Central European Journal of Chemistry最新文献

{"title":"Ultratrace-level determination of N-Nitrosodimethylamine, N-Nitrosodiethylamine, and N-Nitrosomorpholine in waters by solid-phase extraction followed by liquid chromatography-tandem mass spectrometry","authors":"Y. Kadmi, L. Favier, I. Soutrel, M. Lemasle, D. Wolbert","doi":"10.2478/s11532-014-0537-z","DOIUrl":"https://doi.org/10.2478/s11532-014-0537-z","url":null,"abstract":"N-nitrosamines are a new class of emerging nitrogenous drinking water disinfection by-products. These compounds are probably carcinogenic which could seriously affect the safety of drinking water consumers. The aim of this study is to develop a simple, fast, and specific analytical method for the routine determination of low part per trillion levels of N-nitrosamines in waters. An ultra high pressure liquid chromatography coupled with tandem mass spectrometry (UHPLC/MS/MS) method was developed for the qualitative and quantitative analysis of N-nitrosamines in waters. N-nitrosamines were extracted, purified and concentrated from water samples in one step using a solid-phase extraction (SPE). The compounds were detected in multiple reaction monitoring via electrospray ionisation source with positive ionisation mode. To achieve symmetrical peak shapes and a short chromatographic analysis time, the mobile phase consisting of acetonitrile, water and formic acid (60:40:0.1, v/v/v) was used in the experiment. Chromatographic separation of N-nitrosamines was done in less than two minutes. All calibration curves had good linearity (r2≥ 0.9989). The intra- and inter-day precision of the assay ranged from 0.59% to 3.11% and accuracy ranged from 99.66% to 104.1%. The mean recoveries of N-nitrosamines in spiked water were 98%-101%. The reproducability was acceptable with relative standard deviations of less than 3.53%. The proposed method yielded detection limits very low which ranges from 0.04 to 0.16 ng L−1. Finally, the developed analytical method was successfully applied to the analysis of N-nitrosamines in natural water sample","PeriodicalId":9888,"journal":{"name":"Central European Journal of Chemistry","volume":"18 1","pages":"928-936"},"PeriodicalIF":0.0,"publicationDate":"2014-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"83007352","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Removal of zinc ions as zinc chloride complexes from strongly acidic aqueous solutions by ionic exchange","authors":"Emilia Gîlcă, A. Măicăneanu, P. Ilea","doi":"10.2478/s11532-014-0504-8","DOIUrl":"https://doi.org/10.2478/s11532-014-0504-8","url":null,"abstract":"The aim of this study was to compare several anion exchangers and to investigate the capacity of Amberlite IRA410 to remove zinc as chloride [ZnCl3]− from hydrochloric solutions (1 M). Influence of the process parameters such as stirring rate, resin quantity and zinc initial concentration over the removal process, was considered. The highest experimental ionic exchange capacity between the considered anionic exchangers, in the same working conditions (500 rpm, 5 g resin and 500 mg L−1), was obtained for Amberlite IRA410, 8.34 mg g−1. With an increase of zinc ions concentration, ionic exchange capacity increased up to 19.31 mg g−1 (1100 mg L−1). The experimental data were analysed using Langmuir, Freundlich, Temkin and Dubinin-Radushkevich isotherm models. The results were also analyzed using sorption kinetics models, pseudo-first-, pseudo-second-order, intra-particle and film diffusion models. From the Dubinin-Radushkevich and Temkin isotherm models the mean free energy and heat of sorption were calculated to be 7.45 kJ mol−1, respectively 1×10−4 kJ mol−1, which indicates that zinc sorption is characterized by a physisorption process. Kinetic studies showed that the adsorption followed a pseudo-second-order kinetic model.","PeriodicalId":9888,"journal":{"name":"Central European Journal of Chemistry","volume":"29 1","pages":"821-828"},"PeriodicalIF":0.0,"publicationDate":"2014-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"73545807","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Polyphenols in Coreopsis tinctoria Nutt. fruits and the plant extracts antioxidant capacity evaluation","authors":"C. Zălaru, C. C. Crisan, I. Călinescu, Z. Moldovan, Isabela Tarcomnicu, S. Lițescu, R. Tatia, L. Moldovan, D. Boda, M. Iovu","doi":"10.2478/s11532-014-0539-x","DOIUrl":"https://doi.org/10.2478/s11532-014-0539-x","url":null,"abstract":"The aim of this research was to investigate the chemical composition of Coreopsis tinctoria Nutt. fruits extract, to highlight the potential of ultrasound assisted extraction in the fast preparation of extracts rich in polyphenols using different solvents (55%, 78% and 96% hydrous ethanol) and to evaluate the antioxidant potential of formulated extracts. LC-MS/MS was used to characterize the ethanolic extract from Coreopsis tinctoria Nutt. dried fruits. The extract contains different flavonoids (marein, flavanomarein, quercetagetin-7-O-glucoside, okanin aurone, leptosidin, luteolin, apigenin) and phenolic acids (chlorogenic acid, caffeic acid). Several parameters that could affect extraction efficiency were evaluated. Finally, this study focused on determination of plant extracts total phenolic content and their antioxidant capacity. The experimental results allowed the selection of the optimum operating parameters leading to the highest total polyphenolic content, expressed as gallic acid equivalents, and avoiding the degradation of phenolic compounds (ethanol 55%; extraction temperature 323.15 K, extraction time 30 min, liquid/solid ratio 20/1). A good relationship between total phenolic content and antioxidant capacity was obtained.","PeriodicalId":9888,"journal":{"name":"Central European Journal of Chemistry","volume":"62 1","pages":"858-867"},"PeriodicalIF":0.0,"publicationDate":"2014-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"88840353","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"AlZn based Co and Ni catalysts for the partial oxidation of bioethanol — influence of different synthesis procedures","authors":"H. Ehrich, E. Kraleva","doi":"10.2478/s11532-014-0573-8","DOIUrl":"https://doi.org/10.2478/s11532-014-0573-8","url":null,"abstract":"The catalytic performance of Co and Ni catalysts on AlZn mixed oxide supports depends on the synthesis procedure used for their preparation. For this study CoAlZn and NiAlZn catalysts were prepared by conventional sol-gel synthesis of the mixed oxide and subsequent impregnation of the support with the transition metal (SG = sol gel method) as well as by a single-step method were a gel is formed based on salts of all components using citric acid as chelating agent (CM = citrate method). The structure and morphology of the catalysts were characterized by nitrogen sorption, XRD and TPR measurements. They showed high activity in the partial oxidation of ethanol at 600–750 °C, but their properties depend on the preparation method. The higher performance of the catalysts prepared by the citrate method, where the transition metal is incorporated into the crystal structure of the support during preparation, is based on a change in morphology and structure, resulting in more active sites exposed on the surface. Compared to the Co catalysts, Ni catalysts showed a higher performance. This might be due to the higher reducibility and the smaller Ni particles size, which allows a better interaction with the support in NiAlZn catalysts.","PeriodicalId":9888,"journal":{"name":"Central European Journal of Chemistry","volume":"495 1","pages":"1285-1293"},"PeriodicalIF":0.0,"publicationDate":"2014-06-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"77404309","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Recent progress in the application of glow-discharge electrolysis plasma","authors":"Jie Ren, M. Yao, Wu Yang, Yan Li, Jinzhang Gao","doi":"10.2478/s11532-014-0575-6","DOIUrl":"https://doi.org/10.2478/s11532-014-0575-6","url":null,"abstract":"Non-equilibrium plasma makes it is possible to modify surface chemistry, synthetize polymer materials, and oxidize some organic compounds completely by generation of energetic and chemically active species in gas or liquid phases. Glow-discharge electrolysis plasma (GDEP) has been intensely studied for applications in chemistry and in material, environmental, and biomedical engineering during the last few years because of the very highly active chemical species produced during the glow-discharge electrolysis (GDE) process. A brief review is already available regarding applications of glow-discharge electrolysis plasma technique in chemistry and environmental science during the past decade. For convenience of discussion, some papers from prior years are also cited. The contents of this review are focused on the degradation of persistent pollutants, surface modification of materials, and preparation of functional polymers.","PeriodicalId":9888,"journal":{"name":"Central European Journal of Chemistry","volume":"21 1","pages":"1213-1221"},"PeriodicalIF":0.0,"publicationDate":"2014-06-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"78752910","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Kinetic study of wood pyrolysis in presence of metal halides","authors":"Vladimir A. Beliy, E. Udoratina","doi":"10.2478/s11532-014-0577-4","DOIUrl":"https://doi.org/10.2478/s11532-014-0577-4","url":null,"abstract":"The purpose of this work was to study the kinetics of wood pyrolysis in the presence of inorganic salts, representatives of classes of alkali and alkaline earth metal halides (NaCl, KCl, KBr, CaCl2, BaCl2·2H2O) and Lewis acids (AlCl3·6H2O, FeCl3·6H2O, CuCl2, CuBr2, ZnCl2·1.5H2O, NiCl2·6H2O, SnCl2·2H2O) using TG-DSC. The activity of these catalysts was estimated by the temperature of the beginning of pyrolysis, charcoal yield and kinetic parameters, such as energy of activation and reaction order. Using the Lewis acids as catalysts for pyrolysis leads to a decrease in the temperature of the process beginning and the activation energy. In the presence of other catalysts activation energy does not significantly change. The increase of a seeming reaction order in the presence of Lewis acids possibly is a consequence of complication of the thermodestruction mechanism, with the appearance of new parallel competing stages.","PeriodicalId":9888,"journal":{"name":"Central European Journal of Chemistry","volume":"80 1","pages":"1294-1303"},"PeriodicalIF":0.0,"publicationDate":"2014-06-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"85917349","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Biosorption of toxic metals using freely suspended Microcystis aeruginosa biomass","authors":"P. Rzymski, P. Niedzielski, J. Karczewski, B. Poniedziałek","doi":"10.2478/s11532-014-0576-5","DOIUrl":"https://doi.org/10.2478/s11532-014-0576-5","url":null,"abstract":"This paper describes the potential application of a freely suspended cyanobacterial biomass of Microcystis aeruginosa as a sorption material for toxic metals, cadmium (Cd) and lead (Pb) from aqueous solutions. In order to identify the most suitable conditions for removal of these elements (concentration range: 1–20 mg L−1), the laboratory experiments were carried out during different incubation times (1–48 h) and under various temperatures (10–40°C), pH (5–9) and with or without light irradiance. Competitive biosorption of Cd and Pb was also investigated. We found that M. aeruginosa demonstrates high efficiency in removing both of the studied metals from aqueous solutions. Sorption of Pb occurred, however, more rapidly and effectively, and was less disturbed by changes in physico-chemical conditions. Under pH=7, 25°C and light, the removal rates after 3 h and 6 h of incubation, were 90–100% for Pb and 79.5–100% for Cd, respectively. The co-occurrence of the metals decreased the rate of metal biosorption. Pb was sequestered preferentially over Cd. From the results we conclude that freely suspended M. aeruginosa can constitute a promising low-cost, easy-producible biosorbent material for toxic metals in contaminated wastewater.","PeriodicalId":9888,"journal":{"name":"Central European Journal of Chemistry","volume":"13 1","pages":"1232-1238"},"PeriodicalIF":0.0,"publicationDate":"2014-06-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"84810254","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Voltammetric behavior and quantitative determination of ambazone concentrations in urine and in a pharmaceutical formulation","authors":"S. Smarzewska, Dariusz Guziejewski, M. Skowron, S. Skrzypek, W. Ciesielski","doi":"10.2478/s11532-014-0574-7","DOIUrl":"https://doi.org/10.2478/s11532-014-0574-7","url":null,"abstract":"The use of square wave adsorptive stripping voltammetry (SWAdSV) in conjunction with a cyclic renewable silver amalgam film electrode (Hg(Ag)FE) for the analytical determination of ambazone in urine samples and pharmaceutical formulations is described. A single reduction peak in Britton-Robinson buffer at pH 4.0 was detected at about −1.4 V versus Ag/AgCl. Mechanistic studies have shown that the compound can act as an electrocatalyst. The method was validated. The analytical curve was linear in the concentration range from 1.0×10−9 to 1.0×10−7 mol L−1. The detection and quantification limits were found to be 3.0×10−10 mol L−1 and 1.0×10−9 mol L−1, respectively. The proposed method was successfully applied to ambazone determination in real samples.","PeriodicalId":9888,"journal":{"name":"Central European Journal of Chemistry","volume":"5 1","pages":"1239-1245"},"PeriodicalIF":0.0,"publicationDate":"2014-06-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"77562128","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Editorial preface for the special issue “Catalysis for Renewable Sources: Fuel, Energy, Chemicals”","authors":"V. Yakovlev","doi":"10.2478/S11532-014-0578-3","DOIUrl":"https://doi.org/10.2478/S11532-014-0578-3","url":null,"abstract":"FOR RENEWABLE SOURCES: FUEL, ENERGY, CHEMICALS (CRS-2) was held on July 22-28, 2013 at the old university town Lund, situated in the southern Sweden. The First conference CRS-1 took place in St. Petersburg on 2010, and had a great response as an event which demonstrated a high interest to the highly actual and developing trends in science and technology. The First conference collected about 200 participants from 27 countries all over the world. Among the conference organizers were Missouri University of Science and Technology, USA and Petrobras, Brazil. The selection of CRS-2 venue was based on the intensive development of biochemical technology in Scandinavia and on the opportunity to visit the power plants, as well as the objects on production and of the biological materials, the products of fine and organic synthesis from renewable raw materials in Sweden and other neighboring countries. The Lund University was the co-organizer of the conference; the members of the Chemical Technology faculty of the University actively participated in the scientific program of the CRS-2. The conference was devoted to a discussion of the fundamental approaches to the processes of catalytic processing of plant renewable raw materials. The main objective of this discussion is the solution of the most important and especially actual problems today the complex and deep processing of vegetable raw materials to obtain valuable chemicals and fuels. The use of the renewable resources for energy can not only reduce the growth of consumption of traditional fossil fuels, but also reduce human impacts on the environment, including carbon dioxide emissions. Much attention was paid to the discussion of the pyrolysis, gasification, and fermentation technologies for the production of biofuels. The emphasis was made on catalytic methods to address these issues. CRS-2 conference was attended by about 100 participants from 28 countries. The conference program included seven plenary lectures, five keynote presentations, 38 oral and 30 poster presentations. The Plenary session was opened by a recognized expert in the field of chemical engineering from Sweden, Professor Jan Brandin (Linnaeus University). He presented an overview lecture on the current state of development of the new technologies for energy production from renewable raw materials, processes, deep processing of plant materials in Sweden. Traditionally, much attention was attracted by the lecture of one of Russia’s leading scientists in the field of biotechnology, director of the Institute of Biochemical Physics. NM Emanuel, Professor S.D. Varfolomeev. He spoke about the current approaches to the solution of technological problems waste into energy and fuels. The lecture by Professor Tapio Salmi (Åbo Akademi University, Turku, Finland) was devoted to the application of the principles of chemical engineering for low temperature biomass conversion. Interesting results was showed by Professor Jean Carlos SerranoCentral Eu","PeriodicalId":9888,"journal":{"name":"Central European Journal of Chemistry","volume":"14 1","pages":"1246-1247"},"PeriodicalIF":0.0,"publicationDate":"2014-06-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"85119036","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Geochemical investigation of alluvial sediments: validation of ICP-OES determination of heavy metals. A case study from the Utrata River Valley (central Poland)","authors":"M. Biro, Darja Kavšek, J. Karasiński, P. Szwarczewski, E. Bulska, D. Vončina","doi":"10.2478/s11532-014-0520-8","DOIUrl":"https://doi.org/10.2478/s11532-014-0520-8","url":null,"abstract":"The development and validation of a reliable analytical procedure for the determination of selected metals (Cd, Cr, Cu, Pb, Zn and Mn) in sediments accumulated in the Utrata River (Poland) is described. The aqua regia extraction followed by inductively coupled plasma optical emission spectrometry (ICP-OES) was used for this purpose. The optimized analytical procedure was validated, and adequate quality control actions were implemented in order to provide reliable data. The precision under’ within-laboratory’ reproducibility conditions was estimated from duplicate analysis. Certified reference material (CRM) was used in order to evaluate the accuracy of the results regarding the sewage sludge amended soil CRM 143R. The detection limits for all elements of interest were well-below their content in the investigated sediment samples. The obtained reliable data could be used for assessment of the relationship between human economic activity in the past and the geochemical features of the sediments.","PeriodicalId":9888,"journal":{"name":"Central European Journal of Chemistry","volume":"140 1","pages":"687-699"},"PeriodicalIF":0.0,"publicationDate":"2014-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"77707153","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}