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51.
L. T. Denisova L. G. Chumilina V. M. Denisov S. D. Kirik N. V. Belousova 《Physics of the Solid State》2014,56(3):645-647
Experimental data on the molar heat capacity of Lu2Cu2O5 in the temperature range 366–992 K have been obtained. The experimental data have been used to calculate the thermodynamic properties of the oxide compound. 相似文献
52.
Deniz Sinirlioglu Ali Ekrem Muftuoglu Kurtulus Golcuk Ayhan Bozkurt 《Journal of polymer science. Part A, Polymer chemistry》2014,52(13):1885-1897
This work uses a simple “grafting through” approach in the preparation of anhydrous poly(vinylidene fluoride) (PVDF)‐g‐PVTri polymer electrolyte membranes (PEMs). Alkaline‐treated PVDF was used as a macromolecule in conjunction with vinyltriazole in the graft copolymerization. The obtained polymer was subsequently doped with triflic acid (TA) at different stoichiometric ratios with respect to triazole units and the anhydrous PEMs (PVDF‐g‐PVTri‐(TA)x) were prepared. All samples were characterized by FTIR and 1H NMR. The composition of PVDF‐g‐PVTri was determined by energy dispersive spectroscopy. Thermal properties of the membranes were examined by thermogravimetric analysis and differential scanning calorimetry. The surface roughness and morphology of the membranes were studied using atomic force microscopy, X‐ray diffraction, and scanning electron microscopy. PVDF‐g‐PVTri‐(TA)3 (C3‐TA3) with a degree of grafting of 47.22% showed a maximum proton conductivity of 0.09 S cm?1 at 150 °C and anhydrous conditions. © 2014 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2014 , 52, 1885–1897 相似文献
53.
Gözde Murat Saltan Deniz Aykut Kıymaz Ceylan Zafer Haluk Dinçalp 《Journal of fluorescence》2017,27(6):1975-1984
The riboflavin dye 2,3,4,5-tetra-O-acetyl-1-[3-(6-bromohexyl)-7,8-dimethyl-2,4-dioxo-3,4-dihydrobenzo[g]pteridin-10(2H)-yl]-1-deoxypentitol and its pyridinium salt were synthesized, and studied by absorption and fluorescence spectroscopy in solutions and on thin film states. The first absorption band of riboflavin-pyridinium salt derivative is red-shifted by 10 nm compared to neutral one on film. Cationic riboflavin derivative shows significant wavelength changes on its fluorescence emission spectrum in the excited state depending on the solvent polarity and the electronic environment. The fluorescence quantum yields of cationic riboflavin gave much higher values as compared to that of its neutral form. The fluorescence lifetimes were found to be in the range of 5.5–6.6 ns with mono ? exponential behavior. These dyes possess low-lying HOMO energy levels which are suitable to be able to inject holes to donor polymers so that they can be used as acceptor component in the active layer of bulk heterojunction solar cells (BHJ-SCs). Photovoltaic responses are reported for P3HT:riboflavin active layer wherein the synthesized dyes are used as acceptor component. Also, neutral riboflavin shows greater electron mobility value of 1.3 × 10?3 cm2/V?s compared to its cationic derivative. 相似文献
54.
In this study, the possible effect of the neutron-proton pairing interaction in the heavy nuclei has been investigated in
the framework of the BCS model by making a simple approximation. This effect has been searched realistically by calculating
the moments of inertia of deformed even-even nuclei. Calculations show that the moments of inertia of rare earth nuclei changed
dramatically and approached the experimental values. 相似文献
55.
Deniz DEMR ATLI 《Turkish Journal of Chemistry》2021,45(3):577
Three new dibenzimidazolium salts bridged by 2-methylenepropane-1,3-diyl group were synthesized. Their dinuclear N-heterocyclic carbene Ag(I) complexes were prepared by the reactions of these salts with Ag2O. The structures of the synthesized compounds were defined by nuclear magnetic resonance (NMR), Fourier-transform infrared spectroscopy (FT-IR), elemental analysis, and LC-MSMS (for complexes) techniques. Stability of the silver complexes was confirmed by 1H NMR spectroscopy. Catalytic activities of Ag(I) compounds were tested for three-component coupling reaction of some aldehydes, amines, and phenylacetylene. 相似文献
56.
We numerically investigate the thermal entanglements of spins (1/2, 1) and spins (1/2, 1/2) in the three-mixed (1/2, 1, 1/2) anisotropic Heisenberg XXZ spin system on a simple triangular cell under an inhomogeneous magnetic field. We show that the external magnetic field induces strong plateau formation in the pairwise thermal entanglement for fixed parame-ters of the Hamiltonian in the cases of ferromagnetic and antiferromagnetic interactions. We also .observe an unexpected critical point at finite temperature in the thermal entanglement of spins (1/2, 1) for the antiferromagnetic case, while the entanglement of spins (1/2, 1) in the ferromagnetic case and the entanglement of spins (1/2, 1/2) in both ferromagnetic and antiferromagnetic cases almost decay exponentially to zero with increasing temperature. The critical point in the en-tanglement of spins (1/2, 1) in the antiferromagnetic case may be a signature of the quantum phase transition at finite temperature. 相似文献
57.
Atilla Evcin Nalan iek Bezir Refik Kayal Mehmet Ar Deniz Belks Kepeki 《Crystal Research and Technology》2014,49(5):303-308
Nine sets of (3 × 3) InP nanofiber samples have been successfully prepared at three different voltages (20, 25, 30 kV) and at three separate heights (5, 7, 10 cm) by electrospinning with a constant precursor flow rate of 0.3 mLh−1. The crystalline structure, thermal, morphologies and nanostructure, electrical, and optical properties of the samples are characterized by X‐ray powder diffractometer (XRD) and thermal gravity‐differential scanning calorimeter (TG‐DSC), scanning electron microscopy (SEM), by Four‐Point Probe Technique (FPPT,) and ultraviolet/visible spectrometry (UV/VIS), respectively. From these measurements, we have found the formation of stoichiometric nanostructured InP with zinc‐blende structure and having lattice parameter of a = 5.874 Å, weight loss of 64.59% and crystallization temperature of 500°C, average fiber diameter of 65.82 nm, the activation energies, Ea, of the samples, and band gap energy, Eg, of the nanofibers developed at constant applied voltage 30 kV. The band gap energies determined at different distances 5, 7, and 10 cm are found to be as 1.29, 1.37, and 1.30 eV, respectively. 相似文献
58.
Ramírez LM Smith AS Unal DB Colby RH Velegol D 《Langmuir : the ACS journal of surfaces and colloids》2012,28(9):4086-4094
Bottom-up fabrication methods are used to assemble strong yet flexible colloidal doublets. Part of a spherical particle is flattened, increasing the effective interaction area with another particle having a flat region. In the presence of a moderate ionic strength, the flat region on one particle will preferentially "bond" to a flat region on another particle in a deep (≥10 kT) secondary energy minimum. No external field is applied during the assembly process. Under the right conditions, the flat-flat bonding strength is ≥10× that of a sphere-sphere interaction. Not only can flat-flat bonds be quite strong, but they are expected to remain freely rotatable and flexible, with negligible energy barriers for rotation because particles reside in a deep secondary energy minimum with a ~20-30 nm layer of fluid between the ~1 μm radius particles. We present a controlled technique to flatten the particles at room temperature, the modeling of the interparticle forces for flattened spheres, and the experimental data for the self-assembly of flat-flat doublets. 相似文献
59.
Deniz Akta? Uygun Begüm Akduman Murat Uygun Sinan Akg?l Adil Denizli 《Applied biochemistry and biotechnology》2012,167(3):552-563
Supermacroporous poly(2-hydroxyethyl methacrylate) [poly(HEMA)] monolithic cryogel was prepared by radical cryocopolymerization of HEMA with N,N??-methylene bisacrylamide as crosslinker. Reactive Green 5 dye was immobilized to the cryogel with nucleophilic substitution reaction, and this dye attached cryogel column was used for affinity purification of papain from Carica papaya latex. Reactive Green 5-immobilized poly(HEMA) cryogel was characterized by swelling studies, Fourier transform infrared spectroscopy, scanning electron microscopy, and energy dispersive X-ray analysis. Maximum papain adsorption capacity was found to be 68.5?mg/g polymer while nonspecific papain adsorption onto plain cryogel was negligible (3.07?mg/g polymer). Papain from C. papaya was purified 42-fold in single step with dye attached cryogel, and purity of papain was shown by silver-stained sodium dodecyl sulfate?Cpolyacrylamide gel electrophoresis. 相似文献
60.
Sergei D. Kirik Ekaterina G. Yakovleva Aleksandr F. Shimanskii Yurii G. Kovalev 《Acta Crystallographica. Section C, Structural Chemistry》2001,57(12):1367-1368
The title compound, cadmium bismuth dioxide chloride, CdBiO2Cl, was obtained as a white powder by reaction of solid BiOCl with CdO at 973 K. Ab initio crystal structure determination was carried out using X-ray powder diffraction techniques, including direct methods for atom location and Rietveld fitting for the final refinement. Being monoclinic, the crystal structure can be related to tetragonal Sillen layered phases. The main structural elements present are CdBiO2+ pleated metal–oxygen layers alternating with Cl layers along the c axis, whereas along the b axis, all atoms are on mirror planes. The formation of a strong Cd—Cl bond draws the layers together, causing layer deformation and a monoclinic distortion in the layer arrangement. 相似文献