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2016 Volume 32 Issue 11
2016, 32(11): 1885-1895
doi: 10.11862/CJIC.2016.246
Abstract:
Natural bone is an outcome of a multi-template co-assembly process. Compared to single-template self-assembly, bone-like apatite induced by bi-template exhibits more common features and similarities of natural bone that has attracted a wide attention in field of biomineralization. This paper summarizes the recent research achievements in bi-template-induced biomimetic self-assembled apatite. The design of bi-template molecule and the interactions between the molecular templates have been investigated as well as the regulation mechanism of apatite nucleation. The bi-template co-assembly strategy as a promising clinical application has been applied on many fields ranging from bone/teeth repair, coatings and drug delivery, due to the improved osteoconductive properties and even osteoinductive properties.
Natural bone is an outcome of a multi-template co-assembly process. Compared to single-template self-assembly, bone-like apatite induced by bi-template exhibits more common features and similarities of natural bone that has attracted a wide attention in field of biomineralization. This paper summarizes the recent research achievements in bi-template-induced biomimetic self-assembled apatite. The design of bi-template molecule and the interactions between the molecular templates have been investigated as well as the regulation mechanism of apatite nucleation. The bi-template co-assembly strategy as a promising clinical application has been applied on many fields ranging from bone/teeth repair, coatings and drug delivery, due to the improved osteoconductive properties and even osteoinductive properties.
2016, 32(11): 1896-1904
doi: 10.11862/CJIC.2016.262
Abstract:
Uniform well-defined ZnNiAl-LDHs microspheres have been fabricated via a simple hydrothermal method with Zn(NO3)2·6H2O, Ni(NO3)2·6H2O, Al(NO3)3·9H2O and urea as materials. The phase identification and morphology of the LDHs were characterized by XRD, FTIR, SEM, TEM and N2 adsorption-desorption. And the adsorption performance of ZnNiAl-LDHs and ZnAl-LDHs toward methyl orange (MO) was compared. Results show that ZnNiAl-LDHs microspheres have a three dimensional structure which composed of nanosheets, and their particle size is in the range of 1~2.5 μm. The specific surface area of ZnNiAl-LDHs microspheres is 156 m2·g-1 which is much larger than that of ZnAl-LDHs (38 m2·g-1). The saturation adsorbance of ZnNiAl-LDHs and ZnAl-LDHs toward MO are 329.60 and 143.47 mg·g-1, respectively, which shows that ZnNiAl-LDHs exhibits excellent adsorption performance. The adsorption kinetics and adsorption isotherms of ZnNiAl-LDHs microspheres can be well described by the pseudo-second order kinetic and Langmuir isotherm.
Uniform well-defined ZnNiAl-LDHs microspheres have been fabricated via a simple hydrothermal method with Zn(NO3)2·6H2O, Ni(NO3)2·6H2O, Al(NO3)3·9H2O and urea as materials. The phase identification and morphology of the LDHs were characterized by XRD, FTIR, SEM, TEM and N2 adsorption-desorption. And the adsorption performance of ZnNiAl-LDHs and ZnAl-LDHs toward methyl orange (MO) was compared. Results show that ZnNiAl-LDHs microspheres have a three dimensional structure which composed of nanosheets, and their particle size is in the range of 1~2.5 μm. The specific surface area of ZnNiAl-LDHs microspheres is 156 m2·g-1 which is much larger than that of ZnAl-LDHs (38 m2·g-1). The saturation adsorbance of ZnNiAl-LDHs and ZnAl-LDHs toward MO are 329.60 and 143.47 mg·g-1, respectively, which shows that ZnNiAl-LDHs exhibits excellent adsorption performance. The adsorption kinetics and adsorption isotherms of ZnNiAl-LDHs microspheres can be well described by the pseudo-second order kinetic and Langmuir isotherm.
2016, 32(11): 1905-1910
doi: 10.11862/CJIC.2016.247
Abstract:
Fe(Ⅲ)-doped niobium oxide (Fe-Nb2O5) and Nb2O5 were prepared by the one-step hydrothermal route. Both samples were characterized by X-ray diffraction (XRD), electron microscopy(SEM), Transmission electron microscope(TEM) and so on. The results showed that Fe-Nb2O5 and Nb2O5 were orthorhombic phase. Nb2O5 was irregular particle with the wider size distribution of 50~300 nm, and Fe-Nb2O5 was homogeneous micro/nano sphere with the diameter of 1 μm, which assembled from 50 nm sized nano-particles The porous multistage structure could increase the contact interface between electrode materials and electrolyte. Electrochemical analyses showed that Fe-Nb2O5 has the better rate performance and cycle stability with a discharge capacity of 193.2 mAh·g-1 retained up to 100 cycles at 50 and 108.4 mAh·g-1 at 5 A·g-1, and the possible reasons were analyzed.
Fe(Ⅲ)-doped niobium oxide (Fe-Nb2O5) and Nb2O5 were prepared by the one-step hydrothermal route. Both samples were characterized by X-ray diffraction (XRD), electron microscopy(SEM), Transmission electron microscope(TEM) and so on. The results showed that Fe-Nb2O5 and Nb2O5 were orthorhombic phase. Nb2O5 was irregular particle with the wider size distribution of 50~300 nm, and Fe-Nb2O5 was homogeneous micro/nano sphere with the diameter of 1 μm, which assembled from 50 nm sized nano-particles The porous multistage structure could increase the contact interface between electrode materials and electrolyte. Electrochemical analyses showed that Fe-Nb2O5 has the better rate performance and cycle stability with a discharge capacity of 193.2 mAh·g-1 retained up to 100 cycles at 50 and 108.4 mAh·g-1 at 5 A·g-1, and the possible reasons were analyzed.
2016, 32(11): 1911-1918
doi: 10.11862/CJIC.2016.221
Abstract:
Three lanthanide-organic frameworks[Ln(2,5-tdc)1.5(phen)(H2O)]n (Ln=Gd (1), Tb (2), Dy (3); 2,5-tdc=2,5-thiophenedicarboxylate and phen=1,10-phenanthroline) have been synthesized and characterized by X-ray single-crystal diffraction. Complexes 1~3 feature isostructural 2D structures. The luminescence properties of 1~3 were investigated. Under the excitation of 340 nm, the emission spectrum of complex 1 shows a broad band centre at 366 and 387 nm, which plausibly arises from ligand-centered π*-π transition within the ligands. Complex 2 displays green emission and shows four emission peaks at 491, 545, 588 and 620 nm, corresponding to 5D4→7FJ (J=6~3) transitions of Tb3+ under the excitation of 310 nm. The 5D4 emission decay curve reveals a monoexponential behavior with the lifetime value of (0.123±0.005) ms. The emission spectrum of complex 3 records two peaks of 482 and 575 nm, corresponding to the 4F5/2→6H15/2 and 4F5/2→6H13/2 transition of Dy3+, respectively, under the excitation of 330 nm. Moreover, the fluorescence sensing ability of complex 2 was investigated, revealing that it can be used as a fluorescence probe to detect Cu2+ in aqueous solution. CCDC:1036885, 1; 1036884, 2; 1036886, 3.
Three lanthanide-organic frameworks[Ln(2,5-tdc)1.5(phen)(H2O)]n (Ln=Gd (1), Tb (2), Dy (3); 2,5-tdc=2,5-thiophenedicarboxylate and phen=1,10-phenanthroline) have been synthesized and characterized by X-ray single-crystal diffraction. Complexes 1~3 feature isostructural 2D structures. The luminescence properties of 1~3 were investigated. Under the excitation of 340 nm, the emission spectrum of complex 1 shows a broad band centre at 366 and 387 nm, which plausibly arises from ligand-centered π*-π transition within the ligands. Complex 2 displays green emission and shows four emission peaks at 491, 545, 588 and 620 nm, corresponding to 5D4→7FJ (J=6~3) transitions of Tb3+ under the excitation of 310 nm. The 5D4 emission decay curve reveals a monoexponential behavior with the lifetime value of (0.123±0.005) ms. The emission spectrum of complex 3 records two peaks of 482 and 575 nm, corresponding to the 4F5/2→6H15/2 and 4F5/2→6H13/2 transition of Dy3+, respectively, under the excitation of 330 nm. Moreover, the fluorescence sensing ability of complex 2 was investigated, revealing that it can be used as a fluorescence probe to detect Cu2+ in aqueous solution. CCDC:1036885, 1; 1036884, 2; 1036886, 3.
2016, 32(11): 1919-1930
doi: 10.11862/CJIC.2016.263
Abstract:
Tetrahydropyrido[1,2-a]isoindolone derivatives are potent inhibitors of glycogen synthase kinase 3β (GSK3β) instead of homologous cyclin-dependent kinase 5 (CDK5). Molecular docking, molecular dynamics simulation, and MM/PBSA energy calculation are utilized to reveal the kinase inhibitors' selective mechanism at the molecular level for improving selectivity. Dynamic cross-correlation map (DCCM) analysis is applied to study the effect of the inhibitor on the interactions between each residue in CDK5 and GSK3β. The results of molecular docking indicate that the binding modes of three inhibitors with two kinases are especially similar, and residues in the binding pockets of two kinases are aligned with each other based on the sequence comparing analysis of crystal structures. The analysis of Root Mean Square Deviation (RMSD) with little fluctuation underlies the stability and reliability of systems. Its values of CDK5 (~0.15 nm) are less than GSK3β (~0.17 nm), and the inhibitor with higher value holds stronger flexibility and conformational changes of kinases. In terms of energies, the electrostatic and van der Walls energies are the major interactions for differentiating the activity between the same inhibitor and two kinases. And the polar solvation energy plays pivotal role in discriminating the selectivity of kinase inhibitor. The residue decomposition indicates that the residues Glu97 and Thr138 of GSK3β are the key residues for differentiating the inhibitor selectivity. On the other hand, in the aspect of inter-residue interaction in one kinase, results indicate that the dynamic correlation of residues is different during the binding process of CDK5 and GSK3β with inhibitors. The correlation of Thr138 in the hinge domain of GSK3β with that of residues Val135~Gln206 is positive, while the correlation of Gln85 and Cys83~Ala150 in CDK5 is unclear, which is a key factor to distinguish inhibitor selectivity.
Tetrahydropyrido[1,2-a]isoindolone derivatives are potent inhibitors of glycogen synthase kinase 3β (GSK3β) instead of homologous cyclin-dependent kinase 5 (CDK5). Molecular docking, molecular dynamics simulation, and MM/PBSA energy calculation are utilized to reveal the kinase inhibitors' selective mechanism at the molecular level for improving selectivity. Dynamic cross-correlation map (DCCM) analysis is applied to study the effect of the inhibitor on the interactions between each residue in CDK5 and GSK3β. The results of molecular docking indicate that the binding modes of three inhibitors with two kinases are especially similar, and residues in the binding pockets of two kinases are aligned with each other based on the sequence comparing analysis of crystal structures. The analysis of Root Mean Square Deviation (RMSD) with little fluctuation underlies the stability and reliability of systems. Its values of CDK5 (~0.15 nm) are less than GSK3β (~0.17 nm), and the inhibitor with higher value holds stronger flexibility and conformational changes of kinases. In terms of energies, the electrostatic and van der Walls energies are the major interactions for differentiating the activity between the same inhibitor and two kinases. And the polar solvation energy plays pivotal role in discriminating the selectivity of kinase inhibitor. The residue decomposition indicates that the residues Glu97 and Thr138 of GSK3β are the key residues for differentiating the inhibitor selectivity. On the other hand, in the aspect of inter-residue interaction in one kinase, results indicate that the dynamic correlation of residues is different during the binding process of CDK5 and GSK3β with inhibitors. The correlation of Thr138 in the hinge domain of GSK3β with that of residues Val135~Gln206 is positive, while the correlation of Gln85 and Cys83~Ala150 in CDK5 is unclear, which is a key factor to distinguish inhibitor selectivity.
2016, 32(11): 1931-1941
doi: 10.11862/CJIC.2016.253
Abstract:
Microcrystals of Ni(Ⅱ), Co(Ⅱ) and Zn(Ⅱ) coordination polymers based on 4,4'-oxybisbenzoic acid (oba) and 4,4'-bipyridine (4,4'-bpy) with sizes ranging from 10 to 250 μm were prepared hydrothermally by regulating the amount of NEt3, reaction time and reaction temperature. The crystal sizes, morphologies and structures were characterized and analyzed by scanning electron microscopy (SEM) and X-ray powder diffraction (XRPD). Photocatalytic measurements demonstrate that three polymers have excellent degradation capacities of organic dyes such as rhodamine B (RhB), methyl orange (MO) and methylene blue (MB) and the degradation rate increases with the decrease of catalyst sizes. Remarkably, the photocatalytic performance of Ni(Ⅱ) complex (30 μm) for RhB exceeds that of the nano-sized TiO2 under same experimental conditions. In addition, XRPD studies show three coordination polymers are structurally stable after one cycle of photodegradation and thus can be utilized repeatedly as photocatalysts.
Microcrystals of Ni(Ⅱ), Co(Ⅱ) and Zn(Ⅱ) coordination polymers based on 4,4'-oxybisbenzoic acid (oba) and 4,4'-bipyridine (4,4'-bpy) with sizes ranging from 10 to 250 μm were prepared hydrothermally by regulating the amount of NEt3, reaction time and reaction temperature. The crystal sizes, morphologies and structures were characterized and analyzed by scanning electron microscopy (SEM) and X-ray powder diffraction (XRPD). Photocatalytic measurements demonstrate that three polymers have excellent degradation capacities of organic dyes such as rhodamine B (RhB), methyl orange (MO) and methylene blue (MB) and the degradation rate increases with the decrease of catalyst sizes. Remarkably, the photocatalytic performance of Ni(Ⅱ) complex (30 μm) for RhB exceeds that of the nano-sized TiO2 under same experimental conditions. In addition, XRPD studies show three coordination polymers are structurally stable after one cycle of photodegradation and thus can be utilized repeatedly as photocatalysts.
2016, 32(11): 1942-1950
doi: 10.11862/CJIC.2016.225
Abstract:
10-Methylphenothiazine/2-hydroxypropyl-β-cyclodextrin guest-host compounds were mixed with single-walled carbon nanotubes to give composite materials MPT-HP-β-CD/MWNT by a two-step method, which were characterized by FT-IR, UV-Vis, fluorescence spectroscopy, Raman spectrum and TEM. The applications of these composite materials toward the catalytic oxidation of glutathione (GSH) were demonstrated by cyclic voltammetry measurements. These results proved that the presence of MWNT could improve the electrical conductivity and catalytic activity of the composite material. The influences of the pH value, temperature, and scan rate on the catalyst activity were examined. These studies suggest that the MPT-HP-β-CD/MWNT composite materials could be used for the electrochemical detection of GSH with good stability and reproducibility and high sensitivity. The optimal detection concentration is 5×10-7~4.95×10-5 mol·L-1 and the detection limit is 3.96×10-8 mol·L-1 (S/N=3).
10-Methylphenothiazine/2-hydroxypropyl-β-cyclodextrin guest-host compounds were mixed with single-walled carbon nanotubes to give composite materials MPT-HP-β-CD/MWNT by a two-step method, which were characterized by FT-IR, UV-Vis, fluorescence spectroscopy, Raman spectrum and TEM. The applications of these composite materials toward the catalytic oxidation of glutathione (GSH) were demonstrated by cyclic voltammetry measurements. These results proved that the presence of MWNT could improve the electrical conductivity and catalytic activity of the composite material. The influences of the pH value, temperature, and scan rate on the catalyst activity were examined. These studies suggest that the MPT-HP-β-CD/MWNT composite materials could be used for the electrochemical detection of GSH with good stability and reproducibility and high sensitivity. The optimal detection concentration is 5×10-7~4.95×10-5 mol·L-1 and the detection limit is 3.96×10-8 mol·L-1 (S/N=3).
2016, 32(11): 1951-1958
doi: 10.11862/CJIC.2016.258
Abstract:
A series of Y zeolite supported Cu catalysts (CuY) with Cu loading of 6.4% were prepared by wet impregnation method and investigated in oxidative carbonylation of methanol. The microstructure and surface properties of the catalysts were characterized by X-ray diffraction (XRD), H2-temperature program reduction (H2-TPR), NH3-temperature program desorption (NH3-TPD), transmission electron microscope(TEM) techniques. With the increase of H+ content, the Y zeolite supports were more conductive to the cation exchangment with Cu2+, leading to well dispersed Cu species in cages. Above all, the non-exchanged Na+ of Y zeolite resulted in more Cu species located in the super cages. After calcination, the copper species converted into Cu+, which enhanced the catalytic activity of oxidative carbonylation of methanol. The introduction of Cu species into Y zeolite produced moderate acid sites and the amount of acid was also increased with the increase of Cu species located in the cages, As a result, the reaction product distribution varied and the selectivity of DMC decreased with the increase of H+ content. The CuY catalyst prepared by incipient-wetness impregnation method gave 92.3% selectivity of DMC, whereas the Cu catalyst supported on NaY zeolite by wet impregnation method gave 82.4% selectivity of DMC and high space-time yield (STY) of DMC, 109.1 mg·g-1·h-1.
A series of Y zeolite supported Cu catalysts (CuY) with Cu loading of 6.4% were prepared by wet impregnation method and investigated in oxidative carbonylation of methanol. The microstructure and surface properties of the catalysts were characterized by X-ray diffraction (XRD), H2-temperature program reduction (H2-TPR), NH3-temperature program desorption (NH3-TPD), transmission electron microscope(TEM) techniques. With the increase of H+ content, the Y zeolite supports were more conductive to the cation exchangment with Cu2+, leading to well dispersed Cu species in cages. Above all, the non-exchanged Na+ of Y zeolite resulted in more Cu species located in the super cages. After calcination, the copper species converted into Cu+, which enhanced the catalytic activity of oxidative carbonylation of methanol. The introduction of Cu species into Y zeolite produced moderate acid sites and the amount of acid was also increased with the increase of Cu species located in the cages, As a result, the reaction product distribution varied and the selectivity of DMC decreased with the increase of H+ content. The CuY catalyst prepared by incipient-wetness impregnation method gave 92.3% selectivity of DMC, whereas the Cu catalyst supported on NaY zeolite by wet impregnation method gave 82.4% selectivity of DMC and high space-time yield (STY) of DMC, 109.1 mg·g-1·h-1.
2016, 32(11): 1959-1964
doi: 10.11862/CJIC.2016.264
Abstract:
Nano SO42-/ZrO2 solid acid catalysts were prepared by two-step crystallization-post impregnation method and their catalytic performance in the transesterification of vegetable oil with methanol was investigated. The results of XRD, N2 adsorption-desorption and TEM showed that the single tetragonal phase catalyst calcined at 600℃ was composed of nano crystals about 5~10 nm and had the specific surface area of 137 m2·g-1 and the pore size of 3.7 nm. NH3-TPD data indicated that the calcination temperature could improve the content and intensity of the surface acid, and that more superacid content was favorable to effect the efficient conversion under general conditions. In the transesterification reaction, under the operating conditions of 5%(w/w) of catalyst calcined at 600℃, the molar ratio of methanol to oil 20:1, at 135℃ and for 6 h, vegetable oil could be completely converted to fatty acid methyl esters. Compared with the traditional SO42-/ZrO2 catalyst, the nano SO42-/ZrO2 catalyst had a higher catalytic performance and good reuse at low reaction temperature.
Nano SO42-/ZrO2 solid acid catalysts were prepared by two-step crystallization-post impregnation method and their catalytic performance in the transesterification of vegetable oil with methanol was investigated. The results of XRD, N2 adsorption-desorption and TEM showed that the single tetragonal phase catalyst calcined at 600℃ was composed of nano crystals about 5~10 nm and had the specific surface area of 137 m2·g-1 and the pore size of 3.7 nm. NH3-TPD data indicated that the calcination temperature could improve the content and intensity of the surface acid, and that more superacid content was favorable to effect the efficient conversion under general conditions. In the transesterification reaction, under the operating conditions of 5%(w/w) of catalyst calcined at 600℃, the molar ratio of methanol to oil 20:1, at 135℃ and for 6 h, vegetable oil could be completely converted to fatty acid methyl esters. Compared with the traditional SO42-/ZrO2 catalyst, the nano SO42-/ZrO2 catalyst had a higher catalytic performance and good reuse at low reaction temperature.
2016, 32(11): 1965-1972
doi: 10.11862/CJIC.2016.245
Abstract:
The in-situ growth method were used to produce the[Fe(Htrz)2(trz)](BF4)-GO nanocomposites due to the abundant oxygen functional groups on the surface of the GO templates. The[Fe(Htrz)2(trz)](BF4)-GO nanocomposites have been characterized by PXRD, FTIR, SEM, TEM, Raman spectra. The peaks of FTIR and PXRD patterns of the nanocomposites are nearly the superposition of the spectra of individual GO and[Fe(Htrz)2(trz)](BF4), demonstrating the successful formation of spin crossover-graphene oxide nanocomposites. SEM and TEM analysis intuitively shows the cubic[Fe(Htrz)2(trz)](BF4) nanoparticles uniformly anchored on the surface of GO. Additionally, with the assembly time increasing, the quantity and size of[Fe(Htrz)2(trz)](BF4) on the surface of the GO increase gradually. Raman spectra indicates that the intensity ratio of the D to G band (ID/IG) increases after the[Fe(Htrz)2(trz)](BF4) loaded onto the surface of GO, which reveals that the defects in GO materials structures increase, and the interaction between[Fe(Htrz)2(trz)](BF4) nanoparticles and GO strengthens. Magnetic measurement manifests the transition temperatures of SCO-GO nanocomposites with different assembly time (1, 6, 12 h) are 381.1, 381.5 and 382.4 K in warming, 345.9, 345.0 and 344.8 K in cooling with the hysteresis width of 35.2, 36.5 and 37.6 K, respectively. This is attributed to the variation in the capacity and size of[Fe(Htrz)2(trz)](BF4) in SCO-GO nanocomposites with different assembly time. The result of DSC analysis is consistent with the magnetic result, confirming that the spin transition temperatures of SCO-GO nanocomposites move to high temperature.
The in-situ growth method were used to produce the[Fe(Htrz)2(trz)](BF4)-GO nanocomposites due to the abundant oxygen functional groups on the surface of the GO templates. The[Fe(Htrz)2(trz)](BF4)-GO nanocomposites have been characterized by PXRD, FTIR, SEM, TEM, Raman spectra. The peaks of FTIR and PXRD patterns of the nanocomposites are nearly the superposition of the spectra of individual GO and[Fe(Htrz)2(trz)](BF4), demonstrating the successful formation of spin crossover-graphene oxide nanocomposites. SEM and TEM analysis intuitively shows the cubic[Fe(Htrz)2(trz)](BF4) nanoparticles uniformly anchored on the surface of GO. Additionally, with the assembly time increasing, the quantity and size of[Fe(Htrz)2(trz)](BF4) on the surface of the GO increase gradually. Raman spectra indicates that the intensity ratio of the D to G band (ID/IG) increases after the[Fe(Htrz)2(trz)](BF4) loaded onto the surface of GO, which reveals that the defects in GO materials structures increase, and the interaction between[Fe(Htrz)2(trz)](BF4) nanoparticles and GO strengthens. Magnetic measurement manifests the transition temperatures of SCO-GO nanocomposites with different assembly time (1, 6, 12 h) are 381.1, 381.5 and 382.4 K in warming, 345.9, 345.0 and 344.8 K in cooling with the hysteresis width of 35.2, 36.5 and 37.6 K, respectively. This is attributed to the variation in the capacity and size of[Fe(Htrz)2(trz)](BF4) in SCO-GO nanocomposites with different assembly time. The result of DSC analysis is consistent with the magnetic result, confirming that the spin transition temperatures of SCO-GO nanocomposites move to high temperature.
2016, 32(11): 1973-1980
doi: 10.11862/CJIC.2016.261
Abstract:
A large-sized macroporous SiO2 was prepared via a polymer template with three-dimensional (3D) skeletal structure and it was surface functionalized with polydopamine (PDA) by controlling the in situ polymerization of dopamine in its micro-channels to obtain the macroporous composite polydopamine/SiO2 (PDA/SiO2). Samples were characterized by SEM, EDX, MIP, BET, TG-DTA and FTIR. PDA/SiO2 was used to immobilize pseudomonas fluorescens lipase (PFL), immobilization conditions were optimized, and the properties of immobilized and free PFL were studied. The results show that the macroporous SiO2 has 3D continuous pass-through pore structure, the pore sizes are in the range of 300~500 nm. After modification with PDA, the pore walls of the resulting PDA/SiO2 are composed of PDA and SiO2 composite nano-film. The best activity recovery of immobilized lipase is 246% under conditions of immobilizing time of 14 h, pH of 8 and initial PFL concentration 0.4 mg·mL-1. Compared with free PFL, the optimum working temperature and pH ranges of immobilized PFL are both widened, and the thermal stability of immobilized PFL is improved significantly. Immobilized PFL has good operational and storage stabilities. The Km of immobilized PFL is lower than that of free PFL, suggesting a better affinity capacity between PFL and substrate.
A large-sized macroporous SiO2 was prepared via a polymer template with three-dimensional (3D) skeletal structure and it was surface functionalized with polydopamine (PDA) by controlling the in situ polymerization of dopamine in its micro-channels to obtain the macroporous composite polydopamine/SiO2 (PDA/SiO2). Samples were characterized by SEM, EDX, MIP, BET, TG-DTA and FTIR. PDA/SiO2 was used to immobilize pseudomonas fluorescens lipase (PFL), immobilization conditions were optimized, and the properties of immobilized and free PFL were studied. The results show that the macroporous SiO2 has 3D continuous pass-through pore structure, the pore sizes are in the range of 300~500 nm. After modification with PDA, the pore walls of the resulting PDA/SiO2 are composed of PDA and SiO2 composite nano-film. The best activity recovery of immobilized lipase is 246% under conditions of immobilizing time of 14 h, pH of 8 and initial PFL concentration 0.4 mg·mL-1. Compared with free PFL, the optimum working temperature and pH ranges of immobilized PFL are both widened, and the thermal stability of immobilized PFL is improved significantly. Immobilized PFL has good operational and storage stabilities. The Km of immobilized PFL is lower than that of free PFL, suggesting a better affinity capacity between PFL and substrate.
2016, 32(11): 1981-1986
doi: 10.11862/CJIC.2016.249
Abstract:
The flower-like silver sphere structure has been rapidly synthesized by self-assembly of silver nanoflakes through one-step direct mixing of silver nitrate aqueous solution and an aqueous solution containing ferrous sulfate and citric acid. The influence of dropping speed of silver nitrate aqueous solution and the dosage of citric acid on the morphology and size of product were investigated in details through different characteristic methods including X-ray diffraction (XRD) and scanning electron microscopy (SEM). Furthermore, the possible formation mechanism of flower-like silver sphere was explored. The obtained experimental results indicated that the morphology of silver particles could transform from thin flake into flower-like sphere by simply adjusting the dropping speed of silver nitrate aqueous solution. Additionally, this type of nanomaterial exhibited superior catalytic activity for the hydrogenation reduction of p-nitrophenol.
The flower-like silver sphere structure has been rapidly synthesized by self-assembly of silver nanoflakes through one-step direct mixing of silver nitrate aqueous solution and an aqueous solution containing ferrous sulfate and citric acid. The influence of dropping speed of silver nitrate aqueous solution and the dosage of citric acid on the morphology and size of product were investigated in details through different characteristic methods including X-ray diffraction (XRD) and scanning electron microscopy (SEM). Furthermore, the possible formation mechanism of flower-like silver sphere was explored. The obtained experimental results indicated that the morphology of silver particles could transform from thin flake into flower-like sphere by simply adjusting the dropping speed of silver nitrate aqueous solution. Additionally, this type of nanomaterial exhibited superior catalytic activity for the hydrogenation reduction of p-nitrophenol.
2016, 32(11): 1987-1994
doi: 10.11862/CJIC.2016.257
Abstract:
Ag nanoparticles loaded CdMoO4 photocatalysts were prepared via a hydrothermal process followed by the sodium borohydride reduction method. The composition and structure of the catalysts were characterized by X-ray diffraction (XRD), scanning electron microscope (SEM) and transmission electron microscopy (TEM) techniques. The photo-response and surface state of the catalysts were investigated by UV-Vis diffuse reflectance spectroscopy (UV-Vis DRS) and X-ray photoelectron spectroscopy (XPS). The effect of the loaded amount of Ag nanoparticles on the photocatalytic activity of CdMoO4 photocatalyst for the degradation of rhodamine B (RhB) under UV light and the selective oxidation of benzyl alcohol under visible light were investigated. The results showed that the composite photocatalysts exhibited significantly enhanced photocatalytic activity compared to pure CdMoO4. The mechanism was studied by employing chemical scavengers technology, which indicated that O2-·and·OH are the main species in the photocatalytic process.
Ag nanoparticles loaded CdMoO4 photocatalysts were prepared via a hydrothermal process followed by the sodium borohydride reduction method. The composition and structure of the catalysts were characterized by X-ray diffraction (XRD), scanning electron microscope (SEM) and transmission electron microscopy (TEM) techniques. The photo-response and surface state of the catalysts were investigated by UV-Vis diffuse reflectance spectroscopy (UV-Vis DRS) and X-ray photoelectron spectroscopy (XPS). The effect of the loaded amount of Ag nanoparticles on the photocatalytic activity of CdMoO4 photocatalyst for the degradation of rhodamine B (RhB) under UV light and the selective oxidation of benzyl alcohol under visible light were investigated. The results showed that the composite photocatalysts exhibited significantly enhanced photocatalytic activity compared to pure CdMoO4. The mechanism was studied by employing chemical scavengers technology, which indicated that O2-·and·OH are the main species in the photocatalytic process.
2016, 32(11): 1995-2002
doi: 10.11862/CJIC.2016.255
Abstract:
Influencing factors for the synthesis of LSX molecular sieve, such as LSX seed, nK/nNa and crystallization conditions were investigated in detail. The products were characterized by XRD, SEM, XRF, FTIR and N2 adsorption-desorption. The results revealed that the addition of LSX seed could accelerate the rates of crystal nucleation and growth, and inhibit the formation of A type and sodalite zeolites. Furthermore, too high or too low value of nK/nNa in the synthesis gel would obtain A type and sodalite impurities. Crystallization at high temperature directly would lead the conversion of metastable LSX zeolite into more thermodynamically stable zeolite phase. The Si-Al ratio, the surface area and N2 adsorption capacity of the end product decreased with the extending of aging time and the increasing of crystallization temperature.
Influencing factors for the synthesis of LSX molecular sieve, such as LSX seed, nK/nNa and crystallization conditions were investigated in detail. The products were characterized by XRD, SEM, XRF, FTIR and N2 adsorption-desorption. The results revealed that the addition of LSX seed could accelerate the rates of crystal nucleation and growth, and inhibit the formation of A type and sodalite zeolites. Furthermore, too high or too low value of nK/nNa in the synthesis gel would obtain A type and sodalite impurities. Crystallization at high temperature directly would lead the conversion of metastable LSX zeolite into more thermodynamically stable zeolite phase. The Si-Al ratio, the surface area and N2 adsorption capacity of the end product decreased with the extending of aging time and the increasing of crystallization temperature.
2016, 32(11): 2003-2011
doi: 10.11862/CJIC.2016.266
Abstract:
Di-4-methylbenzyltin dichloride has been synthesized via the reaction of the tin powder with the 4-methylbenzyl chloride in the hydrous toluene. Two substituted benzyltin complexes has been synthesized via the reaction of the 2-oxo-propionic acid aroyl hydrazone with the di-4-methylbenzyltin dichloride. The complexes 1 and 2 have been characterized by IR, 1H NMR, 13 NMR spectra, elemental analysis and the crystal structures have been determined by X-ray diffraction. In vitro antitumor activities of both complexes were evaluated by the 3-(4,5-dimethylthiazoly-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay against three human cancer cell lines(MCF-7, HepG2, NCI-H460) and human cell line(HL-7702). Two complexes exhibited strong antitumor activity, moreover, 2 was less toxic than 1. The interaction between complexes and calf thymus DNA were studied by EB fluorescent probe. The interaction of 1 with calf thymus DNA were intercalation and electrostatic attraction, however, that of 2 was only intercalation. CCDC:1487539, 1; 1053263, 2.
Di-4-methylbenzyltin dichloride has been synthesized via the reaction of the tin powder with the 4-methylbenzyl chloride in the hydrous toluene. Two substituted benzyltin complexes has been synthesized via the reaction of the 2-oxo-propionic acid aroyl hydrazone with the di-4-methylbenzyltin dichloride. The complexes 1 and 2 have been characterized by IR, 1H NMR, 13 NMR spectra, elemental analysis and the crystal structures have been determined by X-ray diffraction. In vitro antitumor activities of both complexes were evaluated by the 3-(4,5-dimethylthiazoly-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay against three human cancer cell lines(MCF-7, HepG2, NCI-H460) and human cell line(HL-7702). Two complexes exhibited strong antitumor activity, moreover, 2 was less toxic than 1. The interaction between complexes and calf thymus DNA were studied by EB fluorescent probe. The interaction of 1 with calf thymus DNA were intercalation and electrostatic attraction, however, that of 2 was only intercalation. CCDC:1487539, 1; 1053263, 2.
2016, 32(11): 2012-2016
doi: 10.11862/CJIC.2016.227
Abstract:
Two mononuclear Cu(Ⅰ) complexes,[Cu(mbpy)(dppe)]ClO4 (1) and[Cu(mbpy)(dppp)]ClO4·CH2Cl2 (2), have been synthesized by using 6-methoxycarbonyl-2,2'-bipyridine (mbpy) as N-heterocyclic bidentate chelating ligand and 1,2-bis(diphenylphosphino)ethane (dppe) and 1,3-bis(diphenylphosphino)propane (dppp) as auxiliary ligand. They have been well characterized by elemental analysis, infrared spectroscopy, UV-Vis absorption spectroscopy and single-crystal X-ray diffraction. As revealed by crystal structure analysis, complexes 1 and 2 are all mononuclear Cu(Ⅰ) complexes and the central Cu(Ⅰ) ion coordinates with two N atoms of the 2,2-bipyridyl ring and two P atoms of bisphosphine ligand to generate a distorted tetrahedral configuration. Complexes 1 and 2 have a weak low-energy absorption band in the 350~525 nm region, assigned to charge-transfer transitions with appreciable metal-to-ligand charge-transfer (MLCT) character. CCDC:1493463, 1; 1493464, 2.
Two mononuclear Cu(Ⅰ) complexes,[Cu(mbpy)(dppe)]ClO4 (1) and[Cu(mbpy)(dppp)]ClO4·CH2Cl2 (2), have been synthesized by using 6-methoxycarbonyl-2,2'-bipyridine (mbpy) as N-heterocyclic bidentate chelating ligand and 1,2-bis(diphenylphosphino)ethane (dppe) and 1,3-bis(diphenylphosphino)propane (dppp) as auxiliary ligand. They have been well characterized by elemental analysis, infrared spectroscopy, UV-Vis absorption spectroscopy and single-crystal X-ray diffraction. As revealed by crystal structure analysis, complexes 1 and 2 are all mononuclear Cu(Ⅰ) complexes and the central Cu(Ⅰ) ion coordinates with two N atoms of the 2,2-bipyridyl ring and two P atoms of bisphosphine ligand to generate a distorted tetrahedral configuration. Complexes 1 and 2 have a weak low-energy absorption band in the 350~525 nm region, assigned to charge-transfer transitions with appreciable metal-to-ligand charge-transfer (MLCT) character. CCDC:1493463, 1; 1493464, 2.
2016, 32(11): 2017-2024
doi: 10.11862/CJIC.2016.220
Abstract:
Two compounds, Pd(L1)2 (1) and Pd(L2)2 (2) (L1=(Z)-4-((p-toluidino)methylene)-2,2,5,5-tetramethyl-dihydrofuran-3(2H)-one, L2=(Z)-4-((o-toluidino)methylene)-2,2,5,5-tetramethyl-dihydrofuran-3(2H)-one)), have been synthesized and characterized by elemental analyses, IR spectra, 1H NMR spectra, UV-Vis spectral and single-crystal X-ray diffraction. The crystal structures of compounds are shown to contain a variety of weak interactions. In 1, the C-H…O interactions between the furan O atom and methyl H atom of phenyl ring bridge molecules forming an infinite chain along the c axis, which is interconnected via the weak C-H…H-C interactions and C-H…C interactions, giving rise to a 3D network. In 2, molecules are held together by weak C-H…H-C interactions and C-H…C interactions into a 2D layered framework. CCDC:289373, 1; 629001, 2.
Two compounds, Pd(L1)2 (1) and Pd(L2)2 (2) (L1=(Z)-4-((p-toluidino)methylene)-2,2,5,5-tetramethyl-dihydrofuran-3(2H)-one, L2=(Z)-4-((o-toluidino)methylene)-2,2,5,5-tetramethyl-dihydrofuran-3(2H)-one)), have been synthesized and characterized by elemental analyses, IR spectra, 1H NMR spectra, UV-Vis spectral and single-crystal X-ray diffraction. The crystal structures of compounds are shown to contain a variety of weak interactions. In 1, the C-H…O interactions between the furan O atom and methyl H atom of phenyl ring bridge molecules forming an infinite chain along the c axis, which is interconnected via the weak C-H…H-C interactions and C-H…C interactions, giving rise to a 3D network. In 2, molecules are held together by weak C-H…H-C interactions and C-H…C interactions into a 2D layered framework. CCDC:289373, 1; 629001, 2.
