Search results for "Acetone"
showing 10 items of 350 documents
Determination of aluminum at the parts per billion level by solvent extraction and flame atomic emission spectrometry
1991
A new method for the determination of aluminum at the parts per billion level, by N 2 O/ C 2 H 2 flame emission spectrometry with prior solvent extraction with acetylacetone or 8-hydroxyquinoline in 4-methylpentan-2-one, has been performed. The influence of extraction conditions and instrumental parameters on the sensitivity, precision, and dynamic range of the emission calibration curves have been studied. The limit of detection is between 5 and 10 ppb for both ligands, the variation coefficient being 0.2 and 3% at levels of 75 and 25 ppb, respectively. The method has been applied to the determination of Al in water and the results obtained are compared with those found by the standard add…
Acetone measurements in the exhaled air by the cavity ring-down spectrometry
2020
Our work is focused to develop sensitive optical diagnostic methods for the detection of Volatile Organic Compounds in the breath. For the breath measurements, we have built a cavity ring-down spectrometer, operated in the UV region. The system was tested and calibrated using a KinTek automated permeation tube system with nitrogen as a carrier gas, as well as self- prepared acetone mixtures in air with known concentrations. In this paper, we present results of the measurements of acetone concentration in the breath for the test group of randomly selected 40 people in the age group over 50. We observed the values of acetone concentration in the breath in the range from 0,1 – 80 ppm, with a m…
Direct determination of ethanol and methanol in liquid samples by means of vapor phase-Fourier transform infrared spectroscopy
1997
Abstract A FTIR procedure is proposed for the direct determination of methanol and ethanol in liquid samples, such as alcoholic beverages and eau-de-cologne, based on vapor generation from small injected volumes of untreated samples into a heated Pyrex glass reactor in which, at a temperature of 80°C, ethanol and methanol are volatilized and introduced into a long-path IR gas cell by means of a N2 carrier flow. The IR spectra obtained present two characteristic ethanol bands (1050 and 880 cm−1) and a single characteristic methanol band (1030 cm−1). The measurement of the area of the transient recording obtained for the wavenumber range between 1025–950 and 950–820 cm−1 allows us the determi…
CCDC 770746: Experimental Crystal Structure Determination
2011
Related Article: E.Nauha, A.Ojala, M.Nissinen, H.Saxell|2011|CrystEngComm|13|4956|doi:10.1039/c1ce05077j
The heterodinuclear iron(III) and copper(II) molecule Cu(salen)Fe(acac)2NO3 and its iron precursor Fe(acac)2NO3. Synthesis, magnetic susceptibility, …
1992
Abstract The synthesis, EPR, magnetic and Mossbauer properties of two iron(III) complexes are reported. The heterodinuclear iron(III)-copper(II) complex Cu(salen)Fe(acac)2NO3 is obtained as an adduct from the reaction of the two mononuclear moieties, the Cu(salen) molecule and the mononuclear iron(III) molecule Fe(acac)2NO3 acting as a precursor of the dinuclear unit. The latter molecule itself has been prepared by ligand substitution from the tris-acetylacetonate Fe(acac)3. The dinuclear complex is characterized by comparing the properties of the mono- and the dinuclear complex. Fe(acac)2NO3 is identified from its typical IR spectrum with the main nitrate vibrations at 1380, 1250 and 1010 …
2-(4-Toluidino)pyrimidine
1984
Aus der Kondensation von 4-Tolylguanidin (1) mil den β-Diketonen 2a-g gehen die 2-(4-Toluidino)pyrimidine 3a-g hervor, unter denen sich Vertreter mit antidiabetischer und antimykotischer Wirksamkeit befinden. Antidiabetic Agents, II: 2-(4-Toluidino)pyrimidines Condensations of 4-tolylguanidine (1) with the β-diketones 2a-g yield the 2-(4-toluidino)pyrimidines 3a-g which comprise compounds exhibiting antidiabetic and antimycotic activities.
Antimykotische wirkstoffe. XIX. 4,6-Disubstituierte 2-(cyanamino)pyrimidine
1985
Aus der Umsetzung von Dicyandiamid (1) mit β-Diketonen (2a-c) gehen die 2-Cyanaminopyrimidine (3a-c) hervor. Strukturtyp 3 wird durch spektroskopische Daten gestutzt, wahrend gleichzeitig eine 1-Cyan-2-imino-struktur (4) ausgeschlossen wird. Verbindung 3a zeigt fungistatische und nematizide Wirkungen. The reaction of city dicyandiamide (1) with β-diketones 2a-c leads to 2-(cyanoamino)pyrimidines 3a-c. Structure type 3 is supported by spectroscopic data, while at the same time a 1-cyano-2-imino structure (4) is excluded. Compound 3a exhibits fungistatic and nematicidal activity.
Synthesis, X‐ray Structure, Thermal and Magnetic Behavior of [(bipy) 2 Ni 2 (μ‐Cl) 2 Cl 2 (H 2 O) 2 ]: The First Neutral Ferromagnetically Coupled Si…
2007
NiCl2·6H2O and 2,2′-bipyridine (bipy) (1:1) were allowed to react under ambient conditions in dimethyl sulfoxide in the presence of acetylacetone (Hacac). The resulting green solution was concentrated in vacuo, and a green solid was isolated by precipitation with cold acetone. X-ray quality crystals of [(bipy)2Ni2(μ-Cl)2(Cl)2(H2O)2] (1) were grown by subsequent vapor/liquid diffusion of acetonitrile into a methanolic solution for one week. The structure of 1 consists of a dimeric nickel system with each metal atom in an octahedral geometry. Both equatorial bridging and axial chlorine atoms are present in this neutral species. The nickel–nickel distance (3.441 A) is the shortest reported to …
Electrospinning of α,β-poly(N-2-hydroxyethyl)-dl-aspartamide-graft-polylactic acid to produce a fibrillar scaffold
2010
Abstract α,β-Poly( N -2-hydroxyethyl)- dl -aspartamide grafted with polylactic acid (PHEA- g -PLA) is a biocompatible and biodegradable amphiphilic copolymer that has been already employed to prepare a drug delivery system. In this study we have prepared for the first time a fibrillar scaffold from PHEA- g -PLA by the electrospinning of a solution of this copolymer in a mixture of N , N -dimethyl formamide (DMF) and acetone (80:20 vol/vol). The average diameter and the morphology of electrospun fibers were detected by scanning electron microscopy. Chemical degradation studies in phosphate buffer solution pH 7.4 have been performed until 15 days in order to obtain a preliminary information a…
Stability of nitroaromatic specialty explosives in reversed-phase liquid chromatographic systems
2008
Abstract In this study, the stability of 2,4-dinitroanisole, 2,2′,4,4′,6,6′-hexanitrodiphenylsulfide, 2,3,4,6-tetranitroaniline, 2,4,6-trinitroaniline, 2,4,6-trinitroanisole, and 2,4,6-trinitrochlorobenzene in liquid chromatographic systems was studied under different solvent/eluent conditions. Stock solutions of the explosives were prepared in acetonitrile and diluted with acetone/water, acetonitrile/water, or methanol/water mixtures. Within 48 h, these working solutions were repeatedly injected onto a silica column and eluted with acetonitrile/water or methanol/water mobile phases. Under all conditions, 2,4-dinitroanisole was stable, whereas 2,4,6-trinitroaniline was stable only in the me…