This study rigorously investigates three 3d transition metal carbide (TMC) structures via LDA and GGA approximations. It examines cohesive energy (Ecoh), Vickers hardness (Hv), mechanical stability, and electronic properties. Notably, most 3d TMCs exhibit higher cohesive energy than nitrides, and rs-TiC demonstrates a Vickers hardness of 25.66 GPa, outperforming its nitride counterpart. The study employs theoretical calculations to expedite research, revealing mechanical stability in CrC and MnC (GGA) and CrC (LDA in cc structure), while all 3d TMCs in rs and seven in zb structures show stability. Charge transfer and bonding analysis reveal enhanced covalency along the series, influenced by the interplay between p orbitals of carbon and d orbitals of the metal. Most 3d TMCs exhibit metallic properties, excluding zb-TiC and zb-FeC in all phases. An inverse correlation between elastic constant C44 and electronic states near the Fermi level (EF) emerges, guiding applications and design. This study efficiently uncovers 3d TMC properties, offering insights for applications and design.
The preparation and characterization of the Cu (II), Co(II), Ni(II), Zn(II), Cd(II), and Hg(II) metal complexes of heterocyclic azo ligand 2-[(4`-sulphamide phenyl) azo] -4,5-diphenyl imidazole (4-SuBAI) have been studied by elemental analysis, FT-IR and UV-Vis Spectroscopic, magnetic moment and molar conductance methods. The analytical data showed that all chelate complexes were prepared with (metal-ligand) ratio of (1:2). The general formula of these complexes was [ML2X2]. nH2O [were L=2-[(4`-sulphamide phenyl) azo]-4,5-diphenyl imidazole and X=Cl, and the octahedral geometry were suggested for these complexes .
In the present work, different thicknesses of CdS film were prepared by chemical bath deposition. Z-Scan technique was used to study the nonlinear refractive index and nonlinear absorption coefficients. Linear optical testing were done such as transmission test, and thickness of films were done by the interference fringes (Michelson interferometer). Z-scan experiment was performed at 650nm using CW diode laser and at 532nm wavelength. The results show the effect of self-focusing and defocusing that corresponds with nonlinear refraction n2. The effect of two-photon absorption was also studied, which correspond to the nonlinear absorption coefficient B.
Synthesis, characterization and pharmaceutical studies of schiff base from 2-pyrrolidinone derivative and imidazole-2-carboxaldehyde and corresponding complexes with Metal (||)
The new azo dye was prepared from the reaction of the diazonium salt derived from 3-aminophenol with 2- hydroxyquinoline, then it was used to prepare a series of complexes with the chlorides of cobalt, chromium, copper, nickel, platinum, palladium and ammonium molybdate. The ligand was identified by a proton and carbon nuclear magnetic resonance spectroscopy, and the compounds were collected. The prepared materials were subjected to infrared, ultraviolet-visible, and mass spectrometry, as well as thermogravimetric analysis, differential calorimetry, and elemental analysis. Conductivity, magnetic susceptibility, metal content, and chlorine content of the complexes were also measured. The results showed that the ligand behaves in a trigonal b
... Show MoreDoxycycline hyclate is an antibiotic drug with a broad‐spectrum activity against a variety of gram‐positive and gram‐negative bacteria and is frequently used as a pharmacological agent and as an effector molecule in an inducible gene expression system. A sensitive, reliable and fast spectrophotometric method for the determination of doxycycline hyclate in pure and pharmaceutical formulations has been developed using flow injection analysis (FIA) and batch procedures. The proposed method is based on the reaction between the chromogenic reagent (V4+) and doxycycline hyclate in a neutral medium, resulting in the formation of a yellow compound that shows maximum absorbance at 3
Background: The most widely used material for fabrication of denture base is poly methyl methacrylate, despite its popularity, the main problems associated with it as a denture base material are poor strength particularly under fatigue failure inside the patient mouth, impact failure outside the patient mouth, which are the main causes for fracture of denture, several studies was done to increase mechanical properties of denture base. The present study was conducted to evaluate and compare the effect of addition single walled carbon nanotubes in different concentrations to polymethyl methacrylate on some mechanical properties (surface hardness, surface roughness, impact strength and transverse strength). Materials and methods: Forty eight
... Show MoreIn Iraq, the risk of soil pollution by petroleum products increases with the growth of oil exploration, production and shipping large quantities of oil through pipelines over thousands of kilometers. Numerous oil spills have been documented recently in many sites due to damage in the oil industry infrastructures, which have led to soil contamination causing serious environmental hazards and deterioration to the soil and its engineering properties. So, it is essential to investigate the impact of oil leakage through the soil stratum consequently, assessing the eligibility of the contaminated soil for construction projects or identifying the appropriate treatment method. The paper investigates the general behaviour and the associated variatio
... Show MoreABSTRACT Background: One of the methods used in the treatment of maxillofacial fracture is intermaxillary fixation(IMF), the most common type is the Erich arch bar with interdental wiring. This study was conducted to investigate the impact of intermaxillary fixation on gingival health condition among a group of patients with facial fracture in relation to salivary physical properties. Materials and methods: Thirty patients with an age range of (17-37) years old with facial fractures and indicated for IMF. Plaque index and gingival index (Loe, 1967) were used to assess both of them before application and after removal of IMF. Unstimulated saliva sample collection was carried out under standardized conditions according to Navazesh and Kum
... Show MoreChildhood is characterized by ahigh privacy in the life of the child overall educational institutions in the world. Based on this specificity, modern education begins with a holistic vision of the child through all developmental aspects (moral, religious, emotional, social, linguistic, physical, health, and mental). This integration could be achieved through taking into consideration the needs and rights of children and developing curricula that consider these needs and capacities to provide opportunities for developing and supporting the developmental aspects of the child. The contemporary technological developments in the field of computer and the Internet have brought with it new forms, ideas, and problems for children in recent years
... Show MoreThe syntheses, characterizations and structures of three novel dichloro(bis{2-[1-(4-methoxyphenyl)-1H-1,2,3-triazol-4-yl-κN3]pyridine-κN})metal(II), [M(L)2Cl2], complexes (metal = Mn, Co and Ni) are presented. In the solid state the molecules are arranged in infinite hydrogen-bonded 3D supramolecular structures, further stabilized by weak intermolecular π…π interactions. The DFT results for all the different spin states and isomers of dichloro(bis{2-[1-phenyl-1H-1,2,3-triazol-4-yl-κN3]pyridine-κN})metal(II) complexes, [M(L1)2Cl2], support experimental measurements, namely that (i) d5 [Mn(L1)2Cl2] is high spin with S = 5/2; (ii) d7 [Co(L1)2Cl2] has a spin state of S = 3/2, (iii) d8 [Ni(L1)2Cl2] has a spin state of S =
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