一种以毛细作用和蒸发为驱动力的新型微泵的研制

关于微泵的研制起始于20世纪80年代^[1],现已研制开发出很多种类的微泵,如可以用多种驱动力驱动的机械微泵(压电驱动、静电驱动和热气动力驱动等)^[2]和以场感应流微泵为主的非机械微泵(包括电渗泵、磁液态动力泵和电液态动力泵等^[3]).机械微泵的制造工艺复杂,而且液流有脉动性;场感应流微泵的液流无脉动性,流速范围可在每分钟几纳升到每分钟几百微升之间变化,因此被微流控系统广泛采用,但这种微泵需要庞大的驱动器,使用不便.     

聚乙烯醇多孔膜的制备

以醋酸乙烯酯微乳液聚合所得的微乳粒子为占孔物质,通过辅助倒相法制备了聚乙烯醇多孔膜,其中部分孔的尺寸与占孔微乳粒子的大小相近（小于300nm)。利用透射电镜观测微乳粒子的大小和形态并且在扫描电镜下观察PVA多孔膜的孔形态,探讨了通过控制微乳粒子粒径以实现多孔膜孔径调节的可行性。     

聚丁二烯有序多孔膜在热缩型聚乙烯膜上的收缩

采用溶剂散逸自组装制备了聚丁二烯(PB)有序多孔膜。水珠能在冷的高分子溶液表面凝结形成有序的阵列,溶剂蒸发后,高分子材料按照水珠排列的形貌形成了有序多孔膜。两性共聚物的加入能够起到稳定水滴的作用,从而确保多孔膜成为有序的结构。利用聚乙烯可收缩膜将聚丁二烯多孔膜收缩2次,得到长方形、梭形、条形和哑铃形的孔。孔的尺寸从微米级收缩至亚微米级,并对产生各种形状的机理进行了研究。     

一种新型介孔空腔二氧化硅纳米微球的制备与缓释行为

本文用十六烷基三甲基溴化铵(CTAB)作为试剂,通过软模板法合成介孔二氧化硅,利用在合成过程中,由伪莫尔转动所引起的微粒内部的大量缺陷,通过溶剂抽提,形成了具有空腔结构的介孔二氧化硅纳米微球.采用透射电子显微镜(TEM)、X射线粉末衍射仪(XRD)、N2吸附-脱附等手段对产物的形貌和结构进行了详细的表征.并以溴甲酚绿作为目标物,通过改变压强和温度,调节溴甲酚绿进入空心SiO2微球中的不同部位,对所制备的空腔介孔二氧化硅微球进行染料的装载和释放试验.结果显示该微球腔壁具有可渗透性和缓释性,而且在负压蒸发溶剂的情况下可以得到较高的药物负载量和极大地提高缓释性能.     

自制微透析探针性能评价

以自制微透析探针为研究对象,通过体外芍药苷微透析实验,评估灌注液流速、人工细胞外液中药物浓度、回收率测定方法及半透膜性质对自制同轴型微透析探针取样回收率的影响。实验结果表明,自制探针的回收率随灌注液流速升高呈近似指数曲线降低。当灌注流速为8.0μL/min时,回收率表现出浓度依赖性。采用直接透析法或反向透析法所得同一探针回收率存在显著差异。回收率因探针不同而存在差异。探针在体内连续取样6h,半透膜的通量未见衰减。实验室自制探针性能稳定,可用于体内微透析研究。     

聚四氟乙烯微胞孔膜的结构和表征

使用多种方法制备了聚四氟乙烯微胞孔膜，以扫描电子显微镜、化学分析电子能谱及鼓泡测孔径法表征，结果表明，通过等离子体聚合，乙烯－四氟乙烯枝沉淀于基体膜上的方法能可控地获得良好的表征。     

交联结构对肝素/壳聚糖层层组装多层膜内皮细胞相容性的影响

采用1-乙基-(3-二甲基氨基丙基)碳酰二亚胺交联技术对具有抗凝血抗菌作用的肝素/壳聚糖多层膜进行交联, 研究了交联结构对多层膜稳定性和血管内皮细胞亲和性的影响. QCM-D结果显示, 交联可有效地提高多层膜的稳定性, 在模拟人体血液流速(3.0 cm/s)下保持良好的稳定. 体外内皮细胞的研究结果显示, 多层膜的交联可有效地调节肝素/壳聚糖多层膜表面粘弹性, 并显著增加内皮细胞的粘附与生长. 交联的肝素/壳聚糖多层膜有望成为理想的心血管功能界面涂层材料.     

一种用于免疫测定的蛋白质微阵列的制备方法

利用SU-8光刻胶光刻成型技术成功制备了具有进样孔、管道、贮液池和喷孔等结构的微喷阵列芯片,通过调节点样液中DMSO、硼酸盐和PBS溶液的混合比例,降低了点样液的蒸汽压,避免了微量溶液的快速蒸发,稳定了液体在管道中传输速度,提高了蛋白质传输到尼龙膜上的传输效率,避免了管道和喷孔之间的交叉污染,并解决了多次重复利用后残留样品影响等问题。人IgG经过该芯片喷点到尼龙膜形成5×5蛋白质微阵列,与辣根过氧化物酶标记的羊抗人IgG进行抗原抗体反应,25个样品点信号的相对标准偏差能达到4.1%,直径相对标准偏差达到了3.0%。     

相转化法制备超滤和微滤膜的孔结构控制

综述了近期关于超滤和微滤膜孔结构控制的一些研究工作，介绍了相转化法制备聚合物膜过程中可能发生的液－液分相、固－液分相，凝胶化等相转变过程，并依此解析了超滤和微滤膜中常见的结构形态。最后从热力学与动力学两方面探讨了对超滤和微滤膜孔结构进行控制和方法。     

新型光驱动形状记忆有序多孔膜的设计及构筑

长期以来,设计和制备微纳米尺寸的有序多孔结构是材料科学领域的重要研究课题。聚合物有序多孔膜因兼具高度规则的孔结构和聚合物的多功能性,在工程技术和科学研究领域受到广泛关注。有序多孔膜的孔隙大小、形状及可重复使用等性质对其功能化和潜在应用具有重要影响。形状记忆特性是一种独特的环境响应特性。形状记忆材料能够记忆初始形状,并且在形变后能够在外界刺激下回复其初始形状。将形状记忆特性引入到有序多孔膜中,可实现多孔膜孔形状、尺寸的有效调控,并提高薄膜的可重复使用性,但由于多孔膜孔结构难以实现均匀形变,形状记忆有序多孔膜鲜有报道。华东理工大学林绍梁课题组在光驱动形状记忆多孔膜的设计和制备方面取得了一些新进展。     

电子效应对单取代苯定位效应和反应活性的影响

单取代苯的定位效应和反应活性主要受取代基的电子效应控制,列表总结了取代基的电子效应与定位效应和反应活性的关系,分析了烃基电子效应的特殊性,取代基具有-Ⅰ效应的普遍性。除卤素取代基外,探讨了共轭效应的方向对定位效应和反应活性的决定作用。     

Kinetic Studies of Solvent and Pressure Effects on the Thermal Isomerization of Palladium Dithizonate

IntroductionThe photo-and thermo-chromisms of organometallic compounds have been intensivelystudied during thelast1 0 years.Meriwetheretal.[1 ,2 ] examined the chromic behaviorofmet-al-dithizone(phenyldiazenecarbothionic acid2 -phenylhydrazide) complexesin detail.From thekinetic and infrared studies,they showed thatthe central metal of a dithizonate complex de-termined the photochemical stability,the rate of the thermal return reaction,and the colorofthe dithizonate complex.As reported by Mer…     

Optimization of Naringenin Nanoparticles to Improve the Antitussive Effects on Post-Infectious Cough

Naringenin (NRG) is a natural compound with several biological activities; however, its bioavailability is limited owing to poor aqueous solubility. In this study, NRG nanoparticles (NPs) were prepared using the wet media milling method. To obtain NRG NPs with a small particle size and high drug-loading content, the preparation conditions, including stirring time, temperature, stirring speed, and milling media amount, were optimized. The NRG (30 mg) and D-α-tocopherol polyethylene glycol succinate (10 mg) were wet-milled in deionized water (2 mL) with 10 g of zirconia beads via stirring at 50 °C for 2 h at a stirring speed of 300 rpm. As a result, the NRG NPs, with sheet-like morphology and a diameter of approximately 182.2 nm, were successfully prepared. The NRG NPs were stable in the gastrointestinal system and were released effectively after entering the blood circulation. In vivo experiments indicated that the NRG NPs have good antitussive effects. The cough inhibition rate after the administration of the NRG NPs was 66.7%, cough frequency was three times lower, and the potential period was 1.8 times longer than that in the blank model group. In addition, the enzyme biomarkers and histological analysis results revealed that the NRG NPs can effectively regulate the inflammatory and oxidative stress response. In conclusion, the NRG NPs exhibited good oral bioavailability and promoted antitussive and anti-inflammatory effects.     

微波对酶催化反应的影响及其微波效应的研究进展

综述了近年来微波对酶催化反应的影响,包括对酶催化反应速度与转化率或产率的影响,对酶促反应选择性与专一性的影响,对酶结构和活性的影响.总结了研究微波效应的几种技术方法及其在酶催化反应中的应用情况.     

Ab Initio and Density Functional Study on the First Hyperpolarizabilities of Squaric Acid Homologues

The first hyperpolarizabilities of four squaric acid homologues: squaric acid, 1,2-dithiosquaric acid,1,2-diselenosquaric acid and 1,2-ditellurosquaric acid have been calculated using ab initio and DFT methods. The effects of equilibrium geometries, basis set and electron correlation on the first hyperpolarizabilties of these molecules were investigated. The frequency dispersion effect and solvent effect, which are essential to get reliable outputs in comparison to the experimental results, have also been explored. On the basis of these investigations, it is worthy to point out that the heavy atom effect takes effect for these squaric acid homologues.     

Heavy Atom Effect on the First Hyperpolarizabilities of Squaric Acid Homologues Studied by Ab Initio and DFT Methods

1 INTRODUCTION In the past decades, there have been great efforts to research on the molecules nonlinear opti- cal (NLO) properties in which theoretical calcu- lation[1～3] became a powerful tool because it not only explains the micro-mechanism of the mo…     

从13C化学位移分析取代基的诱导效应、共轭效应和亲电取代反应活性间的关系

以单取代苯为模型,建立并论证了取代基诱导效应参数RI、共轭效应参数RC及诱导和共轭共同作用效应参数R,RI=128.5-δ1,RC=642.5-∑6n=2δn,R=771-∑6n=1δn,δn(n=1～6)是单取代苯苯环上6个碳原子Cn(n=1～6)的化学位移,δ1是取代位C1的化学位移,128.5为苯的13C化学位移。当参数R>0时,取代基对苯环有给电子效应。一般而言,RI<0、RC>0、R>0时,取代基是典型的使苯环活化的邻对位定位基;RI<0、RC<0、R<0时,取代基是使苯环钝化的间位定位基;其余情况参考δn的具体数值判定取代基的作用。能与苯环形成最佳共轭的基团,其与苯环直接相连的是与碳原子同周期的B、C、N、O、F。     

磁场对NaCl溶液电解反应的影响

超导电磁船利用固定在船体上的超导磁铁在海水中形成强磁场,并在与此磁场相垂直的方向上通直流电电解海水。由于电磁相互作用,产生洛伦兹力,利用其反作用力,推动船前进。磁场对电解反应的影响,不仅与超导电磁船相关,而且是电化学领域中的一个基础研究课题。作者等在5T磁场下电解NaCl溶液时,观察到加磁场后Cl_2的发生量有减少的     

Effects of geminal disubstitution on C-H and N-H bond dissociation energies

Composite ab initio methods including G3, CBS-Q, and G3B3 were used to calculate the C-H and N-H bond dissociation energies (BDEs) of a variety of disubstituted methane and ammonia molecules. The calculated BDEs were in excellent agreement with the available experimental data. Using these reliable BDEs we studied the effects of geminal disubstitution on C-H and N-H BDEs. It was found that the effects of the two substituents were not additive. Detailed separation of the substituent effects on BDEs to those associated with the parent molecules and those associated with the radicals was then performed using appropriate isodesmic reactions. It was found the geminal substitution effects on the stabilities of methanes, methyl radicals, amines, and amine radicals were all governed by five basic types of energetic effects, namely, hyperconjugation effect (stabilizing), electrostatic attraction (stabilizing) or repulsion (destabilizing), conjugation saturation effect (destabilizing), captodative effect (stabilizing), and steric effect (destabilizing). The conformations of the species played an essential role in determining whether a particular energetic effect could take place. Because the carbon-centered and nitrogen-centered species often had quite different conformational preferences, the geminal substitution effects on these two classes of species were quite dissimilar to each other.     

常见金属离子对漆酶酶活的影响

检测了14种不同的金属离子对两种漆酶(laccaseA和laccaseB,简称LacA和LacB)活性的影响.结果表明:Al3+,Fe3+,Ag+,Hg2+对两种漆酶的活性都有抑制作用,其中Fe3+,Ag+的抑制作用最强,酶活完全损失;Mg2+,Cu2+对两种漆酶的活性有激活作用.