11 research outputs found

    distributed multimedia database systems

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    着重分析分布式多媒体数据库系统的特有问题,包括实时性、时空同步以及服务质量的描述与实现等.给出了解决这些问题的策略和方法.研究了各种不同的实现途径--远程调用、中间件和Agent构造的方式;指出了这些实现方法的优点及其不足

    尺寸均一的生物微球和微囊的设计、制备和应用研究

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    高分子微球在生物技术和生物医药技术领域有着重要的应用,尤其在药物缓控释载体、生物分离介质、酶固定化载体、细胞培养载体以及人工器官等方面得到了广泛的应用。例如, 壳聚糖微球由于具有生物黏附性和生物相容性,包埋药物后可用于口服给药和鼻腔粘膜给药; 高分子多孔微球因其高比表面积在天然产物的分离纯化中显示了优越性;琼脂糖微球由于其特殊的凝胶网络结构和对蛋白质不显示非特异性吸附的性能,在蛋白质分离应用方面取得了</p

    颗粒流体两相流动的随机分析

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    研究提示颗粒流体两相流动随机特征的方法.通过对流体中影响颗粒运动的各种复杂作用进行分类处理,提出了一种新的离散颗粒随机模拟方法.初步的模拟计算获得了与实验测量一致的颗粒时均速度、脉动速度、局部平均粒径和颗粒浓度等总体宏观统计特征,以及经过空间某一位置的颗粒速度、粒径随时间的动态变化行为和颗粒流动的不均匀空间分布结构特征等丰富的信息

    颗粒流体两相流动的随机分析

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    研究揭示颗粒流体两相流动随机特征的方法,通过对流体中影响颗粒运动的各种复杂作用进行分类处理,提出了一种的离散颗粒随机模拟方法,初步的模拟计算获得了与实验测量一致的颗粒时均速度、脉动速度、局部平均粒径和浓度等总体宏观设计特征,以及经过空间某一位置的颗粒速度、粒径随时间的动态变化行为和颗粒流动的不均匀空间分布结构特征等丰富的信息

    颗粒流体两相流动的随机分析

    No full text
    研究揭示颗粒流体两相流动随机特征的方法,通过对流体中影响颗粒运动的各种复杂作用进行分类处理,提出了一种的离散颗粒随机模拟方法,初步的模拟计算获得了与实验测量一致的颗粒时均速度、脉动速度、局部平均粒径和浓度等总体宏观设计特征,以及经过空间某一位置的颗粒速度、粒径随时间的动态变化行为和颗粒流动的不均匀空间分布结构特征等丰富的信息

    聚二乙烯基苯微球介质制备及其在奥曲肽层析分离中的应用

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    以二乙烯基苯为单体,采用微孔膜乳化法制备了尺寸均一的水包油乳液,在75℃下悬浮聚合20 h,制得均一的聚二乙烯基苯微球填料,粒径为14.2 μm,粒径分布系数R_(span)=0.71,孔径为65 nm,比表面积为160 m~2/g. 通过高压匀浆法将合成的微球介质高效装填不锈钢液相色谱柱(φ4.6 mm×250 mm),使柱效达11000塔板数. 利用装填的色谱柱进行多肽药物奥曲肽的分离纯化,奥曲肽从固相合成粗品中快速有效分离,纯度由42.89%提高到99.99%

    聚二乙烯基苯微球介质制备及其在奥曲肽层析分离中的应用

    No full text
    以二乙烯基苯为单体,采用微孔膜乳化法制备了尺寸均一的水包油乳液,在75℃下悬浮聚合20 h,制得均一的聚二乙烯基苯微球填料,粒径为14.2 μm,粒径分布系数R_(span)=0.71,孔径为65 nm,比表面积为160 m~2/g. 通过高压匀浆法将合成的微球介质高效装填不锈钢液相色谱柱(φ4.6 mm×250 mm),使柱效达11000塔板数. 利用装填的色谱柱进行多肽药物奥曲肽的分离纯化,奥曲肽从固相合成粗品中快速有效分离,纯度由42.89%提高到99.99%

    聚二乙烯基苯微球介质制备及其在奥曲肽层析分离中的应用

    No full text
    以二乙烯基苯为单体,采用微孔膜乳化法制备了尺寸均一的水包油乳液,在75℃下悬浮聚合20 h,制得均一的聚二乙烯基苯微球填料,粒径为14.2 μm,粒径分布系数R_(span)=0.71,孔径为65 nm,比表面积为160 m~2/g. 通过高压匀浆法将合成的微球介质高效装填不锈钢液相色谱柱(φ4.6 mm×250 mm),使柱效达11000塔板数. 利用装填的色谱柱进行多肽药物奥曲肽的分离纯化,奥曲肽从固相合成粗品中快速有效分离,纯度由42.89%提高到99.99%

    Dynamic characteristics of soil respiration of Savanna ecosystem in dry hot valley of Yuanjiang

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    [Objective] Soil respiration plays an important role in regulating CO_2 concentration in the atmosphere.Soil respiration in the Savanna ecosystem is one of the main sources of global greenhouse gas emissions,but its emission characteristics and main influencing factors are not clear.[Method] Taking the Savanna ecosystem in dry hot valley of Yuanjiang inYunnan Province as an example,the soil respiration was measured from June 2014 to June 2015 by static chamber method,and the dynamic characteristics and its influencing factors in the Savanna ecosystem in Yuanjiang were studied.[Result] Soil temperature,soil moisture and soil respiration had obvious seasonal variations,and as expected,they were significantly(P<0.01)higher in rainy season than in dry season.The relationship between soil respiration and soil temperature and soil moisture are exponential and parabola.The temperature Q_(10) at 5 and 10 cm of soil was 1.73 and 1.98 respectively,which was less than the global average of 2.0.Therefore,using 10 cm soil temperature could better simulate soil respiration.Fitting analysis of soil temperature,water content and soil respiration showed that the soil respiration of Savanna ecosystem in Yuanjiang was mainly restricted by water condition.The annual emission of soil respiration in the ecosystem was 4.20 t·hm~(-2)·a~(-1),including 2.71 t·hm~(-2) in rainy season,accounting for 64.5% of the total annual carbon emission,and 1.49 t·hm~(-2) in dry season,accounting for 35.5% of the total annual carbon emission.The average value of soil respiration in global Savanna ecosystem is 8.16 t·hm~(-2)·a~(-1).[Conclusion] Compared with the global Savanna ecosystem,the total amount of soil respiration in Yuanjiang was in a lower position,which could be attributed to the lower rainfall in the Savanna ecosystem in Yuanjiang.There exists a significant positive correlation between rainfall and soil respiration in the Savanna region(R~2=0.61,P<0.001)
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