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1.
2.
M Riedel 《Journal of multivariate analysis》1985,16(2):241-252
Let X1, X2,…, be independent, identically distributed random variables. Suppose that the linear forms L1 = Σj=1∞ajXj and L2 = Σj=1∞bjXj exist with probability one and are identically distributed; necessary and sufficient conditions assuring that X1 is normally distributed are presented. The result is an extension of a theorem of Linnik (Ukrainian Math. J.5 (1953), 207–243, 247–290) concerning the case that the linear forms L1 and L2 have a finite number of nonvanishing components. This proof only makes use of elementary properties of characteristic functions and of meromorphic functions. 相似文献
3.
I. Kúdelka P.K. Misro J. Pospíšil H. Korbanka T. Riedel G. Pfahler 《Polymer Degradation and Stability》1985,12(4):303-313
The hydroperoxide decomposing efficiencies of dioctadecylsulfide (I), dioctadecyldisulfide (IV) and dioctadecyl 3,3-thio-dipropionate (VII) have been compared at 75°C and 85°C. The formation of oxidation products from (I) and (IV) has been checked. Experimental evidence is given of the important rôle of the activation of the molecule of (IV) by the presence of two sulfidic sulfur atoms compared with the activation of the sulfur atom in (VII) by the alkoxycarbonyl group in the beta position. The explanation of the high efficiency of disulfide has been based on the formation of thiosulfinate—the key intermediate for the generation of peroxidolytic species—in the first reaction step. 相似文献
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Efficient method for visualization and isolation of proteins resolved in polyacrylamide gels 总被引:3,自引:0,他引:3
R T Francis J R Davie M Sayre E Rocha F Ziemer G Riedel 《Journal of chromatography. A》1984,298(1):115-121
Polyacrylamide gel electrophoresis is a popular method used to purify proteins for reconstitution experiments, amino acid composition and sequence determinations. In this report we describe methods that will be of general use in the isolation and characterization of proteins and the benefits of substituting boric acid for glycine in the electrophoresis tray buffers. We also describe how proteins resolved in a variety of gel systems (including those containing sodium dodecyl sulfate) may be rapidly visualized with 8-anilino-1-naphthalene sulfonic acid and efficiently transferred to a second gel for two-dimensional gel analysis, or isolated by electroelution for subsequent characterization. 相似文献
6.
U. Wollenberger B. Neumann K. Riedel F. W. Scheller 《Fresenius' Journal of Analytical Chemistry》1994,348(8-9):563-566
Biosensors employing a biocatalyst on a different level of integration have been developed for monitoring environmental pollution. These probes range from laboratory specimen to commercial detectors applied to analyzers. Recent developments on amperometric enzyme and microbial biosensors are presented here. A monoenzymatic bulk-type carbon electrode is described for biosensing organic hydroperoxides in aqueous solutions; peroxidase is immobilized within the electrode body and the direct electron transfer between electrode and enzyme is measured. Both, reversible and irreversible inhibitors of acetylcholinesterase have been quantified by using a kinetically controlled acetylcholine enzyme sequence electrode. The inhibitory effect of pesticides such as butoxycarboxime, dimethoate, and trichlorfon could be quantified within 6 min in molar concentrations. Different multi-enzyme electrodes have been developed for the determination of inorganic phosphate. These sensors represent examples of sequentially acting enzymes in combination with enzymatic analyte recycling. Using this type of amplification nanomolar concentrations can be measured. 相似文献
7.
8.
Oswald Riedel 《Fresenius' Journal of Analytical Chemistry》1964,201(4):253-262
Zusammenfassung Zur Reinheitsbestimmung schmelzbarer, vorwiegend organischer Proben wurde eine kryoskopische Apparatur nachSmit gebaut. Sie arbeitet oberhalb 99 Mol-% im Halbmikrobereich, wobei der Absolutwert der Reinheit auf ±0,05 Mol-% genau meßbar ist. Die Probe, die ständig unter strömendem Stickstoff gehalten wird, umgibt als dünne Schicht ein Platin-Widerstandsthermometer, das sich in der Mitte eines elektrisch geheizten Aluminiumzylinders befindet. Konstanz der Wärmezufuhr wird gesichert durch Regelung der Temperaturdifferenz gegen ein gleichartiges zweites Thermometer, das dicht am geheizten Zylindermantel eingesteckt ist. Die Thermometer brauchen nicht geeicht zu werden. Die Regelung wird durch eine Doppel-Wheatstonebrücke vermittelt, deren einer Ausgang auf den Schreiber und deren anderer auf die Heizung wirkt. Die graphische Auswertung ist aus dem Zweiphasen-Diagramm fest-flüssig abgeleitet. Als Bezugsstandard ist eine zweite Probe zu messen, die man durch Verunreinigung der ursprünglichen Substanz um einen bekannten Betrag erhält.
Unter Mitarbeit von F.Weigand und R.Baumgart.
Herrn Dr.Ebinger, AEG-Meßgerätefabrik Berlin-Reinickendorf und Herrn Dipl.-Ing. Lutz, AEG-Büro Mannheim, habe ich für ihre große Bereitwilligkeit zu danken, mit der sie auf die Wünsche zur Bauart der Brücke eingingen. — Für Anregungen danke ich Herrn Dr.Kienitz. 相似文献
Summary A cryoscopic apparatus for the purity assay of fusible, mostly organic samples was built afterSmit. It works in the half-micro scale above 99 mole%, where the absolute value of the purity will lie within ±0.05 mole%. The sample, which is always kept under streaming nitrogen, surrounds as a thin layer a platinum resistance thermometer that stands in the center of an electrically heated aluminium cylinder. A constant supply of heat is ensured by controlling the temperature difference against a second thermometer of the same kind, which is inserted near the heated periphery of the cylinder. It is not necessary to calibrate the thermometers. Control is mediated by a double Wheatstone bridge, the one output of which acts on the recording device, the other on the heater. The graphical evaluation of the records derives from the two-phase diagram solid-liquid. As a referential instance, a second sample has to be measured, which is obtained from the specimen through artificial contamination by a known amount.
Unter Mitarbeit von F.Weigand und R.Baumgart.
Herrn Dr.Ebinger, AEG-Meßgerätefabrik Berlin-Reinickendorf und Herrn Dipl.-Ing. Lutz, AEG-Büro Mannheim, habe ich für ihre große Bereitwilligkeit zu danken, mit der sie auf die Wünsche zur Bauart der Brücke eingingen. — Für Anregungen danke ich Herrn Dr.Kienitz. 相似文献
9.
The spinels of the system LixMn1?xV2O4 (0 ? x ? 1) have been prepared at 700–750°C from LiV2O4 and MnV2O4. The lattice constants decrease linearly with increasing x. In the region x>0.75, the d-electrons of V should be delocalized as the VV distances are lower than the critical VV separation of 2.94 Å. Experimentally, the samples with x>0.6 show no IR absorption bands and the Seebeck coefficient is near zero. The Seebeck coefficient can be described with a model of intermediate polarons and can be expressed by the equation . 相似文献
10.
AES depth profiles on ceramic powders (untreated/hydrolyzed/oxidized/ (Al, Y)2O3 coated Si3N4, [BaO, SiO2] coated Al2O3) are feasible on thin, homogeneous layers or m sized agglomerations prepared on an Au foil. By means of the depth profiles one can qualitatively characterize the coating around the particles. Factor analysis of the depth profiles on the differently treated Si3N4 powders suggests the existence of an Si2N2O phase on the oxidized sample.Dedicated to Professor Günther Tölg on the occasion of his 60th birthday 相似文献