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不同产地蜂胶中总黄酮的提取及含量测定 总被引:1,自引:0,他引:1
目的:测定不同产地蜂胶中总黄酮的含量,为蜂胶的质量控制提供更多依据。方法:通过正交设计试验,优选蜂胶中总黄酮的提取方法;以芦丁为对照品,用分光光度法测定不同产地蜂胶中总黄酮的含量。结果:国内主要产地的蜂胶中总黄酮含量均高于巴西蜂胶,且河南,山东产蜂胶中总黄酮含量大于20%。结论:该方法可靠,测定结果能反映客观实际,可作为蜂胶质量控制指标之一。 相似文献
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目的建立A群脑膜炎球菌荚膜多糖(Group A meningococcal polysaccharide,GAMP)排溢法ELISA,并进行验证及初步应用。方法采用改良过碘酸盐氧化法制备抗GAMP-HRP。以抗GAMP单克隆抗体包被酶标板,抗GAMP-HRP作为酶标抗体,建立检测GAMP的排溢法ELISA。采用棋盘滴定法确定包被抗体及酶标抗体的最佳工作浓度,并对其特异性、敏感性及重复性进行验证。采用建立的排溢法ELISA检测GAMP-TT系列层析样品中的GAMP抗原活性,并与传统一步法ELISA及二步法ELISA进行比较。结果建立的排溢法ELISA的包被抗体最佳浓度为20μg/ml,酶标抗体最佳工作浓度为1∶128。该方法的特异性良好,敏感性与一步法和二步法相当,批内和批间变异系数与一步法相当;该方法检测GAMP-TT层析样品中的GAMP抗原活性的结果与二步法ELISA基本一致。结论排溢法ELISA的操作步骤与一步法ELISA大致相似,但较二步法ELISA显著简化,其对一步法ELISA中Hooks效应的纠正效果与二步法ELISA相同。 相似文献
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目的探讨超氧化物歧化酶(SOD)的固定及固定化SOD活性的检测方法。方法以淀粉为载体,对SOD进行固定,采用改进的邻苯三酚测活法(以Vc为终止剂),并结合过滤或离心的方法去除沉淀,测定固定化SOD的活性。比较过滤法与离心法,及过滤法与经典邻苯三酚法测定酶活性的差异,并检测过滤法的线性、精密性和准确性。结果过滤法检测SOD活性的精密性较离心法高,与经典邻苯三酚法检测结果差异无统计学意义,在SOD浓度为6~60μg/ml范围内,SOD活性值与浓度线性关系良好(r=0.999 5),精密性及准确性良好。固定化SOD的比活性为1 730.07 U/g,酶活回收率为53.3%。结论以淀粉为载体固定化SOD效果好,经改进的邻苯三酚法可用于固定化SOD的活性测定。 相似文献
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RICHARD S. LAMAR 《Journal of the American Ceramic Society》1954,37(8):386-390
The turbidimetric method of determining particle-size distribution, developed by Musgrave and Harner, has been modified and adapted for use with tales, clays, and similar nonmetallic minerals and ceramic raw materials. Results obtained by this method have been found to be reproducible to within ±2%, and check with those obtained by the Andreasen pipette method within the same limits of accuracy. The turbidimetric method is useful for the direct determination of sizes from 60 to 0.25μ, equivalent spherical diameter. The entire procedure for a complete particle-size-distribution analysis usually requires less than 1 hour as compared with several days for the analysis of similar materials by the pipette method. 相似文献
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与常规水网络相比,具有中间水道的水网络更有利于运行和控制。浓度势是作者最近提出的解决多杂质用水网络设计的新概念。在浓度势概念基础上提出了一种具有中间水道的多杂质用水网络设计新方法。该方法采用浓度势方法设计出初始水网络,并在此基础上初步确定各中间水道的结构及水量,然后根据浓度势从小到大的顺序依次由中间水道满足各用水过程,而各级中间水道的最终水量以能满足各级水阱需求来确定。该方法只需简单计算即可完成具有两级中间水道的水网络设计。对文献实例求解结果表明,所得结果与由数学规划法得出的结果接近。 相似文献
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The applicability of NIR for oil and moisture analyses of sunflower seed was determined using a NIR spectrocomputer system.
The method was compared with the wide-line NMR method for oil analysis and with the A.O.C.S. oven method for moisture analysis.
The NIR was calibrated with 120 samples for oil (96 for calibration, 24 for prediction) and 63 samples for moisture (55 for
calibration, 8 for prediction). Twenty-two sunflower seed samples were analyzed for oil and moisture by NIR and by methods
used by industry. The oil contents of the samples by NMR and NIR were not significantly different. The overall mean oil contents
and mean of the standard deviations for the samples were: NMR, 44.2%±0.35% and NIR, 44.34%±0.74%. A significant difference
was found between the moisture values obtained by the oven-drying method and NIR. The average standard deviation for moisture
by NIR was 0.57% compared with 0.07% for the oven-drying method. The variability of the oil content in one of the commercial
seed samples was 1.52% oil as determined by NMR and 2.52% as determined by NIR. The advantages and disadvantages of both methods
are discussed. 相似文献
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目的建立简便、快速、安全的乳酸菌质粒提取方法。方法将文献报道的乳酸菌质粒提取方法和大肠杆菌质粒提取方法相结合,建立乳酸菌质粒提取方法。通过方法比较、溶菌酶浓度优化和酶切分析,验证该方法的可行性。结果用所建立的方法提取的乳酸菌质粒电泳与酶切图谱与文献报道的提取方法相比均无明显差异。溶菌酶最佳浓度为10mg/ml,避免了毒性物质溴化乙锭的应用,减少了溶菌酶的用量和溶液体积。结论所建立的方法可用于乳酸菌质粒的快速提取,为乳酸菌分子生物学研究奠定了基础。 相似文献
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James W. Gentry 《加拿大化工杂志》1970,48(4):451-455
A new method for the numerical solution of a stagewise process is presented. The method consists of total linearization of all the equations in the distillation process, using the method of quasi-linearization. The resulting equations form a block-band matrix which can be readily solved by a method developed by the author. The method used for obtaining convergence is presented. The method has been tested for both binary and multi-component systems. The method has been compared with the Amundson-Pontinen method for a five component mixture. The method gives more rapid convergence. Numerical experiments indicate that the vapor and liquid flow rates are more stringent requirements than the bubble point. 相似文献
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洗涤剂中甲醛的含量测定方法研究 总被引:2,自引:0,他引:2
文章先用水蒸气蒸馏的方式制备样品,后用乙酰丙酮的比色法进行检测洗涤剂中的甲醛含量。该方法有效地排除了比色法检测中的有色洗涤剂对样品成色的干扰及有效地解决了膏状洗涤剂样品难以提取纯净液体甲醛检测样品的问题,经实验证实与GB/T 9985-2000洗洁精甲醛的测定方法测定结果相吻合,为测定洗涤剂和洗涤剂原材料中的甲醛含量提供了一种既简便又准确的途径。 相似文献