稳定同位素在药物动力学研究中的新进展

综述了稳定同位素在药物动力学研究中的最新发展，随着质谱和色－质联用等仪器的普及，它将成为药物研究中的一种重要手段． The recent progress of the Stable Isotopes(SI) research on pharmacokinetics is reviewed. With development of MS and GC MS, it will be an important method for studying drugs.     

现代物理技术在铜鼓研究中的应用

本文通过矿料来源的铅同位素考证、铜鼓声学特性研究、铜鼓调音刮痕探秘几个实例，介绍现代物理技术在古代铜鼓研究的具体应用，从而说明物理学在考古学中的应用大有可为。     

稳定性同位素评价南方膳食结构中铁的吸收率

评价南方膳食结构中铁的吸收率,为我国不同人群、不同膳食类型的铁吸收率提供参考资料。采用~(57)Fe-EDTA或~(57)FeSO4两种铁的稳定性同位素示踪方法,以稀土元素Dy作为排泄物的回收标记物,于现场进行人体代谢试验,受试者为健康成年男子和孕龄妇女各10名,分6次口服3.0mg的~(57)Fe稳定性同位素示踪剂及2.0mg的Dy,粪便监测法收集同位素排出粪样;用电感耦合等离子体质谱仪测定粪样~(57)Fe/~(56)Fe的比值,用原子吸收光谱法测定粪样总Fe,从而计算该人群膳食铁的吸收率。在南方膳食结构中,口服~(57)Fe-EDTA示踪剂,成年男子膳食铁的吸收率为7.34%,孕龄妇女的吸收率为6.92%;口服~(57)Fe-SO4示踪剂,成年男子膳食铁的吸收率为6.01%,孕龄妇女的吸收率为5.40%。本研究结果表明口服~(57)Fe-EDTA评价膳食铁吸收率虽有高于用~(57)FeSO4评价结果的趋势,但无显著性统计分析差异。中国南方城市膳食中铁的吸收率与2000年中国营养学会对我国居民膳食铁吸收率的估计水平大致相当。     

催化光度法测定痕量铁的研究

本文研究了在ｐＨ４．５的ＨＡｃ－ＮａＡｃ介质中，有非离子表面活性剂ＴｒｉｔｏｎＸ－１００存在下，痕量铁催化水中溶解氧氧化双硫腙褪色的指示反应，建立了胶束增溶催化动力学光度法测定痕量铁的新方法。方法的线性范围为０－１．５μｇ／２５ｍＬ，检出限为１．６×１０￣（－１０）ｇ／ｍＬ。用于人发中痕量铁的测定，结果满意。     

PAR-吖啶黄能量转移荧光猝灭法测定痕量铁(Ⅱ)的研究

对 4 (2 吡啶偶氮 ) 间苯二酚 (PAR)与吖啶黄间荧光能量转移进行了探讨 ,研究了其能量转移的最佳条件 ,并应用该体系测定痕量铁 (Ⅱ ) ,由此建立了能量转移荧光测定痕量铁的新方法。在λex/em =46 5nm/5 0 5nm ,十二烷基硫酸钠 (SDS)作用下 ,pH =9 2时 ,吖啶黄与PAR 铁 (Ⅱ )络合物间能发生有效能量转移 ,使吖啶黄的荧光猝灭。铁的量在 0～ 10 μg·L-1范围内呈良好的线性关系。最低检出限 0 0 6 μg·L-1。该方法用于水样、发样中痕量铁的测定 ,结果满意。     

Methane-Derived Carbonates in a Native Sulfur Deposit: Stable Isotope and Trace Element Discriminations Related to the Transformation of Aragonite to Calcite

Abstract

Stable isotope (¹³C, ¹⁸O, ³⁴S) and trace element (Sr²⁺, Mg²⁺, Mn²⁺, Ba²⁺, Na⁺) investigations of elemental sulfur, primary calcites and mixtures of aragonite with secondary, post-aragonitic calcite from sulfur-bearing limestones have provided new insights into the geochemistry of the mineral forming environment of the native sulfur deposit at Machów (SE-Poland). The carbon isotopic composition of carbonates (δ¹³C = ?41 to ?47‰ vs. PDB) associated with native sulfur (δ³⁴S = + 10 to + 15‰ vs. V-CDT) relates their formation to the microbiological anaerobic oxidation of methane and the reduction of sulfate derived from Miocene gypsum. From a comparison with experimentally derived fractionation factors the element ratios of the aqueous fluids responsible for carbonate formation are estimated. In agreement with field and laboratory observations, ratios near seawater composition are obtained for primary aragonite, whereas the fluids were relatively enriched in dissolved calcium during the formation of primary and secondary calcites. Based on the oxygen isotope composition of the carbonates (δ¹⁸O = ?3.9 to ?5.9‰ vs. PDB) and a secondary SrSO₄ (δ¹⁸O = + 20‰ vs. SMOW; δ³⁴S = + 59‰ vs. V-CDT), maximum formation temperatures of 35°C (carbonates) and 47°C (celestite) are obtained, in agreement with estimates for West Ukraine sulfur ores. The sulfur isotopic composition of elemental sulfur associated with carbonates points to intense microbial reduction of sulfate derived from Miocene gypsum (δ³⁴S ≈ + 23‰) prior to the re-oxidation of dissolved reduced sulfur species.     

火焰原子吸收光度法直接测定铝合金中铁基体干扰的研究

采用火焰原子吸收光度法直接测定铝合金中的铁时，溶液的酸度、共存的铝基及硅等元素严重干扰铁的测定，本文对铝合金中各种共存元素对铁测定的干扰进行了研究，发现通过控制酸度，加入适当的基体改进剂，配制以铝为基体的校准曲线，可以解决基体干扰的问题。方法的灵敏度、精密度、回收率好，实用性强。     

交联壳聚糖在硒的形态分析中的应用研究

本文研究了交联壳聚糖对Ｓｅ（Ⅳ）和Ｓｅ（Ⅵ）的吸附行为,并吸附机理进行了探讨。结果表明：在ＰＨ＝４时,Ｓｅ（Ⅳ）捐附率达９５％,而对Ｓｅ（Ⅳ）几乎无吸附;吸附Ｓｅ（Ⅵ）后,用１ｍｏｌ／Ｌ盐酸定量解吸,建立了氢化物发生原子吸收测定环境中痕量Ｓｅ（Ⅳ）／Ｓｅ（Ⅵ）和有机硒的方法。本法的检出限为２０ｎｇ／Ｌ,回收率为９３－１０６％,变异系数为２．０－５．０％     

微量元素示踪法在古代青铜器铜矿料来源研究中的应用

青铜模拟熔铸实验表明,利用ICP-AES法测定的青铜中亲铜元素的成分数据,通过聚类分析,可以较好地区分不同产地的铜矿料及其青铜产物。文章将这一方法具体应用于盘龙城商代遗址和鄂州出土青铜器的微量元素数据的分析,以考察其可行性和应用价值。多元统计分析结果显示：青铜模拟熔铸实验所得结论,亦可应用于盘龙城和鄂州青铜器铜矿料的区分,进一步验证了微量元素示踪古代青铜器铜矿料来源的可行性。     

High Field ESR System and Its Application to the Study of Quantum Spin Systems

Developments of the high field ESR system in Kobe University is presented. Using Gunn oscillators and backward traveling oscillators (BWO), we can cover the frequency region from 30 to 1183.6 GHz with the use of InSb detector. Pulsed magnetic field up to 30 T is available and we are now trying to extend the field up to 40 T. Temperature range is from 1.8 to 300 K. Using this system, we studied S=1/2 ladder like system Cu₂(C₅H₁₂N₂)₂Cl₄, and found a new magnetic transition at 10.1 T at 1.8 K. The temperature dependence of ESR in Cu₂(C₅H₁₂N₂)₂CI₄ shows g-shift below 8 K which corresponds to the maximum of the magnetic susceptibility. The g-shift below 8 K suggests the increase of the quantum fluctuation in the system, and the role of the quantum fluctuation in Cu₂(C₅H₁₂N₂)₂CI₄ is discussed.     

Multivariate Image Analysis of Magnetic Resonance Images with the Direct Exponential Curve Resolution Algorithm (DECRA): Part 2: Application to Human Brain Images

Owing to the heterogeneity of living tissues, it is challenging to quantify tissue properties using magnetic resonance imaging. Within a single voxel, contributions to the signal may result from several types of¹H nuclei with varied chemical (e.g., −CH₂−, −OH) and physical environments (e.g., tissue density, compartmentalization). Therefore, mixtures of¹H environments are prevalent. Furthermore, each unique type of¹H environment may possess a unique and characteristic spin–lattice relaxation time (T₁) and spin–spin relaxation time (T₂). A method for resolving these unique exponentials is introduced in a separate paper (Part 1. Algorithm and Model System) and uses the direct exponential curve resolution algorithm (DECRA). We present results from an analysis of images of the human head comprising brain tissues.