Characteristics of Add Drop Filter using single and dual PCRR in square lattice

A Photonic Crystal Ring Resonator (PCRR) based Add Drop Filter is designed using two dimensional (2D) square lattice PC silicon rods in air host. The normalized transmission spectra for a single-ring and dual-ring configurations have been investigated using 2D Finite Difference Time Domain (FDTD). The filter characteristics such as coupling efficiency, dropping efficiency, resonant wavelength and Q factor are numerically analyzed for single ring and dual ring PCRR. It is noted that the coupling efficiency, dropping efficiency and Q factor of single ring circular PCRR with scatterer rod are 100%, 100% and 186.75, respectively. The backward dropping is observed in single ring PCRR whereas forward dropping are noticed in dual ring PCRR based ADF. The Photonic Band Gap (PBG) with respect to structural parameters such as the radius of the rod, lattice constant and refractive index difference, and propagation modes in periodic and nonperiodic structure are calculated by Plane Wave Expansion (PWE) method.     

An Improved Double Stage Furnace for Speciatton and Quantitative Atomic Absorption Spectrometry

Atomic absorption using furnace atomization suffers from three major problems. First, the matrix causes a change in absorption signal, second, the decomposition products cause a very high, variable background, and third, volatile elements are often lost during the evaporation and ashing steps. These problems are significantly reduced using the double stage system described below.

It consists of a separately heated atomization section, and vaporization section; and a light path which does not pass through the atomization section. This reduces background. The system operates in three modes. With the atomization section hot and the sample placed in the vaporization section, the latter is heated rapidly. This gives a fast quantitative signal with reduced background. With the atomization section cold, the sample is heated leisurely. The metal     

Differential forms,spin-3/2 fields and Einstein's equations

The relationship between Einstein's vacuum field equations and classical spin-3/2 field equations is re-explored using two-component spinor valued differential forms. One-form and two-form expressions for spin-3/2 fields and their field equations are considered and a Lagrangian formulation is presented. Complex structures defined by spin-3/2 fields are considered.     

Die potentiometrische Einstellung von Titantrichloridl?sungen

Ohne Zusammenfassung