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61.
Baibai Liu Xinjuan Liu Lei Li Jianwei Li Can Li Yinyan Gong Lengyuan Niu Xinsheng Zhao Chang Q. Sun 《催化学报》2018,39(12):1901-1909
Development of efficient heterostructured photocatalysts that respond to visible light remains a considerable challenge. We herein show the synthesis of ZnIn2S4/carbon quantum dot hybrid photocatalysts with flowerlike microspheres via a facile solvothermal method. The ZnIn2S4/carbon quantum dot flowerlike microspheres display enhanced photocatalytic and photoelectrochemical activity compared with that of pure ZnIn2S4. With a content of only 0.5 wt % carbon quantum dots, 93% of Cr(VI) is reduced under visible-light irradiation at 40 min. As a co-catalyst, the carbon quantum dots improve the light absorption and lengthen the lifetime of charge carriers, consequently enhancing the photocatalytic and photoelectrochemical activity. 相似文献
62.
Polystyrene Sulfonate Threaded through a Metal–Organic Framework Membrane for Fast and Selective Lithium‐Ion Separation
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Dr. Yi Guo Dr. Yulong Ying Dr. Yiyin Mao Prof. Xinsheng Peng Prof. Banglin Chen 《Angewandte Chemie (International ed. in English)》2016,55(48):15120-15124
Extraction of lithium ions from salt‐lake brines is very important to produce lithium compounds. Herein, we report a new approach to construct polystyrene sulfonate (PSS) threaded HKUST‐1 metal–organic framework (MOF) membranes through an in situ confinement conversion process. The resulting membrane PSS@HKUST‐1‐6.7, with unique anchored three‐dimensional sulfonate networks, shows a very high Li+ conductivity of 5.53×10?4 S cm?1 at 25 °C, 1.89×10?3 S cm?1 at 70 °C, and Li+ flux of 6.75 mol m?2 h?1, which are five orders higher than that of the pristine HKUST‐1 membrane. Attributed to the different size sieving effects and the affinity differences of the Li+, Na+, K+, and Mg2+ ions to the sulfonate groups, the PSS@HKUST‐1‐6.7 membrane exhibits ideal selectivities of 78, 99, and 10296 for Li+/Na+, Li+/K+, Li+/Mg2+ and real binary ion selectivities of 35, 67, and 1815, respectively, the highest ever reported among ionic conductors and Li+ extraction membranes. 相似文献
63.
Global stability of a discrete virus dynamics model with Holling type‐II infection function
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In this paper, we propose a discrete virus dynamics model with Holling type‐II infection function. By constructing Lyapunov function, we prove that if , then the infection‐free equilibrium is globally asymptotically stable; whereas if , then sufficient conditions are established for global stability of the infection equilibrium. Our results generalize some known results studied by other researchers. Copyright © 2015 John Wiley & Sons, Ltd. 相似文献
64.
Peng X Jin J Ericsson EM Ichinose I 《Journal of the American Chemical Society》2007,129(27):8625-8633
A simple and general method for the preparation of ultrathin, large-area, free-standing films of nanofibrous composite materials was developed. First, positively charged cadmium hydroxide nanostrands of 1.9 nm in diameter and micrometers in length were prepared by mixing dilute aqueous solutions of cadmium chloride and aminoethanol. Negatively charged dye molecules, proteins, nanoparticles, and water-soluble fullerene or carbon nanotubes were mixed with the nanostrands to give a well-dispersed solution of the corresponding nanofibrous composites. After filtration of the dispersions with a polycarbonate membrane filter, uniform films with a thickness of a few tens to hundreds of nanometers and a diameter of a few centimeters were obtained. The films were readily peeled off from the membrane filter by immersion in ethanol. The resultant free-standing films could be further transferred to other substrates, such as quartz plate, gold electrode, and porous alumina membrane, and were characterized by scanning and transmission electron microscopies. We provide herein various nanofibrous free-standing films with optical, biological, metallic, and magnetic properties. 相似文献
65.
Pumera M Smíd B Peng X Golberg D Tang J Ichinose I 《Chemistry (Weinheim an der Bergstrasse, Germany)》2007,13(27):7644-7649
A novel protocol for precisely coating individual multiwall carbon nanotubes (MWCNTs) with an ultrathin layer of polypyrrole was developed. The nanocoated MWCNTs were successfully prepared by in situ chemical deposition of polypyrrole in an aqueous suspension of MWCNTs. The coating layer was very uniform and the thickness of the layer was determined by controlling the monomer concentration used, which gave nanometer precision. The products were characterized by transmission electron microscopy, scanning electron microscopy, Raman spectroscopy, X-ray photoelectron spectroscopy, electron energy loss spectroscopy, and conductivity and current-voltage measurements. The ultrathin polypyrrole layer could electrically insulate individual MWCNTs. 相似文献
66.
67.
用伏安法测绘二极管伏安特性的研究 总被引:2,自引:0,他引:2
本提出用伏安法测绘二极管伏安特性曲线的一种电路新接法,用该接法测量时,不需修正即可完全消除电表内阻的影响。 相似文献
68.
The aluminophosphate molecular sieve VPI-5 has received much attention as a new structure containing one-dimensional circular pores circumscribed by 18 tetrahedral atoms. The AlPO_4-8 is another new type of structure which was found to contain 1 4-ring open pores. Recently, we have successfully synthesized the molecular sieves of VPI-5 and AlPO_4-8, and found that the mixture of VPI-5 and AlPO_4-8 was easily formed under similar conditions, and VPI-5 can be converted to AlPO_4-8 by dehydration via heating. It is suggested that there exists relationship between the structures of VPI-5 and A1PO_4-8. Therefore, the study on the transition and relationship between VPI-5 and A1PO_4-8 is very important for designing and preparing new molecular sieves with new structures. 相似文献
69.
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