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561.
L. Yu. Ukhin L. G. Kuz’mina T. N. Gribanov L. V. Belousova Zh. I. Orlova 《Russian Chemical Bulletin》2008,57(11):2340-2348
A modified procedure was developed for the synthesis of 5,6,7,8,13,13a-hexahydrophthalazino[1,2-b]quinazoline-5,8-dione and 6-amino-5,6,6a,11-tetrahydroisoindolo[2,1-a]quinazoline-5,11-dione from o-formylbenzoic acid and anthranilic acid hydrazide. The mechanism of the transformation is suggested, some reactions were
studied, and new derivatives of these compounds were synthesized. Anthranilic acid hydrazide was used in the novel synthesis
of 5-substituted phthalazino[1,2-b]quinazolin-8-one derivatives. The possible reaction mechanism is discussed. 5,6,7,8-Tetrahydrophthalazino[1,2-b]quinazoline-5,8-dione and 5-phenylphthalazino[2,1-b]quinazolin-8-one were studied by X-ray diffraction. 相似文献
562.
G. V. Kuznetsov D. V. Feoktistov E. G. Orlova I. Yu. Zykov K. A. Batishcheva 《Thermophysics and Aeromechanics》2018,25(2):237-244
The article presents the experimental dependences of a macro-contact angle and the diameter of a distilled water drop spreading over solid microstructured surface on surface average roughness (Ra) and fluid flow rate (G). It has been found that at changing G from 0.005 to 0.02 ml/s, the contact angle decreases, and at a liquid flow rate over 0.02 ml/s, it increases. With small values of G (0.005?0.01 ml/s), the drop diameter grows throughout the spreading process. In the range of G from 0.02 to 0.16 ml/s at the final stage of spreading, the contact line pinning, i.e., the diam-eter constancy, has been detected. The hypothesis about the mechanism of the pinning process has been formulated: it is due to the zero sum of all forces acting on the drop (inertia, viscosity, friction, gravity, and surface tension). 相似文献
563.
A. O. Orlova V. G. Maslov A. V. Baranov I. Gounko S. Byrne 《Optics and Spectroscopy》2008,105(5):726-731
The spectral-luminescence manifestations of the formation of quantum dot (QD)-phthalocyanine complexes as a result of electrostatic interaction have been investigated. Effective QD luminescence quenching has been found in complexes of this type. The luminescence of the molecules associated in complexes with QDs is also partially quenched. A mathematical model of the formation of QD-organic molecule complexes is proposed. 相似文献
564.
A. K. Visheratina A. Loudon V. A. Kuznetsova A. O. Orlova Yu. K. Gun’ko A. V. Baranov A. V. Fedorov 《Optics and Spectroscopy》2018,124(1):94-97
An algorithm for wavefront calculation of ordinary and extraordinary waves after propagation through hemispherical components made of a uniaxial crystal is developed. The influence of frequency dispersion of n о and n e , as well as change in the direction of the optic axis of the crystal, on extraordinary wavefront in hemispheres made of from leuco-sapphire and a plastically deformed analog thereof is determined. 相似文献
565.
E. P. Kolesova A. O. Orlova V. G. Maslov Yu. K. Gun’ko O. Cleary A. V. Baranov A. V. Fedorov 《Optics and Spectroscopy》2018,125(1):99-103
Multilayer hybrid nanostructures based on nanoparticles of TiO2 and CdSe/ZnS semiconductor quantum dots were formed. Generation of active forms of oxygen by hybrid nanostructures under visible-light irradiation is demonstrated to take place, which is indicative of efficient photoinduced electron transfer from quantum dots to titanium-oxide nanoparticles contained in the hybrid nanostructures. 相似文献
566.
Polycrystalline samples of PbLn 4Mo3O16 (Ln = La, Pr, Nd, or Sm), CdLn 4Mo3O16 (Ln = La, Nd, Sm, Eu, or Tm), and PbLa4–xNdxMo3O16 (0 ≤ x ≤ 3) with the cubic fluorite-like structure and sp. gr. Pn n have been obtained by solid-phase synthesis in air. The specific conductivity of lead compounds is established to reach 10–2 S/cm (which is an order of magnitude higher than that for cadmium compounds). The conductivity value is shown to reach a maximum at a concentration ratio of rare-earth elements of Nd: La = 1: 1. 相似文献
567.
V. V. Shpeizman T. S. Orlova A. A. Spitsyn D. A. Ponomarev N. I. Bogdanovich J. Martinez-Fernández 《Physics of the Solid State》2017,59(1):114-119
The effect of activation on the size, specific volume, and surface area of pores in a monolithic biomorphic material obtained by carbonization of beech wood is studied. It is shown that under optimal activation mode with a steam heated to 970°C, the total pore volume and surface, determined by adsorption curves, increased by 20 and 18 times, respectively. With the use of high-precision interferometric procedure, strain curves are obtained under uniaxial compression with a stepwise loading, and the strain rate is measured with a step of moving of 325 nm for activated and nonactivated samples. Despite an increase in porosity, the strength and maximum deformation of the samples do not decrease. The behavior of the strain rate jumps is analyzed in the micro- and nanometer range. It is shown that the maximum size of the micrometer jumps (4 μm) correlates well with the average size of the possible strain area in the samples (the average distance between the pores of small size), and the minimum dimensions of the strain jumps are close to the size of mesopores. Assessment of the strain change and its rate upon activation indicates that the effect of activation on the strain and strength characteristics is defined by nanometer defects, the most likely of which are microand mesopores. 相似文献
568.
A. M. Mavlyutov T. A. Latynina M. Yu. Murashkin R. Z. Valiev T. S. Orlova 《Physics of the Solid State》2017,59(10):1970-1977
The influence of annealing on the microstructure and mechanical properties of ultrafine-grained (UFG) commercially pure aluminum preliminarily subjected to severe plastic deformation by high pressure torsion has been studied. It is found that annealing of the UFG samples in the temperature range 363–473 K for 1 h leads to increases in the conventional yield strength and ultimate tensile strength, which attained maximum values (50 and 30%, respectively) after annealing at 423 K. A key role of nonequilibrium high-angle grain boundaries in the strengthening effect of UFG-Al due to annealing is discussed. The increase in the strength of UFG-Al is accompanied by a significant decrease in its ductility. A new approach of increasing the ductility of UFG-Al with retaining a high strength is proposed. It is an introduction of additional dislocation density to a UFG structure relaxed by annealing. 相似文献
569.
A. Abd-Elhafiez V. Sh. Navotny V. V. Uzhinskii G. I. Orlova M. M. Chernyavski 《Physics of Atomic Nuclei》2001,64(1):62-67
Experimental data on the multifragmentation of residual nuclei produced in the krypton interactions with photoemulsion nuclei at 0.9 GeV per projectile nucleon are presented and compared with similar data on fragmentation from experiments where gold nuclei of energy 10.7 GeV per nucleon appear as projectiles. It is shown for the first time that there exist two modes of nuclear multifragmentation, those where less (first mode) or more (second mode) than half of nucleons are knocked out of the incident nucleus. Residual nuclei that have close masses and which are produced in various reactions accompanied by the knock-on of more than half of nucleons of the initial nucleus fragment in nearly the same way. In addition, evidence for a radial flux of spectator fragments is obtained for the first time in the decay of residual nuclei of krypton projectiles. 相似文献
570.
Measurements of the diffuse X-ray scattering are performed from the (110) plane in V3Si single crystal at different temperatures from 300 to 8 K. Contours of equal diffuse scattering intensity are drawn over the 440 node in the (001) and (111) sections. The temperature dependence and the anisotropy of the thermal diffuse scattering intensity distribution for this compound are analysed. 相似文献