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Zusammenfassung Die Kinetik der Zersetzung der Äthylnitrolsäure in saurer Lösung zu Essigsäure und Stickoxydul wird an der Abnahme der Nitrolsäure und an der Bildung des Stickoxyduls gemessen. Zur Ermittlung der jeweiligen Konzentrationen der Nitrolsäure werden Proben des Reaktionsgemisches mit überschüssiger Natronlauge versetzt; der Gehalt dieser Lösungen an (rotgefärbtem) Natriumsalz der Nitrolsäure wird mit dem Stufenphotometer ermittelt. Es wird gefunden, daß unter den gegebenen Versuchsbedingungen die Äthylnitrolsäure nach dem Gesetz erster Ordnung zerfällt und daß diese Reaktion von Wasserstoffionen katalysiert wird.Mit 5 Abbildungen.Auszug aus der Dissertation vonA. Mirna, Techn. Hochschule Wien (1949). 相似文献
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Deanna Marcano Jeannette De Mndez Ana C. Ortiz Mirna Salinas 《Magnetic resonance in chemistry : MRC》1984,22(11):736-738
The 13C chemical shift data of several D-homoandrostanes with heteroatoms (N,O) in the 17a-position are reported. Heteroatom effects on the shieldings of the carbons of rings C and D are discussed. 相似文献
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Diacetylene-containing polyesters and polyurethanes were prepared by the reaction of m,m-butadiynylenedibenzyl alcohol with isophthaloyl chloride, sebacoyl chloride, hexamethylene diisocyanate and 2,4-tolylene diisocyanate. Their thermal behavior was studied by optical microscope and differential scanning calorimetry (DSC). The polyesters were crystalline. The polyurethane prepared from hexamethylene diisocyanate and polyphthalates crystallized on cooling from their melts. All turned a reddish brown color on heating at temperatures above 200°C, and prolonged heating led to a black resin, but thermal decomposition could not be avoided. Irradiation by γ-ray and UV light at room temperature deepened the color of the films, but the polymerization of the diacetylene groups was not appreciable. Simultaneous heating and irradiation was necessary to obtain transparent, amorphous, wine red colored films. 相似文献
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El Khatib M Elagawany M Jabeen F Todadze E Bol'shakov O Oliferenko A Khelashvili L el-Feky SA Asiri A Katritzky AR 《Organic & biomolecular chemistry》2012,10(25):4836-4838
Chemical ligation via O- to N-acyl transfer of O-acylated serine containing peptides affords serine containing native peptides via 8- and 11-membered cyclic transition states opening the door to a wide variety of potential applications to peptide elaboration. The feasibility of these traceless chemical ligations is feasible as supported by computation. 相似文献
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Ana C. R. Melo Edjane F. B. Silva Larissa C. L. F. Araujo Mirna F. Farias Antonio S. Araujo 《Journal of Thermal Analysis and Calorimetry》2011,106(3):691-696
In this study, were studied the degradation of pure sunflower oil and mixed with H-Beta zeolite. This zeolite was synthesized
by the hydrothermal method, followed by calcination and ion exchanged. The characterization of the zeolite was performed by
X-ray diffraction and nitrogen adsorption/desorption by the method of BET. The analysis showed that H-Beta zeolite presented
a good crystallinity and the template was completely removed from the catalyst. The thermal and catalytic degradation study
was carried out using the TG/DTG method in multiple heating rates of 5, 10, and 20 °C min−1. The isoconversion method proposed by Vyazovkin was applied to determine the kinetic parameters for degradation of the sunflower
oil. The activation energy for the degradation process of pure sunflower oil was 193 kJ mol−1, while for sunflower oil mixed with 20% of H-Beta zeolite was equivalent to 88 kJ mol−1. It was verified that for the degradation of 90% of the sunflower oil mixed with H-Beta, for a period of 1 h, a temperature
of 356 °C was required, whereas for the pure vegetable oil, this value was of 387 °C, at the same time period, showing that
the catalyst was effective for the degradation process of sunflower oil. 相似文献
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Mirna Ćurković Perica Ivana Šola Lidija Urbas Franci Smrekar Mladen Krajačić 《Journal of chromatography. A》2009,1216(13):2712-2716
A procedure based on BIA Separations CIM DEAE anion-exchange chromatography was developed to separate double-stranded (ds) RNA of hypovirus infecting phytopathogenic fungus Cryphonectria parasitica. Using a linear gradient of 25 mM 4-morpholinepropanesulfonic acid (MOPS), pH 7.0 as a binding buffer, and 25 mM MOPS, 1.5 M NaCl, 0.1 mM EDTA, 15% isopropanol (v/v), pH 7.0 as an elution buffer, hypoviral dsRNA was additionally purified from nucleic acid species present in preparations partially purified by standard CF-11 cellulose chromatography. Moreover, crude phenol/chloroform extracts of the fungal tissue were also applied to monolithic supports and CIM DEAE chromatograms revealed clear evidence for hypoviral presence without CF-11 chromatography, nucleic acid precipitation, and electrophoresis. 相似文献
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Jean M. J. Tronchet Guido Zosimo-Landolfo Fabienne Villedon-Denaide Mirna Balkadjian Daniel Cabrini Françoise Barbalat-Rey 《Journal of carbohydrate chemistry》2013,32(6):823-835
ABSTRACT Cyclopentylidene ketals, moderately more acid-labile than their isopropylidene analogs, offer an alternative to the latter blocking groups. They have been shown to resist a large variety of reaction conditions commonly encountered in carbohydrate chemistry. 相似文献
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Tanya L. Díaz-Ortiz Mirna Rivera-Claudio Carlos R. Cabrera-Martínez Rolando J. Tremont 《Applied Surface Science》2008,254(6):1587-1592
Gold surfaces have been modified by self-assembled techniques. Here the adsorption time of diasteroisomers (1R, 3S)-1-ferrocenyl-3-methyl-4,4-diphenyl-2,5-dioxacyclopentane and (1S, 3S)-1-ferrocenyl-3-methyl-4,4-diphenyl-2,5-dioxacyclopentane (Scheme 1, 3a and 3b) at a Au surface in ethanol solution was controlled. This study was followed by electrochemical impedance spectroscopy (EIS) and X-ray photoelectron spectroscopy (XPS) analysis. The method used for the surface modification was the control of exposure time of a Au surface in the modifier/ethanol solution. It was demonstrated by EIS and XPS that the Au surface was modified with mixture of compounds 3a + 3b, avoiding the electron transference in the interface. It was also observed that the organometallic molecule indeed had been adsorbed on the Au surface. In addition, evidence seems to conclude that the molecule-Au interaction is through the electrons of cyclopentadienyl moiety, where the oxygen atoms are near the air-molecule interface and the iron atom is near the Au surface. This type of interaction of the ferrocene derivatives with gold surfaces has not been reported by any other author. 相似文献