Ternary semiconductors AB5C8 (A = Cu/Ag, B = In and C = S, Se or Te) have been investigated. The CuIn5S8 and AgIn5S8 have been synthesize in cubic spinel structure with space group (Fd3m), whereas CuIn5Se8, AgIn5Se8, CuIn5Te8 and AgIn5Te8 have tetragonal structures with space group P-42m. The relaxed crystal geometry, electrical properties such as electronic band structure and optoelectronic properties are predicted by using full potential method in this work. For the determination of relaxed crystal geometry, the gradient approximation (PBE-GGA) is used. All the studied compounds are semiconductors based on their band structures in agreement with the experimental results, and their bulk moduli are in the range 35 to 69 GPa. Wide absorption peaks appeared in the visible to ultraviolet energy region indicating good absorption ability of these compounds. Therefore, these semiconductors are an excellent choice for optical devices, electrochemical and photovoltaic cells. These compounds have remarkable characteristics such as direct as well as indirect band gaps with very slight difference between the two, high absorption coefficient, good photo-stability, easy inter-conversion between n- and p-type semiconductors and in manufacturing of comparatively cheap homo and hetero junction structures. AB5C8 (A = Cu/Ag; B = In and C = S, Se, Te) compounds have shown high absorption and optical conductivity in the visible region. These compounds have therefore high potential to be used as solar energy harvesting. Also these systems are optical active in the ultraviolet region too therefore can be used for high frequency optoelectronics applications.
In this paper, we have provided a very thorough analysis of a new novel chelate metal ion complex of [Cu(II),Ag(I)] prepared via the interaction with the ligand{ 2-amino-8-((4-chloro-3-hydroxyphenyl) diazenyl)azo]guanine} [LAAG], which is synthesized by diazo coupling of the 5-amino-2-chlorophenol with amino acid guanine. The ligand and its complexes are identified by a variety of techniques, like [HNMR, FTIR, and Uv-vis] spectral, thermal analysis (TGA), and element analyses (CHN). The molar ratio was achieved so that the Cu(II) complex has (1:2) (M:L) with octahedral geometry; however, the Ag(I) complex has (1:1) (M:L) with tetrahedral geometry, and the ligand acts as neutral N,N-bidentate; as well as the ligand (LAAG) and its complexe
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This research aims to find a method to synthesize nanoparticles of important metals in the fields of medicine and electronics, with high purity small in size and narrow size distribution. And it characterized by simplicity, efficiency and high productivity. To achieve this aim the effects of laser irradiation on silver and copper colloids prepared by exploding wire technique in double distilled and deionized water (DDDW) have been studied. The laser irradiation was performed using laser radiation fluence about 4 J/cm2 at 532 nm wavelength. Additional irradiation of colloids resulted in the changes of particles morphology, which were monitored by absorption spectroscopy and transmission electron microscopy methods. It was found that both
... Show MoreBackground: Many workers have described the prevalence of HBV markers and anti-HCV among selected populations including health care personnel in Iraq. The purpose of this study is to describe the demographic characteristics and risk factors of hepatitis B and C in a sample of Iraqi health care workers (HCWs).
Materials and methods: A total of 1656 HCWs selected from Baghdad city was included in this study. A questionnaire form was filled for each HCW by direct interview. The data requested
included demographic characteristics and risk factors of exposure to HBV and HCV. HCWs were screened for the presence of HBsAg, anti-HBs and anti-HCV.
Results: A higher prevalence of HBsAg, anti-HBs and anti-HCV was de
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In this work, polynomials and the finite q-exponential operator are constructed. The operator is used to combine an operator proof of the generating function with its extension, Mehler's formula with its extension and Roger's formula for the polynomials . The generating function with its extension, Mehler's formula with its extension and Rogers formula for Al-Salam-Carlitz polynomials are deduced by giving special values to polynomials .
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Colloidal dispersions of mono Au, Ag , Cu and bimetallic Ag/Au and Cu/Au
core/shell nanoparticles are synthesized by pulsed laser ablation of metals targets
immersed in 5 ml distilled water (DW). Surface Plasmon resonance (SPR) and
particle sizes are characterized by UV-VIS and HRTEM, the X-ray diffraction
shows the structure of core/shell. The Surface Plasmon resonance of the produced
nanoparticles solutions for silver nanoparticles about 402 nm and copper
nanoparticles about 636 nm. While for the core-shell observed two peaks of SPR,
Ag/Au core/shell at (406-516) nm, and Cu/Au core/shell observed one peak at
565nm, because the region of gold and copper close together. The shape and
particle size have been con
Cerium oxide CeO2, or ceria, has gained increasing interest owing to its excellent catalytic applications. Under the framework of density functional theory (DFT), this contribution demonstrates the effect that introducing the element nickel (Ni) into the ceria lattice has on its electronic, structural, and optical characteristics. Electronic density of states (DOSs) analysis shows that Ni integration leads to a shrinkage of Ce 4f states and improvement of Ni 3d states in the bottom of the conduction band. Furthermore, the calculated optical absorption spectra of an Ni-doped CeO2 system shifts towards longer visible light and infrared regions. Results indicate that Ni-doping a CeO2 system would result in a decrease of the band gap. Finally,
... Show MoreCerium oxide (CeO2), or ceria, has gained increasing interest owing to its excellent catalytic applications. Under the framework of density functional theory (DFT), this contribution demonstrates the eect that introducing the element nickel (Ni) into the ceria lattice has on its electronic, structural, and optical characteristics. Electronic density of states (DOSs) analysis shows that Ni integration leads to a shrinkage of Ce 4f states and improvement of Ni 3d states in the bottom of the conduction band. Furthermore, the calculated optical absorption spectra of an Ni-doped CeO2 system shifts towards longer visible light and infrared regions. Results indicate that Ni-doping a CeO2 system would result in a decrease of the band gap. Finally,
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