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401.
I. A. Novakov V. V. Korolkov A. I. Pavlyuchko L. A. Gribov 《Journal of Structural Chemistry》2005,46(1):159-163
The structure of the dimer associates of aniline and n-propylamine with dimethylsulfoxide, isobutyronitrile, and N-methylpiperidone was investigated by ab initio calculations. Stable configurations of the complexes and their structural and energy characteristics have been determined. The effects of the nature of the solvent and the structure of the associate on the properties of the NH2 group are examined. 相似文献
402.
Lou X van den Hout KP van Houtem MH van Dongen JL Vekemans JA Meijer EW 《Journal of mass spectrometry : JMS》2006,41(5):659-669
Four C3-symmetrical tris(dipeptide) disks and their precursors were characterized using matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI TOF MS). The C3-symmetrical disks were based on a benzene-1,3,5-triscarboxamide core extended by oligopeptides with trialkoxyanilide tails. The results indicate that MALDI TOF MS is a powerful and straightforward analytical technique for characterizing C3-symmetrical disks and their precursors. Clear (pseudo)-molecular ion peaks could readily be identified. It is remarkable that strong radical ion signals were observed for all the compounds, including the anilines that were expected to be protonated prior to laser irradiation using acidic MALDI matrixes. Possible mechanisms for radical ion formation were investigated with the employment of radical scavengers, with various matrixes and with direct laser desorption/ionization (LDI). Most likely the radicals are formed by losing one electron from the aniline nitrogen and stabilized by conjugation through the phenyl ring. It appears that direct photo/thermal ionization of analytes is an important route for the radical ion formation of the compounds with trialkoxy aniline/anilide groups. 相似文献
403.
The methods for preparing the H2O2 generating air (oxygen) electrode and the composite electrode of photocatalyst-TiO2/C loading on the surface of the air (oxygen) electrode were introduced.In the case of the composite electrode,the current efficiency of electro-generated H2O2 is higher than 80%(J≤15mA/cm^2).The degradation of aniline was used as an example to measure the influence of the composite electrode and compared with the system in which the air (oxygen) electrode and the photocatalyst-TiO2 were sqparated.The results confirmed that the composite electrode played an active role on accelerating the degradation rate of aniline.According to the measurement of the polarization curves of composite electrode and TiO2 photo anode,and of the adsorbing amount of aniline on the surface of the composite electrode,the principle of descending the recombination reta of photo-generated electron and hole and of enhancing the oxidation rate of organic molecule was described.The mechanism about the degradation of aniline was also discussed. 相似文献
404.
I. A. Novakov V. V. Korolkov A. I. Pavlyuchko B. S. Orlinson L. A. Gribov 《Journal of Structural Chemistry》2004,45(4):563-569
An ab initio (6-31G**) study of binary associates of aniline and n-propylamine with nitrobenzene and m-cresol has been carried out. The structures corresponding to the total energy minimum of the system have been found for the associates, and their geometrical and energy characteristics have been determined. Basic types of intermolecular interactions have been established, and their effects on the reactivity of the amino group have been investigated.Original Russian Text Copyright © 2004 by I. A. Novakov, V. V. Korolkov, A. I. Pavlyuchko, B. S. Orlinson, and L. A. GribovTranslated from Zhurnal Strukturnoi Khimii, Vol. 45, No. 4, pp. 595–601, July–August, 2004.This revised version was published online in April 2005 with a corrected cover date. 相似文献
405.
Gataullin R. R. Nasyrov M. F. D"yachenko D. I. Fatykhov A. A. Shitikova O. V. Spirikhin L. V. Abdrakhmanov I. B. 《Russian Chemical Bulletin》2002,51(1):124-127
Treatment of the ozonization products from N-acetyl- or 2-methyl-N-trifluoroacetyl-6-(cyclopent-1-enyl)anilines with NaBH4 gives 6-methyl-2-tetrahydropyranylaniline. When treated with Me2S, the ozonization products yield the corresponding oxoaldehyde dimethyl acetals. The oxidation of N-acetyl-2-(cyclopent-1-enyl)- or -(cyclohex-1-enyl)anilines with H2O2 in HCOOH affords -(2-acetamidophenyl)-5-oxopentanoic or -6-oxohexanoic acid, respectively. The reaction of N-acetyl-2-(cyclopent-1-enyl)aniline with H2O2 in the presence of Na2WO4 and H3PO4 gives 3,1-benzooxazine in high yield. 相似文献
406.
2-(Methylthio)aniline-modified Amberlite XAD-2 has been synthesized by coupling it through a NNNH group. The resulting chelating resin, characterized by elemental analysis, thermogravimetric analysis and infrared spectra, was used to preconcentrate Cd, Hg, Ni, Co, Cu and Zn ions. Several parameters, such as the distribution coefficient and sorption capacity of the chelating resin, pH and flow rates of uptake and stripping, and volume of sample and eluent, were evaluated. The effect of electrolytes and cations on the preconcentration was also investigated. The recoveries were >96%. The procedure was validated by standard addition and analysis of a standard river sediment material (GBW 08301, China). The developed method was utilized for preconcentration and determination of Cd, Hg, Ni, Co, Cu and Zn in tap water and river water samples by flame atomic absorption spectrometry with satisfactory results. The 3σ detection limit and 10σ quantification limit for Cd, Hg, Ni, Co, Cu and Zn were found to be 0.022, 0.028, 0.033, 0.045, 0.041, 0.064 μg l−1 and 0.041, 0.043, 0.052, 0.064, 0.058, 0.083 μg l−1, respectively. 相似文献
407.
Dodonov V. A. Zaburdaeva E. A. Stepovik L. P. Cherkasov V. K. 《Russian Chemical Bulletin》2003,52(4):910-915
The tri-tert-butoxyaluminum—tert-butyl hydroperoxide system generates molecular oxygen in the electron-excited singlet state (1O2), which oxidizes diphenylamine, N-ethylaniline, aniline, and 2,6-diisopropylaniline to form nitroxyl radicals. The latters were identified by ESR at 240—293 K. Oxidation proceeds via the intermediate formation of nitrogen-containing N-peroxide compounds. 相似文献
408.
Sungsik Baek Jason J. Ree Moonhor Ree 《Journal of polymer science. Part A, Polymer chemistry》2002,40(8):983-994
Poly(o‐aminophenethyl alcohol) and its copolymers containing the aniline unit were synthesized in aqueous hydrochloric acid medium by chemical oxidative polymerization. The chemical composition of these novel polymers was determined spectroscopically, and their viscosities were measured. These polymers exhibit good solubility in organic solvents that is attributed mainly to the polar hydroxyethyl side groups. Their structures (chain conformation and morphological structure) and properties (conductivity, electrochemical characteristics, glass transition, and degradation behavior) were characterized and then interpreted on the basis of the chemical composition along with the electronic and steric hindrance effects associated with the hydroxyethyl side group. Overall, the side group has a significant effect on the polymerization and influences the structure, chain conformation, and properties of the resultant polymer. The poly(aniline‐co‐o‐aminophenethyl alcohol)s containing 20–40 mol % o‐aminophenethyl alcohol units are potential conducting materials for microelectronic and electromagnetic shielding applications because they are easier to process than polyaniline but retain its beneficial properties. These polymers can also be used as a functional conducting polymer intermediate owing to the reactivity of the side group. © 2002 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 40: 983–994, 2002 相似文献
409.
R. R. Gataullin T. V. Kazhanova A. A. Fatykhov L. V. Spirikhin I. B. Abdrakhmanov 《Russian Chemical Bulletin》1990,49(1):174-176
ortho—para-Migration of the cyclopentenyl fragment in 2-(cyclopent-1′-enyl)aniline or 2-(cyclopent-1′-enyl)-6-methylaniline hydrochloride
at 200 °C gives 4-cyclopentylaniline or 4-cyclopentyl-2-methylaniline.
Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 1, pp. 171–173, January, 2000. 相似文献
410.
On-line preconcentration on a short C18 column, prior to HPLC with UV and electrochemical detection, has been used for determination of some phenylurea herbicides and their possible degradation products, substituted anilines, in water samples. With electrochemical detection the detection limit at a signal-to-noise ratio of 3 was 5 ppt for 4-chloroaniline and 4-bromoaniline and 7 ppt for 3,4-dichloroaniline; with UV detection the detection limit was ca 300 ppt for all analytes. 相似文献