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131.
The adsorptive denitrogenation from fuels over three metal-organic frameworks(MIL-96(Al),MIL-53(Al)and MIL-101(Cr))was studied by batch adsorption experiments.Four nitrogen-containing compounds(NCCs)pyridine,pyrrole,quinoline and indole were used as model NCCs in fuels to study the adsorption mechanism.The physicochemical properties of the adsorbents were characterized by XRD,N2physical adsorption,FT-IR spectrum and Hammett indicator method.The metal-organic frameworks(MOFs),especially the MIL-101(Cr)containing Lewis acid sites as well as high specific surface area,can adsorb large quantities of NCCs from fuels.In addition,the adsorptive capacity over MIL-101(Cr)will be different for NCCs with different basicity.The stronger basicity of the NCC is,the more it can be absorbed over MIL-101(Cr).Furthermore,pore size and shape also affect the adsorption capacity for a given adsorbate,which can be proved by the adsorption over MIL-53(Al)and MIL-96(Al).The pseudo-second-order kinetic model and Langmuir equation can be used to describe kinetics and thermodynamics of the adsorption process,respectively.Finally,the regeneration of the used adsorbent has been conducted successfully by just washing it with ethanol. 相似文献
132.
A novel one-step protocol for the preparation of porous polyurea material (PPU) through precipitation polymerization of toluene diisocynate (TDI) is presented. The process is based on step polymerization of one singlemonomer, TDI, with water in water-acetonemixed solvent. PPU is obtained without need for any porogen or additives, and no any chemical modification on the outcome polymer is necessary. The morphology, pore size and size distribution of PPU are characterized by scanning electron microscope and BET nitrogen adsorption. Taking acid fuchsine (AF) and Congo Red as dye examples in wastewaters, their adsorption on, desorption from PPU and the reusability of PPU were tested. Experimental conditions for AF adsorption were optimized with regard to pH, adsorption time, AF concentration and amount of PPU. Results demonstrate that the as-prepared PPU is of high performance in dyes adsorption and recycled use. This work presents therefore a novel and attractive candidate for removal of anionic dyes from wastewaters. 相似文献
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Kong Ji-Zhou Ren Chong Jiang You-Xuan Zhou Fei Yu Chao Tang Wei-Ping Li Hui Ye Sheng-Yi Li Jun-Xiu 《Journal of Solid State Electrochemistry》2016,20(5):1435-1443
Journal of Solid State Electrochemistry - Li2TiO3 is used as a novel coating material to modify Li(Li0.2Mn0.51Ni0.19Co0.1)O2 electrode to enhance the electrochemical performance of the host... 相似文献
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Gas‐phase ion–molecule reactions for the identification of the sulfone functionality in protonated analytes in a linear quadrupole ion trap mass spectrometer 下载免费PDF全文
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Journal of Solid State Electrochemistry - Hydroxide precursor Ni0.5Co0.2Mn0.3(OH)2 was successfully prepared by co-precipitation using lactic acid as the environment-friendly chelating agent. And... 相似文献
139.
The dynamic characteristics of drilling shaft in deep hole drilling influenced by minimal quantity lubrication (MQL) is investigated. According to the features of the compressible fluid Reynolds equation in oil/air feature, a time-dependent mathematical model is established to describe the pressure distribution of cutting fluid with nonlinearity in MQL deep hole drilling. By introducing the differential transformation approach, the time-dependent pressure equation arising from cutting fluid is solved by the use of direct integral method. The influences of the rotational speed, the transverse displacement ratio, and radial clearance on the hydrodynamic pressure distribution of cutting fluid are obtained. The advantage of this method is to overcome much of the computational cost and has its rapid convergence rate. Furthermore, the nonlinear responses of drilling shaft influenced by MQL are analyzed, and the instability rotational speeds of drilling tool are discussed while the design parameters of drilling shaft system changing. 相似文献
140.
Motasem Y. D. Alazaiza Su Kong Ngien Mustafa M. Bob Samira A. Kamaruddin Wan Mohd Faizal Ishak 《Transport in Porous Media》2017,117(1):103-123
Double porosity is a substantial microstructure characteristic in a wide range of geomaterials. It is a natural phenomenon that can be found in many types of soil, and it can result from biological, chemical or mechanical damage. In this paper, the influence of macro-pores on dense non-aqueous phase liquid (DNAPL) migration in double-porosity medium was investigated using light transmission visualization technique. Three experiments were carried out in two-dimensional flow chambers filled with a double-porosity medium composed of a mixture of local sand and sintered kaolin clay spheres arranged in a periodic manner. In each experiment, a different volumetric fraction of macro-pores and micropores was used. Tetrachloroethylene (PCE) was used to simulate DNAPL, and it was dyed using Oil-Red-O for better visualization. A predetermined amount of PCE was injected into the flow chambers and this amount was re-calculated using image analysis. A very strong correlation was found between the PCE amount injected and the amount calculated from image analysis in each experiment. The experiment was repeated by filling the flow chamber with silica sand to represent single-porosity medium. The results show that the macro-pores have a considerable effect on the PCE migration in double-porosity soil as the PCE movement was the fastest in the third experiment which contained the largest macro-pores volume. The accuracy of the method was validated using statistical analysis. The results show a slight difference between the means of the three experiments, indicating that the method is viable for monitoring NAPL migration in double-porosity medium under different volumetric fractions of macro-pores and micropores. 相似文献