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941.
N. Barrier P. Gall P. Gougeon 《Acta Crystallographica. Section C, Structural Chemistry》2007,63(11):i102-i104
Trisamarium molybdenum heptaoxide, Sm3MoO7, is isomorphous with Ln3MoO7 (Ln = La and Pr). The crystal structure consists of chains of corner‐linked MoO6 octahedra running parallel to the b axis and separated from each other by seven‐ or eight‐coordinate Sm–O polyhedra. In contrast to La3MoO7 and Pr3MoO7, a splitting of one Sm site into two positions is observed. 相似文献
942.
In homogeneous negative phase velocity media, the Doppler and Cherenkov-Vavilov effects and the refraction and pressure of light are anomalous: they are inverse with respect to the corresponding effects in conventional media. Using the geometrical optics approximation, it is shown that the optical Magnus effect in inhomogeneous negative phase velocity media is also anomalous. The effect is demonstrated by considering a metamaterial consisting of parallel amorphous ferromagnetic microwires in a magnetic field. The metamaterial proves to be a left-handed one in the realistic region of the electromagnetic spectrum. The optical properties of such a left-handed medium can be controlled by the external magnetic field. 相似文献
943.
L. P. Eksperiandova A. I. Fedorov Ya. N. Makarovskaya 《Journal of Analytical Chemistry》2007,62(12):1163-1166
A series of quasi-solid emitters is proposed for the X-ray fluorescence determination of bromine in different bromine-containing compounds. It is shown that sucrose-based glasses are the best emitters for analyzing alkali solutions of halogenated organic compounds, saccharose-based glasses and polymer films are best for analyzing powder samples, and organic gels offer most promise for analyzing liquid (at normal conditions) samples. It is noted that the proposed method can expand the possibilities of commercially produced element analyzers, which are currently intended for determining only C, H, O, N, and S in organic compounds and cannot be used for determining halogens. 相似文献
944.
V. P. Antonovich I. V. Stoyanova N. A. Chivireva E. V. Timukhin V. F. Zinchenko N. P. Efryushina 《Journal of Analytical Chemistry》2007,62(3):238-244
Diffuse reflectance spectroscopy in the UV, visible, and near-IR regions is found to allow the detection and identification of lanthanide oxides, fluorides, sulfides, and sulfofluorides without decomposing and dissolving samples. A nondestructive method for the detection and quantitative determination of more than 1 wt % of Eu(II) in the corresponding fluorides is proposed. 相似文献
945.
946.
I. A. Belogorokhov M. N. Martyshov E. V. Tikhonov M. O. Breusova V. E. Pushkarev P. A. Forsh A. V. Zoteev L. G. Tomilova D. R. Khokhlov 《JETP Letters》2007,85(12):655-657
The Raman spectra have been obtained and the temperature dependence of the conductivity of organic semiconductor structures based on butyl-substituted erbium monophthalocyanine and erbium triphthalocyanine has been studied. It has been found experimentally that the activation energy decreases dramatically and the Raman spectra exhibits four new peaks in the region of large Raman shifts as the molecular structure of the samples becomes more complicated. 相似文献
947.
We present a way of introducing joint distibution function and its marginal distribution functions for non-compatible observables.
Each such marginal distribution function has the property of commutativity. Models based on this approach can be used to better
explain some classical phenomena in stochastic processes. 相似文献
948.
A multiparameter boundary-value problem of fresh infiltration water seepage in a drained fringe above quiescent saline water is solved in the direct statement and studied in detail. 相似文献
949.
950.
Starting with the unification hypothesis of mixings of quarks and leptons and small quark-like mixings at the see-saw scale,
we find that two large mixings for νe —νx03BC; andv
μ—v
τ at the weak scale are obtained as a result of renormalization group evolution and radiative magnification if the three neutrinos
are quasi degenerate in masses and possess the same CP parity. We also find thatU
e3
remains small and well within the CHOOZ-Palo Verde bound since the correspondingV
ub
for CKM mixing is very small. Several testable pedictions are pointed out. 相似文献