We report on the acid dissociation constants (Ka) of diglycolamic acid-type ligands together with comprehensive data on the extraction performance of N,N-dioctyldiglycolamic acid (DODGAA) for 54 metal ions. The pKa of the diglycolamic acid framework was determined to be 3.54 ± 0.03 in water (0.1 M LiCl, 25°C) by potentiometric titration, indicating that DODGAA is strongly acidic compared with a...

the brønsted acidic ionic liquid ([bmim]hso4) catalyzed three-component synthesis of 2h-indazolo[2,1-b]phthalazine-trione derivatives at room temperature. the integrity of the ionic liquid remains reasonably unchanged when it is separated from the reaction mixture by water extraction, as it can be recycled several times without any loss of activity in each of the title syntheses. the products a...

A method combining ultrasound-assisted emulsification-microextraction (USAEME) with gas chromatography-mass spectrometry (GC-MS) was developed for simultaneous determination of four acidic pharmaceuticals, ibuprofen, naproxen, ketoprofen, and diclofenac, as well as four phenols, 4-octylphenol, 4-n-nonylphenol, bisphenol A, and triclosan in municipal wastewaters. Conditions of extraction and sim...

The time course of chorionic gonadotropin stimulation of nuclear basic and acidic protein biosynthesis, phosphorylation, and acetylation as well as DNA biosynthesis in ovaries of immature rats has been investigated. After injection of radioactive precursor and chorionic gonadotropin into immature rats, ovarian histone fractions Fl, FZal, F2a2, F2b, and F3 were isolated by selective acid extract...

Abstract Spent vanadium catalysts of sulfuric acid production (main elemental composition in wt%: 7.5 V, 9.1 K, 10.2 S, 23.2 Si and 1.4 Fe) can be used as a secondary source vanadium. Extraction was studied using two-step leaching (acidic reductive) spent with further oxidizing solutions. The factors hydrolysis temperature, concentration (H2SO4, Na2SO3) ((NH4)2S2O8) reagents, solid/liquid ratio...

Some aspects of both sample preparation and instrumental techniques for analysis of such acidic drugs as acetylsalicylic acid, ibuprofen, gemfibrozil, fenoprofen, naproxen, ketoprofen, and diclofenac, as well as caffeine in surface water and municipal wastewater have been studied and further developed. Water samples were filtered and target analytes were extracted by solid-phase extraction (SPE...

In recent years, the demand for copper and nickel has risen world-wide due to their use in printed circuit boards, batteries, application in marine alloys (due to excellent resistance to corrosion by seawater), and a wide range applications in day-to-day life (Doebrich, 2009). Increasing demand for these metals is leading to rapid depletion of high-grade resources. Alternative sources, such as ...

high-performance liquid chromatography (hplc) methods employing ultraviolet (uv) detector are not sufficiently sensitive to measure the low plasma concentrations following single oral dose of imipramine. therefore, in the present study a simple, rapid and yet sensitive hplc method with uv detection was developed and validated for quantitation of imipramine in human plasma samples. an efficient ...

In copper heap leaching structures, the ore is leached by an acidic solution. After dissolving the ore mineral, the heap is drained off in the acidic solution using a drainage system (consisting of a network of perforated polyethylene pipes and gravelly drainage layers) and is, then, transferred to the leaching plant for copper extraction where the copper is extracted and the remaining solution...