The aim of this paper is to investigate the effects of Nd:YAG laser shock processing (LSP) on micro-hardness and surface roughness of 86400Cu-Zn alloy. X-ray fluorescence technique was used to analyze the chemical composition of this alloy. LSP treatment was performed with a Q-switched Nd: YAG laser with a wavelength of 1064 nm. The results show that laser shock processing can significantly increase. The micro-hardness and surface roughness of the LSP-treated sample. Vickers diamond indenter was used to measure the micro-hardness of all samples with different laser pulse energy and the different number of laser pulses. It is found that the metal hardness can be significantly increased to more than 80% by increasing the laser energy and the number of laser pulse irradiated per unit area. The relationship between laser pulse energy and the value of surface roughness is a proportionality due to the increase in ablation processes which are associated with LSP at sample surface caused by the increasing of laser pulse energy.
A polycrystalline CdTefilms have been prepared by thermal evaporation technique on glass substrate at room temperature. The films thickness was about700±50 nm. Some of these films were annealed at 573 K for different duration times (60, 120 and 180 minutes), and other CdTe films followed by a layer of CdCl2 which has been deposited on them, and then the prepared CdTe films with CdCl2 layer have been annealed for the same conditions. The structures of CdTe films without and with CdCl2 layer have been investigated by X-ray diffraction. The as prepared and annealed films without and with CdCl2 layer were polycrystalline structure with preferred orientation at (111) plane. The better structural pr
... Show MoreIn the present work, the focusing was on the study of the x-ray diffraction, dielectric constant, loses dielectric coefficient, tangent angle, alter- natively conductivity and morphology of PET/BaTio3. The PET/BaTio3 composite was prepared for polyethylene terephthalate PET polymer composite containing 0, 10, 20, 30, 40, 50, and 60 wt. % from Barium titanate BaTi03 powder. The composite of two materials leads to form mixing solution and hot-pressing method. The effect of BaTio3 on the structure and dielectric properties with morphology was studied on PET matrix polymer using XRD, LCR meter and SEM.
In the present work, the ternary compound MgxZn7-x O7Wurtzoid with variable Zn and Mg contents was analyzed using density functional theory with B3LYP 6-311G**basis set. The electronic and vibrational properties of MgxZn7-xO7 wurtzoids, were investigated, including energy gaps, bond lengths, spectral properties, such like infrared spectra and Raman. IR and Raman spectra were compared with experimental longitudinal optical modes frequency results. The theoretical results agree well with experiments and previous data. It has been found that the energy gap is increasing with the increased Mg concentration, and that the longitudinal optical position exposes a UV shift movement with an increase in the concentration.
Synthesis of a new class of Schiff-base ligand with a tetrazole moiety to form polymeric metal complexes with CoII, NiII, ZnII, and CdII ions has been demonstrated. The ligand was synthesised by a multi-steps by treating 5-amino-2-chlorobenzonitrile and cyclohexane -1,3-dione, the 5,5'-(((1E,3E)-cyclohexane-1,3-diylidene)bis(azanylylidene))bis(2-chlorobenzonitrile) was obtained. The precursor (M) was prepared from the reaction 5,5'-(((1E,3E)-cyclohexane-1,3-diylidene)bis(azanylylidene))bis(2-chlorobenzonitrile) with NaN3 to obtained (1E,3E)-N1,N3-bis(4-chloro-3-(1H-tetrazol-5-yl)phenyl)cyclohexane-1,3-diimine (N). By reacting the precursor (M) with CS2
... Show MoreThe annealing temperature (200–500 °C) effects of optical frequency response on the dielectric functions of sol–gel derived CuCoO
ABSRTACT Background: Soft liner material is become important in dental prosthetic treatment. They are applied to the surface of the dentures to achieve more equal force distribution , reduce localized pressure and improve denture retention by engaging undercut . So the aim of the study is to evaluate the effect of different surface treatment by air-abrasion AL2O3 and laser treatment with CO2 laser on improving the shear bond strength of the denture liner to acrylic denture base material . Materials and methods: the 30 specimens of heat cured acrylic denture base material (high Impact acrylic )and heat cured soft liner (Vertex ,Nether Lands )were prepared for this study .They were designed and divided according to type of the s
... Show MoreBackground: Atrophic postoperative and traumatic scarring are common cosmetic problems for patients. Combining CO2 laser ablation with a fractional photothermolysis system in a treatment known as ablative fractional resurfacing fulfilling the new demands for a lesser risk of side effects and minimal or no downtime.Objective: To assess the safety and efficacy of ablation fractional CO2 laser treatments for surgical scarring .methods: Twenty one patient ( 14 women, and 7 men ) with various skin types , I to IV , aged 3 to 48 years , presents with 24 scars between June and December 2012 , four patients excluded from study because they are not continued in follow up , the remaining 17 patient completed all 3 treatments & 6 months follow
... Show MoreThere are many causes for epistaxis but it is mainly idiopathic in type. In Management of epistaxis there are different modality either medical or cautery(chemical or galvanic) recently laser is used in management of epistaxis. The type of laser used in current study was 810 nm diode laser. The aim of the study is to evaluate its efficiency in control of active and non active idiopathic epistaxis; The design of the study is interventional therapeutic trial. The study was performed from December 2011 to December 2012 in Al Yarmouk teaching hospital at otorhinolaryngology department. In current study the diode laser is used in different power with same exposure time in all application; The power density is measured and choose the best one
... Show MoreBackground: planter fasciitis is a common condition
seen in adults and sport men, it is characterized by dull
pain in the heel, especially when getting up and
standing on the foot in the morning or after sitting for a
long time.
Recently low level laser therapy is used as a method of
treatment.
Objective: to evaluate the benefit of laser therapy in
treatment of planter fasciitis.
Methods: Out of twenty five patients with planter
fasciitis exposed to laser therapy. Laser used is (diode
type) given in two cessions per week for four weeks,
time for each cession is about (12 minutes).
Results: complete recovery seen in (32%) of patients,
moderate improvement in (16%), mild improvement in
(24%), no