纳米激光粒度仪在生物药品团聚物测试中的应用

探讨了纳米激光粒度仪测定生物药品团聚物质量浓度的方法。以SALD–7500nano颗粒测试仪为例,介绍其在测量纳米级颗粒物粒度范围方面的应用。通过进一步分析颗粒浓度与光强度成正比的关系获得以质量浓度形式给出的粒度分布数据。通过牛血清蛋白(BSA)团聚物测量的实例,验证了颗粒物质量浓度的测试方法。该方法可用于生物制药领域对团聚物的监控测量以及评价药品药效、安全性能等。     

电感耦合等离子体质谱技术在环境领域的应用

综述电感耦合等离子体质谱技术在环境监测和环境科学研究领域的应用.介绍了电感耦合等离子体质谱技术在环境监测中的分析优势,环境研究领域中稳定同位素比值测定技术及其与色谱、激光烧蚀、流动注射技术联用分析技术应用的进展.     

用激光散射法研究冷冻剂R12水合物的生成动力学

建立了高压混相全透明循环管路装置, 装置中配备有水合物生成器、激光粒度仪和控温系统等, 工作压力可达4 MPa, 用来研究水合物生成动力学行为. 利用激光散射方法, 测定了0.24和0.32 MPa下, 温度为277.1 K 时, 冷冻剂CCl₂F₂, 即R12, 生成水合物的颗粒尺寸和分布, 液体流量范围为300~1400 L/h. 并使用Rosin-Rammler分布分析了所测粒径分布数据. 实验结果表明, 反应初期水相中水合物粒子的直径增加很快, 随着水合物的大量生成, 水相中水合物的浓度不断增加, 水合物颗粒的尺寸逐渐趋于稳定. 在液体流量较大和压力较高的情况下所生成水合物颗粒的浓度较大. 根据物料平衡, 建立了水合物的粒度生长模型, 将水合物生成气消耗量与所生成水合物粒度分布相关联. 基于由粒度生长模型算出的气体消耗量与实测值相近.     

4种激光粒度仪对下蜀土湿法粒度测试的对比研究

使用4种应用较为广泛的激光粒度仪(Mastersizer2000、Bettersize2000、Horiba LA950和LS13320)对粒度差异较小的下蜀土(土塘剖面)进行了测试,从而对比分析不同激光粒度仪对于下蜀土的粒度组成测试差异及其这种差异对研究结果可能产生的影响.结果表明:对粉砂颗粒组分的分析,4种激光粒度分析仪分析结果的差异最小,而对砂和粘土颗粒组分分析的差异最大.就粒度频数曲线、概率累积曲线、粒度组分、C-M图、粒度参数散点图及粒度参数剖面垂向变化等统计参数与统计方式而言,4种仪器的测试结果均有一定的差异,其中,概率累积曲线、粒度参数散点图差异较大.粒度参数的剖面变化差异也较大,影响了对剖面的阶段性划分,这在一定程度上影响了研究结果,造成使用不同仪器,可能会得出不同的结果.     

电照相用近红外敏感有机光导材料

非银照相技术及其材料的发展极为迅速,日益得到广泛的应用.在电照相领域,近年发展起来的新一代带有计算机控制、数字扫描、激光成像的激光打印系统,具有分辨率高,印刷质量好,印刷速度快等特点,这种半导体激光打印系统的关键部件,是有机光导(OPC)鼓.     

激光散射法研究蛋白质与氨比西林钠盐的相互作用

用动态和静态激光散射法研究了在25±0.1℃, 离子强度0.085 mol·kg^-1, pH 7.4, 5.8, 4.9条件下人血清白蛋白和氨比西林钠盐相互作用所形成的复合物. 静态激光散射结果表明, 在pH 7.4, 5.8, 4.9条件下, 蛋白质和药物分子所形成复合物的分子量分别为: 210000, 418000, 448000 g·mol^-1; 均方旋转半径和第二维里系数随pH值降低而减小. 动态激光散射给出了不同pH条件下体系的扩散系数和粒径分布信息. 结果表明, 蛋白质/药物复合物体系有宽窄兼容的流体力学直径分布, 体系的扩散系数随pH值和氨比西林钠盐浓度的变化而变化.     

高分子荧光微球在生物医学领域中的某些应用

新近发展的高分子微球具有粒度均一、稳定性好、可连接多种生物活性物质从而便于多参数分析等优点，在生物医学领域有广泛的应用。本文主要阐述了高分子荧光微球在免疫分析、高通量药物筛选、药物载体、固定化酶、细菌和病毒诊断、单个核苷酸多态性基因型、细胞因子鉴定以及单绌胞分析等方面的应用，并简介了某些最新进展。     

激光诱导击穿光谱(LIBS)技术在低碳钢铁冶金行业的应用

激光诱导击穿光谱技术(Laser induced breakdown spectroscopy,简称LIBS)是一种基于激光等离子体的发射光谱技术,具有样品制备简单,分析迅速,多元素同时分析,现场在线和远程分析等独特优势,已在钢铁冶金领域取得了越来越广泛的应用与发展。综述了近年来LIBS技术在钢铁冶金领域的应用研究进展,从冶金生产的全流程进行介绍,包括矿石、熔融钢水/铁水、钢铁产品及炉渣和废气分析。同时,还总结了LIBS技术在钢铁冶金领域应用的优点和缺点,并对该技术的应用前景及未来发展方向进行展望。     

温敏性微凝胶的研究技术

温敏性微凝胶因具有尺寸小、对温度的变化响应速度快、渗透性好等优点,所以在许多领域显示出良好的应用前景.温敏性微凝胶的应用性能取决于由其结构所决定的物理化学性能.为了深入了解温敏性微凝胶的结构与性能关系,研究人员利用不同技术手段进行了广泛研究.本文主要综述了显微技术、示差扫描量热技术、光散射技术、中子散射技术、核磁共振及荧光光谱等在温敏性微凝胶结构与性能研究中的应用、主要研究结果,并对微凝胶未来的研究方向提出了一些建议.     

MALDI-TOF-MS在生物化学和高分子化学中的应用

基质辅助激光解吸电离飞行时间质谱(MALDI-TOF-MS)这一先进技术是80年代末发展起来的一个质谱学分支,它的诞生无疑为国内诸多领域注入了一丝新鲜的活力.自从带基质的激光解吸电离飞行时间质谱技术问世以来,具有良好的"软电离"性质对杂质的包容性以及可直接分析混合物而无需预先分离等特点,已广泛地应用于生物化学、高分子化学、有机化学、金属有机化学、药学等领域,显示出独特的潜力和应用前景.本文讨论了MALDI-TOF-MS技术在生物化学和高分子化学领域中的应用.     

Light scattering and transmission studies of nanofiller particulate size,matrix cavitation,and high strain interfacial dewetting behavior in silica‐elastomer composites

The effect of silica nanofiller surface chemistry on compounded particle size and high strain particle dewetting in a semitransparent nanosilica‐filled elastomer composite was determined using backscattered visible light and transmitted light, respectively. The integrated intensities of backscattered light from the samples were collected at various visible wavelengths for thin‐film composites using ultraviolet–visible spectrometer with an integrating sphere. The data revealed strong Rayleigh‐type scattering from compounded filler particles. Size information was extracted and found to broadly correlate with scanning electron microscopy image analysis of fracture surface. Incorporation of a siloxane surface treatment chemical during compounding resulted in a reduced average filler particle size in the cured composite. On extension of the samples, an optical transition was observed only in the filled composites. At high strains, the semi transparent samples displayed an abrupt drop in transparency becoming opaque. This was quantified using a simple light transmission‐sample extension technique. Strain‐induced crystallization was discounted as the cause for the transition by X‐ray diffraction analysis. The onset yield stress for the optical transition was found to be filler surface‐chemistry‐dependent with the siloxane‐treated filler exhibiting a greatly increased onset stress value. These observations were discussed and rationalized in terms of filler particle–matrix dewetting and cavitation at high strains. Matrix–filler dewetting was distinguished from matrix cavitation by comparison with Beer–Lambert behavior derived from unstrained samples. © 2011 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys, 2011.     

Enhanced Characterization of Naproxen Formulation by Near Infrared Spectroscopy

Near infrared spectroscopy in combination with appropriate chemometric methods is an effective technique for quantitative analysis of parameters of interest for the pharmaceutical industry. In this study, the artificial neural network (ANN) was applied to monitor critical parameters (compression force, tablet hardness, mean particle size, and active pharmaceutical ingredient concentration of tablets) in the process of naproxen pharmaceutical preparation. The performance of ANN was compared to linear methods (partial least squares regression (PLS) and synergy interval partial squares (siPLS)). The ANN models for compression force, tablet hardness, mean particle size, and active pharmaceutical ingredient concentration of tablets yielded the low root mean square error of prediction (RMSEP) values of 0.936 KN, 0.302 kg, 4.49 mg, and 2.14 µm, respectively. The predictive ability of the PLS model was improved by siPLS with selection of spectral regions and the best performance among all calibration methods was showed by the nonlinear method (ANN). Effective models were built by using these approaches using near infrared spectroscopy.     

Green Synthesis of Gold,Iron and Selenium Nanoparticles Using Phytoconstituents: Preliminary Evaluation of Antioxidant and Biocompatibility Potential

This study aimed at fabricating gold (Au), iron (Fe) and selenium (Se) nanoparticles (NPs) using various natural plant extracts from the Fertile Crescent area and evaluating their potential application as antioxidant and biocompatible agents to be used in the pharmaceutical field, especially in drug delivery. The Au-NPs were synthesized using Ephedra alata and Pistacia lentiscus extracts, whereas the Fe-NPs and Se-NPs were synthesized using peel, fruit and seed extracts of Punica granatum. The phytofabricated NPs were characterized by the UV-visible spectroscopy, scanning electron microscope, Fourier transform infrared spectroscopy, X-ray diffraction (XRD) and energy-dispersive X-ray (EDS) spectroscopy. Scanning electron microscope technique showed that the synthesized NPs surface was spherical, and the particle size analysis confirmed a particle size of 50 nm. The crystalline nature of the NPs was confirmed by the XRD analysis. All synthesized NPs were found to be biocompatible in the fibroblast and human erythroleukemic cell lines. Se-NPs showed a dose-dependent antitumor activity as evidenced from the experimental results with breast cancer (MCF-7) cells. A dose-dependent, free-radical scavenging effect of the Au-NPs and Se-NPs was observed in the DPPH (2,2-Diphenyl-1-picrylhydrazyl) assay, with the highest effect recorded for Au-NPs.     

现代分析技术在药物分析中的研究与应用

综述了国内外近年来共振瑞利散射法、原子吸收光谱法、磷光光谱法和质谱联用技术在药物分析中的研究与应用.从反应条件、线性范围、灵敏度等方面介绍了4类方法对不同反应体系的研究现状,展望了药物分析的发展方向.     

A simple and rapid method for the determination of particle size in emulsions from ultrasound data

Oil droplet size in emulsions can be determined from ultrasound velocity and attenuation spectra. We show that explicit solutions of the acoustic scattering matrix may be used to rapidly calculate a mean particle size for a limited but useful range of particle sizes. Our technique is well suited to in-line measurement. Both modelling and experiment indicate that the main scattering mechanism is thermal scattering. Calculations using the explicit solutions have been compared with experimental results from sunflower oil-in-water emulsions.     

Synthesis and catalytic properties of microemulsion-derived cerium oxide nanoparticles

The synthesis of cerium dioxide nanoparticles using an inverse microemulsion technique and precipitation method was investigated. Cerium hydroxide nanoparticles were synthesized by adding diluted ammonia to n-heptane–surfactant–cerium nitrate system. The micelle and particle size in the range of 5–12 nm were controlled by varying the molar water to surfactant ratio and analyzed by dynamic light scattering (DLS), small angle X-ray scattering (SAXS) and high-resolution transmission electron microscopy (HRTEM). Cerium hydroxide nanoparticles were isolated and subsequently treated at 100–600 °C to obtain nanoscale ceria. Crystallite sizes of cerium dioxide in the range of 6–16 nm were estimated by Scherrer analysis by X-ray diffraction (XRD) and HRTEM. The catalytic activity of particles annealed at 400 and 600 °C in soot combustion reactions was characterized by temperature-programmed oxidation (TPO) indicating a size-dependant activity. Crystallite sizes and catalytic stability of elevated ceria systems were tested in second combustion cycles.     

软化学技术合成高容量锂二次电池正极材料AgV3O8

应用软化学方法合成层状AgV3O8正极材料,并用XRD(粉末X-射线衍射)、SEM(扫描电子显微镜)和LPSA(激光粒度分析)表征了材料的结构和形貌,采用恒流充放电技术研究了其电化学性能.SEM和LPSA测试结果显示所制备的材料具有较小的颗粒尺寸和较窄的粒度分布区间.恒流充放电测试结果表明,该材料具有高的放电比容量,其中400℃下获得的材料首次放电容量高达760.5 mAh/g.     

Analysis of ochres from Clearwell Caves: the role of particle size in determining colour

Three ochre samples (A (orange-red in colour), B (red) and C (purple)) from Clearwell Caves, (Gloucestershire, UK) have been examined using an integrated analytical methodology based on the techniques of IR and diffuse reflectance UV-visible-NIR spectroscopy, X-ray diffraction, elemental analysis by ICP-AES and particle size analysis. It is shown that the chromophore in each case is haematite. The differences in colour may be accounted for by (i) different mineralogical and chemical composition in the case of the orange ochre, where higher levels of dolomite and copper are seen and (ii) an unusual particle size distribution in the case of the purple ochre. When the purple ochre was ground to give the same particle size distribution as the red ochre then the colours of the two samples became indistinguishable. An analysis has now been completed of a range of ochre samples with colours from yellow to purple from the important site of Clearwell Caves.     

核壳结构PS/CeO2复合微球的制备及其在化学机械抛光中的应用

以原位化学沉淀的方法制备了不同粒径、包覆结构PS(核)/CeO2(壳)复合微球,利用X射线衍射仪、透射电子显微镜、选区电子衍射、场发射扫描电子显微镜、能谱分析仪、Fourier转换红外光谱仪、热失重分析仪和ζ电位测定仪等手段对所制备样品的微观结构进行了表征。将所制备的复合微球用做磨料,考察其对二氧化硅介质层的抛光性能,用原子力显微镜观察和测量抛光表面的微观形貌、轮廓曲线和粗糙度。结果表明,所制备的PS/CeO2复合微球具有核壳包覆结构,粒径分别约为140,180和220 nm,PS内核被粒径约为5 nm的CeO2颗粒均匀包覆。AFM结果显示,复合磨料的粒径越小,抛光后表面粗糙度越低;且酸性(pH=3)比碱性(pH=10)抛光浆料具有更好的抛光效果。     

Structure of Nano‐sized CeO2 Materials: Combined Scattering and Spectroscopic Investigations

The structure of several nano‐sized ceria, CeO₂, systems was investigated using neutron and X‐ray diffraction and X‐ray absorption spectroscopy. Whilst both diffraction and total pair distribution functions (PDFs) revealed that in all of the samples the occupancy of both Ce⁴⁺ and O^2? are very close to the ideal stoichiometry, the analysis using Reverse Monte Carlo technique revealed significant disorder around oxygen atoms in the nano‐sized ceria samples in comparison to the highly crystalline NIST standard. In addition, the analysis revealed that the main differences observed in the pair correlations from various X‐ray and neutron diffraction techniques were attributable to the particle size of the CeO₂ prepared by the reported three methods. Furthermore, detailed analysis of the Ce L₃‐ and K‐edge EXAFS data support this finding; in particular the decrease in higher shell coordination numbers with respect to the NIST standard, is attributed to differences in particle size.