In this research an improvement of the efficiency  of vacuum microwave  tube  type      Gl-19B     had  been  done  by activation    of internal surfaces   using two specific  procedures  which can qualify  the tubes to be reused again.

The first method  was the reevacuuated  and heating treatment.

The second  method wa:s the glow discharge  method which  used ro

clean the electrodes and improve the vacuum to about!o·8 mbar.

In order   to study  the  using of  both processes   together,  Copper

samples  heate

The problem of research was the lack of research that dealt with issue of the job design approach that is more suitable for knowledge work, therefore, the research aims to determine the impact of job enrichment,  and knowledge capitalon strategic success, starting from the hypothesis that there significant impact of job enrichment and knowledge capital on strategic success, to achieve this goal the researchers from the theoretical literature and  related studies conclude to the construction of the scheme shows the hypothetical relationship between the variables, which was adopted job enrichment as independent variable while knowledge capital plays two roles, the first as an independent variable and the second as an intermediate

The performance and lifetime of the flexible asphalt pavement are mainly dependent on the interfacial bond strength between layer courses. To enhance the bond between layers, adhesive materials, such as tack coats, are used. The tack coat itself is a bituminous material, which is applied on an existing relatively non-absorbent surface to ensure a strong bond between the old and newly paved layer. The primary objective of this study was to evaluate the effects of various types of tack coat materials on interlayer bond strength and to determine the optimal application rate for each type. The tack coat types used in this paper were RC-70, RC-250, and CSS-1h. Both laboratory-prepared and field-constructed hot mix asphalt concrete pavements usin

Background: The healing period for bone–implant contact takes 3–6 months or even longer. Application of Escherichia coli-derived recombinant human bone morphogenetic protein-2 (ErhBMP-2) to implant surfaces has been of great interest on osseointegration due to its osteoinductive potential. The objective of this study was to evaluate the effect of ErhBMP-2 on implant stability. Materials and methods: A total of 48 dental implants were inserted in 15 patients. Twenty four implants coated with 0.5 mg/ml ErhBMP-2 (study group). The other 24 implants were uncoated (control group). Each patient was received at least two dental implants at the same session. Both groups were followed with repeated implant stability measurements by me

يشهد العالم تقدما في كافة مجالات الحياة المختلفة وتزداد الحياة صعوبة يوما بعد يوم, ويزداد البحث في كافة المجالات التي تعمل على خدمة الإنسان ولقد طال هذا التقدم النشاط الرياضي ,فقد يكون لتطور التدريب الرياضي وتنوع أساليبه الدور الكبير في تحقيق اللياقة البدنية التي تعد إحدى أهم الأهداف التي يرمي إليها الدرس في كلية التربية الرياضية . واللياقة البدنية تستمد أهميتها من كونها إحدى مكونات اللياقة الشاملة التي بدو

The pure and Sb doped GeSe thin films have been prepared by thermal flash evaporation technique. Both the structural and optical measurement were carried out for as deposited and annealed films at different annealing temperatures.XRD spectra revealed that the all films have one significant broad amorphous peak except for pure GeSe thin film which annealed at 573 K, it has sharp peak belong to orthorhombic structure nearly at 2θ=33o. The results of the optical studies showed that the optical transition is direct and indirect allowed. The energy gap in general increased with increasing annealing temperature and decreased with increase the ratio of Sb dopant. The optical parameters such as refractive index, extinction coefficient and real and

The pure and Sb doped GeSe thin films have been prepared by thermal flash evaporation technique. Both the structural and optical measurement were carried out for as deposited and annealed films at different annealing temperatures.XRD spectra revealed that the all films have one significant broad amorphous peak except for pure GeSe thin film which annealed at 573 K, it has sharp peak belong to orthorhombic structure nearly at 2θ=33o . The results of the optical studies showed that the optical transition is direct and indirect allowed. The energy gap in general increased with increasing annealing temperature and decreased with increase the ratio of Sb dopant. The optical parameters such as refractive index, extinction coefficient and r

The aim of the present research is concerned with study the effect of UV radiation on the optical properties at wavelengths 254, 365 nm of pure PC and anthracene doping PC films prepared using the cast method for different doping ratio 10-60 mL. Films of pure PC and anthracene doping PC were aged under UV radiation for periods of up to 360 h. It found that the effect of UV radiation at wavelength 254 nm on the optical properties is great than the effect of UV radiation at wavelength 365 nm. Also, it found that the optical energy gap of pure PC and anthracene doping PC films is stable against radiation.