منابع مشابه
simulation and experimental studies for prediction mineral scale formation in oil field during mixing of injection and formation water
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. ...
the underlying structure of language proficiency and the proficiency level
هدف از انجام این تخقیق بررسی رابطه احتمالی بین سطح مهارت زبان خارجی (foreign language proficiency) و ساختار مهارت زبان خارجی بود. تعداد 314 زبان آموز مونث و مذکر که عمدتا دانشجویان رشته های زبان انگلیسی در سطوح کارشناسی و کارشناسی ارشد بودند در این تحقیق شرکت کردند. از لحاظ سطح مهارت زبان خارجی شرکت کنندگان بسیار با هم متفاوت بودند، (75 نفر سطح پیشرفته، 113 نفر سطح متوسط، 126 سطح مقدماتی). کلا ...
15 صفحه اولformation and evolution of regional organizations: the case study of the economic cooperation organization (eco)
abstract because of the many geopolitical, geo economical and geo strategically potentials and communicational capabilities of eco region, members can expand the convergence and the integration in base of this organization that have important impact on members development and expanding peace in international and regional level. based on quality analyzing of library findings and experts interv...
15 صفحه اولFormation Kinetics of Structure H Gas Hydrate
This paper investigates the kinetics of structure H (sH) formation kinetics above and below the structure I (sI) formation equilibrium curve at temperatures of between 2°C and 6°C. Methane was used as a help gas and methylcyclohexane (MCH) was used as sH former. It was concluded that in the points above the sI formation equilibrium curve, at the first, the sI forms, and then converts to sH be...
متن کاملMathematical methods of data processing in the formation and evaluation of sectoral structure in agricultural enterprises
The sectoral structure of most agricultural enterprises is unbalanced and uncoordinated, which underlies the need in deepened research of its improvement. This paper is dedicated to the formation and evaluation of the sectoral structure with the use of mathematical methods of data processing. Mathematical economic modeling based on optimization and simulation models has been applied for the for...
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ژورنال
عنوان ژورنال: Proceedings of the National Academy of Sciences
سال: 1987
ISSN: 0027-8424,1091-6490
DOI: 10.1073/pnas.84.24.8793