NASA/Ames Research Center, JA:M/S 241-1, Moffett Field, CA 94035-1000

66 -- GAS CHROMATOGRAPH/VISCOUS INLET/ISOTOPE MASS SPECTROMETER SOL RFO2-36307 -- MMH DUE 090897 POC Micheli Hull, Contract Specialist, Phone (650) 604-1751, Fax (650) 604-4646, Email mhull@mail.arc.nasa.gov WEB: Click here for the latest information about this notice, http://procurement.nasa.gov/EPS/ARC/date.html#RFO2-36307 -- MMH. E-MAIL: Micheli Hull, mhull@mail.arc.nasa.gov. THIS NOTICE CONSTITUTES AMENDMENT NO. 01 TO THE COMBINED SYNOPSIS/RFO FOR GAS CHROMATOGRAPH/VISCOUS INLET/ISOTOPE MASS SPECTROMETER PREPARED IN ACCORDANCE WITH FAR PART 12.6 AS SUPPLEMENTED WITH ADDITIONAL INFORMATION CONTAINED IN THIS NOTICE. Companies shall acknowledge all amendment(s) in their offer. This notice serves as the official amendment to the subject solicitation and a written amendment will not be issued. The purpose of this amendment is to revise the following technical specifications #3, #5, #6, #10, #11, #14, #16, #17, #18 and insert #15: 3) The mass spectrometer will perform high-precision stable isotope analyses of the gases carbon dioxide, nitrogen, oxygen and hydrogen. For greater than 10 determinations of either carbon dioxide or nitrogen, the standard deviation should be within a factor of four of the shot noise limit. 5) The mass spectrometer must have a sensitivity for carbon dioxide and nitrogen of greater than 5x10E-4 ions per molecule, measured at the ion collector, with a Heflow rate into the source of 200 microliters per minute. 6) The high vacuum part of the system must be constructed with ultra-high vacuum components only, with all-metal gaskets. The mass spectrometer will have a stable background pressure of less than 2x10E-9 torr, without the use of cryogenic or chemical trapping. 10) Regarding accuracy, when 10 injections of propane or other gaseous hydrocarbon are interspersed with standard gas with time spacings in the 1 to 10 min range, the GCCMS system should deliver del13C values of propane, relative to the averaged value of the standard, that should not differ from the accepted value by more than 3 standard deviations. The average del15N value for 20 peaks of atmospheric nitrogen recorded at 1 min intervals should be within 0.1 permil of 0. 11) Regarding preservation of chromatographic resolution during transport of species through the GCCMS interface, using typical commercially available capillary GC columns, baseline resolution must be achieved for pristane and phytane from nC17 and nC18 alkanes, respectively. 14) The following specifications (enumerated and described above) must be demonstrated by a representative of the vendor in post-delivery tests: 3,4,5,6,9,10,11,12, and 13. 15) The mass spectrometer and vacuum system should be compatible with eventual delta D measurements to be made with the He flow from the GC-combustion interface. 16) The computer and software (C and S) must run the mass spectrometer and the viscous and GCC inlet systems. It should support automated operation with the elemenal analyzer (Carlo Erba Model EA1108), supplied by customer). The C and S must accomplish the injection of known reference gases at preprogrammed intervals for calibration purposes. 17) The computer and software (C and S) must be Windows NT-based and menu-driven. It must support measurements of sensitivity, abundance sensitivity, precision, accuracy, linearity, peak top flatness, V/F converter stability, and magnet and high voltage power supply stability. The C and S must display outputs of FID together with either the MS major ion beam or the calculated isotopic ratio, and it should include automated routines for background correction. The C and S must support post-analysis corrections for background, drift, blanks, and reference isotopic compositions. It should reduce the data to a form which can be exported to a spreadsheet program such as Microsoft Excel or equivalent. The customer will receive free upgrades of this Windows NT-based software for a period of up to 12 months following the successful installation of the complete isotope mass spectrometer system. The due date for receipt of offers is extended to 09/08.97. No changes to the terms and conditions. Offers shall provide the information stated in the synopsis/RFO posted on the NASA Acquisition Internet Service (NAIS)and published in the CBD on August 28, 1997. Documents related to this procurement are available over the Internet and are in Rich Text format and reside on the World-Wide Web (WWW) server which may be accessed using a WWW browser application. The WWW address or URL of the NASA/ARC Business Opportunities home page is http://procurement.nasa.gov/EPS/ARC/class.html. (0237)

Loren Data Corp. http://www.ld.com (SYN# 0281 19970827\66-0012.SOL)