A comprehensive study on essential oils extracted from different Calamintha nepeta (L.) Savi subsp. glandulosa (Req.) Ball samples from Tarquinia (Italy) is reported. In this study, the 24-h steam distillation procedure for essential oil preparation, in terms of different harvesting and extraction times, was applied. The Gas chromatography-mass spectrometry (GC/MS) analysis showed that C. nepet...

Concentration and composition of monoterpenoids in plant tissue affects a variety of environmental and ecological issues such as plant defenses, plant classification, and phytotoxicity. Developing the techniques for extracting and estimating the concentration and composition of monoterpenoids must be speciesspecific because monoterpenoid storage location varies between species. Ashe juniper f,J...

A “wet chemistry” approach for isolation of At from an irradiated bismuth target is described. The approach involves five steps: (1) dissolution of bismuth target in conc. HNO3; (2) removal of the HNO3 by distillation; (3) dissolution of residue in 8 M HCl; (4) extraction of At from 8 M HCl into DIPE; and (5) extraction of At from DIPE into NaOH. Results from 55 “optimized” At isolation runs ga...

Distillation, absorption and extraction belong to the oldest and most mature separation technologies. They require often big columns and are energy intensive. In the chemical processing industry these separations are applied usually for the purification of the products, recycling of solvents or catalysts, etc. and are placed as a last step of a production process, after the chemical reactor(s)....

This paper deals with the analysis of pesticide residues by chromatographic methods in samples of plant origin. Emphasis is put on the isolation and clean-up steps of the sample preparation for GC or LC determination. The problems of the extraction solvent selection and clean-up procedures using different types of adsorption column chromatography or gel permeation chromatography are discussed. ...

Sclareol is a high-value natural product obtained by solid/liquid extraction of clary sage (Salvia sclarea L.) inflorescences. Because processes of excretion and accumulation of this labdane diterpene are unknown, the aim of this work was to gain knowledge on its sites of accumulation in planta. Samples were collected in natura or during different steps of the industrial process of extraction (...

The determination of total volatile bases (TVB) is probably the oldest objective chemical method for assessing the spoilage of fishery pro­ ducts. It was proposed about a century ago and was already published as standard method for the inspection of fish in Germany in the first years of this century (KÖNIG, 1910). This simple method is still widely used. A European Union directive on fish hygie...

69 Unit operations are ubiquitous in any chemical process. One of their main purposes is to achieve separation in order to recycle unconverted reactants or reach product purity specifications. If two phases are brought into intimate contact, a few components migrate from one phase to the other in every stage of the unit. Then, the two phases are separated. When we consider equilibrium-staged se...

Deposition of 226Ra from water on nylon was investigated. Measurements performed for different pH and different radium concentrations in the water gave similar absolute activities deposited on the foil surface. Obtained results were used to estimate the amount of 226Ra plated-out on the nylon scintillator vessel in the solar neutrino experiment BOREXINO during filling of the detector. Another p...