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排序方式: 共有115条查询结果,搜索用时 15 毫秒
101.
Youna Hemery Ulla Holopainen Anna-Maija Lampi Pekka Lehtinen Tanja Nurmi Vieno Piironen Minnamari Edelmann Xavier Rouau 《Journal of Cereal Science》2011
Wheat bran is a composite material made of several layers, such as pericarp, testa and aleurone. It could be fractionated into purified fractions, which might either be used as food ingredients, or serve as a starting material for extraction of bioactive compounds. The aim of this work was to evaluate the potential of using electrostatic separation as a way to obtain purified fractions from wheat bran. Ultrafine-ground bran obtained either by cryogenic grinding or by grinding at ambient temperature was used as starting material. The ultrafine bran was then charged by tribo-electrification and introduced in a chamber containing two high voltage electrodes, where bran particles were separated depending on their acquired charge, allowing positively and negatively charged fractions to be collected separately. The particle size distribution, microstructure and biochemical composition of the obtained fractions were studied. The charge of the particles was influenced by their biochemical composition: particles rich in highly branched and cross-linked arabinoxylans (pericarp) were separated from particles rich in β-glucan, ferulic acid and para-coumaric acid (aleurone cell walls). The testa and the intracellular compounds from aleurone were not highly charged, neither positively nor negatively. The most positively charged fraction represented 34% of the initial bran, and contained 62% of the ferulic acid present in the initial bran. The yield of the separation process was good (5.4% loss), and could be further increased. 相似文献
102.
Michael S. Watt Ryan D’Ath Alan C. Leckie Peter W. Clinton Graham Coker Murray R. Davis Robyn Simcock Roger L. Parfitt John Dando Euan G. Mason 《Forest Ecology and Management》2008
The objectives of this study were to determine the influence of site, fertilisation and age on fibre length and develop predictive models of fibre length from a comprehensive set of climatic, edaphic and stand variables. Data were collected from a nationwide set of 22 site quality plots where Pinus radiata D. Don was established at high stand densities (40 000 stems ha−1) and grown over a period of 4 years. The main environmental drivers of fibre length were identified by assessing the strength of bivariate correlations and use of multiple regression. Path analysis was used as an extension to multiple regression to separate cause from effect and quantify the direct influence of variables significantly related to fibre length. 相似文献
103.
Depending on sowing month, temperatures during boll growth in the tropical dry season are potentially sub- or supra optimal for the fibre quality parameters length and strength. The aims of this research were to: (1) measure the effect of sowing date on the quality of fibre from cotton grown during the dry season as this was not known; (2) use the range in temperature created by varying sowing date in the dry season, to derive relationships with gin turnout, the fibre quality parameters length, strength and micronaire. Over three seasons, two Gossypium hirsutum (upland) cultivars and one Gossypium barbadense cultivar were sown from March to June at the Ord River (15.5°S), Western Australia. For the highest yielding sowing months of March and April, fibre length and strength were at or below market preference due to relatively low temperatures and solar radiation during early fibre development. Fibre micronaire achieved market preference at all sowing months due to favourable late season temperatures and radiation. It is likely that current G. barbadense cultivars will have short fibre when grown in the dry season. For fibre length and gin turnout quadratic responses (p < 0.05) to weighted minimum temperature were fitted for each cultivar, where the optimum minimum temperature was 18–20 and 16–17 °C, respectively. The cultivar differences in fibre properties observed here suggest that wider screening may identify G. hirsutum cultivars with suitable fibre length and strength in the dry season. It was demonstrated by weighting of temperatures for the contribution of the cohort of bolls pollinated each day; the variation in crop fibre quality and gin turnout in the field due to temperature can be predicted. 相似文献
104.
在新疆精准植棉模式下为筛选出棉纤维低糖的陆地棉种质资源及揭示不同铃室棉纤维可溶性糖含量的规律,采用硫酸蒽酮比色法对89份陆地棉品种资源3~5室棉朵(吐絮后的棉铃)的纤维可溶性糖含量进行测定,从中筛选出7份无糖材料(1.01~2 mg/g),占全部材料的7.87%。不同来源品种的纤维可溶性糖表现不同,可溶性糖含量由高到低依次为江苏、安徽、河北、新疆、四川、湖北、山西、山东、河南。全部参试材料除河北和山西材料4室铃的纤维可溶性糖含量高于5室铃,其他均是5室铃高于4室铃。中国陆地棉纤维可溶性糖含量高于国外。在不同品种系列间可溶性糖含量比较中,新疆陆地棉系列高于中棉所系列;杂交棉系列高于常规棉系列;中、晚熟棉系列高于早熟棉系列。对仅有的13份材料的3室铃进行比较,‘芽黄9103’和‘中-190’可溶性糖含量较低,均与其他材料有显著差异。对7份具有特殊植物学性状材料的不同铃室进行比较,发现5室铃的铃重较大,单铃种子数较多,子指较大,衣分率和单子皮棉产量较低,但对棉花纤维品质的影响不显著。 相似文献
105.
以辽宁绒山羊为父本,岢岚本地山羊为母本进行级进杂交,其F_1、F_2和F_3的产绒量随级进代数的提高而增加,周岁母羊分别比本地山羊提高103.68、121.30和139.13%
相似文献
106.
HN毒标为从我省某鸡场患有呼吸道症状和腺胃病变的病鸡只以一的株病毒,在鸡胚中能稳定传代并且有规律性死亡和典型胚胎病变特征。HN毒株对热、乙醚和氯仿敏感,耐酸(PH3.0)、耐碱(PH11.0),能低抗1%胰蛋白酶,能在鸡胚中干扰鸡新城疫病毒La Sota株的增殖。试验结果表明,HN毒株的理化生支气管炎病毒相会。 相似文献
107.
施钾量对泗杂3号棉铃发育和纤维品质的影响 总被引:2,自引:0,他引:2
[目的]研究不同施钾量对棉铃发育和纤维品质的效应,旨在为该品种钾肥运筹提供措施依据。[方法]以泗杂3号为试验品种,研究施钾量对棉铃发育和纤维品质的影响。[结果]结果表明:施用适量的钾肥对棉铃发育和纤维品质的改善具有明显促进作用,主要表现为棉铃发育过程中棉铃体积、单铃子棉重、单铃纤维重增加速率较高,棉铃体积、单铃子棉重、单铃纤维重显著增加;纤维长度和长度整齐度有一定提高,比强度、麦克隆值和纺纱均匀性指数显著提高。[结论]综合棉铃发育和最终纤维品质,240 kg/hm2施钾量的促进效应最好。 相似文献
108.
Olav Fjeld Kraugerud Michael Penn Trond Storebakken Ståle Refstie Åshild Krogdahl Birger Svihus 《Aquaculture (Amsterdam, Netherlands)》2007,273(1):96-107
Duplicate groups of Atlantic salmon (Salmo salar), kept in saltwater, were fed fish meal based cold-pelleted diets where graded levels of native or extruded non-starch polysaccharides (NSP) from soybeans replaced cellulose, at a total NSP level of 100 g kg− 1 for 28 days. The study also included a diet where defatted soybean meal (SBM) constituted the NSP at a level of 100 g kg− 1 and a reference diet without NSP supplementation.The SBM diet resulted in a significant reduction in faecal dry matter content, apparent digestibilities of starch and organic material, and growth, and an increased faecal output of several elements (K, Na, Zn), compared to all the other diets. Morphological changes were only seen in the intestine of the fish fed the SBM, i.e. the diets holding purified soy-NSP did not induce enteritis. When compared to the diet without NSP, cellulose addition increased faecal dry matter, while inclusion of native soy-NSP reduced it. Dry matter in faeces and apparent digestibility of crude protein decreased in a linear manner, while the digestibility of starch and faecal output of K and Na increased linearly when native soy-NSP replaced graded levels of cellulose from 0 to 100 g kg− 1 feed. When diets with 75 or 100 g kg− 1 of native NSP and extruded soy-NSP were compared, fish fed native soy-NSP had reduced faecal dry matter, higher digestibility of starch, and increased faecal output of Cu, Fe, and K. Dry matter in faeces and faecal output of Cu was lower for the highest inclusion level, while digestibility of starch and faecal output of Mn and K were higher.In conclusion, soy-NSP was inert compared to the fish meal reference, with respect to nutrient digestibilities and intestinal pathologies, but affected faecal mineral excretion in Atlantic salmon. 相似文献
109.
江西省不同生态条件对棉纤维品质的影响 总被引:1,自引:1,他引:1
不同生态区棉纤维品质测定,是全国优质棉基地县建设科技服务中的一个专题研究项目,目的在于了解全国不同生态棉区影响纤维品质的主要因子。江西省通过七个试点两个品种连续三年的试验研究,结果表明:地点间差异显著,主要受气候因素的影响.2.5%的跨长与开花后1~18天的雨量、光照和20~25℃的适宜温度天数呈正相关,但决定系数不大;比强度与开花后19~25天的雨量和≥32℃的高温天数呈负相关,与该阶段光照呈正相关;马克隆值与开花后19~25天的雨量和收花前<16℃的低温天数呈负相关,与开花后26天至收花时的适宜温度(20~25℃)天数呈正相关。江西棉纤维偏粗主要与伏旱明显及持续高温有关,其次是土壤肥力差异.同一品种的棉纤维品质,以中、下部铃好于上部铃,正常年份好于灾年(或旱年),平原洲地棉区好于丘陵红壤旱地.说明因地制宜地选用良种和优化栽培措施,对提高棉纤维品质有着积极的指导意义。 相似文献
110.