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201.
Ahmad Poursattar Marjani ;Bayram Parsa Habashi ;Hojjatollah Rahchamani ;Jabbar Khalafy ;Alireza Dadrass ;Hooman Yaghoobnejad Asl 《结构化学》2014,(10):1460-1466
A new series of quinoxalinophenazine derivatives were synthesized in good yields by the reaction of 2,3-dibromonaphthalene-1,4-dione with different aryl-1,2-diamines in DMF as solvent at 120~130℃ or under reflux conditions. 3,12-dimethylbenzo[a]quinoxalino[2,3-c] phenazine with bidentate character reacts with mercury(II) bromide to give suitable crystals. All products were confirmed by IR, 1H and 13 C NMR, and the metal complex by single-crystal X-ray method. The crystal(C24H16Br2HgN4, Mr = 720.82) belongs to the triclinic system, space group P1 with a = 10.186(6), b = 10.421(6), c = 11.470(7) , α = 98.670(7), β = 95.069(7), γ = 109.831(7)o, V = 1119.4(12) 3, Z = 2, Dc = 2.139 Mg/m3, μ = 10.46 mm-1, F(000) = 676, R = 0.043 and wR = 0.115 for 3982 observed reflections with I 2σ(I). 相似文献
202.
The grain boundary groove shapes for equilibrated solid neopentylglycol (NPG) solution (NPG–3 mol% D-camphor) in equilibrium with the NPG–DC eutectic liquid (NPG–36.1 mol% D-camphor) have been directly observed using a horizontal linear temperature gradient apparatus. From the observed grain boundary groove shapes, the Gibbs–Thomson coefficient (Г), solid–liquid interfacial energy (σSL) of NPG solid solution have been determined to be (7.5±0.7)×10?8 K m and (8.1±1.2)×10?3 J m?2, respectively. The Gibbs–Thomson coefficient versus TmΩ1/3, where Ω is the volume per atom was also plotted by linear regression for some organic transparent materials and the average value of coefficient (τ) for nonmetallic materials was obtained to be 0.32 from graph of the Gibbs–Thomson coefficient versus TmΩ1/3. The grain boundary energy of solid NPG solution phase has been determined to be (14.6±2.3)×10?3 J m?2 from the observed grain boundary groove shapes. The ratio of thermal conductivity of equilibrated eutectic liquid to thermal conductivity of solid NPG solution was also measured to be 0.80. 相似文献
203.
204.
Ida S Araki K Unal U Izawa K Altuntasoglu O Ogata C Matsumoto Y 《Chemical communications (Cambridge, England)》2006,(34):3619-3621
Multilayer oxide films consisting of a TiO-Eu3+-TiO-Tb3+-NbO-Tb3+-NbO-Eu3+ unit which was prepared by the layer-by-layer technique, showed photoluminescence with a high intensity containing both red and green lights. 相似文献
205.
In this study, a block copolymer of methyl methacrylate (MMA) and styrene (St) synthesized by combined ultrasonic irradiation and reverse atom transfer radical polymerization (RATRP) processes was used. PMMA-b-PSt was partially hydrolyzed and converted to a lithium salt, PMMA-b-PSt-Li, before the electrorheological (ER) measurements carried out. Average particle diameter of PMMA-b-PSt-Li polymeric salt was determined by dynamic light scattering (DLS) as 22 mum. Suspensions of PMMA-b-PSt-Li polymeric salts were prepared in silicone oil. ER properties of PMMA-b-PSt-Li/silicone oil suspensions were studied as a function of electric field strength, dispersed phase concentration, shear rate, shear stress, temperature, frequency, and polar promoter. Further dielectric properties of PMMA-b-PSt-Li ionomer were also investigated. 相似文献
206.
In the present study we consider generalized rotation surfaces imbedded in an Euclidean space of four dimensions. We also give some special examples of these surfaces in ${\mathbb E^4}$ . Further, the curvature properties of these surfaces are investigated. We give necessary and sufficient conditions for generalized rotation surfaces to become pseudo-umbilical. We also show that every general rotation surface is Chen surface in ${\mathbb E^4}$ . Finally we give some examples of generalized rotation surfaces in ${\mathbb E^4}$ . 相似文献
207.
Mehmet Erta? Bayram DevirenMustafa Keskin 《Journal of magnetism and magnetic materials》2012,324(5):704-710
The dynamic phase transitions are studied in the kinetic spin-2 Blume-Capel model under a time-dependent oscillating magnetic field using the effective-field theory with correlations. The effective-field dynamic equation for the average magnetization is derived by employing the Glauber transition rates and the phases in the system are obtained by solving this dynamic equation. The nature (first- or second-order) of the dynamic phase transition is characterized by investigating the thermal behavior of the dynamic magnetization and the dynamic phase transition temperatures are obtained. The dynamic phase diagrams are constructed in the reduced temperature and magnetic field amplitude plane and are of seven fundamental types. Phase diagrams contain the paramagnetic (P), ferromagnetic-2 (F2) and three coexistence or mixed phase regions, namely the F2+P, F1+P and F2+F1+P, which strongly depend on the crystal-field interaction (D) parameter. The system also exhibits the dynamic tricritical behavior. 相似文献
208.
The stationary states of the kinetic mixed spin-2 and spin-5/2 Ising ferrimagnetic system with repulsive biquadratic coupling
are examined within a mean-field approach under the presence of a time varying (sinusoidal) magnetic field. We employ Glauber-type
stochastic dynamics to construct a set of coupled mean-field dynamic equations, and we solve these equations to find the phases
in the system. We also investigate the thermal behavior of the dynamic order parameters to characterize the nature (continuous
or discontinuous) of the dynamic phase transitions (DPTs) and obtain the DPT points. The phase diagrams are presented in the
reduced magnetic field amplitude and reduced temperature plane, and a comparison is made with the results of other kinetic
mixed spin systems. We also study the behavior of the dynamic magnetic hysteresis and investigate the effects of the frequency
on hysteresis properties, and we find the results are in good agreement with some previous theoretical and experimental works. 相似文献
209.
Kilic Bayram Simsek Esra Bilgin Turkdogan Sunay Demircivi Pelin Tuna Özlem Mucur Selin Pravadili Berek Dusan 《Journal of nanoparticle research》2020,22(2):1-13
Journal of Nanoparticle Research - A comprehensive study of the antibacterial (bacteriostatic and bactericidal) properties of non-doped carbon nanodots (CNDs), nitrogen-doped (N-doped), and... 相似文献