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81.
从配方和工艺2 个角度研究颗粒型燕麦牛乳的稳定性,以离心沉淀率、黏度和感官评分作为评价指标。结果表明:对稳定剂进行优化后,得到最佳复配稳定剂配方为结冷胶添加量0.04%、卡拉胶添加量0.020%、羧甲基纤维素钠添加量0.020%、微晶纤维素添加量0.20%;对配料温度、水合时间、均质压力和灌装温度4 个影响体系稳定性的工艺点进行单因素试验,继而设计正交试验,得到最佳参数组合为配料温度50 ℃、水合时间40 min、均质压力30 MPa、灌装温度15 ℃,此条件下产品稳定性最佳,口感良好。 相似文献
82.
具有抗氧化活性的猪血浆蛋白酶解产物的制备及理化特性 总被引:1,自引:0,他引:1
为系统考察酶解时间、酶种类和酶加入的顺序对猪血浆蛋白酶解产物抗氧化性的影响,采用风味蛋白酶、碱性蛋白酶及双酶(风味蛋白酶,碱性蛋白酶不同的加入顺序)在各自最适条件下对猪血浆蛋白进行酶解,并研究酶解产物的功能特性。结果表明:0~120min内,随着酶解时间的延长,水解度升高,各酶解产物的抗氧化性均有所增强;60~180min内,双酶酶解产物的清除DPPH自由基的能力、亚铁离子螯合能力和还原力显著高于单酶酶解产物(P0.05);90~150min内,先加碱性蛋白酶后加入风味蛋白酶酶解的酶解产物的水解度、清除DPPH自由基能力和还原力显著高于先加风味蛋白酶酶解后加入碱性蛋白酶酶解的酶解产物(P0.05);具有较高抗氧化性的酶解产物在不同pH条件下均有较好的溶解性和热稳定性;溶解性均在90%以上。 相似文献
83.
为研发高效、精准的监测防控设备,利用八臂行为选择装置系统测定不同光源、性别和光处理时间下草地贪夜蛾Spodoptera frugiperda的趋光行为。结果显示,在紫外光(波长365 nm)、紫光(波长420~430 nm)、蓝光(波长465~475 nm)、绿光(波长525~535 nm)、黄光(波长585~595 nm)和红光(波长655~665 nm)6种波长光源下,草地贪夜蛾混合种群(雌雄成虫比为1∶1)对紫外光光源的趋光选择率最高,为25.61%,显著高于其他处理,其次为紫光和蓝光光源,趋光选择率分别为16.30%和8.82%,对红光的趋光选择率最低,为4.76%。在紫外光刺激下,草地贪夜蛾雌成虫的趋光选择率显著高于混合种群(雌雄成虫比为1∶1),在红光刺激下,雄成虫的趋光选择率显著高于雌成虫。另外,在紫外光刺激下,光处理时间60 min草地贪夜蛾雌成虫的趋光选择率显著高于其他处理。表明光源与性别因素均影响草地贪夜蛾的趋光行为,光处理时间对草地贪夜蛾的趋光行为影响较小,且与光源及性别因素有关。 相似文献
84.
C. Le Guillou D. A. Angers P. Leterme S. Menasseri‐Aubry 《Soil Use and Management》2012,28(4):590-595
There is a need to develop practices that contribute to increased water‐stable aggregation (WSA) during winter in a humid temperate climate when soil is particularly prone to water erosion. Our objectives were to determine the effects of crop residue quality on WSA during winter and to relate these effects to biochemical indicators of fungal and bacterial biomass. Three graminae crop residues were selected for their different C/N ratios and biochemical characteristics (green oat residues, C/N = 18.8; wheat straw, C/N = 125.6; and mature miscanthus residues, C/N = 311.3). In October 2009, crop residues were added with an equivalent amount of C in the 0–10 cm layer to a Luvisol in north‐west France. WSA, expressed as mean weight diameter (MWD), amino sugar, soil mineral N and water contents were measured at regular intervals during 5 months. Aggregate MWD of the control soil decreased rapidly and remained low until the last sampling date in March which illustrates the structural vulnerability of bare soils in winter in this pedo‐climatic area. The incorporation of all three crop residues had significant positive impacts on aggregate MWD. Despite widely different C/N ratios, the maximum MWD under each treatment was similar (three times greater than the control soil). Maximum MWD occurred at times that clearly depended on residue quality. Maximum values occurred early for green oat (29 day), but were delayed to 50 day for wheat straw and to 154 day for miscanthus. Results from correlation analysis suggest that variations in WSA were partly mediated by microbial agents with a dominant effect of bacteria for green oat and a combined role of fungal and bacterial biomass for wheat straw. We suggest that the maximum MWD associated with the miscanthus late in the experiment is related to changes in the composition of the fungal community. Overall, our study shows that autumn application of crop residues increases WSA during winter with its effect being microbially mediated and determined by residue quality. 相似文献
85.
通过对一维Theta-神经元网络中细胞耦合作用时间的讨论,得到较长时间的耦合作用时间会使网络中单放电行波变为多放电行波,并通过数值模拟对理论加以验证. 相似文献
86.
为解决泰州大佛指银杏加工季节限制,获得一款口感宜人、稳定性良好的保健型饮料,以全银杏粉为主要原料,通过模糊数学法结合正交试验优化全银杏粉饮料的最佳配方,采用功效系数法结合正交试验优化全银杏粉饮料稳定剂的最佳复配比,以均质压力和均质温度对全银杏粉饮料稳定性的影响确定最佳均质条件。结果表明,全银杏粉饮料的最佳配方为:全银杏粉初汁添加量80%,低聚果糖添加量10%,柠檬酸添加量0.10%,蜂蜜添加量0.10%;稳定剂最佳复配比为:微晶纤维素(MCC)0.15%,卡拉胶0.20%,海藻酸丙二醇酯(PGA)0.20%;最佳均质条件为:均质压力40 MPa,均质温度60 ℃。 相似文献
87.
[目的]研究不同类型水稻品种产量构成因素与产量的关系,为水稻高产栽培提供理论依据。[方法]以在四川成都地区应用较多的超级稻品种和非超级稻品种为试验材料,研究不同类型品种连续 3 年(2006~2008 年)在高产栽培条件下的产量表现,分析其产量构成因素与产量的关系。[结果]水稻的产量与穗数、穗粒数、结实率、千粒重关系密切,对于不同的品种类型,4个因素对产量的影响存在差异。在10.5~11.25 t/hm2的产量目标下,通过中小苗三角形条栽模式研究结果显示超级稻的产量与穗数、千粒重关系密切,同时,与穗粒数呈负相关,与结实率呈显著负相关。非超级稻品种的产量与穗数、穗粒数、结实率、千粒重均呈负相关关系,且与穗数、千粒重呈显著负相关。[结论]该研究明确了不同类型水稻品种的产量构成因素与产量的关系,为合理制订高产栽培措施、充分发挥超级稻的产量潜力、实现水稻大面积稳产高产奠定了基础。 相似文献
88.
将甜橙果汁与牛乳调和,通过单因素试验,对稳定剂成分、酸味剂配比、杀菌条件进行确定,然后通过L9(34)正交试验对主要原料配比、稳定剂各成分配比进行研究。结果表明,原橙汁20%,脱脂乳粉3%,蔗糖10%,柠檬酸0.25%,乳酸0.025%,高黏度CMC0.25%,PGA0.1%,高脂果胶0.20%,80℃下杀菌15min,可制作出质量和风味俱佳的甜橙牛乳酸性饮料。 相似文献
89.
隧洞内衬钢板灌胶加固技术是在钢筋混凝土隧洞内壁通过植锚栓的方式安装薄钢板,而后在钢板与混凝土接触面之间灌注结构胶,使钢板与混凝土共同受力,满足钢筋混凝土隧洞结构加固的需要。在灌注结构胶的过程中,由于外部灌注压力的作用,薄钢板抗外压失稳问题将受到特别的关注。通过具体工程实例,详细介绍了薄钢板抗外压稳定计算的几种方法。 相似文献
90.
Ebling PM 《Pest management science》2004,60(7):631-638
The biological activity of the Ireland strain of Choristoneura fumiferana (Clem) nucleopolyhedrovirus (CfMNPV) propagated in different hosts was determined to provide the basis upon which genetically modified CfMNPV, or other naturally occurring isolates, should be compared. Occlusion bodies (OB) derived from CF-203 cells were significantly larger and more pathogenic than those propagated in vivo when tested against the fifth larval instar of C fumiferana (Clem) and C occidentalis Freeman. The dose-responses (LD50 and LD95, expressed as occlusion bodies per larva) of C fumiferana larvae to in vitro-propagated OBs were 274 and 5785, respectively. The values of LD50 and LD95 to C occidentalis larvae were 19 and 118, respectively. There were no significant differences in pathogenicity or size when OBs propagated in C fumiferana larvae were tested against either insect species, nor were there significant differences for OBs propagated in C occidentalis larvae. The LD50 and LD95 of in vivo-produced OBs to C fumiferana were 925 and 61988, respectively. The LD50 and LD95 to C occidentalis were 50 and 453, respectively. OBs propagated in vitro had a mean volume of 13.13 microm3, whereas those propagated in vivo ranged from 0.84 to 1.41 microm3. The median survival time-responses (ST50) of fifth-instar C fumiferana or C occidentalis larvae to OBs propagated in vivo were not significantly different from those propagated in vitro at the dosage levels tested. Values of ST50 of C fumiferana larvae to in vitro- and in vivo-produced OBs at dosages causing less than 50% mortality rangedfrom 9.6 to 9.8 days post-inoculation (dpi), whereas a LD95 dose resulted in ST50 values ranging from 7.3 to 7.7 days. ST50 values of C occidentalis larvae at dosages causing less than 50% mortality ranged from 9.8 to 10.2 dpi, whereas a LD95 dose resulted in ST50 values ranging from 9.5 to 9.8 dpi. The median feeding cessation time-response (FT50) of fifth-instar C fumiferana larvae to OBs propagated in vitro (5.7 days) was not significantly different from the FT50 of those propagated in vivo in either insect species (5.3 and 5.7 days) at the dosage level tested (LD95). No significant differences in FT50 values were observed between OBs propagated in either larval host. The FT50 of C occidentalis larvae to OBs propagated in vitro (7.7 days) was not significantly different from that to those propagated in vivo in C occidentalis larvae (7.6days), but somewhat different (7.2 days) from that to those propagated in C fumiferana larvae. Results indicate that CfMNPV can be propagated in vivo in either C fumiferana or C occidentalis larvae (or sequentially through both) without alteration in infectivity, although the use of the CF-203 cell line yields the most biologically active OBs. 相似文献