The hexane extract of the flowers of Rheum ribes L. which was collected from north-western Iran,was obtained by Soxhlet apparatus and the essential oil composition was obtained by hydro distillationand analyzed by using GC-GC/MS. The extract from the flowers was characterized by a high amountof unsaturated fatty acids (UFA) (66.0%) and some of long chain hydrocarbon compounds. The maincomponent...

The removal of volatile organic compounds (VOC) in biofilters packed with organic filter beds, such as peat moss (PM) and pine sawdust (PS), frequently presents drawbacks associated to the collapse of internal structures affecting the long-term operation. Poly(ethylene ether carbonate) (PEEC) groups grafted to these organic carriers cross linked with 4,4'-methylenebis(phenylisocyanate) (MDI) pe...

hexane was shaken with 2 ml. of boron trifluoride etherate, BF3 + (C2H6)20 (b.-p. 124-126°), at room temperature. The dark blue complex was decomposed by the addition of 100-200 ml. of 95% methanol, then transferred with water into hexane. The hypophase was discarded and the epiphase washed, dried, adsorbed on a suitable lime-celite column (2:1) and developed with hexane. The respective zones w...

The carcinogenic and chronic toxicity potential of commercial hexane solvent was evaluated in F-344 rats and B6C3F1 mice (50/sex/concentration/species) exposed by inhalation for 6 h/day, 5 days/week for 2 years. Target hexane vapor concentrations were 0, 900, 3000, and 9000 ppm. There were no significant differences in survivorship between control and hexane-exposed groups, and clinical observa...

A sensitive method was developed for determination of n-hexane and cyclohexane in human body fluids by headspace capillary gas chromatography (GC) with cryogenic oven trapping. Whole blood and urine samples containing n-hexane and cyclohexane were heated in a 7.5 mL vial at 70 degrees C for 15 min, and 5 mL of the headspace vapor was drawn into a glass syringe. All vapor was introduced through ...

This paper describes the development of a normal-phase liquid chromatography ultraviolet-diode array detection method for the simultaneous quantification of parthenin and coronopilin in the leaves and flowers of Parthenium hysterophorous. The compounds were analyzed on a Merck Si60 silica column (5 µm, 250 × 4 mm) using an isocratic 15:85 mixture of isopropyl alcohol and hexane. The calibration...

Today, seaweed has become essential to medicine due its ability treat disease-afflicted cells without majorly influencing healthy and tissues. This study included a phytochemical analysis, in vitro antioxidant antidiabetic activity of all the extracts Botryocladia leptopoda. Also, analyse cytotoxicity glucose absorption ethanolic extract B. leptopoda using 3T3 cell line through MTT assay. The e...

Individual tocopherol profile of five Agaricus mushroom species, widely consumed in Portugal, was obtained by a normal-phase high-performance liquid chromatography (NP-HPLC). It was used a simple solid-liquid extraction procedure without saponification step and the chromatographic separation was achieved using a YMC-Pack Polyamine II column using an isocratic elution with hexane/ethyl acetate (...

Chromatographic separation and detection of nonfluorescent molecules were integrated in a nanochannel. Our method, extended-nano chromatography realized high-performance separation using pressure-driven flow in a 100-nm scale nanochannel. A photothermal detector, differential interference contrast thermal lens microscope (DIC-TLM) was employed for detection of nonfluorescent samples. In particu...

The possibility of regulating the retention and selectivity of monoalkyl- and polymethyl-substituted aromatic hydrocarbons in normal-phase high-performance liquid chromatography was investigated by modifying the non-polar (hexane) mobile phase with halide derivatives of hydrocarbons. Dichloromethane, chloroform, carbon tetrachloride and ethyl bromide were employed as modifiers. The decrease in ...