Mineral oils, classified into two main fractions, namely saturated (MOSH) and aromatic hydrocarbons (MOAH), originate from petroleum. Their determination in food is challenging due to the difficulty of isolating them matrix presence natural interferences, leading low reproducibility results among different laboratories. Therefore, standardized procedures are highly required minimize uncertainty...

Functional iron deficiency (FID) is a state in which there is insufficient iron incorporation into erythroid precursors in the face of apparently adequate body iron stores, as defined by the presence of stainable iron in the bone marrow together with a serum ferritin value within normal limits (Macdougall et al, 1989). In its broadest sense this definition encompasses the partial block in iron ...

This paper describes four recent applications of analytical pyrolysis in environmental science and engineering. In all applications, samples were analyzed in order to provide information about the origin of organic matter or changes to an organic matrix. In the first application, pyrolysis-gas chromatography/mass spectrometry (GC/MS) and pyrolysis-GC/flame ionization detection (FID) were used t...

Flight initiation distance (FID), the distance at which an organism flees from an approaching threat, is an ecological metric of cost-benefit functions of escape decisions. We adapted the FID paradigm to investigate how fast- or slow-attacking "virtual predators" constrain escape decisions. We show that rapid escape decisions rely on "reactive fear" circuits in the periaqueductal gray and midci...

A method based on silica gel chromatography and GC-MS/GC-FID analyses was developed for the quantitation of alkaloidal compounds in imported fire ants, Solenopsis richteri, S. invicta, and their hybrid found in the southern United States. The cis and trans alkaloids from fire ant body extracts were successfully separated by silica gel chromatography, identified by GCMS, and quantitated by GC-FI...

The ionization response of hydrocarbons In a hydrogen-atmosphere flame was compared to that of a normal flame ionization detector used in gas chromatography. Absolute response in the hydrogen-atmosphere flame lonizatlon detector (HAFID) was found to be two orders of magnitude less than that of the normal FID. This reduced response is attributed both to oxidation of hydrocarbons in the precombus...

The essential oil in leaves of Polygonum minus Huds., a local aromatic plant, were identified by a pipeline of gas chromatography (GC) techniques coupled with mass-spectrometry (MS), flame ionization detector (FID) and two dimensional gas chromatography time of flight mass spectrometry (GC x GC-TOF MS). A total of 48 compounds with a good match and high probability values were identified using ...

We present a quantum solution to the electron spin decoherence by a nuclear pair-correlation method for the electron-nuclear spin dynamics under a strong magnetic field and a temperature high for the nuclear spins but low for the electron. The theory incorporates the hyperfine interaction, the intrinsic both direct and indirect nuclear interactions, and the extrinsic nuclear coupling mediated b...

Pulsed NMR is the most convenient and powerful technique for measuring diffusion, when it is applicable. Hahn (1) in a seminal paper laid the foundations of the technique. He showed that for a nuclear spin system that obeyed the Bloch equations (taking small liberties with exact details), a 9O.y T 180, RF pulse sequence produced a free induction decay (FID) and an echo, as pictured in Figure 1....

A very simple, rapid and sensitive dispersive liquid-liquid microextraction (DLLME) followed by gas chromatography and flame ionization detection (GC-FID) was developed for the determination of phenol and carvacrol in honey samples. A mixture of 100 μl dichloromethane (extraction solvent) and 0.5 ml acetonitrile (disperser solvent) was rapidly injected into sample solution. Thereby a cloudy sol...