Bleached softwood kraft pulp (BSKP) fibers were pretreated in a 5 mol/L NaOH aqueous solution at 35℃ for 90 min. The ZnCl2/H2O/ C2H5OH was used to treat the pretreated BSKP fibers, filter papers were then prepared. I...Bleached softwood kraft pulp (BSKP) fibers were pretreated in a 5 mol/L NaOH aqueous solution at 35℃ for 90 min. The ZnCl2/H2O/ C2H5OH was used to treat the pretreated BSKP fibers, filter papers were then prepared. In the course of processing, the effects of various molar ratios of ZnCl2/H2O/C2H5OH on the filter paper performance were evaluated. SEMEDX was conducted to analyze the physical configuration of the filter papers. Moreover, FT-IR and XPS were performed to further characterize the BSKP, the pretreated BSKP and the filter paper fibers. The results indicated that the fibers treated by ZnCl2/H2O/C2H5OH were swollen and exhibited slight fibrillation, leading to a looser fiber structure and therefore, enhanced filter paper performance. Air permeability increased from 161.7 L/(m2·s) to 1450.4 L/(m2·s) for the filter papers when the molar ratio of ZnCl2/H2O/C2H5OH was 1:14:1. The optimum molar ratio of ZnCl2/H2O/C2H5OH was found to be 1:14:1, and no significant effect of ZnCl2/H2O/C2H5OH on fibers’ functional groups was detected. These results showed that filtration performance of filter papers was improved when treated with the ZnCl2/H2O/C2H5OH solution.展开更多
CuZnAl catalysts with different La loadings were prepared by a complete liquid phase method and tested for higher alcohols（C_（2＋）OH） synthesis from syngas at the conditions of 250–290 ℃, 4.5 MPa, feed low rate ...CuZnAl catalysts with different La loadings were prepared by a complete liquid phase method and tested for higher alcohols（C_（2＋）OH） synthesis from syngas at the conditions of 250–290 ℃, 4.5 MPa, feed low rate = 150 mL/min and H_2/CO = 2. The catalysts were characterized by XRD, H_2-TPR, NH_3-TPD, N_2 adsorption, XPS, and TEM techniques. Characterization results showed that the incorporation of La into CuZnAl catalysts resulted in the decrease of crystallite size of Cu^0 and a strong interaction among copper and zinc or aluminum oxides. Especially, the incorporation of La increased the amount of weak acid and the Cu content on catalyst surface, which was speculated to contribute the formation of higher alcohols. Among these La-promoted CuZnAl catalysts, the La0.1 catalyst exhibited the best catalytic performance and the selectivity to higher alcohols reached above 60% when the reaction temperature was 290 ℃.展开更多
The configuration of[PdCl_2(C_2H_4OH)]^- has been studied by pseudopotential ab initio method.A cis isomer was found to be the reaction intermediate in the Wacker process.
The electronic structure and chemical bonding of the title comp- lexes have been studied by an unrestricted INDO program made applicable for the lanthanoid compounds.The results indicated:(1)In coordinated bonds O-Ln ...The electronic structure and chemical bonding of the title comp- lexes have been studied by an unrestricted INDO program made applicable for the lanthanoid compounds.The results indicated:(1)In coordinated bonds O-Ln and N-Ln,5d orbitals of Ln have large contribution in all valence orbitals of Ln and 4f orbitals have very small contribution.(2)The covalent chara- cter and ionic character are almost equal in the chemical bond which is comparatively weak between phen,C_2H_5OH and Ln are mainly ionic with some covalent character.展开更多
基金the support of the Natural Science Foundation of Heilongjiang Province (Grant No. C2018007)
文摘Bleached softwood kraft pulp (BSKP) fibers were pretreated in a 5 mol/L NaOH aqueous solution at 35℃ for 90 min. The ZnCl2/H2O/ C2H5OH was used to treat the pretreated BSKP fibers, filter papers were then prepared. In the course of processing, the effects of various molar ratios of ZnCl2/H2O/C2H5OH on the filter paper performance were evaluated. SEMEDX was conducted to analyze the physical configuration of the filter papers. Moreover, FT-IR and XPS were performed to further characterize the BSKP, the pretreated BSKP and the filter paper fibers. The results indicated that the fibers treated by ZnCl2/H2O/C2H5OH were swollen and exhibited slight fibrillation, leading to a looser fiber structure and therefore, enhanced filter paper performance. Air permeability increased from 161.7 L/(m2·s) to 1450.4 L/(m2·s) for the filter papers when the molar ratio of ZnCl2/H2O/C2H5OH was 1:14:1. The optimum molar ratio of ZnCl2/H2O/C2H5OH was found to be 1:14:1, and no significant effect of ZnCl2/H2O/C2H5OH on fibers’ functional groups was detected. These results showed that filtration performance of filter papers was improved when treated with the ZnCl2/H2O/C2H5OH solution.
基金supported by the Key Program of the National Natural Science Foundation of China(No.21336006)the National Key Technology R&D Program(Grant No.2013BAC14B04)the National Natural Science Foundation of China(No.21176167)
文摘CuZnAl catalysts with different La loadings were prepared by a complete liquid phase method and tested for higher alcohols（C_（2＋）OH） synthesis from syngas at the conditions of 250–290 ℃, 4.5 MPa, feed low rate = 150 mL/min and H_2/CO = 2. The catalysts were characterized by XRD, H_2-TPR, NH_3-TPD, N_2 adsorption, XPS, and TEM techniques. Characterization results showed that the incorporation of La into CuZnAl catalysts resulted in the decrease of crystallite size of Cu^0 and a strong interaction among copper and zinc or aluminum oxides. Especially, the incorporation of La increased the amount of weak acid and the Cu content on catalyst surface, which was speculated to contribute the formation of higher alcohols. Among these La-promoted CuZnAl catalysts, the La0.1 catalyst exhibited the best catalytic performance and the selectivity to higher alcohols reached above 60% when the reaction temperature was 290 ℃.
文摘The configuration of[PdCl_2(C_2H_4OH)]^- has been studied by pseudopotential ab initio method.A cis isomer was found to be the reaction intermediate in the Wacker process.
文摘The electronic structure and chemical bonding of the title comp- lexes have been studied by an unrestricted INDO program made applicable for the lanthanoid compounds.The results indicated:(1)In coordinated bonds O-Ln and N-Ln,5d orbitals of Ln have large contribution in all valence orbitals of Ln and 4f orbitals have very small contribution.(2)The covalent chara- cter and ionic character are almost equal in the chemical bond which is comparatively weak between phen,C_2H_5OH and Ln are mainly ionic with some covalent character.
