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101.
Chen T Barton SC Binyamin G Gao Z Zhang Y Kim HH Heller A 《Journal of the American Chemical Society》2001,123(35):8630-8631
102.
103.
G. Gritzner P. Rechberger Prof. Dr. Viktor Gutmann 《Monatshefte für Chemie / Chemical Monthly》1976,107(3):809-814
The influence of solvents on the redox behaviour of bistriphenylphosphinomercury perchlorate has been investigated by polarographic, voltammetric and potentiometric methods. The electrode process was found to be reversible in acetonitrile, propylene carbonate, N,N-dimethylformamide and dimethyl sulfoxide. An irreversible process was observed in nitromethane employing the dropping mercury electrode as well as in N,N-dimethylthioformamide and N-methyl-2-thiopyrrolidinone employing the rotating platinum electrode. Half wave potentials and diffusion coefficients have been measured. A linear relationship between theE
1/2 and the donor number (DN) of the solvent has been found for the reversible electrode reactions. Ligand replacement occurs in N,N-dimethylthioformamide and N-methyl-2-thiopyrrolidinone.
Mit 1 Abbildung 相似文献
Mit 1 Abbildung 相似文献
104.
Zh. A. Abdurakhmanova L. N. Abdusalyamova V. V. Kim Sh. I. Salikhov 《Chemistry of Natural Compounds》1994,30(1):92-96
The Ca2+-phospholipid-dependent protein kinase from cottonplant shoots was purified by chromatography on DEAE-Sepharose CL-6B, and then on phenyl-Sepharose CL-4B. According to electrophoresis in PAAG, the enzyme was practically homogeneous and had a molecular mass of 57 kDa. In the presence of Ca2+ alone, the enzyme was activated to only a slight degree. Under the combined action of Ca2+ and a phospholipid the action of the enzyme rose severalfold. A determination of amino acid specificity showed that the protein kinase isolated was a serine- and threonine-specific protein kinase.A. S. Sadykov Institute of Bioorganic Chemistry, Academy of Sciences of the Republic of Uzbekistan, Tashkent, fax 627071. Translated from Khimiya Prirodnykh Soedinenii, No. 1, pp. 100–105, January–February, 1994. 相似文献
105.
106.
Ivanisevic A McCumber KV Mirkin CA 《Journal of the American Chemical Society》2002,124(40):11997-12001
We describe a new combinatorial method for studying the exchange between solution adsorbates and nanoscale features within libraries generated via dip-pen nanolithography. Four different compounds, 1-octadecanethiol, 16-mercaptohexadecanoic acid, ferrocene (11-mercaptoundecyl), and ferrocene (11-mercapto-1-oxoundecyl), are studied on amorphous and single-crystal gold substrates. This series of adsorbates allows us to compare the exchange properties of patterns of nanoscale features as a function of composition, feature size, and type of underlying substrate. Moreover, these properties can be compared and contrasted with bulk SAM properties. The novel strategy provides not only a method for initiating site-specific exchange processes but also a way of extracting kinetic information about the rate of such processes in situ. 相似文献
107.
Reaction of trienes with α,β-unsaturated aldehydes produces bicyclic products via a tandem Diels-Alder/ene reaction. The adduct from tiglic aldehyde was converted into isoligularone by conversion to a furan followed by benzylic oxidation. 相似文献
108.
Prof. Dr. Stefan Smoliński Janusz Jamrozik Maria Jamrozik 《Monatshefte für Chemie / Chemical Monthly》1977,108(5):1145-1151
We have obtained four new bispirane systems in which both spiroatoms are vicinal atoms in cyclopropane or cyclobutane rings and in which the heterocyclic component has the basic structure of 1,4-dioxep-2-ene. We have shown that from two possibilities (bispiran, propellan) the general reaction leads only to a bispiran system. To the bispiran2 exhibiting the highest hyperchromism we ascribed the bispirocoplanar conformation (Fig. 1).
Mit 3 Abbildungen 相似文献
Mit 3 Abbildungen 相似文献
109.
Summary A sensitive method has been developed for analysis of trace amounts of arsenic in biological materials using the heteropoly blue method. The method employs a closed apparatus and a nitrogen atmosphere, and allows the detection of arsenic in ppm concentration using samples of 100 mg.
Presented at the 6th Annual Northeast Regional Meeting of the American Chemical Society, Burlington, Vermont, August 19, 1974. 相似文献
Zusammenfassung Eine empfindliche Methode zur Bestimmung von Arsenspuren in biologischem Material im Wege der Molybdänblaumethode wurde ausgearbeitet. Man arbeitet dabei in einer geschlossenen Apparatur in Stickstoffatmosphäre und kann so in 100-mg-Proben Arsenkonzentrationen in der Größenordnung von ppm bestimmen.
Presented at the 6th Annual Northeast Regional Meeting of the American Chemical Society, Burlington, Vermont, August 19, 1974. 相似文献
110.
Prof. G. Liptay 《Journal of Thermal Analysis and Calorimetry》1994,42(2-3):293-294