The peak frequency of the dielectric loss angle of gas molecules adsorbed in a porous silicon gas sensor having a 2.4 nm pore radius is found to vary inversely proportional to the third power of the gas molecular radius. Peak frequency is extremely sensitive to the pore radius, becoming about one order of magnitude higher for a pore radius of 1 nm. The temperature dependence of the peak frequency in the range of 0 to 25 °C was also determined.

In a previous experiment, it was shown that a gas identification sensor using porous silicon necessitated more than 60% concentration for identification. In the present study, it was shown by means of an experiment using water vapor that the concentration limit for gas identification may be controlled by changing the sensor temperature. In addition, the possibility of quantitative analysis of gas identification in which the sensor temperature is taken as a new parameter was proposed.

In this work, we propose a new non-Abelian generalization of the Born-Infeld Lagrangian. It is based on a geometrical property of the Abelian Born-Infeld Lagrangian in its determinantal form. Our goal is to extend the Abelian secondtype Born-Infeld action to the non-Abelian form preserving this geometrical property, which permits us to compute the generalized volume element as a linear combination of the components of metric and the Yang-Mills energymomentum tensors. Under the BPS-like condition, the action proposed reduces to that of the Yang-Mills theory, independently of the gauge group. New instanton-wormhole solution and static and spherically symmetric solution in curved spacetime for an SU (2) isotopic ansatz are solved and the N = 1 supersymmetric extension of the model is performed.PACS numbers: 11.25.Hf, 12.60.JvRecently, interest has increased in this nonlinear electromagnetic theory since it turned out to play an important role in the development of string theory, as was very well described in the pioneering work of Barbashov and Chernikov [5]. The nonlinear electrodynamics of the Born-Infeld Lagrangian, shown in [24], describes the low-energy process on D-branes

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Porous silicon is formed by anodization of single crystalline silicon under various current densities and HF concentrations which are the important parameters for anodization. Anodization is carried out in HF solution at constant temperature under a constant current density distribution. This paper describes the fabrication process dependencies of dissolution valence, porosity, and layer formation efficiency which are related directly to the anodization conditions. In addition, the mechanical strength of porous silicon obtained by the hardness measurement was related to the self‐standing limit of porous silicon obtained by a cylindrical model for pores arranged in the twodimensional lattice.