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以丙烯酰胺(AM)和丙烯酰氧乙基三甲基氯化铵(DAC)为共聚单体.采用分散聚合法在无机盐水溶液中得到了性能稳定的聚合物乳液。对所得产物进行红外光谱和粒径分析,并将所得阳离子聚丙烯酰胺(CPAM)用于漂白麦草浆试验,结果表明,自制的CPAM能显著提高浆料中填料的留着率并改善浆料的滤水性能。 相似文献
184.
微生物发酵稻草生产饲料工艺研究 总被引:3,自引:0,他引:3
利用稻草粉作为发酵基质,通过对培养基配方、培养基含水量、发酵温度及发酵周期的研究,探索到微生物发酵稻草生产饲料工艺条件为:稻草粉80 g、玉米粉19 g、尿素1 g、葡萄糖2 g、磷酸二氢钾0.1 g,培养基含水量为1∶2,发酵温度为30℃,发酵周期为6 d。产物分析结果表明:采用优化工艺进行发酵,发酵后稻草粉的纤维素含量为22.34%;粗蛋白含量达22.08%,可溶性糖含量为3.87%。 相似文献
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Ahoefa Agbagla‐Dohnani Agns Cornu Pierre Nozire Jean‐Michel Besle Jean‐Pierre Dulphy Michel Doreau Elisabeth Grenet 《Journal of the science of food and agriculture》2003,83(5):383-394
The chemical composition, intake, digestibility, ultrastructure and microbial degradation of rice straw from Camargue were compared with barley straw. These variables were observed in two different herbivore digestive ecosystems: the sheep rumen and the donkey caecum. The two straws differed essentially in their ash content, which was three times higher in rice, owing to its silica content. Other chemical components were comparable, except a higher phenolic acids‐to‐lignin ratio in rice. Rice straw was better ingested than barley straw. Organic matter and neutral detergent fibre digestibilities were the same in both straws. Dry matter and cell wall disappearances could be adjusted to the exponential modelling equation with lag time, and differed between animals but not between straws. The sheep rumen had a higher extent of degradation, but the donkey caecum had a higher degradation rate. Statistical analysis revealed that cell‐wall components degradation was similar in the two straws except for ferulic acid, which was more degraded in rice straw. Scanning electron microscopy showed important differences in parenchyma degradation, which was much more effective in rice. Copyright © 2003 Society of Chemical Industry 相似文献
187.
以秸秆和煤为原料制备复合颗粒燃料,利用全生命周期评价方法,研究颗粒燃烧取暖全生命周期过程中的能源消耗和环境影响。结果表明:颗粒燃料取暖全生命周期过程中能量投入为908 MJ/t,燃烧释放热量15490 MJ/t,能量产出投入比为17.1,能源转化效率较高。颗粒燃料的能量投入主要来自玉米种植,种植过程中的氮肥使用消耗较多能量。对气候变化(GWP)和酸化(AP)贡献较大的清单数据为颗粒燃料的燃烧,其中燃烧污染物排放的直接贡献最大,贡献率分别为53.22%和46.08%;对水资源消耗(WU)贡献较大的清单数据为颗粒燃料的压制,贡献率为71.56%;对富营养化潜值(EP)贡献较大的清单数据为颗粒燃料燃烧后的废渣排放,贡献率为43.40%。 相似文献
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Secundino Lpez David R Davies F Javier Girldez MS Dhanoa Jan Dijkstra James France 《Journal of the science of food and agriculture》2005,85(9):1550-1557
The nutritive value of 17 straws was determined on the basis of their chemical composition, in vitro dry matter (DM) digestibility and rumen fermentation kinetics (from gas production curves measured in vitro). Five roughages were from the cereal species Avena sativa (oat), Hordeum vulgare (barley), Secale cereale (rye), Triticum aestivum (wheat) and Zea mays (maize stover). The other 12 samples were legume straws, two samples from each of the species Cicer arietinum (chickpea), Lens culinaris (lentil) and Phaseolus vulgaris (bean) and one sample from each of the species Lathyrus sativus (chickling vetch), Lupinus albus (white lupin), Pisum sativum (field pea), Vicia articulata (one‐flowered vetch), Vicia ervilia (bitter vetch) and Vicia sativa (common vetch). All samples were collected after harvesting from different farms located in León (northwestern Spain). Based on their chemical composition, digestibility and gas production characteristics, species could be clustered into two groups with a significant linkage distance, one for cereal straws that merged at a level of similarity of 80% and the other for legume straws with a degree of similarity of 50%. Species varied widely and significant differences (P < 0.05) were observed between the two groups of straws. Legume straws showed higher crude protein (74 ± 6.1 vs 29 ± 2.2 g kg?1 DM) and lower fibre (584 ± 18.1 vs 793 ± 27.5 g neutral detergent fibre kg?1 DM) contents than cereal straws and, consequently, DM digestibility coefficients (0.670 vs 0.609; standard error of difference 0.0054) and metabolisable energy values (7.4 ± 0.15 vs 5.7 ± 0.24 MJ kg?1 DM) were significantly greater in legume than in cereal straws. Although there were noticeable differences among species within each botanical family, legume straws showed better nutritional quality than cereal straws, indicating that they could be considered promising and interesting sources of roughage for incorporation into ruminant diets. Copyright © 2005 Society of Chemical Industry 相似文献
190.
Meenoti M. Patel Ranjan M. Bhatt 《Journal of chemical technology and biotechnology (Oxford, Oxfordshire : 1986)》1992,53(3):253-263
Alkaline peroxide pretreatment for the delignification of rice straw was optimised by varying the concentrations of H2O2 and NaOH and changing the temperature and duration of the pretreatment. Changes in the lignin content, content of total carbohydrates and weight loss were measured during the pretreatments. Maximum delignification of 62% was obtained by pretreating rice straw at 50°C for 5h with 1.5% (w/v) NaOH and 1% (v/v) H2O2, The preferential loss of hemicellulose and lignin from the straw resulted in an increase in the cellulose content of the insoluble residue after pretreatment from 47% (untreated) to 67.79% (treated). The product of this treatment is characterised by having higher cellulose digestibility than untreated rice straw. It also has use as a carbohydrate source in ruminant feed since the in-vivo digestibility by the cow increased from 56.85 % to 76.54% (P < 0.001). The treated rice straw could also be used for commercial process such as the generation of Single Cell Protein. Growth of Sporotrichum pulverulentum on treated rice straw gave a protein product of 24.41 % as compared to 3.8% on untreated rice straw. 相似文献