This work deals with the effect of adding aluminum nanoparticles on the mechanical properties, micro-hardness and porosity of memory-shape alloys (Cu-Al-Ni). These alloys have wide applications in various industrial fields such as (high damping compounds and self-lubricating applications). The samples are manufactured using the powder metallurgy method, which involved pressing in only one direction and sintered in a furnace surrounded by an inert gas. Four percentages (0%, 5%, 10%, and 15%) of aluminum nanoparticles were fabricated, which depended on the weight of aluminum powder (13%) in the sample under study. To find out which phase is responsible for the reliability of the formation of this type of alloy and its porosity, X-ray diffraction (XRD) and scanning electron microscopy (SEM) tests are used. The Vickers micro-hardness and porosity properties of these alloys were studied using a Vickers micro-hardness and porosity tester according to ASTM b328-1996. The results showed that increasing the concentration of aluminum nanoparticles in the alloy led to an increase in hardness with a decrease in the porosity, and the sample (15%) gave the best hardness (190.8 HV). The sample (0%) gave the highest porosity (19.573) %.
نحو تعزيز المشاركة السياسية للطالبات الجامعيات الفلسطينيات
The research aims to study the reliability of government institutions, including the audit directors, which are one of the most important oversight formations in the Ministry of Construction, Housing and Public Municipalities, on which the responsibility for comprehensive auditing of all the Ministry's (municipalities) formations falls on the Managing the Audit Program according to the specification (ISO 19011: 2018) to improve the audit performance which requires compliance with the application of the audit management system in accordance with the standard Specification (ISO 19011: 2018), depending on the methodology of the case study, and using of checklists, which were chosen ac
... Show MoreLiquid-Liquid Extraction of Cu(II) ion in aqueous solution by dicyclohexyl-18-crown-6 as extractant in dichloroethane was studied .The extraction efficiency was investigated by a spectrophometric method. The reagent form a coloured complex which has been a quantitatively extracted at pH 6.3. The method obeys Beer`s law over range from (2.5-22.5) ppm with the correlation coefficient of 0.9989. The molar absorptivity the stoichiometry of extracted complex is found to be 1:2. the proposed method is very sensitive and selective.
This research study the effect of surface modification and copper (Cu) plating carbon fiber (CF) surface on the thermal stability and wettability of carbon fiber (CF)/epoxy (EP) composites. The TGA result indicates that the thermal-stability of carbon fiber may be enhanced after Cu coating CF. TGA curve showed that the treatment temperature was enhanced thermal stability of Ep/CF, this is due to the oxidation during heating. The Cu plating increased the thermal conductivity, this increase might be due to reduce in contact resistance at the interface due to chemical modification and copper plating and tunneling resistance.
The increase of surface polarity after coating cause decreas
... Show MoreThe aim of the research is to determine the impact of profit management practices on the quality of profits through the use of flexibility in determining accounting methods and practices profit information is one of the most important information that concerns current users in general and observing users in particular. Some corporations managements manipulate the results of the company's profit or loss (income statement) and financial position statement with multiple reasons, including capital market motivations to raise their share prices in the stock market and attract investors, and on the other hand the motives of funding and borrowing loans, and the use of the flexibility in accounting policies and estimates to change the in
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The aim of the research is to measure the effect of changing the exchange rate on bank loans, and in order to achieve this goal, the (official exchange rate) was chosen as an independent variable and its effect was studied on the dependent variable, which is bank credit. Commercial Gulf, Baghdad, A Shore International for Investment (and the financial indicators (growth rate of loans) and the statistical program (Eviews 12) were used to measure the impact of the exchange rate change on the bank credit of banks, the research sample for the period 2012-2022, and the research reached a group Among the conclusions, the most important of which is that the
... Show MoreIn present study the effect of soil extracts of different types of soil on ability of two clinical isolates, Pseudomonas aeruginosa and Staphylococcus aureus to form biofilm. The extract of soil was done by using sterile phosphate buffer saline and analyzed by Fourier Transform Infrared Spectroscopic (FTIR). Spectrophotometric method was used to check ability of the studied isolated bacteria to form biofilm on polystyrene microtiter plates. The data of FTIR showed very little difference was observed among extracts of three types of soil (soil contaminated with hydrocarbons; garden soil collected from gardens of al-jadrea, Baghdad and containers soil), but the highest difference was observed in the extract obtained from peat moss clay soil.
... Show MoreBackground: Thermocycling simulates the temperature dynamics in the oral environment. This in vitro study done to measure and compare the effect of thermocycling on the shear bond strength of stainless steel and sapphire brackets bonded to human enamel teeth using light cured orthodontic adhesive and debonded at various time, and to measure adhesive remnant index after debonding. Materials and Methods: one-hundred-twenty extracted upper first premolars for orthodontic reason were used in this study; depending on weather thermocycled or not, the sample was divided into two main groups, then within each group 30 teeth were used for stainless-steel brackets (Bionic®) and for sapphire brackets (Pure®). Both groups were subdivided into three
... Show MoreThe Sebkha is considered the evaporative geomorphological features, where climate plays an active role. It forms part of the surface features in Mesopotamia plain of Iraqi, which is the most fertile lands, and because of complimentary natural and human factors turned most of the arable land to the territory of Sebkha lands. The use satellite image (Raw Data), Landsat 30M Mss for the year 1976 Landsat 7 ETM, and the Landsat 8 for year 2013 (LDCM) for the summer Landsat Data Continuity Mission and perform geometric correction, enhancements, and Subset image And a visual analysis Space visuals based on the analysis of spectral fingerprints earth's This study has shown that the best in the discrimination of Sebkha Remote sensing techniques a
... Show MoreThe research included five sections containing the first section on the introduction o research and its importance and was addressed to the importance of the game of gymnastic and skilled parallel bars effectiveness and the importance of biochemical variables, either the research problem that there is a difference in learning this skill and difficulty in learning may be one of the most important reasons are falling and injury Has a negative impact on the performance and lack of sense of movement of is one of the obstacles in the completion of the skill and the goal of research to design a device that helps in the development of biochemical changes to skill of rear vault dismount with one-half twist on parallel bars in gymnastics . And the n
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