Insert Experiment Steps

Injection Type [group box]:

• Inject loop gas. [button] Automatically injects the contents of the loop into the path that leads to the sample. The contents of the loop are pushed out of the loop by the carrier gas.

• Manual injection. [button] Prompts the user to inject a dose of gas into the septum using a syringe.

After Injection. Specify the amount of time to wait after injection has occurred.

Description. [text box] Description of the experiment.

Type of analysis. [drop‑down box]

If Pulse Chemisorption is selected, the Stoichiometry button is enabled. When modifying the Active Metals table during the insertion of a Pulse Chemisorption experiment, changes to the Active Metals table on the Sample Description tab are not affected. This is useful when sequencing multiple experiments and Stoichiometry is different from one experiment to the next.

Bath temperature. [text box] Applies to Physisorption Surface Area only. Calculates P₀ using the entered bath temperature.

Stoichiometry. [button]Opens the Active Metals table. Specify the percent of sample weight of the active metals in the sample and the stoichiometry factor. See Active Metals for Chemisorption Analyzers.

Vapor. [check box] If Temperature Programmed, Pulse or Other is selected, the Vapor checkbox is enabled and a drop-down list is displayed. Select the Vapor to be used

Use to calibrate the TCD so that peak areas can be converted to gas quantities. During a gas calibration, a series of known gas mixtures flows through the analyzer and the resultant signal readings are recorded. The analyzer can then use these data to calculate the concentrations of unknown mixtures flowing past the detector during subsequent analyses.

Calibration Gases. [drop‑down box] Select the Carrier and Loop gases to be used in this calibration. The gases available are those specified in an Adsorptive Properties [.ADP] file.

• Reference flow rate. [text box] Enter a flow rate for the calibration gases.
• Maximum active gas concentration. [text box] Enter the maximum percentage for the active gas concentration.

Description. [text box] Description of the experiment.

Detector block. [text box] Enter the temperature for the detector block.

Filament temperature. [selection] Enter the temperature for the filament.

Set external trigger. [check box] If selected, the contact closure used to trigger an external mass spectrometer will be activated. If deselected, the contact closure will be deselected.

Valves. [selection] Enter the temperature for the valves.

As instrument settings are changed in the left window, changes are highlighted on the schematic at the bottom right window.

Gas Flow. [group box] Select the gases to be used in this analysis along with the flow rates. The gases available are those specified in an Adsorptive Properties [.ADP] file. See Adsorptive Properties and Gas Charts for gas combinations. Indicate if a Different reference rate should be used along with the applicable rate.

Flow Path. [group box] Select the step to be performed at each valve.

Temperature. [group box] Enter the sample and rate temperatures.

• Disable temperature control. [button] Disables the temperature control.

• Disable vapor heating. [check box] Disables the vapor flask heating mantle, the vapor reflux zone heater, and the vapor block heater.

• Return to ambient temperature. [button] Allows the furnace temperature only (not the sample temperature) to return rapidly to a temperature between 14 °C and 50 °C.

Detector [group box]:

• Block temperature. [text box] Enter the block temperature.

• Enable detector. [check box] Specify if the detector should be enabled and the applicable Filament Temperature.

Use to verify the volume of the loop for use in calculations on analyses that use the loop. Sample analysis data yield signal vs. temperature data and peak areas. Associating the sample file with a loop calibration file makes it possible for the application to convert sample data to volume values.

Calibration Gases. [drop‑down box] Select the Carrier and Loop gases to be used in this calibration. The gases available are those specified in an Adsorptive Properties [.ADP] file. Enter a Flow rate for each gas.

Description. [text box] Description of the experiment.

Filament temperature. [selection] Enter the temperature for the filament.

Number of injections. [text box] Enter the number of manual and automatic injections (3-10) to be done with the loop during calibration.

Temperature. [group box] Enter the temperatures for the Detector block and valves.

Specifies how frequently the signal reading is recorded. A Stop Recording step is inserted in the steps automatically when a Start Recording step is inserted. Multiple steps can be inserted between the Start Recording and Stop Recording steps.

One measurement every [n] seconds.[text box] Specify the frequency of measurements.

Set external trigger. [check box] If selected, the contact closure used to trigger an external mass spectrometer will be activated. If deselected, the contact closure will be deselected. If this option is enabled, the external trigger signal will be set at the beginning of recording and turned off at the end of recording.

Specifies the duration of the repeat sequence. Automatically inserts a Start Repeat and a Stop Repeat in the list of steps. Multiple experiment steps can be inserted within the Repeat loop.

Repeat until peaks are equal or [n] times. [button] Stops repeating the steps within the loop when the last two peaks are equal to within 5% of the area, or when the maximum number of repeats is reached. This option is useful when performing H₂ or CO pulse chemisorption on supported metal catalysts.

Repeat until peaks are zero or [n] times. [button] Stops repeating the steps within the loop when the last two peaks are each less than 10% of the area of the first peak, or when the maximum number of repeats is reached. This option is useful when performing an N₂O decomposition for characterizing copper catalysts.

Repeat [n] times. [button] Stops repeating the steps within the loop when the specified number of times is reached.

Repeat until peaks match the first peak or [n] times. [button] Stops repeating the steps within the loop when the last two peaks each match the first peak to within 10% of its area or when the maximum number of repeats is reached.

Changes the sample temperature.

Ramp Type [group box]:

End temperature. [text box] The ending temperature for the ramping procedure. If the CryoCooler is installed, it is automatically enabled if an ending temperature below 20 °C is used.

Hold time. [text box] Temperature at which the sample is to be held while degassing.

Ramp rate. [text box] The rate at which the temperature will change while advancing to the hold temperature.

Description. [text box] Enter a description for this step.

Carrier Gas. [group box] Select the carrier gas and enter the Flow rate.

Insert. [button] Inserts a new row at the top of the table.

Delete. [button] Deletes the currently selected row.

Reset. [button] Resets the table, returning it to the layout before the dialog box is closed.

Append. [button] Adds a new row to the bottom of the table.

Carrier Gas/Loop Gas. [drop‑down box] Select the gases to be used for this step and enter the Flow rate.

Description. [text box] Enter a description for this step.

Flask Temperatures. [group box] Enter a value between 20.0 and 120.0 degrees as the Minimum and Maximum.

Filament temperature. [selection] Enter the temperature for the filament.

Number of steps. [text box] Enter the number of steps (between 3 and 7) for this calibration.

Reflux Temperatures. [group box] Enter a value between 20.0 and 100.0 degrees for the Minimum and Maximum.

Set external trigger. [check box] If selected, the contact closure used to trigger an external mass spectrometer will be activated. If deselected, the contact closure will be deselected.

Temperature. [group box] Enter a value between 20.0 and 150.0 degrees for the Valves and Detector block.

Vapor. [drop‑down box] Select the vapor to be used.

Specify a waiting routine.

Wait [n] minutes. [button] Specify the time to wait.

Wait for operator. [button] Enter a description of the operator task. During an analysis, the entered message displays at the appropriate time. The analysis continues after the operator clicks OK.

Wait until baseline and temperature are stable. [button] Specify if the analysis should wait until the baseline and temperature become stable,  then click Baseline to specify the settings.

Wait for change from baseline or [n] minutes. [button] Specify the time to wait, click OK, then click Baseline to specify the settings.

Wait for return to baseline. [button] Waits for a return to baseline. If enabled, click OK, then click Baseline to specify the settings.