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21.
Ohne Zusammenfassung 相似文献
22.
G. Buchbauer H. Spreitzer B. Öckher C. Pretterklieber I. Piringer P. Wolschann 《Monatshefte für Chemie / Chemical Monthly》1995,126(4):467-472
Summary Guided by molecular modeling studies, the synthesis of the title compound is described. The organoleptic evaluation proved the predicted real sandal like odour of (Z)-dehydro-homo--santalol.
Aus den Diplomarbeiten von C.P. (1991), I.P. und B.Ö. (1992), Universität Wien 相似文献
23.
Abramowicz H Belusevic R Blondel A Blümer H Böckmann P Brummel HD Buchholz P Burkhardt H Debu P Duda J Dydak F Falkenburg B Fiedler M Geiges R Geweniger C Grant AL Guyot C Hagelberg R Hepp V Hughes EW Kampschulte B Keilwerth H Kleinknecht K Knobloch J Krasny M Królikowski J Kurz N Lipniacka A Merlo J Müller E Para A Perez P Perrier F Pollman D Ranjard F Renk B Schuller J Taureg H Tittel K Turlay R Vallage B Wachsmuth H Wotschack J 《Physical review letters》1986,57(3):298-301
24.
Shoeib T Cunje A Hopkinson AC Siu KW 《Journal of the American Society for Mass Spectrometry》2002,13(4):408-416
Collision-induced dissociation experiments on the Ag+-phenylalanine complex using several collision energies were shown to yield ten different fragment ions. Unambiguous assignment of these fragment ions were made by careful analysis of deuterium labeling experiments. The losses of H2O, CO, CO2, and AgH were commonly observed; also encountered were the losses of H2, Ag, and H. Deuterium labeling experiments and density functional calculations have been employed to probe fragmentation mechanisms that account for all experimental results. 相似文献
25.
I. G. Voigt-Martin Z. X. Zhang D. H. Yan A. Yakimanski R. Matschiner P. Krämer C. Glania R Wortmann N. Detzer D. Schollmeyer 《Colloid and polymer science》1997,275(1):18-37
4-Dimethylamino-3-cyanobiphenyl (4-DMA-3-CB) was characterized with respect to linear and nonlinear optical properties in
a crystal as well as in solution. The crystal structure was studied dependent on the crystallization conditions. It is shown
that the crystal structure exhibiting NLO-activity can completely be solved by a combination of electron diffraction and computer
modeling. There are four molecules per unit cell in the space group Pna21 with dimensions a=10.28 Å, b=22.64 Å, c=5.27 Å. From this model structure the values and orientation of the dipole μ and static second order polarizability β can
be calculated. Their relevance to the values obtained by a combination of polarization dependent measurements of Electric
Field Induced Second Harmonic Generation (EFISH) and Hyper-Rayleigh-Scattering (HRS) in solution are discussed. The molecular
second order polarizability tensor was found to be dominated by one single component. The orientations of the dipole and the
vectorial parts of the second order polarizability delivered by the semiempirical calculations are in good agreement with
the results of the EFISH and HRS-measurements and allow a deeper insight into the nonlinear optical properties of the crystal.
Received: 15 April 1996 Accepted: 21 June 1996 相似文献
26.
Binding of bis-picolylamine-naphthalene diimide-peptide nucleic acid conjugates to complementary DNA is strongly dependent upon Zn2+; ultimately, hybridization is switched ON in the presence muM Zn2+. 相似文献
27.
This study aims to clarify the effects of carbon activation type and physical form on the extent of adsorption capacity and
desorption capacity of a bi-solute mixture of phenol and 2-chlorophenol (2-CP). For this purpose, two different PACs; thermally
activated Norit SA4 and chemically activated Norit CA1, and their granular countertypes with similar physical characteristics,
thermally activated Norit PKDA and chemically activated Norit CAgran, were used. The thermally activated carbons were better
adsorbers for phenol and 2-CP compared with chemically activated carbons, but adsorption was more reversible in the latter
case. 2-CP was adsorbed preferentially by each type of activated carbon, but adsorption of phenol was strongly suppressed
in the presence of 2-CP. The simplified ideal adsorbed solution (SIAS) model underestimated the 2-CP loadings and overestimated
the phenol loadings. However, the improved and modified forms of the SIAS model could better predict the competitive adsorption.
The type of carbon activation was decisive in the application of these models. For each activated carbon type, phenol was
desorbed more readily in the bi-solute case, but desorption of 2-CP was less compared with single-solute. This was attributed
to higher energies of 2-CP adsorption. 相似文献
28.
H. A. Ergül S. Topcuo?lu E. Ölmez Ç. K?rbaşo?lu 《Journal of Radioanalytical and Nuclear Chemistry》2006,268(1):133-136
Summary Radionuclide (137Cs, 238U, 232Th and 40K) concentrations were determined in a sediment trap and bottom sediment samples collected from a station at the eastern Turkish
coast of the Black Sea. The specific activity of the 137Cs radionuclide in the settling particles ranged from 0.04±0.01 to 0.10±0.02 Bq. g-1dry weight. The calculated flux rate of the 137Cs was between 0.37 and 2.59 Bq. m-2. d-1in the sampling periods of 2002 and 2003. The 137Cs concentration in the bottom sediment profile were between 0.039±0.013-9.083±0.017 Bq. g-1dry weight in the same station. The vertical profile of the radionuclides suggests that they have little mobility during the
17 years after the Chernobyl accident. 相似文献
29.
8-Hydroxyquinoline (8-HOQ) is known as an important chelating agent for several metal ions. This compound is practically insoluble in water. For this reason, in this study its water soluble sulfate salt has been used for complexing uranyl ions and the stability constants of the complex have been determined. The Irving-Rosotti method computing the Calvin-Bjerrum pH-titration data, was applied. Finally, the stability constants of the complex formed between (8-HOQN-H)2SO4 and uranyl ions were found to be lgK1=8.25 and lgK2=4.15, the overall stability constant being {ie55-1}. 相似文献
30.
K. Özker A. Sungur M. Ercan N. Ardagil N. Aydin 《Journal of Radioanalytical and Nuclear Chemistry》1987,118(3):201-208
The labelling of human serum albumin /HSA/ with99mTc has been investigated using a chemical method /stannous citrate/ and electrolytically generated tin/II/ ions. A comparative study of various chemical parameters and current intensities has been carried out in order to find the optimal conditions for labelling. The labelling yield was over 95%, for the chemical and electrolytical methods. 相似文献