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51.
Valerio Magnasco Massimo Ottonelli Giuseppe Figari Marina Rui Camilla Costa 《Journal of Molecular Structure》1998,430(1-3):231-239
The real spherical tensor theory of long-range intermolecular coefficients developed in previous papers is applied to derive explicit formulae for the first three dispersion coefficients for like centrosymmetric linear molecules. The expansion of angle-dependent coefficients in associated Legendre polynomials allows one to identify the isotropic and anisotropic components of the dispersion interaction in terms of London dispersion constants, the treatment of higher coefficients being simplified by the coupling of the elementary (l, l′)-polarizations to resultant angular momenta LA and LB onto each molecule. The contributions from all coupling schemes are given explicitly for C6, C8, C10, and numerical results are presented for H2-H2 using two-term reduced spectra values from the Kaiserlautern group. 相似文献
52.
Synthesis of 1-(4-substituted)benzyl-6-hydroxyisoquinolines with potential activity on NA+,K+-atpase
Alberto Cerri Paola Mauri Marina Mauro Piero Melloni 《Journal of heterocyclic chemistry》1993,30(6):1581-1591
The synthesis of 1-(4-substituted)benzyl-6-hydroxyisoquinolines, to be evaluated in the displacement of the specific 3H-ouabain binding to Na+,K+-ATPase, is described. The key step involved a cyclization to the isoquinoline ring under Pictet-Gams conditions which was best performed with the 6-hydroxy group protected as the benzyl ether. When an unsaturated ester group was present in position 4 of the 1-benzyl group, this was best introduced before the cyclization step, since the IIeck reaction on 1-(4-bromobenzyl)-6-hydroxyisoquinoline ( 8 ) with acrylic acid derivatives was not successful in all cases. 相似文献
53.
Penna Thereza Christina Vessoni Marques Marcelo Machoshvili Irena A. Ishii Marina 《Applied biochemistry and biotechnology》2002,98(1-9):539-551
Large-volume parenteral solutions were submitted to heat treatments after being inoculated with Bacillus stearothermophilus ATCC 7953 (T
r
=121°C) and Bacillus subtilis ATCC 9372 (T
r
=104.5°C) spores. The average decimal reduction time for B. stearothermophilus ranged from a D
121°C value of 1.31 to 3.14 min, in glucophysiologic and Ringer’s solutions respectively. For B. subtilis, D
104.5°C value increased from 0.69 to 1.37 min, in Ringer’s (pH=5.91) and 50% glucose (pH 3.05) solutions respectively. The z value ranged from 7.95°C (20% mannitol solution) to 13.14°C (50% glucose solution), corresponding to an activation energy
(Ea) of 81.48 and 49.30 kcal/mol, respectively. 相似文献
54.
A Lorentz-invariant gauge theory for massive fermions on R × S
3
spacetime is built up. Using the symmetry of S
3,we obtain Dirac-type equation and derive the expression of the fermionic propagator. Finally, starting from the SU(N) gauge-invariant Lagrangian, we obtain the set of Dirac-Yang-Mills equations on R × S
3
spacetime, pointing out major differences from the Minkowskian case. 相似文献
55.
A. Weidinger J. Erxmeyer H. Glückler Ch. Niedermayer O. Laforsch J. Groß M. Mehring 《Hyperfine Interactions》1994,86(1):609-614
Hydrogenated YBa2Cu3O7 with [H]/cell=2.0 was studied by X-ray diffraction, SR and1H-NMR. For the first time, the hydride phase (16% larger c-axis) known from thin film experiments was seen in a bulk sample. A comparison of the SR and NMR results shows that the 15 mT site (2 MHz in SR) is the stable position for the proton and muon. The three other muon sites (4 MHz line and two exponentially decaying components) are metastable. 相似文献
56.
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59.
Mg(AlH(4))(2) was produced as a nanocrystalline powder by metathesis of NaAlH(4) and MgCl(2). Starting with a structure estimation which was developed from an evaluation of FTIR data and comparison of structural properties of two solvent adducts, quantum chemical calculations were performed on the density functional theory (DFT) level. The calculated atomic positions were used to simulate an X-ray powder diffraction pattern, based on a trigonal unit cell. The simulated pattern was congruent to experimental data. Thus, magnesium alanate exhibits a CdI(2) layer structure, the layers being formed by Mg atoms occupying the Cd sites and AlH(4) tedrahedra occupying the sites of the iodine atoms in CdI(2). 相似文献
60.
Thereza Christina Vessoni Penna Marina Ishii Adalberto Pessoa Junior Laura de Oliveira Nascimento Luciana Cambricoli de Souza Olivia Cholewa 《Applied biochemistry and biotechnology》2004,114(1-3):453-468
To determine the influence of various culture conditions, transformed cells of Escherichia coli expressing recombinant green fluorescent protein (GFPuv) were grown in nine cultures with four variable conditions (storage
of inoculated broth at 4°C prior to incubation, agitation speed, isopropyl-β-d-thiogalactopyranoside [IPTG] concentration, and induction time). The pelleted cells were resuspended in extraction buffer
and subjected to the three-phase partitioning (TPP) extraction method. To determine the most appropriate purification resin,
protein extracts were eluted through one of four types of HiTrap hydrophobic interaction chromatography (HIC) columns prepacked
with methyl, butyl, octyl, or phenyl resins and analyzed further on a 12% sodium dodecylsulfatepolyacrylamidegel. With Coomassie
staining, a single band between 27 (standard GFPuv) and 29 kDa (molecular weight standard) was visualized for every HIC column
sample. TPP extraction with HIC elution provided about 90% of the GFPuv recovered and eight-fold GFPuv enrichment related
to the specific mass. Rotary speed and IPTG concentration showed, respectively, greater negative and positive influences on
GFPuv expression at the beginning of the logarithmic phase for the set culture conditions (37°C, 24-h incubation). 相似文献