Position-selective growth of vertically aligned carbon nanotubes for application of electronic-measuring nanoprobes

Position-selective growth of carbon nanotubes (CNTs) and vertically aligned CNTs (VACNTs) on patterned metal electrodes have been prepared by thermal chemical vapor deposition (TCVD) and DC plasma enhanced chemical vapor deposition (PECVD). We propose newly a position-controlling method of CNTs by controlling not only a position of Ni as catalysts but also the morphology of Mo as underlayers for the catalysts. The position-selective growth of CNTs was achieved at the edges of the patterned metal by TCVD. The morphologies of the Mo underlayer at the selected area were rough and porous. No CNTs grew on smooth Mo surfaces. The minimum width of selectively grown CNTs, ca. 2.6 μm, was approximately one-eightieth of the patterned metal, 200 μm. VACNTs were synthesized by a PECVD method, however, the VACNTs grew up all over the patterned metal. The Ni catalysts formed into fine particles on rough surfaces of the Mo underlayer. Then the selective growth was achieved by Ni fine particles formed only at the edges of the metal pattern. The results of PECVD suggest that the plasma promoted the Ni catalysts to become fine particles on smooth surfaces of Mo. Conclusively a position-controlling method of CNTs was demonstrated in the optimum conditions of the TCVD.     

A New Transmission Line Microcavity Model for Vertical Cavity Surface Emitting Lasers

In this paper we present a new transmission line microcavity model for vertical cavity surface emitting lasers (VCSEL). The model is based on optical wave equations and implemented with state-space techniques to predict the lasing modes and analyze the decay properties of the Fabry-Perot (FP) cavities. The model is used to analyze microcavities in both time and frequency domains in terms of material and physical parameters of the lasers, and provide a simple and fast way to optimize the cavity length, reflective mirror and active region of the lasers.     

Turbulence modulation for gas - particle flow in vertical tube and horizontal channel using four-way Eulerian-Lagrangian approach

Turbulence modulation of gas-solid flow in vertical tube and horizontal channel in dilute and moderately dense suspensions is investigated numerically using a four way Eulerian-Lagrangian approach. Low Reynolds number k-l model is used for analyzing the fluid phase motion. A new model is presented based on a source-term formulation, which can predict fluid phase turbulence augmentation due to the presence of large particles and damping of turbulence due to small particles in the core of the channel and tube. Particle-particle and particle-wall collisions are simulated based on a deterministic approach, and coupling terms representing the fluid-particle interactions are also taken into account. The predicted fluid mean velocity and turbulence intensity profiles are in good agreement with the available experimental data. Additional numerical simulation results for variation of the eddy viscosity, turbulence production and dissipation are also presented for different values of loading ratios.     

Sensitivity of multi-angle photo-polarimetry to vertical layering and mixing of absorbing aerosols: Quantifying measurement uncertainties

The impact of tropospheric aerosols on climate can vary greatly based upon relatively small variations in aerosol properties, such as composition, shape and size distributions, as well as vertical layering. Polarimetric measurements have been advocated in recent years as an additional tool to better understand and retrieve the aerosol properties needed for improved predictions of aerosol radiative forcing on climate. The goal of this study is to introduce a formal approach to assessing the sensitivity of both intensity and polarization signals to absorbing aerosol layering, explicitly accounting for instrument measurement uncertainties. If ignored, sensitivity to aerosol height can introduce biases in aerosol property retrievals at short (ultraviolet or blue) wavelengths; if properly exploited, it may enable the extraction of some basic information on aerosol profiles. Employing a vector successive-orders-of-scattering (SOS) radiative transfer code, we conducted modeling experiments to determine how the measured Stokes vector elements are affected at 446 nm (blue band) by the vertical distribution, mixing and layering of smoke and dust aerosols under the assumption of a simple Lambertian surface and predefined aerosol microphysical properties. We find that smoke and dust vertical layering, if ignored, can introduce biases in radiometric and polarimetric aerosol property retrievals for aerosol optical depth (AOD) above 0.3 (polarimetric) and AOD above 0.5 (radiometric), and should, therefore, be accounted for in retrievals at high aerosol loadings.     

On the Geometry of the （1, 1）-Tensor Bundle with Sasaki Type Metric

Curvature properties are studied for the Sasaki metric on the (1,1) tensor bundle of a Riemannian manifold. As an application, examples of almost para-Nordenian and para-K(a)hler-Nordenian B-metrics are constructed on the (1,1) tensor bundle by looking at the Sasaki metric. Also, with respect to the para-Nordenian B-structure, paraholomorphic conditions for the complete lifts of vector fields are analyzed.     

A game theoretic approach to coordinate pricing and vertical co-op advertising in manufacturer-retailer supply chains

Vertical cooperative (co-op) advertising is a marketing strategy in which the retailer runs local advertising and the manufacturer pays for a portion of its entire costs. This paper considers vertical co-op advertising along with pricing decisions in a supply chain; this consists of one manufacturer and one retailer where demand is influenced by both price and advertisement. Four game-theoretic models are established in order to study the effect of supply chain power balance on the optimal decisions of supply chain members. Comparisons and insights are developed. These embrace three non-cooperative games including Nash, Stackelberg-manufacturer and Stackelberg-retailer, and one cooperative game. In the latter case, both the manufacturer and the retailer reach the highest profit level; subsequently, the feasibility of bargaining game is discussed in a bid to determine a scheme to share the extra joint profit.     

Field emission and x-ray effect on RAON half-wave resonator (HWR) superconducting cavity performance

Performance of superconducting cavities are investigated with field emission effect and x-ray detection. Conducting particles and surface curvature can cause field emission from the surface of the superconducting Nb cavity. The field emission makes the local temperature increase and the quality factor decrease. Vertical test is performed for half-wave resonator (HWR) cavities. The vertical test facilities are introduced and the quality factors are measured for the half-wave resonator (HWR) cavities. The quality factors of the cavities decrease as the x-ray are increased. The surface resistance and x-ray generation of the cavity can be fitted well with the field emission theory. The quality factor for the half-wave resonator (HWR) cavities decreases linearly with the field enhancement factor for x-ray generation.     

Nonlinear interfacial waves in a circular cylindrical container subjected to a vertical excitation

Singular perturbation theory of two-time scale expansions was developed in inviscid fluids to investigate the motion of single interface standing wave in a two-layer liquid-filled circular cylindrical vessel, which is subjected to a vertical periodical oscillation. It is assumed that the fluid in the circular cylindrical vessel is inviscid, incompressible and the motion is irrotational, a nonlinear amplitude equation including cubic nonlinear and vertically forced terms, was derived by the method of expansion of two-time scales without taking the influence of surface tension into account. By numerical computation, it is shown that different patterns of interface standing wave can be excited for different driving frequency and amplitude. We found that the interface wave mode become more and more complex as increasing of upper to lower layer density ratio γ$\gamma$. The traits of the standing interface wave were proved theoretically. In addition, the dispersion relation and nonlinear amplitude equation obtained in this article can reduce to the known results for a single fluid when γ=0,_h2→_h1$\gamma =0,h_2\to h_1$.     

Electrical control of valley and spin polarized current and tunneling magnetoresistance in a silicene-based magnetic tunnel junction

We investigate the electronic transport in a silicene-based ferromagnetic metal/ferromagnetic insulator/ferromagnetic metal tunnel junction. The results show that the valley and spin transports are strongly dependent on local application of a vertical electric field and effective magnetization configurations of the ferromagnetic layers. In particular, it is found that the fully valley and spin polarized currents can be realized by tuning the external electric field. Furthermore, we also demonstrate that the tunneling magnetoresistance ratio in such a full magnetic junction of silicene is very sensitive to the electric field modulation.