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无花果叶中补骨脂素的分离纯化工艺研究 总被引:1,自引:0,他引:1
研究了大孔树脂分离纯化无花果叶中补骨脂素的工艺条件及树脂前处理的方法。以补骨脂素洗脱率和纯度为考察指标,确定DM101型大孔吸附树脂分离纯化补骨脂素的吸附性能和洗脱参数,建立用紫外分光光度法进行大孔树脂前处理的方法。结果表明,DM101型大孔吸附树脂吸附容量以干树脂计为9.76mg·g~(-1),用纯化水和不同浓度的乙醇依次洗脱,以60%乙醇洗脱效果最佳,洗脱率达90.76%,总干燥物中补骨脂素含量达69.28%。大孔吸附树脂对补骨脂素有较好的分离纯化作用,且工艺简单,成本低,易于工业化生产。 相似文献
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以总黄酮的吸附量、回收率及解吸率为考察指标,研究了大孔吸附树脂分离纯化追风伞总黄酮的工艺条件。通过静态吸附实验比较了7种不同类型大孔吸附树脂的吸附特性,确定了D101型大孔吸附树脂用于追风伞总黄酮的纯化富集。通过动态吸附实验,确定了D101型大孔吸附树脂分离纯化追风伞总黄酮的最佳工艺条件为:上样液浓度1.839 mg.mL-1,上样流速为2.0 mL.min-1,洗脱剂为70%乙醇,洗脱剂用量为6 BV。在此条件下,D101型大孔吸附树脂对追风伞总黄酮的动态饱和吸附量为80.05 mg.g-1,纯化后追风伞总黄酮的纯度达到86.2%。D101型大孔吸附树脂可以较好地分离纯化追风伞总黄酮。 相似文献
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乙烯酮(双乙烯酮)是十分重要的化工中间体,其下游产品较多。江苏某化工厂开发生产乙烯酮(双乙烯酮)下游产品三十多个,年生产规模三万多吨,是国内以乙烯酮(双乙烯酮)为中间体生产精细化学品的综合骨干企业。针对乙烯酮(双乙烯酮)下游产品废水特点,该厂结合企业实际,开展了产品优化,结构调整,清洁生产,资源循环利用,节水降耗等工作,从源头削减了污染物的生产。同时投资二千多万元新建预处理装置三套,6000m3/d废水生化处理装置一套,使全厂乙烯酮(双乙烯酮)下游产品的废水得到了有效的治理。 相似文献
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The miscibility of various amorphous polybutadienes with mixed microstructures of 1,4 addition units (cis, 1,4 and trans 1,4) and 1,2 addition units have been investigated. The studies here involved optical transparency, differential scanning calorimetry, and small angle light scattering. It was found that a 90 percent (cis) 1, 4 addition polybutadiene was immiscible with high (91 percent) 1,2 addition polybutadiene. Reduction of the 1,2 content to 71 percent induced an upper critical solution temperature (UCST) with the cis 1,4 polymer. Polybutadienes with 50 percent and 10 percent 1,2 contents were miscible above the crystalline melting temperature of the cis 1,4 polybutadiene. Immiscibility of the 91 percent 1,2 addition polymer was also found with a 10 percent 1,2 polybutadiene. The latter polymer also exhibits an UCST with the 71 percent 1,2 polymer. The results are used to interpret the characteristics of blends of polybutadienes of varying microstructure. 相似文献
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以F类粉煤灰为例,详细介绍了测定粉煤灰中烧失量的步骤、计算数学模型、影响测量不确定度的因素以及各项测量不确定度分量评定,人员、设备、材料、方法、环境都是影响测量不确定的因素。 相似文献
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我厂3号回转窑(Φ4m×60m)生产线在1996年年底由SP窑(产量912t/d)改为NSP窑(产量1320t/d),预分解系统为四级旋风预热器带离线式分解炉 相似文献
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The objective of the study was to explore the effect of the degree of deacetylation (DD) of the chitosan used on the degradation rate and rate constant during ultrasonic degradation. Chitin was extracted from red shrimp process waste. Four different DD chitosans were prepared from chitin by alkali deacetylation. Those chitosans were degraded by ultrasonic radiation to different molecular weights. Changes of the molecular weight were determined by light scattering, and data of molecular weight changes were used to calculate the degradation rate and rate constant. The results were as follows: The molecular weight of chitosans decreased with an increasing ultrasonication time. The curves of the molecular weight versus the ultrasonication time were broken at 1‐h treatment. The degradation rate and rate constant of sonolysis decreased with an increasing ultrasonication time. This may be because the chances of being attacked by the cavitation energy increased with an increasing molecular weight species and may be because smaller molecular weight species have shorter relaxation times and, thus, can alleviate the sonication stress easier. However, the degradation rate and rate constant of sonolysis increased with an increasing DD of the chitosan used. This may be because the flexibilitier molecules of higher DD chitosans are more susceptible to the shear force of elongation flow generated by the cavitation field or due to the bond energy difference of acetamido and β‐1,4‐glucoside linkage or hydrogen bonds. Breakage of the β‐1,4‐glucoside linkage will result in lower molecular weight and an increasing reaction rate and rate constant. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 90: 3526–3531, 2003 相似文献