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The violated commutation condition between the total shell model Hamiltonian and Gamow-Teller operator (GT) has been restored
by Pyatov method (PM). The considered nuclear model Hamiltonian in PM includes the separable GT residual interaction in ph
and pp channels and is differentiated from the traditional schematic model by h
0(restoration term). The influence of the h
0 effective interaction on the 2νββ decay of 48Ca, 76Ge, 82Se, 96Zr, 100Mo, 116Cd, 128,130Te and 136Xe is investigated. All the calculations have been done within the framework of standard QRPA. The results obtained by PM
are compared with those of other approaches and experimental data. The influence of the restoration term on the stability
of the 2νββ decay nuclear matrix elements is analysed.
相似文献
34.
Boyle Cullen Liang Liang Romo-De-La-Cruz Cesar-Octavio Johnson Robert Chen Yun Prucz Jacky Cakmak Ercan Watkins Thomas R. Lara-Curzio Edgar Song Xueyan 《Journal of Sol-Gel Science and Technology》2018,85(3):712-722
Journal of Sol-Gel Science and Technology - We report on the influence of sintering gas atmosphere on the thermoelectric (TE) performance of Ca3Co4O9?+?δ ceramics made from... 相似文献
35.
Akdemir ZS Akçakaya H Kahraman MV Ceyhan T Kayaman-Apohan N Güngör A 《Macromolecular bioscience》2008,8(9):852-862
In this study, photopolymerized hydrogels of fumarated poly(ethylene glycol) diglycidyl-co- poly(ethylene glycol) diacrylate have been synthesized and modified with cell adhesion peptide, Arg-Gly-Asp (RGD). The structural and mechanical properties of the hydrogels are found to be poly(ethylene glycol) diacrylate (PEGDA) dependent. The percentage of gelation is increased from 72 to 89 wt.-% when the amount of the crosslinker co-monomer (PEGDA) in the hydrogel formulation is increased from 20 to 40 wt.-%. In the present case, the equilibrium mass swelling is decreased from 216 to 93%. The viscosities of the uncured formulations have also been measured and likewise, the results were influenced by the increasing amount of PEGDA that reduced the value from 83 to 36 cP. The compressive modulus of the prepared hydrogels was improved with the addition of the PEGDA. Cell growth experiments have been performed by comparing the properties of the hydrogels with and without RGD units. The results show that RGD units enhance the adhesion of cells to the surface of the hydrogels. SEM-EDS studies reveal that nitrogen and calcium are produced on the osteoblast-seeded surface of the scaffold within the culture time period. [Figure: see text]. 相似文献
36.
The synthesis and photoconductivity properties of the alkylthia and triethyleneoxysulfonyl substituted oxotitanium(IV) phthalocyanines (1a and 2a) are reported for the first time. The new compounds have been characterized by elemental analysis, IR, 1H and 13C NMR spectroscopy, electronic spectroscopy and mass spectroscopy. The mesogenic properties of these new materials were studied by differential scanning calorimetry and optical microscopy. The electrical dark conductivities (σd) and photoconductivities (σph) of deposited films of 1a and 2a were investigated in various media with different concentrations of oxygen. Molecular oxygen increases photoconductivities (σph) significantly. The photoconductivity mechanism and formation of Pc+ which is positive charge carrier under the light irradiation of the phthalocyanine molecules are demonstrated using the theoretical calculations. The geometries of the oxotitanium(IV) phthalocyanines (TiOPc) are optimized with PM3 semi-empirical method, and their visible absorption maxima are calculated with ZINDO/S method. The results agree well with the observed values. It was found that for the calculation of visible absorption of neutral and positively charged substituted TiOPc molecules using ZINDO/S method could rapidly yield excellent results. Dipole moment, HOMO, LUMO energies and atomic charges are also calculated for clarification of the oxygen effect on the photoconductivity using PM3 and ZINDO/S methods. 相似文献
37.
Melek Pamuk Algi Zahide Oztas Seha Tirkeş Atilla Cihaner Fatih Algi 《Journal of fluorescence》2017,27(2):509-519
Two chemiluminescent compounds containing 2,5-di(thien-2-yl)pyrrole and pyridazine units, namely 5,7-di(thiophen-2-yl)-2,3-dihydro-1H-pyrrolo[3,4-d]pyridazine-1,4(6H)-dione (5) and 6-phenyl-5,7-di(thiophen-2-yl)-2,3-dihydro-1H-pyrrolo[3,4-d]pyridazine-1,4(6H)-dione (6), were successfully synthesized and electrochemically polymerized. The compounds have chemiluminescent properties and glow in the presence of hydrogen peroxide in basic medium. The intensity of the glow can be increased dramatically by using Fe3+ ions, hemin (1.0 ppm) or blood samples (1.0 ppm) as catalyst. The compounds 5 and 6 have one well-defined irreversible oxidation peak at 1.08 V and 1.33 V vs Ag/AgCl, respectively. Electrochemical polymerization of both 5 and 6 were carried out successfully by repeating potential scanning in the presence of BF3. Et2O in an electrolyte solution of 0.1 M LiClO4 dissolved in acetonitrile. The electronic band gaps (Eg) of the polymers P5 and P6 were found to be 2.02 eV and 2.16 eV, respectively. On the other hand, the corresponding polymers are electroactive and exhibited electrochromic features. 相似文献
38.
S. Sebnem Cetin S. Corekci M. Cakmak S. Ozcelik 《Crystal Research and Technology》2011,46(11):1207-1214
Titanium dioxide (TiO2) thin film was deposited on n‐Si (100) substrate by reactive DC magnetron sputtering system at 250 °C temperature. The deposited film was thermally treated for 3 h in the range of 400‐1000 °C by conventional thermal annealing (CTA) in air atmosphere. The effects of the annealing temperature on the structural and morphological properties of the films were investigated by X‐ray diffraction (XRD) and atomic force microscopy (AFM), respectively. XRD measurements show that the rutile phase is the dominant crystalline phase for the film annealed at 800 °C. According to AFM results, the increased grain sizes indicate that the annealing improves the crystalline quality of the TiO2 film. In addition, the formation of the interfacial SiO2 layer between TiO2 film and Si substrate was evaluated by the transmittance spectra obtained with FTIR spectrometer. The electronic band transitions of as‐deposited and annealed films were also studied by using photoluminescence (PL) spectroscopy at room temperature. The results show that the dislocation density and microstrain in the film were decreased by increasing annealing temperature for both anatase and rutile phases. (© 2011 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim) 相似文献
39.
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
40.
M. Atilla Tasdelen Baris Kiskan Yusuf Yagci 《Macromolecular rapid communications》2006,27(18):1539-1544
Summary: Free radical polymerization of methyl methacrylate (MMA) is initiated upon irradiation at λ > 350 nm in CH2Cl2 that contains benzoxazine (P‐a) and one of the following photosensitizers: benzophenone (BP), thioxanthone (TX), 2‐chlorothioxanthone (CTX), 2‐isopropyl thioxanthone (ITX), and camphorquinone (CQ). The postulated mechanism is based on the intermolecular reaction of the excited photosensitizer with the tertiary amino moiety of the ground state P‐a and a subsequent hydrogen abstraction reaction. The resulting aminoalkyl radicals initiate the polymerization. The incorporation of P‐a groups into polymers is demonstrated by spectroscopic methods. The possibility of deep curing using the described photoinitiating system followed by the thermal ring opening of the incorporated P‐a groups is also demonstrated.