We investigate how the qualitative structure of Doppler peaks in the angular power spectrum of the cosmic microwave anisotropy is affected by basic assumptions going into theories of structure formation. We define the concepts of “coherent” and “incoherent” fluctuations, and also of “active” and “passive” fluctuations. In these terms inflationary fluctuations are passive and coherent while topo...

The potential value of an oscillating-mirror rapid-scanning spectrometer as a detector for simultaneous multi-element emission spectrometry is demonstrated. A microwave argon plasma was used as the emission source with a carbon cup sampling device for analyte introduction. Analy tical graphs for bismuth, cadmium, manganese and magnesium prepared sirnulta neously are shown. The sensitivity of th...

In this paper, we present our progress toward designing a “smart” high-peak power microwave (HPM) tube. We use iterative learning-control (ILC) methodologies in order to control a repetitively pulsed high-power backward-wave oscillator (BWO). The learning-control algorithm is used to drive the error between the actual output and its desired value to zero. The desired output may be a given power...

Thermal conductivity of multiwalled carbon nanotubes ~CNT’s! prepared using a microwave plasma chemical vapor deposition system is investigated using a pulsed photothermal reflectance technique. We find that the average thermal conductivity of carbon nanotube films, with the film thickness from 10 to 50 mm, is around 15 W/m K at room temperature and independent of the tube length. Taking a smal...

EZ, E,^, EP Results are reported from preliminary tests to evaluate the high power microwave electrothermal thruster (MET) fr concept, which employs a free-floating plasma discharge maintained by applied continuous wave (CW) microwave Hz, H,^, HP power to heat a propellant gas flow. Stable plasmas were created and maintained in helium (He), nitrogen (N 2), and hydrogen (H2) as propellants in bo...

The present study was carried out to quantitatively analyze the levels of six potentially toxic heavy metals viz., arsenic (As), lead (Pb), cadmium (Cd), mercury (Hg), chromium (Cr) and nickel (Ni) in ten important Indian medicinal plants. The air dried powdered plant materials were subjected to microwave assisted wet digestion for the preparation of test samples. The samples were analyzed by u...

A 14.5 GHz ECRIS has been designed and fabricated at KAERI (Korea Atomic Energy Research Institute) to produce multi-charged ion beam (especially for C ion beam) for medical application. The magnet system has cupper conductor solenoid coils and a permanent magnet hexapole. A welded tube with aluminium and stainless steel is used for an ECR plasma chamber to improve the production of secondary e...

Helium microwave-induced plasma (He-MIP) for trace element analysis is generated by a 2.45 GHz microwave power ( ~ 1 kW) with the Okamoto cavity of the surface wave mode at atmospheric pressure, and an iron excitation temperature and an electron density of the plasma are measured. With 0.8 kW input microwave power, an excitation temperature of 8000 K and the electron density of 2 x 10/cm are ob...