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2002年IEEE国际可靠性物理年会论文集论文摘要(2)——光电子发射光谱的神经网络分类
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《电子产品可靠性与环境试验》 2003年第4期62-62,共1页
关键词 电子发射光谱 神经网络分类 集成电路 噪声
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电子耦合等离子体发射光谱测定彝药草乌中的微量元素 被引量:4
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作者 周林宗 王波 +1 位作者 韦薇 朱光辉 《时珍国医国药》 CAS CSCD 北大核心 2008年第9期2141-2142,共2页
目的测定彝药草乌中的Ca,Mg,P,Cr,Mn,Fe,Zn,Cu,Ni,Pb等多种微量元素含量。方法用混酸溶解样品,稀硝酸酸化定容后用电子耦合等离子体发射光谱(ICP-AES)仪测定。结果彝药草乌中含有丰富的常量及微量元素。结论彝药草乌的药理作用与其含有... 目的测定彝药草乌中的Ca,Mg,P,Cr,Mn,Fe,Zn,Cu,Ni,Pb等多种微量元素含量。方法用混酸溶解样品,稀硝酸酸化定容后用电子耦合等离子体发射光谱(ICP-AES)仪测定。结果彝药草乌中含有丰富的常量及微量元素。结论彝药草乌的药理作用与其含有比例适当的对人体有益的微量元素密切相关。 展开更多
关键词 草乌 微量元素 电子耦合等离子体发射光谱
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二氰基二硫纶·邻菲咯啉-5,6-二酮混配锰(Ⅱ)、铁(Ⅱ)和钴(Ⅱ)配合物的电子光谱 被引量:2
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作者 潘庆才 朱顺清 +2 位作者 李伟 沈红旗 彭正合 《华中师范大学学报(自然科学版)》 CAS CSCD 2006年第4期548-550,共3页
报道了新合成的标题配合物MLL′(L=mnt2-,1,2-二氰基乙烯-1,2-二硫醇离子;L′=phen-5,6-dione,1,10-菲咯啉-5,6-二酮)在二甲基亚砜、二甲基甲酰胺、乙二醇二甲醚、四氢呋喃、乙腈和二氯甲烷中的电子吸收光谱,在二甲基甲酰胺和二甲基亚... 报道了新合成的标题配合物MLL′(L=mnt2-,1,2-二氰基乙烯-1,2-二硫醇离子;L′=phen-5,6-dione,1,10-菲咯啉-5,6-二酮)在二甲基亚砜、二甲基甲酰胺、乙二醇二甲醚、四氢呋喃、乙腈和二氯甲烷中的电子吸收光谱,在二甲基甲酰胺和二甲基亚砜中的电子发射光谱. 展开更多
关键词 二氰基二硫纶 1 10菲咯啉-5 6-二酮 配合物 电子吸收光谱 电子发射光谱
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二氰基二硫纶·5-硝基邻菲啰啉铁(Ⅱ)配合物的电子光谱及理论研究
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作者 甘雄 潘庆才 +3 位作者 黄元乔 沈玉芳 李道聪 彭正合 《化学试剂》 CAS CSCD 北大核心 2007年第8期455-458,476,共5页
报道了标题配合物在几种介质中的电子吸收光谱和发射光谱,用密度泛函理论DFT-B3LYP方法对其气态分子进行几何优化,研究了电子结构和前线分子轨道组成。在此基础用CIS、TD-DFT和ZINDO方法进行激发态计算,给出了理论光谱。研究发现配合物... 报道了标题配合物在几种介质中的电子吸收光谱和发射光谱,用密度泛函理论DFT-B3LYP方法对其气态分子进行几何优化,研究了电子结构和前线分子轨道组成。在此基础用CIS、TD-DFT和ZINDO方法进行激发态计算,给出了理论光谱。研究发现配合物紫外区的吸收带本质上属于配体的π→π*跃迁,可见区400~500nm存在本质上属于配体mnt2-到配体5-NO2-phen的荷移跃迁。 展开更多
关键词 二硫纶和邻菲咯啉铁(Ⅱ)配合物 电子吸收和发射光谱 分子内荷移跃迁
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The Determination of Heavy Metal Elements in Honey by MWD-ICP-AES 被引量:3
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作者 陈文 王湘君 +5 位作者 赵阳 苏利兴 张哲 莫兰发 欧阳敏 黄梁 《Agricultural Science & Technology》 CAS 2014年第6期890-894,共5页
In order to build method for measuring of elements in honey, the contents of Ba, Cu, Pb, Cd, As, Hg, Cr, Mn, Se had been determined by microwave diges- tion (MWD) and actively coupled plasma atomic emission spectrom... In order to build method for measuring of elements in honey, the contents of Ba, Cu, Pb, Cd, As, Hg, Cr, Mn, Se had been determined by microwave diges- tion (MWD) and actively coupled plasma atomic emission spectrometry (ICP-AES). The results show that, the range of heavy metal elements were in the range of 0- 10.0 mg/L, with good linear relationship. In addition, all correlation coefficients kept higher than 0.999, and the recovery rate of ample added with standard solution was in 94.1%-110%. By comparison with the result of chemical experiment, the method was quickly accessible and convenient, widely used in the measurement of elements in honey, with satisfactory results. 展开更多
关键词 HONEY ICP-AES MWD ELEMENT
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The Determination of Heavy Metal Elements in Sipunculs nudus by MWD-ICP-AES 被引量:1
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作者 陈文 王湘君 +5 位作者 赵阳 苏利兴 张哲 莫兰发 欧阳敏 黄梁 《Agricultural Science & Technology》 CAS 2014年第5期724-728,共5页
In order to develop a method for measuring of elements in Sipunculus nudus, the contents of Cu, Pb, Cd, Cr, Mn, As, Hg and Ba were determined by actively coupled plasma atomic emission spectrometry (MWD) and microwa... In order to develop a method for measuring of elements in Sipunculus nudus, the contents of Cu, Pb, Cd, Cr, Mn, As, Hg and Ba were determined by actively coupled plasma atomic emission spectrometry (MWD) and microwave digestion (ICP-AES). The results showed that correlation coefficients al kept higher than 0.999 and the recovery rates of sample added standard solutions were in 98%-114%. The results indicated that the contents of Cu, Pb, Cd, Cr, Mn, As, Hg and Ba were 17.119, 3.781, 0.695, 7.351, 1997.982, 0.620, 0.144, 4.249 mg/kg respectively. The contents of Mn exceeded national limit by hundredfold, Cd sevenfold, Pd fourfold, Cd three-and-a-half-fold, and As onefold. Sipunculs nudus became seriously pol uted. Therefore, it is necessary to formulate robust policies to fol ow closely and pay close attention to coastal areas pol ution around Dongfang City. 展开更多
关键词 Sipunculs nudus ICP-AES MWD Heavy metal ELEMENT
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采用直接测汞仪快速测定煤中痕量汞 被引量:16
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作者 张衡 高建文 +2 位作者 王鑫焱 狄楠楠 康俊 《煤质技术》 2014年第1期17-20,共4页
结合DMA-80直接测汞仪的测定原理为样品燃烧、齐纳管吸附、冷蒸气原子吸收光谱,建立了直接测汞仪快速测定煤中痕量汞的分析方法,探讨了煤炭测定中的样品制备、仪器测定条件及其影响因素。实验结果表明:将直接测汞仪快速测定痕量汞的测... 结合DMA-80直接测汞仪的测定原理为样品燃烧、齐纳管吸附、冷蒸气原子吸收光谱,建立了直接测汞仪快速测定煤中痕量汞的分析方法,探讨了煤炭测定中的样品制备、仪器测定条件及其影响因素。实验结果表明:将直接测汞仪快速测定痕量汞的测定结果与电感耦合等离子体-原子发射光谱法进行比较,两者间无统计学差异,其标准样品测定值与标称值吻合。不同汞含量水平的煤炭样品测定结果相对标准偏差(RSD)不大于3.69%且2次重复性实验结果偏差优于国家检验标准方法,可满足ISO检验标准方法的要求,即直接测汞仪法测定汞具有快速、准确且无需样品预处理和无药品试剂污染等特点,适合煤炭样品中痕量汞的测定。 展开更多
关键词 煤炭 电子耦合等离子体-原子发射光谱 直接测汞法 精密度
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Analysis of Cadmium in Water Extracts from Contaminated Soils with High Arsenic and Iron Concentration Levels 被引量:2
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作者 C. Waterlot G. Bidar C. Pruvot F. Douay 《Journal of Environmental Science and Engineering》 2011年第3期271-280,共10页
Cadmium (Cd) concentrations in the water extracts of ten contaminated soils by arsenic (As) with various iron (Fe) contents were measured using inductively coupled plasma atomic emission spectrometry (ICP-AES)... Cadmium (Cd) concentrations in the water extracts of ten contaminated soils by arsenic (As) with various iron (Fe) contents were measured using inductively coupled plasma atomic emission spectrometry (ICP-AES) and electrothermal atomic absorption spectrometry (ETAAS), Due to the potential spectral interferences of As and Fe in the quantification of Cd, two methods were used for the background compensation. The first method was based on the use of a deuterium lamp (BGCD2 mode). The second one required a Cd hollow cathode lamp pulsated with a current for which the intensity varies in the course of time (BGCSR mode). The results showed that the choices of the analytical technique and the method used for the background compensation depend on the Cd, As and Fe concentrations in the solution and the concentration ratios As/Cd or/and Fe/Cd. In comparison with the ICP-AES and the ETAAS in combination with the BGCD2 mode, it was shown that the high-speed self-reversal method (HSSR) was a more appropriate method to correct As and Fe spectral interferences during the Cd measurements. On the other hand, depending on the Cd concentration, it was established that no significant Fe interference occurred during the Cd determination even if Fe concentration was 50 mg/L, reflecting the efficiency of the HSSR method to overcome the Fe interferences in the determination of Cd concentration by ETAAS without any matrix modifier in water extracts. 展开更多
关键词 ETAAS CADMIUM ARSENIC IRON interference.
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Construction of Inorganic Elemental Fingerprint and Multivariate Statistical Analysis of Marine Traditional Chinese Medicine Meretricis concha from Rushan Bay 被引量:6
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作者 WU Xia ZHENG Kang +2 位作者 ZHAO Fengjia ZHENG Yongjun LI Yantuan 《Journal of Ocean University of China》 SCIE CAS 2014年第4期712-716,共5页
Meretricis concha is a kind of marine traditional Chinese medicine(TCM), and has been commonly used for the treatment of asthma and scald burns. In order to investigate the relationship between the inorganic elemental... Meretricis concha is a kind of marine traditional Chinese medicine(TCM), and has been commonly used for the treatment of asthma and scald burns. In order to investigate the relationship between the inorganic elemental fingerprint and the geographical origin identification of Meretricis concha, the elemental contents of M. concha from five sampling points in Rushan Bay have been determined by means of inductively coupled plasma optical emission spectrometry(ICP-OES). Based on the contents of 14 inorganic elements(Al, As, Cd, Co, Cr, Cu, Fe, Hg, Mn, Mo, Ni, Pb, Se, and Zn), the inorganic elemental fingerprint which well reflects the elemental characteristics was constructed. All the data from the five sampling points were discriminated with accuracy through hierarchical cluster analysis(HCA) and principle component analysis(PCA), indicating that a four-factor model which could explain approximately 80% of the detection data was established, and the elements Al, As, Cd, Cu, Ni and Pb could be viewed as the characteristic elements. This investigation suggests that the inorganic elemental fingerprint combined with multivariate statistical analysis is a promising method for verifying the geographical origin of M. concha, and this strategy should be valuable for the authenticity discrimination of some marine TCM. 展开更多
关键词 Meretricis concha traditional Chinese medicine inorganic elemental fingerprint multivariate statistical analysis Rushan Bay
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Inorganic Elemental Determinations of Marine Traditional Chinese Medicine Meretricis concha from Jiaozhou Bay:The construction of Inorganic Elemental Fingerprint Based on Chemometric Analysis 被引量:5
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作者 SHAO Mingying LI Xuejie +3 位作者 ZHENG Kang JIANG Man YAN Cuiiwe LI Yantuan 《Journal of Ocean University of China》 SCIE CAS 2016年第2期357-362,共6页
The goal of this paper is to explore the relationship between the inorganic elemental fingerprint and the geographical origin identification ofMeretricis concha, which is a commonly used marine traditional Chinese med... The goal of this paper is to explore the relationship between the inorganic elemental fingerprint and the geographical origin identification ofMeretricis concha, which is a commonly used marine traditional Chinese medicine (TCM) for the treatment of asthma and scald bums. For that, the inorganic elemental contents ofMeretricis concha from five sampling points in Jiaozhou Bay have been determined by means of inductively coupled plasma optical emission spectrometry, and the comparative investigations based on the contents of 14 inorganic elements (A1, As, Cd, Co, Cr, Cu, Fe, Hg, Mn, Mo, Ni, Pb, Se and Zn) of the samples from Jiaozhou Bay and the previous reported Rushan Bay were performed. It has been found that the samples from the two bays are ap- proximately classified into two kinds using hierarchical cluster analysis, and a four-factor model based on principle component analysis could explain approximately 75% of the detection data, also linear discriminant analysis can be used to develop a prediction model to distinguish the samples from Jiaozhou Bay and Rushan Bay with accuracy of about 93%. The results of the present investi- gation suggested that the inorganic elemental fingerprint based on the combination of the measured elemental content and chemom- etric analysis is a promising approach for verifying the geographical origin ofMeretricis concha, and this strategy should be valuable for the authenticity discrimination of some marine TCM. 展开更多
关键词 Meretricis concha marine traditional Chinese medicine inorganic elemental fingerprint chemometric analysis
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The Influence of Seafloor Hydrothermal Activity on Major and Trace Elements of the Sediments From the South Mid-Atlantic Ridge 被引量:4
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作者 HUANG Xin CHEN Shuai +2 位作者 ZENG Zhigang PU Xiaoqiang HOU Qinghua 《Journal of Ocean University of China》 SCIE CAS CSCD 2017年第5期775-780,共6页
Sediment samples obtained from the South Mid-Atlantic Ridge were analyzed for the major and trace elements by inductively coupled plasma atomic emission spectroscopy and inductively coupled plasma mass spectrometry. R... Sediment samples obtained from the South Mid-Atlantic Ridge were analyzed for the major and trace elements by inductively coupled plasma atomic emission spectroscopy and inductively coupled plasma mass spectrometry. Results revealed that the contents of elements(e.g., Fe, Mn, Cu, Zn, V, Co) were high in samples 22V-TVG10 and 26V-TVG05 from the sites near the hydrothermal areas, and low in sample 22V-TVG14, which was collected far from the hydrothermal areas. The contents of Ca, Sr and Ba in the samples showed opposite trends. A positive correlation between the concentrations of metallic elements(Cu, Zn, Co, Ni, Pb, V) and Fe in the samples were observed. These results are consistent with chemical evolution of the dispersing hydrothermal plume. 展开更多
关键词 Atlantic hydrothermal inductively metallic Sediment viscosity ocean agate Major opposite
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Preparation and Characterization of High Purity Enriched 10B Boric Acid via Anti-Solvent Recrystallization 被引量:2
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作者 张卫江 刘天雨 徐姣 《Transactions of Tianjin University》 EI CAS 2016年第3期279-283,共5页
Self-made enriched IUB boric acid as raw material was purified by recrystallization. The effects of final crystallization temperature, crystallization time, stirring speed, crystallization frequency and other factors ... Self-made enriched IUB boric acid as raw material was purified by recrystallization. The effects of final crystallization temperature, crystallization time, stirring speed, crystallization frequency and other factors on the purity were investigated. The appropriate operating condition was that the final crystallization temperature and time were 5 ℃ and 10 h respectively under a low-speed stirring for crystallizing twice, which would make the purity and yield of boric acid reach 99.94% and 95.36%, respectively. Taking this as foundation, recrystallization process was optimized with acetone as anti-solvent, whose amount was the most important index. The boric acid solution was added into acetone and recrystallized under the same condition, and the purity and yield of boric acid would reach 99.98% and 99.61%, respectively. The product detected by XRD was confirmed as boric acid crystal. Main ion concentration in the product was detected by ICP, which basically met the national standard of high purity. Crystal morphology of boric acid was observed by SEM. 展开更多
关键词 anti-solvent recrystallization boric acid PURIFICATION CHARACTERIZATION
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微波消解-ICP-OES法测定化妆品中硒含量 被引量:1
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作者 陈文亮 陈晓燕 郑红林 《广东化工》 CAS 2016年第24期139-140,共2页
建立了化妆品的微波消解方法,并采用电感耦合等离子体发射光谱法(ICP-OES)测定了硒的含量。实验结果表明,采用7.0 mL硝酸和1.0 mL双氧水的混合酸,通过程序升温,并在220℃下进行消解,可使样品完全分解,得到精密度较好的分析结果,得出... 建立了化妆品的微波消解方法,并采用电感耦合等离子体发射光谱法(ICP-OES)测定了硒的含量。实验结果表明,采用7.0 mL硝酸和1.0 mL双氧水的混合酸,通过程序升温,并在220℃下进行消解,可使样品完全分解,得到精密度较好的分析结果,得出方法的线性范围0.10~10.0 mg/L,相关系数为0.9998,回收率为92.5%~103.6%,RSD值为0.98%~2.53%。该方法样品用量少,溶样周期短,测试速度快,适用于化妆品中硒含量的快速测定。 展开更多
关键词 微波消解 电子耦合等离子体原子发射光谱 总硒
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Distribution,fractionation,and contamination assessment of heavy metals in offshore surface sediments from western Xiamen Bay,China 被引量:2
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作者 Qiuli Yang Gongren Hu +2 位作者 Ruilian Yu Haixing He Chengqi Lin 《Acta Geochimica》 EI CAS CSCD 2016年第4期355-367,共13页
Surface sediment samples were collected at 21 offshore sites in western Xiamen Bay, Southeast China. Total concentrations of Li, V, Cr, Co, Ni, Cu, Zn, St, Mn, Pb, Ba, Fe, and Ti were determined by inductively coupled... Surface sediment samples were collected at 21 offshore sites in western Xiamen Bay, Southeast China. Total concentrations of Li, V, Cr, Co, Ni, Cu, Zn, St, Mn, Pb, Ba, Fe, and Ti were determined by inductively coupled plasma-optical emission spectrometry; Hg was determined by atomic fluorescence spectrometry. A modified BCR sequential extraction procedure was used to extract fractions of the above elements. Concentrations of Pb, Cr, and Hg at most sites met the primary standard criteria of Marine Sediment Quality except site S12 for Pb and S7 for Cr, while concentrations of Zn at 17 sites and Cu at seven sites exceeded the criteria. The mean concentration of Hg was three times higher than the background, with a possible source being the Jiulong River. Fe, Ti, Ba, Co, V, and Li dominated the residual phase, mainly from terrestrial input. Ni, Cr, Pb, and Hg in the non-residual phase varied largely between sites. Sr, Mn, Cu, and Zn were mainly in the non- residual fraction. Most sites showed considerable ecological risk; exceptions were site S7 (very high) and sites S10, S11, and S14 (moderate). Cu showed moderate-to-high pollution and Pb exhibited no-to-low pollution, while other metals had a non-pollution status according to their ratios of secondary phase to primary phase (RSP). Results of two assessment methods showed moderate pollution and a very high ecological risk for Cu, Zn, Ni, and Cr at site S7, which might be due to the local sewage treatment plant. 展开更多
关键词 Heavy metal Fractionation - Assessment Sediments DISTRIBUTION Western Xiamen Bay
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E-pH diagram of ZnS-H_2O system during high pressure leaching of zinc sulfide 被引量:3
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作者 牟望重 张廷安 +5 位作者 刘燕 古岩 豆志河 吕国志 鲍丽 张伟光 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2010年第10期2012-2019,共8页
The values of GΘ,EΘ or pH from 110 to 160℃ were calculated and the relevant potential expressions were obtained.E-pH diagrams of ZnS-H2O system at oxygen partial pressure of 0.8 MPa,ionic activity of 1.0 and differ... The values of GΘ,EΘ or pH from 110 to 160℃ were calculated and the relevant potential expressions were obtained.E-pH diagrams of ZnS-H2O system at oxygen partial pressure of 0.8 MPa,ionic activity of 1.0 and different temperatures were drawn through thermodynamical calculation.With the temperature increasing,the stable regions of S and Zn(Ⅱ) in the E-pH diagrams become gradually larger,but the amplification decreases over 150℃.The impacts of leaching parameters,such as temperature,liquid to solid ratio,initial acidic concentration,leaching time,oxygen partial pressure and stirring speed on the leaching rate of Zn(Ⅱ) and conversion rate of S in the single factor of high pressure leaching experiment of ZnS in autoclave,were studied.The leaching residue was examined by X-ray fluorescence(XRF) chemical composition identification and X-ray diffraction(XRD) phase identification,and the content of the leaching solution was tested by inductively coupled plasma-atomic emission spectrometry(ICP).The experimental results indicate that the leaching rate of zinc increases from 60.05% to 97.85% and the conversion rate of sulfur increases from 38.90% to 80.92% with the temperature increasing from 110℃ to 150℃,5:1 of liquid-to-solid ratio,150 g/L of initial acidic concentration,120 min of leaching time,0.8 MPa of oxygen partial pressure,and 480 r/min of stirring speed,which tend to be stable over 150℃.The experimental results correspond with theoretical calculation. 展开更多
关键词 zinc sulfide high pressure leaching ZnS-H2O system E-pH diagram
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Effect and mechanism of dolomite with different size fractions on hematite flotation using sodium oleate as collector 被引量:7
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作者 罗溪梅 印万忠 +3 位作者 王云帆 孙传尧 马英强 刘建 《Journal of Central South University》 SCIE EI CAS CSCD 2016年第3期529-534,共6页
The effect of dolomite with different particle size fractions on hematite flotation was studied using sodium oleate as collector at p H of about 9. The effect mechanism of dolomite on hematite flotation was investigat... The effect of dolomite with different particle size fractions on hematite flotation was studied using sodium oleate as collector at p H of about 9. The effect mechanism of dolomite on hematite flotation was investigated by means of solution chemistry, ultraviolet spectrophotometry(UV), inductively coupled plasma atomic emission spectrometry(ICP-AES) and X-ray photoelectron spectroscopy(XPS). It is observed that dolomite with different size fractions has depressing effect on hematite flotation using sodium oleate as collector, and dolomite could be the "mineral depressant" of hematite using sodium oleate as collector. The reasons for that are concerned with sodium oleate consumption and the adsorption onto hematite of dissolved species of dolomite. 展开更多
关键词 DOLOMITE HEMATITE sodium oleate mineral dissolution depressing effect
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Design Near-threshold Photoelectron Imaging Spectrometer Based on UV Laser Induced Photoelectron Emission Anion Source
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作者 Zheng-bo Qin Xia Wu Zi-chao Tang 《Chinese Journal of Chemical Physics》 SCIE CAS CSCD 2013年第6期774-779,I0005,共7页
We have developed a compact photoelectron imaging facility, including an anion source with dissociative photoelectron attachment to molecules, a linear time-of-flight mass spec-trometry (TOFMS), and an orthogonal hi... We have developed a compact photoelectron imaging facility, including an anion source with dissociative photoelectron attachment to molecules, a linear time-of-flight mass spec-trometry (TOFMS), and an orthogonal high-resolution threshold photoelectron velocity map imaging spectrometer (VMI). Intense and cold cluster anions were prepared in photoelectron- attachment processes upon pulsed UV laser ablation of metal target. Combining this anion source with TOFMS-VMI, the achieved mass resolution is about 200, and the electron ki- netic energy resolution is better than 3%, i.e., 30 meV for 1 eV electrons. More importantly, low-energy photoelectron imaging spectra for CH3S- and S2- at 611.46 nm are obtained. In both cases, the refined electron affinities are determined to be 1.86264-0.0020 eV for CH3S and 1.67444-0.0035 eV for S2, respectively. Preliminary results suggest that the apparatus is a powerful tool for estimating precise electron affinities values from threshold photoelectron imaging spectroscopy. 展开更多
关键词 Threshold photoelectron imaging Dissociative photoelectron attachment Laser induced photoelectron emission
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Ghezeljeh nanoclay as a new natural adsorbent for the removal of copper and mercury ions: Equilibrium, kinetics and thermodynamics studies 被引量:1
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作者 Majid Soleimani Zahra Hassanzadeh Siahpoosh 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2015年第11期1819-1833,共15页
Heavy metal determination was carried out by applying the solid phase extraction (SPE) method in batch mode followed by atomic absorption spectroscopy (AAS) and inductively coupled plasma atomic emission spectrosc... Heavy metal determination was carried out by applying the solid phase extraction (SPE) method in batch mode followed by atomic absorption spectroscopy (AAS) and inductively coupled plasma atomic emission spectrosco py (ICP-AES) from aqueous solutions using Ghezeljeh montmorillonite nanoclay as a new natural adsorbent. The Ghezeljeh clay is characterized by using Fourier Transform Infrared (FT-IR) Spectroscopy, Scanning Electron Mi- croscopy-Energy Dispersive Spectrometry (SEM-EDS) and X-ray Diffractometry (XRD) and X-ray Fluorescence (XRF). The results of XRD and FT-IR of nanoclay confirm that montmorillonite is the dominant mineral phase. Based on SEM images of Ghezeljeh clay, it can be seen that the distance between the plates is Nano. The effects of varying parameters such as initial concentration of metal ions, pH and type of buffer solutions, amount of ad- sorbent, contact time, and temperature on the adsorption process were examined. The effect of various interfer- ing ions was studied. The adsorption data correlated with Freundlich, Langmuir, Dubinin-Radushkevich (D-R), and Temkin isotherms. The Langmuir and Freundlich isotherms showed the best fit to the equilibrium data for Hg(II), but the equilibrium nature of Cu(ll) adsorption has been described by the Langmuir isotherm. The kinetic data were described with pseudo-first-order, pseudo-second-order and double-exponential models, The adsorp- tion process follows a pseudo-second-order reaction scheme, Calculation of AGσ, △Hσ and ASσ showed that tilenature of Hg(II) ion sorption onto the Ghezeljeh nanoclay was endothermic and was favored at higher temper- attire, and the nature of Cu(II) ion sorption was exothermic and was favored at lower temperature, 展开更多
关键词 Montmorillonite Thermodynamic Kinetic Mercury Copper
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Enhancing Effect of Fe^(2+) on the Formaldehyde Production from Trimethylamine N-oxide Decomposition Catalyzed by the Extract of Harpadon nehereus Kidney 被引量:2
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作者 SUN Yong ZHOU Deqing ZHAO Feng 《Journal of Ocean University of China》 SCIE CAS 2011年第1期67-72,共6页
The effects of Fe2+ on the trimethylamine N-oxide (TMAO) demethylating activity of the Harpadon nehereus kidney extract were studied in this research.The activity of the kidney extract was presumably inhibited by ethy... The effects of Fe2+ on the trimethylamine N-oxide (TMAO) demethylating activity of the Harpadon nehereus kidney extract were studied in this research.The activity of the kidney extract was presumably inhibited by ethylene diamine tetra-acetic acid (EDTA),which indicates that the kidney extract contains an enzyme or enzyme system with metal cations as activator.Activity of the kidney extract was enhanced significantly when Fe2+ was added into the model system in vitro.As the concentration of Fe2+ increased,the decomposing rate of TMAO increased rapidly until TMAO decomposed completely.The activity of the kidney extract was also enhanced by reductant such as ascorbic acid.Inductively Coupled Plasma-Atomic Emission Spectrometry (ICP-AES) was employed to determine the content of total iron in a number of fishery products.Significant positive correlation between the contents of total iron and endogenous formaldehyde (FA) was found,especially in marine products. 展开更多
关键词 TMAOase FORMALDEHYDE mechanism Fe2+ Harpadon nehereus
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Preparation and Characterization of Tungsten-substituted Molybdophosphoric Acids and Catalytic Cyclodehydration of 1,4-Butanediol to Tetrahydrofuran 被引量:5
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作者 吴慧雄 周梅 +2 位作者 屈一新 李海霞 殷恒波 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2009年第2期200-206,共7页
A series of tungsten-substituted molybdophosphoric acids(H3PMo12-nWnO40·xH2O) were synthesized and characterized by inductive coupled plasma atomic emission spectroscopy(ICPAES),thermal gravimetry and differentia... A series of tungsten-substituted molybdophosphoric acids(H3PMo12-nWnO40·xH2O) were synthesized and characterized by inductive coupled plasma atomic emission spectroscopy(ICPAES),thermal gravimetry and differential scanning calorimetry(TG-DSC),Fourier transform infrared spectroscopy(FTIR),X-ray diffraction(XRD),and FTIR pyridine adsorption.The as-prepared heteropoly acids have a Keggin type structure.The synthesis of tetrahydrofuran by reactive distillation and cyclodehydration of 1,4-butanediol was studied using the tungsten-substituted molybdophosphoric acids as catalysts.The results of catalytic test indicated that the catalytic activity increased with the increase in the substitution number(n) of tungsten atom in H3PMo12-nWnO40·xH2O and was constant as the substitution number(n) was more than 8.The catalytic activity increased with the increase in the catalyst loading and the selectivity of tetrahydrofuran was nearly 100%. 展开更多
关键词 tungsten-substituted molybdophosphoric acid 1 4-butanediol TETRAHYDROFURAN reactive distillation
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