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141.
Muhammad Zafar Mushtaq Ahmad Shazia Sultana Lubna Adnan Amin Hafiz Muhammad Naseer Zafar Jamal Sheikh Zain Ul Abidin Sajid Mehmood Amir Shehzad Khan 《Microscopy research and technique》2019,82(5):550-557
The use of quality control tool for authentication of Jadwar (Delphinium denudatum Wall. ex Hook.f. & Thomson), a folk herbal drug used for the treatment of different ailments, was studied. People face problems of adulteration for this drug at global, regional, national and local levels. Two different plant species are commercially marketed in the Indo‐Pak Subcontinent under the same trade name of Jadwar. One is D. denudatum Wall. ex Hook.f. & Thomson and the other is Aconitum heterophyllum Wall. ex Royle. To focus on this problem, a marketable available drug sample of Jadwar was authenticated by using basic microscopy tools (LM) and advanced chemo‐taxonomic markers. Authentication, quality and standardization of this drug was achieved using morphology, organoleptography, UV and IR analyses, scanning electron microscopy of pollen and anatomical investigations. The techniques used for authentication marked the clear difference between the studied plants. Microscopic studies, chemotaxonomic investigation and other techniques used in this project provided the basis for the authentication of this species. 相似文献
142.
Jamal A. Anabtawi 《Petroleum Science and Technology》1993,11(10):1409-1424
Coker light gas oil (LGO) derived from Athabasca bitumen was hydrotreated in a fixed bed reactor using two commercial NiO-MoO3/Al203 catalysts. The effect of temperature on product quality was investigated in a pilot plant between 330 and 390 °C at 12.4 MPa, space velocity of 0.5 Ir1 and 700 liter of hydrogen per liter of coker LGO (L/L). The product quality was monitored by I3C NMR spectroscopy, elemental analysis, density and distillation techniques.
The data showed that coker LGO can be hydrotreated using nickel-molybdenum catalysts at 350 °C, 0.5 h1, 12.4 MPa and 700 L/L to meet the diesel product specifications, namely, 0.5 wt % sulfur, 20% aromatics and cetane index of 40. The cetane index improvement and aromatic saturation, which are affected by thermodynamic equilibrium at temperature higher than 370 °C, could reach 29 and 86% respectively. The cetane improvement was attributed to aromatic saturation and hydrocracking with hydrogen consumption ranging from 215-340 L/L. The Ketjenfine KF-840 catalyst was found slightly better performance than Procatalyse HR-348 catalyst. 相似文献
The data showed that coker LGO can be hydrotreated using nickel-molybdenum catalysts at 350 °C, 0.5 h1, 12.4 MPa and 700 L/L to meet the diesel product specifications, namely, 0.5 wt % sulfur, 20% aromatics and cetane index of 40. The cetane index improvement and aromatic saturation, which are affected by thermodynamic equilibrium at temperature higher than 370 °C, could reach 29 and 86% respectively. The cetane improvement was attributed to aromatic saturation and hydrocracking with hydrogen consumption ranging from 215-340 L/L. The Ketjenfine KF-840 catalyst was found slightly better performance than Procatalyse HR-348 catalyst. 相似文献
143.
144.
Filali Hajar Riffi Jamal Aboussaleh Ilyasse Mahraz Adnane Mohamed Tairi Hamid 《Neural Processing Letters》2022,54(1):387-404
Neural Processing Letters - Facial expression is an important aspect to recognize emotions between humans. However, this task remains difficult for machines. Several approaches have been developed... 相似文献
145.
Khan Lal Said Khan Majid Jamal Sajjad Shaukat Amin Muhammad 《Multimedia Tools and Applications》2022,81(23):33591-33611
Multimedia Tools and Applications - One of the most critical aspects of this technologically progressive era is the propagation of information through an unsecured communication channel. The... 相似文献
146.
Izzet Altun Jingjie Hu Hassan Albadawi Zefu Zhang Marcela A. Salomao Joseph L. Mayer Leila Jamal Rahmi Oklu 《Advanced materials (Deerfield Beach, Fla.)》2020,32(52):2005603
Vascular embolization is a life-saving minimally invasive catheter-based procedure performed to treat bleeding vessels. Through these catheters, numerous metallic coils are often pushed into the bleeding artery to stop the blood flow. While there are numerous drawbacks to coil embolization, physician expertise, availability of these coils, and their costs further limit their use. Here, a novel blood-derived embolic material (BEM) with regenerative properties, that can achieve instant and durable intra-arterial hemostasis regardless of coagulopathy, is developed. In a large animal model of vascular embolization, it is shown that the BEM can be prepared at the point-of-care within 26 min using fresh blood, it can be easily delivered using clinical catheters to embolize renal and iliac arteries, and it can achieve rapid hemostasis in acutely injured vessels. In swine arteries, the BEM increases cellular proliferation, angiogenesis, and connective tissue deposition, suggesting vessel healing and durable vessel occlusion. The BEM has significant advantages over embolic materials used today, making it a promising new tool for embolization. 相似文献
147.
Not only are microwaves notorious in food heating, but they exhibit interesting properties in different domains including chemical engineering. Their ability to concentrate heat transfer inside dielectric materials enhances process efficiency and permits high heating rates. Nonetheless, their effect on reactions is still controversial. While some researchers believe in non-thermal effects due to the efficient conversion of microwave energy to enhance reactions without heat dissipation, others assert that microwave frequencies are not high enough to excite molecular bonds. In this study, paper cups pyrolysis is achieved in electrical and microwave TGA using two heating modes. The effect of microwaves on the kinetics of paper cups pyrolysis is shown to depend on the heating regime: at a moderate heating rate, microwave pyrolysis started at a lower temperature, while the pyrolysis in the electrical and microwave TGA have similar kinetic parameters at high heating conditions. This difference is linked with reaction mechanisms. At moderate heating conditions, cellulose decomposes first to an intermediate compound then to final products. The intermediate has a short reaction time and interacts with the microwave. Hence, hot spots at the molecular scale are generated in a short amount of time below the detectable limits of existing temperature measurements media. At a high heating rate, the decomposition of cellulose is direct and no effect is observed. 相似文献
148.
149.
Javed A. Farooqi Sajid Jamal I. Ahmad 《Journal of the American Oil Chemists' Society》1985,62(12):1702-1703
Seed oil ofSemecarpus kurzii was found to contain 10.5% of 9-hydroxy-cis-12-enoic (isoricinoleic) acid along with the usual fatty acids. The identification of the hydroxy acid was made on the basis
of chromatographic, spectroscopic and chemical methods, with isoricinoleic acid used as the reference standard. 相似文献
150.
Sajid Jamal Javed A. Farooqi M. S. Ahmad Abdul Mannan 《Journal of the science of food and agriculture》1987,39(3):203-206
The seed oils of Acacia mollissima, A. torta, A. lenticularis and A. nilotica are found to contain 6.2, 5.3, 4.7 and 3.1%, respectively, cor-onaric acid in addition to other fatty acids. The structure of coronaric acid was established by chemical and physical methods using Chrysanthemum coronarium seed oil and its derived coronaric acid as the reference sample. 相似文献