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141.
142.
Klaus C. Lück Franz J. Müller 《Journal of Quantitative Spectroscopy & Radiative Transfer》1977,17(3):403-409
The development of tunable cw dye lasers with an extremely narrow bandwidth of <20 MHz and high stability in frequency and amplitude, which operate in the wavelength region from 2800 to 3150 Å by frequency doubling, has made possible the quantitative proof of the presence of OH with high-resolution laser-absorption spectroscopy.A method is presented, which allows the simultaneous measurement of temperature and OH-concentration by tuning across a suitable rotational line. 相似文献
143.
Klaus H. Berkner David Leung Robert V. Pyle Alfred S. Schlachter J.Warren Stearns 《Physics letters. A》1977,64(2):217-218
Equilibrium charge-state fractions of 2.7–31 keV deuterium in strontium vapor are reported. The energy dependence of the D- equilibrium yield is discussed. The results are compared with the D- yield in cesium and magnesium vapors. 相似文献
144.
145.
Christian Reichardt Hans-Peter Erfurt Klaus Harms 《Phosphorus, sulfur, and silicon and the related elements》2013,188(5):1081-1092
Attempts at the oxidation of 3-ethyl-2-methylbenzothiazolium salt 2 with a variety of oxidizing reagents did not lead to the desired isochiral S -oxide 3 or achiral S , S -dioxide 4 , in some cases, however, unexpectedly to the ring-opened dimeric 2,2'-di( N -ethyl-acetamino)substituted diphenyl disulfane 5 , the molecular structure of which was confirmed by x-ray analysis. The synthesis of 2-methylbenzothiazole- S , S -dioxide 14 , reported by Zincke et al. in 1915, turned out to be not reproducible. \centerline{\epsfbox{:art:fig-01.jpg}} 相似文献
146.
Lars Carlsena Klaus Bechgaardb Claus S. Jacobsen Ib Johansen 《Phosphorus, sulfur, and silicon and the related elements》2013,188(1-2)
Abstract Tetrathiafulvalene S-oxide (TTF-ox) was first detected by mass spectrometry in samples of Tetrathiafulvalene (TTF) which had been exposed to oxygen. Pure TTF-ox was prepared by peracid oxidation of TTF and isolated as a relativly stable solid. Physical data will be presented. 相似文献
147.
A convenient three‐step route toward a functionalized pyrrole building block for novel anti‐inflammatory agents is reported. In contrast to previous strategies, the present approach focuses on inexpensive starting materials and application on a multigram scale. A high degree of functional diversity is demonstrated in various derivatives, and the scope and limitations of this route are discussed. Complementary to the described tetrasubstituted pyrroles, a novel ring‐closure protocol based on the Feist–Benary condensation affords trisubstituted analogues. 相似文献
148.
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
149.
150.
Industrial drug research is undergoing radical changes. Advances in molecular biology and gene technology have resulted in the development of test systems with which a very large number of substances can be screened for their biological activity. In order to keep pace with this high-throughput screening procedure, preparative chemists need to reconsider conventional synthetic strategies. 相似文献