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41.
42.
Kaoru Toyoda 《International journal of quantum chemistry》1988,34(6):489-503
Here is presented a method to determine the consistent ground state (CGS ) which satisfies the so-called killer condition for the excitation operator. This method may be called an extended application of the procedure employed by Weiner and Goscinski in deriving the random phase approximation (RPA ) vacuum. The RPA vacuum is derived by solving the recurrence formula of the configuration coefficients of a multiconfigurational state vector. The role of boson approximation to the primitive p-h excitation operator is also investigated and by using the present formalism the cluster-expansion-type CGS is derived as the RPA vacuum under the boson approximation. Inclusion of the effects of a higher RPA in the CGS leads to the simultaneous equations of the configuration coefficients of the CGS . In including the effect of the second RPA , only the symmetry-broken CGS can exist. When the third RPA effect is involved instead of the second RPA , there can be a symmetry-adapted CGS , in which the picture of electron pairs acquired in the standard RPA vacuum is modified. Thus the exact CGS vectors are analytically obtained in the case of simple model systems of two or four electrons. 相似文献
43.
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45.
A convenient synthesis of 1,4-benzodiazepines starting from secondary-2-aminobenzhydrols, which are easily obtained from secondary anilines and benzaldehydes, is described. 7-Nitro-1-methyl-1,4-benzodiazepine 1d can be formed from 5-nitro-2-methylaminomethylacylaminobenzo-phenone 10b and c by using ammonium carbonate instead of ammonia, which gives only the Smiles-rearranged product 11 . 相似文献
46.
Kumondai K Toyoda M Ishihara M Katakuse I Takeuchi T Ikeda M Iwamoto K 《The Journal of chemical physics》2005,123(2):24314
The reaction mechanisms of silver trimer cation, Ag3+, with 12-crown-4 (12C4) were studied experimentally and theoretically. Using a cylindrical ion trap time-of-flight mass spectrometer, gas-phase ion/molecule reactions of Ag3+ with 12C4 were observed. Metal-ligand complexes of [Ag(12C4)]+, [Ag3(12C4)]+ and [Ag3(12C4)2]+, and of [Ag(12C4)2]+ and [Ag3(12C4)3]+, were observed as the reaction intermediates and terminal products, respectively. The formations of the [Ag12C4]+ and [Ag(12C4)2]+ complexes indicated that the neutral dimer (Ag2) had been eliminated from the trimer cation. From the results of ab initio calculations at the HF/LanL2DZ level of theory and the experiments, it is suggested that three 12C4 molecules can attach to Ag3+ through consecutive reactions and that neutral Ag2 can be easily eliminated from [Ag3(12C4)]+. 相似文献
47.
48.
The retarded transverse current-current response functions of an ideal two-dimensional electron gas at zero temperature are calculated. Introducing a new approximation scheme which allows one to take account of the reaction of the electromagnetic field to the induced current, i.e. the influence of the electronic induced current on the dynamics of the electromagnetic field, within the framework of the conventional linear response theory in a self-consistent way, a possible form of the dispersion relation for the transverse plasmon in the system is obtained. It is found that the energy of the transverse plasmon has a gap at k=0, if the thickness of the system is finite, in contrast to the longitudinal case. 相似文献
49.
This paper describes use of a novel glass bead-based immobilized-enzyme micro column for simple and swift on-line protein
digestion then peptide separation by reversed-phase HPLC. The inexpensive and easily made immobilized-enzyme micro column
was prepared from aminopropyl controlled-pore glass that was reacted first with glutaraldehyde then with trypsin in the presence
of phosphate buffer. Tryptic digestion of bovine serum albumin (BSA) was achieved simply by passing pretreated protein solution
through the laboratory made immobilized-trypsin column; the tryptic fragments were then separated by reversed-phase HPLC.
The peptide separation was found to be identical to separation of a sample which had undergone conventional enzymatic protein
digestion in solution. Digestion of BSA by the immobilized-trypsin column decreased with increasing flow rate of the solution
through the column, and 1.0 μL min−1 was found to be the optimum flow rate for on-line protein digestion with our system. It was also found that the sample required
pretreatment with urea before injection, because of a change in the properties of the protein in the presence of urea, and
the immobilized-trypsin column lost its function in the presence of acetonitrile. This on-line proteomics system enables simple
and rapid protein digestion and was successfully applied to partially micro two-dimensional (2D) chromatographic separation
of proteins. 相似文献
50.
Sylwia Mozia Ewa Borowiak-Paleń Barbara Grzmil Masahiro Toyoda Antoni W. Morawski 《Journal of Physics and Chemistry of Solids》2010,71(3):263-26
Titanate nanotubes (TNTs) were prepared from TiO2 P25 via hydrothermal method. The reaction temperature was 130 or 140 °C and the reaction time was 24 or 48 h. The samples were characterized by transmission electron microscopy, X-ray diffraction, thermogravimetry and N2 adsorption as well as Raman, FTIR-DRS and UV-vis/DR spectroscopy. The obtained samples exhibited similar properties, regardless of the preparation temperature and time. The most notable difference between properties of TNTs prepared under different conditions was observed in case of BET surface area, which was increasing from 386 to 478 m2/g along with increasing the reaction time and temperature. Based on TEM, XRD and TG measurements we have suggested that the structure of TNTs was H2Ti2O4(OH)2. The TEM and Raman spectroscopy measurements showed that the obtained products contained also low amount of anatase phase. The TNTs exhibited no photoactivity towards degradation of model azo dye Acid Red 18. However, TNTs were successfully applied for photocatalytic generation of CH4 and H2 in a solution of acetic acid. The amount of methane produced with application of TNTs synthesized at 140 °C was about 2.5 times higher than that generated with use of TiO2 P25. To the best of our knowledge this is a first report on the photocatalytic generation of hydrocarbons using TNTs in the current state of the art. 相似文献