Decomposition of Benzene Using Ag/TiO2 Packed Plasma-Driven Catalyst Reactor: Influence of Electrode Configuration and Ag-Loading Amount

This paper describes the effects of electrode configuration and the loading amount of Ag catalyst on the decomposition of gas-phase benzene using plasma-driven catalyst (PDC) reactors. Modification of ground electrode brought out a great enhancement in the energy efficiency for benzene decomposition by reducing abnormal discharges outside the reactor tube. The data of carbon balance and the selectivity of CO₂ indicated that the Ag catalyst played an important role in the decomposition of benzene, especially for the intermediates. The larger the Ag-loading amounts on the TiO₂, the better the performance of benzene decomposition in terms of the carbon balance and the selectivity of CO₂. Formation of NO₂ and N₂O indicated that the maximum specific input energy applicable to the PDC reactor should be determined not only by the decomposition efficiency but also by the formation of nitrogen oxides.     

Lightning protection of overhead power distribution lines

There are two major protective methods against lightning outages on overhead distribution lines. One is by use of surge arresters and the other is by an overhead ground wire. Surge arresters have rather constant effect regardless of the type of lightning outage causes. On the other hand, the effect of an overhead ground wire is quite different against the two major causes: direct lightning hit and induced overvoltages. This paper shows how to design lightning protection for overhead power distribution lines taking these characteristics into account. Copyright © 2007 Institute of Electrical Engineers of Japan. Published by John Wiley & Sons, Inc.     

基于三维人脸成像系统的复数域人脸识别方法

三维人脸识别是模式识别和人工智能领域的研究热点。提出了一种利用人脸图像的二维灰度信息和三维深度信息进行人脸识别的算法。首先利用相关型图像传感器构成三维实时人脸成像系统,并将获得的三维人脸物理数据用复数形式表达。再将特征脸（Eigenface）方法和Fisherface方法拓展到复数域,提出了复数域特征脸方法和复数域Fisherface方法。改进的复数域人脸识别方法在三维实时成像系统的人脸数据库中进行的人脸识别实验表明,复数域的三维人脸识别方法明显优于传统的人脸识别方法。     

Single-Component Pheromone Consisting of Bombykal in a Diurnal Hawk Moth, <Emphasis Type="Italic">Neogurelca himachala sangaica</Emphasis>

Recent work has suggested that hawk moths share pheromone components but are sexually separated by qualitative and quantitative differences in their pheromone blends. During field assays on the sex pheromones of other species, a diurnal hawk moth, Neogurelca himachala sangaica (Lepidoptera: Sphingidae), was frequently captured, but the composition of the sex pheromone of this species was not known. Analysis of hexane extracts of the pheromone glands of calling female by gas chromatography (GC) using an electroantennographic detector (EAD) revealed two components that elicited EAD responses from male moth antennae. These components were identified by their mass spectra and retention indices on two GC columns as (10E,12Z)-10,12-hexadecadienal (E10,Z12–16:Ald) and a trace of its (10E,12E)-isomer (E10,E12–16:Ald) in 98:2 ratio. In field experiments, E10,Z12–16:Ald alone attracted male moths, and addition of E10,E12–16:Ald significantly reduced the attractiveness, even at the naturally-occurring ratio. Analysis of the data using a generalized linear mixed model showed that E10,Z12–16:Ald positively contributed to attractiveness, whereas E10,E12–16:Ald did so negatively, and it was concluded that the sex pheromone of N. himachala sangaica consists solely of E10,Z12–16:Ald, bombykal. The negative effect of E10,E12–16:Ald on attractiveness could promote the species-specificity of this single-component pheromone system.     

Chain packing in graphs

This paper discusses the complexity of packingk-chains (simple paths of lengthk) into an undirected graph; the chains packed must be either vertex-disjoint or edge-disjoint. Linear-time algorithms are given for both problems when the graph is a tree, and for the edge-disjoint packing problem when the graph is general andk = 2. The vertex-disjoint packing problem for general graphs is shown to be NP-complete even when the graph has maximum degree three andk = 2. Similarly the edge-disjoint packing problem is NP-complete even when the graph has maximum degree four andk = 3.     

Phase-diagram study for the Al2O3-CaF2-SiO2 system

Phase relations for the Al₂O₃-CaF₂-SiO₂ system were investigated from 1673 to 1723 K. The hotfilament technique was applied to observe a two-liquid region and liquidus for the ternary system. The liquidus saturated with SiO₂ was investigated at 1673 K by using the hot-filament technique and the chemical equilibrium technique. In this system, the addition of Al₂O₃ to the CaF₂-SiO₂ system reduces the congruent temperature. A small substitution of Al₂O₃ for CaF₂ increases the solubility of SiO₂, namely, if the region of liquid phase could be enlarged. These results suggest that Al₂O₃ would be an effective substitute of CaF₂ in slag for steelmaking.     

Numerical nonlinear observers using pseudo‐Newton‐type solvers

In constructing a globally convergent numerical nonlinear observer of Newton‐type for a continuous‐time nonlinear system, a globally convergent nonlinear equation solver with a guaranteed rate of convergence is necessary. In particular, the solver should be Jacobian free, because an analytic form of the state transition map of the nonlinear system is generally unavailable. In this paper, two Jacobian‐free nonlinear equation solvers of pseudo‐Newton type that fulfill these requirements are proposed. One of them is based on the finite difference approximation of the Jacobian with variable step size together with the line search. The other uses a similar idea, but the estimate of the Jacobian is mostly updated through a BFGS‐type law. Then, by using these solvers, globally stable numerical nonlinear observers are constructed. Numerical results are included to illustrate the effectiveness of the proposed methods. Copyright © 2007 John Wiley & Sons, Ltd.     

Crystal growth of MgAlB14-type compounds using metal salts and some properties

LEAlB₁₄ (orthorhombic, Imam) (LE = Li, Mg) crystals were grown using metal salts (Li₂CO₃, LiF, LiI, MgO, MgF₂, MgI₂) and crystalline boron from a high-temperature aluminium metal flux. The growth conditions for growing LEAlB₁₄ were established using the starting mixtures of B/LE = 2.0, and Al metal was added to each mixture at a mass ratio of 1:15–20. LEAlB₁₄ crystals from the Al-self flux using metal salts could be obtained from all the different salts. The maximum dimensions of LiAlB₁₄ and MgAlB₁₄ crystals were approximately 18 and 12 mm for the crystals obtained from LiF and MgF₂. The unit-cell parameters of as-grown LEAlB₁₄ are as follows: for LiAlB₁₄, obtained from LiF, a = 0.5846 (2) nm, b = 0.8144 (2) nm, c = 1.0355 (3) nm, V = 0.4930 (2) nm³: for MgAlB₁₄, obtained from MgF₂, a = 0.5845 (2) nm, b = 0.8114 (2) nm, c = 1.0330 (3) nm, V = 0.4899 (3) nm³. Microhardness, oxidation resistance and magnetic susceptibility of these materials are described in detail.