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大孔吸附树脂对葡萄籽原花青素的吸附特性 总被引:3,自引:1,他引:3
从9种大孔吸附树脂中筛选出AB-8树脂对原花青素有较好的吸附和解吸性能。研究了原花青素在AB-8树脂上的吸附特性。静态吸附表明,吸附略有放热,平衡吸附时间为2 h,吸附行为更符合Langmuir等温式,用体积分数为50%的乙醇时解吸效果最好。当流速为1.5 BV/h时,动态泄漏吸附量比静态吸附量低15%,5BV可达到完全洗脱的目的,其原花青素的质量分数可达85.8%。 相似文献
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大孔树脂吸附纯化葡萄籽原花青素的研究 总被引:1,自引:0,他引:1
采用大孔树脂对葡萄籽原花青素进行吸附纯化,以吸附率和解吸率及纯化效果为指标,比较了7种大孔树脂对原花青素的吸附解吸性能。研究了上样量、洗脱剂浓度、上样流速、洗脱剂用量对原花青素纯化效果的影响。结果表明,AB-8大孔树脂对葡萄籽中原花青素的吸附效果最好,树脂体积为20 mL,上样量为80 mL,上样流速为40 mL/h,用40%的乙醇洗脱,洗脱剂用量为100 mL,洗脱流速为80 mL/h时的纯化效果最好,该条件下原花青素洗脱率为94.37%,所得溶质纯度可达89.63%。 相似文献
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《广东化工》2021,48(13)
本研究通过静态吸附-解析试验研究了13种不同类型大孔树脂对樱桃李果皮来源花青素的纯化性能,筛选获得最佳纯化效果的大孔树脂类型以及最佳纯化条件。以静态吸附树脂类型、吸附率和解析率为参考,通过动态吸附-解析试验考察得出最佳樱桃李花青素的柱层析纯化条件:采用DA201-C型大孔树脂制备Φ3 cm×30 cm层析柱(BV=200 cm~3),以0.9 BV/h的速度将浓度为2.5 mg/mL的樱桃李果皮粗提液上柱,最大上样量为0.5 BV,解析液选择45%浓度的乙醇,以0.6 BV/h的速度用洗脱液将吸附的花青素进行洗脱,洗脱量为0.5 BV(100 mL)。经大孔树脂纯化后的樱桃李花青素纯度由26.41%提升至59.36%。通过DPPH自由基清除试验,ABTS自由基清除试验和酪氨酸酶活性抑制试验考察了纯化前后花青素的抗氧化活性和美白活性,经大孔树脂纯化后的花青素在美白、抗衰老等护肤功效活性方面有显著提升。 相似文献
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研究通过静态吸附/解吸实验对大孔吸附树脂进行筛选,优选AB-8大孔吸附树脂作为层析柱填料,并对其进行喜树碱纯化工艺研究;研究表明AB-8树脂对喜树碱的静态吸附率为95.31%;体积分数95%的乙醇静态解吸率为92.4%;最佳吸附条件为:上样液质量浓度为0.175mg/mL,上样液不调pH值,吸附流速为2BV/h,平衡吸附5h;最佳洗脱条件:体积分数95%乙醇,洗脱流速1BV/h,洗脱体积为8BV。在该工艺条件下,洗脱物中喜树碱质量分数为7.43%,洗脱率为83.1%。 相似文献
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Dinesh Singh J. K. Gehlawat Musti S. Rao 《Journal of chemical technology and biotechnology (Oxford, Oxfordshire : 1986)》1990,47(2):127-136
Oslefins and diolefins are important intermediates in the petrochemical industry and the future promises a further substantial increase in demand. While several catalysts have been formulated in the past for the abstraction of hydrogen from butenes and propylene, these catalysts are inefficient in the abstraction of first hydrogen from butane. Bismuth molybdates (β and γ-phases) containing iron oxide and supported on alumina are used as catalysts in the present investigation on the oxidative dehydrogenation of n-butane. Effects of catalyst content, temperature and oxygen: n-butane ratio on conversion and selectivity to butadiene and (C4H8 + C4H6) are studied in the following ranges of experimental conditions: β-bismuth molybdate/100 mol support I(K), 3–9; γ-bismuth molybdate/100 mol support I(K), 5-20; temperature, 400–500°C; O2: butane ratio, 0.6:1.7. 相似文献
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A viscometer used to measure the viscosity of 10 μl of a liquid, must be miniaturized down, and the liquid velocity gradient in the channel used to determine the viscosity coefficient. Two major factors that affect the liquid velocity are the mechanical forces exerted by the mechanical motors and electromagnetic forces. In this study, electrowetting on dielectric (EWOD) is adopted to drive liquids. Variously sized electrodes on a chip, and two shapes of channel are employed to measure the velocity gradient to determine the viscosity coefficient. The device is fabricated by microelectromechanical system (MEMS) technology. The dielectric layer used in EWOD has a high dielectric constant, BST (Ba0.7Sr0.3TiO3), to reduce the required applied voltage; its surface is coated with hydrophobic polymer, polytetrafluoro-ethylene (PTFE, Teflon® AF DuPont). Experimental results demonstrate that liquids can be pulled at 660 μm/s in linear channels by applying a voltage of 15 V. 相似文献
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考登钢作为一种高耐候结构钢,广泛应用于各个领域。在火力发电方面,考登钢主要应用在工作环境比较恶劣的烟气加热器和空气预热器中。考登钢表面涂搪的目的就是进一步提高其耐腐蚀性能,延长使用寿命。为了提高考登钢元件的使用寿命,对考登钢表面涂搪瓷的可行性、密着性能、瓷釉、工艺控制、质量保证等方面进行了研究。 相似文献
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In reexamining medium effects on photochemical reactions, we have emphasized those on unequilibrated excited species such as the Franck-Condon species. Despite recent advances in femtochemistry, such a discussion in molecular photochemistry is uncommon, and the problem remains challenging on account of the extremely short-lived excited species. However, in such cases, a small perturbation resulting from, for example, weak guest-host interactions could turn into a determining factor in dictating the course of a photochemical channel of deactivation. Examples of medium-directed diabatic processes have been examined with this idea in mind. A modified view on rhodopsin photoisomerization is presented along with the consideration that confinement does not necessarily lead to inhibition of reactions of the trapped substrate. 相似文献
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研究了温度和pH值对漆酶酶活以及漆酶处理纤维压制纤维板性能的影响。结果表明,pH较低、温度较高时漆酶酶活较高,压制的纤维板强度性能较好。但温度太高(60~80℃),延长加热时间,漆酶稳定性变差,酶活明显降低,压制纤维板的强度下降。 相似文献
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采用密度泛函理论(DFT)考察了丙烷在Pt(111)表面上脱氢生成丙烯的反应机理。通过在Pt(111)面上预吸附一定数量H原子模拟共吸附H对丙烷脱氢过程的影响。结果表明:H共吸附能降低丙烷及其脱氢产物的吸附能,促进丙烯脱附,有利于提高丙烯的选择性;H共吸附会导致丙烷脱氢能垒变大,降低催化剂的脱氢活性;共吸附的影响随着H覆盖率增加而增大。 相似文献