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Sulfur chemiluminescence

Tooba Hallaj, Mohammad Amjadi, Jamshid L Manzoori, Neda Azizi
We report on a simple and sensitive sulfur and nitrogen co-doped carbon quantum dot (S,N-CQD)-based chemiluminescence (CL) sensor for the determination of indomethacin. S,N-CQDs were prepared by a hydrothermal method and characterized by fluorescence spectra, Fourier transform infrared spectroscopy and transmission electron microscopy. To obtain the best CL system for determination of indomethacin, the reaction of S,N-CQDs with some common oxidants was studied. Among the tested systems, the S,N-CQD-KMnO4 reaction showed the highest sensitivity for the detection of indomethacin...
May 19, 2017: Luminescence: the Journal of Biological and Chemical Luminescence
Victor Abrahamsson, Nenad Ristic, Kristina Franz, Kevin Van Geem
Fouling tendencies of a series of gas condensates were evaluated using comprehensive two-dimensional gas chromatography with flame ionization detection and sulfur chemiluminescence detection. A pixel-based approach was applied in order to identify parts of the chromatograms which were associated with the reactor coil fouling. Particular emphasis is given in this work to evaluate several feature selection methodologies along with various data preprocessing procedures. It was found that both aspects were crucial for studying the fouling tendencies and, as part of the subsequent partial least squares model development, predominantly the feature selection...
April 14, 2017: Journal of Chromatography. A
Hitoshi Kodamatani, Steven J Balogh, Yabing H Nollet, Akito Matsuyama, Vesna Fajon, Milena Horvat, Takashi Tomiyasu
An inter-laboratory study was conducted to compare results from different analytical methods for monomethylmercury (MeHg) concentrations in 17 soil and sediment samples. The samples were collected from mercury-contaminated areas, including Minamata Bay and Kagoshima Bay in Japan, the Idrija mercury mine in Slovenia, and an artisanal small-scale gold mining area in Indonesia. The Hg in these samples comes from several different sources: industrial waste from an acetaldehyde production facility, volcanic activity, Hg mining activity, and artisanal and small-scale gold mining activity (ASGM)...
February 2017: Chemosphere
N Suzuki, M Kōchi, N Wada, S Mashiko, T Nomoto, B Yoda
Reaction rate constants between superoxide (O2(-)) and natural anti-oxidants, amino acids and some related sulfur-containing compounds were determined by quenching the chemiluminescence of a Cypridina luciferin analogue, 2-methyl-6-phenyl-3,7-dihydroimidazo[1,2-a]pyrazin-3-one (CLA) in pH 7.0 buffer solutions at 25°C as described in our previous report. The results are discussed in comparison with the literature data. We found that the present method can be applied to measured antioxidative activity of even a fairly unstable sample...
January 1992: Bioscience, Biotechnology, and Biochemistry
Mohammad Asghar, Mohammad Yaqoob, Nusrat Munawar, Abdul Nabi
Chemiluminescence (CL) with a flow-injection method is reported for the determination of thiabendazole (TBZ) fungicide based on its enhancement effect on diperiodatocuprate(III) (DPC)-sulfuric acid-CL system. The calibration graph was linear in the concentration range of 1 - 2000 μg L(-1) (R(2) = 0.9999, n = 8) with a limit of detection (S/N = 3) of 0.3 μg L(-1). The injection throughput was 160 h(-1) with relative standard deviations (RSD, n = 4) of 1.1 - 2.9% in the concentration range studied. The experimental variables e...
2016: Analytical Sciences: the International Journal of the Japan Society for Analytical Chemistry
Nicole E Heshka, Darcy B Hager
A method for the analysis of dissolved hydrogen sulfide in crude oil samples is demonstrated using gas chromatography. In order to effectively eliminate interferences, a two dimensional column configuration is used, with a Deans switch employed to transfer hydrogen sulfide from the first to the second column (heart-cutting). Liquid crude samples are first separated on a dimethylpolysiloxane column, and light gases are heart-cut and further separated on a bonded porous layer open tubular (PLOT) column that is able to separate hydrogen sulfide from other light sulfur species...
December 10, 2015: Journal of Visualized Experiments: JoVE
Thomas J Bruno, Samuel Allen
One can take advantage of the striking similarity of ignitable liquid vaporization (or weathering) patterns and the separation observed during distillation to predict the composition of residual compounds in fire debris. This is done with the advanced distillation curve (ADC) metrology, which separates a complex fluid by distillation into fractions that are sampled, and for which thermodynamically consistent temperatures are measured at atmospheric pressure. The collected sample fractions can be analyzed by any method that is appropriate...
2013: Journal of Research of the National Institute of Standards and Technology
Nobuo Ochiai, Kikuo Sasamoto, Toru Kishimoto
A method for analysis of hop-derived polyfunctional thiols, such as 4-sulfanyl-4-methylpentan-2-one (4S4M2Pone), 3-sulfanylhexan-1-ol (3SHol), and 3-sulfanylhexyl acetate (3SHA), in beer, hop water extract, and wort at nanogram per liter levels was developed. The method employed stir bar sorptive extraction with in situ derivatization (der-SBSE) using ethyl propiolate (ETP), followed by thermal desorption and gas chromatography-tandem mass spectrometry (TD-GC-MS/MS) with selected reaction monitoring (SRM) mode...
August 5, 2015: Journal of Agricultural and Food Chemistry
Parvez Mahbub, Philip Zakaria, Rosanne Guijt, Mirek Macka, Greg Dicinoski, Michael Breadmore, Pavel N Nesterenko
The applicability of acid degradation of organic peroxides into hydrogen peroxide in a pneumatically driven flow injection system with chemiluminescence reaction with luminol and Cu(2+) as a catalyst (FIA-CL) was investigated for the fast and sensitive detection of organic peroxide explosives (OPEs). The target OPEs included hexamethylene triperoxide diamine (HMTD), triacetone triperoxide (TATP) and methylethyl ketone peroxide (MEKP). Under optimised conditions maximum degradations of 70% and 54% for TATP and HMTD, respectively were achieved at 162 µL min(-1), and 9% degradation for MEKP at 180 µL min(-1)...
October 1, 2015: Talanta
Qun-Lin Zhang, Jun Li, Tao-Tao Ma, Zhong-Tang Zhang
A simple, rapid, and sensitive flow injection method with chemiluminescence detection was developed for the screening of meat samples containing diethylstilbestrol, based on the enhancement by diethylstilbestrol of the cerium(IV)-rhodamine 6G chemiluminescence system in sulfuric acid medium. Under the optimal conditions, the chemiluminescence intensity was linear for the diethylstilbestrol concentration in four types of meat (chicken, beef, mutton, and pork) matrix, with the linear ranges of CL detection more than three orders of magnitude and the detection limits (3σ) in the range 0...
November 15, 2008: Food Chemistry
Xiuhong Meng, Yuan Wang, Linhai Duan, Yucai Qin, Wenguang Yu, Qiang Wang, Shiwei Dong, Yanjun Ruan, Haiyan Wang, Lijuan Song
SBA-15 and Aluminum-substituted SBA-15 with Si/Al molar ratio 10 (Al-SBA-15(10)) mesoporous materials were directly synthesized by a hydrolysis approach and characterized by a powder X-ray diffraction (XRD), N2 physisorption analysis and Fourier transform infrared (FTIR) etc. The relative number of hydroxyl groups was investigated by in situ FTIR systematically. The acid type and acid strength of the adsorbents were monitord by FTIR at 423 K and 673 K, respectively, utilizing pyridine as a probe. Desulfurization performances of the adsorbents were investigated via static adsorption experiment...
September 2014: Journal of Nanoscience and Nanotechnology
Runkun Zhang, Gongke Li, Yufei Hu
To study the interesting chemical reaction phenomenon can greatly contribute to the development of an innovative analytical method. In this paper, a simple CL reaction cell was constructed to study the chemiluminescence (CL) emission from the thermal oxidation of carbon disulfide (CS2). We found that the CL detection of CS2 exhibits unique characteristics of excellent selectivity and rapid response capacity. Experimental investigations together with theoretical calculation were performed to study the mechanism behind the CL reaction...
June 2, 2015: Analytical Chemistry
Bei Wang, Eric C Sivret, Gavin Parcsi, Richard M Stuetz
The management of odorous emissions from sewer networks has become an important issue for sewer operators resulting in the need to better understand the composition of volatile organic sulfur compounds (VOSCs). In order to characterise the composition of such malodorous emissions, a method based on thermal desorption (TD) and gas chromatography coupled to sulfur chemiluminescence detector (GC-SCD) has been developed to determine a broader range of VOSCs, hydrogen sulfide (H2S), methanethiol (MeSH), ethanethiol (EtSH), dimethyl sulfide (DMS), carbon disulfide (CS2), ethylmethyl sulfide (EMS), 1-butanethiol (1-BuSH), dimethyl disulfide (DMDS), diethyl disulfide (DEDS), and dimethyl trisulfide (DMTS)...
May 2015: Talanta
Victor Vitvitsky, Ruma Banerjee
Hydrogen sulfide (H2S) is a metabolite and signaling molecule in biological tissues that regulates many physiological processes. Reliable and sensitive methods for H2S analysis are necessary for a better understanding of H2S biology and for the pharmacological modulation of H2S levels in vivo. In this chapter, we describe the use of gas chromatography coupled to sulfur chemiluminescence detection to measure the rates of H2S production and degradation by tissue homogenates at physiologically relevant concentrations of substrates...
2015: Methods in Enzymology
Ali Mokhtari, Mehrgan Ghazaeian, Mahdieh Maghsoudi, Mohsen Keyvanfard, Iraj Emami
A new method using chemiluminescence (CL) detection has been developed for the simple determination of ketotifen fumarate (KF). The method is based on the catalytic effect of KF in the CL reaction of tris(1,10 phenanthroline)ruthenium(II), Ru(phen)3 (2+), with Ce(IV) in sulfuric acid medium. The CL response was detected using a lab-made chemiluminometer. Effects of chemical variables were investigated and under optimum conditions, the CL intensity was proportional to the concentration of the drug over the range 0...
November 2015: Luminescence: the Journal of Biological and Chemical Luminescence
D W Tapley, G R Buettner, J M Shick
The discovery of symbioses between marine invertebrates and sulfide-oxidizing bacteria at deep-sea hydrothermal vents and in other high-sulfide marine environments has stimulated research into the adaptations of metazoans to potentially toxic concentrations of sulfide. Most of these studies have focused on a particular action of sulfide--its disruption of aerobic metabolism by the inhibition of mitochondrial respiration--and on the adaptations of sulfide-tolerant animals to avoid this toxic effect (1). We propose that sulfidic environments impose another, hitherto over-looked type of toxicity: exposure to free radicals of oxygen, which may be produced during the spontaneous oxidation of sulfide, thus imposing an oxidative stress...
February 1999: Biological Bulletin
Giovanni Valenti, Andrea Fiorani, Simone Di Motta, Giacomo Bergamini, Marc Gingras, Paola Ceroni, Fabrizia Negri, Francesco Paolucci, Massimo Marcaccio
The electrochemistry, photophysics, and electrochemically generated chemiluminescence (ECL) of a family of polysulfurated dendrimers with a pyrene core have been thoroughly investigated and complemented by theoretical calculations. The redox and luminescence properties of dendrimers are dependent on the generation number. From low to higher generation it is both easier to reduce and oxidize them and the emission efficiency increases along the family, with respect to the polysulfurated pyrene core. The analysis of such data evidences that the formation of the singlet excited state by cation-anion annihilation is an energy-deficient process and, thus, the ECL has been justified through the triplet-triplet annihilation pathway...
February 9, 2015: Chemistry: a European Journal
Michael L Downey, Arul Murugan, Sam Bartlett, Andrew S Brown
A novel method for the analysis of total sulphur-containing impurities in a hydrogen matrix has been developed. This method has a limit of detection (LoD) significantly lower than that maximum amount fraction for sulphur-containing compounds (4 nmol mol(-1)) specified by the international standard for hydrogen to be used in fuel cell vehicles (ISO 14687-2). To measure the LoD for this method, a novel gas standard containing five different sulphur-containing compounds at low nmol mol(-1) amount fractions has been gravimetrically prepared...
January 2, 2015: Journal of Chromatography. A
Meng Wang, Suoqi Zhao, Keng H Chung, Chunming Xu, Quan Shi
Detailed characterization of petroleum derived sulfur compounds has been challenging, due to the complex composition of the hydrocarbon matrix. A novel method was developed for selective separation of thiophenic and sulfidic compounds from petroleum. Sulfur compounds were methylated to sulfonium salts by AgBF4 and CH3I, then the polar salts were separated by precipitation from petroleum matrix. The thiophenic and sulfidic sulfonium salts were sequentially demethylated with 7-azaindole and 4-dimethylaminopyridine, obtaining original thiophenic and sulfidic compounds, respectively...
January 20, 2015: Analytical Chemistry
Nicole E Heshka, Darcy B Hager
Two-dimensional heart-cutting gas chromatography is used to analyze dissolved hydrogen sulfide in crude samples. Liquid samples are separated first on an HP-PONA column, and the light sulfur gases are heart-cut to a GasPro column, where hydrogen sulfide is separated from other light sulfur gases and detected with a sulfur chemiluminescence detector. Heart-cutting is accomplished with the use of a Deans switch. Backflushing the columns after hydrogen sulfide detection eliminates any problems caused by high-boiling hydrocarbons in the samples...
December 2014: Journal of Separation Science
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