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101.
Monoclonal antibodies against zearalenone (ZEA) were raised in mice according to the hybridoma technology and applied in different immunochemical techniques. More specifically, three formats based on the competitive direct enzyme immunoassay principle were developed: an enzyme-linked immunosorbent assay (ELISA), a flow-through gel-based immunoassay column and a flow-through membrane-based immunoassay. In ELISA, the 50% inhibitory concentration (IC50) was 0.8 ng/mL, and the limit of detection for ZEA standard solutions was 0.1 ng/mL. The antibodies showed a high ZEA (100%) and α-zearalenol (α-ZOL) (69%) recognition, while cross-reactivities with α-zearalanol, zearalanone, β-zearalenol and β- zearalanol were 42%, 22%, <1% and <1%, respectively. For standard solutions, a cut-off level at 10 ng/mL could be established for the gel- and membrane-based enzyme immunoassays. Assay time of both non-instrumental tests was 25 min for 10 samples. By including a simple sample extraction procedure, the methods were applied to wheat with IC50s in ELISA of 80 and 120 μg/kg (dilution up to 5% and 15% (v/v) of wheat matrix, respectively). The cut-off level of the gel- and membrane-based immunoassays was established at 100 μg/kg. Potentials and limitations of the developed methods were compared. The possible application for multi-mycotoxin analysis of the ELISA method based on a single monoclonal antibody was investigated. Therefore, principal component analysis and partial least squares regression data modelling were used to separate the immunoassay responses of two cross-reactants (ZEA and α-ZOL).   相似文献   
102.
The μ-(oxo)bis[phthalocyaninato] aluminum(III) (AlPc)(2)O films, with the crystallites oriented preferably in one direction, were obtained via chemical transformation of chloroaluminum(III) phthalocyanine AlClPc film upon its annealing in magnetic field. A comparative analysis of the influence of postdeposition annealing without and under applied magnetic field of 1 T on composition and morphology of AlClPc films has been carried out. The chemical transformation of AlClPc to (AlPc)(2)O on the substrate surface is studied by the methods of UV-vis and infrared spectroscopies, Raman, x-ray photoelectron spectroscopy as well as atomic force microscopy. Two interesting effects were observed upon heating the AlClPc films in magnetic field of 1 T. First, the temperature of the chemical transformation of AlClPc to (AlPc)(2)O decreased from 300 °C to 200 °C when magnetic field was applied during postdeposition annealing. Second, the formation of (AlPc)(2)O films with elongated crystallites with a preferential orientation was observed. The heating of (AlPc)(2)O films in a magnetic field at the same conditions did not demonstrate any effect on the structure and morphology of these films.  相似文献   
103.
104.
The novel germanium-containing alkylidene complexes of molybdenum R3Ge-CHMo(NAr)(OCMe2CF3)2 (Ar = 2,6-i-Pr2C6H3; R = Me, Ph) have been prepared by the reaction of organogermanium vinyl reagents R3 GeCHCH2 with known alkylidene compounds Alkyl-CHMo(NAr)(OCMe2CF3)2 (Alkyl = But, PhMe2C). The titled compounds were isolated as crystalline solids and characterized by elemental analysis, 1H NMR, 13C NMR spectroscopy and X-ray diffraction studies. The geometry of the Mo atoms in the compounds can be described as a distorted tetrahedron.  相似文献   
105.
New tungsten carbyne complexes (ButO)3WC—SiPh3, [(ButO)3WC]2SiPh2, [(ButO)3WC]2GePh2, and [(ButO)3WC]2SnPh2 were prepared by the reactions of (But)6W2 with Ph3SiCC—Pr or Ph2E(CC—Pr)2 (E = Si, Ge, Sn) in individual crystalline form in 48—80% yields. The structures of both the (ButO)3WC—GePh3 and (ButO)3WC—SnPh3 compounds synthesized earlier and the new complexes were established by X-ray diffraction analysis.  相似文献   
106.
The retention of paracetamol, propyphenazone, caffeine, phenobarbital, and codeine phosphate, which are the components of the new medicine Pentalgin, was studied by reversed-phase high-performance liquid chromatography on a column (150 × 3.9 mm) filled with the Symmetry C18 sorbent (5.0 μm) in the gradient elution mode and on a column (150 × 3.9 mm) filled with the Nova-Pak CN HP sorbent (4.0 μm) as a function of the profile and composition of the gradient and as a function of the concentrations of acetonitrile and KH2PO4 and the pH of the mobile phase, respectively, with detection at 212 nm. The optimum composition of the mobile phase was selected. The time of separation was 16 and 11 min for the gradient and isocratic elution modes, respectively. The procedures were used for the analysis of a preproduction sample of the tablets. The procedures provide accurate and reproducible results of analysis; however, the isocratic version is preferable for mass production control as a technically simpler technique.  相似文献   
107.
Reaction of potassium (or sodium) triethoxysilanolate with AlBr3 in benzene in a 3 : 1 or 4 : 1 ratio yields, respectively, tris(triethoxysiloxy)aluminum Al[OSi(OEt)3 3 or potassium (or sodium) tetrakis(triethoxysiloxy)aluminate M{Al[OSi(OEt)3]4} (M = K, Na). Single-stage thermolysis of tris(triethoxysiloxy)aluminum (200°C) and potassium tetrakis(triethoxysiloxy)aluminate (300°C), followed by annealing of the solid residues at 1000-1250°C, yields ceramic materials, which were examined by X-ray diffraction. The crystalline phase obtained from tris(triethoxysiloxy)aluminum is aluminum metasilicate Al6Si2O13 (mullite), and the product obtained from potassium tetrakis(triethoxysiloxy)aluminate is a mixture of aluminum orthosilicate Al2SiO5 (kyanite) and feldspar aluminosilicate KAlSi3O8 (microcline).  相似文献   
108.
In inelastic collisions of protons with photoemulsion nuclei at 4·5 GeV/c, data have been obtained on multiplicity of shower particles, energy spectrum of fast secondary protons with (2·5±0·1) GeV average energy, and energy spectrum of produced charged pions with (640±±50) MeV average energy. The multiplicity, angular distributions, and energy of particles arising from splitting target-nuclei are also determined: the proton spectrum is approximated by the power dependenceE - with=1·4±0·1. The distribution of protons and-mesons over rapiditiesy=0·5 In[(E+p)/(Ep)] have been obtained. The average multiplicity for secondary particles coincide with the predicted values given by the cascade-evaporation model.Dedicated to the 25th anniversary of the Joint Institute for Nuclear Research.The authors would like to express their gratitude to the synchrophasotron group of JINR and to the group of S. J. Ljubomilov for the assistance in the experiment, to V. S. Barashenkov and V. V. Ivanov for the assistance in the cascade-evaporation model calculations, and also to the laboratories which took part in the scanning and measurement.  相似文献   
109.
Experimental evidence on the production, structure, and physiochemical properties of aluminum, zirconium, and titanium oxides modified with halides, sulfates, and boron and tungsten oxides. Information on the application of anion-modified metal oxides as catalysts in the production of ecologically pure components of motor fuels, with decreased contents of aromatic hydrocarbons and sulfur compounds. Therewith, along with traditional hydrocarbon oligomerization, isomerization, alkylation reactions, actual arene hydroisomerization processes and production of diesel fuels from vegetable materials are considered.  相似文献   
110.
New trinuclear organosilicon, organogermanium, and organotin-containing tungsten carbene complexes Ph2E[CH=WCl2(OBut)2]2 (E = Si, Ge, or Sn) were synthesized by the reaction of the trinuclear carbyne complexes Ph2E[C≡W(OBut)3]2 with HCl. The tin-containing carbene complex is thermally unstable and was identified in solution by 1H and 13C NMR spectroscopy. The silicon-and germanium-tungsten carbene complexes were isolated in high yields as individual crystals and were characterized by elemental analysis, IR spectroscopy, and 1H and 13C NMR spectroscopy. The structure of the silicon-containing complex Ph2Si[CH=WCl2(OBut)2]2 was established by X-ray diffraction. Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 11, pp. 2424–2427, November, 2005.  相似文献   
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