Varian 450-GC, User Manual

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Table of Contents Table of Contents
Page: Page: XX XX User User Manual Manual 450-GC 450-GC Varian, Varian, Inc. Inc.
ELECTRON CAPT ELECTRON CAPTURE DETECTOR ( URE DETECTOR (ECD) ECD) .... ............................................................................ ........................................................................329 329
Initial Set-up.... Initial Set-up...................................................................................................................... ..................................................................................................................330 330
ECD Adjustments .... ECD Adjustments ............................................................................................................. .........................................................................................................331 331
Cell- Cell-Curre Current nt .... .................................................................................................................. ..............................................................................................................331 331
Time Time Constant Constant Switch Switch .... .................................................................................................. ..............................................................................................331 331
Setting the Contact Potential.... Setting the Contact Potential........................................................................................ ....................................................................................332 332
ECD ECD Operation Operation.... ............................................................................................................. .........................................................................................................333 333
Column a Column and Septum nd Septum Bleed Bleed .... .......................................................................................... ......................................................................................333 333
Column Conditio Column Conditioning ning.... .................................................................................................... ................................................................................................333 333
Column Oven and Detec Column Oven and Detector Oven Temperature Selecti tor Oven Temperature Selection on .... .......................................... ......................................333 333
ECD Pneumatics .... ECD Pneumatics .............................................................................................................. ..........................................................................................................334 334
Installation Installation/Disassembly /Disassembly .... ................................................................................................... ...............................................................................................335 335
Exploded Exploded View View .... .................................................................................................................. ..............................................................................................................335 335
ECD In ECD Installation stallation.... ................................................................................................................ ............................................................................................................337 337
M M
AINTENANCE AINTENANCE
.... ......................................................................................................................... .....................................................................................................................340 340
Thermal Cleaning With Carrier Gas .... Thermal Cleaning With Carrier Gas ................................................................................. .............................................................................340 340
PULSED FLAME PHOTOMETRIC DETECTOR (PFPD).... PULSED FLAME PHOTOMETRIC DETECTOR (PFPD)......................................................... .....................................................343 343
Description.... Description........................................................................................................................ ....................................................................................................................343 343
Basic Components of the PFPD.... Basic Components of the PFPD....................................................................................... ...................................................................................343 343
Features of th Features of the PFPD Assem e PFPD Assembly bly .... ...................................................................................... ..................................................................................344 344
Features of the PFPD Features of the PFPD Electromete Electrometer Board.... r Board....................................................................... ...................................................................346 346
Theory of Oper Theory of Operation of the PFPD ation of the PFPD .... ..................................................................................... .................................................................................346 346
Stages of Flame Pulsation.... Stages of Flame Pulsation................................................................................................ ............................................................................................347 347
How Does the PFPD Achieve its How Does the PFPD Achieve its Greater Detectivity and Selectivity?.... Greater Detectivity and Selectivity?............................. ......................... 348 348
Background Emission in a Pulsed-flame.... Background Emission in a Pulsed-flame...................................................................... ..................................................................348 348
Time-depe Time-dependence of ndence of Emission Profiles.... Emission Profiles........................................................................ ....................................................................348 348
Emission Profiles.... Emission Profiles.......................................................................................................... ......................................................................................................348 348
Concentration (in time) of the Emitted Light.... Concentration (in time) of the Emitted Light.... ............................................................. .............................................................349 349
Separation of the Element Emission from Separation of the Element Emission from Background Emission.... Background Emission................................ ............................ 349 349
Effect of Gate Control.... Effect of Gate Control................................................................................................... ...............................................................................................350 350
Adjustment o Adjustment of the Gas Com f the Gas Composition.... position............................................................................. .........................................................................351 351
PFPD Flo PFPD Flow Path w Path .... ............................................................................................................... ...........................................................................................................351 351
References .... References ....................................................................................................................... ...................................................................................................................352 352
Specifications.... Specifications.................................................................................................................... ................................................................................................................352 352
Installation.... Installation......................................................................................................................... .....................................................................................................................354 354
Inspecting the PFPD.... Inspecting the PFPD......................................................................................................... .....................................................................................................354 354
PFPD Accessory Kit .... PFPD Accessory Kit ......................................................................................................... .....................................................................................................354 354
PFPD Diffusion Source Kit .... PFPD Diffusion Source Kit ............................................................................................... ...........................................................................................355 355
Installing a Chromatographic Column .... Installing a Chromatographic Column .............................................................................. ..........................................................................356 356
Prepare the Co Prepare the Column End lumn End .... .................................................................................................. ..............................................................................................356 356
Disassemble the PFPD.... Disassemble the PFPD..................................................................................................... .................................................................................................357 357
Remove the Detector Tower (Optional).... Remove the Detector Tower (Optional)............................................................................ ........................................................................359 359
Insert the Column .... Insert the Column ............................................................................................................. .........................................................................................................360 360
Reassemble Reassemble the PFPD the PFPD .... ..................................................................................................... .................................................................................................361 361
Operatio Operation n .... ......................................................................................................................... .....................................................................................................................363 363
Adjusting the Adjusting the Gas Flow Ra Gas Flow Rates tes .... .......................................................................................... ......................................................................................363 363
Split Valve.... Split Valve......................................................................................................................... .....................................................................................................................363 363
PFPD Gas Flow Diagram with EFC15.... PFPD Gas Flow Diagram with EFC15.............................................................................. ..........................................................................364 364