Broad band arrays

Figure 13. Schematic lay-out of compact optical sensor chip without need of external optical apparatus with 4 different sets of sensing arrays. LED broad band source, for example Light Emitting Diode, MR-F microresonator used as optical filter, MR-S microresonator used as optical sensor, PD Photo Diode.

A broad band detector array with homogeneous sensitivity is achieved in JP-A-60102530 by providing a thin single crystal film of Hgi.xCd,Te having a concentration gradient of the composition ratio x. 

A more recent addition to the diverse array of x-ray based methods is x-ray absorption spectroscopy. In contrast to x-ray diffraction methods which derive their utility from the properties of well defined crystallites, x-ray absorption methods are atomic probes, capable of obtaining both electronic and structural information about a specific type of atom. The growing use of x-ray absorption methods is a result of the greater availability of synchrotron radiation sources which provide the intense broad band x-radiation required. In some instances laboratory based spectrometers utilizing either sealed tubes or rotating anode x-ray generators can also be used. 

This new design of nano chambers array on chips allows a broad band of measurements. We can simultaneously test eight different toxicant types with the general stress responsive promoter by introducing to each chamber a different toxicant, or, in order to specify unknown aqueous sample, we can test the sample with eight different stress responsive promoters. Thus we obtain an indication of the toxicant type. In addition, the array configuration enables the addition of positive and negative control chambers for each experiment. 

A tapered periodic surface (TPS) is an array of wire or slot type elements with element sizes and interelement spacings that vary as a function of position over the array. Many different appUcations of TPS come to mind. Most of these applications involve a smooth electrical transition to terminate the finite edge of an FSS or phased array. A TPS could also be used to transition from one FSS design to another in a radome with multiband window areas. Another application is as a building block for broad band and low side lobe antenna designs. Tapered Periodic Surfaces exhibit two fundamental properties ... 

Note in particniar that we are not interested in an array that without a ground-plane has a constant impedance over a broad band. On the contrary, we need an array impedance with a reactive part that can at least partly cancel the groundplane reactances at the npper and lower frequencies, respectively. 

Zhang J, Hughes WJ, Bouehilloux P, Mayer Jr. RJ, Uchino K, Newnham RE (1999) A elass V flextensional transdueer The cymbal. Ultrasonics 37 387-393 Zhang J, Hughes WJ, Mayer Jr. RJ, Uchino K, Newnham RE (2000) Cymbal array A broad band sound projeetor. Ultrasonics 37 523-529... 

Basic instrument configurations are shown in Figs. 1-5. Abbreviations used in the figures are BBS, broad band source EnS, entrance slit DE, dispersive element (grating or prism type) SS, second slit ExS, exit slit S, sample DET, detector PDA DET, photodiode array detector BS, beam splitter FM, fixed mirror MM, movable mirror NB-IF, narrow bandpass interference filter. 

The purpose of this chapter is to provide an overview of a rather wide array of experimental techniques that can tell us about the electronic structure of molecules. Some of these techniques, such as photoelectron (PE) spectroscopy, which is based on Einstein s photoelectric effect, are generally applied to gas-phase molecules. They can give high-resolution spectra, providing information about molecular vibrations and even, in a few cases, rotations. At the other end of the scale, UV/vis spectroscopy, particularly as applied to transition-metal complexes in solution, involves broad bands, and although it is an important and widely-used method, the information it gives is limited. Emission spectroscopy of transition-metal compounds has also become important. 

Often a broad-band laser (e.g., a pulsed dye laser without etalons), or a multiline laser (e.g., a CO2 or CO laser without grating) may simultaneously cover several absorption lines of different molecules. In such cases the reflected beam is sent to a polychromator with a diode array or an optical multichannel analyser (Sect.4.5). If a fraction of the laser power Po(w) is imaged onto the upper part of the OMA detector and the transmitted power onto the lower part (Fig. 15.10) electronic difference and ratio recording allows the simultaneous determination of the concentrations Nj of all absorbing species. A retroreflector arrangement is feasible for measurements at low altitudes above ground, where buildings or chimneys can support the construction. Examples are measurements of fluorine concentrations in an aluminum plant [15.55] or the detection of different constituents in the chimney emission of power plants, such as NO and SO components [15. 56]. Often ammonia is added to the exhaust of power stations in order to reduce the amount of emission. In such cases the optimum concentration of NH3 has to be controlled in situ. A recently developed detection system for these purposes has demonstrated its sensitivity and reliability [15.57]. 

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