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971.
Akhil Garg Liu Yun Su Shaosen Ankit Goyal Xiaodong Niu Liang Gao Yogesh Bhalerao Biranchi Panda 《国际能源研究杂志》2019,43(9):4390-4402
The present research proposes a combined framework that evaluates remaining capacity, material behavior, ions concentration of remaining metals, and current rate of chemical reactions of spent Li‐ion batteries accurately. Voltage, temperature, internal resistance, and capacity were studied during charging and discharging cycles. Genetic programming was applied on the obtained data to develop a model to predict remaining capacity. The results of experimental work and those estimated from model were found to be correlated, confirming the validation of model. Materials structure and electrochemical behavior of electrodes during cycles were studied by cyclic voltammetry, scanning electron microscopy, and energy dispersion spectrum. 相似文献
972.
Lina Tao Ting Zhang Panpan Wang Mengzhen Ding Lijie Liu Ningping Tao Xichang Wang Jian Zhong 《International Journal of Food Science & Technology》2021,56(10):5150-5159
Multicore millimetre-sized fish oil-loaded alginate capsules were developed using a combined monoaxial dispersion electrospraying–ionotropic gelation technique and their stability was explored. By adjusting the preparation parameters, the capsule shapes could be irregular, spherical with a short-tail, spherical, fusiform, and fusiform with a long-tail. The continuous phase of the millimetre-sized capsules consisted of hydrophilic alginate calcium and water. Moreover, the water content increased from 17% to 69% with increased alginate concentration (2.5–30 mg mL−1). The capsules prepared with alginate concentration of 10 mg mL−1 or 20 mg mL−1 show a similar loading ratio (about 5–8%) of fish oil during storage. Headspace solid-phase microextraction–gas chromatography mass spectroscopy (HS-SPME-GC-MS) results confirmed the capsules masked the fishy odour of fish oil. Moreover, fish oil slowly migrated from the inside to the outside of the capsules. This work presented a simple method to prepare multicore millimetre-sized capsules with controlled shapes and a basic understanding of the effect of encapsulation using alginate to mask the fish oil odour. 相似文献
973.
《International Journal of Hydrogen Energy》2020,45(57):32825-32833
In high-temperature polymer electrolyte membrane fuel cells (HT-PEMFCs), it is important that the structure of the electrode catalyst layer is formed uniformly. To achieve this, the binder must be well dispersed; however, polytetrafluoroethylene (PTFE), which is commonly employed in the preparation of HT-PEMFCs, is difficult to disperse during electrode manufacture due to its high hydrophobicity. In this study, we fabricate electrodes containing a surfactant to improve the dispersion of the PTFE binder and to enhance reproducibility during electrode manufacture. The electrodes are commonly prepared via a bar coating method, which is known to exhibit poor dispersion due to the small amounts of solvent employed compared to the spraying method. We then compare the properties of the obtained electrodes prepared in the presence and absence of the surfactant through physical and electrochemical characterization. It is found that the electrode containing the surfactant is structurally superior, and its single cell performance is significantly higher (i.e., 0.65 V at 0.2 Am cm−2). The single cells are suitable for operation at 150 °C using H2/air at atmospheric pressure and a total platinum loading of 2.0 mg cm−2. 相似文献
974.
Tomas Plachy Milan Masar Miroslav Mrlik Michal Machovsky Zuzana Machovska Erika Kutalkova Ivo Kuritka 《Advanced Powder Technology》2019,30(4):714-723
Investigation of pristine g-C3N4 and copper ions doped g-C3N4 as dispersed phases in silicone-oil based electrorheological (ER) fluids is reported for the first time. Pristine g-C3N4 was prepared via standard thermal polycondensation of urea. Introduction of Cu ions into g-C3N4 polymeric network was performed by treatment of pristine powder by a solution containing tetraammoniumdiaquacopper(II) complex ions followed by annealing. The structure and properties of products were revealed with the aid of XRD, FTIR, UV–Vis and XPS, and complemented by SEM investigation of morphology, pycnometry, BET analysis, and conductivity measurements. The response of prepared ER fluids to an external electric field was examined by rheometry and the effects visualized with optical microscopy. While ER fluids based on g-C3N4 exhibited negative ER effect (decrease in viscosity when the field is switched-on), ER fluids based on a g-C3N4/Cu-doped analogue exhibited positive ER effect. Dielectric spectroscopy using Havriliak-Negami model revealed that introduction of the dopant almost doubled the dielectric relaxation strength while the relaxation time was halved. The ability of g-C3N4/Cu as a candidate for further studies necessary to increase the ER effect was demonstrated. Thereto, described modification of g-C3N4 by copper ions shall be applicable also for other metals forming ammonia complexes. 相似文献
975.
Henry C. W. Chu Stephen Garoff Robert D. Tilton Aditya S. Khair 《American Institute of Chemical Engineers》2020,66(2):e16831
A multiple-scale perturbation is conducted to derive an averaged equation for predicting the longtime solute transport in an eccentric annulus in which the uniaxial flow may oscillate periodically in time. A proof for the positiveness of the dispersivity is presented, implying that over a cycle of oscillation a solute cloud always broadens. For a steady flow driven by a fixed pressure gradient, increasing the eccentricity and annulus size gives rise to stronger dispersion. This relationship holds when the flow becomes unsteady. In the limit of slow oscillation, dispersion due to an oscillatory flow asymptotes to one-half of that by a steady flow. Increasing the oscillation frequency leads to a two-step decay of the dispersivity. The maximum dispersion in an oscillatory flow can be achieved in the limit of slow oscillation and large eccentricity, where dispersion can be O(103) times larger than that in an otherwise concentric annulus. 相似文献
976.
Jing Zhang Qiming Wang Zhonglin Zhu Hongliang Qian Feng Jiang Zhixiang Wang Wei Liu Dechun Huang 《化学工程与技术》2019,42(2):388-396
The antineoplastic gefitinib has a low aqueous solubility, leading to poor absorption rates. To overcome this problem, microparticles (MP) were prepared using solution‐enhanced dispersion by supercritical fluids (SEDS) with supercritical CO2 and the cosolvents dichloromethane and ethanol. The results showed that the use of SEDS resulted in the formation of smaller particles and rendered the usually heterogeneous crystals of the crude drug pure and uniform. Furthermore, the reduction in the MP size increased the dissolution rate of gefitinib, and in vitro cytotoxicity assays indicated that the MP inhibited the proliferation of A549 cells to a larger extent than did the crude drug. Given the beneficial properties of the MP, SEDS could potentially be used to micronize drugs for therapeutic applications. 相似文献
977.
利用力学性能测试、光学显微镜、扫描电镜、透射电镜和能谱分析技术等手段研究了均匀化过程中AlMnSi弥散颗粒的析出尺寸对6061铝合金再结晶行为的影响。结果表明:AlMnSi弥散颗粒在均匀化过程中沿着铝基体[001]晶带轴析出长大,晶体结构为体心立方结构。随着均匀化温度的升高,弥散颗粒的析出尺寸逐渐增大,当AlMnSi弥散颗粒平均尺寸由0.07 μm增长到0.42 μm,最大尺寸由0.21 μm增大到1.12 μm时,力学性能则是先升高后降低。6061铝合金T6态组织仍为变形组织;AlMnSi弥散颗粒尺寸增大到1.12 μm,6061合金T6态组织中出现粗大再结晶,力学性能急剧降低。 相似文献
978.
Yanhong Quan Ning Zhang Zhilei Zhang Yahong Han Jinxian Zhao Jun Ren 《International Journal of Hydrogen Energy》2021,46(27):14395-14406
A series of Ni/ZrO2 catalysts was prepared by the impregnation method with modification of the morphology of ZrO2 support as well as the impregnation procedure and tested for CO2 methanation. The catalysts supported on the ZrO2 nanosheets displayed superior catalytic performance as compared with that on ZrO2 nanoparticles, which could be mainly attributed to the abundant oxygen vacancies promoting the adsorption and dissociation of CO2 molecules as well as the high dispersion of Ni species. With the introduction of ethylenediamine (En) in the impregnation procedure, the resulting Ni-15En/ZrO2-1.5 catalyst showed the optimal activity with CO2 conversion of 86% significantly higher than Ni/ZrO2-0 of 44% and Ni/ZrO2-1.5 of 79% at 0.5 MPa and 300 °C. The excellent performance was attributed to increased moderately basic sites for CO2 adsorption in ZrO2 nanosheets, as well as the enhanced dispersion of nickel caused by the complexation of Ni ions with En, which inhibited the aggregation of nickel particles in the subsequent thermal treatments. In conclusion, the synergistic effects of the morphology of ZrO2 nanosheets as well as the chelating behavior of En contributed to the enhanced performance of Ni-15En/ZrO2-1.5 in the CO2 methanation reaction. The strategy shows good prospects for controlling the size of active metals, especially those that were dispersed on the surface of the two-dimensional (2D) metal oxide materials. 相似文献
979.
《International Journal of Hydrogen Energy》2022,47(11):7150-7167
The catalytic partial oxidation (CPO) of methane and iso-octane on Rh-coated monoliths is studied in an adiabatic reactor where axial temperature and concentration profiles are collected by a spatially resolved sampling technique. In CH4-CPO, the Rh/MgAl2O4 outperforms the Rh/α-Al2O3 formulation, due to a significant improvement of Rh dispersion. In iso-octane CPO, the beneficial effect of the improved Rh surface is less important due to the intrinsic lower sensitivity of the system. However, a non-negligible impact of Rh dispersion on the extent of hydrocarbon side-products is observed. This factor, together with the lower acidity of the spinel support, contributes to limit the C build-up. Reactor model and kinetic schemes allow to rationalize the measurements and explore the more general effect of Rh specific surface on the key performance indicators of the CPO reformer, that is syngas productivity and hot-spot temperature. Gas-solid diffusion rate makes such indicators strictly fuel-specific. 相似文献
980.