The resolved aliphatics were assigned by comparison of retention time using aliphatic standards.
Elution with n-hexane gave the total aliphatic (TAH) fraction (F1) while hexane-dichloromethane (10:90 v/v) yielded the branched aromatic hydrocarbons (F2) and elution with hexane-dichloromethane (50:50 v/v) yielded the aromatic hydrocarbon fraction (ArH) (F3) .
Calibration standards were run at the beginning of each working day before each sample batch to establish the calibration curves for aliphatic mixture.
The method detection limit (MDL) was determined as the concentration of individual aliphatic standard in a sample giving a peak with a signal-to-noise (S/N) and ranged from 0.
The pentane (1 and 2), benzene, ethyl acetate, and methanol eluents represent the fractions containing aliphatics, aromatics, hetero-atom containing (ester), and polar compounds, respectively.
The addition of steam caused some of the organic material that remained in shale during retorting in a nitrogen atmosphere as heavy material by the aromatisation of the oil to produce oils which contain more aromatics and less aliphatics.
This could be a result of the steam reactions which could have caused an increase in the aliphatics degradation (cracking).
The aliphatic material represented by the pentane fractions 1 and 2 showed a decrease from 18.
The principal jet fuel used by the USAF, JP-8, is a mixture of petroleum distillates composed primarily of aliphatic and aromatic HCs in approximately a 6:1 ratio (Pleil et al.
Therefore, we estimated internal doses of aliphatic and aromatic HCs from solvents and fuels in mixed-exhaled breath samples collected from 63 participants.
We analyzed the samples in two batches and quantified aliphatic [C.
We assigned the duplicate, end-of-shift breath sample levels from the 13 participants to the same aliphatic HC and BTEX exposure groups (high/low) approximately 70% of the time, indicating relatively high comparability among samples.
Epoxies cured with these products reportedly have at least double the toughness, flexibility, and thermal-shock resistance obtained with aliphatic amines and polyamides.
Armocure aliphatic polyamines provide flexibility, water resistance, solvent resistance, and low viscosity in casting and coating, and also recommended for laminating.
Broad line of epoxy hardeners and catalysts offered, including aliphatic polyamines, aliphatic and aromatic polyamine adducts, anhydrides and polyamides.