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1.
Journal of Radioanalytical and Nuclear Chemistry - The aim of this study is the synthesis of a novel 99mTc-labeld graft polymer and the biological evaluation of its in vitro and in vivo properties....  相似文献   
2.
Sputtering technique has been used for the deposition of AgGaSe2 thin films onto soda-lime glass substrates using sequential layer-by-layer deposition of GaSe and Ag thin films. The analysis of energy dispersive analysis of X-ray (EDXA) indicated a Ga-rich composition for as-grown samples and there was a pronounce effect of post-annealing on chemical composition of AgGaSe2 thin film. X-ray diffraction (XRD) measurements revealed that Ag metallic phase exists in the amorphous AgGaSe2 structure up to annealing temperature 450 °C and then the structure turned to the single phase AgGaSe2 with the preferred orientation along (1 1 2) direction with the annealing temperature at 600 °C. The surface morphology of the samples was analyzed by scanning electron microscopy (SEM) measurements. The structural parameters related to chalcopyrite compounds have been calculated. Optical properties of AgGaSe2 thin films were studied by carrying out transmittance and reflectance measurements in the wavelength range of 325-1100 nm at room temperature. The absorption coefficient and the band gap values for as-grown and annealed samples were evaluated as 1.55 and 1.77 eV, respectively. The crystal-field and spin-orbit splitting levels were resolved. These levels (2.03 and 2.30 eV) were also detected from the photoresponse measurements almost at the same energy values. As a result of the temperature dependent resistivity and mobility measurements in the temperature range of 100-430 K, it was found that the decrease in mobility and the increase in carrier concentration following to the increasing annealing temperature attributed to the structural defects (tetragonal distortion, vacancies and interstitials).  相似文献   
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FT-IR and FT-Raman spectra of 5-methoxysalicylic acid (5MeOSA) have been experimentally reported in the region of 4000–10 cm−1 and 4000–50 cm−1, respectively. The optimized geometric parameters, conformational equilibria, normal mode frequencies and corresponding vibrational assignments of 5MeOSA (C8H8O4) are theoretically examined by means of B3LYP hybrid density functional theory (DFT) method together with 6-31++G(d,p) basis set. Furthermore, reliable vibrational assignments have made on the basis of potential energy distribution (PED) calculated and the thermodynamics functions, highest occupied and lowest unoccupied molecular orbitals (HOMO and LUMO) of 5MeOSA have been predicted. Calculations are employed for different conformations of 5MeOSA, both in gas phase and in solution. Solvent effects are investigated using chloroform and dimethylsulfoxide. All results indicate that B3LYP method is able to provide satisfactory results for predicting vibrational frequencies and the structural parameters, vibrational frequencies and assignments, IR and Raman intensities of 5MeOSA are solvent dependent.  相似文献   
5.
New Hofmann type benzene clathrates in the form of M(CyHEA)2Ni(CN)4·2benzene (where CyHEA=2-(1-cyclohexenyl)ethylamine and M=Ni or Cd) have been prepared in powder form and FT-IR and Raman spectra have been reported. The results suggest that title compounds are similar in structure to Hofmann type clathrates and their structures consist of polymeric layers of |M-Ni(CN)4|∞ with the CyHEA molecule bounded to the metal atoms (M).  相似文献   
6.
New Hofmann-T(d) type clathrates in the form of Ni(4-Phpy)(2)M(CN)(4)·2G (where 4-Phpy=4-phenylpyridine, M=Cd or Hg and G=1,4-dioxane) have been prepared in powder form and their FT-IR and Raman spectra have been reported. The results suggest that these compounds are similar in structure to the Hofmann-T(d) type clathrates.  相似文献   
7.
This research was focused on the preparation of mixed metal oxide pigments doped with terbium ions with the general formula of Sn0.752Co0.08P0.16Tb0.008O2. These pigments were synthesised by solid-state reactions at high calcination temperatures. The temperature range was chosen from 1350 to 1500 °C. The goal was to develop conditions for the synthesis of this type of pigments and to determine the influence of terbium ions on the colour properties of these compounds. All prepared pigments were applied into the organic matrix and into the ceramic glaze. Thermal behaviours of the reaction mixtures were investigated using differential thermal and thermogravimetric analysis. Synthesised Sn0.752Co0.08P0.16Tb0.008O2 pigments were compared with concurrently prepared pigment Sn0.760Co0.08P0.16O2 depending on the calcination temperature with respect to the colour properties in CIE L*a*b* colour space, furthermore from the point of particle size distribution and phase composition. All compounds provided blue–violet hues that are stable in ceramic glazes.  相似文献   
8.
New Hofmann type complexes in the form of M(pp)(2)Ni(CN)(4) (where pp=1-phenylpiperazine and M=Ni, Co, Cd, Pd or Mn) have been prepared in powder form and their infrared spectra have been reported in the range of (4000-400) cm(-1). The thermal behaviours of these complexes have been investigated by differential thermal analysis (DTA) and thermo-gravimetric analysis (TGA). Ni(pp)(2)Ni(CN)(4) complex has been examined via transmission electron microscope (TEM). The results suggest that these compounds are similar in structure to Hofmann type complexes and their structures consist of polymeric layers |M-Ni(CN)(4)|(infinity) with the pp molecule bounded to the metal atom (M).  相似文献   
9.
FT-IR and (1)H, (13)C, DEPT, COSY, NOESY, HETCOR, INADEQUATE NMR spectra of 1-phenylpiperazine (pp) have been reported for the first time except for its (1)H NMR spectrum. The vibrational frequencies and (1)H, (13)C NMR chemical shifts of pp (C(10)H(14)N(2)) have been calculated by means of the Hartree-Fock (HF) and Becke-Lee-Yang-Parr (BLYP) or Becke-3-Lee-Yang-Parr (B3LYP) density functional methods with 6-31G(d) and 6-31G(d,p) basis sets, respectively. Comparison between the experimental and the theoretical results indicates that density functional B3LYP method is superior to the scaled HF and BLYP approach for predicting vibrational frequencies and NMR properties.  相似文献   
10.
N‐implantation to GaSe single crystals was carried out perpendicular to c‐axis with ion beam of 6 × 1015 ions/cm2 dose having energy values 30 keV and 60 keV. Temperature dependent electrical conductivities and Hall mobilities of implanted samples were measured along the layer in the temperature range of 100‐320 K. It was observed that N‐implantation decreases the resistivity values down to 103 Ω‐cm depending on the annealing temperature, from the room temperature resistivity values of as‐grown samples lying in the range 106‐107 Ω‐cm. The temperature dependent conductivities exhibits two regions (100‐190 and 200‐320 K) with the activation energies of 234‐267 meV and 26‐74 meV, for the annealing temperatures of 500 and 700 °C, respectively. The temperature dependence of Hall mobility for the sample annealed at 500 °C shows abrupt increase and decrease as the ambient temperature increases. The analysis of the mobility‐temperature dependence in the studied temperature range showed that impurity scattering and lattice scattering mechanisms are effective at different temperature regions with high temperature exponent. Annealing of the samples at 700 °C shifted impurity scattering mechanism toward higher temperature regions. In order to obtain the information about the defect produced by N‐implantation, the carrier density was analyzed by using single donor‐single acceptor model. We found acceptor ionization energy as Ea = 450 meV, and acceptor and donor concentration as 1.3 × 1013 and Nd = 3.5 × 1010 cm−3, respectively. (© 2003 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)  相似文献   
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