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结构描述符正交化及典型相关分析在饱和醇、醚质谱分类中的应用
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作者 贠栋 梁逸曾 +2 位作者 徐承建 胡黔楠 梁江龙 《应用化学》 CAS CSCD 北大核心 2004年第3期223-226,共4页
对NIST6 2库中所包含的 377种饱和醇醚进行化学模式识别研究 ,基于块变量思想 ,将正交化和典型相关分析的方法应用于几类常见的质谱分类变量以提取分类信息 ,并由此建立最小二乘判别式分类模型。其最优模型的误判率为 1 0 6 % ,而交互... 对NIST6 2库中所包含的 377种饱和醇醚进行化学模式识别研究 ,基于块变量思想 ,将正交化和典型相关分析的方法应用于几类常见的质谱分类变量以提取分类信息 ,并由此建立最小二乘判别式分类模型。其最优模型的误判率为 1 0 6 % ,而交互检验的误判率为 1 36 %。 展开更多
关键词 质谱分类 饱和醇醚 模式识别 质谱分类变量 块变量 典型相关分析
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Trace Metals in Water Samples Taken from Azerbaijan Sector of Caspian Sea 被引量:1
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作者 Famil Yusif Humbatov Majid Mirza Ahmadov Valeh Saleh Balayev Bahruz Allahverdi Suleymanov 《Journal of Chemistry and Chemical Engineering》 2015年第4期288-295,共8页
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
关键词 Heavy metals Caspian Sea ICP-MS polution.
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Study of oxidization of coal–pitch by O_3 被引量:2
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作者 Wang Yaoling Chen Sishun +1 位作者 Ding Mingjie Xu Zhan 《International Journal of Mining Science and Technology》 SCIE EI CSCD 2016年第4期677-681,共5页
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
关键词 Study Coal-pitch Ozone oxidation Depolymerization
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