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41.
Microchimica Acta - Mit der turbidimetrischen Strychninnitrat-Methode für Phosphorspurenbestimmung nach der Version von Hegedüs und Dvorszky kann man nur dann ausgezeichnete... 相似文献
42.
H. W. Dürbeck 《Analytical and bioanalytical chemistry》1970,251(2):108-111
Separation of isomeric aromatic hydrocarbons from each other has been obtained using packed columns and Bentone 34 modified with silicone oil and lanolin. For maximum resolution the proportions of the modifying agents are very important. Retention data and chromatograms of two different column types are given (column 1∶6% Bentone 34; 2,5% lanolin; 1,5% silicone oil. Column 2∶10% silicone oil; 5% bentone 34; 4% lanolin) 相似文献
43.
44.
An immobiline DryStrip application method enabling high-capacity two-dimensional gel electrophoresis 总被引:5,自引:0,他引:5
Sabounchi-Schütt F Aström J Olsson I Eklund A Grunewald J Bjellqvist B 《Electrophoresis》2000,21(17):3649-3656
In the field of proteomics the need to detect low-abundance cellular components, such as regulatory proteins, is of critical importance. Two-dimensional polyacrylamide gel electrophoresis (2-D PAGE) is one of the most commonly used separation tools for these biological investigations. In this paper we report an alternative micropreparative 2-D PAGE sample application method, called the "paper bridge loading" method. This method makes it possible to apply a larger sample volume to commercially available immobilized pH gradient (IPG) strips. The Vh products required for focusing are only marginally longer than those used in analytical experiments. The method was compared to traditional cup loading and in-gel rehydration. With 18 cm long narrow-range Immobiline DryStrip pH 4.5-5.5, the "paper bridge" method allowed the application of 10 mg human plasma proteins compared to 3 mg with traditional loading methods. The corresponding figures using Escherichia coli sample was found to be 6 mg and less than 2 mg, respectively. The paper bridge method also showed the best results in terms of spot resolution and separation of high molecular weight proteins. 相似文献
45.
46.
Modern activation analysis requires the application of efficient data processing for the evaluation of theγ-spectra of samples containing several radionuclides, especially if preceding radiochemical separations are to be largely or completely eliminated. The essential aspects of two programs for quantitative determinations and qualitative identifications are described. These programs are based on the least squares analysis of the total spectrum and the search, arrangement and processing of the photopeaks. With respect to their details the programs are adapted for application on the computer IBM-360/75. 相似文献
47.
Zusammenfassung Umsetzung von 5,6-Dimethoxy- und [4,5,6-Trimethoxy-benzo[b]thienyl-(3)]-essigsäure mit PCl5 lieferte die methoxysubstituierten [Benzo[b]thienyl-(3)]-essigsäurechloride, die mit sekundären Aminen zu den entsprechenden Amiden reagierten.Die homologen Verbindungen mit einer C3-Brücke wurden durchArndt-Eistert-Reaktion des Diazomethylketons in Gegenwart der entsprechenden sekundären Amine erhalten.
Reaction of 5.6-dimethoxy- and [4.5.6-trimethoxybenzo[b]-thienyl-(3)]-acetic acid with PCl5 gave the methoxy-substituted [benzo[b]thienyl-(3)]-acetic acid chlorides, which reacted with secondary amines to the corresponding amides.The homologous compounds with a C3-bridge were synthesized viaArndt-Eistert reaction of the diazomethyl ketone in presence of the corresponding secondary amines.相似文献
48.
E. Brüning 《Czechoslovak Journal of Physics》1987,37(4):492-502
A definition of local functions of generalized free fields is suggested. Their concrete form is determined in a fairly general setting by analysing realizations of locality. A huge class of new models of relativistic quantum fields results in this way.Presented at the International Conference Selected Topics in Quantum Field Theory and Mathematical Physics, Bechyn, Czechoslovakia, June 23–27, 1986. 相似文献
49.
Günter F. Steinke 《Results in Mathematics》1987,12(1-2):207-221
A new rather large family of locally compact 2-dimensional topological Laguerre planes is introduced here. This family consists exactly of those Laguerre planes which can be obtained by pasting together two halves of the classical real Laguerre plane along a circle suitably. Isomorphism classes and automorphism groups of these planes are determined. Together with [9] this gives a complete classification of all semicalssical topological flat Lguerre planes. 相似文献
50.