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61.
Micromechanical cohesion force measurements to determine cyclopentane hydrate interfacial properties
Aman ZM Joshi SE Sloan ED Sum AK Koh CA 《Journal of colloid and interface science》2012,376(1):283-288
Hydrate aggregation and deposition are critical factors in determining where and when hydrates may plug a deepwater flowline. We present the first direct measurement of structure II (cyclopentane) hydrate cohesive forces in the water, liquid hydrocarbon and gas bulk phases. For fully annealed hydrate particles, gas phase cohesive forces were approximately twice that obtained in a liquid hydrocarbon phase, and approximately six times that obtained in the water phase. Direct measurements show that hydrate cohesion force in a water-continuous bulk may be only the product of solid-solid cohesion. When excess water was present on the hydrate surface, gas phase cohesive forces increased by a factor of three, suggesting the importance of the liquid or quasi-liquid layer (QLL) in determining cohesive force. Hydrate-steel adhesion force measurements show that, when the steel surface is coated with hydrophobic wax, forces decrease up to 96%. As the micromechanical force technique is uniquely capable of measuring hydrate-surface forces with variable contact time, the present work contains significant implications for hydrate applications in flow assurance. 相似文献
62.
Ange Mouithys-Mickalad Nuria Martin Tome Thomas Boogaard Arpita Chakraborty Didier Serteyn Kees Aarts Aman Paul 《Molecules (Basel, Switzerland)》2021,26(14)
Black soldier fly larvae (BSFL)-derived proteins are gaining popularity as sustainable pet food ingredients. According to the literature, these ingredients have strong antioxidant and antimicrobial activities. Due to the ability of BSFL protein derivatives to donate hydrogen atoms and/or electrons to counterpoise unstable molecules, they could possibly help in the prevention of osteoarthritis. During this study, the antiarthritic potential of BSFL protein derivatives was evaluated using the following assays: (1) proteinase inhibition, (2) erythrocyte membrane stability, (3) reactive oxygen species (ROS) production by activated macrophages, (4) ROS production by monocytes, and (5) cellular toxicity. Additionally, the glucosamine content of these ingredients was also evaluated. Chicken meal is commonly used in pet food formulations and was used as an industrial benchmark. The results obtained during this study demonstrated the strong antiarthritic potential of BSFL protein derivatives. We found that BSFL protein derivatives are not only useful in preventing the development of arthritis but could also help to cure it due to the presence of glucosamine. We also found that chicken meal could contribute to the development of arthritis by increasing ROS production by monocytes. 相似文献
63.
A new class of generalized backward doubly stochastic differential equations (GBDSDEs in short) driven by Teugels martingales associated with Lévy process are investigated. We establish a comparison theorem which allows us to derive an existence result of solutions under continuous and linear growth conditions. 相似文献
64.
A comprehensive review, >100 references, on organotin(IV) complexes of the carboxylic acid derivatives are presented with
special reference to their methods of synthesis, spectroscopic and structural studies and their biological activities. The
structures of these complexes are discussed on the basis of IR, multinuclear (1H-, 13C- and 119Sn-) NMR. 相似文献
65.
66.
H. Aman 《Laser Physics》2012,22(8):1286-1291
In this paper the construction of a mechanically Q-switched diode side pumped Nd:YAG laser system is described. It consists of a 50 cm long plane-plane resonator Q-switched with a combination of a rotating prism and a mirror. With an optical to optical efficiency of 25% Q-switched pulses (@1064) of 48 mJ and 8 ns are obtained at a rep-rate of 30 Hz with an output in near TEMoo mode. At a peak power of 6 MW the M 2 value is found to be 1.92. The laser is frequency doubled and then tested on a 50 ??m thick tantalum foil which results in circular holes of diameter 13 ??m in it. 相似文献
67.
Haroon Aman 《Journal of Russian Laser Research》2012,33(6):531-535
We present a design for a compact laser-diode-end-pumped Nd:YAP/Cr:YAG q-switched laser in a plano?Cconcave cavity configuration. With an optical-to-optical efficiency of 35%, this laser provides an average output of 1.2 W with 13 mJ at 1080 nm. After that, the laser is frequency doubled by replacing the output coupler with a flat KTP crystal to achieve an output of 8 mJ in 8 ns at 540 nm. At a peak power of 1 MW, the laser emits linearly polarized output with an average power of 800 mW. The calculated M2 value is 1.3, the output is very stable, and the laser operates in the TEM00 mode. 相似文献
68.
69.
In this work, we have investigated the thermal radiation power spectra of 1D photonic crystal structure containing Si and SiO2 having an absorbing substrate with truncated thickness. The thermal radiation power spectra are determined by the means of a theoretical model based on a transfer matrix for both normal and oblique incidence together with Kirchhoff’s second law. It is observed that thermal radiation power spectra show strong dependence on truncation parameter and incident angle. 相似文献
70.