共查询到20条相似文献,搜索用时 140 毫秒
1.
2.
3.
银杏叶黄酮类化合物提取方法的研究 总被引:4,自引:0,他引:4
对纤维素酶预处理和甲基化β-环糊精溶液相结合提取银杏叶总黄酮的工艺进行了探讨,考察了料液比、酶浓度、温度、时间及pH值对酶解效果的影响,以及M-β-环糊精浓度、温度和时间对浸提效果的影响。得到最佳酶解预处理条件为:经料液比(银杏叶质量与纤维素酶溶液体积之比)1/60、酶质量浓度0.2mg/mL、酶解温度40℃、酶解介质pH=6.5、酶解时间150min处理后,在M—β-环糊精质量分数2.0%、温度60℃条件下浸提180min,总黄酮得率可达2.68%。该工艺为银杏叶黄酮类化合物提取提供了新途径,同时避免了有机溶剂的使用,便于纯化,值得推广。 相似文献
4.
5.
制备了复配生物酶废纸脱墨剂,得到了脱墨剂中纤维素酶与脂肪酶的合适配比(3:2).通过实验,考察了脱墨剂用量,纸浆浓度,溶液pH值,脱墨温度,脱墨时间等工艺条件对脱墨效果的影响.实验结果表明,最佳的生物酶用量为0.3%(对绝干废纸),SDBS用量为1.0%(对绝干废纸),碎浆浓度为10%,pH值为6.0,熟化时间30mi... 相似文献
6.
7.
针对××井埋藏浅,温度低(23-25℃),破胶困难的问题,室内评价了BAT生物酶破胶剂在20℃、30℃条件下的破胶性能。结果表明:加入单独BAT生物酶在4h内均不能实现有效破胶;20℃时0.003%BAT生物酶+0.03%APS复配破胶效果最好,30℃时0.003%BAT生物酶+0.01%APS复配破胶效果最好,4小时内均可实现彻底破胶。现场应用表明:BAT生物酶+APS复配破胶技术在××井中可以实现分段破胶,但由于地层温度恢复慢,破胶液粘度下降也较慢,因此低温条件下BAT生物酶破胶剂及复合破胶剂加量需进一步优化研究。 相似文献
8.
9.
10.
全生物酶法杜仲胶提取获重要突破 总被引:1,自引:0,他引:1
贵州省发酵工程与生物制药重点实验室副主任、贵州大学教授张学俊带领研究团队将生物酶解化学与工程学相结合,近日在河南恒瑞源实业公司进行的杜仲树皮批量试验中实现了全生物酶酶解杜仲胶提取,获得的杜仲胶纯度达到92%以上,达到了可作为一般工业原料使用的品级。该研究结果表明,不用化学手段,直接采用全生物酶进行杜仲胶的生产是可以实现的。 相似文献
11.
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
12.
13.
14.
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
15.
16.
17.
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
18.
Conclusions It is significant that the purification on a single passage of viscose through porous ceramic corresponds to the result of a two-stage filtration of it in industrial filter-presses with standard fillings.Kiev Combine. Kiev Technological Institute of Light Industry. Translated from Khimicheskie Volokna, No. 3, pp. 20–22, May–June, 1969. 相似文献
19.
20.
A refined nonlinear value of the main parameter of a material, i.e., the elongation modulus versus the instant temperature value, was suggested for introduction into the computational algorithm of tempering stresses. 相似文献