Untersuchungen über die Oxydation von Butylbenzol in flüssiger Phase in Gegenwart von Kobalt- und Mangansalzen der Pyridincarbonsäuren

Zusammenfassung Es wurde der Einfluß der Kobalt- und Mangansalze der -, - und -Pyridincarbonsäuren auf die Luftoxydation von Rutylbenzol in flüssiger Phase untersucht. Dabei wurde festgestellt, daß das Kobaltpicolinat, Manganisonicotinat und Kobaltisonicotinat den Oxydationsverlauf zur Bildung von Carbonylverbindungen und Säuren lenken. Das Manganpicolinat weist ein selektives Oxydationsvermögen auf, vorwiegend zur Bildung von Estern.

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Liquid phase oxidation of butyl-benzene in presence of Co and Mn pyridine carboxylates

The influence of Co- and Mn-salts of -, - and -pyridinecarboxylic acids, resp., on the oxidation of butylbenzene by air has been studied. It has been found that the Co salt of picolinic acid, Mn and Co isonicotinate direct the oxidation process in favour of carbonyl compounds and acids. With the Mn salt of picolinic acid, the oxidation mainly gives esters.

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Mit 5 Abbildungen     

Die Kristallstruktur von Perowskiten ANiIIMVIO6. I. Das Sr2[NiTe]O6

The structure of the perovskite compound Sr Ni^IITe^{VI (6)}O₆ (1:1 order in the octahedral sites) is described in detail. The obtained Ni? O distance (2.04 Å a_Te–O = 1.91 Å) together with that one within the corresponding tungsten perovskite (part II) will be analyzed quantitatively with respect to the connection between structure and ligand-field as well as EPR data. The comparison of this distance and the spectroscopic results of the tellurium perovskite with corresponding data of Ni^II-doped MgO however shows already now that an interpretation on the basis of an ionic model is impossible     

Transient analysis of a vibrating reed: Error analysis

The error analysis for the transient vibrating reed test is developed based on a linearized approximation. Tables are given for the efficient utilization of the equations in evaluating the accuracy range of test data.     

An automatic absorptiometric method for the determination of nitrate

A method has been developed for the determination of nitrate with the Technicon Autoanalyser in the range 2–10 p.p.m. The method depends on the reduction of nitrate to nitrite by hydrazine in alkaline solution, with copper as a catalyst. The nitrite produced diazotises sulphanilamide and the product is coupled with N-(1-naphthyl) ethylenediamine, to give a red dye, the absorbance of which is measured at 550 mμ. A relative standard deviation of 3–4% is obtained.     

Spreading of liquid drops over saturated porous layers

Spreading of small liquid drops over thin porous layers saturated with the same liquid is investigated from both theoretical and experimental points of view. A theory is presented that shows that spreading is governed by the same power law as in the case of spreading over a dry solid substrate. The Brinkman's equations are used to model the liquid flow inside the porous substrate. An equation of the drop spreading is deduced, which shows that both an effective lubrication and the liquid exchange between the drop and the porous substrates are equally important. The presence of these two phenomena removes the well-known singularity at the moving three-phase contact line. Matching of the drop profile in the vicinity of the three-phase contact line with the main spherical part of the drop gives the possibility to calculate the pre-exponential factor in the spreading law via permeability and effective viscosity of the liquid in the porous layer. Unfortunately, the latter dependency turns out to be very weak. Spreading of silicone oils over different microfiltration membranes is carried out. Radii of spreading on time experimental dependencies confirm the theory predictions. Experimentally found coefficients agree with theoretical estimations.     

Acid-base properties of 1-acyl-5-hydroxypyrazolidines in a hydrogen bond

In solutions, 1-acyl-5-hydroxypyrazolidines form only intermolecular hydrogen bonds in which the proton acceptor is the oxygen atom of the hydroxyl group. These compounds are similar to phenols with respect to the acidity in a hydrogen bond.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 7, pp. 936–939, July, 1989.     

Polysaccharides of subspecies of Cousinia

Institute of the Chemistry of Plant Substances, Uzbek SSR Academy of Sciences, Tashkent. Institute of Organic Chemistry, Kirghiz SSR Academy of Sciences, Frunze. Translated from Khimiya Prirodnykh Soedinenii, No. 5, pp. 750–751, September–October, 1988.     

Application of high-performance liquid chromatography of some antibiotics in clinical microbiology

During recent years high-performance liquid chromatography has become an excellent tool for the determination of antibiotics in biological fluids. Compared with biological assays, the major benefits of this method are specificity and rapidity. In particular, the determination of biologically inactive metabolites emphasizes that this technique plays an outstanding role for the analysis of antibiotics. This paper describes how the method can be used in the analysis of several antibiotics and demonstrates the efficacy of this method for clinical microbiology. Methods for the determination in biological fluids of acylaminopenicillins (azlocillin, mezlocillin, piperacillin and aspoxicillin), quinolones (ciprofloxacine, norfloxacine and ofloxacine), a penem (imipenem) and a cephalosporin (cefixime) are summarized. Furthermore, their application to in vitro studies and their trial in clinical studies are described.     

Reaction of primary thioamides withp-toluenesulfinic acid

The conversion of thioamides to the corresponding 1,2,4-thiadiazoles occurs upon heating primary thioamides with formaldehyde andp-toluenesulfinic acid in water instead of the formation of N-(tosylmethyl)thioamides.M. V. Lomonosov State Academy for Fine Chemical Technology, 117571 Moscow, Russia. Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 3, pp. 412–415, Marhc, 1997.