ISSN:0021-1915    

DOI:10.1080/10256019308682860

出版商:Taylor & Francis Group    

年代:1993

数据来源: Taylor

摘要:

The authors review the recent literature, including their own approaches, of stable isotope techniques applied to determining environmental effects on the health of children. The techniques involve the measurement of variations in natural isotope abundances of some elements with environmental significance, the use of enriched stable isotopes forin vivoandin situtracer studies,in vitroisotope dilution techniques, and organ function tests using stable isotope-labelled compounds. These techniques are non-invasive and can be expected to contribute new insights into the behavior of different pollutants and their effect on children's health. Some of the techniques have been used in clinical research and diagnosis but their adaptation for investigations of clinically healthy children exposed to environmental pollution is desirable. Currently, as one of the specific aims of the Lepizig group of Human Exposure Research, the experience in biochemical and clinical isotope applications is being adapted to the environmental challenges in the heavily polluted industrial regions of Saxony.

ISSN:0021-1915    

DOI:10.1080/10256019308682861

出版商:Taylor & Francis Group    

年代:1993

数据来源: Taylor

摘要:

The influence of ventilation on overall fractionation effect of respiration (δIU) between the stable isotopic oxygen molecules16O2and16O18O is investigated by experiments performed on 6 healthy humans breathing air at rest.

ISSN:0021-1915    

DOI:10.1080/10256019308682862

出版商:Taylor & Francis Group    

年代:1993

数据来源: Taylor

摘要:

As investigated using the l,2-14C-labelled substance, rye and barley plants take up the plant growth regulator 2-chloroethylphosphonic acid (ethephon) by the leaves and roots proportionally to the time and to the given amounts. In 5 hours more than half of the applied ethephon was taken up by the leaves. Ethephon was detected only in the application area and in the leaf tip. When ethephon is taken up by the roots, there is a homogeneous distribution of ethephon in all parts of the plants.

ISSN:0021-1915    

DOI:10.1080/10256019308682863

出版商:Taylor & Francis Group    

年代:1993

数据来源: Taylor

摘要:

A method for sampling and measurement of krypton 85 in the atmosphere was developed based on the technique described by Stockburgeret al.[1, 2]. The air is pumped through charcoal cooled with liquid nitrogen. Krypton is obtained from the air sample by fractionated desorption followed by gaschromatographic separation with simultaneous determination of the krypton volume. The85Kr activity is measured in a proportional counter. The calibration was carried out with an accuracy of ±5.2% (significance level 95%).

ISSN:0021-1915    

DOI:10.1080/10256019308682864

出版商:Taylor & Francis Group    

年代:1993

数据来源: Taylor

摘要:

The tiny plutonium contamination of river sediments near a nuclear research center was measured with conventional radiochemical techniques. One could observe that up to some 10% of the emitted ar-activities were due to transuranium isotopes, the rest was due to uranium and thorium, resp. their decay products. The radioecological relevance of this observation is discussed.

ISSN:0021-1915    

DOI:10.1080/10256019308682865

出版商:Taylor & Francis Group    

年代:1993

数据来源: Taylor

摘要:

Results of tritium content measurements of groundwater from western Nile delta are presented and compared with the tritium content of the Nile according to a given model. These results indicate the dependence of the tritium concentration on the depth of well and geophysical structure of its location and also its proximity to irrigation channels.

ISSN:0021-1915    

DOI:10.1080/10256019308682866

出版商:Taylor & Francis Group    

年代:1993

数据来源: Taylor

摘要:

Estimation of the environmental hazard of waste deposits is obtained by column leaching experiments mainly. Comparison of results relies on rigid standardization.

ISSN:0021-1915    

DOI:10.1080/10256019308682867

出版商:Taylor & Francis Group    

年代:1993

数据来源: Taylor

摘要:

The solid-state reactions occurring during the moderation of (n, γ) produced hot80mBr were studied in K2OsBr6-K2OsCl6, K2ReBr6-K2ReCl6, and K2OsBr6-K2SnCl6mixed crystals. The formation of the main reaction products M80mBrBr5/2-, M80mBrCl5/2-(M = Re, Os), Os80mBrBr4Cl2-, and80mBr-is attributed to the following reaction channels: (1) primary retention or bond-preservation because of insufficient recoil energy, (2) billiard-ball reaction (substitution or replacement of ligands by recoil80mBr), (3) substitution as in (2) but formation of an additional ligand vacancy which is filled by an adjacent halide ion, and (4) capture of80mBr at interstitial vacancies. From the experimental results the contributions of these reaction channels were evaluated quantitatively.

ISSN:0021-1915    

DOI:10.1080/10256019308682868

出版商:Taylor & Francis Group    

年代:1993

数据来源: Taylor

摘要:

The formation of difficultly soluble dialkylphosphates, which — as it is well known — are also able to accumulate as crud by precipitation of Zr(IV) or Pu(IV) with dibutylphosphate, can offer problems at the recovery of nuclear fuels, during the purification of crystalline trialkylphosphate-complexes with some of the relevant isotopes, such as of U, Th, Ce and Zr. As those reactions can be already observed at ambient temperature and under exclusion of all radiolytic effects, and since explosive alkylnitrate is being formed during those degradations, conclusions are discussed concerning the technical procedure of the purex process to prevent any influences of possible damages to environment during the recovery.

ISSN:0021-1915    

DOI:10.1080/10256019308682869

出版商:Taylor & Francis Group    

年代:1993

数据来源: Taylor