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951.
Michal Korenko Marián Kucharík Jozef Vincenc Oboňa Dušan Janičkovič Rosa Córdoba José María De Teresa Blanka Kubíková 《Helvetica chimica acta》2008,91(7):1389-1399
The rapid‐solidification processing (by a cooling rate of 105–106 K/s) was used for the preparation of deeply undercooled cryolite/alumina (Na3AlF6/Al2O3) melts. We found a mass of nanotubes on the surface of these undercooled melts. The nanotubes were preferentially located on the defect places of the surface with the following approximate dimensions: base≈100×100 nm, length≈1000 nm. The solidified samples with the nanotubes on the surface were analyzed by scanning electron microscopy (SEM), energy‐dispersive X‐ray spectroscopy (EDX), X‐ray diffraction (XRD), and infrared spectroscopy (IR). 相似文献
952.
Zorica Bugarcěi? Slobodan Novokmet Zěeljko Seni? Zěivadin Bugarcěi? 《Monatshefte für Chemie / Chemical Monthly》2000,52(12):799-802
Carbonyl compounds of the type XPhCOR (R = H, Me, Ph; X = H, Me, Cl, Br) are prepared in high yields by reaction of the corresponding benzylic alcohols XPhCHOHR with KNa4 [Ag(HIO6)2]×12H2O in alkaline solution. This method allows the selective oxidation of benzylic alcohols in compounds containing other types of alcoholic functional groups. 相似文献
953.
954.
It is shown that a slab with a high dielectric constant and electrodes arranged in the form of narrow parallel equidistant strips may serve as a simple and effective generator of electromagnetic radiation for the very high frequency region. Its resonant properties may serve for accurate measurements of the dielectric constant in that frequency region. 相似文献
955.
Antibody-based methods for surfactant screening 总被引:1,自引:0,他引:1
M Fránek J Zeravík S A Eremin J Yakovleva M Badea A Danet C Nistor N Ocio J Emnéus 《Fresenius' Journal of Analytical Chemistry》2001,371(4):456-466
This brief overview summarises the immunoassay-based results obtained in the course of two years of the European INCO-Copernicus project BIOTOOLS. The project is aimed at simplifying the procedures for detection of surface active compounds (SAC) using, among others, antibody-based methods, i.e., microtiter plate-based enzyme-linked immunosorbent assays (ELISA), polarisation fluoro immunoassays (PFIA), and enzyme flow injection immunoassays (FIIA). Thirty-three rabbits were immunised with five different sulphophenyl moieties and three p-hydroxyphenyl moieties conjugated to protein immunogens to produce analytical antibodies against linear alkylbenzene sulphonates (LAS) and nonylphenol (NP). Although most of the antibodies exhibited binding reaction in indirect ELISA, only a few showed the required assay sensitivity. The best antibodies for LAS exhibited a 50% binding inhibition at IC50 19.8 microg L(-1) in indirect ELISA. Similar inhibition was observed for direct ELISA using peroxidase tracers. Antibodies against NP allowed the establishment of an indirect assay operating in the mg L(-1) range. A rapid and simple protocol for the screening of NP and LAS using homogeneous PFIA is described. The assay time for 10 samples was 7 minutes, thus allowing fast detection of the selected SAC at the mg L(-1) level. A generic competitive FIIA system, using a protein G column for separation of free and antibody-bound beta-galactosidase (beta-Gal) tracer, was developed for the screening of LAS, NP, and nonylphenol decaethoxylate (NPEO10). The FIIA had a sample throughput (STP) of 5-10 samples per hour, with limits of detection (LOD) for LAS, NP, and NPEO10 of 19.5, 52, and 2.4 microg L(-1), respectively. The developed FIIAs were applied to spiked rain and surface water. 相似文献
956.
E Mincsovics Gy Kátay P G Ott Zs Király-Véghely Á M Móricz E Tyihák 《Chromatographia》2005,62(13):s51-s56
The first results of the combination of BioArena and OPLC with flowing eluent wall technique (FEW) show an especially attractive solution of the detection of antimicrobial activity and compound isolation based on peak collection. Because of the different separation mechanisms applied for on-line FEW–OPLC isolation of red wine constituents and for further off-line OPLC investigation of fractions, the combined system yields high selectivity. 相似文献
957.
A. Lančok K. Závěta M. Popovici C. Savii M. Gich A. Roig E. Molins K. Barčová 《Hyperfine Interactions》2005,165(1-4):203-208
Magnetic aerogels with very low volume density of ~0.2 g/cm3 were prepared by sol-gel method and supercritical drying. The resulting materials were monolithic and displayed high surface area. By X-ray diffraction and Mössbauer spectroscopy the crystalline phase formed inside the mesopores of the SiO2 matrix was identified as a spinel iron oxide. Comparison of the magnetic measurements with Mössbauer spectra at various temperatures contributed to the elucidation of the magnetic state of this nanocomposite system with restricted magnetic interactions, in particular its transition to a superparamagnetic state. 相似文献
958.
Joseph Kürschák 《Mathematische Annalen》1887,30(4):578-581
Ohne Zusammenfassung 相似文献
959.
Let R
8 denote the 8-element bounded tower. G. Tardos has shown that C(R
8), the clone of all monotone functions on R
8, is not finitely generated. In this paper we show that the clone of all nonsurjective functions is finitely generated. 相似文献
960.