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51.
Damm M Holzer M Radspieler G Marsche G Kappe CO 《Journal of chromatography. A》2010,1217(50):7826-7832
An efficient microwave-assisted high-throughput protein hydrolysis protocol was developed utilizing strongly microwave absorbing silicon carbide-based microtiter platforms. The plates are equipped with 20 bore holes having the proper dimensions for holding standard screw-capped HPLC/GC vials. Due to the possibility of heating up to four heating platforms simultaneously (80 vials), parallel microwave-assisted acid hydrolyses can be performed under carefully controlled conditions significantly reducing the overall time required for protein hydrolysis and the subsequent evaporation step required for larger volumes of acid. An extensive optimization of the hydrolysis conditions has demonstrated that 5min irradiation at 160°C with 6N HCl leads to comparable results in terms of total and individual amino acid recovery as the traditional method requiring 24h heating at 110°C. Complete hydrolysis of several proteins and synthetic peptides was performed using 25μg of sample material and 100μL of 6N HCl in a dedicated low-volume HPLC/GC vial. Since the hydrolysis and subsequent analysis can be performed from the same vial, errors caused by sample transfer can be minimized. Control experiments have demonstrated that the observed rate enhancements are the result of a purely thermal/kinetic effect as a consequence of the considerable higher reaction temperatures. 相似文献
52.
Kumar R Spuesens T Mechet P Kumar P Raz O Olivier N Fedeli JM Roelkens G Baets R Van Thourhout D Morthier G 《Optics letters》2011,36(13):2450-2452
Using a 7.5 μm diameter disk fabricated with III-V-on-silicon fabrication technology, we demonstrate bias-free all-optical wavelength conversion for non-return-to-zero on-off keyed pseudorandom bit sequence (PRBS) data at the speed of 10 Gbits/s with an extinction ratio of more than 12 dB. The working principle of such a wavelength converter is based on free-carrier-induced refractive index modulation in a pump-probe configuration. We believe it to be the first bias-free on-chip demonstration of all-optical wavelength conversion using PRBS data. All-optical gating measurements in the pump-probe configuration with the same device have revealed that it is possible to achieve wavelength conversion beyond 20 Gbits/s. 相似文献
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Petra Schulte Gunther Schmidt Claus-Peter Kramer Adolf Krebs Ulrich Behrens 《Journal of organometallic chemistry》1997,530(1-2):95-100
The strained cycloheptynes 2a, 2b and 2c react with copper(I) chloride to form the dinuclear complexes [CuCl(cycloheptyne)]2 3a, 3b and 3c respectively. X-ray diffraction studies on all three compounds 3 show an increase in strength of the copper-alkyne bond with increasing deformation of the alkyne moiety from the ideal 180°. Thus going from the least strained alkyne (2c) to the most strained one (2a), the Cu-C bond lengths in the corresponding complexes decrease from 197.5 pm (3c) to 194.9 pm (3a). The C≡C-C angles increase from 145.6° (3a) over 147.4° (3b) to 151.6° (3c).
Zusammenfassung
Die gespannten Cycloheptine 2a, 2b und 2c reagieren mit Kupfer(I)—chlorid unter Bildung der zweikernigen Komplexe [CuCl(cycloheptin)]2 3a, 3b und 3c. Röntgenstrukturanalysen von allen drei Verbindungen 3 zeigen, daβ die Stärke der Kupfer—Alkin-Bindung zunimmt je mehr das ganze Alkinsystem vom idealen 180°-Winkel abweicht. Geht man vom am wenigsten gespannten Alkin (2c) zum gespanntesten (2a), so nehmen die Cu-C-Bindungslängen in den entsprechenden Komplexen von 197.5 pm (3c) auf 194.9 pm (3a) ab. Die C≡C-C-Winkel werden von 145.6° (3a) über 147.4° (3b) nach 151.6° (3c) hin gröβer. 相似文献
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58.
Gunther Schmidt 《Numerische Mathematik》1986,50(3):337-352
Summary This paper analyses the convergence of spline collocation methods for singular integro-differential equations over the interval (0.1). As trial functions we utilize smooth polynomial splines the degree of which coincides with the order of the equation. Depending on the choice of collocation points we obtain sufficient and even necessary conditions for the convergence in sobolev norms. We give asymptotic error estimates and some numerical results. 相似文献
59.
Zoltán Buczolich Gunther Leobacher Alexander Steinicke 《Mathematische Nachrichten》2023,296(10):4778-4805
We construct a Hölder continuous function on the unit interval which coincides in uncountably (in fact continuum) many points with every function of total variation smaller than 1 passing through the origin. We conclude that this function has impermeable graph—one of the key concepts introduced in this paper—and we present further examples of functions both with permeable and impermeable graphs. Moreover, we show that typical (in the sense of Baire category) continuous functions have permeable graphs. The first example function is subsequently used to construct an example of a continuous function on the plane which is intrinsically Lipschitz continuous on the complement of the graph of a Hölder continuous function with impermeable graph, but which is not Lipschitz continuous on the plane. As another main result, we construct a continuous function on the unit interval which coincides in a set of Hausdorff dimension 1 with every function of total variation smaller than 1 which passes through the origin. 相似文献
60.
Neutral impact collision ion scattering spectroscopy (NICISS) was used to determine the surface structure of three ionic liquids, 1-hexyl-3-methylimidazolium [C(6)mim], 1-octyl-3-methylimidazolium [C(8)mim], 1-decyl-3-methylimidazolium [C(10)mim] tetrafluoroborates [BF(4)]. Concentration depth profiles of the elements in an ionic liquid (IL) homologous series with a common anion were obtained. We show that separation between the oppositely charged ions is seen for all three ionic liquids, resulting in an electrical double layer formation. The surface charge shifts from more positive to more negative with increasing aliphatic chain length. 相似文献