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.
Background: Although radiological diagnostic studies (RDS) are an important and acceptable part of medical practice, it is not without hazards. It is associated with increased risk of cancer. Unfortunately the typical and safe dose of each radiological examination is not known. Most of our knowledge of cancer risk comes from studies of survivors of those exposed to whole body radiation from atomic bomb in Hiroshima & Nagasaki, jobs associated with radiation exposure, Chernobyl survivors & patients treated with radiation therapy for cancer and other diseases.
Objectives To estimate radiation dose received by patients from diagnostic radiological examinations and lifetime
... Show Moreالوصف In this time, most researchers toward about preparation of compounds according to green chemistry. This research describes the preparation of 2-fluoro-5-(substituted benzylideneamino) benzonitrile under reflux and microwave methods. Six azomethine compounds (B1-6) were synthesized by two methods under reflux and assisted microwave with the comparison between the two methods. Reflux method was prepared of azomethine (B1-6) by reaction of 5-amino-2-fluorobenzonitrile with some aldehyde derivatives with (50–100) mL of absolute ethanol and some quantity of GAA and time is limited between (2–5) hours with a yield between (60–70) percent with recrystallization for appropriate solvents. But the microwave-assisted method was synthe
... Show MoreThe research aims to use a new technology for industrial water concentrating that contains poisonous metals and recovery quantities from pure water. Therefore, the technology investigated is the forward osmosis process (FO). It is a new process that use membranes available commercial and this process distinguishes by its low cost compared to other process. Sodium chloride (NaCl) was used as draw solution to extract water from poisonous metals solution. The driving force in the FO process is provided by a different in osmotic pressure (concentration) across the membrane between the draw and poisonous metals solution sides. Experimental work was divided into three parts. The first part includes operating the forward osmosis process using T
... Show MoreHuman resources have been regarded as the most important asset for any organization because of its essential part in achieving the sustainable competitive advantage and survival. Managing human resources is very challenging and requires an effective bundle of practices that contribute to attaining the organizational goals. This study tries to confirm the importance of HRM practices in small businesses which came to play a vital role in the economies of the world, through clarifying the influence of HRM practices on the organizational performance, using a mediating variable (employees’ outcomes). Also the study attempts to highlight the key role of governmental support from view point of small businesses, through verifying the significant
... Show MoreA new method for the determination of the drug cefalexin in some Pharmaceuticals using (UV-Vis) and indirect Flame Atomic Absorption Spectrophotometer (FAAS) , Fe III should forms a chelating complex with cefalexin (CEX –Fe III) at pH (1-8) and the best pH for the formation of (CEX –Fe III) chelating complex was (2) .The complex extracted with Methanol and Dimethy-Sulphoxide .The mole-ratio method has been used to determine the structure of chelate (CEX - Fe III) and found to be 2:1 LM ( Ligand : Metal.) .
Keywords : Cefalexin , chelating complex.
Background: Selenium-73 with half- life of 7.15 hour emits β+ in nature and has six stable isotopes which are ( 74Se,76Se,77Se,78Se,80Se and 82Se ). Selenium-73 has many applications in technology and radioselenium compounds of metallic have found various applications in medicine.
Objective: To make a comparison between different reactions that produced cross sections of Se-73 radioisotopes.
Subjects and methods: The feasibility of the production of Selenium -73 via various nuclear reactions was investigated. Excitation functions of 73Se production by the re
... Show MoreThe present study was conducted to estimate the antimicrobial activity and the potential biological control of the killer toxin produced by
El estudio se clasifica dentro los estudios teóricos sobre literatura que se ocupa del estudio de los métodos de la crítica literaria: El Estructralismo literario francés y el Formalismo ruso del siglo XX que se utilizan en la interpretación literaría. Las dos corrientes literarias estudian la literatura como ciencia que busca aplicar un método científico al estudio de la literatura. Dicho estudio trata de exponer las teorías críticas que surgen en el debate de la interpretación de los textos literarios como el de Susan Sontag, Ricoeur Paul y Mijail Bajitin, etc. Además se incluye algunos ejemplos implican el análisis estructuralista y formalista como Kafka y la tragedia Judía. y Sur Racine.
ABSTRACT:
... Show MoreThis research was aimed to study the osmotic efficiency of the draw solutions and the factors affecting the performance of forward osmosis process : The draw solutions used were magnesium sulfate hydrate (MgSO4.7H2O) pojtassium chloride (KCL), calcium chloride (CaCl2) and ammonium bicarbonate (NH4HCO3). It was found that water flux increases with increasing draw solution concentration, and feed solution flow rate and decreases with increasing draw solution flow rate and feed solution concentration. And also found that the efficiency of the draw solutions is in the following order:
CaCl2> KCI > NH4HCO3> MgSO4.7H