Search results for "composition"
showing 10 items of 2675 documents
Food and Environment: Trace Element Content of Hen Eggs from Different Housing Types
2013
AbstractEleven trace elements (Ba, Cu, Fe, Mn, Ni, Pb, Rb, Se, Sr, V, Zn) were quantitatively determined in hen egg samples collected from different poultry housing types (large-scale poultry farms, organic farms and domestic farms) over the territory of Latvia. Samples were wet digested and quantitatively analysed by total reflection X-ray fluorescence spectrometry (TXRF). The accuracy of analytical method was verified with analysis of certified reference material NCS ZC73017 (GSB-10)-Apple. The most variable range of concentrations and the highest content of elements were determined for hen egg samples derived from organic farms, while egg samples from domestic farms and poultry farms mos…
Comparison of the volatile oils ofHypericum scabrum L. andHypericum perforatum L. from Turkey
1997
The composition of the volatile oils obtained from the aerial parts of Hypericum scabrum L. and H. perforatum L. was analysed by GC and GC‐MS. While the oil of H. scabrum L. contained a-pinene (71.6%), b-caryophyllene (4.8%), myrcene (3.8%), cadalene (3.4%) and b-pinene (2.9%), the oil of H. perforatum L. contained a-pinene (61.7%), 3-carene (7.5%), b-caryophyllene (5.5%), myrcene (3.6%), cadalene (3.2%) and other components. Twenty-nine and 27 terpenoid compounds have been identified in the volatile oils of H. scabrum L. and H. perforatum L., respectively. #1997 by John Wiley & Sons, Ltd.
Null Space Based Image Recognition Using Incremental Eigendecomposition
2011
An incremental approach to the discriminative common vector (DCV) method for image recognition is considered. Discriminative projections are tackled in the particular context in which new training data becomes available and learned subspaces may need continuous updating. Starting from incremental eigendecomposition of scatter matrices, an efficient updating rule based on projections and orthogonalization is given. The corresponding algorithm has been empirically assessed and compared to its batch counterpart. The same good properties and performance results of the original method are kept but with a dramatic decrease in the computation needed.
FP749The effect of short daily home hemodialysis with low-flow, lactate-buffered dialysate on nutritional status and body composition
2019
Optimal Tree Decompositions Revisited: A Simpler Linear-Time FPT Algorithm
2020
In 1996, Bodlaender showed the celebrated result that an optimal tree decomposition of a graph of bounded treewidth can be found in linear time. The algorithm is based on an algorithm of Bodlaender and Kloks that computes an optimal tree decomposition given a non-optimal tree decomposition of bounded width. Both algorithms, in particular the second, are hardly accessible. We present the second algorithm in a much simpler way in this paper and refer to an extended version for the first. In our description of the second algorithm, we start by explaining how all tree decompositions of subtrees defined by the nodes of the given tree decomposition can be enumerated. We group tree decompositions …
The preparation of (14C) and [3H] labelled benzene oxide
1977
Benzene oxide -[U-14C] was prepared from benzene -(U-14C) by modifications of methods described for the inactive compound. Benzene oxide-[3.6–3H] was prepared by decomposition of 3.6-bis-trimethylsilyl-1,4-cyclohexadiene with tritiated water. bromination of the 1,4-cyclohexadiene-[3,6-3H] so obtained. epoxidation and dehydrobromination. With the latter method benzene oxide-[3,6–3H] can be prepared at a much lower cost and higher specific activity than benzene oxide-[U-14C].
Climatology of the average water-soluble volume fraction of atmospheric aerosol
2007
The average water-soluble volume fraction of atmospheric aerosol particles was inferred from measurements at three different locations across Central Europe. Together with a comprehensive literature review these data sets are classified into four aerosol types. The classified data are parameterized as a function of particle size using a logarithmic normal distribution function, which seems most appropriate to represent the hygroscopicity maximum in the accumulation size range. This parameterization can be used as a simplified input parameter for various model calculations. In addition, a summary on water-soluble volume fractions and hygroscopic growth factors is presented along with a short…
The dynamics of tropospheric aerosols
1966
After a brief review of the present knowledge of the Stratospheric sulfate layer, several possible mechanisms of formation are discussed in detail. A direct transport of low tropospheric particles into the stratosphere by convective clouds penetrating the tropopause is not very likely because these penetrations are not high enough and because of the chemical composition of the stratospheric particles. DOI: 10.1111/j.2153-3490.1966.tb00287.x
Size Matters More Than Chemistry for Cloud-Nucleating Ability of Aerosol Particles
2006
Size-resolved cloud condensation nuclei (CCN) spectra measured for various aerosol types at a non-urban site in Germany showed that CCN concentrations are mainly determined by the aerosol number size distribution. Distinct variations of CCN activation with particle chemical composition were observed but played a secondary role. When the temporal variation of chemical effects on CCN activation is neglected, variation in the size distribution alone explains 84 to 96% of the variation in CCN concentrations. Understanding that particles' ability to act as CCN is largely controlled by aerosol size rather than composition greatly facilitates the treatment of aerosol effects on cloud physics in re…
Regional variations in the chemical and helium–carbon isotope composition of geothermal fluids across Tunisia
2011
Abstract Tunisia has numerous thermo-mineral springs. Previous studies have shown that their chemical composition and occurrence are strongly influenced by the regional geology. However little work has been done so far to study the isotopic composition of volatiles associated with these geothermal manifestations. Here, we report on the results of an extensive survey of both natural hot springs and production wells across Tunisia, aimed at investigating the spatial distribution of thermal fluids' geochemical characteristics and He–C isotopic composition. The chemistry of the analyzed samples highlights the heterogeneity of the water mineralization processes in Tunisia, as a consequence of th…