The enhanced composite nanofibers have attracted great attention for application in recent years. The electrospinning technique was considered to be a prospective production pattern for them. This paper provided a pro...The enhanced composite nanofibers have attracted great attention for application in recent years. The electrospinning technique was considered to be a prospective production pattern for them. This paper provided a promising technique to prepare the polyacrylonitrile （PAN）/halloysite nanotube （HNT） composite nanofbers by using the electrospinning method. The PAN/HNTs composite nanofbers with well enhanced performance were successfully fabricated from a mixture of PAN/DMF/HNTs dispersion solution processed by the electrospinning technique. For achieving good dispersion in PAN polymer, the highly dispersed HNTs were obtained by using polycarboxylate modifcation employing the in-situ spray-drying method. The structure and properties of the composite nanofbers were characterized by TEM, XRD, EDX, IR, and DSC techniques. The obtained PAN/HNTs composite nanofbers with different HNTs contents were about 300-500 nm in diameter. In addition, the mechanical properties of PAN/HNTs composite nanofbers were tested, which exhibited an excellently enhanced performance.展开更多
The paper was aimed at the PMMA/HNTs composite nanofibers with well enhanced mechanical properties prepared by electrospinning technique for the first time. A series of characterizations were used to illustrate the st...The paper was aimed at the PMMA/HNTs composite nanofibers with well enhanced mechanical properties prepared by electrospinning technique for the first time. A series of characterizations were used to illustrate the structure and properties of the composite nanofibers by SEM, XRD, FTIR and DSC techniques. The effect of the PMMA/HNTs composite nanofibers in relationship to the mass percentage of HNTs was investigated. The results indicated that HNTs wrapped in polymer matrix were highly oriented and dispersed by the electrospinning technique, resulting in improved thermal stability of the polymer. Moreover, the mechanical properties of the PMMA/HNTs composite nanofibers which were dependent on HNTs mass content were measured, and good enhanced mechanical properties were obtained.展开更多
The polypropylene(PP) nanocomposites filled with pretreated halloysite nanotubes(HNTs) were prepared by the melt-blending method. Before filling, the as-received HNTs powder was at first purified and then modified. Th...The polypropylene(PP) nanocomposites filled with pretreated halloysite nanotubes(HNTs) were prepared by the melt-blending method. Before filling, the as-received HNTs powder was at first purified and then modified. The characterization tests showed that the purified HNTs had less impurity and more uniform pore size distribution and the surface hydrophobicity of the modified HNTs was obviously improved. The mechanical and tribological properties of the PP/HNTs nanocomposites were extensively investigated. The results showed that the tensile, bending and notched impact strength of the PP/HNTs nanocomposites was somewhat improved, but the wear resistance of the PP/HNTs nanocomposites was obviously enhanced.展开更多
In the maritime industry, cost-effective and lightweight Fiber Reinforced Polymer (FRP) composites offer excellent mechanical properties, design flexibility, and corrosion resistance. However, their reliability in har...In the maritime industry, cost-effective and lightweight Fiber Reinforced Polymer (FRP) composites offer excellent mechanical properties, design flexibility, and corrosion resistance. However, their reliability in harsh seawater conditions is a concern. Researchers address this by exploring three approaches: coating fiber surfaces, hybridizing fibers and matrices with or without nanofillers, and interply rearrangement. This study focuses on evaluating the synergistic effects of interply rearrangement of glass/carbon fibers and hybrid nanofillers, specifically Multi-walled carbon nanotubes (MWCNT) and Halloysite nanotubes (HNT). The aim is to enhance impact properties by minimizing moisture absorption. Hybrid nanocomposites with equal-weight proportions of two nanofillers: 0 wt.%, 1 wt.%, and 2 wt.% were exposed to seawater for 90 days. Experimental data was subjected to modelling through the application of Predictive Fick’s Law. The study found that the hybrid composite containing 2 wt.% hybrid nanofillers exhibited a 22.10% increase in impact performance compared to non-modified counterparts. After 90 days of seawater aging, the material exhibited enhanced resistance to moisture absorption (15.74%) and minimal reduction in impact strength (8.52%) compared to its dry strength, with lower diffusion coefficients.展开更多
Improving the mixing way of fillers and polymer before molding was demonstrated to be a promising approach in the past. In this study, we investigated the effects of the mixing method and the dispersed solvent on the ...Improving the mixing way of fillers and polymer before molding was demonstrated to be a promising approach in the past. In this study, we investigated the effects of the mixing method and the dispersed solvent on the mechanical and friction performance of halloysite nanotubes (HNTs)-filled polytetrafluoroethylene (PTFE) (HNTs/PTFE). After evenly mixing in solution, the HNTs/PTFE mixtures were formed into disc-like nanocomposites by the cold compression molding method. The mechanical performance showed that the tensile strength of the HNTs/PTFE nanocomposites prepared by employing the solution mixing method was about 3—5 MPa more and the Young’s modulus was increased by about 1.2 times greater than those prepared by employing the drying mixing method, but unfortunately they had a poorer elongation at break. Alternatively, it was noteworthy that the wear resistance of the nanocomposites prepared by employing the solution mixing method was improved by 5—10 times and 11—20 times as compared to those formed via the drying mixing method and pure PTFE, respectively. The results showed that the PTFE nanocomposites filled with HNTs by using the solution mixing method exhibited an excellent antiwear performance and had a desirable processability.展开更多
The selective oxidation of cyclohexene to 2-cyclohexene-1-ol and 2-cyclohexene-1-one has been investi-gated over Au/HNTs (HNTs: halloysite nanotubes) catalysts with molecular oxygen in a solvent-free system. The catal...The selective oxidation of cyclohexene to 2-cyclohexene-1-ol and 2-cyclohexene-1-one has been investi-gated over Au/HNTs (HNTs: halloysite nanotubes) catalysts with molecular oxygen in a solvent-free system. The catalysts were prepared by deposition precipitation method and characterized by ICP-AES, TEM and XRD. The results show that the catalytic performance of Au/HNTs is quite well and the catalytic activity over recycled catalyst remains highly. Moreover, the nano-size effect of gold is also reported for the reaction.展开更多
In the present study, we have cloned the gene of human neurotrophin3 (hNT3) from the genomic DNA of white blood cells (WBC) by polymerase chain reaction (PCR). The amplification products were cloned into pUC19 and seq...In the present study, we have cloned the gene of human neurotrophin3 (hNT3) from the genomic DNA of white blood cells (WBC) by polymerase chain reaction (PCR). The amplification products were cloned into pUC19 and sequenced. Genomic sequence comparison of the cloned fragment and the reported hNT3 (GenBank M61180) reveals 7 base differences: 1 in the signal peptide, 3 in the prepro peptide, and 3 in the mature hNT3. Except the 2 varied bases (16th, T to G; 285th, A to C) in the signal peptide and prosequence resulted in the change of their encoded aminoacids (TyrAsp; GlnHis), the other varied bases have no influence on their respective encoded aminoacids, and all the changes have no influence on the open reading frame (ORF) of the hNT3.展开更多
基金supported by the Talent Introduction Fund of Yangzhou University (2012)the Key Research Project-Industry Foresight and General Key Technology of Yangzhou (YZ2015020)+4 种基金the Innovative Talent Program of Green Young Golden Phoenix (yzlyjfjh2015CX073)the Yangzhou Social Development Project (YZ2016072)the Six Talent Peaks of Jiangsu province (2014-XCL-013)the Jiangsu Province Science and Technology Support Project (BE2014613)the Jiangsu Industrial-Academic-Research Prospective Joint Project ( BY2016069-02)
文摘The enhanced composite nanofibers have attracted great attention for application in recent years. The electrospinning technique was considered to be a prospective production pattern for them. This paper provided a promising technique to prepare the polyacrylonitrile （PAN）/halloysite nanotube （HNT） composite nanofbers by using the electrospinning method. The PAN/HNTs composite nanofbers with well enhanced performance were successfully fabricated from a mixture of PAN/DMF/HNTs dispersion solution processed by the electrospinning technique. For achieving good dispersion in PAN polymer, the highly dispersed HNTs were obtained by using polycarboxylate modifcation employing the in-situ spray-drying method. The structure and properties of the composite nanofbers were characterized by TEM, XRD, EDX, IR, and DSC techniques. The obtained PAN/HNTs composite nanofbers with different HNTs contents were about 300-500 nm in diameter. In addition, the mechanical properties of PAN/HNTs composite nanofbers were tested, which exhibited an excellently enhanced performance.
基金supported by the Talent Introduction Fund of Yangzhou University(2012)the Key Research Project-Industry Foresight and General Key Technology of Yangzhou(YZ2015020)+3 种基金the Innovative Talent for the Green Yangzhou Golden Phoenix Program(yzlyjfjh2015CX073)the Jiangsu Province Science and Technology Support Project(BE2014613)the Six Talent Peaks of Jiangsu Province(2014-XCL-013)the Project funded by the Priority Academic Program Development of Jiangsu Higher Education Institutions
文摘The paper was aimed at the PMMA/HNTs composite nanofibers with well enhanced mechanical properties prepared by electrospinning technique for the first time. A series of characterizations were used to illustrate the structure and properties of the composite nanofibers by SEM, XRD, FTIR and DSC techniques. The effect of the PMMA/HNTs composite nanofibers in relationship to the mass percentage of HNTs was investigated. The results indicated that HNTs wrapped in polymer matrix were highly oriented and dispersed by the electrospinning technique, resulting in improved thermal stability of the polymer. Moreover, the mechanical properties of the PMMA/HNTs composite nanofibers which were dependent on HNTs mass content were measured, and good enhanced mechanical properties were obtained.
基金supported by the Talent Introduction Fund of the Yangzhou University(2012)the Zhejiang High Technology Research Institute of Yangzhou University(2017)+6 种基金the Key Research Project-Industry Foresight and General Key Technology of Yangzhou(YZ2015020)the Innovative Talent Program of Green Yang Golden Phoenix(yzlyjfjh2015CX073)the Yangzhou Social Development Project(YZ2016072)the Jiangsu Province Six Talent Peaks Project(2014-XCL-013)the Jiangsu Province Science and Technology Support Project(BE2014613)the Jiangsu Industrial-Academic-Research Prospective Joint Project(BY2016069-02)the Project funded by the Priority Academic Program Development of Jiangsu Higher Education Institutions
文摘The polypropylene(PP) nanocomposites filled with pretreated halloysite nanotubes(HNTs) were prepared by the melt-blending method. Before filling, the as-received HNTs powder was at first purified and then modified. The characterization tests showed that the purified HNTs had less impurity and more uniform pore size distribution and the surface hydrophobicity of the modified HNTs was obviously improved. The mechanical and tribological properties of the PP/HNTs nanocomposites were extensively investigated. The results showed that the tensile, bending and notched impact strength of the PP/HNTs nanocomposites was somewhat improved, but the wear resistance of the PP/HNTs nanocomposites was obviously enhanced.
文摘In the maritime industry, cost-effective and lightweight Fiber Reinforced Polymer (FRP) composites offer excellent mechanical properties, design flexibility, and corrosion resistance. However, their reliability in harsh seawater conditions is a concern. Researchers address this by exploring three approaches: coating fiber surfaces, hybridizing fibers and matrices with or without nanofillers, and interply rearrangement. This study focuses on evaluating the synergistic effects of interply rearrangement of glass/carbon fibers and hybrid nanofillers, specifically Multi-walled carbon nanotubes (MWCNT) and Halloysite nanotubes (HNT). The aim is to enhance impact properties by minimizing moisture absorption. Hybrid nanocomposites with equal-weight proportions of two nanofillers: 0 wt.%, 1 wt.%, and 2 wt.% were exposed to seawater for 90 days. Experimental data was subjected to modelling through the application of Predictive Fick’s Law. The study found that the hybrid composite containing 2 wt.% hybrid nanofillers exhibited a 22.10% increase in impact performance compared to non-modified counterparts. After 90 days of seawater aging, the material exhibited enhanced resistance to moisture absorption (15.74%) and minimal reduction in impact strength (8.52%) compared to its dry strength, with lower diffusion coefficients.
基金supported by the Talent Introduction Fund of Yangzhou University (2012)the Key Research Project-Industry Foresight and General Key Technology of Yangzhou (YZ2015020)+4 种基金the Innovative Talent Program of Green Yang Golden Phoenix (yzlyjfjh2015CX073)the Yangzhou Social Development Project (YZ2016072)the Jiangsu Province Six Talent Peaks Project (2014-XCL-013)the Jiangsu Industrial-Academic-Research Prospective Joint Project ( BY2016069-02)the Project Funded by the Priority Academic Program Development of Jiangsu Higher Education Institutions
文摘Improving the mixing way of fillers and polymer before molding was demonstrated to be a promising approach in the past. In this study, we investigated the effects of the mixing method and the dispersed solvent on the mechanical and friction performance of halloysite nanotubes (HNTs)-filled polytetrafluoroethylene (PTFE) (HNTs/PTFE). After evenly mixing in solution, the HNTs/PTFE mixtures were formed into disc-like nanocomposites by the cold compression molding method. The mechanical performance showed that the tensile strength of the HNTs/PTFE nanocomposites prepared by employing the solution mixing method was about 3—5 MPa more and the Young’s modulus was increased by about 1.2 times greater than those prepared by employing the drying mixing method, but unfortunately they had a poorer elongation at break. Alternatively, it was noteworthy that the wear resistance of the nanocomposites prepared by employing the solution mixing method was improved by 5—10 times and 11—20 times as compared to those formed via the drying mixing method and pure PTFE, respectively. The results showed that the PTFE nanocomposites filled with HNTs by using the solution mixing method exhibited an excellent antiwear performance and had a desirable processability.
文摘The selective oxidation of cyclohexene to 2-cyclohexene-1-ol and 2-cyclohexene-1-one has been investi-gated over Au/HNTs (HNTs: halloysite nanotubes) catalysts with molecular oxygen in a solvent-free system. The catalysts were prepared by deposition precipitation method and characterized by ICP-AES, TEM and XRD. The results show that the catalytic performance of Au/HNTs is quite well and the catalytic activity over recycled catalyst remains highly. Moreover, the nano-size effect of gold is also reported for the reaction.
文摘In the present study, we have cloned the gene of human neurotrophin3 (hNT3) from the genomic DNA of white blood cells (WBC) by polymerase chain reaction (PCR). The amplification products were cloned into pUC19 and sequenced. Genomic sequence comparison of the cloned fragment and the reported hNT3 (GenBank M61180) reveals 7 base differences: 1 in the signal peptide, 3 in the prepro peptide, and 3 in the mature hNT3. Except the 2 varied bases (16th, T to G; 285th, A to C) in the signal peptide and prosequence resulted in the change of their encoded aminoacids (TyrAsp; GlnHis), the other varied bases have no influence on their respective encoded aminoacids, and all the changes have no influence on the open reading frame (ORF) of the hNT3.
