determination of uranium in natural water and complex solutions using ion exchange chromatography: a combined procedure using ion exchange chromatography and uv-vis spectrophotometry techniques has been developed to measure uranum in natural water and complex solutions. after conditicing , one hundred milli liters of sample solutions have been passed through an ion exchange column,pachked with ...

many mobile and off-grid devices include electronics and other electrical consumers like servo drives, which need a quite low supply power. since the price for photovoltaic modules drops continuously, photovoltaic power supply is interesting in more and more applications. in solar powered systems, a battery is needed to store energy for the night and cloudy periods. the power electronics of suc...

the study of air infiltration into the buildings is important from several perspectives that may be noted to energy and design of hvac systems, indoor air quality and thermal comfort and design of smoke control systems. given the importance of this issue, an experimental and numerical study of air infiltration through conventional doors and windows has been explored in iran. to this end, at fir...

در سال های اخیر به دلیل افزایش دمای متوسط کره زمین، بشر به دنبال روش های جایگزین برای تامین توان الکتریکی مورد نیاز خود بوده و همچنین در اکثر نقاط جهان سوزاندن سوخت های فسیلی در نیروگاه های حرارتی به عنوان مهم ترین روش تولید توان الکتریکی مطرح بوده است. به دلیل توجه به مسایل زیست محیطی، استفاده از منابع انرژی تجدید پذیر در سال های اخیر شدت یافته است. نیروگاه های بادی به عنوان یک منبع تولید توان...

abstract: mineral scaling in oil and gas production equipment is one of the most important problem that occurs while water injection and it has been recognized to be a major operational problem. the incompatibility between injected and formation waters may result in inorganic scale precipitation in the equipment and reservoir and then reduction of oil production rate and water injection rate. ...

power transformers are important equipments in power systems. thus there is a large number of researches devoted of power transformers. however, there is still a demand for future investigations, especially in the field of diagnosis of transformer failures. in order to fulfill the demand, the first part reports a study case in which four main types of failures on the active part are investigate...

Abstract: In traditional generation systems, energy from fuel is simply converted into electrical energy, while in the combined heat and power (CHP) systems, fuel energy, in addition to generating electricity, also generates thermal energy. Therefore, the efficiency of these systems is considerably higher than traditional systems, and this justifies the need for CHP systems. The emergence of CH...

growing demands and requires of high data rate systems cause significant increase of high frequency systems for wideband communication applications. as mixers are one of the main blocks of each receivers and its performance has great impact on receiver’s performance; in this thesis, a new solution for ku-band (12-18 ghz) mixer design in tsmc 0.18 µm is presented. this mixer has high linearity a...