The present study was conducted to investigate the heavy metal contents (As, Ba, Cd, Co, Cr, Cu, Ga, Mo, Mn, Rb, Pb, Cu, Ni, V, U and Zn) in seawater samples, which were collected at two c (5 and 100 m), from 9 di...The present study was conducted to investigate the heavy metal contents (As, Ba, Cd, Co, Cr, Cu, Ga, Mo, Mn, Rb, Pb, Cu, Ni, V, U and Zn) in seawater samples, which were collected at two c (5 and 100 m), from 9 different sites of Azerbaijan sector of the Caspian Sea. The Agitent 7700x Series ICP-MS (inductively coupled plasma mass spectrometry) with HMI (high matrix introduction) system applied to analysis seawater. It was shown, the average concentrations of elements as Cr, Co, Cu, Mn, Pb and Zn in surface water slightly higher than their concentrations in depth water at 100 m. Practically it is not deference of the Mo, Rb and U average concentrations in surface and 100 m depth column water. There was little variation observed for nickel and vanadium. In contrast the concentrations of As, Ga and Ba in samples taken from 100 m, were significantly higher than the concentration in surface samples. Dependence concentration of elements from water columns depth can be explained in accordance with the geochemical system of classification of dissolved forms of elements in the sea water.展开更多
For the purpose of obtaining small molecular and oxygen-containing aromatic compounds, taking a toluene-extracted coal pitch as the research object, the oxidation of coal-pitch by ozone (03) in formic acid was studi...For the purpose of obtaining small molecular and oxygen-containing aromatic compounds, taking a toluene-extracted coal pitch as the research object, the oxidation of coal-pitch by ozone (03) in formic acid was studied. The coal-pitch sample and the oxidized pitch residue were characterized by elementary analysis and Fourier transform infrared spectroscopy (FTIR), while the small molecular products were analyzed by a gas chromatography-mass spectrometer (GC-MS). The results show that the highest oxygen content of oxidized coal pitch had been acquired at a reaction temperature of 50℃C, an 03 flow rate of 6300 mg/h and a reaction time of 4 h. Quite a lot of hydroxyls and carbonyls were introduced into the structure of the oxidized coal-pitch, while the small molecules produced mainly involve nonpolar aro- matic compounds, aromatic anhydride and quinone compounds. It is speculated that the mechanism is direct electrophilic oxidation in which the molecules of 03 directly attack the aromatic ring at its carbon atoms with high electron density, and then generate hydroxyl or carbonyl until the aromatic ring cracks. This study shows that 03 can make the fused aromatic ring of coal-pitch become oxidized and depoly- merized, and hence the ozonization of coal-pitch can be a potential method for obtaining oxygen- containing aromatic compounds.展开更多
文摘The present study was conducted to investigate the heavy metal contents (As, Ba, Cd, Co, Cr, Cu, Ga, Mo, Mn, Rb, Pb, Cu, Ni, V, U and Zn) in seawater samples, which were collected at two c (5 and 100 m), from 9 different sites of Azerbaijan sector of the Caspian Sea. The Agitent 7700x Series ICP-MS (inductively coupled plasma mass spectrometry) with HMI (high matrix introduction) system applied to analysis seawater. It was shown, the average concentrations of elements as Cr, Co, Cu, Mn, Pb and Zn in surface water slightly higher than their concentrations in depth water at 100 m. Practically it is not deference of the Mo, Rb and U average concentrations in surface and 100 m depth column water. There was little variation observed for nickel and vanadium. In contrast the concentrations of As, Ga and Ba in samples taken from 100 m, were significantly higher than the concentration in surface samples. Dependence concentration of elements from water columns depth can be explained in accordance with the geochemical system of classification of dissolved forms of elements in the sea water.
基金financially supported by the Key Project of Science and Technology of Universities of Henan Province (No.14A530003)the Key Project of Science and Technology of Henan Province (No.152102310090)
文摘For the purpose of obtaining small molecular and oxygen-containing aromatic compounds, taking a toluene-extracted coal pitch as the research object, the oxidation of coal-pitch by ozone (03) in formic acid was studied. The coal-pitch sample and the oxidized pitch residue were characterized by elementary analysis and Fourier transform infrared spectroscopy (FTIR), while the small molecular products were analyzed by a gas chromatography-mass spectrometer (GC-MS). The results show that the highest oxygen content of oxidized coal pitch had been acquired at a reaction temperature of 50℃C, an 03 flow rate of 6300 mg/h and a reaction time of 4 h. Quite a lot of hydroxyls and carbonyls were introduced into the structure of the oxidized coal-pitch, while the small molecules produced mainly involve nonpolar aro- matic compounds, aromatic anhydride and quinone compounds. It is speculated that the mechanism is direct electrophilic oxidation in which the molecules of 03 directly attack the aromatic ring at its carbon atoms with high electron density, and then generate hydroxyl or carbonyl until the aromatic ring cracks. This study shows that 03 can make the fused aromatic ring of coal-pitch become oxidized and depoly- merized, and hence the ozonization of coal-pitch can be a potential method for obtaining oxygen- containing aromatic compounds.