim of this work was to study the variation of the levels of OTA, deoxynivalenol (DON), 3-acetyldeoxynivalenol (3-ADON) and nivalenol (NIV) during the bread-making process. This was done by using wheat flour spiked with different levels of toxins. Mycotoxin levels were controlled after fermentation of the dough with yeasts (Saccharomyces cerevisiae) and after further baking at different temperature–time combinations. Analysis of variance (ANOVA) of the results showed a significant reduction in OTA level (p < 0.05) during fermentation of the dough. The reduction ranged between 29.8% and 33.5%, depending on the initial concentration of toxin in the flour. During this period, the level of the other mycotoxins studied was not modified. By contrast, in the baking phase there were significant changes in the levels of the four mycotoxins, although the reduction was similar under all the baking conditions. Considering all the temperature–time conditions tested, it can be concluded that during the baking period the average reduction of OTA, NIV, 3-ADON, and DON was 32.9%, 76.9%, 65.6%, and 47.9%, respectively. 相似文献
160.