A simple and rapid method for the determination of lead dioxide in minium by headspace gas chromatographic technique.

This paper demonstrated a simple and rapid approach for the determination of lead dioxide in minium using a headspace gas chromatographic (GC) technique. This new approach was based on the measurement of carbon dioxide from the redox reaction between lead dioxide and oxalic acid in a sealed headspace vial. The obtained results indicated that the new approach had good measurement accuracy (relative errors ≤8.

An efficient headspace gas chromatographic technique for determining humic acid content in fertilizer.

A fast, convenient and commercially available approach for analyzing humic acid content in fertilizer using headspace gas chromatography (HS-GC) is presented in this paper. Humic acid is converted into carbon dioxide based on the oxidation of humic acid in strong acidic medium and can be measured via automatic HS-GC. Conditions for the alkaline extraction and the humic acid oxidation process are also optimized.

A fast and simple headspace gas chromatographic technique for quantitatively analyzing urea in human urine.

A fast and convenient headspace gas chromatographic (HS-GC) approach was described for the estimation of urea in human urine. The HS-GC could detect the generated carbon dioxide derived from the urease-catalyzed hydrolysis of urea. It was found that the hydrolysis of urea catalyzed by urease was completed within 40 min at 35 °C.

Determination of iodate in iodized edible salt based on a headspace gas chromatographic technique.

This paper introduces a convenient approach for determining iodate in iodized salt by headspace gas chromatography (HS-GC). The analytical technique can measure the generated carbon dioxide from the redox reaction between iodate and sodium oxalate in the presence of strong acid. The formed carbon dioxide from this reaction in a closed vial is measured by GC.

Utilizing two detectors in the measurement of trichloroacetic acid in human urine by reaction headspace gas chromatography.

A reaction headspace gas chromatography (HS-GC) technique was investigated for quantitatively analyzing trichloroacetic acid in human urine. This method is based on the decomposition reaction of trichloroacetic acid under high-temperature conditions. The carbon dioxide and chloroform formed from the decomposition reaction can be respectively detected by the thermal conductivity detection HS-GC and flame ionization detection HS-GC.

Measurement of water absorption capacity in wheat flour by a headspace gas chromatographic technique.

The purpose of this work is to introduce a new method for quantitatively analyzing water absorption capacity in wheat flour by a headspace gas chromatographic technique. This headspace gas chromatographic technique was based on measuring the water vapor released from a series of wheat flour samples with different contents of water addition. According to the different trends between the vapor and wheat flour phase before and after the water absorption capacity in wheat flour, a turning point (corresponding to water absorption capacity in wheat flour) can be obtained by fitting the data of the water gas chromatography peak area from different wheat flour samples.

A double sealing technique for increasing the precision of headspace-gas chromatographic analysis.

This paper investigates a new double sealing technique for increasing the precision of the headspace gas chromatographic method. The air leakage problem caused by the high pressure in the headspace vial during the headspace sampling process has a great impact to the measurement precision in the conventional headspace analysis (i.e.

Simple and accurate method for determining dissolved inorganic carbon in environmental water by reaction headspace gas chromatography.

We investigate a simple and accurate method for quantitatively analyzing dissolved inorganic carbon in environmental water by reaction headspace gas chromatography. The neutralization reaction between the inorganic carbon species (i.e.

Efficient quantification of water content in edible oils by headspace gas chromatography with vapour phase calibration.

Background: An automated and accurate headspace gas chromatographic (HS-GC) technique was investigated for rapidly quantifying water content in edible oils. In this method, multiple headspace extraction (MHE) procedures were used to analyse the integrated water content from the edible oil sample. A simple vapour phase calibration technique with an external vapour standard was used to calibrate both the water content in the gas phase and the total weight of water in edible oil sample.

Rapid quantitative detection of glucose content in glucose injection by reaction headspace gas chromatography.

This work investigates an automated technique for rapid detecting the glucose content in glucose injection by reaction headspace gas chromatography (HS-GC). This method is based on the oxidation reaction of glucose in glucose injection with potassium dichromate. The carbon dioxide (CO) formed from the oxidation reaction can be quantitatively detected by GC.

Quantitative analysis of total starch content in wheat flour by reaction headspace gas chromatography.

This paper proposed a new reaction headspace gas chromatographic (HS-GC) method for efficiently quantifying the total starch content in wheat flours. A certain weight of wheat flour was oxidized by potassium dichromate in an acidic condition in a sealed headspace vial. The results show that the starch in wheat flour can be completely transferred to carbon dioxide at the given conditions (at 100 °C for 40 min) and the total starch content in wheat flour sample can be indirectly quantified by detecting the CO formed from the oxidation reaction.

Efficient determination of average valence of manganese in manganese oxides by reaction headspace gas chromatography.

This work investigates a new reaction headspace gas chromatographic (HS-GC) technique for efficient quantifying average valence of manganese (Mn) in manganese oxides. This method is on the basis of the oxidation reaction between manganese oxides and sodium oxalate under the acidic condition. The carbon dioxide (CO) formed from the oxidation reaction can be quantitatively analyzed by headspace gas chromatography.

Quantification of anhydride groups in anhydride-based epoxy hardeners by reaction headspace gas chromatography.

We demonstrate a reaction headspace gas chromatographic method for quantifying anhydride groups in anhydride-based epoxy hardeners. In this method, the conversion process of anhydride groups can be realized by two steps. In the first step, anhydride groups in anhydride-based epoxy hardeners completely reacted with water to form carboxyl groups.