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排序方式: 共有812条查询结果,搜索用时 30 毫秒
1.
介绍了天铁炼钢厂中间包水模实验原理和过程,分析了斜、直、圆三种型式挡渣墙模拟结果,提出了合理的挡渣控流方案,在生产实践中使用效果良好。 相似文献
2.
Ice recrystallization rates in simple aqueous solutions comprising fructose and a hydrocolloid stabilizer were measured. The stabilizers were an enzyme-modified guar and a non-gelling high methoxy pectin. The stabilizer concentration dependence of the recrystallization rates for both materials was similar in that increasing the concentration resulted in decreasing rates until a point is reached where further addition had no additional effect. That recrystallization rates were reduced by both gelling and non-gelling stabilizers was strongly suggestive that gelation was not a requirement for recrystallization inhibition and another more specific mechanism applies, for example a weak interfacial effect such as adsorption or blocking. This behavior was also seen with locust bean gum and guar and provided further empirical evidence to support the hypothesis that stabilizers adsorb to ice crystal surfaces. 相似文献
3.
采用客观仪器评价方法对含鲜奶面霜单次使用后的缓解皮肤红斑反应的功效进行研究。选择30名18~55周岁有效受试者为研究对象,使用胶带粘贴及组胺刺激构建皮肤红斑反应模型,并采用无创仪器的方式检测并记录实验组、安慰剂组、阴性组及空白组受试者在组胺造模前、造模后、涂抹产品后30 min和60 min时的皮肤红斑指数EI值、皮肤敏感度值,采集皮肤图像,通过SPSS数据统计软件对实验结果进行统计分析。结果显示,含鲜奶面霜可以持续改善皮肤红斑指数EI值和皮肤敏感度,缓解由组胺导致的皮肤红晕反应,说明其具有一定的缓解皮肤红斑反应,改善皮肤敏感状态的功能。 相似文献
4.
采用盐酸处理祛斑霜样品,用还原气化-原子荧光光谱法测定其中的汞,研究了仪器测定条件和不同样品处理方法对测定的影响。结果表明样品处理方法对测定结果影响不大;此方法的加标回收率在96%以上,相对标准偏差为2.5%;此方法具有快速、简便和灵敏的特点。 相似文献
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陈毅俊 《重庆电力高等专科学校学报》2012,17(1):37-39,42
快速阅读是大学英语六级考试改革以来采用的新题型,考试大纲中明确规定了略读与寻读策略的具体要求及其使用的必要性。因此,在经过大学英语四级快速阅读的考试实践和一年的大学英语阅读学习后,准备参加六级的学生们在进行快速阅读时究竟采用了何种策略,是否把略读与寻读技巧作为他们策略的首选,对这两种策略掌握的程度如何,这些问题将是本研究的关键。 相似文献
9.
陈莹 《浙江纺织服装职业技术学院学报》2005,4(3):14-17
纳西族女性羊皮披肩是纳西族传统服饰中的精华.文章除了对羊皮披肩从材质、色彩、造型、装饰要素在形式美感和实用功能层面的阐述之外,还深入到服饰文化内涵的层面进行分析,提出了在面对现代文明的撞击和多种文化交融的情形下,承载着纳西族服饰文化传统的羊皮披肩仍然焕发着特有的魅力和强大的生命力,但我们必须要树立保护传统服饰文化精粹的意识,通过研究与挖掘,让其延续的同时将其发扬光大. 相似文献
10.
《Food Control》2017
Listeriosis is an invasive illness typically caused by the ingestion of foods contaminated with Listeria monocytogenes. In 2015, an outbreak of listeriosis was linked to ice cream products produced on a specific production line at Facility X. The United States Food and Drug Administration (FDA) obtained samples representing several lots of three products manufactured on that line from May 2014 through January 2015. Two of these products, A and B, while not linked to any reported illnesses, were analyzed to determine the frequency of contamination and the contamination level for risk assessment and dose-response analyses. These enumerations were performed utilizing a Most Probable Number (MPN) method, with a lower detection limit of 0.03 MPN/g, on 344 samples of Product A and 95 samples of Product B. Ten lots of Product A were analyzed and 77% of the samples tested were found to be positive for L. monocytogenes. Five lots of Product B were analyzed and 46% of the tested samples were found to be positive. Additionally, the level of contamination of positive Product B samples was always less than 1 MPN/g. The contamination levels of both products, overall, were low with median values of 0.1 MPN/g and 0.02 MPN/g for Products A and B, respectively. A majority of Product A samples (52%) were contaminated at levels of less than 1 MPN/g and only one sample was above 100 MPN/g. Whole genome sequencing (WGS) of L. monocytogenes isolated from ice cream samples produced in the line suggested minor strain differences related to product type, possibly due to differences in the food matrices and/or differences in the manufacturing equipment. Overall, the data showed a consistent low level of contamination in products produced from a single production line over a nine month period. 相似文献