Claims
- 1. In a method for the analysis of a mixture of chromatography of said mixture on a gas chromatography column and passing the output from said column via an open-split interface into a mass spectrometer having a total ionization monitor, wherein the temperature of said column is progressively increased during said analysis from a lower temperature to an upper temperature and an inert gas is supplied to said open-split interface, the improvement which comprises heating said inert gas and said interface to a temperature at least about 10.degree. C. above said upper temperature, the temperature of said inert gas and said interface being maintained substantially constant as the temperature of said column is progressively increased, thereby preventing drift in the base line signal of said total ionization monitor of said mass spectrometer as the temperature of said column is progressively increased.
- 2. A method according to claim 1 wherein said inert gas and said interface are heated to a temperature not more than above said upper temperature.
- 3. A method according to claim 2 wherein said inert gas and said interface are heated to a temperature of about 25.degree. C. above said upper temperature.
- 4. A method according to claim 1 wherein said upper temperature is above about 200.degree. C.
- 5. A method according to claim 4 wherein said upper temperature is in the range of about 280.degree. to about 320.degree. C.
- 6. A method according to claim 1 wherein said mass spectrometer is provided with an oven and wherein said interface is thermally insulated from said oven.
Parent Case Info
This is a divisional of our co-pending application Ser. No. 306,942 filed Sept. 30, 1981 (now U.S. Pat. No. 4,391,778).
Foreign Referenced Citations (1)
Number |
Date |
Country |
708222 |
Jan 1980 |
SUX |
Non-Patent Literature Citations (3)
Entry |
Stan et al; Analy. Chem., vol. 50, No. 14, 12/1978, pp. 2161-2164. |
Henneberg et al, J. of Chrom., 167 (1978), 139-147. |
Henneberg et al, Chromatographia, vol. 8, No. 9, 9/1975, 449-451. |
Divisions (1)
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Number |
Date |
Country |
Parent |
306942 |
Sep 1981 |
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