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11.
Kim Sam Soo Leem Su Gyung Ghim Han Do Kim Joon Ho Lyoo Won Seok 《Fibers and Polymers》2003,4(4):204-209
The effect of padding solution on the microwave heat dyeing of polyester fabric was studied extensively. Polyester fabrics
were impregnated in aqueous urea solution and aqueous sodium chloride solution for 10 min and then dyed for 7 min by microwave
apparatus (2 450 MHz, 700 W) under optimum conditions which provide good exhaustion. Aqueous solutions of urea and sodium
chloride showed more effective than water as a padding solution for microwave heat dyeing. The type of solvent added in padding
media and its concentration significantly affects the K/S values of dyed polyester fabric. Added solvents such as n-hexane,
acetone, and dimethyl formamide were also more effective than 100% water as padding media for the microwave heat dyeing. It
is supposed that the effect of used solvents on dyeing property of polyester fabrics depends on the solubility parameter difference
between solvent and polyester fabric. 相似文献
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微波法提取杨桃渣中多酚的工艺研究 总被引:3,自引:0,他引:3
[目的]研究微波法提取杨桃渣中多酚的工艺条件。[方法]利用微波提取法,通过单因素研究了5个因素对杨桃多酚提取率的影响,并通过正交试验筛选提取杨桃渣多酚的最佳工艺条件。[结果]单因素试验表明,物料粒径30目,微波功率560W、60%乙醇浓度、料液比1:50、提取时间60S、提取2次可得到从杨桃渣中提取多酚的最佳效果。正交试验表明,4因素对微波提取杨桃渣多酚的影响顺序为溶剂浓度〉料液比〉提取时间〉功率;微波法从杨桃渣中提取多酚的最佳工艺条件为:乙醇浓度50%、物料颗粒30目、液料比1:70、微波功率700W、提取时间60S,在此条件下从杨桃渣中提取的多酚浓度可达18.725mg/g。[结论]微波辅助萃取具有提取率更高、所需时间短的特点.应用前景广阔 相似文献
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饱和土壤冻融过程中水热迁移数值模拟 总被引:4,自引:0,他引:4
利用土壤冻融过程的水热传输方程,模拟了饱和土壤冻融的年变化过程,分析了土壤冻结深度的年变化规律和水分向冻结界面迁移的特征。同时亦对影响土壤冻结深度的温度因子做了探讨。 相似文献
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AIM: To investigate the effect of microwave radiation at different intensities on the rat myocardium and its possible mechanism.METHODS: The rats were radiated by the intensity of 500, 1 000, 1 500 and 2 000 W/m2 with 2 450 MHz microwave for 6 min. The heart tissue was collected 6 h after microwave radiation. ATP and mitochondria complex Ⅳ and Ⅴ were measured. The changes of the tissue structures were observed under transmission electron microscope. The apoptosis of the myocardial cells was detected by a cell analyzer. The protein level of cleaved caspase-3 was determined by Western blotting.RESULTS: The concentration of ATP and activity of mitochondria complex Ⅳand Ⅴ signi-ficantly decreased compared with control group in the cardiac tissues. The decreased number, morphological abnormalities such as dissolved cavitation, matrix and obvious tumefaction of mitochondria were observed under transmission electron microscope. The microwave radiation induced the apoptosis of myocardial cells in the rats. The cell apoptotic rate and the protein level of cleaved caspase-3 increased with increasing intensity of microwave radiation(P<0.05).CONCLUSION: Microwave radiation has obvious injury effect on the rat heart, which can cause cardiac energy metabolism dysregulation and cardiac myocyte apoptosis. 相似文献
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In order to make male flower tea of Eucommia ulmoides, this paper systematically investigated the effects of microwave drying, a newly emerging drying method, on the contents of functional constituents contained in the flower (such as total flavonoids, chlorogenic acid, aucubin and geniposidic acid) from the aspects of microwave output power and time of treatment. A comparison was conducted in the view of tea quality between microwave drying and conventional drying methods used in tea manufacturing, such as pan baking drying and oven ventilation baking drying. The results indicated that microwave drying method could maximally maintain the functional constituents. Further comparison on sensory quality showed that by microwave drying mode, the shape of the stamens of the flower was intact, the color was greenish, the liquor of the flower tea was fresh with strong Eucommia male flower flavor. 相似文献
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用 IRIS Intrepid II XSP ICP全谱直读等离子体发射光谱仪,对黄山名茶中 Se、Fe、Mn、Cd、Cr、Co、Ni、Cu、Pb、Zn等微量元素进行了测定,通过试验,选择了仪器的最佳分析条件。方法简便快速,精密度和准确度均符合要求。该方法用于实际茶叶样品分析,结果令人满意。 相似文献