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Abstract  

A method for determination of carbon content in natural silicate crystals has been elaborated using the12C(d,n)13N reaction. Etching of crystal surfaces by acid solutions is proposed to remove the pollutant surface layers. Carbon contents varying from 8 to 100 ppm were measured for olivine, orthopyroxene and gamet crystals.

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The paper analyzed the changes of beetle assemblages in the litter layer of eutrophic pine forests in the zone polluted by a nitrogen fertilizer plant Joint Stock Company “Achema” (Lithuania). We hypothesized that abundance, diversity and life traits of beetle assemblages depend on the distance from the pollution source. The samples of the litter layer were taken from pine stands at the distances of 3, 5, 10 and 20 km from the plant. The PCA and GLM analyses were used to reduce the number of variables to the main environmental gradient and assess the influence of environmental factors on beetle abundance, number of species, and life traits. The dependence of species number, abundance and the presence of forest and dendrophagous species on the distance from the plant was detected. A significant impact of organic carbon content, nitrogen emission and moss cover on other life traits of beetles was disclosed. The abundance of moss fraction in the litter layer was positively correlated with increasing distance from the plant. The ability to tolerate polluted sites by three species: Atheta fungi, Micrambe abietis and Brassicogethes aeneus, and intolerance of pollution by eight species: Bryaxis puncticollis, Quedius limbatus, Cyphon pubescens, Cephenium majus, Cyphon padi, Cyphon variabilis, Gabrius appendiculatus and Philonthus cognatus, were detected by IndVal analysis. The distribution of litter species was affected by the distance from the plant and by the richness of moss cover.

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Abstract  

Surface treatment on non-ferrous metals are proposed in order to minimize or determine quantitatively the interference of gaseous contamination. These proposals result from a large number of determinations of superficial contamination on several materials using microanalysis by nuclear reactions. This work is included in a larger program which aims the certification of standard materials in their oxygen, nitrogen and carbon contents.

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1 with low carbon content of 0.23 wt% and the sample S cp by co-precipitation method showed high and similar BET surface area (see Table 1 ), which was comparable with that of the catalyst prepared by controlled degradation method [ 14 ]. For the

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Journal of Thermal Analysis and Calorimetry
Authors: Xue-Gang Chen, Shuang-Shuang Lv, Ping-Ping Zhang, Lu Zhang, and Ying Ye

silica content of RHA increases with ashing temperature. For example in air atmosphere, the silica content of WRHA increases from 29.7% at 300 °C to 94.1% at 600 °C and 96.3% at 750 °C. On the contrast, the carbon content of WRHA decreases with ashing

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