In this study, multiwalled carbon nanotubes （MWCNTs） were used to encapsulate a model anticancer drug, doxorubicin （Dox）. Then, the drug-loaded MWCNTs （Dox/MWCNTs） with an optimized drug encapsulation percentage...In this study, multiwalled carbon nanotubes （MWCNTs） were used to encapsulate a model anticancer drug, doxorubicin （Dox）. Then, the drug-loaded MWCNTs （Dox/MWCNTs） with an optimized drug encapsulation percentage were mixed with poly（lactide-co-glycolide） （PLGA） polymer solution for subsequent electrospinning to form drug-loaded composite nanofibrous mats. The structure, morphology, and mechanical properties of the formed electrospun Dox/PLGA, MWCNTs/PLGA, and Dox/MWCNTs/PLGA composite nanofibrous mats were characterized using scanning electron microscopy （SEM）, Fourier transform infrared spectroscopy, and tensile testing. In vitro viability assay and SEM morphology observation of mouse fibroblast cells cultured onto the MWCNTs/PLGA fibrous scaffolds demonstrate that the developed MWCNTs/PLGA composite nanofibers are cytocompatible. The incorporation of Dox-loaded MWCNTs within the PLGA nanofibers is able to improve the mechanical durability and maintain the three-dimensional structure of the nanofibrous mats. More importantly, our results indicate that this double-container drug delivery system （both PLGA polymer and MWCNTs are drug carriers） is beneficial to avoid the burst release of the drug and able to release the antitumor drug Dox in a sustained manner for 42 days. The developed composite electrospun nanofibrous drug delivery system may be used as therapeutic scaffold materials for post-operative local chemotherapy.展开更多
Ultrafine polycaprolactone(PCL)fibers containing watersoluble drug tetracycline hydrochloride(Tet)were prepared by emulsion electrospinning.Sorbitan monooleate(Span80)was added as an essential additive to form stable ...Ultrafine polycaprolactone(PCL)fibers containing watersoluble drug tetracycline hydrochloride(Tet)were prepared by emulsion electrospinning.Sorbitan monooleate(Span80)was added as an essential additive to form stable water/oil emulsions and fabricate fibers with core-sheath structure.Different concentrations of Span80(0-40 g/L)were used to investigate the stability of emulsion and size of dispersed droplets.The scanning electron microscope(SEM)images indicated that the morphology of the fibers with Span80 were beaded-free with diameters of 200-400 nm,and Span80 enhanced the spinnability of electrospinning solution.The laser scanning confocal microscope(LSCM)images indicated that Tet was well encapsulated into the core region of the PCL fibers.The transmission electron microscope(TEM)image showed the formation of core-sheath structure.The loading efficiency(LE)and entrapment efficiency(EE)of Tet were calculated and release profiles in artificial saliva buffer solution(pH=6.8)were also analyzed.The results revealed that LE and EE of fibers with Span80decreased with the increase of its concentration.Fibers with coresheath structure had a longer effective release lifetime than without Span80.The increase of Span80 resulted in higher hydrophilicity of fibers and faster release rate of Tet.展开更多
Negative pressure plays a very important role in compact spinning system.To know airflow field and its distribution is helpful to look into the condensing principle of fiber bundle.Therefore,computational fluid dynami...Negative pressure plays a very important role in compact spinning system.To know airflow field and its distribution is helpful to look into the condensing principle of fiber bundle.Therefore,computational fluid dynamics(CFD)software was used to simulate airflow field in this paper.Airflow velocity distributions both in different fiber layers and under different negative pressures were discussed.The results indicate that airflow velocity in upper layer of the fiber bundle is greater than that in lower layer.Airflow velocities in both X and Y axis directions have a positive correlation with negative pressure.It can provide a theoretical base to make high quality compact yarns in productive practice.展开更多
The effects of coagulation conditions on tensile properties of the regenerated cellulose fibers prepared by wet-spinning from NaOH/thiourea/urea(8∶6.5∶8 by weight)aqueous solvent were investigated by tensile tester,...The effects of coagulation conditions on tensile properties of the regenerated cellulose fibers prepared by wet-spinning from NaOH/thiourea/urea(8∶6.5∶8 by weight)aqueous solvent were investigated by tensile tester,X-ray diffraction(XRD),and scanning electron microscope(SEM).The results show that the tensile properties of the as-spun fibers change with the coagualtion concentration,temperature,and time.When the spinning solution is coagulated in 10% H2SO4/12.5% Na2SO4 aqueous solution,the as-spun fibers have a typical structure of cellulose II,a circular cross-section,and homogeneous morphological structure.展开更多
The influence of mercerization on cotton varieties from Africa,Xinjiang and Australia was studied. The micro-morphology,mechanical property and crystalline structure were analyzed before and after mercerization. Merce...The influence of mercerization on cotton varieties from Africa,Xinjiang and Australia was studied. The micro-morphology,mechanical property and crystalline structure were analyzed before and after mercerization. Mercerization made the surface of fibers smoother which resulted in improved luster of fiberes with better results observed in Australia,Xinjiang and Africa cotton varieties respectively. Although fiber strenth increased due to orientation of intra fiber cellulose chains,there was a general in the crystallinity index amongst the three varieties of cotton after mercerization.Reduced crystallinity is a function of improved processability and thus Australian cotton is more processable than cotton from Africa and Xinjiang.展开更多
Blood stains on the fabric often appear at the scene of the crime. The age determination of blood stains can provide important information to speculate the time of crime. The relationship between the age of blood and ...Blood stains on the fabric often appear at the scene of the crime. The age determination of blood stains can provide important information to speculate the time of crime. The relationship between the age of blood and the bending rigidity of blooded cotton fabric washed was investigated experimentally via the use of FAST-2 bending tester. The bending length of blooded fabric washed at different time was measured and the bending rigidity was calculated.The relationship between the age of blood and the bending rigidity after washing was obtained through curve fitting. The result shows that the bending rigidity of blooded fabric washed is various with the increase of the age of blood stains and this relationship can be used to speculate the age of blood stains. This method provides a new perspective for determining the bloodstain age.展开更多
Automated defect detection in woven fabrics for quality control is still a challenging novelty detection problem,while the efficient representation of fabric texture is essential for it.This paper presents a novel met...Automated defect detection in woven fabrics for quality control is still a challenging novelty detection problem,while the efficient representation of fabric texture is essential for it.This paper presents a novel method for fabric texture representation.Benefiting from the characteristics of the weaving process,the major texture information of woven fabric is concentrated in the warp and weft directions.Thus,the proposed method is firstly to project the image patch along warp and weft directions to obtain projected vectors containing warp and weft informations.Secondly,the obtained vectors instead of image patch,are used to extract the features that are able to represent fabric texture.Finally,the t-test is applied to verifying the usefulness of the proposed method in discriminating defective and normal fabric textures.The experiments on various defective samples demonstrate that the method yields a robust and good performance in representing fabric texture and discriminating defects.展开更多
基金financially supported by the“111 Project”(No.B07024)the Fundamental Research Funds for the Central Universities(for R.Guo,M.Shen and X.Shi)+1 种基金the Program for Professor of Special Appointment(Eastern Scholar)at Shanghai Institutions of Higher Learningthe Program for Innovative Research Team(in Science and Technology)in University of Henan Province(No.13IRTSTHN024)
文摘In this study, multiwalled carbon nanotubes （MWCNTs） were used to encapsulate a model anticancer drug, doxorubicin （Dox）. Then, the drug-loaded MWCNTs （Dox/MWCNTs） with an optimized drug encapsulation percentage were mixed with poly（lactide-co-glycolide） （PLGA） polymer solution for subsequent electrospinning to form drug-loaded composite nanofibrous mats. The structure, morphology, and mechanical properties of the formed electrospun Dox/PLGA, MWCNTs/PLGA, and Dox/MWCNTs/PLGA composite nanofibrous mats were characterized using scanning electron microscopy （SEM）, Fourier transform infrared spectroscopy, and tensile testing. In vitro viability assay and SEM morphology observation of mouse fibroblast cells cultured onto the MWCNTs/PLGA fibrous scaffolds demonstrate that the developed MWCNTs/PLGA composite nanofibers are cytocompatible. The incorporation of Dox-loaded MWCNTs within the PLGA nanofibers is able to improve the mechanical durability and maintain the three-dimensional structure of the nanofibrous mats. More importantly, our results indicate that this double-container drug delivery system （both PLGA polymer and MWCNTs are drug carriers） is beneficial to avoid the burst release of the drug and able to release the antitumor drug Dox in a sustained manner for 42 days. The developed composite electrospun nanofibrous drug delivery system may be used as therapeutic scaffold materials for post-operative local chemotherapy.
基金“111 Project” Biomedical Textile Materials Science and Technology,China(No.B07024)
文摘Ultrafine polycaprolactone(PCL)fibers containing watersoluble drug tetracycline hydrochloride(Tet)were prepared by emulsion electrospinning.Sorbitan monooleate(Span80)was added as an essential additive to form stable water/oil emulsions and fabricate fibers with core-sheath structure.Different concentrations of Span80(0-40 g/L)were used to investigate the stability of emulsion and size of dispersed droplets.The scanning electron microscope(SEM)images indicated that the morphology of the fibers with Span80 were beaded-free with diameters of 200-400 nm,and Span80 enhanced the spinnability of electrospinning solution.The laser scanning confocal microscope(LSCM)images indicated that Tet was well encapsulated into the core region of the PCL fibers.The transmission electron microscope(TEM)image showed the formation of core-sheath structure.The loading efficiency(LE)and entrapment efficiency(EE)of Tet were calculated and release profiles in artificial saliva buffer solution(pH=6.8)were also analyzed.The results revealed that LE and EE of fibers with Span80decreased with the increase of its concentration.Fibers with coresheath structure had a longer effective release lifetime than without Span80.The increase of Span80 resulted in higher hydrophilicity of fibers and faster release rate of Tet.
基金Key Project in National Science & Technology Pillar Program,China(No.2007BAE41B04)
文摘Negative pressure plays a very important role in compact spinning system.To know airflow field and its distribution is helpful to look into the condensing principle of fiber bundle.Therefore,computational fluid dynamics(CFD)software was used to simulate airflow field in this paper.Airflow velocity distributions both in different fiber layers and under different negative pressures were discussed.The results indicate that airflow velocity in upper layer of the fiber bundle is greater than that in lower layer.Airflow velocities in both X and Y axis directions have a positive correlation with negative pressure.It can provide a theoretical base to make high quality compact yarns in productive practice.
文摘The effects of coagulation conditions on tensile properties of the regenerated cellulose fibers prepared by wet-spinning from NaOH/thiourea/urea(8∶6.5∶8 by weight)aqueous solvent were investigated by tensile tester,X-ray diffraction(XRD),and scanning electron microscope(SEM).The results show that the tensile properties of the as-spun fibers change with the coagualtion concentration,temperature,and time.When the spinning solution is coagulated in 10% H2SO4/12.5% Na2SO4 aqueous solution,the as-spun fibers have a typical structure of cellulose II,a circular cross-section,and homogeneous morphological structure.
文摘The influence of mercerization on cotton varieties from Africa,Xinjiang and Australia was studied. The micro-morphology,mechanical property and crystalline structure were analyzed before and after mercerization. Mercerization made the surface of fibers smoother which resulted in improved luster of fiberes with better results observed in Australia,Xinjiang and Africa cotton varieties respectively. Although fiber strenth increased due to orientation of intra fiber cellulose chains,there was a general in the crystallinity index amongst the three varieties of cotton after mercerization.Reduced crystallinity is a function of improved processability and thus Australian cotton is more processable than cotton from Africa and Xinjiang.
基金Opening Project of Shanghai Key Laboratory of Crime Scene Evidence,China(No.2014243)Fundamental Research Funds for the Central Universities,China
文摘Blood stains on the fabric often appear at the scene of the crime. The age determination of blood stains can provide important information to speculate the time of crime. The relationship between the age of blood and the bending rigidity of blooded cotton fabric washed was investigated experimentally via the use of FAST-2 bending tester. The bending length of blooded fabric washed at different time was measured and the bending rigidity was calculated.The relationship between the age of blood and the bending rigidity after washing was obtained through curve fitting. The result shows that the bending rigidity of blooded fabric washed is various with the increase of the age of blood stains and this relationship can be used to speculate the age of blood stains. This method provides a new perspective for determining the bloodstain age.
基金National Natural Science Foundations of China(Nos.61501209,61379011)the Foundamental Research Funds for the Central Universities of China(Nos.JUSRP51631A,JUSRP11506)
文摘Automated defect detection in woven fabrics for quality control is still a challenging novelty detection problem,while the efficient representation of fabric texture is essential for it.This paper presents a novel method for fabric texture representation.Benefiting from the characteristics of the weaving process,the major texture information of woven fabric is concentrated in the warp and weft directions.Thus,the proposed method is firstly to project the image patch along warp and weft directions to obtain projected vectors containing warp and weft informations.Secondly,the obtained vectors instead of image patch,are used to extract the features that are able to represent fabric texture.Finally,the t-test is applied to verifying the usefulness of the proposed method in discriminating defective and normal fabric textures.The experiments on various defective samples demonstrate that the method yields a robust and good performance in representing fabric texture and discriminating defects.
