Distribution of 14 elements in tissues and organs of oceanic seabirds

The concentrations of 14 trace elements (Li, V, Mn, Co, Cu, Zn, Se, Rb, Sr, Ag, Cd, Cs, Pb, and Hg) were determined in tissues and organs of three species and in the liver of 11 species of seabirds. Comparatively high concentrations of Li, Co, Sr, and V were found in the femur. Cd, Se, Cu, and Mn concentrations were relatively higher in the kidney than in other tissues and organs. Rb, Cs, and Pb concentrations were rather uniform among tissues. Concentrations of essential elements such as Mn, Cu, and Co were comparable among seabird species, except high Cu concentrations in northern giant petrel. Among nonessential elements, concentrations of Cd and Hg were variable according to seabird species. Pb levels were low in all the species. High Se levels (100 microg/g dry weight) were found in the liver of black-footed albatross and grey petrel. There were significant positive correlations between Se and Cd concentrations in three species and between Se and Hg in black-footed albatross, suggesting that Se has an antagonistic action on the toxic effects of Cd and Hg. Concentrations of Li, V, Ag, and Cs were usually low (less than 1 microg/g dry weight).     

大宝山矿区多金属硫化物矿床中共生(伴生)元素的分布特点及综合利用前景分析

大宝山是一个大型的多金属复合矿床,并含多种共生(伴生)元素,综合利用价值很大.研究和分析多金属硫化物矿床中伴生元素的含量、赋存状态、嵌布特点、分布规律,是综合利用的前提.     

Single and complex effect of ammonia and hydrogen sulfide in the air on small laboratory animals (rats) under various environmental conditions 2. Effect of hydrogen sulfide alone and hydrogen sulfide with ammonia and dust

The maximum tolerable concentrations per animal position of hydrogen sulphide alone (5 ppm) and with ammonia (5 ppm H2S; 30 ppm NH3) were established by model experiments under defined environmental conditions. The normal values of the contaminant gas combination were found to be acceptable even with additional dust load on the experimental animals. TGL 29084 should stipulate 5 ppm hydrogen sulphide as the new maximum concentration per animal position.     

Distribution of alloying elements and impurities in the secondary zinc alloy after filtration

Influence of the ceramic foam filter composition on the microstructure and distribution of alloying elements (copper and aluminum) and impurities (iron and lead) in the secondary zinc alloy is investigated. The foam-ceramic filters (FCF) on the basis of corundum, cordierite and silicon carbide with ultradispersed active layers are investigated. By the methods of metallographic, X-ray diffraction and X-ray spectral analyses it is demonstrated that the filtration through the foam-ceramic filters allows one to obtain a homogeneous alloy with the uniform distribution of the alloying elements and impurities. It has been revealed that the highest effect on the microstructure and characteristics of the alloy exert the filters based on cordierite and silicon carbide with an ultradispersed layer including the elements of IV group of the Periodic System.     

On interactions amongst trace and alloying elements at the grain boundaries of a low alloy steel

Interactions amongst segregants at the grain boundaries of a low alloy steel have been studied using the technique of Auger electron spectroscopy in the temperature range of 750–900 K. Segregation isotherms delineate three kinetically distinct regimes. The first of these is characterized by rapid cosegregation of Cr and N with desegregation of C followed by segregation of V which occurs at relatively higher temperatures. The second stage involves rapid segregation of P which initially attains a maximum coverage and then subsequently decreases with time. The third regime noted at higher temperatures shows slow segregation of S, Sn and Sb. This regime, however, exhibits high sensitivity of site competition to temperature.     

Distribution of penicillin in the cornea, tears and aqueous humour at various times following a single intravenous injection

Bioassays performed by the disc diffusion technique on samples of blood, tears, aqueous humour and cornea from 30 rabbits killed 4 to 24 hours following a single intravenous injection of benzylpenicillin (40 mg/kg) showed that the penicillin content of these fluids and tissues progressively decreased with time. However, even after 24 hours the agent could be detected in the samples. The peripheral and central cornea contained similar amounts of penicillin up to 16 hours; thereafter, the peripheral cornea contained more of the agent.     

Dissolution of hydrogen from the gas in steel at room temperature

The purpose of this paper is to show that embrittlement of steel deformed in a hydrogen atmosphere is caused by hydrogen entering the crystal lattice. Tensile tests are made under pure compressed hydrogen gas. It is shown that the hydrogen penetrates steel before any fissures develop. The penetration depends on the time of exposure of fresh surface produced by straining but does not depend directly on the strain rate. The hydrogen distribution vs depth was measured. It agrees with a transient distribution calculated with an apparent solubility (1 cu cm per 100 g at 150 kp per sq cm) and an apparent diffusivity (1.3·10^?7 sq cm per sec).     

Single and complex effect of ammonia and hydrogen sulfide in the air on small laboratory animals (rats) under various environmental conditions. 1. Effect of ammonia

The maximum per-animal-position concentration of ammonia was studied under defined environmental conditions and with reference to basic stress on thermoregulation. The normal value of 30 ppm NH3, laid down in TGL 29084, was experimentally confirmed.     

Standard reference materials and data quality assurance in the biomedical analysis of trace elements

Accurate and precise analytical data of the concentrations of bio-analytes in bioclinical studies are of fundamental importance. Quality assurance procedures should always be performed to check the overall analytical work. This can be conveniently performed if appropriate standard reference materials with known concentrations of the analyte object of study are available. This paper underlines the key points related to the production and use of biological standard materials for trace element analysis. In particular, the present situation in the field of trace element determination in human biological fluids and the related problems are illustrated. The considerations given in this work may contribute to the preparation of the new biomarker standard materials.     

X射线荧光光谱在痕量和超轻元素分析中的应用评介

痕量元素和超轻元素分析是X射线荧光光谱(XRF)分析中最薄弱的两个方面,但也是XRF研究领域最活跃的部分。为了提高痕量和超轻元素的激发和探测性能,研究人员对仪器的设计和性能方面进行了改进,为了降低和扣除背景,对检出限的计算和样品粒度的减小等方面也进行了大量的研究。文章收集了XRF地质材料痕量元素分析文献223篇,超轻元素分析文献43篇,并从技术方法研究与应用、痕量多元素分析、痕量稀土元素分析、能量色散X射线荧光光谱仪在痕量元素分析中的应用和超轻元素分析等几个方面进行了评介。痕量和超轻元素分析方法的发展也为矿石多元素分析、海洋地质与矿产资源调查样品分析、大规模地球化学调查及全球地球化学填图样品分析配套方案中的痕量元素分析奠定了基础。全文引文266篇。     

6种南方酸性土壤重金属元素氯化钙可提取态标准物质研制

土壤重金属元素可提取态可更好地反映土壤中重金属的环境效应和生态风险,在土壤污染调查和研究工作中受到广泛关注。实验以CaCl₂溶液作为提取剂,研制了6种南方酸性土壤重金属CaCl₂可提取态标准物质。样品分别采自江苏、安徽、福建和贵州,经干燥、研磨、过筛、混匀等步骤制备而成,检验评估结果表明样品均匀性和稳定性良好。由11家实验室采用多种不同原理分析方法协作定值,认定值为多家实验室测试结果的算术平均值,定值指标(参数)包括CaCl₂溶液提取的Cd、As、Pb、Cr、Cu、Ni、Zn、V、Mn、Co、Mo、Tl、Sb、Be元素可提取态及pH值。该系列标准物质适用于土壤可提取态分析中仪器校准、分析方法确认和评价、测量过程质量控制、技术能力考核及分析结果仲裁等技术工作。