纳米气泡制备和检测方法研究进展

纳米气泡凭借独特的物理化学性质和生理活性引起了国内外的广泛关注,其在废水处理、土壤和地下水修复、矿物浮选、动植物生长以及生物医学等领域具有良好的发展空间和应用前景.近年来,随着各类技术的不断进步,人们对纳米气泡的研究工作取得了一系列成果,尤其是在纳米气泡的形成机制和测定方法方面.文中概述了目前国内外纳米气泡常用的制备方...     

界面纳米气泡研究历史和展望

界面科学研究因其在工业、农业、环境和催化等领域的重要性一直是国内外科学工作者非常关注的领域.固液界面纳米气泡的发现和研究是近20年来科学界的一匹"黑马",它的存在颠覆了人们的认知,以超乎常人想象的效果在水处理、农业、矿物浮选、界面输运和清洗等领域表现出色,成为国内外相关领域的研究热点.该综述对界面纳米气泡的研究历史、产...     

微纳米气泡及其在环境工程领域的应用

微纳米气泡因其区别于传统气泡的突出特性,近年来被广泛应用到环境工程领域,并表现出显著的技术优势与广阔的应用前景.文章简要介绍了微米气泡和纳米气泡的特性、制备方法、表征手段及其在环境工程领域的应用现状,并针对性地指出了当前各方面存在的问题,给出了解决对策和方向.最后,对微纳米气泡及其在环境工程领域应用的发展方向和应用前景...     

纳米气泡的特性及其在水处理中的应用

纳米气泡因稳定性强、界面Zeta电位高、传质效率高以及可产生羟基自由基,广泛应用于去除水中有机物、给水消毒、地表水净化、地下水修复等水处理技术中。文中系统概述了纳米气泡的特性及在水处理中的应用,并提出研发简单高效的纳米气泡发生装置、与其他技术连用、建立水质-纳米气泡发生装置及气泡动力学模型等问题。     

微纳米气泡复合高级氧化技术降解污染物研究进展

介绍了难降解有机废水在水处理方面的特点,以及高级氧化技术降解有机污染物的机理,叙述了微纳米气泡的定义、特性和常见的产生方式,分析了各种常见的微纳米气泡复合高级氧化技术的应用,重点介绍了臭氧微纳米气泡技术和光催化微纳米气泡技术,总结了微纳米气泡复合高级氧化技术各种常见的实验装置及其应用.得出微纳米气泡作为一种新型的高级氧...     

微纳米气泡控制膜污染研究进展

膜污染是阻碍膜分离技术大规模推广应用的主要问题之一,膜污染控制技术一直都是膜科学领域的研究热点.其中,基于气液两相流的膜污染防控技术已经得到了诸多研究和广泛应用.微纳米气泡因其不同于普通大气泡的独特物理化学性质,近年来在各个领域被广泛关注,而微纳米气泡控制膜污染的研究也日益活跃.文中综述了气液两相流控制膜污染技术的相关...     

微纳米气泡形成羟基自由基的研究进展

从微纳米气泡溶液中是否可以产生·OH、·OH的鉴别方法、·OH的生成机理以及强化·OH的生成等几个方面论述了微纳米气泡溶液中生成·OH的研究进展.电子自旋共振技术和荧光分光光度法作为检测·OH的2种技术,均存在一定的误导性,对于荧光分光光度法,最重要的就是排除H2 O2的干扰.此外,目前要获得含有高浓度·OH的微纳米气...     

臭氧微纳米气泡技术在水处理中的应用进展

臭氧是水处理领域常用的氧化剂之一,在水处理领域应用广泛。微纳米气泡技术由于其不同于普通气泡的特性,在水处理领域显现出良好的应用前景。文中阐述了微纳米气泡特性及优势,总结了臭氧在水处理应用中存在的主要问题,并综述了臭氧微纳米气泡技术在水处理中的应用现状和前景。     

微纳米气泡技术在渔业水产行业的研究进展及应用综述

微纳米气泡技术是当前国内外的前沿科技,也是研究的热点。该文详细介绍了微纳米气泡在悬浮物的吸附去除、有机物的强化分解及促进生物活性等方面的最新研究进展与应用现状。综述了微纳米气泡发生装置的各种原理和结构,并对其应用进展进行了分析和探讨,特别介绍了在渔业水产相关领域的研究应用情况。指出了微纳米气泡技术目前面临的主要问题及对渔业研究领域的启示,以期为微纳米气泡在水产养殖、捕捞、加工等领域的理论研究和技术应用提供参考。     

微纳米气泡的特性表征研究

为进一步探究微纳米气泡发生系统的性能。基于喷射法原理,研究文丘里管内径、气泡发生器孔径和级数等因素对微纳米气泡粒径分布的影响。经实验测试,结果表明：当文丘里管内径由2.7 mm增至2.9 mm,气泡粒径随内径增加呈先减小后增大趋势,即气泡的平均粒径由10.88μm先减小至3.069μm,后增大至7.997μm;当气泡发生器孔径从0.7 mm增加至0.9 mm,气泡粒径随孔径增加呈递减趋势,即气泡的平均粒径由4.106μm减至2.954μm;当级数由1增至3级时,气泡粒径随级数增加基本保持一致。     

氟喹诺酮类原料药前景与竞争分析

世界抗感染药物市场重心正由头孢菌素类药物向氟喹诺酮类药物转移 ,氟喹诺酮类药物成为抗生素药物中发展最快的领域。我国氟喹诺酮类原料药的市场前景不仅取决于国际的竞争 ,还在于是否能够把握“重磅炸弹”专利药物过期的契机与同类药物的更迭。氟喹诺酮类原料药企业需要结合自身产品战略 ,分析竞争形势 ,合理调整产品线 ,以获得更强竞争优势。     

Magnetic nanoparticles: preparation, physical properties, and applications in biomedicine

ABSTRACT: Finally, we have addressed some relevant findings on the importance of having well-defined synthetic strategies developed for the generation of MNPs, with a focus on particle formation mechanism and recent modifications made on the preparation of monodisperse samples of relatively large quantities not only with similar physical features, but also with similar crystallochemical characteristics. Then, different methodologies for the functionalization of the prepared MNPs together with the characterization techniques are explained. Theorical views on the magnetism of nanoparticles are considered.     

无皂乳液聚合的研究及应用

无皂乳液聚合由于不含或含有少量的乳化剂，消除了传统乳液聚合中乳化剂对环境的污染，增强了乳液涂膜的耐水性，并可制备表面清洁、粒径均匀分散的高分子微球，在许多领域已得到了广泛的应用，并具有广阔的开发前景。介绍了无皂乳液聚合的反应机理、影响稳定性的因素及制备和应用。     

八甲基环四硅氧烷/氨基取代有机硅单体的本体阴离子共聚动力学

通过实验分析了八甲基环四硅氧烷(D4)／N—β—氨乙基-γ-氨丙基甲基二甲氧基硅烷(APAEDMS)的本体共聚机理，并结合普适的阴离子聚合机制建立了D4／APAEDMS本体共聚速率模型。通过因素(温度、催化剂浓度及原料单体配比)实验考核并完善了所建立的速率模型。研究表明，D4／APAEDMS的本体共聚具有阴离子聚合特点，也含有部分逐步聚合行为，在APAEDMS/D4质量比小的情况下，可以用普适的阴离子聚合方程进行模型化。     

新型无皂乳液聚合的研究与进展

介绍了无皂乳液聚合的反应机理以及影响无皂乳液稳定性的因素和增强稳定性的方法,着重介绍了当今无皂乳液聚合的最新研究动态、应用。     

Microbial polysaccharide‐based membranes: Current and future applications

Microbial polysaccharides are characterized by high molecular structure variability which translates into a wide range of different properties offering interesting opportunities for application in many different areas, including membrane‐based products and processes. Due to their new or improved properties, microbial polysaccharides can replace plant, algae, and animal products, either in their traditional or in new applications. The main constraint to their wider use is the production costs that are still higher than that of other natural and synthetic polymers. The current applications of microbial polysaccharide membranes in medical, food, and industrial processes are outlined. The limitations still faced by these membranes and the requirements for obtaining innovative products and processes are also addressed. © 2013 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2014 , 131, 40047.     

Preparation and characterization of lovastatin polymeric microparticles by coacervation‐phase separation method for dissolution enhancement

Dissolution rate of lovastatin is slow, only 30% of the oral dose is absorbed, and it undergoes extensive first‐pass extraction resulting in low and variable bioavailability. The objective of this research was to enhance the dissolution rate through preparing polymeric microparticles. Coacervation‐phase separation method through the addition of a non‐solvent was used to prepare polymeric microparticles. The method was optimized through studying effects of the type of solvent, the type of polymer, drug : polymer ratio and concentration of surfactant on particle size, particle size distribution, and in‐vitro drug release. Optimized polymeric microparticles and unprocessed drug were characterized using different techniques (SEM, FTIR, DSC, and PXRD) and their flow properties were evaluated. The optimum microparticles were prepared using ethanol as a solvent, Eudragit^® L 100 as a polymer in a drug:polymer ratio of 1:2 and SDS in a concentration of 0.25%. Characterization techniques indicated a change from the crystalline form to an amorphous form that was molecularly dispersed into the polymer. Flow properties of these microparticles were improved as compared to unprocessed drug. Drug release was enhanced 4‐ to 5‐folds probably due to precipitation of the drug in an amorphous form; wetting enhancement; size reduction and stabilization by polymers and surfactants. In conclusion the selection of proper process parameters enhanced drug release 5 folds. The use of DMSO as a solvent and the preparation of physical mixtures in this research provided a means for controlled or prolonged release. © 2015 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2016 , 133, 43277.     

Pebax membrane for CO2/CH4 separation: Effects of various solvents on morphology and performance

In this study, the effects of different solvents on the morphology and permeation of poly(ether‐block‐amide) (Pebax‐1657) membranes were investigated. Pebax membranes were fabricated via a solution casting method with five different solvents, that is, N,N‐dimethyl formamide (DMF), N,N‐dimethyl acetamide (DMAc), N‐methyl‐2‐pyrrolidone (NMP), formic acid, and a mixture of ethanol (EtOH) with water (H₂O). Cross‐sectional scanning electron microscopy analysis of the membranes was performed to investigate the morphology of the prepared membranes. X‐ray diffraction and Fourier transform infrared analysis were also carried out to characterize the membranes. The interactions of the polymer and various solvents were evaluated with Hansen solubility parameters. Permeation experiments for CO₂ and CH₄ gases were performed to study the effects of the solvents on the permeation properties of the membranes. The solvent properties, such as the molar volume, boiling point, and solubility parameters, were investigated as were the membranes characteristics, such as the crystallinity, d‐spacing, and fractional free volume. The results obtained from the experiments show that the CO₂ permeability for the membranes prepared with different solvents followed this order: NMP > DMF > Formic acid > DMAc > H₂O/EtOH mixture. With increasing molar volume, the gas permeability increased for all of the membranes, except for DMAc, which showed a lower permeability because of its highly crystalline structure. DMF showed a higher CO₂/CH₄ ideal selectivity compared to the other membranes and, consequently, could be introduced as the best solvent from all aspects for the Pebax‐1657 membrane. © 2016 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2017 , 134, 44531.