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71.
Cemil Aydoan Aslhan Gkaltun Adil Denizli Ziad El‐Rassi 《Journal of separation science》2019,42(5):962-979
In recent years, the use of organic polymer monolithic capillary columns in separation science has gained popularity due to the fact that they are easy to fabricate and do not require retaining frits. These materials have been applied in different fields including foods, proteomics, and pharmaceuticals. The interest in food analysis still needs to develop in order to increase the sensitivity towards micro/nano‐scale food applications for food samples of < 5 μg (e.g., foodomics). In this regard, polymer monolithic capillary columns offer great separation capability in the food analytical separation science. We review the most important applications in food analysis using polymer monolithic capillary columns. In addition, several examples of the use of capillary separation methods combined with mass spectrometry detection in food analysis are summarized. 相似文献
72.
Using scanning tunneling microscopy (STM) and density functional theory simulations, we have studied the diffusion of alkoxy species formed by the dissociation of alcohols on bridge-bonded oxygen (BBO) vacancies (BBO(V)'s) on TiO2(110). At elevated temperatures (>or=400 K) the sequential isothermal STM images show that mobile BBO(V)'s mediate the diffusion of alkoxy species by providing space for alkyl-group-bearing BBO atom to diffuse into. The experimental findings are further supported by simulations that find that BBO(V) diffusion is the rate limiting step in the overall diffusion mechanism. 相似文献
73.
74.
J. Málek R. A. Evarestov A. N. Ermoshkin B. Hejda K. Polák 《Czechoslovak Journal of Physics》1975,25(11):1201-1207
One-electron energy levels of NiF
6
4–
cluster, effective charges qNi and qF, parameters 10Dq,
crys
,,f
s
,f
andf
were calculated using four alternative models of population analysis. The influence of the size of basis set was also investigated. Based on comparison of results it was shown that all evaluated quantities are dependent on the manner of division of overlap charge made up by virtual 4s and 4p nickel orbitals. To remove this discrepancy it was suggested to assign the whole 4s and 4p population to ligands. In this case all calculated parameters are nearly independent of a model of population analysis and the size of basis set and their values correspond better to experimental data. 相似文献
75.
76.
H. H. Willard J. J. Thompson E. Kasper P. Slawik A. W. Middleton K. Seelkopf H. Taeger P. Schmidt F. Weyrauch A. Necke H. Müller A. J. Lindsey B. Park E. J. Lewis O. B. Winter Helen M. Robinson F. W. Lamb E. J. Miller C. E. Willoughby E. S. Wilkins E. O. Kraemer A. Jílek J. Kota 《Analytical and bioanalytical chemistry》1936,106(4-6):200-207
77.
Abdülhadi Baykal Nermin Kasapoğlu Yüksel Köseoğlu Ali Cemil Başaran Hüseyin Kavas Muhammet S. Toprak 《Central European Journal of Chemistry》2008,6(1):125-130
A series of Ni-doped cobalt ferrites NixCo1−xFe2O4 (x = 0.0, 0.4, 0.6, 0.8, and 1.0) were prepared using microwave-induced combustion. Nickel, cobalt, and ferric nitrates were
used as starting materials and glycine as fuel. The influence of Ni content on the lattice parameter, stretching vibrations,
and magnetization was studied. XRD, FTIR, and SEM were used for structure, composition, and morphology investigation. A porous
network structure was observed with average particle size 60–67 nm. All samples had a cubic spinel structure. The unit cell
parameter “a” decreases linearly with nickel concentration due to the smaller ionic radius of nickel. Magnetization measurements
showed that coercivity decreased as Ni content increased; it increased with decreasing temperature.
相似文献
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80.
Cejka C Pláteník J Guryca V Sirc J Michálek J Brůnová B Cejková J 《Photochemistry and photobiology》2007,83(3):652-657
Under normal conditions, the cornea absorbs the majority of UVB (ultraviolet B, 280-320 nm) rays, which is very important for the protection of the inner eye against their damaging effect. Our previous studies have shown that repeated irradiation of the rabbit cornea with UVB rays for 5 days (daily dose of 1.01 J cm(- 2)) caused photokeratitis accompanied by swelling (hydration) of the corneal stroma, thinning of the corneal epithelium and decrease in antioxidants. The purpose of this study was to examine the light absorption properties of such damaged rabbit cornea. Results of both spectrophotometry of the whole corneal buttons and corneal tissue dissolved in sodium hydroxide show that because of above mentioned disturbances, UVB-irradiated cornea absorbs more light throughout the whole measurable UV-VIS spectral range than the normal cornea. Increased corneal thickness (result of hydration), changes of corneal transparency (the cornea becomes grayish) and some increase in protein content all contribute to the increased light absorption of UVB irradiated corneas. We suggest that the UVB-irradiated cornea, although damaged and nearly without antioxidants, might actually through its higher UV absorbance protect the inner eye against further damage from UVB rays. 相似文献