Die Erscheinungen bei der konduktometrischen Titration des Systems H3BO3-H2SO4-MgSO4

Ohne Zusammenfassung     

Oxidation and Reduction Processes During NO x Removal with Corona-Induced Nonthermal Plasma

In this paper, the NO-to-NO ₂ conversion in various gaseous mixtures is experimentally investigated. Streamer coronas are produced with a dc-superimposed high-frequency ac power supply (10–60 kHz). According to NO _x removal experiments in N ₂ +NO _x and N ₂ +O ₂ +NO _x gaseous mixtures, it is supposed that the reverse reaction NO ₂ +ONO+O ₂ may not only limit NO ₂ production in N ₂ +NO _x mixtures, but also increase the energy cost for NO removal. Oxygen could significantly suppress reduction reactions and enhance oxidation processes. The reduction reactions, such as N+NON ₂ +O, induce negligible NO removal provided the O ₂ concentration is larger than 3.6%. With adding H ₂ O into the reactor, the produced NO ₂ per unit removed NO can be significantly reduced due to NO ₂ oxidation. NH ₃ injection could also significantly decrease the produced NO ₂ via NH and NH ₂ - related reduction reactions. Almost 100% of NO ₂ can be removed in gaseous mixtures of N ₂ +O ₂ +H ₂ O+NO ₂ with negligible NO production.     

Isoenzyme der Aspartat-Aminotransferase aus dem Endosperm von keimenden Rizinussamen

The amino acid specificity of the aminotransferase activities of glyoxysomes, mitochondria and of the soluble fraction from the endosperm of germinating castor beans was tested with -ketoglutarate as amino acceptor. Glyoxysomes exhibit aspartate aminotransferase (E.C. 2.6.1.1) together with comparatively high asparagine (E.C. 2.6.1.14) and glutamine aminotransferase (E.C. 2.6.1.15) activities. Mitochondria and the soluble fraction contain alanine aminotransferase (E.C. 2.1.2) activity in addition to the glyoxysomal aminotransferases. Asparagine and glutamine aminotransferase activities are much lower in the soluble fraction than in the organelles. A number of isoenzymes of aspartate aminotransferase of mitochondria and glyoxysomes could be separated with the aid of polyacrylamide gel electrophoresis.

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Alkoxy(acyloxy)silanes

Conclusions Alkoxychlorosilanes react with trimethylacyloxysilanes to give the difficultly accessible alkoxy(acyloxy)silanes of general formula (RO)_nSi(OCOR)_4-n (n=1–3) in 60–80% yields.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 3, pp. 671–674, March, 1989.