高效液相色谱法测定人体血液中的氯喹

1　引　　言氯喹 (ｃｈｌｏｒｏｑｕｉｎｅ) ,其化学名称为 4 (4′ 二乙胺基 1′ 甲基丁胺基 ) 7 氯喹啉 ,是一种高效、速效被全世界广泛使用的临床治疗和预防疟疾药物 ,口服后经肠道吸收 ,直接作用于红细胞内期裂殖体 ,在 2 4～ 48ｈ内症状消失 ,但服药后病人的毒副反应较严重。本文拟通过口服单剂量氯喹后不同时期血液中氯喹含量的监测 ,为治疗疟疾新方案提供参考。据文献报道 ,血液中氯喹浓度的测定方法有荧光法 ,酶联免疫法 ,放射免疫法和高效液相色谱法。本文采用一种快速、简便的测定血液中氯喹含量的高效液相色谱分析方法。2　实验…     

水分子通道蛋白的结构与功能

水分子穿越双磷脂生物膜的输运机理是生理学和细胞生物学中一个长期未能解决的重要问题.AQP1水通道蛋白的发现和鉴定使得人们确认出一个新的蛋白质家族--水通道蛋白家族.正是这一蛋白家族的存在,使得水分子可以进行快速的跨膜传输.由晶体学方法解出的哺乳动物AQP1水通道蛋白的原子结构,最终揭示了水通道蛋白只允许水分子快速传输而阻挡其他的小分子和离子(包括质子H+)的筛选输运机理.本文概述了水通道蛋白的发现和其对水分子的筛选传输机理.     

水凝胶基仿生离子通道及其智能离子传输

离子可控传输是维持众多正常生理活动的重要基础,而实现可控离子传输的关键是生命体系中的各类蛋白质离子通道.受此启发,科研工作者开发了一系列仿生智能离子通道,实现了类似生命体中的可控离子传输.其中,基于水凝胶体系的离子通道由于其空间荷电性和三维互通特性,展现出高离子选择性和高离子通量的优点.同时,水凝胶基离子通道的生物相容性、可形变特性及稳定的离子储存特性,使其成为智能离子传输领域的研究热点之一,该类材料已被广泛应用于离子-电子电路、医疗健康、能源转化与存储以及资源与环境等领域.本文主要从水凝胶基智能离子通道的构筑方法出发,阐述了凝胶内部离子传输机制,并对其在各领域的应用进行了总结,最后对目前水凝胶基离子通道存在的问题及未来发展趋势进行了展望.     

水和醇类分子及其混合物在纳米孔道材料中的传输扩散

随着计算机科学技术的飞速发展,理论计算特别是分子动力学模拟技术在研究受限流体的性质时发挥着独特的作用.本文综述了近年来水和醇类分子及其混合物在纳米孔道材料中传输扩散的研究进展,包括单组分水、甲醇和乙醇等在多种纳米孔道材料中的传输扩散,以及甲醇/水和乙醇/水等混合物在碳纳米管和沸石膜中的吸附和分离,讨论了体系温度、分子浓度以及纳米孔道材料结构等因素对水和醇类分子传输扩散过程的影响.     

水汽在涂层中的扩散传输行为和存在形式

利用石英晶体微天平(QCM)为主要手段,研究了水汽在醇酸清漆和聚氨酯清漆涂层中的扩散传输行为.当相对湿度(RH)大于30％时,吸附和脱附动力学都符合Fick第二扩散定律,溶解性遵守Henry定律.计算出了平均扩散系数D.当吸水后的样品重新暴露于干燥空气时,总有一部分水残留于涂层中.傅利叶变换红外光谱仪(FTIR)测定表明吸水前和脱水后涂层分子结构发生了变化.残留水与涂层分子中的羰基C=O形成了氢键.水在涂层中有相当部分可能是以相互置换的链传递方式传输.形成氢键的速度比扩散速度快得多,当RH大于30％时,涂层中水的浓度足以支持其反应,扩散为吸水过程的控制步骤,此时表现为符合Fick第二扩散定律;当RH低于30％时,涂层中水的浓度不足以支持其反应,反应速度降到和扩散速度可相比,此时吸水过程开始偏离Fick第二扩散定律.     

四甲铵阳离子在水/硝基苯界面传输的新极谱法研究

本文采用新极谱法, 包括半积分, 半微分, 1.5次微分及2.5次微分新极谱研究了四甲铵离子在水/硝基苯界面的传输, 从理论上讨论了峰高, 峰电位及峰宽对传输质点浓度, 扫描速率等因系的依赖关系, 用模拟电子线路在实验上对离子在两相界面传输的新极谱法理论进行了验证, 实验与理论接近, 得到了与金属电极/电解质溶液界面的氧化还原类似的结果.     

一锅法合成2，4，6-三氯喹唑啉和6-硝基-2，4-二氯喹唑啉

在五氯化磷的存在下,2-氨基-5-氯苯甲酸(1a)或2-氨基-5-硝基苯甲酸(1b)与尿素缩合,一锅法合成了2,4,6-三氯喹唑啉(2a)或6-硝基-2,4-二氯喹唑啉(2b),其结构经1H NMR和ESI-MS表征.合成2a的最佳反应条件为:1a 2.5 mmol,n(1a):n(PCl5):n(尿素)=1.0:6.0:2.2,回流反应1 h,收率41%.     

含CTAB的开放体系与封闭体系的液膜振荡

本文对水(十六烷基三甲基溴化铵,CTAB)/硝基甲烷(苦味酸)/水(葡萄糖)体系的液膜振荡进行研究.应用电势线性扫描法通过测定界面电压变化研究了开放体系与封闭体系的液膜振荡并进行了对比,对开放体系还研究了不同滴定速度对液膜振荡的影响.根据J.Srividhya和M.S.Gopinathan的数学模型,对开放体系的振荡进...     

紫外/可见光谱在有机光纤研制中的应用

有机光导纤维是近十几年来在新型光功能性高分子材料领域中的一支独秀.相对于玻璃光导纤维,有机光导纤维加工容易、口径大、轻而柔软、抗挠曲、抗冲击、耦合容易,更重要的因素是制作成本低和用途广泛.通常光导纤维是一种带包层的透明圆柱型的细丝.芯子的折射率高于包层并且是不变的,这种纤维称为突变型(SI)光纤.由于SI型光纤的带宽小,不能满足高信息量传输的需要,因而渐变型(GI)有机光纤得以发展.在这种光导纤维中,纤芯的折射率是呈抛物线型分布的,其轴心的折射率最大,折射率由纤维轴心沿径向到包层逐渐变小,在芯/包层界面处折射率无突变,光线在这种光纤的传播路径近似正弦波.沿正弦波处的折射率均小于轴心区的折射率.由于光速是反比于折射率的,因此当光沿着正弦途径传输时,其速度大于光沿着轴心传输的速度.于是,较长的光路被较大的光速所补偿,结果是光在正弦波处的传输时间与在轴心处的传输时间上没有大的区别,而脉冲加宽是正比于传输时间的差值,因此有望在GI型有机光纤中得到较小的脉冲加宽.GI型有机光纤的制备一般可在GI型有机预制棒的基础上通过熔融热拉技术拉制而成.因此,制备GI型有机预制棒及其折射率分布的检测成为关键步骤.折射率分布的测量方法有很多,如近场扫描法、折射近场法、切片干涉法等.本文首次介绍了将紫外/可见吸收光谱应用于预制棒折射率分布的定性测试上,得到了在预制棒芯区沿径向掺杂剂分子溴苯的吸收强度呈抛物线型分布.因测试折射率分布的其他方法较为繁杂以及受仪器的限制,所以利用紫外/可见吸收光谱这一非常普通的仪器来估计折射率分布的情况不失为一种简单易行的方法.     

有机电致发光器件中几种常用组分的荧光光谱研究

利用荧光光谱对电致发光器件(OLED)中几种常用化学组分的荧光猝灭和光诱导电子转移问题进行了研究.发现两种常用的空穴传输材料NPB和TPD与常用电子传输材料AlQ₃在光的帮助下可发生电子转移.根据荧光猝灭的Stern-Volmer作图和用单光子记数法测得的荧光寿命而计算得到的猝灭速度常数和扩散速度常数相对应,明确地表明这里的猝灭具有电子转移特征.并对所得的结果进行了讨论.     

Direct measurement of mass fragmentograms for eluents from a micro-liquid chromatograph using an improved nebulizing interface

An improved vacuum nebulizing interface with a very short counter nozzle was developed for direct coupling of a micro-LC and a quadrupole MS with CI-chamber. With the LC-MS system using the nebulizing interface, it became possible to take mass fragmentograms for various less volatile compounds such as glutamic acid, steroids, aromatic amines and chlorine-containing insecticides.     

Contribution to direct measurement of double-layer potential at the oxide/electrolyte interface

A method for direct measurement of surface-potential changes at the oxide/electrolyte interface is described. It is based upon the semiconductor effect, and, in contrast to the well-known transistor method, it uses an easier-to-prepare field-effect diode.Measurements of the systems SiO₂/electrolyte solution and Al₂O₃/electrolyte solution show, that the Nernst relation is only valid for Al₂O₃, whereas in the case of SiO₂, besides H⁺ and OH^– ions, also electrolyte ions of alkaline chlorides and MgCl₂ are potential-determining.Mitteilung Nr. 814 aus dem Forschungsinstitut für Aufbereitung der AdW der DDR, Freiberg.     

有机太阳能电池给受体材料界面的微纳结构调控

有机太阳能电池因具有成本低、质轻、柔韧性好、可大面积印刷制备等优势,引起了人们极大的关注并成为现阶段有机电子学研究的重要热点之一。有机功能层中电子给体和受体界面特性对电池的功率转换效率影响很大,通过给受体界面的微纳结构化,可扩大给受体的接触面积、缩短给体和受体的距离、增强光吸收,能产生更多激子并促进激子有效分离,从而有效提高器件的电池效率。本文综述了纳米压印、自组装、溶剂挥发以及模板法等调控微纳结构的技术和方法,总结了基于微纳结构构建有机光伏器件的发展现状,并对目前微纳结构化方法和光伏应用中存在问题和研究重点做了简要评述,最后展望了该研究领域下一步的发展方向和应用前景。     

固液界面纳米气泡研究

固液界面纳米气泡是近十年来表面科学的重要发现之一。从利用原子力显微镜(AFM)在固液界面上观察到纳米气泡以来,科学工作者们已经证实了纳米气泡在固液界面上存在。由于其在微机电系统(MEMS)、微生化系统、表面科学、流体动力学等领域潜在的应用价值,各国学者们对纳米气泡的自身性质及影响因素已经开展了多方面的研究。但纳米气泡稳定性(反常的长寿)的原因仍然是未解决的问题之一。本文综述了纳米气泡的形成及影响因素,重点评述了纳米气泡稳定性理论,包括线张力理论、动态平衡理论、杂质理论和克努森气体理论等。同时,介绍了固液界面纳米气泡的应用,并展望了未来研究的重点和方向。     

Thermally stimulated current study of the molecular movements in bone

Thermally Stimulated Current (TSC) has been used for investigating the interface and interphase in a natural composite, bone. Young adult male femoral diaphysis has been studied at different stages of demineralization by EDTA. Analysis of the fine structure of complex TSC spectra has shown that in the early stages of demineralization, dielectric relaxations are due to the hydroxyl reorientations in the mineral apatite structure. After a certain stage of demineralization, the mineral response disappears and organic matrix mobility is observed. A dissociative buffer has been used to identify collagen relaxations. The contribution of the mineral-organic interface/interphase has been isolated.     

固液界面纳米气泡的研究进展

根据经典热力学理论,在水中纳米级的气泡难以长期稳定存在.近年来却有大量的实验结果表明固液界面存在纳米气泡,原子力显微镜也直接观察到了纳米气泡.有关纳米气泡的研究具有巨大的理论和实际意义,它对表面科学、流体动力学、生物科学以及一些应用领域都有深远的影响.纳米气泡会引起流体在界面的滑移,减少流动阻力,并与表面粘附、胶体分散、矿石浮选、废渣处理等方面密切相关.目前关于纳米气泡的研究才刚刚开始,对于它的基本物化性质的了解还不多,但其重要性已经引起相关领域的极大关注.本文综述了从提出纳米气泡存在一直到实验证明的过程、纳米气泡的形成机制和形貌、分布特征等基本性质以及纳米气泡的存在对疏水长程作用和流体滑移的影响,并阐述了生物学中一些与纳米气泡存在有关的问题.     

A liquid-junction/low-flow interface for sensitivity improvement in micelle electrokinetic chromatography–electrospray ionization-mass spectrometry

A liquid-junction/low-flow interface was used to alleviate ion suppression caused by nonvolatile surfactants in micelle electrokinetic chromatography–electrospray ionization-mass spectrometry. Ion suppression due to micelles was alleviated by adjusting operating conditions to keep micelles from entering the ESI source. Two operation modes were investigated. In the first configuration, micelles migrated in the direction opposite to the analytes of interest. A second mode of operation was configured to retain micelles in the liquid-junction between the CE separation column and the ESI interface. In either case, the micelles did not enter the ESI source. To reduce the adverse effect caused by sodium ions, sodium dodecyl sulfate was replaced with the ammonium dodecyl sulfate. Importantly, despite actions taken to alleviate ion suppression, the separation efficiency was preserved as a result of the liquid-junction/low-flow interface. The utility of the described approach for micelle electrokinetic chromatography–electrospray ionization-mass spectrometry was demonstrated by the analysis of sulfonamides at pH 5.5 and pH 7.8, each selected to highlight the two mode of operation.     

2D/2D atomic double-layer WS2/Nb2O5 shell/core nanosheets with ultrafast interfacial charge transfer for boosting photocatalytic H2 evolution

Low-efficiency charge transfer is a critical factor to limit the photocatalytic H₂ evolution activity of semiconductor photocatalysts. The interface design is a promising approach to achieve high charge-transfer efficiency for photocatalysts. Herein, a new 2D/2D atomic double-layer WS₂/Nb₂O₅ shell/core photocatalyst (DLWS/Nb₂O₅) is designed. The atom-resolved HAADF-STEM results unravel the presence of an unusual 2D/2D shell/core interface in DLWS/Nb₂O₅. Taking advantage of the advanced femtosecond-resolved ultrafast TAS spectra, the average lifetime of charge carriers for DLWS/Nb₂O₅ (180.97 ps) is considerably shortened as compared to that of Nb₂O₅ (230.50 ps), strongly indicating that the 2D/2D shell/core interface enables DLWS/Nb₂O₅ to achieve ultrafast charge transfer from Nb₂O₅ to atomic double-layer WS₂, thus yielding a high photocatalytic H₂ evolution rate of 237.6 μmol/h, up to 10.8 times higher than that of pure Nb₂O₅ nanosheet. This study will open a new window for the development of high-efficient photocatalytic systems through the interface design.     

Polymer/surfactant interactions at the air/water interface

The development of neutron reflectometry has transformed the study and understanding of polymer/surfactant mixtures at the air/water interface. A critical assessment of the results from this technique is made by comparing them with the information available from other techniques used to investigate adsorption at this interface. In the last few years, detailed information about the structure and composition of adsorbed layers has been obtained for a wide range of polymer/surfactant mixtures, including neutral polymers and synthetic and naturally occurring polyelectrolytes, with single surfactants or mixtures of surfactants. The use of neutron reflectometry together with surface tensiometry, has allowed the surface behaviour of these mixtures to be related directly to the bulk phase behaviour. We review the broad range of systems that have been studied, from neutral polymers with ionic surfactants to oppositely charged polyelectrolyte/ionic surfactant mixtures. A particular emphasis is placed upon the rich pattern of adsorption behaviour that is seen in oppositely charged polyelectrolyte/surfactant mixtures, much of which had not been reported previously. The strong surface interactions resulting from the electrostatic attractions in these systems have a very pronounced effect on both the surface tension behaviour and on adsorbed layers consisting of polymer/surfactant complexes, often giving rise to significant surface ordering.