There are no single materials which can withstand all the extreme operating conditions in modern technology. Protection of the metals from hostile environments has therefore become a technical and economic necessity.
In this work, for enhancing their wear-resistance, boride layers were deposited on the surface of low carbon steel by a pack cementation method at 850 °C for (2, 4, and 6) h using vacuum furnace. The boronizing process was achieved using different concentration of boron source (20, 25, and 30) % wt. into coating mixture to optimize the best conditions which ensure the higher properties with lower time. The coating was characteristic by X ray diffraction (XRD), and it is confirmed t
... Show MoreIn the current work various types of epoxy composites were added to concrete to enhance its effectiveness as a gamma- ray shield. Four epoxy samples of (E/clay/B4C) S1, (E/Mag/B4C) S2, (EPIL) S3 and (Ep) S4 were used in a comparative study of gamma radiation attenuation properties of these shields that calculating using Mont Carlo code (MCNP-5). Adopting Win X-com software and Artificial Neural Network (ANN), µ/ρ revealed great compliance with MCNP-5. By applying (µ/ρ) output for gamma at different energies, HVL, TVL and MFP have been also estimated. ANN technique was simulated to estimate (µ/ρ) and dose rates. According to the results, µ/ρ of all epoxy samples scored higher than standard concrete. Both S2 and S3 samples having h
... Show MoreThe rapid developmemt of information technology and its use in all fields has a bositive influence on all fields , and financial markets have a share of this development through the use of an electronic trading system to settle transactions and enhance transparency and disclosure in all activities of these markets and stimulate their performance .
It is worth nothing that these revolutions remove the necessity for nonstop connection with persons through the internet or phone networks , novel knowledge decreases the charges of structure original transaction system and reducing the fences of new participants entry .
The development in transportations expertise allows for quicker or
... Show MorePathological blood clot in blood vessels, which often leads to cardiovascular diseases, are one of the most common causes of death in humans. Therefore, enzymatic therapy to degrade blood clots is vital. To achieve this goal, bromelain was immobilized and used for the biodegradation of blood clots. Bromelain was extracted from the pineapple fruit pulp (Ananas comosus) and purified by ion exchange chromatography after precipitation with ammonium sulphate (0-80 %), resulting in a yield of 70%, purification fold of 1.42, and a specific activity of 1175 U/mg. Bromelain was covalently immobilized on functionalized multi-walled carbon nanotubes (MWCNT), with an enzyme loading of 71.35%. The results of the characterization of free and immobilized
... Show MoreThis new azo dye 7-(3-hydroxy-phenylazo)-quinoline-8-ol was subsequently used to prepare a series of complexes with the chlorides of Fe, Co, Zn, Ru, Rh and Cd. The compounds identified by 1H and 13C-NMR, FT-IR, UV-Vis, mass spectroscopy, as well as TGA, DSC, and C.H.N., conductivity, magnetic susceptibility, metal and chlorine content. The results showed that the ligand behaves in a trigonal behavior, and that the complexes gave tetrahedral, except for Fe, Ru and Rh octahedral was given, that all of them are non-electrolytes. The effectiveness of both the compounds in inhibiting free radicals was evaluated by the ability to act as an antioxidant was measured using DPPH as a free radical and gallic acid as a standard substance, the
... Show MoreAbstract:Porous Silicon (PSi) has been produced in this work by using Photochemical (PC) etching process by using a hydrofluoric acid (HF) solution. The irradiation has been achieved using quartz- tungsten halogen lamp. The influence of various irradiation times on the properties of PSi اmaterial such as layer thickness, etching rate and porosity was investigated in this work too. The XRD has been studied to determine the crystal structure and the crystalline size of PSi material
Porous Silicon (PSi) has been produced in this work by using Photochemical (PC) etching process by using a hydrofluoric acid (HF) solution. The irradiation has been achieved using quartz- tungsten halogen lamp. The influence of various irradiation times on the properties of PSi اmaterial such as layer thickness, etching rate and porosity was investigated in this work too.
The XRD has been studied to determine the crystal structure and the crystalline size of PSi material
In this research, we sought to identify the nature of the relationship between the exchange rate of the Chinese yuan and the value of Chinese exports, through the formulation of a standard model based on the model of common integration, and based on the data of the study and using the test "Angel-Granger" It reflects the relationship between the two research variables, through which the relationship between the RMB exchange rate and the value of Chinese exports was estimated during the period 1978-2017.
Nanocrystalline ZnO/Zeolite type A composite was prepared by simple method of operation by . the precipitation of zinc oxide and loading on zeolite 5A in one step. Characterization was made by X-ray diffraction (XRD), X-ray fluorescence(XRF), N2 adsorption- desorption for BET surface area, and Atomic force microscopy (AFM). Results showed that zinc oxide was loaded on zeolite as noticed by the characteristic peaks and was of nano scale having an average diameter of 88.57nm. The percentage loading of ZnO on zeolite A was 28.37% and the surface area was 222m2/g. The activity of the prepared catalyst was examined in the desulfurization of double hydrogenated diesel fuel. The process was investigated in a
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