DIFFERENTIAL X-RAY ABSORPTION SPECTROSCOPY SYSTEM

X-RAY SPECTROCHEMICAL ANALYSIS, IN CONJUNCTION WITH SCANNINGOR TRANSMISSION ELECTRON MICROSCOPY, IS OFTEN NOT USED BECAUSE CONVENTIONAL ENERGY-DISPERSIVE CRYSTAL DETECTORS ARE EXPENSIVE AND MUST BE MAINTAINED AT LIQUID NITROGEN TEMPERATURES. THESE ADD CONSIDERABLY TO THE EQUIPMENT PURCHASE PRICE AND TO A HIGH AND CONTINUING OPERATING COST. CRYO COMPONENTS ARE CUMBERSOME AND AWKWARD TO CONNECT TO SOME MODELS OF ELECTRON MICROSCOPES. R.J. LEE GROUP, INC., WILL DEVELOP A SIMPLE X-RAY DETECTOR BASED ON THE PRINCIPLES OF ABSORPTION X-RAY SPECTROSCOPY ANDPERSONAL COMPUTER TECHNOLOGY. THE KEY TO SUCCESSFUL IMPLEMENTATION OF THE TECHNIQUE WILL BE VERIFICATION THAT ABSORPTION FILTERS FOR THE LIGHTER ELEMENTS OF IMPORTANCE INBIOLOGICAL SYSTEMS CAN BE EFFECTIVELY CALIBRATED BY COMPUTER, ELIMINATING MANY OF THE PROBLEMS ASSOCIATED WITH THE PRECISE CONTROL OF FILM THICKNESS. THE CONCEPT IS BASED ON COUPLING DIFFERENTIAL X-RAY FILTERS WITH A POSITION-SENSITIVE DETECTOR AND ON-LINE COMPUTER PROCESSING OF THE COUNT RATES TO PROVIDE A DIRECT READOUT OF ELEMENTAL COMPOSITION ON ANYTHING FROM A PERSONAL COMPUTER TO AN ARRAY OF DIGITAL PANEL METERS. THE PHASE I PROJECT WILL DEMONSTRATE THE FEASIBILITY OF USING DIFFERENTIAL FILTERS TO IDENTIFY AND QUANTIFY CHARACTERISTIC X-RAYS. IN PHASE II, THESE TECHNOLOGIES WILLBE BROUGHT TOGETHER TO DEVELOP A DIFFERENTIAL ABSORPTION X-RAY SPECTROSCOPY SYSTEM FOR IDENTIFYING CHARACTERISTIC X-RAYS AND QUANTIFYING THEIR INTENSITIES. THIS WILL RESULT IN A SIMPLE AND PORTABLE X-RAY ANALYSIS SYSTEM.