电感耦合等离子体质谱法同时测定地质样品中锗碘

样品用NaOH全熔,热水提取,分取部分溶液通过强酸性阳离子交换树脂,分离溶液中大量的钠离子后,采用电感耦合等离子体质谱法同时测定锗和碘。方法的检出限Ge、I分别为0.043μg/g和0.22μg/g,经土壤国家一级标准物质分析验证,结果与标准值相符,12次测定的RSD均小于10%。     

分光光度法测定土壤中碘的方法改进

应用电感耦合等离子体质谱法(ICP-MS)测定地球化学调查样品中的碘,主要采用封闭溶样、混合酸溶、碱熔和半熔法进行样品处理,但由于碘在土壤和沉积物中的存在形态较为复杂,有高碘酸根、碘酸根、碘离子,且碘为卤族元素,第一电离能较高,在样品处理及上机测定环节中存在溶出不彻底、记忆效应强、稳定性较差等问题。本文采用碳酸钠-氧化锌半熔法处理样品,乙醇-沸水提取后用732型阳离子交换树脂将溶液中大量阳离子分离,采用内标法ICP-MS测定样品溶液中的碘。通过优化溶样程序提升了样品溶出效果,优化测定介质及内标元素消除记忆效应,提升了结果稳定性,建立了一套完善的ICP-MS测定碘的方法。使用土壤和沉积物国家一级标准物质进行方法验证,方法检出限为0.045μg/g,方法检测下限为0.15μg/g,方法精密度(RSD,n=12)≤5.93%,方法准确度△logC≤0.01,符合地球化学调查样品分析测试要求,可推广应用于地球化学调查中大批量土壤和沉积物样品的分析测试。

     

对比剂注射方案优化联合低管电压在主动脉CTA中的探讨

目的：探讨对比剂注射方案优化联合低管电压在主动脉CT血管成像（CTA）中应用的可行性。方法：临床行主动脉CTA检查患者80例,根据对比剂碘浓度及管电压分为A、B两组（n=40）,A组根据对比剂碘浓度及注射速率分A1组和A2组（n=20）。A1组,注射300 mgI/mL北陆碘海醇溶液、注射速率4 mL/s,管电压100 kV;A2组,注射300 mgI/mL北陆碘海醇溶液、注射速率3.5 m L/s,管电压100 k V。B组,注射350 mgI/mL北陆碘海醇溶液、注射速率3.5 m L/s、管电压120 k V。其他扫描参数,注射对比剂容量,重建方式,自动管电流调节技术一致。采用两独立样本t检验（非正态分布采用Mann-Whitney U检验）来比较两组的临床资料、CT的辐射剂量、主观及客观评价图像质量等指标。结果：A组与B组比较,在年龄、性别、体质量指数（BMI）均无统计学差异（P>0.05）;在图像质量上主观评价及客观评价亦无统计学意义（P>0.05）,B组CNR优于A组均达到诊断要求,测量主动脉各段的CT值均>300 HU;A组与B组辐射剂量有显著统计学意义（P<0.05）,A组比B组有效辐射剂量（ED）降低了17.73%;在对比剂碘含量上A组比B组减少了14.29%。结论：注射300 mgI/mL碘海醇溶液、注射速率3.5 m L/s联合低管电压（100 kV）在主动脉CTA检查中取得了满意的图像质量,为临床提供了精准诊断依据,不仅降低了辐射剂量,还降低了碘含量。     

艾斯卡试剂熔矿、动态树脂交换——等离子体质谱法测定土壤样品中的痕量碘

研究了电感耦合等离子体质谱法（ICP—MS）测定土壤样品中微量碘的可行性,对测定碘的条件作了部分改进及进一步优化。样品经艾斯卡试剂分解,热水提取,阳离子交换树脂动态分离溶液中大量的钠、铁、锌等阳离子,干过滤部分溶液,采用电感耦合等离体子质谱法（ICP—MS）直接测定溶液中的碘。本方法用国家标准物质进行验证,测定结果和标准值吻合。并用该法顺利完成了陕西省宝鸡地区多目标区域地球化学调查样品中碘的测定。     

探讨肘部固定夹板应用于CT增强患者的临床价值

目的:探讨肘部固定夹板应用于CT增强患者中的临床实际价值。对象与方法:将预做CT增强检查的120例患者,随机分为对照组(60例)和观察组(60例)。对照组所有患者在进行CT增强检查前肘关节部位不使用肘部固定夹板;观察组所有患者在进行CT增强检查前肘关节部位使用肘部固定夹板,比较两组患者碘对比剂渗漏的发生率及护理服务满意度。结果:对照组60例患者中发生渗漏10例,发生率为16.7%,护理服务满意度80%。观察组60例患者中发生渗漏2例,发生率3.3%,护理服务满意度95%。观察组碘对比剂渗漏的发生率明显低于对照组,而护理服务满意度优于对照组,两组比较差异具有统计学意义(P0.05)。结论:肘部固定夹板应用于CT增强患者时,明显降低了碘对比剂渗漏发生率,并提升了护理服务满意度。患者很容易接受,值得临床推广应用。     

Intensive sampling of iodine and nutrient speciation in naturally eutrophicated anchialine pond (Rogoznica Lake) during spring and summer seasons

A study of inorganic iodine speciation in the water column of a naturally eutrophicated anchialine pond (Rogoznica Lake, East Adriatic Coast) was conducted in a period between April and July 2004 to obtain information how close the inorganic iodine system is to that of inorganic nutrients during spring, when phytoplankton activity is at maximum, and how the system changes up to summer, when highly reducible redox-conditions prevail in deep water.     

Determination of Iodine in Thirty Two International Geochemical Reference Materials

Thirty two geochemical reference samples have been analysed for their iodine contents by a pyrohydrolysis extraction technique, followed by colourimetry. In spite of the existence of few reported values for iodine, limiting comparison with results from this study, the four available "reference" values show good agreement with the work reported here.     

生物和环境样品中痕量溴碘的小体积交换分离与测定

针对微克量级卤素的分离问题,研究了不同形态卤素在７１７阴离子交换柱上的吸附特点。通过离子交换柱的改进和分离条件的选择,实现了卤素与基体以及卤素之间的有效分离。洗脱体积小,盐份浓度低,经水样、土壤和生物样品分析考查,方法可行。     

Molecular iodine reduction by natural and model organic substances in seawater

The reactivity of 2 µM molecular iodine in seawater toward various organic compounds containing aromatic, -keto, amino, olefinic and sugar functional groups was investigated. More detailed studies have been made of the reduction kinetics with salicylic acid, -ketoglutaric acid and the polypeptide oxidized glutathione, particularly to establish whether variation over the pH range 4–9 would provide a similar reduction reactivity or fingerprint to that of molecular iodine added to natural seawater. The data indicates that compounds with only one functional group react with first order kinetics whereas compounds with multiple functional groups show more complex behaviour. Kinetic and thermodynamic modelling indicates that HOI is the main iodine species reacting with organic matter at seawater pH of 8.2. Based on the pH fingerprints, peptides and compounds containing carbonyl or -keto groups are the key reductants of molecular iodine added to seawater. These compounds form C-I and N-I bonds which can allow for a rich organic iodine chemistry in seawater. The model compound results are discussed in relation to oceanic processes.     

Iodine content ofSargassum in Southern China

Sodium thiosulphate and neutron activation determination of iodine content in samples of 18Sargassum species collected in Guangdong and Guangxi Province in April 1996 showed large differences (0.47×10⁻³ inSargassum hemiphyllum, 0.56×10⁻³ inSargassum assimile, and 4.5×10⁻³ inSargassum vachellianum). Traditional titration analysis and neutron activation analysis for determination of total iodine yielded similar results showing that certainSargassum species had high capacity to accumulate iodine. Contribution No. 3162 from the Institute of Oceanology, Chinese Academy of Sciences. The project was supported by the National Ninth Five-Year Plan of China (No. 96-916-04-01).