during recent years oil products has decreased because of growing population and increasing demand to oil products and decreasing of crude oil extraction at compare to export. however, to achieve suitable levels of production, the use of improved technologies should be considered. another way to prevent the evaporation and leakage from oil storage tanks and their products are using of storage t...

این پژوهش با الهام گرفتن از نتایج یک طرح مطالعاتی کاربردی، رویکرد سلسله­‌مراتبی جهت پیگیری فرایند توسعه تأمین‌کنندگان و حمایت تصمیمات موجود در هر مراحل آن ارائه‌ می‌کند. ابتدا، زمینه‌های تأمین نیازمند سپس واجد شرایط هریک زمینه‌ها به کمک تصمیم‌گیری چندشاخصه بهترین-بدترین مشخص می‌گردند. معیارهای شناسایی نیز مرور مطالعات پیشین بهره‌گیری نظرات خبرگان حوزه‌ی خرید استخراج‌شده‌اند. درنهایت، مدل ریاضی ...

Experiments were conducted to study the performance of circular and square tank surface aerators on the oxygen transfer coefficient and to a limited extent on power requirements. All the tanks are geometrically similar except for their shapes. They consist of a rotor of diameter, D, fixed with six flat blades rotating with a speed, N, in pure waters of viscosity, υ, at room temperature. A simul...

Household water in Oman, as well as in other countries in the region, is stored in tanks placed on house roofs that can be subjected to physicochemical factors which can promote microbial growth, including pathogens and opportunistic pathogens which pose health risks. Water samples were collected from 30 houses in a heavily populated suburb of Muscat. The tanks used were either glass reinforced...

Neutron diffraction analysis was employed to measure residual stresses near welds in used anhydrous ammonia nurse tanks. Tensile residual stresses contribute to stress corrosion cracking of nurse tanks, which can cause tanks to release toxic ammonia vapor. The analysis showed that tensile residual stresses were present in the tanks measured, and the magnitudes of these stresses approached the y...

Settling-thickening tanks are used to achieve separation of the liquid and solid fractions of faecal sludge (FS). They were fi rst developed for primary wastewater treatment, and for clarifi cation following secondary wastewater treatment, and it is the same mechanism for solids-liquid separation as that employed in septic tanks. Settling-thickening tanks for FS treatment are rectangular tanks,...

The primary mission of Oak Ridge National Laboratory (ORNLj during World War I1 was the processing of pure plutonium metal in support of the Manhattan Project. By-products of this process include radioactive cesium-1 37 and strontium-90. Between 1943 and 1951, the Gunite and Associated Tanks (GAAT) at ORNL were built to collect, neutralize, and store these byproducts. Currently, twelve gunite t...

Dengue occurs throughout the year in Hanoi, Vietnam, despite winter low temperatures <10°C. During July 2010 to March 2012, we surveyed monthly for Aedes larvae and pupae in 120 houses in 8 Hanoi districts. Aedes albopictus preferred discarded containers in summer and pupal density drastically decreased in winter. Aedes aegypti preferred concrete tanks and this preference increased in winter. E...