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51.
Chiranjeeva Rao Seela B. Ravisankar 《Energy Sources, Part A: Recovery, Utilization, and Environmental Effects》2018,40(21):2564-2571
This work investigates the suspension duration of the nanosized multiwalled carbon nanotubes (MWCNT) and aluminum oxide (Al2O3) in B20, B50 and B70 blends of Jatropha Methyl ester. The MWCNT and aluminum oxide (Al2O3) are added to the fuel blends in the proportions of 50 and 100 pmm separately by ultra sonication. The prepared fuel samples are characterized, and turbidity analysis was done to find the stability rate of nano-additives. The outcomes reveal the maximum stability rate for MWCNT and Al2O3 as 83.3% and 87.03%, respectively, with 50ppm in B20 over a period of eighteen days. A considerable drop in suspension was observed with the 100 ppm MWCNT and Al2O3 biodiesel blends. 相似文献
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羟乙基乙二胺(AEE)水溶液的CO2循环吸收量高(1.2molCO2/molAEE),吸收速度快,稳定性好,但解吸速度慢、解吸量少(0.8mol CO2/mol AEE)是限制该技术广泛应用的主要原因。本文通过向AEE水溶液中添加质量分数为0.05%~0.20%的改性氧化钛(TiO2-MWCNT和TiO2-OH)强化AEE的解吸能力。CO2循环吸收(40℃)-解吸(120℃)实验结果表明改性氧化钛的添加比氧化钛强化CO2解吸效果更好,强化顺序为TiO2-MWCNT>TiO2-OH;其对应的最大解吸速率分别为0.093L/min(质量分数0.15%)和0.083L/min(质量分数0.20%),相对于AEE水溶液,分别提高了32.9%和18.6%;其对应的最大解吸量分别为0.92molCO2/molAEE(质量分数0.15%)和0.88molCO2/molAEE(质量分数0.20%),分别提高了12.2%和9.7%;其对应的CO2循环吸收量分别是0.95molCO2/molAEE(质量分数0.15%)和0.89molCO2/molAEE(质量分数0.15%),分别提高了18.75%和11.25%;5次循环吸收解吸实验结果表明改性氧化钛强化CO2解吸效果稳定,具有较强的化学稳定性。对反应后的改性氧化钛进行XRD、BET、FTIR和SEM表征,结果表明改性氧化钛具有较强的结构稳定性。TiO2-MWCNT和TiO2-OH在促进有机胺溶液解吸CO2方面具有一定的工业应用潜力。 相似文献
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Oxygen reduction reaction(ORR) plays a critical role in many energy conversion and storage processes.Therein, a comparative study of the electrocatalytic activity for ORR in 0.1 mol/L KOH solution was conducted using layered perovskite-like LaSr_3 Fe_3 O_(10) and LaSr3 Fe_3 O_(10)-graphene oxide(GO) composite as electrodes. Linear sweep voltammetry(LSV) results show that the LaSr3 Fe_3 O_(10)-GO hybrid exhibits higher current density, a more positive onset potential(-0.15 V vs. Hg/HgO) in comparison with LaSr_3 Fe_3 O_(10).The value of the overall transferred electrons for both catalysts implies a dominant two electron process for ORR. Both catalysts under alkalic conditions exhibit a two-step Tafel slope, suggesting a change in the reaction mechanism for ORR. The composite electrode exhibits a higher ORR current density, but inferior durability performances in relative to the LaSr_3 Fe_3 O_(10) electrode. 相似文献
57.
Multiple degrees‐of‐freedom (multi‐DOF) cell orientation control is a vital important technique involved in single cell surgery applications. Currently, few studies have been performed toward automation of multi‐DOF cell orientation control using robotically controlled optical tweezers. In this paper, a robust control framework is developed to perform multi‐DOF cell rotational control with consideration of model uncertainties and external disturbances. Both simulation and experimental studies are presented to illustrate the performance of the proposed control strategy. The main contributions of this work lie in that this is the first time to develop a unified framework to achieve multi‐DOF cell orientation control without the need for accurate dynamic model parameters and/or any knowledge about uncertainty characteristic, which greatly enhances the robustness of the overall system. 相似文献
58.
Ondrej Hanzel Meinam Annebushan Singh Deepak Marla Richard Sedlák Pavol Šajgalík 《Journal of the European Ceramic Society》2019,39(8):2626-2633
SiC based composites filled with graphene nano-platelets (GNPs) or graphene oxide (GO) prepared by rapid hot-pressing exhibit sufficient electrical conductivity for their machinability by wire electro-discharge machining (WEDM). Composites microstructure anisotropy caused by graphene alignment as a consequence of rapid hot pressing was confirmed by measuring of electrical conductivity and thermal diffusivity. Electrical conductivity increased significantly with increased weight fraction of graphene in both measured directions. Highest value of 2031 S/m was obtained for composites with 15 wt. % of GNPs in parallel direction and only 1246 S/m in perpendicular direction to aligned GNPs. Thermal diffusivity is 63.3 mm2/s in parallel and only 23.3 mm2/s in perpendicular direction. The increase of the electrical conductivity has resulted in successful WEDM. The MRR was almost doubled when the filler concentration increased from 5 wt. % GNPs/GO to 15 wt. % GNPs. At the same time, the surface roughness decreased. 相似文献
59.
A two‐step synthetic procedure is designed for preparing new flame‐retardant methacrylic monomers containing 9,10‐dihydro‐9‐oxa‐10‐phosphaphenanthrene‐10‐oxide (DOPO) as a substituent side group. DOPO and methacrylate moieties are linked by linear aliphatic hydrocarbon spacers (3 to 11 carbon atoms). Copolymerization with methyl methacrylate is carried out leading to copolymers containing between 2 and 10 wt% phosphorus. All homo‐ and copolymers exhibit a unique glass transition temperature (Tg ). A new group contribution for DOPO‐based substituent is extracted that leads to reasonable estimations of Tg s of other published polymers. The Fox equation provides a good estimation of Tg s for most copolymers and for physical blends of poly(methyl methacrylate) (PMMA) and DOPO. When using monomers having three and four carbon atoms in the hydrocarbon spacer, the Tg of copolymers remains close to that of PMMA over a wide range of composition. 相似文献
60.