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The oxidation of alkyl chlorides and bromides with dimethyl sulfoxide has been performed in the presence of sodium iodide. This method allows a convenient one-step procedure for the preparation of aldehydes from alkyl chlorides and bromides. 相似文献
44.
David Gode Christian Schmitt Matthias Engel Dietrich A. Volmer 《Analytical and bioanalytical chemistry》2014,406(12):2841-2852
Enzyme-catalyzed reactions play key roles in disease pathology, thus making them relevant subjects of therapeutic inhibitor screening experiments. Matrix-assisted laser desorption/ionization (MALDI) assays have been demonstrated to be able to replace established screening approaches. They offer increased sample throughput, but care must be taken to avoid instrumental bias from differences in ionization efficiencies. We compared a MALDI-triple-quadrupole (QqQ) method for the Dyrk1A peptide substrate woodtide to LC–MS, liquid chromatography with ultraviolet detection (LC–UV), luminescence, and radiometric assays. MALDI measurements were performed on a MALDI-QqQ instrument in the multiple-reaction monitoring mode. Different MALDI conditions were investigated to address whether matrix type, sample support, and MRM- or SIM-based detection conditions can be used to accommodate the molar responses of substrate peptide and its phosphorylated form. UV detection served as a reference method. The impact of MALDI matrix on IC50 values was small, even considering that matrix preparations were used that are known to alleviate response differences. IC50 values determined by MALDI were ca. 2-fold lower than those determined by LC–UV. Although MALDI generated lower ion yields for the phosphorylated peptide than for the peptide substrate, we found that a correction of compound potencies was readily possible using correction factors based on unbiased LC–UV results. A thorough method development delivered a robust assay with excellent performance (Z′ > 0.91) that was close to that seen for LC–UV. Figure
? 相似文献
45.
Third-order nonlinear optical susceptibility, χ(3) of symmetrically octa-substituted metal-free phthalocyanine thin films measured by the third-harmonic generation technique are reported. The metal-free phthalocyanine has been found to show a χ(3) (−3ω; ω,ω, ω) value as large as 7.73×10−12 esu at 1.80 μm. The figure of merit, χ(3)/α, was estimated to be 4.17×1017 esu cm at 1.05 μm and 6.97×1016 esu cm at 1.65 μm. Both linear and third-order optical properties of liquid-crystalline metal-free phthalocyanines are discussed 相似文献
46.
The Vickers indentation hardness of Hg1−xCdxTe has been measured as a function of composition x using monocrystalline samples of Bridgman and THM crystals and polycrystalline starting material at room temperature. The microhardness varied between 220 MPa (x=0) and 440 MPa (x=1), showing a maximum of 850 MPa at x ∼ 0.75, and was different between monocrystalline and polycrystalline samples. The “hardening rate” dH/dx is strongly dependent on the composition range and is discussed in context with solid solution hardening due to elastic interactions of solute atoms with gliding dislocations and ordering effects. 相似文献
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A. Engel 《Crystal Research and Technology》1980,15(12):1439-1446
Starting from the general demands made upon semiconductor surfaces (measuring samples, substrates) and the critical material properties, the boundary conditions for the surface preparation of substances of low hardness are stated and technological variants for Bi1−xSbx, Pb1−xSnxTe, and PbS1−xSex are presented. The results show that almost defectfree surfaces of a high quality can be produced in a repeatable way. The depths of significant and detectable damages are determined depending on the technique in question. 相似文献
49.
L. Hock F. H. Müller H. Thiele Flügge H. Erbring F. V. A. Engel Sippel E. Gruner R. Jäger 《Colloid and polymer science》1951,122(3):179-182
Ohne Zusammenfassung 相似文献
50.