Journal: Sensors (Basel, Switzerland)

Article Title: Characterizing the Performance of a Compact BTEX GC-PID for Near-Real Time Analysis and Field Deployment

doi: 10.3390/s21062095

Figure Lengend Snippet: Side view of the compact benzene, toluene, ethylbenzene, and xylene isomers (BTEX) compact gas chromatograph with photoionization detector (GC-PID) prototype. The system has an ultra-compact chassis (SRI 110 chassis model) weighing 15 kg with dimensions of 36.8 × 21.6 × 34.3 cm.

Article Snippet: The GC system was developed by SRI Instruments (Torrance, CA, USA) and is based on a simpler version of the commercial SRI BTEX GC-PID-FID with a built-in Method 5030 compliant purge and trap concentrator.

Techniques:

Journal: Sensors (Basel, Switzerland)

Article Title: Characterizing the Performance of a Compact BTEX GC-PID for Near-Real Time Analysis and Field Deployment

doi: 10.3390/s21062095

Figure Lengend Snippet: BTEX GC-PID descriptions for configuration a, b, and c. Configuration a and b had the same capillary columns with different backflushing method, while configuration c retained the precolumn backflushing method with new capillary columns. Only benzene and toluene limit of detections are show for comparison purposes.

Article Snippet: The GC system was developed by SRI Instruments (Torrance, CA, USA) and is based on a simpler version of the commercial SRI BTEX GC-PID-FID with a built-in Method 5030 compliant purge and trap concentrator.

Techniques:

Journal: Sensors (Basel, Switzerland)

Article Title: Characterizing the Performance of a Compact BTEX GC-PID for Near-Real Time Analysis and Field Deployment

doi: 10.3390/s21062095

Figure Lengend Snippet: We evaluate the detection range of the BTEX GC-PID system by measuring a wide range of mixing ratios until an asymptote is reached. The detection linear range (0–500 ppb) is magnified highlighted by the blue box. The R 2 values for linear fits to each compound are all greater than 0.98.

Article Snippet: The GC system was developed by SRI Instruments (Torrance, CA, USA) and is based on a simpler version of the commercial SRI BTEX GC-PID-FID with a built-in Method 5030 compliant purge and trap concentrator.

Techniques:

Journal: Sensors (Basel, Switzerland)

Article Title: Characterizing the Performance of a Compact BTEX GC-PID for Near-Real Time Analysis and Field Deployment

doi: 10.3390/s21062095

Figure Lengend Snippet: BTEX detection limits for each BTEX GC-PID instrument referred to as GC1 and GC2.

Article Snippet: The GC system was developed by SRI Instruments (Torrance, CA, USA) and is based on a simpler version of the commercial SRI BTEX GC-PID-FID with a built-in Method 5030 compliant purge and trap concentrator.

Techniques:

Journal: Sensors (Basel, Switzerland)

Article Title: Characterizing the Performance of a Compact BTEX GC-PID for Near-Real Time Analysis and Field Deployment

doi: 10.3390/s21062095

Figure Lengend Snippet: Regression plots of BTEX compounds from vehicle exhaust measured by the compact GC-PID instrument (blue) and samples collected in canisters (red) followed by analysis in a traditional benchtop GC. Error bars for the GC-PID are errors propagated from the calibration curve and error bars for the canister samples represent 5% precision accuracy from the benchtop GC.

Article Snippet: The GC system was developed by SRI Instruments (Torrance, CA, USA) and is based on a simpler version of the commercial SRI BTEX GC-PID-FID with a built-in Method 5030 compliant purge and trap concentrator.

Techniques:

Journal: Sensors (Basel, Switzerland)

Article Title: Characterizing the Performance of a Compact BTEX GC-PID for Near-Real Time Analysis and Field Deployment

doi: 10.3390/s21062095

Figure Lengend Snippet: Timeseries of BTEX compounds detected by both GC1 and GC2 abroad a mobile platform before rush hour (15:00 to 16:00 PST) and during the afternoon rush hour (16:00 to 20:00 PST). These results show the portability of the compact GC-PID for mobile applications. Error bars represent error propagated from instrument calibration.

Article Snippet: The GC system was developed by SRI Instruments (Torrance, CA, USA) and is based on a simpler version of the commercial SRI BTEX GC-PID-FID with a built-in Method 5030 compliant purge and trap concentrator.

Techniques:

Journal: Sensors (Basel, Switzerland)

Article Title: Characterizing the Performance of a Compact BTEX GC-PID for Near-Real Time Analysis and Field Deployment

doi: 10.3390/s21062095

Figure Lengend Snippet: Sample chromatograms for three different column and flushing configurations with injection of a 1 ppb BTEX standard. Configurations: ( a ) Separation of heavier BTEX compounds is challenging with the selected columns. ( b ) Heavier hydrocarbons are detected; however, the baseline is not stable and separation of heavier BTEX compounds remains challenging. ( c ) There is better separation of the o-xylene; however, separation of ethylbenzene and m,p-xylenes still remains challenging. The baseline shifts when the 10-port solenoid valve rotates, and the precolumn configuration is no longer in series with the analytical column. This causes the column flow to increase and the baseline to shift as seen in ( c ).

Article Snippet: The BTEX GC-PID instruments are equipped with a PID detector (Andrews Glass) that responds to compounds whose ionization potential is below 10.6 eV, this includes aromatics and molecules with double carbons.

Techniques: Injection

Journal: Sensors (Basel, Switzerland)

Article Title: Characterizing the Performance of a Compact BTEX GC-PID for Near-Real Time Analysis and Field Deployment

doi: 10.3390/s21062095

Figure Lengend Snippet: Side view of the compact benzene, toluene, ethylbenzene, and xylene isomers (BTEX) compact gas chromatograph with photoionization detector (GC-PID) prototype. The system has an ultra-compact chassis (SRI 110 chassis model) weighing 15 kg with dimensions of 36.8 × 21.6 × 34.3 cm.

Article Snippet: The BTEX GC-PID instruments are equipped with a PID detector (Andrews Glass) that responds to compounds whose ionization potential is below 10.6 eV, this includes aromatics and molecules with double carbons.

Techniques:

Journal: Sensors (Basel, Switzerland)

Article Title: Characterizing the Performance of a Compact BTEX GC-PID for Near-Real Time Analysis and Field Deployment

doi: 10.3390/s21062095

Figure Lengend Snippet: BTEX GC-PID descriptions for configuration a, b, and c. Configuration a and b had the same capillary columns with different backflushing method, while configuration c retained the precolumn backflushing method with new capillary columns. Only benzene and toluene limit of detections are show for comparison purposes.

Article Snippet: The BTEX GC-PID instruments are equipped with a PID detector (Andrews Glass) that responds to compounds whose ionization potential is below 10.6 eV, this includes aromatics and molecules with double carbons.

Techniques: Comparison

Journal: Sensors (Basel, Switzerland)

Article Title: Characterizing the Performance of a Compact BTEX GC-PID for Near-Real Time Analysis and Field Deployment

doi: 10.3390/s21062095

Figure Lengend Snippet: We evaluate the detection range of the BTEX GC-PID system by measuring a wide range of mixing ratios until an asymptote is reached. The detection linear range (0–500 ppb) is magnified highlighted by the blue box. The R 2 values for linear fits to each compound are all greater than 0.98.

Article Snippet: The BTEX GC-PID instruments are equipped with a PID detector (Andrews Glass) that responds to compounds whose ionization potential is below 10.6 eV, this includes aromatics and molecules with double carbons.

Techniques:

Journal: Sensors (Basel, Switzerland)

Article Title: Characterizing the Performance of a Compact BTEX GC-PID for Near-Real Time Analysis and Field Deployment

doi: 10.3390/s21062095

Figure Lengend Snippet: Linearity of detected signal to sampling volumes of BTEX compounds. Signal becomes saturated past 2 L, particularly evident for benzene. The error bars represent the standard deviation of the mean of triplicates of peak area. Note: error bars do not appear because they are smaller than the size of the symbol.

Article Snippet: The BTEX GC-PID instruments are equipped with a PID detector (Andrews Glass) that responds to compounds whose ionization potential is below 10.6 eV, this includes aromatics and molecules with double carbons.

Techniques: Sampling, Standard Deviation

Journal: Sensors (Basel, Switzerland)

Article Title: Characterizing the Performance of a Compact BTEX GC-PID for Near-Real Time Analysis and Field Deployment

doi: 10.3390/s21062095

Figure Lengend Snippet: Calibration curves for BTEX compounds. SD of slope indicates standard deviation of the slope in the calibration equation. A %SD lower than 20% indicates linearity exists in the calibration curve. N represents the number of points in the curve.

Article Snippet: The BTEX GC-PID instruments are equipped with a PID detector (Andrews Glass) that responds to compounds whose ionization potential is below 10.6 eV, this includes aromatics and molecules with double carbons.

Techniques: Standard Deviation

Journal: Sensors (Basel, Switzerland)

Article Title: Characterizing the Performance of a Compact BTEX GC-PID for Near-Real Time Analysis and Field Deployment

doi: 10.3390/s21062095

Figure Lengend Snippet: Example of calibration curves for BTEX compounds with the time-varying calibration method using sampling volumes: 0.5, 1.0, 1.5 and 2.0 L. The horizontal error bars represent uncertainty from the certified gas standard, while the vertical error bars (smaller than symbol) represent random instrument error. The corresponding R 2 is shown for each BTEX compound.

Article Snippet: The BTEX GC-PID instruments are equipped with a PID detector (Andrews Glass) that responds to compounds whose ionization potential is below 10.6 eV, this includes aromatics and molecules with double carbons.

Techniques: Sampling

Journal: Sensors (Basel, Switzerland)

Article Title: Characterizing the Performance of a Compact BTEX GC-PID for Near-Real Time Analysis and Field Deployment

doi: 10.3390/s21062095

Figure Lengend Snippet: BTEX detection limits for each BTEX GC-PID instrument referred to as GC1 and GC2.

Article Snippet: The BTEX GC-PID instruments are equipped with a PID detector (Andrews Glass) that responds to compounds whose ionization potential is below 10.6 eV, this includes aromatics and molecules with double carbons.

Techniques:

Journal: Sensors (Basel, Switzerland)

Article Title: Characterizing the Performance of a Compact BTEX GC-PID for Near-Real Time Analysis and Field Deployment

doi: 10.3390/s21062095

Figure Lengend Snippet: Drift experiments using a 1 ppb BTEX gas standard organized by date. Observed benzene reported in area units (a.u.). For dates where number of 1 ppb gas standard samples (N) were > 1, the standard deviation is shown in parentheses.

Article Snippet: The BTEX GC-PID instruments are equipped with a PID detector (Andrews Glass) that responds to compounds whose ionization potential is below 10.6 eV, this includes aromatics and molecules with double carbons.

Techniques: Standard Deviation

Journal: Sensors (Basel, Switzerland)

Article Title: Characterizing the Performance of a Compact BTEX GC-PID for Near-Real Time Analysis and Field Deployment

doi: 10.3390/s21062095

Figure Lengend Snippet: BTEX measured concentration of 1 ppb gas standard. Measured pre-rain event relative humidity (RH) was 30–50%, while the post-rain event occurred during the increased relative humidity >50% RH. Error bars represent propagation of uncertainties from gas standard and random instrument error.

Article Snippet: The BTEX GC-PID instruments are equipped with a PID detector (Andrews Glass) that responds to compounds whose ionization potential is below 10.6 eV, this includes aromatics and molecules with double carbons.

Techniques: Concentration Assay

Journal: Sensors (Basel, Switzerland)

Article Title: Characterizing the Performance of a Compact BTEX GC-PID for Near-Real Time Analysis and Field Deployment

doi: 10.3390/s21062095

Figure Lengend Snippet: Regression plots of BTEX compounds from vehicle exhaust measured by the compact GC-PID instrument (blue) and samples collected in canisters (red) followed by analysis in a traditional benchtop GC. Error bars for the GC-PID are errors propagated from the calibration curve and error bars for the canister samples represent 5% precision accuracy from the benchtop GC.

Article Snippet: The BTEX GC-PID instruments are equipped with a PID detector (Andrews Glass) that responds to compounds whose ionization potential is below 10.6 eV, this includes aromatics and molecules with double carbons.

Techniques:

Journal: Sensors (Basel, Switzerland)

Article Title: Characterizing the Performance of a Compact BTEX GC-PID for Near-Real Time Analysis and Field Deployment

doi: 10.3390/s21062095

Figure Lengend Snippet: Timeseries of BTEX compounds detected by both GC1 and GC2 abroad a mobile platform before rush hour (15:00 to 16:00 PST) and during the afternoon rush hour (16:00 to 20:00 PST). These results show the portability of the compact GC-PID for mobile applications. Error bars represent error propagated from instrument calibration.

Article Snippet: The BTEX GC-PID instruments are equipped with a PID detector (Andrews Glass) that responds to compounds whose ionization potential is below 10.6 eV, this includes aromatics and molecules with double carbons.

Techniques: