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291.
Agarkova Ekaterina A. Borik Mikhail A. Volkova Tatiana V. Kulebyakin Alexey V. Kuritsyna Irina E. Lomonova Elena E. Milovich Filipp O. Myzina Valentina A. Ryabochkina Polina A. Tabachkova Nataliya Yu. 《Journal of Solid State Electrochemistry》2019,23(9):2619-2626
Journal of Solid State Electrochemistry - The crystalline structure, ionic conductivity, and local structure of ZrO2-Gd2O3solid solution crystals have been studied for a wide range of compositions.... 相似文献
292.
Kustov Andrey V. Kudayrova Tatyana V. Antonova Olga A. Smirnova Nataliya L. 《Journal of Thermal Analysis and Calorimetry》2019,138(6):3997-4001
Journal of Thermal Analysis and Calorimetry - This paper focuses on the thermochemical behavior of two derivatives of 1,2,4-triazole which is often considered as a potential synthetic platform to... 相似文献
293.
Dr. Jasmina Grbović Novaković Dr. Nikola Novaković Dr. Sandra Kurko Dr. Sanja Milošević Govedarović Tijana Pantić Dr. Bojana Paskaš Mamula Dr. Katarina Batalović Dr. Jana Radaković Jelena Rmuš Prof. Marina Shelyapina Prof. Nataliya Skryabina Dr. Patricia de Rango Dr. Daniel Fruchart 《Chemphyschem》2019,20(10):1216-1247
This review deals with the destabilization methods for improvement of storage properties of metal hydrides. Both theoretical and experimental approaches were used to point out the influence of various types of defects on structure and stability of hydrides. As a case study, Mg, and Ni based hydrides has been investigated. Theoretical studies, mainly carried out within various implementations of DFT, are a powerful tool to study mostly MgH2 based materials. By providing an insight on metal-hydrogen bonding that governs both thermodynamics and hydrogen kinetics, they allow us to describe phenomena to which experimental methods have a limited access or do not have it at all: to follow the hydrogen sorption reaction on a specific metal surface and hydrogen induced phase transformations, to describe structure of phase boundaries or to explain the impact of defects or various additives on MgH2 stability and hydrogen sorption kinetics. In several cases theoretical calculations reveal themselves as being able to predict new properties of materials, including the ways to modify Mg or MgH2 that would lead to better characteristics in terms of hydrogen storage. The influence of ion irradiation and mechanical milling with and without additives has been discussed. Ion irradiation is the way to introduce a well-defined concentration of defects (Frankel pairs) at the surface and sub-surface layers of a material. Defects at the surface play the main role in sorption reaction since they enhance the dissociation of hydrogen. On the other hand, ball-milling introduce defects through the entire sample volume, refine the structure and thus decrease the path for hydrogen diffusion. Two Severe Plastic Deformation techniques were used to better understand the hydrogenation/dehydrogenation kinetics of Mg- and Mg2Ni-based alloys: Equal-Angular-Channel-Pressing and Fast-Forging. Successive ECAP passes leads to refinement of the microstructure of AZ31 ingots and to instalment therein of high densities of defects. Depending on mode, number and temperature of ECAP passes, the H-sorption kinetics have been improved satisfactorily without any additive for mass H-storage applications considering the relative speed of the shaping procedure. A qualitative understanding of the kinetic advanced principles has been built. Fast-Forging was used for a “quasi-instantaneous” synthesis of Mg/Mg2Ni-based composites. Hydrogenation of the as-received almost bi-phased materials remains rather slow as generally observed elsewhere, whatever are multiple and different techniques used to deliver the composite alloys. However, our preliminary results suggest that a synergic hydrogenation / dehydrogenation process should assist hydrogen transfers from Mg/Mg2Ni on one side to MgH2/Mg2NiH4 on the other side via the rather stable a-Mg2NiH0.3, acting as in-situ catalyser. 相似文献
294.
Irina Petrova Aleksej Gaj Damian Pochiecha Maksim Shcherbina Nataliya N. Makarova 《Liquid crystals》2019,46(1):25-36
Several new comb-like stereoregular cyclolinear methylsiloxane copolymers exhibiting the self-assembling behaviour have been designed and studied. For the resulting macromolecular materials, the chiral mesogenic unit, namely (S)-(–)-4-[1-ethoxycarbonyl)ethoxycarbonyl]phenyl-4′-[11-tetramethyldisiloxyl)-undecenyloxy)-biphenyl-4′-carboxylate, has been used as a side group to assure the mesomorphic behaviour. The mesomorphic and structural properties were studied by the polarising optical microscopy, differential scanning calorimetry and small-/wide-angle X-ray diffraction techniques. The designed copolymers form the orthogonal smectic A* and the tilted smectic C* phases over relatively broad temperature range, down to room temperatures. The obtained results are discussed in order to contribute to better understanding of the molecular architecture–nano-organisation relationship for a specific type of macromolecular system based on the lactic acid derivatives used as a flexible side groups. 相似文献
295.
Katritzky AR Rogovoy BV Cai X Kirichenko N Kovalenko KV 《The Journal of organic chemistry》2004,69(2):309-313
(Benzotriazol-1-yl)carboximidamides were applied for the preparation of polysubstituted acylguanidines and guanylureas. The reaction sequence utilized mild conditions and gave high yields for final compounds and intermediates. The protocol developed allows for variation of the substituents at all positions of the products. 相似文献
296.
A. A. Sysoliatin E. M. Dianov A. I. Konyukhov L. A. Melnikov V. A. Stasyuk 《Laser Physics》2007,17(11):1306-1310
A single-mode fiber with a sinusoidal variation of the core diameter was fabricated. The soliton splitting due to the longitudinal oscillation of the fiber dispersion is demonstrated experimentally. The experimental observations are confirmed through numerical simulations. The periodical modulation of the fiber dispersion can be used for controlling the soliton splitting even under the strong effect of the Raman scattering. 相似文献
297.
Nataliya Sakhnenko Alexander Nerukh Phillip Sewell Trevor Benson 《Optical and Quantum Electronics》2007,39(9):761-771
An investigation of the transformation of whispering gallery modes (WGM) in circular dielectric resonators due to non-uniform
temporal changes of the permittivity is presented. An analytical solution is obtained for the case of an instantaneous refractive
index change within a circular inclusion in the resonator. Analytic-numerical analysis of the obtained solution shows conservation
of the spatial field distribution and a frequency shift. The possibility of field pattern rotation, dependent on the size
and the position of the inclusion, is discussed. 相似文献
298.
A method for estimating the contributions of different factors to the 13C NMR chemical shifts of a ligand has been proposed which is based on elimination of the charge effect and a determination of the combined effect of the remaining factors (the coordination effect). This enabled the authors to establish a relationship between the 13C NMR data and the chemical properties of cyclopentadienyl metal compounds. 相似文献
299.
Xuewen Hua Wutao Mao Zhijin Fan Xiaotian Ji Fengyun Li Guangning Zong Haibin Song Kalinina Tatiana Yury Yu. Morzherin Nataliya P. Belskaya Vasiliy A. Bakulev 《Journal of heterocyclic chemistry》2016,53(3):865-875
Three series of new anthranilic diamide derivatives containing sulfide, N‐cyanomethylsulfilimine, and N‐cyanomethylsulfoximine groups were designed and synthesized by combining the active substructures of anthranilic diamides and sulfoxaflor. The structures of all newly synthesized compounds were confirmed by IR and 1H/13C‐NMR, and some of them were confirmed by elemental analysis or HRMS too. The synthesized compounds were screened for their insecticidal and fungicidal activities. Bioasssay results indicated that some of the synthesized compounds possessed certain degrees of insecticidal activity against Mythimna separata. However, some compounds exhibited good fungicidal activity against Sclerotinia sclerotiorum. 相似文献
300.
Valery N Charushin Nataliya N MochulskayaAnatoly A Andreiko Vera I FilyakovaMikhail I Kodess Oleg N Chupakhin 《Tetrahedron letters》2003,44(11):2421-2424
5,6-Unsubstituted-3-aryl-1,2,4-triazines were found to react with aminovinyl ketones and aminovinyl esters in acetic anhydride to form derivatives of 3a,4,7,7a-tetrahydro-1H-pyrrolo[3,2-e]1,2,4-triazines in good yields. 相似文献