Gas hydrate formation is considered one of the major problems facing the oil and gas industry as it poses a significant threat to the production, transportation and processing of natural gas. These solid structures can nucleate and agglomerate gradually so that a large cluster of hydrate is formed, which can clog flow lines, chokes, valves, and other production facilities. Thus, an accurate predictive model is necessary for designing natural gas production systems at safe operating conditions and mitigating the issues induced by the formation of hydrates. In this context, a thermodynamic model for gas hydrate equilibrium conditions and cage occupancies of N2 + CH4 and N2 + CO4 gas mixtures at different compositions is proposed. The van der Waals-Platteeuw thermodynamic theory coupled with the Peng-Robinson equation of state and Langmuir adsorption model are employed in the proposed model. The experimental measurements generated using a cryogenic sapphire cell for the pressure and temperature ranges of (5-25) MPa and (275.5-292.95) K, respectively, were used to evaluate the accuracy of this model. The resulting data show that increasing nitrogen mole percentage in the gas mixtures results in decreasing of equilibrium hydrate temperatures. The deviations between the experimental and predictions are discussed. Furthermore, the cage occupancies for the gas mixtures in hydrate have been evaluated. The results demonstrate an increase in the cage occupancy for both the small and large cavities with pressure.
A numerical and experimentally investigation for two types of winglets (spiroid and blended), which are used to reduce the induced drag caused by the trailing vortices were presented and discussed in this work. The SOLIDWORK 2016 was used to model a rectangular wing geometry of NACA2415 cross-sectional airfoil with blended and spiroid airfoils (2415 and 0012). The steady, incompressible N.S equations with standard (
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By March 2020, a pandemic had been emerged Corona Virus Infection in 2019 (COVID-19), which was triggered through the sensitive pulmonary syndrome (SARS disease corona virus- 2 (SARS COV-2). Overall precise path physiology of SARS COV-2 still unknown, as does the involvement of every element of the acute or adaptable immunity systems. Additionally, evidence from additional corona virus groups, including SARS COV as well as the Middle East pulmonary disease, besides that, fresh discoveries might help researchers fully comprehend SARS CoV-2. Toll-like receptors (TLRs) serve a critical part in both detection of viral particles as well as the stimulation of the body's immune response. When TLR systems are activated, pro-inflammatory cy
... Show Moreكان لنهاية الحرب الباردة وعولمة العالم على وفق رؤية كونية تتجاوز حدود ومفاهيم السيادة الوطنية والقومية الاثر الواضح في ترتيب العلاقات الدولية , واصبحت تلك العلاقات تدور حول محورين الاول .. هو الاعتماد المتبادل بين الدول من اجل الوصول الى خطوط مشتركة للمصالح المختلفة بين هذه الدول . والآخر.. هو تبعية الدول الضعيفة للدول القوية لافتقار الاولى توفير الحاجيات الى مواطنيها . هذا يشير الى نشأة علا
... Show Morethe structrual and mechanical properties of thin Ni films of different thicknesses deposited on coring glass substrate using lonbeam sputtering(IBS) technique under vacuum torr have been studied the TEM and electron
The city of Derna has distinctive architectural and architectural features, like other Arab and Islamic cities in the Arab West and North Africa. Its markets and shops have taken many different forms and structural forms within the urban fabric of the central commercial zone. The meeting between the various commercial and handicraft jobs and consumers within a spatial area starting with the old markets of the dark market and the agency of the harvest and vegetable market and the mosque of the old and the square of the mosque and the Red Square and the square Kharazin. It then grew linearly towards commercial hubs that were associated with the city's expansion axes. Old markets represent the architectural and planning heritage associated
... Show More The research aims to (identify the applications of pedagogy in art education), the research community included, art education for the primary stage, so the community consisted of (8) main areas in art education, either the research sample was chosen, two main areas (objectives, and content), and included the research methodology (descriptive and analytical), the researcher built the research tool represented (the validity form of the tool) and presented to a group of experts to indicate its validity as well as to measure its stability, To show the results, the researcher used the percentage, and the researcher recommended - modifying the curriculum every period of time, such as every four years, others
SAGD is a thermal recovery process in which steam oil ratio, SOR, is a key parameter that can affect the economic outcome of the process. Reservoirs with underlying or overlying lean bitumen present challenges for SAGD as they can act as a heat sink. Water has higher heat capacity than the bitumen and thus requires more steam to heat up the reservoir leading to higher SOR. The potential outcome of operating SAGD in these conditions may be lower bitumen rate and higher steam injection rate, both of which affect plant throughput and thus the economic matrix of SAGD. This paper looks at the performance of SAGD process in the presence of top lean bitumen. It will examine the theoretical CSOR that is needed to produce the bitumen with different
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In today's world, most business, regardless of size, believe that access to Internet is imperative if they are going to complete effectively. Yet connecting a private computer (or a network) to the Internet can expose critical or confidential data to malicious attack from anywhere in the world since unprotected connections to the Internet (or any network topology) leaves the user computer vulnerable to hacker attacks and other Internet threats. Therefore, to provide high degree of protection to the network and network's user, Firewall need to be used.
Firewall provides a barrier between the user computer and the Internet (i.e. it prevents unauthor
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