In this work, the spectra for plasma glow produced by pulse
Nd:YAG laser (λ=532 and 1064nm) on Ag:Al alloy with same molar
ratio samples in distilled water were analyzed by studying the atomic
lines compared with aluminum and silver strong standard lines. The
effect of laser energies of the range 300 to 800 mJ on spectral lines,
produced by laser ablation, were investigated using optical
spectroscopy. The electron temperature was found to be increased
from 1.698 to 1.899 eV, while the electron density decreased from
2.247×1015 to 5.08×1014 cm-3 with increasing laser energy from 300
to 800 mJ with wavelength of 1064 nm. The values of electron
temperature using second harmonic frequency are greater than of
1064 nm, which increased from 2.405 to 2.444 eV, while the electron
density decreased from 2.210×1015 to 1.516×1015 cm-3 with
increasing laser energy for the same energy range.
An experimental investigation has been carried out for zinc-nickel (Zn-Ni) electro-deposition using the constant applied current technique. Weight difference approach method was used to determine the cathode current efficiency and deposit thickness. Also, the influence effect of current density on the deposition process, solderability, and porosity of the plating layer in microelectronic applications were examined. The bath temperature effect on nickel composition and the form of the contract was studied using Scanning Electron Microscope (SEM). Moreover, elemental nature of the deposition was analyzed by Energy Dispersive X-Ray (EDX).
It has been found that the best bath temperature
... Show MoreCorrosion behavior of aluminum alloy 7025 was investigated in hydrochloric acid (pH=1) containing 0.6 mol.dm-3 NaCl in the existence and absence of diverse concentrations of sulphamethoxazole as environmentally friendly corrosion inhibitor over the temperature range (298-313)K. Electrochemical polarization method using potentiostatic technique was employed. The inhibition efficiency has been raised with increased sulphamethoxazole concentration but lessened at temperature increases. The highest efficiency value was 96.5 at 298 K and 2 x10-4 mol.dm-3 concentration of sulphamethoxazole. The sulphamethoxazole adsorption was agreed with Langmuir adsorption isotherm. Some thermodynamic parameter (△Gads) and activation energy (Ea) were determin
... Show MoreThe present study was conducted to evaluate the effect of different inhibitors on the corrosion rate of aluminum in 50% (v/v) ethylene glycol solution at 80°C and pH 8.0 in which the electrochemical technique of linear sweep voltammetry was employed to characterize each inhibitor function and to calculate the corrosion rate from Tafel plots generated by a computer assisted potentiostat.
It is found that both sodium dichromate and borax reduces the corrosion rate by polarizing the anodic polarization curve while sodium phosphate, potassium phosphate, and sodium benzoate reduces the corrosion rate by polarizing both the anodic and cathodic polarization curve.
When inhibitor concentration increases from I g/l up
... Show MoreIn this work the corrosion behavior of Ti-6Al-4V alloy was studied by using galvanostatic measurements at room temperature in different media which includ sodium chloride (food salt), sodium tartrate (presence in jellies, margarine, and sausage casings,etc.), sodium oxalate (presence in fruits, vegetables,etc.), acetic acid (presence in vinegar), phosphoric acid (presence in drink), sodium carbonate (presence in 7up drink,etc.), and sodium hydroxide in order to compare.
Corrosion parameters were interpreted in th
... Show MoreThe microstructure and wear properties of 392 Al alloy with different Mg contents were studied using centrifugal casting. All melted alloys were heated to 800 ºC and poured into the preheated centrifugal casting mold (200-250 ºC) at different mould rotational speeds (1500, 1900 and 2300 r.p.m). It is clear from the results obtained that wear rate was dependent on the Mg content, applied load and mould rotational speed. Furthermore, wear test showed that the minimum wear rate was found in the inner layer of produced rings at mould rotational speed of 1900 r.p.m and Mg content of 5%.
This paper focuses on the optimization of drilling parameters by utilizing “Taguchi method” to obtain the minimum surface roughness. Nine drilling experiments were performed on Al 5050 alloy using high speed steel twist drills. Three drilling parameters (feed rates, cutting speeds, and cutting tools) were used as control factors, and L9 (33) “orthogonal array” was specified for the experimental trials. Signal to Noise (S/N) Ratio and “Analysis of Variance” (ANOVA) were utilized to set the optimum control factors which minimized the surface roughness. The results were tested with the aid of statistical software package MINITAB-17. After the experimental trails, the tool diameter was found as the most important facto
... Show MoreDC planar sputtering system is characterized by varying discharge potential of (250-2000 volt) and Argon gas pressures of (3.5×10-2 – 1.5) mbar. The breakdown voltage for silver electrode was studied with a uniform electric field at different discharge distances, as well as plasma parameters. The breakdown voltage is a product of the Argon gas pressure inside the chamber and gab distance between the electrodes, represent as Paschen curve. The Current-voltage characteristics curves indicate that the electrical discharge plasma is working in the abnormal glow region. Plasma parameters were found from the current-voltage characteristics of a single probe positioned at the inter-cathode space. Typical values of the electron temperature an
... Show MoreThis research was conducted to measure the safety of heat stable enterotoxin a (STa) produced by enterotoxigenic Escherichia coli, through studying its toxic effect on human blood lymphocyte, since it showed a promising effect in reducing the proliferation of colorectal cancer cells. the cytogenetic effects of (STa) by using five different concentrations (100, 200, 400, 800 and 1600μg/ml) in comparison with negative (PBS, Phosphate buffer saline) and positive (MMC, Mitomycin C) at concentration of 5μg/ml, controls on human blood lymphocytes obtained from both (10) normal healthy persons and (20) colorectal cancer patients was measured by employing the following parameters: mitotic index, blast index, chromosomal aberrations and micronucle
... Show MoreNon-thermal argon plasma needle at atmospheric pressure was
constructed. The experimental setup was based on a simple and low
cost electric component that generates a sufficiently high electric
field at the electrodes to ionize the argon gas which flow at
atmospheric pressure. A high AC power supply was used with 1.1
kV and 19.57 kHz. Non-thermal Argon plasma used on blood
samples to show the ability of non-thermal plasma to promote blood
coagulation. Three tests have been done to show the ability of plasma
to coagulate both normal and anti-coagulant blood. Each blood
sample has been treated for varying time from 20sec. to 180sec. at
different distances. The results of the current study showed that the
co