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61.
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.
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.
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   
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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.
气泡与弹性边界的相互作用研究   总被引:1,自引:0,他引:1  
从气泡与弹性边界相互作用基本现象入手, 基于势流理论, 建立气泡与弹性边界相互作用的数值模型, 计及浮力与表面张力, 模拟弹性介质附近单个气泡的动态特性, 通过气泡周围压力场的分布来讨论蘑菇状气泡的成因, 数值结果与已有实验结果吻合良好. 讨论两个气泡与弹性边界的相互作用, 并通过与Robinson 和Blake的实验结果对比, 验证数值模型的正确性. 数值模拟发现, 浮力、弹性系数和密度比是影响气泡动态特性的重要特征参数.   相似文献   
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