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51.
Mieczyslaw Altman 《Journal of Differential Equations》1978,28(3):406-436
A further development of the concept of contractor directions is presented. An application of the method of specialized contractor directions to local existence theorems for general nonlinear equations and to solutions of some partial differential equations is discussed. An implicit function theorem of the type investigated by Nash, Schwartz and Moser follows. 相似文献
52.
M. Busch J. D. Bukschnewski O. Wagner Th. Heinz Faust Theo Spängler J. F. Lemp H. J. Broderson C. F. van Duin C. W. Geiter F. L. Smith Mieczyslaw Proner Jean Piccard Fernand de Montmollin und Thomas Robert Jacobs 《Fresenius' Journal of Analytical Chemistry》1928,74(8):315-320
Ohne Zusammenfassung 相似文献
53.
Mieczyslaw Miel Arski 《无机化学与普通化学杂志》1971,386(3):345-352
By use of the transpiration method, the partial vapour pressures of the CuCl? KCl system were measured at 800°C as a function of composition of the system. The Rodebush-Dixon method has been applied for the determination of the total vapour pressure of the system. The average molecular weight obtained for copper(I) chloride indicate on the dimerized trimer structure (Cu3Cl3)2 in the vapour phase. An attempt to explain the mechanism of the dimerization is quoted. Basing on the Duhem-Margules equation and the thermodynamic stability of the system, it was deduced that except copper(I) chloride and potassium chloride, a compound of these two must exist in the vapour phase. The vapour pressures of the components in the pseudo-binary system are derived. 相似文献
54.
Iwona Gęca Mateusz Ochab Mieczyslaw Korolczuk 《International journal of environmental analytical chemistry》2016,96(13):1264-1275
For the first time, a solid lead electrode (PbE) was exploited for adsorptive stripping voltammetric determination of Ni(II) and Co(II) in the presence of nioxime as a complexing agent. The calibration graphs for Ni(II) and Co(II) were linear from 0.059 to 0.59 µg L?1 and from 0.029 to 0.29 µg L?1 (accumulation time 120 s), respectively. The analytical parameters such as the detection limit and separation of analytical signals obtained at the solid lead electrode were comparable with those obtained using a lead film electrode while better in comparison to those reported before for the bismuth film or solid bismuth electrodes. Co(II) could be determined in the presence of a large excess of Ni(II) and Zn(II). The proposed electrode was applied to determine Co(II) and Ni(II) traces in certified reference material and a natural water sample with satisfactory results. 相似文献
55.
Direct PTC methylation of 2-nitroanilines with dimethyl sulfate gave selectively N-monomethylated products. A variety of N-methyl-2-nitroanilines were prepared in this way. 相似文献
56.
An adsorptive stripping voltammetric procedure for the determination of cobalt in a complex matrices at an in situ plated lead film electrode was described. The procedure exploits the enhancement effect of a cobalt peak observed in the system Co(II)–nioxime–piperazine‐1,4‐bis(2‐ethanesulfonic acid)–cetyltrimethylammonium bromide. The calibration graph was linear from 5×10?10 to 2×10?8 mol L?1 and from 1×10?10 to 1×10?9 mol L?1 for the accumulation times 120 and 600 s, respectively. The detection limit (based on the 3 σ criterion) for Co(II) following accumulation time of 600 s was 1.1×10?11 mol L?1. The interference of high concentrations of foreign ions and surfactants was studied. 相似文献
57.
Jerzy Zak Mieczyslaw Lapkowski Stephane Guillerez Gerard Bidan 《Journal of Solid State Electrochemistry》2006,10(3):134-139
An existence of a new, stable oligomer state of the solid film is reported, which is produced under electrochemical conditions.
In this state, a formal charge exchanged in the redox process is about one-half of electron per oligomer molecule. The procedure,
which allows controlling precisely the amount of oligomer on the electrode surface, is proposed that together with the coulometric
evaluation of the electric charge provides the number of electrons involved in a redox process. This is demonstrated for a
case of α-monochloro-substituted regioregular sexi (3-octylthiophene) oligomer (6OTCl). The electrochemical results are discussed
together with UV–Vis–NIR spectroelectrochemical data obtained for both solution and solid phase that support the proposed
interpretation.
相似文献
Mieczyslaw LapkowskiEmail: |
58.
An adsorptive stripping voltammetric (AdSV) procedure for simultaneous determination of Ni(II) and Co(II) in the presence of nioxime as a complexing agent at an in situ plated lead film electrode was described. The Co(II) signal was enhanced by exploitation of the catalytic process in the presence of nitrite. Ni(II) and Co(II) signals are better separated than in the case of bismuth film electrodes. Calibration graphs for an accumulation time of 120 s are linear from 1 × 10−9 to 1 × 10−7 mol L−1 and from 1 × 10−10 to 5 × 10−9 mol L−1 for Ni(II) and Co(II), respectively. The proposed procedure was applied for Ni(II) and Co(II) determination in water certified reference materials. 相似文献
59.
Henryk Foks Danuta Pancechowska-Ksepko Mieczyslaw Janowiec Zofia Zwolska Ewa Augustynowicz-Kopec 《Phosphorus, sulfur, and silicon and the related elements》2013,188(11):2543-2548
2-chloro-3-cyanopyrazine was a substrate in the syntheses of some potentially tuberculostatic pyrazine derivatives. This compound, upon action of secondary amines, pyrazine derivatives 1-phenyl-, 1-piperonyl-, 1-(4-fluorophenyl)-, 1-(2-pyridil)-, and 1-benzylpiperazine, gave the corresponding nitriles ( 1a–e ). Compounds 1c , d , e were changed into the amidoximes ( 2c , d , e ) by hydroxylamine action. Derivatives 1a–e were transformed into the corresponding thioamides ( 3a–e ) when treated with ammonium polysulphide. Two of these, thioamides, 3a and 3b , in the cyclization reactions with ethylenediamine gave the imidazolines ( 4a , b ) with phenacyl bromide—the thiazole derivatives ( 5a , b ). The compounds obtained were tested in vitro for their tuberculostatic activity. The tuberculostatic activity of compound 5b was the highest: MIC 3.1–7.8 μ g/mL. 相似文献
60.
Mieczyslaw Mαjkosza Witold Danikiewicz Krzysztof Wojciechowski 《Phosphorus, sulfur, and silicon and the related elements》2013,188(1-4):457-475
Abstract Carbanions stabilized with sulfur containing substituents are versatile intermedi-ates in organic synthesis. The great value and importance of such carbanions is connected with specific properties of the sulfur atom which is capable to exist in a variety of valent states and to form many functional groups. These various sulfur-containing groups exert different carbanion stabilizing effects and can also serve as leaving groups in nucleophilic substitution or elimination reactions. Taking into account numerous types of sulfur containing functional groups and a variety of reactions they can promote, it is well understandable that reactions of sulfur-containing carbanions have been thoroughly studied and widely exploited in organic synthesis. The reactions of such carbanions with aliphatic electrophilic partners: alkylating agents, carbonyl compounds and Michael acceptors consist a major section of this field and were subject of numerous studies as well as many monographs.1 Contrary to that, not very much was known about reactions of such carbanions with electrophilic aromatic compounds. Actually, there are only few reports on nitroarylation of sulfur-containing carbanions via replacement of halogen orfho- or para- to the nitro group in halonitrocornpounds.2 There are also some reports on the alkylation of nitroarenes and heterocyclic compounds in the reaction with sulfonium3 and sulfoxonium4 ylides, dimethylsulfoxide carbanion,5 and dialkyl or alkyl aryl sulfones carbanions.6 相似文献