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排序方式: 共有294条查询结果,搜索用时 15 毫秒
61.
62.
N. Guskos J. Typek V. Likodimos H. Fuks M. Wabia J. Walczak E. Lukaszczyk-Tomaszewicz 《Applied magnetic resonance》1998,14(2-3):403-408
The temperature dependence of the EPR spectra of the recently discovered Ag6S3O4 phase in the Ag-O-S system prepared by two methods, the known method of co-precipitation from aqueous solution and a new method depending on the interaction of Ag2S and Ag2SO4 solid reagents, has been investigated. No EPR spectra were observed at room temperature, while at liquid helium temperature a number of EPR spectra have been recorded, which disappeared upon increasing temperature up to liquid nitrogen temperature. The sample obtained by the co-precipitation method revealed an intense, rich EPR spectrum that has been tentatively interpreted assuming the presence of at least two different Ag2+ ion complexes, one monomer resulting in an intense anisotropic, rhombic EPR powder pattern with g1 = 1.93(1), g2 = 2.025(3), g3 = 2.094(5), hyperfine constants A1 = = A2 = 60(5) · 10?4 cm?1,A 3 = 90(5) · 10?4 cm?1 and one dimer EPR pattern presumably involving a pair of Ag2+ ions with internuclear separation of 4.3 Å. However, the presence of larger clusters could not be excluded. On the other hand, the sample obtained by a solid state reaction method has given rise to two rather weak EPR lines centered at geff = 2.105(3) and geff = 4.213(3), respectively. 相似文献
63.
Alexander A. Kokhanovsky Vladimir P. Budak Celine Cornet Minzheng Duan Claudia Emde Iosif L. Katsev Dmitriy A. Klyukov Sergey V. Korkin L. C-Labonnote Bernhard Mayer Qilong Min Teruyuki Nakajima Yoshifumi Ota Alexander S. Prikhach Vladimir V. Rozanov Tatsuya Yokota Eleonora P. Zege 《Journal of Quantitative Spectroscopy & Radiative Transfer》2010,111(12-13):1931-1946
In this paper seven vector radiative transfer codes are inter-compared for the case of underlying black surface. They include three techniques based on the discrete ordinate method (DOM), two Monte-Carlo methods, the successive orders scattering method, and a modified doubling-adding technique. It was found that all codes give very similar results. Therefore, we were able to produce benchmark results for the Stokes parameters both for reflected and transmitted light in the cases of molecular, aerosol and cloudy multiply scattering media. It was assumed that the single scattering albedo is equal to one. Benchmark results have been provided by several studies before, including Coulson et al. [22], Garcia and Siewert [7], [8], Wauben and Hovenier [10], and Natraj et al. [11] among others. However, the case of the elongated phase functions such as for a cloud and with a high angular resolution is presented here for the first time. Also in difference with other studies, we make inter-comparisons using several codes for the same input dataset, which enables us to quantify the corresponding errors more accurately. 相似文献
64.
Emil Burzo Istvan Balasz Iosif Deac Romulus Tetean 《Journal of magnetism and magnetic materials》2010,322(9-12):1109-1112
Magnetic properties and magnetocaloric effects were studied in (GdxY1?x)3Co11B4 ferrimagnetic compounds. Rather high values of the entropy changes were shown in large temperature ranges. The ΔS values were correlated with high temperature dependences of resultant magnetizations determined mainly by the gadolinium sublattice one. Large relative cooling power was also shown. 相似文献
65.
L. Fuks E. Anuszewska H. Kruszewska A. Krówczyński J. Dudek N. Sadlej-Sosnowska 《Transition Metal Chemistry》2010,35(6):639-647
Platinum(II) complexes with 1-(2-oxolanylmethyl)-2-thiourea, 1-(2-thiolanylmethyl)-2-thiourea and 1-(2-selenolanylmethyl)-2-thiourea were synthesized in order to compare their cytotoxic activities with those of the free thioureas. Their equilibrium geometries and bonding energies in the gas phase and in solution were calculated using density functional theory at the MPW1PW/LanL2DZ level. The IR spectra of the complexes and their free ligands were compared. Stability of the complexes in 0.9% saline aqueous solution was tested by means of HPLC. The cytotoxic activities of the species against five human cell lines were evaluated, as well as the antimicrobial activities against twelve bacterial strains. 相似文献
66.
É. B. Abubakirov A. N. Denisenko N. F. Kovalev E. A. Kopelovich A. V. Savel’ev E. I. Soluyanov M. I. Fuks V. V. Yastrebov 《Technical Physics》1999,44(11):1356-1359
A new version of the relativistic backward wave oscillator (BWO) is proposed and investigated experimentally, where the cutoff
(for the working mode mode) taper at the cathode end is replaced by a selective Bragg-type mode converter. In the experimental
BWO model, which operates in the three-centimeter range and is equipped with a mode converter based on a slightly corrugated
waveguide, a radiated power of 700 MW in pulses of duration up to 100 ns with an output spatial structure similar to a Gaussian
wave beam is obtained at an accelerating potential of 0.8 MV and a focusing magnetic field of 7 kOe.
Zh. Tekh. Fiz. 69, 102–105 (November 1999) 相似文献
67.
The amidinoethylation of alcohols by their Michael-type addition to propenamidines takes place without the need of a basic catalyst. The effect of the basicity of the amidine and the nature of the alcohol on the course of the reaction is discussed. The reaction is assumed to proceed by an SNi' mechanism. 相似文献
68.
L. Fuks E. Gniazdowska P. Kozminski J. Mieczkowski 《Journal of Radioanalytical and Nuclear Chemistry》2012,292(1):255-259
Technetium(I) tricarbonyl complexes may form with the pyridine aldehyde thiosemicarbazones (TSCs), in which chelating ligand is bound tri- or bidentately. Intend of the presented work was to check, if labeling the N-heterocyclic TSCs with tricarbonyl [99mTc]-technetium(I) may lead to formation of the complexes suitable for the radiopharmaceutical purposes. Syntheses of the complexes were provided in the conditions analogous to those performed in the nuclear medicine laboratories. Main physicochemical properties of the complexes important in the medicinal chemistry were studied. Relevant results of the numerical calculations remain in fair agreement with these properties. 相似文献
69.
C. Beşliu A. Jipa D. Argintaru C. Argintaru R. Zaharia J. Gabriel Rican M. Iosif 《The European Physical Journal A - Hadrons and Nuclei》1998,1(1):65-75
The problem of the nuclear matter jets in nucleus-nucleus collisions at 4.5 A GeV/c is discussed. The global analysis of
experimental data, namely the sphericity tensor, is used to evidence such jets. The experimental results are compared with
those obtained in the same collisions for hydrodynamic flow and thrust. The experiments have been performed in the frame of
the SKM 200 Collaboration from JINR Dubna.
Received: 20 March 1997 / Revised version: 20 July 1997 相似文献
70.