This work was conducted to study the coefficient of performance for solar absorption refrigeration by using direct solar energy using aqueous ammonia 0.45 mass fraction (ammonia – water).The experiments were carried out in solar absorption system .The system consisted of solar collector generator (0.25 m × 0.25 m × 0.04m) and condenser cooled by a water bath followed by liquid receiver and evaporator. The results showed that the maximum generator temperature was (92° - 97°) during June 2009, and the minimum evaporator temperature was (5°C - 10°C) for aqua ammonia system.. It was, also, found that the coefficient of performance, cooling ratio and amount of cooling obtainable increased with increasing maximum generator temperature and pressure. While the minimum evaporator temperature and concentration decreased with increasing maximum generator temperature and pressure. The coefficient of performance was (0.1096 - 0.2396).
This work is an experimental investigation for single basin-single slope solar still coupled with an evacuated tube solar collector. The work is carried out under the climatic conditions of Baghdad city (33.2456º North and East latitude, 44.3337º longitude) through certain days of the months of the year 2019 to study the impact of using evacuated tube solar collector on the daily productivity and efficiency under the outdoors climatic conditions. It was found that using the evacuated tube solar collector increase daily productivity from 2.175 kg/ to 2.95 kg/ for 9 hours (35.63 %) for clear days, also an enhancement about 10.97 % in daily efficiency.
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يرغب المرء أن يعيش في منزل يعبر عن اصالة تصميمه ذا اهداف جمالية كحاجته الى تحقيق الأهداف العملية. وعليه فمن الأهمية بمكان ان يشارك أصحابه مع المعنيين[1] بشؤون التصميم... وهنا ارتأت الباحثة ان تقوم بدراسة علمية حديثة حول ورق الجدران ثلاثي الابعاد وتوظيفة في غرفة المعيشة, وباسلوب عصري حديث يجمع بين جمالية التصميم والحداثة , إضافة الى تناول الإضاءة لما لها من دور في ابراز معالم وتفاصيل الأثاث
... Show MoreAbstract. Silver, Indium Selenium thin film with a thickness (5001±30) nm, deposited by thermal evaporation methods at RT and annealing3temperature (Ta=400, 500 and 600) K on a substrate of glass to study structural and optical properties of thin films and on p-Si wafer to fabricate the AgInSe2/p-Si heterojunction solar cell. XRD analysis shows that the AgInSe2 (AIS) deposited film at RT and annealing3temperature (Ta=400, 500 and 600) K have polycrystalline structure. The average grain size has been estimated from AFM images. The energy gap was estimated from the optical transmittance using a spectrometer type (UV.-Visible 1800 spectra photometer). From I-V characterization , the photovoltaic parameters such as, open-circuit voltage, short
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While practicing of International business particularly that centered on foreign direct investment, let on one side, to achieving objectives of transnational corporations specially that represented in continuous pursue to improving its cash flows and maximization of stockholders wealth which is considered the most important objective to the transnational corporations, but in the same time its lead, on other side, to increasing the foreign exchange risk exposuring these corporations. So, the transnational corporations (TNCs) struggling to make strategies which are dealing in smart way, with this risk and its management in way that enable to avoiding risk comple
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In this paper, the penetration of the stone column was investigated in order to get the minimum length of the stone column above which the increase in length has little advantage. The effect of using different materials in column are also studied. The material used is granular of different angle of internal friction (). The results of the investigation indicated that the effect of stone column remains constant when the ratio of the thickness of the soft clay layer to the stone column’s diameter is more than 15. The results also indicated that a pronounced effect is obtained when the angle of internal friction of the stone column material is increased.
Prepared zeolite type A was used for theremoval of cesium ions from aqueous solution. The experimental data were analyzed by Langmuir, Freundlich isotherms. Various parameters, such as contact time, zeolite weight, pH, and initial concentration, were studied. The results indicated that the highest removal efficiency was95.53% at (2h time, 0.04 g weight, and pH=6.8). The results also showed that the Freundlic model fits well with the experimental results and is better than the Langmuir model.
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This paper aims to review the intellectual to the most important thought leaders administrative and strategic They both (Henry Fayol and Michelle Porter), who forward a lot of ideas that have helped countries in the advancement and progress their economies , has been drawing literature theoretical common border in Contributions ( Fayol ) philosophical and between applications ( Porter ), which reversed strategies of the three ( the leadership of the cost, differentiation, and focus ), so browse search how to apply and use the principles of Fayol in the implementation of strategies competitiveness of Porter, and stems from a problem ( ( to what extent a reflection of the principles ( Fayol) fourteen strategies (Porter ) competitiv
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