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61.
Metal nanocluster composite glass prepared by 200 keV Ag ions' implantation into silica with dose of 2 × 1017 ions/cm2 has been studied. The formation of sandwiched nanocluster-nanovoid-nanocluster structures has been evidenced by in situ transmission electron microscopy experiment (TEM). Fast nonlinear optical refraction and nonlinear optical absorption coefficients were measured at 532 nm and 1064 nm of wavelength by the Z-scan technique. The third-order nonlinear susceptibility χ(3) of this kind of sample was determined to be 4.0 × 10−8 esu at 532 nm and 9.0 × 10−8 esu at 1064 nm, respectively. 相似文献
62.
Platinum has been widely applied in catalytic industry and the recovery of noble metals from industrial wastes becomes an economic issue. The laboratory studies of platinum(IV) microquantities removal from 1M aluminium, copper, iron, nickel and zinc chloride solutions in 0.1M hydrochloric acid solutions on the anion exchanger Duolite S 37 of the functional secondary and tertiary amine groups were carried out. For this anion exchanger the fraction extracted values (%E, Pt(IV)) as well as the sorption isotherms were determined depending on the kind of aqueous phase and phase contact time. Moreover, the bed and weight distribution coefficients as well as working and total ion-exchange capacities were calculated from the platinum(IV) breakthrough curves. Kinetic parameters were determined. 相似文献
63.
Jian Xu Fred J. Sigworth David A. LaVan 《Advanced materials (Deerfield Beach, Fla.)》2010,22(1):120-127
Synthetic protocells provide a new means to probe, mimic and deconstruct cell behavior; they are a powerful tool to quantify cell behavior and a useful platform to explore nanomedicine. Protocells are not simple particles; they mimic cell design and typically consist of a stabilized lipid bilayer with membrane proteins. With a finite number of well characterized components, protocells can be designed to maximize useful outputs. Energy conversion in cells is an intriguing output; many natural cells convert transmembrane ion gradients into electricity by membrane‐protein regulated ion transport. Here, a synthetic cell system comprising two droplets separated by a lipid bilayer is described that functions as a biological battery. The factors that affect its electrogenic performance are explained and predicted by coupling equations of the electrodes, transport proteins and membrane behavior. We show that the output of such biological batteries can reach an energy density of 6.9 × 106 J · m?3, which is ～5% of the volumetric energy density of a lead‐acid battery. The configuration with maximum power density has an energy conversion efficiency of 10%. 相似文献
64.
In this paper the effects of a strong magnetic field on plasma immersion ion implantation (PHI) of dielectric substrates were investigated. A plasma fluid model and finite difference schemes were used to simulate a one-dimensional system of plasma immersion ion implantation. The effect of secondary electron emission from the electrode on PHI was also taken into consideration. It was found that the magnitude and direction of the magnetic field have slight effects on sheath thickness but have considerable effects on current densities in the y and z directions which are perpendicular to the direction of the electric field (the x direction). The simulations showed that the current densities in the y and z directions increased significantly with increasing magnitude of the magnetic field at a given fixed angle, the reason being attributed to the rotational force exerted on the ions by the magnetic field. With a fixed magnetic field, increasing the angle of the magnetic field, θ, with respect to the electric field produced a continuous increase in current density in the y direction from zero to its maximum at θ = 90° but the current density in the z direction could be described as saddle-shaped being zero at both ends. 相似文献
65.
66.
A. Meldrum R. F. Jr. Haglund L. A. Boatner C. W. White 《Advanced materials (Deerfield Beach, Fla.)》2001,13(19):1431-1444
Ion implantation has become a versatile and powerful technique for synthesizing nanometer‐scale clusters and crystals embedded in the near‐surface region of a variety of hosts in order to create nanocomposite materials with often unique optical, magnetic, and other properties. Here we review some of the principal features of this nanophase materials synthesis technique as well as the materials properties that are exhibited by nanocomposites created by using ion beams. Outstanding difficulties and future research directions are also discussed. 相似文献
67.
M. Miyakawa K. Hayashi M. Hirano Y. Toda T. Kamiya H. Hosono 《Advanced materials (Deerfield Beach, Fla.)》2003,15(13):1100-1103
68.
Y. Ono M. Inomoto Y. Ueda T. Matsuyama 《Science and Technology of Advanced Materials》2001,2(3-4):473-482
Magnetic reconnection of two toroidal plasmas with the third field component BX parallel to the X-lines revealed a clear dependence of sheet-current resistivity and ion heating energy on the sheet-width normalized by the ion gyroradius. Initially, the effective resistivity of sheet-current stayed constant, but it increased significantly when the sheet was compressed shorter than the ion-gyroradius. The anomalous current-sheet dissipation was followed by large increase in ion outflow velocity and ion temperature. This anomalous effect caused both the reconnection speed and the ion heating energy to increase with external compression force and inversely with the BX component. These properties of reconnection lead us to a new controlled plasma heating for various fusion plasmas and other industrial plasmas. 相似文献
69.
Rykaczewski K Hildreth OJ Wong CP Fedorov AG Scott JH 《Advanced materials (Deerfield Beach, Fla.)》2011,23(5):659-663
A process that allows control over the 3D motion of catalyst nanostructures during metal-assisted chemical etching by their local pinning prior to etching is demonstrated. The pinning material acts as a fulcrum for rotation of the catalyst structures resulting in etching of silicon features with rotational geometry. 相似文献
70.
提出了把Kielland模型用于有机阴离子交换树脂研究二元酸根交换平衡的依据,用RHCO_3-CO_3~(2-)体系证明了Kielland方程可推广到Ⅰ-Ⅱ价交换平衡。用~(14)C标记技术求出了μ=0.30、t=25℃时混合交换平衡常数K_B~A=2.41,特征常数C=0.24。和RHSO_4-SO_4~(2-)交换体系对比,明确了选择性次序为:HSO_4~->SO_4~(2-)>>CO_3~(2-)>HCO_3~-,还对二元酸根在树脂内的转化作了讨论。 相似文献