recently, 6-(2-naphthyl)-2, 3-dihydro-as-triazine-3-thione (ndtt) was synthesized in laboratory and used successfully for the spectrophotometric determination of nanogram levels of cu2+ in aqueous solution. this reagent forms a specific red complex with cu2+ ions after the extraction by chloroform at alkaline ph. the absorption of the complex in the uv region (313 nm) is about 8 times as strong...

a simple and rapid microextraction procedure based on dispersive liquid-liquid microextraction (dllme) was developed for determination and speciation of trace amounts of chromium (cr) by flame atomic absorption spectrometry (faas). in the proposed approach, chloroform and methanol were used as extraction and dispersive solvents. a new schiff's base ligand, bis(2-methoxy benzaldehyde) ethylene d...

A simple and cost effective solid-phase microextraction device has been developed. Fused-silica capillaries were etched with ammonium hydrogen difluoride prior to coating with an ionic liquid. For comparison, both a bare fused-silica capillary and one pretreated with a Nafion membrane were coated with the ionic liquid. All three coated capillaries were employed for the head space microextractio...

A liquid/gas membrane bioreactor (L/G MBR) was developed to intensify the dark fermentation process. hollow fiber module used combine biohydrogen production, in situ liquid–gas separation and hydrogen producing bacteria retention a single unit. The L/G MBR seeded once did not require further microbial input, as consistent average yield of 0.97 ± 0.09 mol-H2/added mol-glucose production rate 106...

We have shown marked promotion of both proliferation and neuronal differentiation in pluripotent P19 cells exposed to the green tea amino acid theanine, which is a good substrate for SLC38A1 responsible for glutamine transport. In this study, we evaluated the activity of the mammalian target of rapamycin (mTOR) kinase pathway, which participates in protein translation, cell growth and autophagy...

An integrated process coupling solid-liquid extraction and liquid-membrane preconcentration of vincamine was studied. The effect of the ratios solid phase/extractant volume and extractant volume/liquid membrane volume on the mass transfer rate and efficiency of vincamine removal were estimated. It was found that the transfer rate and removal efficiency of the alkaloid were higher with smaller q...