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51.
52.
利用微波辅助有机溶胶法成功制备了Pd3Ru/C纳米电催化剂。相比传统的高压有机溶胶法,该法大大降低了有机溶剂的使用量并缩减了反应时间,是一种环境友好和资源节约的新型方法。采用XRD,TEM,XPS和电化学测试等手段对其结构和电化学性能进行了表征和评价。XRD和TEM结果表明微波辅助制备的Pd3Ru/C催化剂其粒径只有约3.0 nm,分散性也较Pd/C得到显著改善;XPS谱图证实催化剂活性组分Pd和Ru的原子比约为3.13∶1,Pd和Ru两种元素间发生了相互作用。与同条件制备的Pd/C催化剂相比,Pd3Ru/C催化剂在电极上发生甲酸氧化反应的主要峰电位负移了约100 mV,峰电流密度增大了2/3左右,其甲酸电氧化活性得到明显提高。 相似文献
53.
Wonyoung Lee Hee Joon Jung Min Hwan Lee Young‐Beom Kim Joong Sun Park Robert Sinclair Fritz B. Prinz 《Advanced functional materials》2012,22(5):965-971
The role of grain boundaries on oxygen surface exchange in an oxide ion conductor is reported. Atomic‐scale characterization of the microstructure and chemical composition near the grain boundaries of gadolinia‐doped ceria (GDC) thin films show the segregation of dopants and oxygen vacancies along the grain boundaries using the energy dispersive spectroscopy in scanning transmission electron microscopy (STEM‐EDS). Kelvin probe microscopy is employed to verify the charge distribution near grain boundaries and shows that the grain boundary is positively charged, indicating a high concentration of oxygen vacancies. AC impedance spectroscopy on polycrystalline GDC membranes with thin interfacial layers with different grain boundary densities at the cathodes demonstrated that the cells with higher grain boundary density result in lower electrode impedance and higher exchange current density. These experimental evidences clearly show that grain boundaries on the surface provide preferential reaction sites for facilitated oxygen incorporation into the GDC electrolyte. 相似文献
54.
Constantinos Tsanaktsidis Spiros Bousios Konstantinos Spinthiropoulos George Tzilantonis Apostolos Scaltsoyiannes 《Petroleum Science and Technology》2018,36(17):1332-1339
One of the important stages in the preparation of fuel for the smooth progress of combustion is to remove humidity from it. Natural resin, a natural product from Pinus nigra and Pinus halepensis were used in order to remove water residues from petroleum fuels. The mass of resin (P. nigra and P. halepensis) was mixed with diesel fuel and the humidity eliminated, 38% and 69% of diesel fuel also. The proposed method can be used in a simple fuel cleaning process using a metal mesh vessel consisted of the natural resin of P. nigra sample. 相似文献
55.
Samira Shirvani 《Petroleum Science and Technology》2018,36(11):750-755
This paper explores the effect of incorporation of a nanoporous silica as diluent for a USY catalyst in the presence or absence of steam, as a cost-effective hydrogen donor and regenerative agent, in the fuel oil upgrading. We found that the incorporation of inert silica in the catalyst particles in the presence of steam could produce more than 40 wt% of olefinic products, mainly propylene, in the cracked products. With the elimination of steam, the olefins yield became less than a half (about 17 wt%) and the reaction tended towards higher liquid yields (74.8 wt%) including gasoline and diesel fuel. 相似文献
56.
Blending 10?vol% of ethanol into hydrocarbon base gasoline (HBG) increases significantly the vapour pressure of the blend (E10), and exhibits near-azeotrope behaviour that severely affects the shape of E10 distillation curve. The distillation curves of HBG and E10 fuel blend, were constructed using ASTM D86 distillation data, and the areas under each distillation curve, were calculated through the numerical trapezoid rule (NTR) and calculus definite integration (CDI) methods. Consequently, the area due to azeotrope formation (ADAF), was estimated. In this paper, we present the impact of small concentration of nonionic surfactant on the area under distillation curve (AUDC) of E10 fuel blend and the area due to azeotrope formation (ADAF). Also, the influences of the added surfactant on the volatility criteria of the investigated E10 fuel blend were discussed. 相似文献
57.
58.
介绍了中国石化塔河炼化0.3 Mt/a 喷气燃料加氢装置以常一线为原料,间歇生产满足GB 6537—2006的3号喷气燃料和满足国Ⅳ或国Ⅴ排放标准的柴油产品的生产经验。柴油产品全面升级后,通过简单的工艺调整,可以实现生产喷气燃料及生产满足国Ⅴ排放标准柴油两种加工方案的切换。生产3号喷气燃料,生产满足国Ⅳ排放标准柴油,生产满足国Ⅴ排放标准柴油这三种加工方案下,反应器入口温度依次相差约20℃。通过比较不同加工方案的差异性及催化剂的失活速率,提出今后喷气燃料加氢装置催化剂长周期运行的建议。 相似文献
59.
中海油惠州石化有限公司3.6 Mt/a加氢裂化装置柴油回炼增产喷气燃料和石脑油的工业应用结果表明,在不改变装置结构和催化剂的基础上,回炼少量柴油(4%),转化率可达到75%,喷气燃料、石脑油目标产品收率提高3.29百分点,喷气燃料烟点略有提高,柴油十六烷值提高3.9个单位,产品质量合格,装置能耗略有增加,从856.21 MJ/t增加到859.72 MJ/t。 相似文献
60.
The power generation demand is increasing day-by-day throughout the world, therefore, the use of hybrid systems becomes a significant solution. The hybrid renewable energy system (HRES) is used for delivering power in various regions in order to overcome intermittence of wind and solar resources. Because of increasing environmental problems, for example, greenhouse gas emission and energy cost have interested novel research into substitute methods in favour of electrical power generation. Maximum Power Point Tracking (MPPT) control method is a vast deal of novel research used for enhancing the efficiency of HRES. The authors have revealed that the hybrid techniques i.e. Global MPPT, fuzzy-neuro systems, Adaptive Neuro-Fuzzy Inference System (ANFIS), Perturbed and Observe (P&O) + Adaptive Neural Network (ANN) etc. can provide best results as compared to other MPPT control methods. This paper offering a state of art review of MPPT control techniques for HRES. 相似文献