The binding energy spectrum and electron momentum distributions for the outer valence orbitals of n-propyl iodide molecule have been measured using the electron momentum spectrometer employing non-coplanar asymmetric ...The binding energy spectrum and electron momentum distributions for the outer valence orbitals of n-propyl iodide molecule have been measured using the electron momentum spectrometer employing non-coplanar asymmetric geometry at impact energy of 2.5 keV plus binding energy. The ionization bands have been assigned in detail via the high accuracy SACCI general-R method calculation and the experimental momentum profiles are compared with the theoretical ones calculated by Hartree-Fock and B3LYP/aug-cc-pVTZ(C,H)6-311G??(I). The spin-orbit coupling effect and intramolecular orbital interaction have been analyzed for the outermost two bands, which are assigned to the iodine 5p lone pairs, using NBO method and non-relativistic as well as relativistic calculations. It is found that both of the interactions will lead to the observed differences in electron momentum distributions. The experimental results agree with the relativistic theoretical momentum profiles, indicating that the spin-orbit coupling effect dominates in n-propyl iodide molecule.展开更多
The vapor-liquid equilibrium data of four binary systems (acetic acid +p-xylene, methyl acetate +n-propyl acetate, n-propyl acetate +p-xylene and methyl acetate +p-xylene) are measured at 101.33 kPa with Ellis equilib...The vapor-liquid equilibrium data of four binary systems (acetic acid +p-xylene, methyl acetate +n-propyl acetate, n-propyl acetate +p-xylene and methyl acetate +p-xylene) are measured at 101.33 kPa with Ellis equilibrium still, and then both the NRTL and UNIQUAC models are used in combination with the HOC model for correlating and estimating the vapor-liquid equilibrium of these four binary systems. The estimated binary VLE results using correlated parameters agree well with the measured data except the methyl acetate +p-xylene system which easily causes bumping and liquid rushing out of the sampling tap due to their dramatically different boiling points. The correlation results by NRTL and UNIQUAC models have little difference on the average absolute deviations of temperature and composition of vapor phase, and the results by NRTL model are slightly better than those by UNIQUAC model except for the methyl acetate +n-propyl acetate system, for which the latter gives more accurate correlations.展开更多
A new method was developed for the determination of cefradine by extraction-flotation of CuSCN. The experiment indicated that in the presence of 0.20 mol/L NaOH the degradation of cefradine took place in water bath at...A new method was developed for the determination of cefradine by extraction-flotation of CuSCN. The experiment indicated that in the presence of 0.20 mol/L NaOH the degradation of cefradine took place in water bath at 100 ℃. The thiol group (-SH) of the degradation product could reduce Cu(Ⅱ) to Cu(Ⅰ) for the formation of the emulsion CuSCN in the presence of NH4SCN at pH 4.0. By determining the residual amount of Cu(Ⅱ) in the solution and calculating the flotation yield of Cu(Ⅱ), the indirect determination of cefradine can be obtained. This method has been applied to determine cefradine in capsules, human serum and urine samples, respectively.展开更多
Silica-bonded N-propyl sulfamic acid (SBNPSA) catalyzed one-pot three component Biginelli condensation of different substituted aromatic aldehydes with ethyl acetoacetate and urea/thoiurea to the respective 3,4-dihy...Silica-bonded N-propyl sulfamic acid (SBNPSA) catalyzed one-pot three component Biginelli condensation of different substituted aromatic aldehydes with ethyl acetoacetate and urea/thoiurea to the respective 3,4-dihydropyrimidin-2-(lH)-ones and thiones in environment friendly procedure is described. The facile reaction conditions, simple isolation and purification procedures of this method make it a good option for the svnthesis of dihydropyrimidinones.展开更多
建立并优化了新鲜辣椒中甲氰菊酯、高效氯氟氰菊酯、氯菊酯、氟氯氰菊酯、氯氰菊酯、氰戊菊酯、溴氰菊酯7种拟除虫菊酯类农药残留的气相色谱(GC-μECD)分析方法。采用50 mL V(乙腈)∶V(水)=3∶1的混合溶剂提取,二氯甲烷萃取,N-正丙基乙...建立并优化了新鲜辣椒中甲氰菊酯、高效氯氟氰菊酯、氯菊酯、氟氯氰菊酯、氯氰菊酯、氰戊菊酯、溴氰菊酯7种拟除虫菊酯类农药残留的气相色谱(GC-μECD)分析方法。采用50 mL V(乙腈)∶V(水)=3∶1的混合溶剂提取,二氯甲烷萃取,N-正丙基乙二胺(PSA)净化,HP-1毛细管色谱柱分离,气相色谱-电子捕获检测器(GC-μECD)测定。在添加水平为0.017~0.64 mg/kg下的平均回收率为74.0%~105.6%,相对标准偏差为3.3%~15%。该方法准确、灵敏,可同时测定辣椒中7种拟除虫菊酯类农药的残留量。展开更多
文摘The binding energy spectrum and electron momentum distributions for the outer valence orbitals of n-propyl iodide molecule have been measured using the electron momentum spectrometer employing non-coplanar asymmetric geometry at impact energy of 2.5 keV plus binding energy. The ionization bands have been assigned in detail via the high accuracy SACCI general-R method calculation and the experimental momentum profiles are compared with the theoretical ones calculated by Hartree-Fock and B3LYP/aug-cc-pVTZ(C,H)6-311G??(I). The spin-orbit coupling effect and intramolecular orbital interaction have been analyzed for the outermost two bands, which are assigned to the iodine 5p lone pairs, using NBO method and non-relativistic as well as relativistic calculations. It is found that both of the interactions will lead to the observed differences in electron momentum distributions. The experimental results agree with the relativistic theoretical momentum profiles, indicating that the spin-orbit coupling effect dominates in n-propyl iodide molecule.
基金Supported by the Major State Basic Research Development Program of China (2012CB720500), the National Natural Science Foundation of China (U1162202, 61174118) and the Shanghai Leading Academic Discipline Project (B504).
文摘The vapor-liquid equilibrium data of four binary systems (acetic acid +p-xylene, methyl acetate +n-propyl acetate, n-propyl acetate +p-xylene and methyl acetate +p-xylene) are measured at 101.33 kPa with Ellis equilibrium still, and then both the NRTL and UNIQUAC models are used in combination with the HOC model for correlating and estimating the vapor-liquid equilibrium of these four binary systems. The estimated binary VLE results using correlated parameters agree well with the measured data except the methyl acetate +p-xylene system which easily causes bumping and liquid rushing out of the sampling tap due to their dramatically different boiling points. The correlation results by NRTL and UNIQUAC models have little difference on the average absolute deviations of temperature and composition of vapor phase, and the results by NRTL model are slightly better than those by UNIQUAC model except for the methyl acetate +n-propyl acetate system, for which the latter gives more accurate correlations.
文摘A new method was developed for the determination of cefradine by extraction-flotation of CuSCN. The experiment indicated that in the presence of 0.20 mol/L NaOH the degradation of cefradine took place in water bath at 100 ℃. The thiol group (-SH) of the degradation product could reduce Cu(Ⅱ) to Cu(Ⅰ) for the formation of the emulsion CuSCN in the presence of NH4SCN at pH 4.0. By determining the residual amount of Cu(Ⅱ) in the solution and calculating the flotation yield of Cu(Ⅱ), the indirect determination of cefradine can be obtained. This method has been applied to determine cefradine in capsules, human serum and urine samples, respectively.
基金Madhya Pradesh Council of Science & Technology (MPCOST, Bhopal) for their financial support
文摘Silica-bonded N-propyl sulfamic acid (SBNPSA) catalyzed one-pot three component Biginelli condensation of different substituted aromatic aldehydes with ethyl acetoacetate and urea/thoiurea to the respective 3,4-dihydropyrimidin-2-(lH)-ones and thiones in environment friendly procedure is described. The facile reaction conditions, simple isolation and purification procedures of this method make it a good option for the svnthesis of dihydropyrimidinones.
文摘建立并优化了新鲜辣椒中甲氰菊酯、高效氯氟氰菊酯、氯菊酯、氟氯氰菊酯、氯氰菊酯、氰戊菊酯、溴氰菊酯7种拟除虫菊酯类农药残留的气相色谱(GC-μECD)分析方法。采用50 mL V(乙腈)∶V(水)=3∶1的混合溶剂提取,二氯甲烷萃取,N-正丙基乙二胺(PSA)净化,HP-1毛细管色谱柱分离,气相色谱-电子捕获检测器(GC-μECD)测定。在添加水平为0.017~0.64 mg/kg下的平均回收率为74.0%~105.6%,相对标准偏差为3.3%~15%。该方法准确、灵敏,可同时测定辣椒中7种拟除虫菊酯类农药的残留量。