中国正常成年人体内的钙含量

用火焰原子吸收光谱法测定了１００例中国正常成年人体内２０个器官组织中的钙含量。结果表明,我国男性成年人体内总Ｃａ含量仅为ＩＣＲＰ参考人的６０％,各器官组织中的Ｃａ浓度也皆低于ＩＣＲＰ参考人及亚洲一些国家的数值。初步分析认为,我国正常成年人体内的缺钙问题,主要与我国食品中Ｃａ的摄入量不足有关。     

锦灯笼中无机元素含量测定

采用ＩＣＰ－ＡＥＳ法检测了要笼果实及其干燥宿萼中无机元素含量。结果表明,锦灯笼含有丰富的对人体有益的无机元素,具较高的营养价值。     

ICP—AES法测定镍基合金中合金元素含量

ＩＣＰ ＡＥＳ法灵敏度高 ,线性范围宽 ,并同时测定多种元素 ,已成为现代分析测试技术中一个重要的检测手段 ,广泛地应用在各个领域。由于核电用材镍基合金焊丝及焊带是以镍作为基体 ,硅、锰、铬、铁等元素含量较高 ,而钛、铝的含量却很低 ,其基体较复杂 ,各元素含量相差又较悬殊 ,所以给分析工作带来困难。本文采用ＰＳ 6型ＩＣＰ多道真空光谱仪 ,通过对镍基合金试样的溶解方法、等离子体发射光谱仪的工作参数、共存元素的干扰、离峰分析校正等进行了研究 ,从而制定了相应准确有效的方法 ,解决了生产检测的困难 ,结果满意[1] 。1　试验部分…     

电热蒸发进样电感耦合等离子体原子发射光谱（ETV－ICP－AES）联用技术研究

本文采用国产部件组装了一套ＥＴＶ－ＩＣＰ－ＡＥＳ仪器体系，对装置的连接及操作参数进行优化。深入系统地考察了分析物的蒸发过程和传输过程，提出了难熔元素的蒸发和传输机理。研究了ＥＴＶ－ＩＣＰ－ＡＥＳ中基体效应，提出了以聚四氟乙烯为氟化剂，氟化辅助ＥＴＶ－ＩＣＰ－ＡＥＳ测定难熔元素的新方法，应用于环境和生物标样中痕量元素分析，获得满意结果。     

氟化电热蒸发／电感耦合等离子体原子发射光谱中的基体效应研究

本文系统研究了氟化电热蒸发／电感耦合等离子体原子发射光谱（ＥＴＶ－ＩＣＰ－ＡＥＳ）测定难熔元素的基体效应。与常规气动雾化（ＰＮ）－ＩＣＰ－ＡＥＳ中的基体效应比较，氟化ＥＴＶ－ＩＣＰ－ＡＥＳ中的基体效应更小。对难熔基体元素，由于基体和待测元素与氟化剂之间的竞争反应，随着基体浓度的增加，待测元素谱线强度降低；对常见基体元素，由于热循环中基体与待测元素之间的选择挥发，对待测元素的蒸发和传输过程无明显影响     

癌症病人头发中无机元素含量变化初探

采用ＩＣＰ－ＡＥＳ法测定了肺癌、肝癌、胃癌患者头发中２４种无机元素的含量,与对照组比较,探讨对癌症实验诊断有意义的指标。结果表明：肺癌、肝癌、胃癌患者头发中Ａｌ、Ｃｕ、Ｃｏ、Ｎｉ、Ｓｒ、Ｚｎ、Ｍｎ、Ｍｏ等元素含量与对照组存在显著差异（Ｐ〈０．０５）。因此采用多元素谱作为上述癌症辅助诊断指标相对于采用单元素值或元素比值作为诊断标准更具参考价值。     

激光烧蚀－电感耦合等离子体质谱法

激光烧蚀电感耦合等离子体质谱法已广泛应用于固体物质中无机元素的分析，描述了微ＬＡ—ＩＣＰＭＳ系统原理，讨论了操作参数的影响和定性及定量分析性能，并举例说明其应用。     

成人血清元素相关性及比值分析

用ＩＣＰ－ＭＳ法测定了７９例成人血清１４种元素水平,并进行了相关分析。结果提示,多种元素间存在显著正相关;分析了部分元素的比值,为相关研究提供了参考范围,且对元素比值的离散程度进行分析,为多元素关系研究提供了新的线索与依据。     

高山红景天中无机元素含量分析

采用原子荧光、火焰光度、ＩＣＰ－ＡＥＳ法测定了高山红景天中２８种无机元素，其含量各异，且因部位、年度、产地不同而异；所测元素加和量：须根〈根和根茎〈茎〈果皮〈种子〈叶，叶是富含部位；加和量均值，植株地上比地下部分高５７．６％，其中１０种人体必需微量元素含量和均值则高３．２倍；有害微量元素含量低于致毒量；长白山区高山红景天资源丰富，值得开发利用。     

人体由哪些元素组成

世间万物都是由各种元素的原子组成的,人也不例外。从化学元素周期表得知,至今人类一共发现了天然的和人工合成的元素有111种,其中目前已知天然存在的化学元素有92种。在人体内已经发现81种,这81种统称为生命元素。元素含量占人体质量万分之一以上的称为常量元素,又叫造体元素,     

中国正常人体内元素含量的检测研究

开展正常人体内元素含量的检测研究具有重要生物学意义，不仅可充实我国正常成年人脏器组织元素含量值的基础医学数据，为研究人体内微量元素与健康的关系提供科学依据、也为辐射防护领域内放射性核素的剂量估算提供重要参数。本文从以下五个方面进行了论述：（）体内元素含量检测研究的目的、意义及其概况；（2）元素含量检测的重要性及其历史沿革；（3）元素的检测方法及质量控制；（4）人体内脏器组织元素含量的数值；（5）与国外资料相比较。本文着重介绍了我国100例正常成年人20个脏器组织（包括胃、小肠、大肠、心、肝、脾、肺、肾、…     

A comparison of239+240Pu post-mortem measurements with estimates based on current ICRP models

Measurements of^239+240Pu in human tissues, from nuclear weapons testing, provide an invaluable source of data for verifying the uptake and distribution of radionuclides in the body. Measured concentrations of^239+240Pu in lung, tracheobronchial lymph nodes, liver and skeleton have been compared with concentrations calculated using estimated plutonium intakes, the ICRP Publication 66 Respiratory Tract Model and the ICRP Publication 67 biokinetic model for plutonium. Measurement data tend to fall between the concentrations estimated on the basis of Type M and Type S absorption parameters. This indicates that the models represent the movement of plutonium through the body reasonably well.     

Monte Carlo parametric modeling for predicting biomass calorific value

Due to the nonlinear relationship between the calorific value and the elemental concentration of biomass, methods such as linear regression, widely used in the literature to model this relationship, produce models that fail to provide well-grounded results. In this study, a novel approach, based on Monte Carlo parametric modeling, for calculating the calorific value of biomass from measurements provided by elemental analysis, is presented. Olive husk, a biomass source widely used in the Mediterranean basin, was the subject under investigation. A comprehensive analysis of the thermal properties of olive husk was conducted. The elemental analysis, as well as the calorific value, the moisture content the sampling and the preparation of the examined biomass were performed using the appropriate CEN standards and procedures. Based on the Monte Carlo parametric modeling, the parameters of an exponential model linking the elemental analysis and the calorific value of olive husk were estimated. This study is anticipated to provide further insight to the discussion on models for predicting the calorific value of biomass, by introducing a novel mathematical approach.     

Isothermal pyrolysis of cellulose untreated and treated with some flame-retardants

Linter cellulose, untreated and treated with boric acid, ammonium sulfamate, and guanidine sulfamate, was heated iosthermally in an imaging furnace thermal balance under a flow of helium gas to obtain kinetic parameters of the weight loss and changes in the elemental content and infrared (IR) spectra during pyrolysis. The weight, carbon, hydrogen, and oxygen losses of the untreated cellulose obey a zeroth-order reaction at an early stage and a first-order reaction at a later stage. The Arrhenius parameters for the weight and elemental losses are in agreement for both reactions. The activation energy and preexponential factor of the first-order weight loss are 185 kJ/mol and 2.0 × 10¹³ s^?1, respectively. The carbon, hydrogen, and oxygen losses of the samples treated with boric acid and guanidine sulfamate also obey a first-order reaction at a later stage of pyrolysis. The results of the elemental and IR spectral analyses suggest that the zeroth- and first-order reactions are caused mainly by the production of levoglucosan and that an initial rapid step, especially for the treated samples, is contributed by dehydration.     

French experience in the field of internal dosimetry assessment at a nuclear workplace: Methods and results on industrial uranium dioxide

The implementation of the new ICRP recommendations and the diversity of industrial exposure materials make it necessary to modify our approach of assessing internal dosimetry.This paper describes a methodology developed to assess different parameters such as (1) activity concentration and particle size distribution at the workplace; (2) physico-chemical characteristics of industrial dust handled, and (2) in vitro and in vivo, solubility in order to determine the absorption rate into blood. The determination of such specific parameters will lead to dose calculation in terms of committed effective Dose Per Unit of Intake (DPUI). Results obtained for an industrial uranium dioxide, UO₂, at a French nuclear facility are presented.     

Specific absorption parameters for uranium octoxide and dioxide applicable to the ICRP Publication 66 respiratory tract model

Literature data from in vivo chest measurements and urinary excretion rates of individuals exposed to U₃O₈ and UO₂ were used to compare the results predicted by different models with empirical observations in humans. As a result the use of the respiratory tract model proposed in ICRP Publication 66 with its default absorption parameters underestimates urinary excretion of inhaled U₃O₈ and UO₂. The new respiratory tract model also overpredicts the Fecal/Urine activity ratio, independently of the systemic model. For U₃O₈ and UO₂ the choice of systemic model has very little influence on the predicted urinary excretion of inhaled compounds. On the other way, the choice of the respiratory tract model does influence the predicted urinary excretion significantly. In this work specific absorption parameters for U₃O₈ and UO₂ were derived to be used in the respiratory tract model proposed in ICRP Publication 66. The predicted biokinetics of these compounds were compared with those derived for Type M and Type S compounds of uranium.     

Use of animal studies for assessing intakes of inhaled actinide-bearing dusts

This paper reviews the methodology used in the execution and interpretation of animal studies (mostly conducted at NRPB) designed to provide guidance on limits of intake and the effectiveness of chest monitoring for persons exposed to various uranium, plutonium, americium, and thorium bearing dusts. The lung retention and transportability characteristics of the actinides in humans have been predicted by combining the absorption rates into blood calculated from the animal studies with particle transport rates from the alveolar region of the human lung. This approach is compatible with the application of the new ICRP respiratory tract model.The results of the animal experiments demonstrate the diversity of the absorption rates for the different chemical forms of the actinides and their disparity from the default values proposed by ICRP for Type F, M, and S compounds in the absence of specific data. The predicted lung retention kinetics of the actinides in humans provide the basis for assessing the validity of chest monitoring; for this purpose the most recent ICRP values for doses per unit intake and deposition in the alveolar region of the lungs have been taken into account. The results show that for some dusts, the data can be interpreted with confidence, while for others the method is impracticable or has considerable uncertainty. Overall, the results support the ICRP recommendation that material specific information is to be preferred for setting limits on intake and interpreting monitoring data.The paper concludes with suggestions for further work.     

Absorption kinetics of uranium tri-n-butyl phosphate in the rat: Implications for occupational exposure

The absorption kinetics for uranium into blood after deposition as tri-n-butylphosphate (UTBP) in the rat lung were combined with human data on particle deposition and clearance from the ICRP Publication 66 respiratory tract model and information from the most recent ICRP biokinetic model for uranium to predict the consequences for exposure of workers. These predictions suggest that, (1) the biokinetics of UTBP are similar to those for a Type F compound as defined by ICRP, (2) the dose coefficient is essentially independent of the aerosol size and isotopic composition, (3) the mass of uranium equivalent to the ALI can vary by 13 fold depending upon the isotopic composition, (4) intakes of uranium as UTBP other than chronic intakes as highly enriched forms should be restricted on the basis of the chemical toxicity of uranium, (5) the assessment of intake by urine bioassay measurements should be interpreted with caution unless the exposure conditions are well defined and (6) severe kidney damage is unlikely at intakes corresponding to the ALI or daily limit.     

Pyrolysis of solid waste in a rotary kiln: influence of final pyrolysis temperature on the pyrolysis products

Temperature is one of the most important parameters in pyrolysis reaction. In present work, an externally heated laboratory-scale rotary-kiln pyrolyser was designed and developed. The influence of final pyrolysis temperature (FPT) on the pyrolytic products of solid wastes has been studied. Raising FPT caused increasing gas yield and decreasing semi-coke yield. The average heat value of the gas also changed with FPT. The content of aliphatic hydrocarbons in PE tar increased initially and then decreased with increasing FPT. Parallel to this, the content of aromatic ring changed conversely. FPT had obvious influence on the primary and elemental analysis data of the semi-cokes. The CO₂ reactivity of the semi-cokes also varied with the FPT. The kinetic parameters of the semi-cokes were different for the same material at the different FPT.