排序方式: 共有17条查询结果,搜索用时 15 毫秒
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以70%乙醇为提取溶剂,超声提取温度为60℃,料液比为1:30,采用先浸泡再水浴加热后超声的方法提取通经草不同部位的总黄酮,然后通过小鼠耳肿胀实验,比较通经草不同部位的抗炎作用。结果表明,通经草根中总黄酮的含量为2.37%,茎中总黄酮的含量为3.05%,叶中总黄酮的含量为5.10%。通经草不同部位高、中剂量提取液均能显著抑制二甲苯致小鼠耳廓肿胀,与阴性对照组比较有显著性差异(P<0.01)。表明通经草有显著的抗炎作用,抗炎作用强弱依次为叶>茎>根。 相似文献
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以甲基丙烯酸为原料,N ,N’亚甲基双丙烯酰胺为交联剂,过硫酸钾为引发剂,自由基引发聚合制备聚甲基丙烯酸水凝胶,研究了聚甲基丙烯酸水凝胶的溶胀率、保水率,讨论了交联剂、引发剂的用量以及pH、盐溶液浓度对溶胀性能的影响.实验结果表明:当合成温度为70℃时,p H=8,盐溶液浓度为0,交联剂、引发剂用量分别为反应物质量的0.6%,1.0%,制备出来的水凝胶的溶胀性能最好. 相似文献
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膨胀土地基处理有桩基、宽散水保湿暗沟等多种常规处理方法,经过综合比较和分析,本文着重介绍了地基帷幕结合宽散水的方法进行膨胀土处理,并将处理前后的地基变形计算进行了比较. 相似文献
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结合南水北调中线一期工程,对南阳膨胀岩土的野外特征、时代成因、膨胀特性及判定与分类标准做了描述和定性与定量的分析,提出了膨胀岩土的判定与分类中的时空性及判别与分类的方法。 相似文献
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以二步水溶液分散聚合法制备了具有温度及pH值双重响应性能的核-壳单分散纳米微凝胶,对微凝胶的形态、结构及粒径分布进行了表征,并采用动态光散射对其溶胀性能进行了研究,发现高度溶胀的P4VP壳层会对核的充分溶胀带来一定限制,并使其溶胀率下降. 相似文献
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研究了珍珠岩、米糠、木屑3种蓬松剂对米饭固体培养基的影响,采用可见分光光度计分别测定3种蓬松剂的吸光度值,同时测定3种蓬松剂与米饭混合后的吸光度值.结果表明:在3种蓬松剂样品中,米糠对米饭固体培养基的吸光度影响较大,与对照差异有统计学意义;木屑的影响较小,与对照差异较小;珍珠岩的影响最小,与对照差异无统计学意义,是最佳蓬松剂. 相似文献
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为了解青海省春小麦Glu-1位点的遗传多样性及其品质状况,检测了49个青海省代表性春小麦品种的高分子量麦谷蛋白亚基(HMW-GS)组成情况,并测定了每一品种的谷蛋白溶胀指数.共检测出15种高分子量麦谷蛋白亚基组合类型.在Glu-1位点检测到13种等位变异,其中Glu-A1位点2个、Glu-B1位点7个、Glu-D1位点4个.实验数据表明,青海省春小麦品质较差,尚待改进. 相似文献
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In a parallel study, it has been shown by comparison of successive TV-holography campaigns that murals in the convent of Müstair (Switzerland) have progressively detached from their substrate over a time interval of 5 years (J Cult Herit 2009). Here, we focus on the dynamics of the ongoing detachment processes. In order to regularly measure small surface displacements in situ over a long duration of several years, a new method that we call Mirror Micrometry (MM) has been designed and implemented. This method monitors the reflection of a light beam by a mirror that is mounted to the surface of interest for the duration of the experiment. The mirror is designed to rotate about a pivot as small displacements in the detaching surface occur, thus deflecting the reflected light beam. Measurements over more than three years in the Convent Church and in the Holy Cross Chapel reveal various types of surface displacement perpendicular to the wall surface. These are correlated with relative humidity (RH) changes in the room climate. Reversible short-term variations of approximately ±5–10 μm occur with periods of one to several weeks and relate primarily to weather changes. Reversible long-term variations of ±5–10 μm correspond to averaged seasonal humidity changes. Irregular and irreversible movements in increments of 20–30 μm record very localised progressive detachment steps. A semi-quantitative correlation of approximately 1 μm surface displacement per 1% RH change is calculated. Based on the fact that nearby measuring points can simultaneously move in opposite directions, a geometric model is drawn to explain deformation by hygric swelling and shrinking of different shapes of detached layers. 相似文献