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101.
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Magdalena E. Marzec Dorota Wojtysiak Katarzyna Potowicz Joanna Nowak 《Journal of mass spectrometry : JMS》2020,55(3)
This study is aimed to observe changes in fatty acid profiles by time of flight secondary ion mass spectrometry (ToF‐SIMS) in breast muscle tissues of broilers. Four different groups were identified. The source of fat in group I was soy oil (rich in linoleic acid, ω‐6), group II received linseed oil (ω‐3), and the third group was fed a mixture of the two mentioned oils. Broilers in the control group were fed with beef tallow, used in mass commercial production. The results reveal that the use of vegetable oils in animal nutrition determines the lipid profile of fatty acids. ToF‐SIMS measurements showed that the lipid profile of muscle fibers and intramuscular fat reflect the composition of fats used as feed additives. In both structures, the ratio of ω‐6/ω‐3 fatty acids, which is most favorable for human health, was found in the groups in which a mixture of vegetable oils and a supplement of linseed oil were used. 相似文献
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Elżbieta Lipiec Grzegorz Siara Katarzyna Bierla Laurent Ouerdane Joanna Szpunar 《Analytical and bioanalytical chemistry》2010,397(2):731-741
A method for the simultaneous determination of selenomethionine (SeMet), selenocysteine (SeCys), and selenite [Se(IV)] in
chicken eggs was developed. A sample preparation protocol including defatting, protein denaturation, and carbamidomethylation
was optimized in order to achieve complete protein digestion and to avoid SeCys losses. Quantification was carried out by
reversed-phase HPLC–inductively coupled plasma mass spectrometry (ICP MS) after quantitative isolation of the selenium-containing
fraction by size-exclusion liquid chromatography. The detection limits were 0.06, 0.003, and 0.01 μg g−1 (dry weight) for SeCys, Se(IV) and SeMet, respectively, and the precision was 5–10%. The end products of carbamidomethylation
of the different selenium species were identified for the first time by electrospray QTOF MS after custom-designed 2D HPLC
purification. Differences in selenium speciation in egg yolk and white were highlighted, the yolk containing more SeCys and
the white more SeMet. An insight into selenium bioaccessibility in eggs was obtained by digestion with simulated gastric and
gastrointestinal juices and size-exclusion HPLC-ICP MS. 相似文献
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Electrospun composite nanofibers for functional applications 总被引:1,自引:0,他引:1
In this article an outline of studies conducted to date utilizing the process of electrospinning is presented. This overview for the first time focuses on research of composite nanofiber synthesis and their applications. The phenomenon of bringing materials to the nanometer scale not only improves their properties, but also creates entirely new ones. The electrospinning technique is a simple and versatile method that offers a time and cost effective production of strategic combinations of polymer and composites nanofibers useful for numerous applications highlighted in this review. The future prospects of the field are also examined. 相似文献
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How Does Substitutional Doping Affect Visible Light Absorption in a Series of Homodisperse Ti11 Polyoxotitanate Nanoparticles? 下载免费PDF全文
Dr. Yang Chen Dr. Katarzyna N. Jarzembska Dr. Elżbieta Trzop Dr. Lei Zhang Prof. Philip Coppens 《Chemistry (Weinheim an der Bergstrasse, Germany)》2015,21(32):11538-11544
Homodisperse doped polyoxotitanate nanoclusters with formulae Ti11(MX)O14(OiPr)17 (M=Mn, Fe or Co; X=Cl, Br or I, OiPr=isopropoxide) display strongly dopant‐dependent properties. Spectroscopic solution and reflectance measurements backed up by density of states and time‐dependent DFT calculations based on the determined structures, show the prominent effect of FeX substitution by decreasing the HOMO–LUMO gap of the particles. The effect is attributed to the presence of an occupied Fe β orbital halfway up the bandgap, leading to long‐wavelength absorption with electron transfer to the titanium atoms of the cluster. Whereas the light absorption varies significantly with variation of the transition metal dopant, its dependency on the nature of the halogen atom or the change in dipole moment across the series is minor. 相似文献
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In this work we present a new approach for protection of the fiber in solid phase microextraction (SPME) from interfering charged particles present in the sample medium. It involves coating of commercial poly(dimethylsiloxane) extraction phase with polyelectrolyte layer composed of poly(diallyldimethylammonium chloride), and poly(sodium 4-styrenesulfonate). The modified fiber provides reproducible, convenient and fast extraction capabilities toward the model analyte, triclosan (TCS). A negatively charged polyelectrolyte coating prevents sorbing oxidic nanoparticles from both partitioning into the PDMS phase and aggregation at its surface. The results for the TCS/nanoparticle sample show that the polyelectrolyte layer-modified solid phase extracts just the free form of the organic compound and enables dynamic speciation analysis of the nanoparticulate target analyte complex. 相似文献