Fluorescent molecules - p-dimethylaminobenzonitrile (DMABN) and trans-stilbene (TSB ) - were used as probes to investigate the inner structure of the nanotubular cavities contained in a new polyorganosiloxane (POS) wh...Fluorescent molecules - p-dimethylaminobenzonitrile (DMABN) and trans-stilbene (TSB ) - were used as probes to investigate the inner structure of the nanotubular cavities contained in a new polyorganosiloxane (POS) which was prepared by the hydrosilylation coupling reaction of cis-isotactic ladderlike polyvinylsilsesquioxane (Vi-T) with 1,1,3,3-tetramethyldisiloxane (H-MM) as coupling agent in the presence of catalyst dicyclopentadienyldichloroplatinum (Cp2PtCl2). The results from FTIR spectra and fluorescence spectra in combination with molecular simulation reveal that the cross-section of the nanotubular cavity is nearly rectangular in shape, and is about 0.62 nm in width and about 0.38 nm in height. This work gains in-depth knowledge into the inner structure of the nanotubular cavities of POS and furthermore provides a guide to the selection of proper guest molecules in constructing functional supramolecular clathrate based upon POS.展开更多
Titanium (Ti) implants with TiO2 nanotubular arrays on the surface could regulate cells adhesion, proliferation and differentiation to determine the bone integra- tion. Additionally, the regulation of immune cells c...Titanium (Ti) implants with TiO2 nanotubular arrays on the surface could regulate cells adhesion, proliferation and differentiation to determine the bone integra- tion. Additionally, the regulation of immune cells could improve osteogenesis or lead in appropriate immune reaction. Thus, we evaluate the behavior of RAW 264.7 macrophages on TiO2 nanotubular arrays with a wide range diameter (from 20 to 120 nm) fabricated by an electrochemical anodization process. In this work, the proliferation, cell viability and cytokine/chemokine secretion were evaluated by CCK-8, live/dead staining and ELISA, respectively. SEM and confocal microscopy were used to observe the adhesion morphology. Results showed that the small size nanotube surface was benefit for the macrophages adhesion and proliferation, while larger size surface could reduce the inflammatory response. These findings contribute to the design of immune-regulating Ti implants surface that supports successful implantation.展开更多
A nanocomposite catalyst with a nonstoichiometric titanium oxide loaded on a special nanotubular alumina(γ‐Al2O3‐nt)was developed and used to reduce cinnamaldehyde to cinnamyl alcohol with sacrificial isopropanol,i...A nanocomposite catalyst with a nonstoichiometric titanium oxide loaded on a special nanotubular alumina(γ‐Al2O3‐nt)was developed and used to reduce cinnamaldehyde to cinnamyl alcohol with sacrificial isopropanol,i.e.,a Meerwein‐Ponndorf‐Verley type reaction.The deposition process produced a highly disperse layer of titanium oxide on the surface of aγ‐Al2O3‐nt support.After a reduction treatment,the as‐prepared TiOx/γ‐Al2O3‐nt was a highly efficient catalyst for the hydrogen transfer reaction between isopropanol and cinnamaldehyde.Selectivity for cinnamic alcohol was higher than99%and the conversion of cinnamaldehyde was higher than95%.The regular morphology of theγ‐Al2O3‐nt support with homogeneous surface sites and the uniformly dispersed titanium oxide featured a high concentration surface Ti(III)species.These factors contributed to the high performance of the TiOx/γ‐Al2O3‐nt catalyst.展开更多
Grasping proton transport pathways and mecha-nisms is vital for the application of fuel cell technology.Herein,we screened four guanidinium organosulfonate charge-assisted hydro-gen-bonded organic frameworks(HOFs),nam...Grasping proton transport pathways and mecha-nisms is vital for the application of fuel cell technology.Herein,we screened four guanidinium organosulfonate charge-assisted hydro-gen-bonded organic frameworks(HOFs),namely,GBBS,G3TSPHB,G4TSP,and G6HSPB,which possess high hydrogen-bonded density proton transport networks shaped like nanotubes.These materials were prepared by self-assembly through charge-assisted interactions between guanidinium cations and organo-sulfonate anions,as well as by host-guest regulation.At 80℃ and 93%RH,the proton conductivity of GBBS,G3TSPHB,G4TSP,and G6HSPB can reach 4.56×10^(-2),2.55×10^(-2),4.01×10^(-2),and 10^(-1) cm^(-1),Doping G6HSPB into the Nafion matrix prepared composite membranes for testing the performance of fuel cells.At 80°C and 98%RH,the proton conductivity of 9%-G6HSPB@Nafion reached a maximum value of 1.14×10^(-1) S cm^(-1),which is 2.8 times higher than recast Nafion.The results showed that charge-assisted HOFs with high proton channel density have better proton transport properties,providing a reference for the design of highly proton-conducting materials.展开更多
The Eu(Ⅲ) ion, as a luminescent probe, is incorporated into a novel nanotube-contained polyorganosiloxane (POS), which is obtained by coupling of ladderlike polyvinylsilsesquioxane (Vi-T) with tetramethyldisiloxane (...The Eu(Ⅲ) ion, as a luminescent probe, is incorporated into a novel nanotube-contained polyorganosiloxane (POS), which is obtained by coupling of ladderlike polyvinylsilsesquioxane (Vi-T) with tetramethyldisiloxane (H-MM) via hydrosilylation, to form POS-Eu(Ⅲ) composite. The results from fluorescent study demonstrate that the composite is actually a host-guest clathrate which includes the Eu(Ⅲ) ions in the tubelike cavity of POS and moreover, the supramolecular clathrate exhibits an obvious energy transfer process which converts the UV light absorbed by POS into the visible light generated from the Eu(Ⅲ) luminescence. Molecular simulation also gives support to the formation of such a clathrate and thus results in energy transfer process.展开更多
基金This project was co-funded by National Natural Science Foundation of China,Research Foundation of Molecular Science Centre and Director of Institute of Chemistry,Chinese Academy of Sciences and Foundation of Organic Solid Laboratory,Chinese Academy of Sc
文摘Fluorescent molecules - p-dimethylaminobenzonitrile (DMABN) and trans-stilbene (TSB ) - were used as probes to investigate the inner structure of the nanotubular cavities contained in a new polyorganosiloxane (POS) which was prepared by the hydrosilylation coupling reaction of cis-isotactic ladderlike polyvinylsilsesquioxane (Vi-T) with 1,1,3,3-tetramethyldisiloxane (H-MM) as coupling agent in the presence of catalyst dicyclopentadienyldichloroplatinum (Cp2PtCl2). The results from FTIR spectra and fluorescence spectra in combination with molecular simulation reveal that the cross-section of the nanotubular cavity is nearly rectangular in shape, and is about 0.62 nm in width and about 0.38 nm in height. This work gains in-depth knowledge into the inner structure of the nanotubular cavities of POS and furthermore provides a guide to the selection of proper guest molecules in constructing functional supramolecular clathrate based upon POS.
基金This work was in part supported by the China Postdoctoral Science Foundation (2016M591075) and the Fundamental Research Funds for the Central Universities (2302016FRF-TP-16- 001A1).
文摘Titanium (Ti) implants with TiO2 nanotubular arrays on the surface could regulate cells adhesion, proliferation and differentiation to determine the bone integra- tion. Additionally, the regulation of immune cells could improve osteogenesis or lead in appropriate immune reaction. Thus, we evaluate the behavior of RAW 264.7 macrophages on TiO2 nanotubular arrays with a wide range diameter (from 20 to 120 nm) fabricated by an electrochemical anodization process. In this work, the proliferation, cell viability and cytokine/chemokine secretion were evaluated by CCK-8, live/dead staining and ELISA, respectively. SEM and confocal microscopy were used to observe the adhesion morphology. Results showed that the small size nanotube surface was benefit for the macrophages adhesion and proliferation, while larger size surface could reduce the inflammatory response. These findings contribute to the design of immune-regulating Ti implants surface that supports successful implantation.
基金supported by the National Natural Science Foundation of China (91434101)the National Key R&D Plan (2017YFB0702800)~~
文摘A nanocomposite catalyst with a nonstoichiometric titanium oxide loaded on a special nanotubular alumina(γ‐Al2O3‐nt)was developed and used to reduce cinnamaldehyde to cinnamyl alcohol with sacrificial isopropanol,i.e.,a Meerwein‐Ponndorf‐Verley type reaction.The deposition process produced a highly disperse layer of titanium oxide on the surface of aγ‐Al2O3‐nt support.After a reduction treatment,the as‐prepared TiOx/γ‐Al2O3‐nt was a highly efficient catalyst for the hydrogen transfer reaction between isopropanol and cinnamaldehyde.Selectivity for cinnamic alcohol was higher than99%and the conversion of cinnamaldehyde was higher than95%.The regular morphology of theγ‐Al2O3‐nt support with homogeneous surface sites and the uniformly dispersed titanium oxide featured a high concentration surface Ti(III)species.These factors contributed to the high performance of the TiOx/γ‐Al2O3‐nt catalyst.
基金National Natural Science Foundation of China(31000430)Key Laboratory of Manufacture and Test Techniques for Automo-bile Parts(Chongqing University of Technology)Ministry of Education(09-66-04)
基金supported by the National Natural Science Foundation of China(22075169)the Shaanxi Fundamental Science Research Project for Chemistry and Biology(22JHQ026)the Starting Grants from Shaanxi University of Science and Technology(2016QNBJ-11).
文摘Grasping proton transport pathways and mecha-nisms is vital for the application of fuel cell technology.Herein,we screened four guanidinium organosulfonate charge-assisted hydro-gen-bonded organic frameworks(HOFs),namely,GBBS,G3TSPHB,G4TSP,and G6HSPB,which possess high hydrogen-bonded density proton transport networks shaped like nanotubes.These materials were prepared by self-assembly through charge-assisted interactions between guanidinium cations and organo-sulfonate anions,as well as by host-guest regulation.At 80℃ and 93%RH,the proton conductivity of GBBS,G3TSPHB,G4TSP,and G6HSPB can reach 4.56×10^(-2),2.55×10^(-2),4.01×10^(-2),and 10^(-1) cm^(-1),Doping G6HSPB into the Nafion matrix prepared composite membranes for testing the performance of fuel cells.At 80°C and 98%RH,the proton conductivity of 9%-G6HSPB@Nafion reached a maximum value of 1.14×10^(-1) S cm^(-1),which is 2.8 times higher than recast Nafion.The results showed that charge-assisted HOFs with high proton channel density have better proton transport properties,providing a reference for the design of highly proton-conducting materials.
基金Project supported by the Research Foundation of Molecular Science CenterDirector of Institute of Chemistry, the Chinese Academy of SciencesFoundation of Organic Solid Laboratory, the Chinese Academy of Sciences.
文摘The Eu(Ⅲ) ion, as a luminescent probe, is incorporated into a novel nanotube-contained polyorganosiloxane (POS), which is obtained by coupling of ladderlike polyvinylsilsesquioxane (Vi-T) with tetramethyldisiloxane (H-MM) via hydrosilylation, to form POS-Eu(Ⅲ) composite. The results from fluorescent study demonstrate that the composite is actually a host-guest clathrate which includes the Eu(Ⅲ) ions in the tubelike cavity of POS and moreover, the supramolecular clathrate exhibits an obvious energy transfer process which converts the UV light absorbed by POS into the visible light generated from the Eu(Ⅲ) luminescence. Molecular simulation also gives support to the formation of such a clathrate and thus results in energy transfer process.