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601.
Laser micro mass spectrometry (LAMMS) was used for organic micro-analysis of bulk polymeric samples with a lateral resolution of about 3 m. The experiments were performed with a LAMMA 1000 instrument which was modified by the addition of a transmission illumination system for the observation of thin sections and a heating/cooling sample stage with sample transfer lock. It was found that crystallites or agglomerates of low-molecular-weight compounds could be identified by both molecular ions and characteristic fragments, and cyclic oligomers in bulkpolyamide 6 could be detected as cationized species if cations were present in the sample. On the other hand, the identification of high-molecular-weight polymers, e.g., in inclusions, was based on structurally significant fragments of the repeat unit. For samples with a low absorbance at the laser wavelength used, this fragment ion yield could be maximized by evaporating a thin absorbing layer onto the sample surface. If thin sections could be prepared from a sample a micro-FTIR analysis was possible. Such experiments gave results which were complementary to those of the corresponding LAMMS analysis. 相似文献
602.
Raphael Lamed Rina Kenig Ely Morgenstern Jose Francisco Calzada Fabiola De Micheo Edward A. Bayer 《Applied biochemistry and biotechnology》1991,27(2):173-183
The cellulosome, the multienzyme complex of the cellulase system ofClostridium thermocellum, that mediates the solubilization of insoluble cellulose, is strongly inhibited by the major end product, cellobiose. By
combining a purified β-glucosidase fromAspergillus niger with the cellulosome, accumulated cellobiose was hydrolyzed thereby resulting in a dramatic enhancement (up to 10-fold) of
cellulose degradation. The observed enhancement was expressed both in the rate and degree of solubilization of microcrystalline
cellulose, compared with that observed for the unsupplemented cellulosome. Near-complete conversion of cellulose to glucose
could be obtained from dense substrate suspensions (up to at least 200 g/L). 相似文献
603.
604.
J. W. Marden J. C. Ghosh H. T. Beans Dorothea R. Mossman J. Ciochina K. Roesch W. Werz H. Mathesius J. Arend H. Schnellenbach F. Spindeck A. Angeletti L. Moser K. Neumayer K. Winter J. Singer W. R. Schoeller C. Jahn H. W. Webb A. R. Powell H. Ginsberg F. P. Treadwell A. Gautier und H. Hueber 《Fresenius' Journal of Analytical Chemistry》1933,93(5-6):203-222
Ohne Zusammenfassung 相似文献
605.
A. Bayer G. Mossler Fernau Frey Anneler Siegfried W. O. Emery G. C. Spencer Norah Radford G. Brewer und C. Monthulé 《Fresenius' Journal of Analytical Chemistry》1920,59(7):333-336
Ohne Zusammenfassung 相似文献
606.
607.
A. R. Bayer und G. Bodmer 《Fresenius' Journal of Analytical Chemistry》1937,111(1):41-43
Ohne Zusammenfassung 相似文献
608.
W. Bayer 《Archiv der Mathematik》2000,75(4):272-279
This paper disproves the widespread opinion that chaos may appear in non-linear connections only. The common differential operator, which assigns the first derivative to each function, is linear and chaotic in the sense of Li and Yorke. 相似文献
609.
Well-prepared periodic arrays of silver nanoparticles are investigated by means of linear and non-linear photoemission electron microscopy. The structures show homogeneous photoemission for UV excitation in the linear photoemission regime whereas striking inhomogeneities are mapped in the case of the nonlinear (2 photon) excitation using ultrashort 400 nm laser pulses. A detailed analysis enables to assign these inhomogeneities to defect induced electron momentum transfer processes only effective for the 2 photon excitation process. We propose this mechanism to be of relevance for the appearance of so-called hot spots in nonlinear photoemission as identified in other 2PPE studies in the past. Furthermore, the complementarity between all-optical studies and nonlinear photoemission studies of localized surface plasmons in nanoparticles is discussed. 相似文献
610.
K. J. Bayer 《Fresenius' Journal of Analytical Chemistry》1886,25(1):180-183
Ohne Zusammenfassung 相似文献