ATI/Unicam 929 Spectrometer

1.1 Turn on Exhaust Fan

1.2 Verify that the correct hollow cathode lamp is in each turret position to be used for this experiment

1.3 Turn on the AA instrument (front panel switch) and the computer (power distribution strip)

2. Computer Operation to Open up SOLAAR Operating System

[Note: whenever the procedure selects a screen item, the action taken is to move the mouse pointer to the item and click once with the left mouse switch. Alternatives will be mentioned in the text, (e.g., double-click, use the right mouse switch, etc.)]

2.1 From the Program Manager Window, select "SOLAAR AA SYSTEM" ICON (mouse select & double-click)

2.2 From next screen, select "SOLAAR" ICON (mouse select & double-click)

The next screen is the "SOLAAR" working window for the AA Spectrometer. All of the operating parameter windows are cascaded on the screen. Any of these windows can be pulled to the top of the cascade by moving the mouse pointer to the top bar and clicking on it. Any of the operating windows can be removed from the screen and "iconized" down at the bottom of the screen for easy retrieval by clicking on the (down arrow) in the upper right corner of the window.

3. Setting Up the SOLAAR System for AA Measurements

3.1 Move the mouse pointer to the Commands Bar at the top of the screen, and select the [WINDOW] command; from the drop-down menu, select the [Tidy Up] button. (This procedure "iconizes" all of the cascaded operating windows previously on the screen, and places them at the bottom of the screen for selected retrieval.)

3.2 Move the pointer to the left side of the Top Commands Bar, and select the [FILE] command; from the drop-down menu, select the [LOAD] command; from the drop-down menu displayed, select [Analysis Parameters]; from the list of files, select the operating file prepared for the particular analysis (e.g., for the Chem 55 Mn determination, select the file entitled "55MNLSQR.PAR"; move the pointer and select [OK]. (This file installs all the pre-determined operating parameters.)

3.3 Move the pointer to the left side of the Top Commands Bar, and select the [FILE] command; from the drop-down menu, select the [LOAD] command; then select [Sequence Parameters]; from the list of files select the operating file prepared for the particular analysis (e.g., for the Chem 55 Mn determination, select the file entitled "55MNLSQR.TSK"; move the pointer and select [OK]. (This file will be loaded and all the pre-determined analytical sequence parameters will be installed.) (e.g., calibration w/ 5 standards, followed by determinations of 2 unknown samples; using a least squares calibration curve).

3.4 Select the [SPECTROMETER] ICON from the bottom of the screen (mouse select & double-click). Move the pointer to the Top Commands Bar and select the [SPECTROMETER] command; the drop-down menu will display selections; select [Parameters]; then select [Lamps].

3.5 From the displayed Lamps window, determine that the lamps assigned to the positions in the turret are correct. If not, select the [DEFINE] button and select specific elements from the displayed periodic table for the specific turret positions. If the lamps assigned are correct, and if their respective status boxes have an "X" in them, select the [CLOSE] button, and proceed to the next step. If the status boxes are clear, the lamps are not yet turned on; then move the pointer to the box for each lamp to be turned on for the respective analytical procedure, and click once. (e.g., for the Mn determination both the [Mn] and the [Deuterium] lamps should be turned on. When the status blocks are set appropriately, select the [CLOSE] button, and proceed to the next step.

3.6 To prepare the screen for operation of the spectrometer for several analyses:

move the pointer to the Top Commands Bar and select the [WINDOW] command; from the drop-down menu select [Load Positions]; from the displayed files select the one pertaining to the experiment to be done (e.g., for the Chem 55 Mn determination, select "55MNLSQR.FMT"); select [OK]. Again move the pointer to the Top Bar and select the [WINDOW] command; from the drop-down menu select [Arrange Icons]. (This last action will move all the iconized windows to the area of the screen left open by the preceding selections.)

3.7 From the Top Commands Bar select [ACTIONS]; then select [SET UP OPTICS]. The system responds with a Screen Command "Move Turret to Position No. 'N'". If the turret is already in position, select the [OK] button; if not, open the hinged door on the front of the instrument and manually rotate the turret to the correct position; close the door; and select the [OK] button.

3.8 Bleed off any fuel remaining in the lines by depressing the RED [OFF] button on the instrument front panel until a "click" is heard; keep the button depressed for ~15 to 30 seconds, while the fuel tank pressure gauges drop to zero.

3.9 Ignite the flame. (For acetylene-air flames) Open the air valve (~30 psi); open the main valve on the acetylene tank (the output valve should already be open); if necessary adjust the acetylene output pressure to ~8-10 psi.

If the Ignite button on the spectrometer is flashing, it is safe to ignite the flame. Be sure the safety cover is over the flame box. Depress the ignite button until the flame ignites (a few seconds); if necessary, adjust the fuel flow rate to ~20, or until a desirable flame quality is observed.

3.10 Check the waste bottle. If the waste level is close to the discharge tubing, dispose of the waste before continuing.

3.11 If the lamps have warmed up for a few minutes, check the [SPECTROMETER] window displayed on the screen to see if the proper wavelength has been selected for the element and the absorbance and photomultiplier voltage values are reasonable. After aspirating deionized water (blank) for about 5 seconds, select the [0.0] ICON from the Icon Bar near the top of the screen. This will automatically zero the output absorbance reading. Air can be aspirated into the sample chamber in place of solution between subsequent analyses.

3.12 Go to the specific AA procedure in this manual. For SHUT-DOWN see Section 4.

NOTE: To make any of the parameter windows active, either select the ICON, or select the Top Bar of the displayed Window. The Commands related to this selected parameter will then become available at the Right-Hand Side of the Top Command Bar.

 

 

4. Shut-down

4.1 Remove aspiration tube from solution.

4.2 Turn off flame by depressing Red [OFF] button and holding until flame goes out.

4.3 Turn off the main Acetylene tank valve. Turn off the air valve.

4.4 Bleed off any fuel remaining in the lines by depressing the RED [OFF] button on the instrument front panel until a "click" is heard; keep the button depressed for ~15 to 30 seconds, while the fuel tank pressure gauges drop to zero.

4.5 Exit the operating program by clicking on the [-] box in the upper left-hand corner of the screen; select [Close] from the pop-down menu; continue this selection from each screen that appears until the box appears saying "This will end your Windows session?", to which you respond with [OK].

4.6 Turn off the spectrometer power switch on the lower left of the front panel.

4.7 Turn off the computer, and all power, at the power distribution strip.

4.8 Turn off the Exhaust Fan.