Morphological changes induced in erythrocyte membrane by the antiepileptic treatment: An atomic force microscopy study

Atomic force microscopy (AFM), a powerful characterization tool widely applied in problems in a large range of disciplines of the natural sciences, including cellular biology, was used to obtain information about the morphological changes induced in the erythrocyte membrane at the patients with epilepsy that undergo a long time treatment that operates upon one or several neuronal ionic channels, comparative with a healthy donor. This technique allowed non‐invasive imaging of erythrocyte membrane, revealing details and specific characteristics down to the nanometer level with characterization of surface texture parameters, such as average height, average roughness and coefficient of kurtosis at micrometer/nanometer resolution. For the healthy donor the AFM morphology appears to have all the characteristics of a normal red blood cell membrane. Instead, the closer examination of the erythrocytes membrane surface morphology for the samples collected from the patients diagnosed with epilepsy and treated with specific drugs did not reveal similar structures with those obtained for the healthy donor. The nanostructure of the membrane was drastically damaged, depending on the administrated treatment, and probably in time will affect their functionality. Therefore, the anticomital drugs have influence not only at the neuronal level, but also at the red blood cell level.     

预制混凝土小型空心砌块施工实践

随着建筑节能墙体的推广 ,预制混凝土小型空心砌块在承重墙体中得到了广泛应用。就此阐述了小型空心砌块的施工要点、质量控制措施、成品保护等 ,提出小型空心砌块对节能与节土有重要意义     

氢化物双道无色散原子荧光法同时测定化探样品微量硒、碲

在硝酸、高氯酸、硫酸溶矿方法的基础上，作者用硝酸、氢氟酸溶矿，高氯酸冒烟，趁热加入浓盐酸将硒、碲还原成低价；用三价铁盐消除铜等元素的干扰，以氢化物双道原子荧光法同时测定化探样品中的硒和碲。经国家一级标样验证，这种方法简便可靠，具有较高的灵敏度。硒、碲的检出限分别为：ｗ（Ｓｅ）／１０（－６）＝０．０１，ｗ（Ｔｅ）／１０（－６）＝０．００８。     

自由弛豫信号截取时长对NMOR铷原子磁力仪性能的影响

基于非线性磁光旋转(nonlinear magneto-optical rotation, NMOR)效应的铷原子磁力仪通过特定时长的自由弛豫正弦振荡信号可获得拉莫尔进动频率和外磁场值,因此自由弛豫信号的截取时长能够影响原子磁力仪的性能指标。重点研究了在500 nT背景磁场条件下自由弛豫信号截取时长对原子磁力仪灵敏度和磁场测量值的影响。测量结果表明,用噪声功率谱方法标定的灵敏度指标随着自由信号截取时长的增加逐渐减小并趋于稳定,约0.2 pT/Hz~(1/2);交变磁场实验表明该磁力仪所得的磁场值是特定截取时长内磁场波动的平均。因此本文NMOR原子磁力仪所得的高灵敏度指标一定程度上是通过数学方法平均了自由弛豫信号截取时长内的磁场值波动。该方法对其他原子磁力仪或实验装置灵敏度的标定和磁场测量值的分析具有一定的借鉴意义。     

硅微通道板微加工技术研究

微通道板(MCP)是二维通道电子倍增器,广泛用于电子、离子、紫外辐射和X-射线的探测与成像。提出一种硅微通道板(Si-MCP)制备工艺,分别采用干法刻蚀和电化学腐蚀微加工技术制备了硅微通道阵列（SMA）。重点研究了硅感应耦合等离子体刻蚀和光电化学腐蚀的特性,结果表明：硅光电化学腐蚀技术易于制备高长径比微通道,微通道侧壁更光滑、可制备倾斜通道、更适合制备Si-MCP. 制备出通道周期为6 μm、长径比大于50的SMA结构。采用厚层氧化实现了Si-MCP基体绝缘,采用原子层沉积工艺制备了连续倍增极,制作出Si-MCP样品。测试结果表明,采用半导体微加工技术制备的Si-MCP电子增益特性具有可行性。     

氢化物发生原子荧光法和无火焰原子荧光法连续测定地球化学样品中的As、Sb、Bi、Hg

建立了一种连续测定Ａｓ、Ｓｂ、Ｂｉ、Ｈｇ四元素的方法。对测汞用还原剂及几种测量体系进行了比较，采用对原子化器适当加温的无火焰原子荧光法测汞，以ＫＭｎＯ４消除Ｔｅ、Ｓｅ对汞测定的干扰。本方法Ａｓ、Ｓｂ、Ｂｉ、Ｈｇ四元素的检出限分别为２．０１×１０－１０ｇ／ｍｌ、１．５６×１０－１０ｇ／ｍｌ、２．９８×１０－１０ｇ／ｍｌ；４．２×１０－１１ｇ／ｍｌ；对ＧＳＳＩ平行测定１１次，Ｈｇ的标准偏差为２．１％；对含Ａｓ、Ｓｂ、Ｂｉ为１０×１０－９ｇ／ｍｌ、１．０×１０－９ｇ／ｍｌ、１０×１０－１０ｇ／ｍｌ的溶液平行测定１１次，其ＲＳＤ分别为１．３７５％、１．３８６％和２．３３９％；经对地球化学标准物质及批量样品分析证明，结果满足要求。     

煤矸石颗粒破碎及其对工程力学特性影响研究

对徐州北部地区路用煤矸石的基本粒度特性及其颗粒破碎细化规律进行了试验研究,并综合分析了其对各种工程力学特性的影响,主要是压实、渗透、水稳、压缩、承载、变形与强度特性等。在此基础上,提出了适合于煤矸石的强度与变形本构模型。     

Use of 8-hydroxyquinoline-chitosan chelating resin in an automated on-line preconcentration system for determination of zinc(II) by F AAS

This study presents the development of an on-line preconcentration system for zinc(II) determination in aqueous samples. The analyte was trapped in a mini-column filled with a chelating resin based on a chitosan biopolymer modified with 8-hydroxyquinoline obtained by the diazotization reaction. Flow and chemical variables of the system, as well as the potential interference ions, were optimized through a multivariate procedure. The factors selected were sample pH, eluent concentration (HNO(3)), and sample and eluent flow rates. It was verified through a full factorial design that the sample pH and eluent flow rate factors were statistically significant at the 95% confidence level. A final optimization of the significant factors was carried out using a Doehlert matrix. The preconcentration system was linear between 2.5 and 75 microgL(-1), with a regression coefficient of 0.9995. The enrichment factor was 17.6. The limits of detection and quantification were 0.8 and 2.5 microgL(-1), respectively. The repeatability and the analytical frequency were, respectively, 2.7 (25.0 microgL(-1), n=8) and 18 samples per hour. Results for recovery tests using mineral water samples were between 85 and 93%. Certified reference materials were analyzed in order to check the accuracy of the proposed method.     

Slurry analysis after lead collection on a sorbent and its determination by electrothermal atomic absorption spectrometry

In this study, in order to eliminate the drawbacks of elution step and to reach higher enrichment factors, a novel preconcentration/separation technique for the slurry analysis of sorbent loaded with lead prior to its determination by electrothermal atomic absorption spectrometry was described. For this purpose, at first, lead was collected on ethylene glycol dimethacrylate methacrylic acid copolymer (EGDMA-MA) treated with ammonium pyrolidine dithiocarbamate (APDC) by conventional batch technique. After separation of liquid phase, slurry of the sorbent was prepared and directly pipetted into graphite furnace of atomic absorption spectrophotometer. Optimum conditions for quantitative sorption and preparation of the slurry were investigated. A 100-fold enrichment factor could be easily reached.

The analyte element in certified sea-water and Bovine-liver samples was determined in the range of 95% confidence level. The proposed technique was fast and simple and the risks of contamination and analyte loss were low. Detection limit (3δ) for Pb was 1.67 μg l⁻¹.     

中国放射性同位素技术与应用进展

介绍了中国放射性同位素与应用的发端,论述了放射性同位素及其制品的研发、生产、应用进展以及未来的发展前景.