wideband modulator for high switching speed frequency synthesiser

this paper describes a single sideband suppressed carrier modulator intended to produce fine frequency stepping on the output of a broadband synthesiser, operating from below 1 ghz to greater than 5 ghz. the digitally synthesised local oscillator in the 100-200 mhz range is in principle also capable of working broadband the modulator cons..

r-matrix calculation of the energy-positions of high-lying 4fnf j=5, 6 autoionising levels of barium

theoretical energy-positions of 4fnf j=5, 6 autoionising levels of barium are obtained by a combination of the eigenchannel r-matrix and the multichannel quantum defect theory (mqdt) methods high-lying 4fnf j=5, 6 levels (n>8) located below the ba/sup +/4f/sub 5/2/ threshold are investigated. the calculation accounts for the mixing of 4fn..

trends in insulated rectangular copper conductors for electrical machines

strips used for windings of large electrical machines are an important material. developments in 'material science' and manufacturing techniques have helped the winding strip to come a long way from the cotton covered cu strips used some decades ago to enamelled, dual coated, fibreglass, kapton, polymica covered, as well as 'composite' in..

the nonplanar amide group in n-acylaziridines' conformational behavior and chiroptical properties

chiroptical properties in the intrinsically dissymmetric amide chromophore of n-acylaziridines are investigated experimentally and by ab initio molecular orbital calculations. computations on n-formylaziridine (1a) and measurements of the cd spectra of (1r, 2r)-1-acetyl-2-methylaziridine (1b), (1r,2r)-1-( alpha -hydrohexafluoroisobutyryl)..

IR spectroscopic study of the structural transformations of cellulose during its nitration

cellulose nitrates (n) are practically important polymers which combine valuable operating qualities with comparatively simple fabrication technology and wide availability of the raw material the structural changes which take place in cellulose during nitration were investigated by ir spectroscopy combined with mathematical processing of ..

eigenchannel r-matrix study of the j=0 and j=2 even parity spectra of calcium below the ca/sup +/ 3d/sub 3/2/ threshold

the j=0 and j=2 even parity spectra of calcium are studied through a combination of the eigenchannel r-matrix and multichannel quantum defect (mqdt) methods. the bound and autoionizing spectra below the 3d/sub 3/2/ threshold are investigated. the calculation reproduces well the perturbations of the 4sns /sup 1/s/sub 0/ , 4snd /sup 1.3/d/s..

safety assessments' achievements and perspectives in the cec programmes

the paper recalls, in short, some of the main features of the pagis methodology and presents some of the main results obtained by implementing the methodology to the disposal of high level waste the sensitivity studies are outlined and some of the most important parameters identified. the main conclusions of the assessments are also drawn..

thermally forced gravity in an atmosphere at rest

the transient linear response of a quiescent, two-dimensional, nonrotating atmosphere to prescribed heat sources and sinks is investigated. analytical solutions of the hydrostatic boussinesq equations are obtained for a rigid lid and for a semi-infinite region for heating profiles characteristic of both convective and stratiform regions. ..

eigenchannel r-matrix calculation of the even-parity 6 pnp and 6 pnf j=0,1, 2 autoionizing levels of barium

a detailed comparison between theoretical calculations and recent experiments on laser-excited 6 pnp and 6 pnf j=0, 1, 2 autoionizing levels of ba is presented. all observables are calculated by a combination of the eigenchannel r-matrix and the multichannel quantum defect theory (mqdt) methods. mqdt analyses of the energy positions of th..

a simplified method for determining the number of independent slip systems in crystals

describes a method of determining the number of independent slip systems for any family or combination of families of slip systems which is more direct than previous approaches. specifically, if the operative slip system(s) are known for a material, one may determine in a straightforward manner if the material is slip system-deficient by ..