We evaluated whether the dodecylamine derivative of hydroxocobalamin acts as a potent inhibitor of cobalamin-dependent enzymes in an African green monkey kidney cell, COS-7. When the dodecylamine derivative (1.0 μmol...We evaluated whether the dodecylamine derivative of hydroxocobalamin acts as a potent inhibitor of cobalamin-dependent enzymes in an African green monkey kidney cell, COS-7. When the dodecylamine derivative (1.0 μmol/L) did not show any cytotoxicity in the cultured cells, the derivative could not affect methylmalonyl-CoA mutase (holo-enzyme) activity, but significantly inhibit methionine synthase (holo-enzyme) activity in the cell homogenates of COS-7 grown in 1.0 μmol/L hydroxocobalamin-supplemented medium. An immunoblot analysis indicated that the dodecylamine derivative could not decrease the protein level of methionine synthase, but significantly inhibit the enzyme activity.展开更多
The core-shell structures of ZSM-5 coated with mesoporous silica were synthesized by means of dodecylamine（DDA） surfactant. The results show that the mesoporous silica shells are coated on ZSM-5 cores and result in ...The core-shell structures of ZSM-5 coated with mesoporous silica were synthesized by means of dodecylamine（DDA） surfactant. The results show that the mesoporous silica shells are coated on ZSM-5 cores and result in the formation of hierarchical porous structures. The thickness of the coating shell can be controlled by changing the adding amount of TEOS. The core-shell composites with the thickness of 35 nm possess high surface areas（about 528 m2·g-1）, large pores（about 3.5 nm in diameter） on the silica shells. The composite molecular sieves display higher adsorption capacity for benzene（140.2 mg·g-1） and butyraldehyde（213.7 mg·g-1） than that of pristine ZSM-5 for benzene（99.2 mg·g-1） and butyraldehyde（134.7 mg·g-1）. The composite molecular sieves show a wide application foreground for harmful gas adsorbent for environmental protection.展开更多
The floatation of the minerals diaspore and kaolinite was investigated using dodecylamine as the collector.Separating diaspore and kaolinite in a neutral pH pulp is difficult since they then have similar floatability....The floatation of the minerals diaspore and kaolinite was investigated using dodecylamine as the collector.Separating diaspore and kaolinite in a neutral pH pulp is difficult since they then have similar floatability.A depressor consisting of an AlCl3/Na2SiO3 mixture is demonstrated to solve this problem.Diaspore sinking may be seen when the ratio of AlCl3 to Na2SiO3 is 3:1.We refer to this mixture as ATNO.The influence of Al/Si ratio in the feedstock and the grain size of fed minerals on separation was examined.An Al/Si ratio in the concentrate greater than 11 may be obtained when the Al/Si ratio of the feed is between 2.53 and 4.96.However,the grain size of the diaspore greatly influences the concentrate grade.Finer grain size of the diaspore(<40 μm) in pulp makes the flotation separation less than ideal,no matter what the kaolinite grain size.展开更多
文摘We evaluated whether the dodecylamine derivative of hydroxocobalamin acts as a potent inhibitor of cobalamin-dependent enzymes in an African green monkey kidney cell, COS-7. When the dodecylamine derivative (1.0 μmol/L) did not show any cytotoxicity in the cultured cells, the derivative could not affect methylmalonyl-CoA mutase (holo-enzyme) activity, but significantly inhibit methionine synthase (holo-enzyme) activity in the cell homogenates of COS-7 grown in 1.0 μmol/L hydroxocobalamin-supplemented medium. An immunoblot analysis indicated that the dodecylamine derivative could not decrease the protein level of methionine synthase, but significantly inhibit the enzyme activity.
基金Funded by the China National Tobacco Corporation(110201101027(JH-02))
文摘The core-shell structures of ZSM-5 coated with mesoporous silica were synthesized by means of dodecylamine（DDA） surfactant. The results show that the mesoporous silica shells are coated on ZSM-5 cores and result in the formation of hierarchical porous structures. The thickness of the coating shell can be controlled by changing the adding amount of TEOS. The core-shell composites with the thickness of 35 nm possess high surface areas（about 528 m2·g-1）, large pores（about 3.5 nm in diameter） on the silica shells. The composite molecular sieves display higher adsorption capacity for benzene（140.2 mg·g-1） and butyraldehyde（213.7 mg·g-1） than that of pristine ZSM-5 for benzene（99.2 mg·g-1） and butyraldehyde（134.7 mg·g-1）. The composite molecular sieves show a wide application foreground for harmful gas adsorbent for environmental protection.
基金support for this study obtained from the Funding Project for Academic Human Resources Development in Institutions of Higher Learning under the Jurisdiction of Beijing Municipality (No.PHR 200906210)Funding Project for Base Construction of Scientific Research of Beijing Municipal Commission of Education (No.WYJD200902)Funding Project for Science and Technology Program of Beijing Municipal Commission of Education (No.KM 200810037001) is gratefully acknowledged
文摘The floatation of the minerals diaspore and kaolinite was investigated using dodecylamine as the collector.Separating diaspore and kaolinite in a neutral pH pulp is difficult since they then have similar floatability.A depressor consisting of an AlCl3/Na2SiO3 mixture is demonstrated to solve this problem.Diaspore sinking may be seen when the ratio of AlCl3 to Na2SiO3 is 3:1.We refer to this mixture as ATNO.The influence of Al/Si ratio in the feedstock and the grain size of fed minerals on separation was examined.An Al/Si ratio in the concentrate greater than 11 may be obtained when the Al/Si ratio of the feed is between 2.53 and 4.96.However,the grain size of the diaspore greatly influences the concentrate grade.Finer grain size of the diaspore(<40 μm) in pulp makes the flotation separation less than ideal,no matter what the kaolinite grain size.
