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1.
The nature of the luminescence of zinc sulfide in the spectral range (360), 380–420 nm (SAL) at 80K is analyzed. It is shown that the appearance of SAL radiation is accompanied by additional absorption in the region (350) 365–370 nm at 80K. The low-temperature spectra of sphalerite, exposed to different radiation and subjected to different treatment, are studied. The multiband luminescence of the isoelectronic sulfur impurity in ZnO deposits in the region 383–640 nm is discussed. It is concluded that SAL luminescence is attributable to the localization of excitons in ZnS on clusters, whose formation precedes the precipitation of the ZnO·S phase. The formation of oxygen clusters and deposits on dislocations in ZnS is studied.Translated from Izvestiya Vysshikh Uchebnykh Zavedenii, Fizika, No. 2, pp. 60–66, February, 1987.  相似文献   
2.
Oxidation of 2-methylnaphthalene with ozone   总被引:2,自引:0,他引:2  
In the oxidation of 2-methylnaphthalene with ozone in acetic acid, the oxidant reacts mainly at the double bonds of the substituted aromatic ring to give peroxy compounds. In the presence of cobalt diacetate and sodium bromide, oxidation of the 2-methyl group occurs with formation of 2-naphthoic acid. The major product in the oxidation of 2-methylnaphthalene with ozonated transition metal compounds is 2-methyl-1,4-naphthoquinone.__________Translated from Zhurnal Organicheskoi Khimii, Vol. 40, No. 12, 2004, pp. 1829–1830.Original Russian Text Copyright © 2004 by Mamchur, Galstyan.  相似文献   
3.
Oxidation of 2,4-dinitrotoluene to 2,4-dinitrobenzoic acid with an ozone-oxygen mixture in glacial acetic acid was studied.  相似文献   
4.
The reaction of (methanediyldibenzene-4,1-diyl)dimethanethiol, (oxydibenzene-4,1-diyl)dimethanethiol, biphenyl-4,4′-diyldimethanethiol with 1-(oxiran-2-ylmethyl)piperidine and N-(oxiran-2-ylmethyl)-N-ethylaniline afforded the corresponding sulfur-containing vicinal aminoalcohols resulting from the opening of the oxirane ring in keeping with Krasusky rule.  相似文献   
5.
6.
The kinetics and the mechanism of the liquid-phase oxidation of 2,4-dinitrotoluene with ozone in the presence of manganese(II) acetate have been investigated. The major products of 2,4-dinitrotoluene oxidation with ozone in acetic anhydride are 2,4-dinitrobenzyl acetate (65.8%) and 2,4-dinitrobenzylidene diacetate (18.8%). The effect of the manganese(II) acetate concentration on the selectivity of substrate oxidation at the methyl group is reported. A redox catalysis mechanism providing an explanation to experimental data is considered.  相似文献   
7.
In this contribution we report on the synthesis, characterization and application of water-soluble zinc(II) phthalocyanines, which are decorated with four or eight umbelliferone moieties for photodynamic therapy (PDT). These compounds are linked peripherally to zinc(II) phthalocyanine by a triethylene glycol linker attached to pyridines, leading to cationic pyridinium units, able to increase the water solubility of the system. Beside their photophysical properties they were analyzed concerning their cellular distribution in human hepatocyte carcinoma (HepG2) cells as well as their phototoxicity towards HepG2 cells, Gram-positive (S. aureus strain 3150/12 and B. subtilis strain DB104) and Gram-negative bacteria (E. coli strain UTI89 and E. coli strain Nissle 1917). At low light doses and concentrations, they exhibit superb antimicrobial activity against Gram-positive bacteria as well as anti-tumor activity against HepG2. They are even capable to inactivate Gram-negative bacteria, whereas the dark toxicity remains low. These unique water-soluble compounds can be regarded as all-in-one type photosensitizers with broad applications ranges in the future.  相似文献   
8.
Reaction of toluene with ozone in acetic anhydride was studied. The dependence of the direction, selectivity, and extent of oxidation on the reaction temperature, solvent nature, and catalyst composition was examined.  相似文献   
9.
The kinetics of acetamidotoluene oxidation in glacial acetic acid in the presence of cobalt acetate is reported. At 95°C and atmospheric pressure, acetamidotoluenes are oxidized by molecular oxygen very slowly: oxidation is complete in 10–12 h, and the major reaction products are acetamidobenzoic acids (27–36% yield). The introduction of ozone into the reactive gas increases the reaction rate by one order of magnitude. The main role of ozone is to generate the active form of the catalyst.  相似文献   
10.
If regularity in data takes the form of higher-order functions among groups of variables, models which are biased towards lower-order functions may easily mistake the data for noise. To distinguish whether this is the case, one must be able to quantify the contribution of different orders of dependence to the total information. Recent work in information theory attempts to do this through measures of multivariate mutual information (MMI) and information decomposition (ID). Despite substantial theoretical progress, practical issues related to tractability and learnability of higher-order functions are still largely unaddressed. In this work, we introduce a new approach to information decomposition—termed Neural Information Decomposition (NID)—which is both theoretically grounded, and can be efficiently estimated in practice using neural networks. We show on synthetic data that NID can learn to distinguish higher-order functions from noise, while many unsupervised probability models cannot. Additionally, we demonstrate the usefulness of this framework as a tool for exploring biological and artificial neural networks.  相似文献   
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