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131.
A simple desalting procedure for the coupling of a polymer microchip injector to mass spectrometry is proposed. The overall process is based on the adsorption of proteins on a poly(vinylidene difluoride) (PVDF) membrane, which are then directly eluted in the spraying solution. This microchip-based approach has been successfully applied to small drugs, peptides and proteins originally diluted in phosphate-buffered saline (PBS). Moreover, when eluting the retained proteins in small volumes, a preconcentration is obtained. The combination of single-use, mass-produceable, low-sample-consumption, easy-to-automate, miniaturized polymer injectors with easy-to-handle solution-exchange membranes makes this system particularly amenable to screening applications. 相似文献
132.
One of the most useful results in modular representation theoryof finite groups is Green's indecomposability theorem [4]. Inorder to state it in a simple form, let us fix a complete discretevaluation ring O of characteristic 0 with algebraically closedresidue field F of characteristic p0. Unless stated otherwise,all our modules will be free of finite rank over O or F, respectively.In its most popular form, Green's theorem says the following. 相似文献
133.
134.
Batch extraction and polymerization of indole and 3-methylindole (skatole) with acidic cation exchange resins functioned as pseudo first-order reactions. Activation energies of 3.4 and 5.7 keal/mole indicated greater steric hindrance to skatole polymerization, as would be expected from 2,2′ bonding of skatole compared to 3,2′ bonding for indole. Linear polymerization occurred, although a heterocyclic ring opened at the trimer stage of poly(indole). 2-Methylindole did not polymerize. General acid-base catalysis caused unreproducible partial depolytnerization when the polymers were extracted from resin beads. Thus, compounds chromatographically separated probably were of lower degree of polymerization than were the polymers formed in the resin matrix. 相似文献
135.
The pulsed CO2-laser-induced multiphoton dissociation of n-butyl vinyl ether is studied. Comprehensive measurements have been performed for 9.6.μm and 10.6 μm irradiation. The corresponding dissociation product distributions show distinct differences for the two irradiation wavelengths, the most important finding being that acetylene is only produced at 9.6 μm. 相似文献
136.
137.
The absorption of oxygen by solutions of bis(triphenylphosphine)cobalt(II) chloride in allylamine in the presence of heterocyclic ligands has been studied. Novel complexes are formed in the presence of benzotriazole. A new class of trinuclear complexes has been discovered and studied by X-ray diffraction. Oxidation of triphenylphosphine takes place catalytically in the presence of oxygen under mild conditions. 相似文献
138.
139.
Dr. Hubert Tietz 《Mathematische Zeitschrift》1970,113(2):136-144
Ohne Zusammenfassung 相似文献
140.
J.-J. Bonnet D. Hubert F. Bonnet M. Bonnefoy A. Fleury L. Avan 《Physics letters. A》1979,70(2):99-102
This note presents the first measurement of the relative intensities of the radiative processes of the L shell of argon. The partial emission cross sections are deduced. Our data show that the radiative transitions within the excited ion are very sensitive to the incident electron energy. 相似文献