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71.
72.
Random early detection (RED) is an effective congestion control mechanism acting on the intermediate gateways. We describe a new active queue management scheme, Effective RED (ERED) that aims to reduce packet loss rates in a simple and scalable manner. We made a few change to packet drop function of existing RED scheme. The rest of the original RED remains unchanged. We achieve this by making several refinements and by controlling packet dropping function both with average queue size and instantaneous queue size. Simulations demonstrate that ERED achieves a highest throughput and lowest packet drops than RED, Blue, REM, FRED, LDC and SRED. Since ERED is fully compatible with RED, we can easily upgrade/replace the existing RED implementations by ERED.  相似文献   
73.
The catalytic activity of the following samples in the hydroxylation reaction were studied: PPFe 3+ OH/AlSiCr, PPFe 3+ OH/AlSiMg, PPFe 3+ OH/Al 2 O 3 , and per-FTPhPFe 3+ OH/Al 2 O 3 . PPFe 3+ OH/AlSiMg-catalyzed methane hydroxylation yielded 46.5 wt% of methanol at a 48% methane conversion, at a maximum of 180°C. Per-FTPhPFe 3+ OH/Al 2 O 3 testing in propane hydroxylation by H 2 O 2 yielded 39.3 mol% of isopropanol. Per-FTPhPFe 3+ OH/Al 2 O 3 -catalyzed propylene oxidation by H 2 O 2 yielded 30 mol% of propylene oxide. PPFe 3+ OH/Al 2 O 3 -catalyzed propylene epoxidation yielded the following: the selectivity on the monooxygenase products is about 100%, the selectivity on propylene oxide - 59.2%, propylene conversion - 93.3%. The experimental research data revealed the fact that during the reaction of epoxidation per-FTPhPFe 3+ OH/Al 2 O 3 proved to be more stable under the influence of oxidizer and temperature than PPFe 3+ OH/Al 2 O 3 .  相似文献   
74.
The authors investigated the solubility of the gas components in the natural gas-condensate systems and its importance in gas-condensate reservoir development. Also, they discuss some fundamental aspects of preferable methods for recovering trapped retrograde condensate in the formation that is left after primary production. Based on the obtained results from the constant composition expansion test of seven different gas-condensate systems provided a greater understanding of the occurrences and interchanges between liquid and gas phases in the recombined reservoir fluids. The correlation between amount of the dissolved gas in the liquid phase, the volume of vaporized condensate in the gas phase and retrograde condensation pressure was investigated. Analysis of this data identified that increasing dissolved gas in the liquid phase, increases vaporized condensate even in the same thermobaric condition and decreases the retrograde condensation pressure of the gas-condensate systems. It was determined that the solubility of gas components in the fluid should be considered when projecting the gas-condensate reservoirs development. As, improving the solubility of gas components in the condensate decreases the system fog up and retrograde condensation pressures and improves stability of aerosol condition of gas-condensate fluid, it influences on the reservoir condensate bearing to be increased. Therefore, injected gas for gas cycling or revaporization of accumulated condensate from the core can be controlled for the purpose of increasing its solubility and condensate bearing capability.  相似文献   
75.
The photoelectrochemical properties of TiO2, CdS, and TiO2/CdS anodes have been studied. The results demonstrate that, under illumination, CdS anodes are subject to photocorrosion, and Cd2+ ions pass into solution. Corrosion-resistant films of TiO2 prevent CdS photocorrosion, and the CdS/TiO2 system exhibits good photosensitivity in the visible range.  相似文献   
76.
Electro-optical effects of planar nematic liquid crystal cells doped with dye and carbon nanotubes (CNTs) were investigated by utilizing the absorption property of the dye. Voltage-dependent transmittance and hysteresis measurements under applied ac and dc fields were presented. Cells doped with both Methyl Red and CNTs showed increased conductivity and capacitance, slower ac-rise switching time and dc-backflow on turn-off. The cells exhibited little hysteresis but those containing CNTs reduced residual dc by about 50%. First-order probe diffraction of permanent gratings revealed a correlation of ac-field-enhanced diffraction efficiency and Fréedericksz threshold voltage.  相似文献   
77.
This paper proposes a method for finding the efficiency of solar air heaters based on a comparison of their thermal and hydrodynamic characteristics with the thermal and hydrodynamic characteristics of flat plate-type solar air heaters. Calculations performed for different designs of air heaters have shown the great potential of this method to create efficient designs of solar air heaters.  相似文献   
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Various alkyl nitronitrates based on individual olefins and mixtures of propylene trimer and tetramer isomers have been derived. Hydroxyesters have been synthesized via the reaction of natural naphthenic acid with propylene oxide in different molar ratios, as have complexes of chromium, nickel, and cobalt salts of natural naphthenic acids with alkyl nitronitrates. The electric conductivity of 0.001% solutions of nitro compounds in diesel fuels has been examined. It has been found that the antistatic properties of the chromium and nickel salts prevail, with the greatest antistatic effect being displayed by the complexes of the chromium salt. Hydroxyesters in a 1: 1 molar ratio also exhibit a strong antistatic effect.  相似文献   
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