Formation and accumulation of polycyclic aromatic hydrocarbons (PAHs) are responsible major topical issues related to the conversion petroleum vacuum gas oils (VGOs) in transportation fuels through hydrocracking process. To achieve an efficient management these hydrocarbons, a detailed semi-quantitative description PAHs contained VGOs was provided by three-dimensional off-line analytical approa...

BACKGROUND COPD-diagnosis is confirmed by post-bronchodilator (BD) spirometry. However, epidemiological studies often rely on pre-BD spirometry, self-reports, or medical records. This population-based study aims to determine COPD-prevalence based on four different operational definitions and their level of agreement, and to compare associations between COPD-definitions and risk factors. METHO...

NREL's thermochemical biomass conversion research is focused on ex-situ upgrading of fast-pyrolysis (FP) vapors as an efficient route to completely biogenic pyrolysis-based fuel precursors, fuels, and value-added chemicals depending catalyst process conditions. A near term pathway being developed uses these liquids for co-processing with petroleum feedstocks assess carbon incorporation in hydro...

The catalytic performance of a hydrocracking bifunctional catalyst and consequently its activity loss depend on the balance between metal (M) acid (A) functions. Commonly, function is reputed to stabilize should therefore alleviate deactivation. In order test this hypothesis, study aimed assess impact oxide (MoO3) content deactivation vacuum gasoil (nickel-molybdenum sulfide dispersed carrier c...

Catalyst deactivation is usually indispensable, although the rate at which it occurs varies greatly. At first, this article discusses the causes of deactivation in a commercial hydrocracking unit called Isomax. Then, a 5-lump kinetic model including catalyst decay function for hydrocracking of vacuum gas oil in a commercial plant is proposed. The model considers vacuum gas oil (VGO) having boil...

In this article, the improved space-time conservation element and solution element (CESE) method are used to simulate the dynamic treatment of the hydrocracking reactor. The dynamic model consists of four lumps: vacuum gas oil (VGO), middle distillate, naphtha, and gas which is dissolved by this method. The offered method can solve the partial differential equations caused by the reactions insi...

Background and Aim: Knowledge about the root canal system variations is crucial for successful endodontic treatment. This study aimed to examine the applicability of cone-beam computed tomography (CBCT) as a substitute for the gold-standard tooth clearing technique in identification of internal anatomical variations of mandibular incisors. Materials and Methods: This in-vitro study evaluated 6...

Abstract Study question Is there a relationship between the concentration of βhCG hormone in maternal blood, embryo morphokinetics and clinical outcome? Summary answer is related to trophoectoderm quality, abortion rate live birth rate, but not What known already Measurement has been widely used for early pregnancy detection after assisted reproduction treatments. Shortly implantation, trophobl...

introduction   capability evaluation can be considered as a basic strategy for land use becausethe development synchronous with the naturecan be achieved by using identifying and assessing of the ecological characteristics of the area. agricultural land suitability classification based on indigenous knowledge is vital to land-use planning (ecological capacity evaluation). execution of developme...