共查询到20条相似文献,搜索用时 0 毫秒
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以假丝酵母脂肪酶(Candida sp.lipase)为研究对象,开发了一种新型层状交联酶聚集体。用蛋白或氨基酸对纳米氧化锌粒子进行修饰,继以交联剂交联后作为核芯,酶分子再交联在纳米核表面形成层状结构。实验结果表明牛血清白蛋白(BSA)是纳米氧化锌适宜的修饰剂。并且对纳米芯层状交联酶聚集体(BSA-N-LCLEAs)其他制备条件进行了优化,优化后BSA-N-LCLEAs制备条件为:沉淀剂硫酸铵饱和度为58%,交联剂戊二醛浓度为3.5%,交联温度和时间分别为0℃和2 h。BSA-N-LCLEAs酶活收率较传统CLEAs提高了196.5%。扫描电镜表征表明BSA-N-LCLEAs较传统CLEAs孔道大幅增加。纳米芯层状CLEAs的pH稳定性和热稳定性也都比传统CLEAs有所提高,并将该固定化酶用于催化维生素E琥珀酸酯的合成,反应五批次后反应产率还能达90%左右,说明该新型交联酶聚集体具有良好的催化活性和操作稳定性。 相似文献
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Gizem Ölçücü Dr. Ulrich Krauss Prof. Dr. Karl-Erich Jaeger Prof. Dr. Jörg Pietruszka 《化学,工程师,技术》2023,95(4):531-542
For the development of efficient and green industrial processes, the combination of biocatalysis and flow chemistry holds great promises. Flow chemical utilization of biocatalysts, essentially made possible by the immobilization (or retention) of enzymes in flow reactors, has attracted increased academic attention during recent years. In the present review we present an overview of immobilization strategies suitable for flow chemistry, particularly focusing on recently developed carrier-free immobilization methods, highlighting advances in the field and presenting future trends. 相似文献
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金属有机框架(MOFs)具有比表面积大、设计性强和生物相容性好等优良特性,可以作为固定化酶的理想载体,从而提高游离酶的稳定性和催化性能,许多酶/MOFs复合材料也显示出比游离酶更好的催化性能。因此,酶/MOFs复合材料已应用于生物传感、检测、催化等领域,已成为传统催化剂的环保替代品。综述了酶在MOFs上的3种固定化方法(表面固定、孔封装和原位包埋法),重点介绍了4种影响酶/MOFs复合材料催化性能的因素及调控方法,对酶/MOFs复合材料在催化方面的应用也进行了总结,并对酶固定化的未来进行了展望。 相似文献
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Niru Ye Xiaoxue Kou Prof. Jun Shen Dr. Siming Huang Dr. Guosheng Chen Prof. Gangfeng Ouyang 《Chembiochem : a European journal of chemical biology》2020,21(18):2585-2590
Metal-organic frameworks (MOFs) with attractive properties such as high surface area, tunable porosity, designable functionality and excellent stability, have aroused great interest from researchers as the matrices for enzyme immobilization. Recently, several efficient strategies including surface immobilization, post-synthetic infiltration and in situ encapsulation have been explored. MOF-immobilized enzymes, named enzymes@MOFs, show remarkably enhanced stability and recyclability, accelerating cell-free biocatalysis in diverse applications. This concept will impart the typical strategies for enzyme immobilization with MOFs, and their potential applications. 相似文献
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J Jegan Roy T Emilia Abraham 《Journal of chemical technology and biotechnology (Oxford, Oxfordshire : 1986)》2006,81(11):1836-1839
Cross‐linked enzyme crystals (CLEC) of laccase were prepared by crystallizing laccase with 75% (NH4)2SO4 and cross‐linking using 1.5% glutaraldehyde. The cross‐linked enzyme crystals were further coated with 1 mmol L?1 β‐cyclodextrin by lyophilization. The lyophilized enzyme crystals were used as such for the biotransformation of pyrogallol to purpurogallin in a packed‐bed reactor. The maximum conversion (76.28%) was obtained with 3 mmol L?1 pyrogallol at a residence time of 7.1 s. The maximum productivity (269.03 g L?1 h?1) of purpurogallin was obtained with 5 mmol L?1 pyrogallol at a residence time of 3.5 s. The productivity was found to be 261.14 g L?1 h?1 and 251.1 g L?1 h?1 when concentrations of 3 mmol L?1 and 7 mmol L?1 respectively were used. The reaction rate of purpurogallin synthesis was maximum (2241.94 mg purpurogallin mg?1 CLEC h?1) at a residence time of 3.5 s, when 5 mmol L?1 pyrogallol was used as the substrate. The catalyst to product ratio calculated for the present biotransformation was 1:2241. The CLEC laccase had very high stability in reuse and even after 650 h of continuous use, the enzyme did not lose its activity. Copyright © 2006 Society of Chemical Industry 相似文献
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Winston Duo Wu Kamlesh C. Patel Samuel Rogers Xiao Dong Chen 《Drying Technology》2007,25(12):1907-1916
Spray drying is a widely used unit operation for manufacturing powders of different characteristics. Many technological improvements have been made in the last few decades, and a great amount of research work is still being conducted. Recently, the hybrid spray-drying technique was reported, which combines the ink-jet technology with spray drying in order to produce particles of uniform characteristics.[1-41, 2, 3, 4] The monodisperse droplet generators (MDGs) have certain features that make them attractive for use as atomizers in spray-drying operations. In this article, a comprehensive introduction to a variety of monodisperse droplet generators is provided. The advantages and limitations of these generators are discussed. The fundamental equations for predictions of the average droplet size are summarized. The discussion given in this study is aimed at the development of a hybrid technology that marries a suitable MDG with the existing spray-dryer technique (yet with some modifications) to manufacture the product with uniform characteristics containing micro- to nanosized particles. 相似文献
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Spray drying is a widely used unit operation for manufacturing powders of different characteristics. Many technological improvements have been made in the last few decades, and a great amount of research work is still being conducted. Recently, the hybrid spray-drying technique was reported, which combines the ink-jet technology with spray drying in order to produce particles of uniform characteristics.[ 1-4 ] The monodisperse droplet generators (MDGs) have certain features that make them attractive for use as atomizers in spray-drying operations. In this article, a comprehensive introduction to a variety of monodisperse droplet generators is provided. The advantages and limitations of these generators are discussed. The fundamental equations for predictions of the average droplet size are summarized. The discussion given in this study is aimed at the development of a hybrid technology that marries a suitable MDG with the existing spray-dryer technique (yet with some modifications) to manufacture the product with uniform characteristics containing micro- to nanosized particles. 相似文献
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本文评述了一种新的清洗工艺——喷淋式化学清洗法的研制、应用,且在实践中取得了很好的效果.使大容积的储槽(罐)的化学清洗工作不仅可行,且费用低,省时,省力.不失为一种集合理性、经济性、实用性很高的清洗工艺. 相似文献
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介绍了一种应用在家用电器喷涂中的内喷涂的高效装置———三维自动跟踪喷涂装置,分析其喷涂的程序和路径,计算其在内喷涂时的有效工作时间足以喷涂好工件的内腔。 相似文献
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喷雾降温技术在造气循环水系统中的应用 总被引:1,自引:0,他引:1
介绍了无填料喷雾塔技术对造气循环水系统凉水塔改造的实际应用。从增加恒压盒和过滤器、采用管道变径保压技术、轴流风机的选择和安装等方面阐述了改造安装过程中需特别注意的几项技术措施,对改造前后降温效果进行了对比,结果表明,循环水温由34.8℃降至28.8℃。 相似文献
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Disperse Amphiphilic Submicron Particles as Non‐Covalent Supports for Cationic Homogeneous Catalysts
Rafaël Sablong JarlIvar vanderVlugt Ralf Thomann Stefan Mecking Dieter Vogt 《Advanced Synthesis \u0026amp; Catalysis》2005,347(5):633-636
A simple method for the effective immobilization of homogeneous catalysts on polystyrene colloids via non‐covalent binding is demonstrated. Stable latices with sufficiently high loading of accessible borate anions are prepared via emulsion polymerization. Incorporation of cationic rhodium complexes, supported via their borate counter‐anion is efficient, and these supported homogeneous catalysts maintain constant catalytic activity for CC hydrogenation during several recycles, with very low metal leaching. 相似文献