Glossary#

This glossary contains all the variables used in TUCAVOC. The names of the variables correspond to names in Python.

abs_u_cal#

\(u_{\mathrm{calib}}\) [pmol/mol] : Certified uncertainty of the RGM amount fraction

Includes the possible drift of the RGM. Please note that the RGM amount fraction is generally given with an expanded uncertainty having a coverage factor of k=2. The standard uncertainty \(u_{\mathrm{calib}}\) is thus half of the expanded uncertainty.

area_blank#

\(A_{\mathrm{blank}}\) [area] : Possible blank area value determined in zero gas measurements

Calculated in: (5) (6)

In few cases, the blank values obtained in zero gas measurements can be significantly higher than the determined peak areas yielding negative amount fractions according to (1) and (4). Then the zero gas procedure and further potential sources of blank values have to be checked and appropriate uncertainties of the blank values have to be estimated. See also blank_conc_preset .

area_calib#

\(A_{\mathrm{calib}}\) [area] : Peak area of calibration gas measurement

area_sample#

\(A_{\mathrm{sample}}\) [area] : Peak area of sample measurement

blank_conc_preset#

\(\chi _{\mathrm{blank}}\) [pmol/mol] : Blank amount fraction

Amount fraction of the blank. A constant value that can be assigned. TUCAVOC will then retrieve the blank area value using Equations (5) or (6). This helps when the value of the blank is known but was not measured in the sample.

calib_factor#

\(f_{\mathrm{calib}}\) [-] : Calibration Factor

Calculated in: (2)

The calibration factor is useful for simplfying the equations.

carbon_number#

\(C_{\mathrm{num}}\) [-] : Carbon number

Number of C atoms in the molecule

carbon_response_factor#

\(C_{\mathrm{resp}}\) [-] : Carbon Response Factor (CRF)

Calculated in: (3)

conc#

\(\chi _{\mathrm{sample}}\) [pmol/mol] : Concentration or Amount fraction of a substance in a sample

Analogous to conc_sample

conc_calib#

\(\chi _{\mathrm{calib}}\) [pmol/mol] : Certified amount fraction of calibration gas

The amount fraction present in the RGM.

conc_sample#

\(\chi _{\mathrm{sample}}\) [pmol/mol] : Amount fraction of a substance in a sample

Calculated in: (1) (4)

conc_std_blank#

\(\sigma _{\mathrm{blank}}\) [pmol/mol] : standard deviation of the amount fraction of a serie of blank runs

Standard deviation of consecutive blank runs. This works only when blanks are read from data files. If blanks are specified by the user the current implementation assumes uncertainty is 0.

detection_limit#

\(\mathrm{LOD}\) [pmol/mol] : Detection Limit

The detection limit is the lowest amount fraction that can be measured with a given instrument.

effective_carbon_number_contribution#

\(y\) [-] : ECN contribution

The ECN contribution, i.e. 1.0 for carbon in aliphatic and aromatic bonds, 0.95 per C in olefinic bonds, 1.3 in acetylenic bonds (Sternberg et al., 1962).

error_systematic_instrument#

\(u_{\mathrm{instrument}}\) [%] : Systematic Instrument Error

Relative error due to the instrument.

flag#

A Flag value

The flag value attributed. See Flagging.

general_mean_carbon_response_factor#

\(\overline{C}_{\mathrm{resp},\mathrm{general}}\) [-] : General Mean Carbon Response Factor (CRF)

Same as mean_carbon_response_factor but including only substances selected for the general CRF.

group_mean_carbon_response_factor#

\(\overline{C}_{\mathrm{resp},\mathrm{group}}\) [-] : Mean CRF of a group

Same as mean_carbon_response_factor but including only substances from a group.

ignore_n_first_blanks#

Number of starting blank runs to be ignored.

Often the first blank samples have residuals of the substances that were measured just before. This means that the blank area might be larger in the first blank measurements. As this could influence the blank value, this parameter allows to select how many of the starting blank runs should be ignored in the calculation.

mean_carbon_response_factor#

\(\overline{C}_{\mathrm{resp}}\) [-] : Mean carbon response factor

Determined from selected substances in the RGM measurements averaging CRF for those substances.

rel_error_conc_blank#

\(\sigma _{\mathrm{conc}blank}\) [%] : Relative error of the blanks concentration.

Relative error of the blank concentration given by the user. See blank_conc_preset .

sigma_rel_series#

\(\sigma^{\mathrm{rel}}_{\mathrm{series}}\) [%] : relative standard deviation of calibrations

At least 6 individual measurements of target gas orworking standard over the considered interval are recommended. However TUCAVOC will also work with less than that.

u_blank#

\(u\left(\chi _{\mathrm{Blank}}\right)\) [pmol/mol] : Unkonwn. Please implement.

Explained in: Uncertainty of the Blank

u_calibration#

\(u\left(\chi _{\mathrm{Calibration}}\right)\) [pmol/mol] : Standard uncertainty of the calibration.

Explained in: Uncertainty of the Calibration

u_further_instrumental_problems#

\(u\left(\chi _{\mathrm{Further\ Instrumental\ Problems}}\right)\) [pmol/mol] : Standard uncertainty associated a further instrumental problems, such as the systematic instrument error.

Explained in: Uncertainty of the Further Instrumental Problems

u_instrument#

\(u\left(\chi _{\mathrm{Instrument}}\right)\) [pmol/mol] : Combined uncertainty of the instrument, which includes the standard uncertainties of the peak integration, linearity and further instrumental problems.

Explained in: Uncertainty of the Instrument

u_linearity#

\(u\left(\chi _{\mathrm{Linearity}}\right)\) [pmol/mol] : Standard uncertainty of the system linearity.

Explained in: Uncertainty of the Linearity

u_peak_area_integ_calib#

\(\frac{u\left(A_{\mathrm{int,}calib}\right)}{A_{\mathrm{calib}}}\) [%] : Uncertainty from peak integration in the calibration

Standard relative uncertainty of the peak integration in the calibration.

u_peak_area_integ_sample#

\(\frac{u\left(A_{\mathrm{int,}sample}\right)}{A_{\mathrm{sample}}}\) [%] : Uncertainty from peak integration in the measurement

Standard relative uncertainty of the peak integration in the measurement.

u_peak_integration#

\(u\left(\chi _{\mathrm{Peak\ Integration}}\right)\) [pmol/mol] : Combined uncertainty of the peak integration

Explained in: Uncertainty of the Peak Integration

u_precision#

\(u\left(\chi _{\mathrm{Precision}}\right)\) [pmol/mol] : Standard uncertainty due to the precision.

Explained in: Uncertainty linked to the reproducibility of the measurement method (Precision)

u_rel_combined#

\(\frac{u\left(\chi _{\mathrm{sample}}\right)^{2}}{\chi _{\mathrm{sample}}}\) [%] : Relative combined uncertainty of the sample measurement.

The combined uncertainty of the sample measurement divided by the amount fraction of the sample.

u_rel_expanded#

\(2*\frac{u\left(\chi _{\mathrm{sample}}\right)^{2}}{\chi _{\mathrm{sample}}}\) [%] : Relative expanded uncertainty of the sample measurement.

The combined uncertainty of the sample measurement multiplied by the factor coverage (k = 2) and divided by the amount fraction of the sample.

u_sampling#

\(u\left(\chi _{\mathrm{Sampling}}\right)\) [pmol/mol] : Standard uncertainty of the sampling techniques.

Explained in: Uncertainty of the sampling method

u_volume#

\(u\left(\chi _{\mathrm{Volume}}\right)\) [pmol/mol] : Combined uncertainty due to the difference between sampling and calibration volumes.

Explained in: Uncertainty of the Volume

uncertainty_due_to_linearity#

\(u_{\mathrm{linearity}}\) [pmol/mol] : Uncertainty from non-linearity

uncertainty_sampling_volume_accuracy#

\(u_{\mathrm{sampling}}\) [pmol/mol] : Uncertainty from sampling volume accuracy

use_for_general_crf#

Use in the General Mean CRF calculation

Whether the substance should be used to compute the general_mean_carbon_response_factor .

volume_calib#

\(V_{\mathrm{calib}}\) [ml] : Volume of calibration gas samples

volume_sample#

\(V_{\mathrm{sample}}\) [ml] : Volume of measured samples

volume_uncertainty_calib#

\(u\left(V_{\mathrm{calib}}\right)\) [ml] : Uncertainty of the calibration volume

volume_uncertainty_sample#

\(u\left(V_{\mathrm{sample}}\right)\) [ml] : Uncertainty of the measured sample volume