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531.
Hadis Askari Farhad Khorasheh Saeed Soltanali Shokoufe Tayyebi 《Egyptian Journal of Petroleum》2019,28(2):225-231
Desulfurization by molten caustic leaching (MCL) at 400–500 °C has been investigated in order to reduce the sulfur content of petroleum coke. Effective parameters on desulfurization of petroleum coke, other than temperature, include alkali to feed (petroleum coke) mass ratio, time and mesh size in the ranges of 0.5–1.5, 1–3 h and 200–600 µm, respectively. In this work, petroleum coke desulfurization conditions using solid KOH have been studied. Maximum petroleum coke desulfurization by MCL method has been obtained by Taguchi L9 design using alkali to feed mass ratio of 1, temperature of 600 °C, time of 2 h and mesh size of 200 µm. The changes in the main groups on the coke surface have been determined using FTIR spectroscopy. In addition, SEM-EDX, TGA and XRD analyses have been used to investigate the changes in coke physical and chemical properties. 相似文献
532.
The shoulder complex, also known as the glenohumeral joint is the most manoeuvrable and one of the most well used joints of the human body. Over time problems can occur with the glenohumeral joint and surrounding muscles, cartilage, tendons and ligaments caused by ageing or by over stressing the shoulder complex. This work examines the design of a new innovative glenohumeral test rig. The test rig was required to imitate the movement of the humerus in the human body and replicate all the ranges of motion, which it can move in when combined with the relevant bones, muscles, ligaments and tendons in the shoulder complex. A variable force also had to be applied to the glenoid in all ranges of motion. Research had to be undertaken in the ranges of motion of the shoulder complex and the forces acting on the glenoid. Concept designs were initially created to mimic specific ranges of motion; adduction, flexion, internal (medial) and external (lateral) rotation for example. The concepts were evolved and combined to develop a test rig that would replicate any axial movement of the shoulder. Research determined the most appropriate manufacturing processes and materials so that the test rig could be manufactured in the material laboratories. 相似文献
533.
Silicon - In this article the preparation of Fe3O4@MCM-41@NH-SO3H, a new sulfonated magnetic mesoporous nanocomposite, is reported. The introduced catalyst is structurally based on MCM-41 as the... 相似文献
534.
Vaferi Kourosh Vajdi Mohammad Nekahi Sanam Nekahi Sahar Sadegh Moghanlou Farhad Azizi Shahla Shahedi Asl Mehdi 《Microsystem Technologies》2023,29(1):141-156
Microsystem Technologies - The problem of generating a high amount of heat in microelectronic equipment should be minimized properly. Allowing systems to run for long periods of time in high... 相似文献
535.
Tabrizi Arvin Taghizadeh Aghajani Hossein Laleh Farhad Farhang 《Protection of Metals and Physical Chemistry of Surfaces》2022,58(2):365-373
Protection of Metals and Physical Chemistry of Surfaces - In this study, a thin chromium layer was applied on pure titanium substrate in a Sargent bath including 250 g/L chromic acid and 2.5 g/L... 相似文献
536.
Studying the Role of Gelation Agents in Gelcasting Non-porous Si3N4 Bodies by Pressureless Sintering
Sharifi Omid Alizadeh Siavash M. Golmohammad Mohammad Golestanifard Farhad 《SILICON》2022,14(16):10447-10457
Silicon - The monomer content in the gelcasting process affects the kinetics of cross-linking reactions which determines the quality of the gel network structure and the final properties of the... 相似文献
537.
Aliakbar Ahmadi Mojgan Ayoubi-Chianeh Mohamad Z. Kassaee Farhad Bayat 《加拿大化工杂志》2023,101(7):4200-4216
The aim of this research is a comparison of the efficiency of six commercially available cyclodextrins (CDs) to improve the solubility and oral bioavailability of atorvastatin calcium (ATV-Ca) and rosuvastatin calcium (ROV-Ca) drugs in aqueous media. Inclusion complexes of both drugs with non-toxic α-CD, β-CD, γ-CD, HP-β-CD, M-β-CD, and maltodextrin were prepared in a 1:1 stoichiometry via the kneading method. To reach the best CD, various experimental and computational analyses were performed including phase solubility, dynamic light scattering (DLS), Fourier transform infrared spectroscopy (FT-IR), X-ray diffraction (XRD), differential scanning calorimetry (DSC), scanning electron microscopy (SEM), atomic force microscopy (AFM), hydrogen-1 nuclear magnetic resonance (1HNMR), carbon-13 nuclear magnetic resonance (13CNMR), and molecular docking calculations. The M-β-CD turned out to be the best substrate for the micro-encapsulation of both drugs. Also, ATV showed a higher tendency than ROV to form inclusion complexes with CDs. Molecular docking studies showed that HP–β–CD and M-β-CD are the most suitable substrates for the formation of inclusion complexes, respectively. Our research showed that the β-CD is not necessarily the most efficient substrate for increasing solubility based on previous reports in the literature; meanwhile, the other employed substrates in this study can show acceptable performances in this regard. According to our results, M-β-CD is the best substrate for the micro-encapsulation of both drugs, which increases their solubility in water. 相似文献