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31.
Nanoaggregation of the thermally stable bis(2-hydroxy-9(10),16(17),23(24)-tri-tert-butylphthalocyanine) of J-type was observed by the field emission scanning electron microscopy (FE-SEM). Ordered phases, represented as threads composed of about 200 nm diameter circles were discovered, unlike the parent dimeric magnesium complex, in which similar circles combine together to give visually distinguishable zones with widths of about 600 nm and the same distance between them. 相似文献
32.
Larisa Petrovna Demyanova Viaseslav S. Rimkevich Alexandre S. Buynovskiy 《Journal of fluorine chemistry》2011,132(12):1067-1071
A method of elaboration of nanometric amorphous silica is proposed using a rational processing of quartz-based ores with the help of a fluorination method. The different steps of the process are described, including the kinetics of the interaction mechanism of ammonium bifluoride with the initial raw materials, the sublimation of ammonium fluorosilicate and the formation of nanometric amorphous silica. Rate constants and activation energy of the chemical reactions are calculated. 相似文献
33.
34.
A method is presented for the coherent control of two-level systems when T2 relaxation is significant. The Bloch equations are rewritten as an equation of motion of the stereographic projection, Gamma, of the spin vector. This allows a Schur-type iteration used for the design of shaped pulses in magnetic resonance and coherent optics to be extended to include the effect of T2. In general, the effect of T2 on Gamma cannot be completely compensated for, although in practice it can be to a high degree. An example is presented of a driving field that produces a coherent superposition (no on-diagonal elements of the density matrix) over a chosen band of frequencies, in the presence of relaxation. 相似文献
35.
Marija Dimitrijević Larisa Jonke Lutz Möller Efrossini Tsouchnika Julius Wess Michael Wohlgenannt 《Czechoslovak Journal of Physics》2004,54(11):1243-1248
A general formalism is developed, that allows the construction of field theory on quantum spaces which are deformations of ordinary spacetime. The symmetry group of spacetime is replaced by a quantum group. This formalism is demonstrated for the -deformed Poincaré algebra and its quantum space. The algebraic setting is mapped to the algebra of functions of commuting variables with a suitable -product. Fields are elements of this function algebra. As an example, the Klein-Gordon equation is defined and derived from an action. 相似文献
36.
37.
Konstantin A. Kozhanov Michael P. Bubnov Nina N. Vavilina Larisa Yu. Efremova Georgy K. Fukin Vladimir K. Cherkasov Gleb A. Abakumov 《Polyhedron》2009,28(13):2555-2558
Structural study of dialkyl (PCP)-pincer o-semiquinonato nickel complexes indicated sloped relative positions of bi- and tri-dentate ligands. It became bright confirmation of propositions made on the base of their EPR spectra followed by molecular modelling. 相似文献
38.
Eiji Kobayashi Larisa S. Plashnitsa Takayuki Doi Shigeto Okada Jun-ichi Yamaki 《Electrochemistry communications》2010,12(7):894-896
All-solid-state phosphate symmetric cells using Li3V2(PO4)3 for both the positive and negative electrodes with the phosphate Li1.5Al0.5Ge1.5(PO4)3 as the solid electrolyte were proposed. Amorphous Li1.5Al0.5Ge1.5(PO4)3 was added into the electrode to increase the interface area between the active materials and the electrolyte. Any other phases were not formed at the electrode/electrolyte interface even after hot pressing at 600 °C. The discharge capacity was 92 mAh g? 1 at 22 µA cm? 2 at 80 °C, and 38 mAh g? 1 at 25 °C, respectively. Symmetric cell configuration leads to simplify the fabrication process for all-solid-state batteries and will reduce manufacturing costs. 相似文献
39.
Leonid G. Voskressensky Larisa N. KulikovaSergey V. Gozun Victor N. KhrustalevTatiana N. Borisova Anna V. ListratovaMaxim V. Ovcharov Alexey V. Varlamov 《Tetrahedron letters》2011,52(32):4189-4191
The first synthesis of tetrahydrochromeno[4,3-d]azocines via an alkyne-induced expansion reaction is described. 相似文献
40.
Rodica Olar Mihaela Badea Dana Marinescu Larisa Calu Cristina Bucur 《Journal of Thermal Analysis and Calorimetry》2011,105(2):571-575
Novel complexes of type [M2LCl4]·nH2O ((1) M:Ni, n = 5; (2) M:Cu, n = 0 and (3) M:Zn, n = 2; L: ligand resulted from 1,2-phenylenediamine, 3,6-diazaoctane-1,8-diamine and formaldehyde template condensation) were
synthesised and characterised. The features of complexes have been assigned from microanalytical, IR and UV–Vis data. The
thermal analyses have evidenced the thermal intervals of stability and also the thermodynamic effects that accompany them.
Processes as water or hydrochloric acid elimination as well as oxidative degradation of the organic ligand were observed.
Complexes display a different thermal behaviour as result of dissimilar chemical interaction of metal ions with chloride anions.
The final product of decomposition was metal(II) oxide as powder X-ray diffraction indicated. 相似文献