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991.
The potential of a direct, restricted step, second order MC SCF computer program is illustrated with a large configuration space calculation containing 24156 configuration state functions on the 3B1 state of methylene. 相似文献
992.
Steen Honoré Hansen Per Helboe Mogens Thomsen 《Trends in analytical chemistry : TRAC》1985,4(9):233-237
A new approach to reversed-phase high-performance liquid chromatography has been developed and investigated in some detail. Bare silica is used as the column packing material with an aqueous eluent containing a buffer, an organic solvent as the modifier and a long-chain quaternary ammonium ion. The eluent exhibits a high affinity to the silica surface at pH values above 5, thus, dynamically, forming a nonpolar stationary phase. 相似文献
993.
The electronic structure of 1,4,5-triaza-cyclohepta-2,6-diene has been studied. The treatment accounts for the failure of detecting, by experiment, a cyclic conjugation in this and related seven membered ring systems.
Zusammenfassung Die Elektronenstruktur des 1,4,5-triaza-cycloheptadien-2,6 wurde theoretisch untersucht. Das Ergebnis erklärt das Mißlingen von Versuchen, in diesem und verwandten Siebenringsystemen zyklische Konjugation aufzufinden.
Résumé La structure électronique du 1,4,5-triaza-cycloheptadiène-2,6 a été étudiée. Le résultat explique pourquoi une conjugaison cyclique n'a pas été trouvée expérimentalement ni dans ce composé ni dans d'autres systèmes cycliques semblables à sept membres.相似文献
994.
Herbert Hansen 《Zeitschrift für Physik A Hadrons and Nuclei》1963,174(2):231-239
The scintillation light yield of thin trans-stilbene, para-terphenyl and anthracene crystals and an organic plastic scintillator bombarded with α-particles of ThB has been measured as a function of temperature betweent=20° C and the melting point. The light yield of all the specimens investigated has been found to be reduced with increasing temperature. In all cases at the melting point the light yield will be zero. The scintillation anisotropy of the organic crystal scintillators also has been investigated over the range of temperature mentioned above, and there it is independent of temperature and retains the value measured at room temperature. 相似文献
995.
The temperature dependence of the saturation magnetization of a series of ionimplanted YIG films is presented. The films were implanted with neon ions at an energy of 450 keV; the dose ranged from 2 to 5*1014 ions/cm2. The experimental data can be described by the molecular field theory showing that the ion-implanted part of the film can be approximated as consisting of two regions each having their own magnetization and Curie temperature. The values of these magnetic parameters vary as a function of dose and differ strongly from the values for pure YIG. 相似文献
996.
997.
Sverre Storøy 《BIT Numerical Mathematics》1967,7(3):216-225
The present paper describes a simple method to find an indicator of the error in solutions found by a procedure using the simplex-technique, and also describes a method for improving these solutions to any desired accuracy provided certain conditions are met. 相似文献
998.
999.
1000.
Summary The aggregation behaviour of zinc-free insulin has been studied by small-angle neutron scattering as a function of protein
concentration,pH, and ionic strength of the solution. The distance distribution functions for the 12 samples have been obtained by indirect
Fourier transformation. The weight-averaged molecular mass and thez-averaged radius of gyration were determined. Both quantities vary systematically with the experimental conditions. They increase
with decreasingpH and with increasing ionic strength. The radius of gyration scales as a power law of the weight-average mass with the exponent
0.44. A similar scaling is found for a set of oligomers structures based on the crystal structure of zinc-free insulin. The
mass distribution between the oligomers was determined by a model based on these oligomers. The results from this model and
the Fourier transformations have been compared to an equilibrium model recently introduced by Kadimaet al. The model takes into account the variation of the effective charge of the monomer withpH and ionic strength. The neutron scattering results agree well with the predictions of the model.
Paper presented at the I International Conference on Scaling Concepts and Complex Fluids, Copanello, Italy, July 4–8, 1994. 相似文献