1,251 research outputs found

    Influence of asphaltene inhibitors on asphaltene deposition in the porous media

    Get PDF
    351-355This article deals with organic asphaltene deposition in the reservoir rock, for crude oil having high asphaltene content and high apparent viscosity. The crude oil is characterized using thermal analysis through the thermogravimetric method. Crude oil is blended with heptane and flooded through the formation core at 55°C and 200-1200 psi pressure. With the rise in flow pressure, asphaltene precipitation became more significant with about four hundred times fall in the initial flow rate (flow rate at 200 psi) of crude oil at 1200 psi pressure. Phthalic acid and turpentine oil are used as asphaltene inhibitors for this crude oil. These asphaltene inhibitors are easy to procure, required less dosage for asphaltene dissolution and are relatively less toxic as compared to the other organic solvents used frequently as asphaltene inhibitor in oil industries. The asphaltene inhibitors are injected into the crude oil and flowed through the pores of the core. It is found that the crude oil treated with phthalic acid resulted in 88.23% increment its flow rate as compared to the turpentine oil, suggesting significant organic asphaltene dissolution in the formation rock

    Optimasi Portofolio Resiko Menggunakan Model Markowitz MVO Dikaitkan dengan Keterbatasan Manusia dalam Memprediksi Masa Depan dalam Perspektif Al-Qur`an

    Full text link
    Risk portfolio on modern finance has become increasingly technical, requiring the use of sophisticated mathematical tools in both research and practice. Since companies cannot insure themselves completely against risk, as human incompetence in predicting the future precisely that written in Al-Quran surah Luqman verse 34, they have to manage it to yield an optimal portfolio. The objective here is to minimize the variance among all portfolios, or alternatively, to maximize expected return among all portfolios that has at least a certain expected return. Furthermore, this study focuses on optimizing risk portfolio so called Markowitz MVO (Mean-Variance Optimization). Some theoretical frameworks for analysis are arithmetic mean, geometric mean, variance, covariance, linear programming, and quadratic programming. Moreover, finding a minimum variance portfolio produces a convex quadratic programming, that is minimizing the objective function ðð¥with constraintsð ð 𥠥 ðandð´ð¥ = ð. The outcome of this research is the solution of optimal risk portofolio in some investments that could be finished smoothly using MATLAB R2007b software together with its graphic analysis

    Search for heavy resonances decaying to two Higgs bosons in final states containing four b quarks