TS-1/SiO_2 extrudate was post-treated with mixed solution of tetrapropyl ammonium hydroxide(TPAOH)and various ammonium salts solution(NH_4F,(NH_4)_3PO_4,(NH_4)_2CO_3,(NH_4)_2SO_4,NH_4CH_3CO_2,NH_4NO_3,NH_4Cl and(NH_4)...TS-1/SiO_2 extrudate was post-treated with mixed solution of tetrapropyl ammonium hydroxide(TPAOH)and various ammonium salts solution(NH_4F,(NH_4)_3PO_4,(NH_4)_2CO_3,(NH_4)_2SO_4,NH_4CH_3CO_2,NH_4NO_3,NH_4Cl and(NH_4)_2TiF_6).The obtained hierarchical TS-1 catalysts were characterized by many techniques and tested for propylene epoxidation using hydrogen peroxide as an oxidant in a fixed-bed reactor.It was shown that the physicochemical and catalytic properties of the treated TS-1/SiO_2 extrudate depended on the types of ammonium salts added.Compared to the treatment with TPAOH alone,the treatment with a mixed solution of TPAOH and some ammonium salts can greatly improve the catalytic properties of the treated TS-1/SiO_2 extrudate.Some of these ammonium salts were favorable for the incorporation of titanium in the framework,and the beneficial effect depended on the types of ammonium salt.TS-1/SiO_2 extrudate treated with a mixed solution of TPAOH and(NH_4)_3PO_4 exhibited the highest catalyst stability in propylene epoxidation.Such catalytic property can be correlated to high crystallinity,more framework titanium,large specific surface area and large external surface area.展开更多
[Objective] The aim of this study was to investigate the effects of salt stress on cell expansion in Arabidopsis thaliana rosette leaves.[Method] Arabidopsis seedlings were treated by sodium chloride at the concentrat...[Objective] The aim of this study was to investigate the effects of salt stress on cell expansion in Arabidopsis thaliana rosette leaves.[Method] Arabidopsis seedlings were treated by sodium chloride at the concentration of 0,100 or 150 mmol/L. At the 7th and 14th d of treatment,with nail enamel printing mark method and computer software,the leaf blades area and abaxial epidermal pavement cells area was measured and compared using statistical analysis in Excel. [Result] The growth of Arabidopsis rosette leaves was inhibited under salt stress. Leaves treated for 7 or 14 d expanded less compared with controls. The salt-mediated decrease in leaf expansion is associated with a decrease in abaxial pavement cell expansion. [Conclusion] The decreased leaf and epidermal cell expansion under salt stress is the most important characteristic of plant physiological response to salt stress.展开更多
The lack of fresh water in the world makes the search for an effective method to decontaminate water an urgent priority.An important step is to remove different multivalent ions in salt treatment.Nanofiltration(NF)has...The lack of fresh water in the world makes the search for an effective method to decontaminate water an urgent priority.An important step is to remove different multivalent ions in salt treatment.Nanofiltration(NF)has been used for treating water containing different kinds of salts.In this work,sulfonate group-modified graphene oxide(SGO)was prepared,and added during the interfacial polymerization(IP)reaction to prepare SGO-modifiedNF membranes(PA-SGO).The chemical composition,structure and surface properties of PA and PA-SGO membranes were characterized by FT-IR,XPS,SEM,AFM,contact angle and zeta potential measurements.Their water flux,salt rejection and antifouling abilities were investigated systematically.The testing results showed that the water flux of PA-SGO(0.03%SGO)was 45.85 LMH under a pressure of 0.2 MPa,and the salt rejection varied in the order of Na_2SO_4(98.99%)>MgSO_4(91.25%)>MgCl_2(42.27%)>NaCl(21.96%).An anti-fouling experiment indicated that the PA-SGO membrane had good anti-fouling properties because of its decreased roughness and increased hydrophilicity and electronegativity.The PA-SGO membrane has good potential for use in removing salt ions from water.展开更多
基金supported by National Natural Science Foundation of China (No. 21276183)
文摘TS-1/SiO_2 extrudate was post-treated with mixed solution of tetrapropyl ammonium hydroxide(TPAOH)and various ammonium salts solution(NH_4F,(NH_4)_3PO_4,(NH_4)_2CO_3,(NH_4)_2SO_4,NH_4CH_3CO_2,NH_4NO_3,NH_4Cl and(NH_4)_2TiF_6).The obtained hierarchical TS-1 catalysts were characterized by many techniques and tested for propylene epoxidation using hydrogen peroxide as an oxidant in a fixed-bed reactor.It was shown that the physicochemical and catalytic properties of the treated TS-1/SiO_2 extrudate depended on the types of ammonium salts added.Compared to the treatment with TPAOH alone,the treatment with a mixed solution of TPAOH and some ammonium salts can greatly improve the catalytic properties of the treated TS-1/SiO_2 extrudate.Some of these ammonium salts were favorable for the incorporation of titanium in the framework,and the beneficial effect depended on the types of ammonium salt.TS-1/SiO_2 extrudate treated with a mixed solution of TPAOH and(NH_4)_3PO_4 exhibited the highest catalyst stability in propylene epoxidation.Such catalytic property can be correlated to high crystallinity,more framework titanium,large specific surface area and large external surface area.
文摘[Objective] The aim of this study was to investigate the effects of salt stress on cell expansion in Arabidopsis thaliana rosette leaves.[Method] Arabidopsis seedlings were treated by sodium chloride at the concentration of 0,100 or 150 mmol/L. At the 7th and 14th d of treatment,with nail enamel printing mark method and computer software,the leaf blades area and abaxial epidermal pavement cells area was measured and compared using statistical analysis in Excel. [Result] The growth of Arabidopsis rosette leaves was inhibited under salt stress. Leaves treated for 7 or 14 d expanded less compared with controls. The salt-mediated decrease in leaf expansion is associated with a decrease in abaxial pavement cell expansion. [Conclusion] The decreased leaf and epidermal cell expansion under salt stress is the most important characteristic of plant physiological response to salt stress.
基金supported by the National Natural Science Foundation of China (Nos. 21476248, 21878323, 21736001, 21776153)Major Science and Technology Program for Water Pollution Control and Treatment (No.2015ZX07406006)the Youth Innovation Promotion Association of CAS (No. 2011039)
文摘The lack of fresh water in the world makes the search for an effective method to decontaminate water an urgent priority.An important step is to remove different multivalent ions in salt treatment.Nanofiltration(NF)has been used for treating water containing different kinds of salts.In this work,sulfonate group-modified graphene oxide(SGO)was prepared,and added during the interfacial polymerization(IP)reaction to prepare SGO-modifiedNF membranes(PA-SGO).The chemical composition,structure and surface properties of PA and PA-SGO membranes were characterized by FT-IR,XPS,SEM,AFM,contact angle and zeta potential measurements.Their water flux,salt rejection and antifouling abilities were investigated systematically.The testing results showed that the water flux of PA-SGO(0.03%SGO)was 45.85 LMH under a pressure of 0.2 MPa,and the salt rejection varied in the order of Na_2SO_4(98.99%)>MgSO_4(91.25%)>MgCl_2(42.27%)>NaCl(21.96%).An anti-fouling experiment indicated that the PA-SGO membrane had good anti-fouling properties because of its decreased roughness and increased hydrophilicity and electronegativity.The PA-SGO membrane has good potential for use in removing salt ions from water.
