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101.
2400高强瓦楞原纸机流浆箱是根据瓦楞纸浆容易产生浮浆、泡沫及絮聚的流送特性,对其布浆、扩散、整流及结构从流体力学的角度进行了探讨,认为该流浆箱使用在抄速150m/min左右的纸机上,完全可以获得良好的、稳定的扩散浆流。  相似文献   
102.
本研究以虾头为原料,通过酶解、阴离子交换树脂、醇沉的方法提取并分离纯化了虾头中的类肝素;采用乙酸纤维素薄膜电泳初步鉴定了纯化后类肝素的种类,通过紫外吸收光谱、高效凝胶渗透色谱分析其纯度和分子质量,通过傅里叶变换红外光谱分析其官能团结构,采用柱前衍生化高效液相色谱分析其单糖组成;并通过体外凝血实验研究了其抗凝血活性.结果...  相似文献   
103.
分析黄鳍金枪鱼、大眼金枪鱼和马苏金枪鱼鱼头不同部位(鱼肉、鱼皮和鱼骨)的基本营养成分,并评价其营养价值。结果表明:3 种金枪鱼鱼头均含有丰富的粗蛋白、粗脂肪和灰分;3 种金枪鱼鱼头的鱼肉中必需氨基酸种类齐全,必需氨基酸与总氨基酸含量的比值接近40%,氨基酸评分较高,必需氨基酸指数大于86,属于优质蛋白;而鱼皮和鱼骨中蛋白质的营养价值相对较低;3 种金枪鱼鱼头的脂质中饱和脂肪酸、单不饱和脂肪酸、多不饱和脂肪酸的比例接近于1∶1∶1,富含二十二碳六烯酸(docosahexaenoic acid,DHA)和二十碳五烯酸(eicosapentaenoic acid,EPA),其含量分别为15.69%~23.29%和4.02%~5.15%,DHA与EPA的比值为3.23~5.27,n-6与n-3多不饱和脂肪酸的比值为0.13~0.29,具有较高的营养价值;3 种金枪鱼鱼头中还富含对人体健康有益的Ca、Fe、Zn等矿物质元素。  相似文献   
104.
Sunflower Head Residue Pectin Extraction as Affected by Physical Conditions   总被引:2,自引:0,他引:2  
Effects of extraction pH, temperature, and time on yield and quality of pectin from sunflower heads (Interstate cultivar) were investigated. The low-methoxyl pectin was extracted, using 0.75% sodium hexametaphosphate at pH 3, 4, and 5 and at 75, 85, and 95°for 20, 40, and 60 min, respectively. Yield, molecular mass, and firmness of jellies of the pectins were determined. Three-way statistical analysis on yield, molecular mass and gel firmness showed strong interactions among pH, temperature and time. Highest yields were obtained at pH 5, 95°for 20 min and pH 4, 85°for 40 min. Pectin extracted for 40 min at pH 3 and 4 and at 85°and 75°C, respectively, had the highest molecular mass. Gel firmness of sunflower pectin prepared at pH 5.4 was higher than that of a commercial citrus pectin.  相似文献   
105.
Two methods, the “Rudin” method and the “Nibem” method have been tested for the determination of foam stability of beer by the Analysis Committee of the Institute of Brewing . For the Rudin method, over the range 90 to 102 seconds, it was judged that precision values were independent of the foam stability of the sample. Values for r95 and R95 were 6 and 22 seconds, respectively . For the Nibem method, precision was also independent of the foam stability of the sample over the range 213 to 246 seconds. Values for r95 and R95 were 22 and 70 seconds, respectively . The two methods ranked the foam stability of the three beers tested differently. This is to be expected, bearing in mind the different principles of the two procedures .  相似文献   
106.
对在配置偏置式激光头的激光加工机上实现单点指向功能进行了探讨.为保证激光加工的高速和稳定性,提出分别为程序控制和手控盒控制设计独立的单点指向补偿器P和J的思想,并分析了各自补偿器的实现方法.同时,为了保证单点指向功能的有效实现,还进行了粗插补精度的计算.  相似文献   
107.
The current study presents the results of a survey performed to investigate whether different patterns of foam and lacing affect consumer beer preference and the perception of beer characteristics. The impact of three different levels of foam (huge, medium and little) at pouring, and two lacing patterns (very laced to not laced) during consumption, was evaluated on a set of 26 attributes by a panel of Italian beer consumers. Overall, beers which delivered a medium level of foam at pouring were considered by Italian consumers as the best dispensed, the most liked for their visual appearance, the most attractive to consume and the most likely to be purchased. Cluster analysis determined four groups of consumers with different preference patterns for beer foam and expectations for sensory characteristics of the beer. It was found that 80% of consumers preferred a medium level of foam and no lacing, whereas 20% of consumers preferred a high level of foam and lacing. Furthermore, for nearly 40% of consumers, foam and lacing patterns generated expectations regarding beer sweetness, bitterness, fruitiness, perceived level of alcohol, effervescence and the thirst quenching character of the beer.  相似文献   
108.
109.
We investigated the growth behavior and amylolytic enzymes of Fusarium graminearum cultivated on different types of native starch granules including barley (A‐type crystalline polymorph), potato and Curcuma zedoaria (B‐type crystalline polymorph), cassava (C‐type crystalline polymorph), and high AM maize (A + Vh‐type crystalline polymorphs). F. graminearum grew poorly on B‐type starches and the accumulation of biomass was similar to that obtained for fungi cultivated under carbohydrate starvation conditions. In comparison, three‐ to fivefold higher accumulation of fungal biomass was observed for growth on the A‐, C‐ and A + Vh‐type starches. Fungal glucoamylase and α‐amylase activity increased over time in the presence of native starch granules. Interestingly, resistant B‐type starches induced the highest amylolytic activity indicating that F. graminearum interacts with B‐type granules although only limited degradation occur. Starch degradation products maltose and malto‐oligosacharides was found to increase glucoamylase and α‐amylase activity, whereas glucose acted as a catabolite repressor.  相似文献   
110.
对斑点叉尾鮰鱼头和鱼头酶解物干燥粉的风味成分进行了分析和比较,研究结果表明,斑点叉尾鮰鱼头和鱼头酶解物中都含有丰富的氨基酸和核苷酸。相对于新鲜的斑点叉尾鮰鱼头,鱼头酶解物中的风味氨基酸、游离氨基酸和核苷酸的含量都更高。斑点叉尾鮰鱼头酶解物中含有对风味贡献比较大的钾、钙、钠、镁等无机元素,而有害的铅、汞等重金属元素的含量均低于国家标准规定。对新鲜的斑点叉尾鮰鱼头、鱼头酶解物的挥发性风味成分分析结果表明,鱼头在酶解时产生了大量风味物质。在斑点叉尾鮰鱼头酶解物检测发现34种挥发性成分,其中呈现风味的主要成分之一杂环类化合物含量达到85.09%,使得鱼头酶解物干燥粉具有远高于新鲜鱼头的浓郁鱼香味。此实验结论可为斑点叉尾鮰鱼头的利用提供一定理论依据。  相似文献   
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