the present study describes the fragmentation under electron ionization (ei) of gas phase serine and threonine amino acids. ab initio methods were performed to calculate the fragmentation paths and interpret the mass spectra. the six lowest energy conformers of l-serine, l-threonine and l-allo-threonine were obtained with b3lyp, g3mp2 and mp2 methods. the adiabatic and vertical ionization energ...

Kinetics and selected variables (temperature, particle size and time) for extraction of Terminalia Catappa L Kernel Oil (TCKO) were investigated using solvent extraction. Kinetic models studied were: parabolic diffusion, power law, hyperbolic, Elovich and pseudo-second-order. In ascending order, the best-fitted models at the optimum temperature and oil yield were Elovich’s model, hyperbolic...

In order to qualitative and quantitative study on essential oil, obtained from leaf and peel of Citrus aurantium L. cultivated in North of Iran (Sari city) the leaves and fruits were gathered on April and November 2002, respectivelly. Clevenger apparatus was used for hydro-distillation extraction in order to provide the oil of leaf and peel of Citrus aurantium L. The outputs of each essential o...

Fix a prime number l. In this paper we develop the theory of relative pro-l completion of discrete and profinite groups — a natural generalization of the classical notion of pro-l completion — and show that the pro-l completion of the Torelli group does not inject into the relative pro-l completion of the corresponding mapping class group when the genus is at least 2. (See Theorem 1 below.) As ...

The present study describes the fragmentation under electron ionization (EI) of gas phase serine and threonine amino acids. Ab initio methods were performed to calculate the fragmentation paths and interpret the mass spectra. The six lowest energy conformers of L-serine, L-threonine and L-allo-threonine were obtained with B3LYP, G3MP2 and MP2 methods. The adiabatic and vertical ionizat...