In this research PbS thin film have been prepared by chemical bath deposition technique (CBD).The PbS film with thickness of (1-1.5)μm was thermally treated at temperature of 100°C for 4 hours. Some Structural characteristics was studied by using X-ray diffraction (XRD)and optical microscope photograph some of chemical gas sensing measurements were carried out ,it shown that the sensitivity of (CO2) gas depend on the grain Size and deposition substrate. The grain size of PbS film deposited on on glass closed to 21.4 nm while 37.97nm for Si substrate. The result of current-voltage characterization shwon the sensitivity of prepared film deposited on Si better than film on glass.
Objective:Fluorid-containing dental alginate impression materials can exert a considerable reduction in
enamel solubility. The objective was to evaluate the effect of fluoride addition on the setting time and
compressive strength of alginate impression materials.
Methodology: 60 samples were constructed from alginate impression material (30 samples for setting
time test and 30 samples for compressive strength test).Specimens of each test divided into three
subgroup. Group A: 10 specimens of alginate were mixed with distilled water [control], Group B: 10
specimens of alginate were mixed with100-ppm fluoride and Group C:10 specimens of alginate were
mixed with 2%Naf.
Results: the result of setting time test showed t
The applications of Ruscheweyh derivative are studied and discussed of class of meromorphic multivalent application. We get some interesting geometric properties, such as coefficient bound, Convex linear combination, growth and distortion bounds, radii of starlikenss , convexity and neighborhood property.
Introduction: This study was performed to compare the effect of Fractional CO2 laser or Q switched Nd:YAG laser of surface treatment on the shear bond strength of zirconia-porcelain interface. Methods: Fractional CO2 laser at 30 W, 2 ms, time interval 1 ms, distance between spots 0.3 mm, and number of scans is (4) or Q switched Nd:YAG laser at 30 J/mm2 and 10 Hz were used to assess the shear bond strength of zirconia to porcelain. Pre-sintered zirconia specimens were divided into three groups (n = 10) according to the surface treatment technique used: (a) untreated (Control) group; (b) CO2 group; (c) Nd:YAG group. All samples were then sintered and veneered with porcelain according to the manufacturer’s instructions. Surface morph
... Show MoreGas coning is one of the most serious problems in oil wells. Gas will reach the perforations and be produced with oil. Anyhow there is a certain production rate called critical production rate. The daily production rate should not exceed the critical production rate. In this research ten oil wells have been tested for problem of gas coning for a period of time of eighteen months. The production rates of these Ten oil wells are tabulated in a table exist in this research.
These production rates are considered as critical production rate because no gas coning has been observed in these wells. The critical production rates of these wells don't concide with those obtained from (Meyer, Gardiner, Pirson) method and also they don’t concide
In the field of research in the investment of gas fields, this requires that we first look at the center of the contracting parties in terms of the guarantee means granted to them under the contract, which constitute a means of safety and motivation to enter as major parties in the investment project. In turn, we will discuss the minimum guarantees, which are the most important guarantees granted to each of the two parties to the contract, namely the national party and the investor.
Climate change is a severe problem due to the continuous dynamic changes in urbanization in cities, and reaching it requires high-resolution spatial data represented by using remote sensing technology, as the data of the Space Science Network of NASA was relied on to measure the change in the climate of Baghdad city for a period of four decades 1981-2021, using the climate change equation referred to in the research and then tabulating the data in Excel. The results showed evident changes in the climatic rates, especially during the fourth time cycle; the high rates of temperature and low rates of relative humidity and precipitation indicate that the city’s climate is heading towards drought, and similarities appeared between the rates
... Show MoreThe change in the optical band gap and optical activation energy have been investigated for pure Poly (vinyl alcohol)and Poly (vinyl alcohol) doped with Aluminum sulphate to proper films from their optical absorption spectra. The absorption spectra were measured in the wave range from (200-700) nm at temperature range (25-140) 0C. The optical band gap (Eg) for allowed direct transition decrease with increase the concentration of Aluminum sulphate. The optical activation energy for allowed direct transition band gap was evaluated using Urbach- edges method. It was found that ?E increases with increasing the concentration of Al2 (SO4)3 and decreases when temperature increases.