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101.
Paper like free-standing hybrid single-walled carbon nanotubes air electrodes for zinc–air batteries
Nutan Gupta Tingji Toh Mak Wai Fatt Subodh Mhaisalkar Madhavi Srinivasan 《Journal of Solid State Electrochemistry》2012,16(4):1585-1593
Flexible electrode architectures based on non-functionalized (P2) and functionalized (P3) single-walled carbon nanotubes (SWNTs)
were fabricated via a simple vacuum filtration process. A hybrid layer of various compositions of P2- and P3-SWNTs forms free-standing
membranes (~80 μm in thickness), and their electrochemical performance was evaluated as an air electrode AEP2/P3 in zinc–air batteries. Such bifunctionalized air electrodes showed uniform surface morphology with interconnected micron-sized
porous structure with high porosity (~70%). The N2 adsorption isotherms at 77 K are of type IV with BET-specific surface areas of AE(60/40) and AE(80/20) to be 130.54 and 158.76 m2 g−1, respectively, thus facilitates high active surface area for active oxygen reduction/evolution reactions. BJH pore size distribution
of AE(60/40) and AE(80/20) shows maximum pores with diameter <15 nm. The zigzag interlaying of the SWNTs imparts mechanical stability and flexibility
in zinc–air batteries. Zinc–air batteries with optimized compositions of P2- and P3-SWNTs in air electrode AE(60/40) had ionic conductivity ~1 × 10−2 S cm−1 and delivered higher discharge capacity ~300 mAh g−1 as compared to AE(80/20) composition. The unique properties of AE(P2/P3) studied in this work would enable flexible air electrode architectures in future metal–air batteries. 相似文献
102.
103.
Z. Liu Y.H. Zhang X.H. Zhou M.L. Liu W.J. Luo Q.Y. Pan Z.G. Gan T. Hayakawa M. Oshima Y. Toh T. Shizima Y. Hatsukawa A. Osa T. Ishii M. Sugawara 《The European Physical Journal A - Hadrons and Nuclei》2002,13(3):277-280
Excited states of 142Ce, populated in deep inelastic reactions of 82Se projectiles bombarding 139La target, have been studied up to medium spins using in-beam γ spectroscopy techniques. Three new levels have been identified
at 2625, 2995, 3834 keV, and assigned as 8+, 9(-) and 11(-), respectively. These new yrast states follow closely the level systematics of the even mass N = 84 isotones. Their strctures have been discussed with the help of empirical shell model calculations.
Received: 2 November 2001 / Accepted: 15 January 2002 相似文献
104.
A time delay and integration imaging technique is presented and applied to internal surface contour measurement. Using the proposed optical arrangement, inspection of profiles of objects which are mounted on the internal surface of a hollow cylinder can be carried out. Tests conducted on objects with diameters ranging from 40 to 214 mm show good agreement with results obtained from conventional profilometer. 相似文献
105.
106.
Briseno AL Han S Rauda IE Zhou F Toh CS Nemanick EJ Lewis NS 《Langmuir : the ACS journal of surfaces and colloids》2004,20(1):219-226
The use of nanosphere lithography to construct two-dimensional arrays of polystyrene (PS) particles coated with multilayered polyelectrolyte (PE) shells and truncated eggshell structures composed of PE thin layers is reported. The truncated eggshell PE structures were produced by extraction of the PS particle cores with toluene. The core-extraction process ruptures the apex of the PE coating and causes a slight expansion of the PE thin layers. Aniline hydrochloride was infiltrated into the PE shells and subsequently electropolymerized to yield an array of a composite containing polyaniline (PAni) and PE thin shells. Voltammetric, quartz crystal microbalance, and reflectance Fourier transform infrared spectroscopic measurements indicate that aniline monomers were confined within the thin PE shells and the electropolymerization occurred in the interior of the PE shell. The PE thickness governs the amount of infiltrated monomer and the ultimate loading of the PAni in the truncated eggshell structure. Surface-structure imaging by atomic force microscopy and scanning electron microscopy, carried out after each step of the fabrication process, shows the influence of the PE thickness on the organization and dimensions of the arrays. Thus, the PE thin shells composed of different layers can function as nanometer-sized vessels for the entrapment of charged species for further construction of composite materials and surface modifications. This approach affords a new avenue for the synthesis of new materials that combine the unique properties of conductive polymers and the controllability of template-directed surface reactions. 相似文献
107.
Mechanism of antimicrobial activity of CdTe quantum dots 总被引:1,自引:0,他引:1
Lu Z Li CM Bao H Qiao Y Toh Y Yang X 《Langmuir : the ACS journal of surfaces and colloids》2008,24(10):5445-5452
The antimicrobial activity and mechanism of CdTe quantum dots (QDs) against Escherichia coli were investigated in this report. Colony-forming capability assay and atomic force microscopy (AFM) images show that the QDs can effectively kill the bacteria in a concentration-dependent manner. Results of photoluminescence spectrophotometry, confocal microscopy, and antioxidative response tests indicate that the QDs bind with bacteria and impair the functions of a cell's antioxidative system, including down-regulations of antioxidative genes and decreases of antioxidative enzymes activities. The oxidative damage of protein and lipid is also observed with thiobarbituric reacting substances and protein carbonyl assays, respectively. On the basis of these results, it is proposed that the mechanism of the antimicrobial activity of CdTe QDs involves QDs-bacteria association and a reactive oxygen species-mediated pathway. Thus, CdTe QDs could have the potential to be formulated as a novel antimicrobial material with excellent optical properties. 相似文献
108.
Y. Toh M. Oshima M. Koizumi A. Kimura Y. Hatsukawa 《Journal of Radioanalytical and Nuclear Chemistry》2008,276(1):217-220
From extraction experiments and γ-activity measurements, the exchange extraction constants corresponding to the general equilibrium M+(aq)+NaL+(nb)⇔ML+(nb)+Na+(aq) taking place in the two-phase water-nitrobenzene system [M+=Li+, K+, Rb+, Cs+; L = p-tert-butylcalix[4]arene-tetrakis (N, N-dimethylthioacetamide); aq = aqueous phase, nb = nitrobenzene phase] were evaluated. Furthermore,
the stability constants of the ML+ complexes in water saturated nitrobenzene were calculated; they were found to increase in the cation order Cs+<Rb+<K+<Li+<Na+. 相似文献
109.
Y. Toh M. Oshima A. Kimura M. Koizumi K. Furutaka Y. Hatsukawa J. Goto 《Journal of Radioanalytical and Nuclear Chemistry》2008,278(3):685-689
Low-energy photons produced by the Compton scattering from hydrogen increase the background in the lower-energy region of
the gamma-ray spectrum. This results in an increase in the detection limit for trace elements. In multiple photon detection
prompt gamma-ray analysis (MPGA), only those elements that simultaneously emit two or more prompt gamma-rays, which have cascade
relation and are emitted within a short interval, can be measured. Therefore, the influence of hydrogen can be reduced. In
this study, standard polymer and food samples are measured. The hydrogen background is reduced in MPGA. 相似文献
110.
The Ramanujan Journal - In this paper we present a new formula for the number of unrestricted partitions of n. We do this by introducing a correspondence between the number of unrestrited... 相似文献