In this paper,the relation between the tensile strength,breaking elongationand the Crystallinity,Orientation of silk was studied,which obtalned from thecocoons with different silk worm races,sexes,cocooning conditions...In this paper,the relation between the tensile strength,breaking elongationand the Crystallinity,Orientation of silk was studied,which obtalned from thecocoons with different silk worm races,sexes,cocooning conditions.The Crystallinity and degree of Crystal Orientation of fibroin were determinedby the X-ray diffraction.and the birefringence of fibroin was measured withInterference microscope.The research showed that the dependence of strength and elongation of rawsilk on Its crystailinity was not so closed.Although there was linear correlation ofstrength with the birefringence and the degree of crystal orientation of fibroin.But the correlation coefficient of the former was larger than the latter.Therefore,adopting birefringence method which would reflected the degree of orlentation ofboth the amorphous and crystalline region of fibroln was suitable for consideringthe strength.The correlation coefficients of strength and elongation withbirefringence were 0.96 and 0.77 respectively.The latter one was展开更多
Films were developed from the modified wheat glutens by microbial transglutamina se(MTGase, [E/S]=10u/g,15u/g and 20u/g) in order to improve physical and barri er properties of the films.Glycerol was used as a plastic...Films were developed from the modified wheat glutens by microbial transglutamina se(MTGase, [E/S]=10u/g,15u/g and 20u/g) in order to improve physical and barri er properties of the films.Glycerol was used as a plasticizer.The films prepared from the modified-glutens by MTGase show a lower elongation at break(E) and a water vapor permeability(WVP), and a higher tensile strength(TS) than the nati ve gluten films.When the modified gluten films by different concentrations of MT Gase are immersed in water at 25℃,their weight losses decreased significantly, and their water resistance increases obviously as expected, compared with the c ontrol gluten films. Moreover, an addition of glycerol as plasticizer greatly mo dified water vapor barrier and mechanical properties of the films.展开更多
Many properties of polyester filaments such as heat shrinkage, tenacity, elongation at break and etc. are greatly influenced by drawing, so post-drawing is important in downstream processing. As more and more profile ...Many properties of polyester filaments such as heat shrinkage, tenacity, elongation at break and etc. are greatly influenced by drawing, so post-drawing is important in downstream processing. As more and more profile fibers and multi-variance fibers used in textile industry, the properties of above two kinds of differential polyester filaments after drawing in different heat conditions were studied. Finally following conclusions were obtained: Firstly, the tenacity and elongation at break decreases with the rise of Tp. Secondly, the tenacity rises but the elongation at break decreases with the increase of Tb. Then, when the Tb is low, both the shrinkage in boiling water and hi hot air decreases with the rise of Tp, while, when the Tb is high, both the shrinkage rises with the rise of Tp. The last, both the shrinkage decreases with the rise of Tb.展开更多
Films were made from the wheat glutens treated with 5%,10%,15%,20%,25% and 30%(wt% of gluten) of sodium dodecyl sulfite (SDS) in order to improve the properties of the films. Glycerol was used as a plasticizer.An addi...Films were made from the wheat glutens treated with 5%,10%,15%,20%,25% and 30%(wt% of gluten) of sodium dodecyl sulfite (SDS) in order to improve the properties of the films. Glycerol was used as a plasticizer.An addition of SDS in wheat glutens prior to forming films significantly increased the elongation at break(E) (P<0.05) and reduced notably the water vapor permeability(WVP) (P<0.05). In contrast,a decrease in the tensile strength(TS) of the films from gluten containing-SDS was found.Moreover,a significant decrease in P_(O_2) and P_(CO_2) of films from gluten treated with SDS was noticed. Although SDS-treated gluten film was slightly more yellow and darker than control one, it was not visually detrimental. It is indicated that the treatment with SDS prior to forming films greatly enhances the mechanical properties of wheat gluten films.The obivous improvement in water vapor permeability and extensibility of gluten films means that the use of SDS is a potential choice for improving properties of gluten films. The edible film was used to preserve tomatoes. The experimental results show that the shelf life of tomatoes coated with the edible film is extended, and the nutritional quality is kept well.展开更多
High frequency ultrasonic nondestructive testing was conducted using a direct contact method for SUS306 stainless steel treated by high temperature and fracture tensile tests. Reflected ultrasonic echoes were analyzed...High frequency ultrasonic nondestructive testing was conducted using a direct contact method for SUS306 stainless steel treated by high temperature and fracture tensile tests. Reflected ultrasonic echoes were analyzed. The relationships between the ultrasonic attenuation coefficient, strength of backscattering wave and the elongation at break of the samples were obtained. The damages were evaluated by using these results together with the analysis of microstructure and mechanics of the tested material.展开更多
A matured canola plant has different types of stems based on the diameter, such as narrow (immature), medium (mature), and wide (over mature). Therefore, t<span style="font-family:Verdana;">his study w...A matured canola plant has different types of stems based on the diameter, such as narrow (immature), medium (mature), and wide (over mature). Therefore, t<span style="font-family:Verdana;">his study was focused on investigating the properties of the extracted canola (HYREAR 3) fibers from 3 different diameter of stems (narrow, medium and wide). The physical (average length, aspect ratio, contact angle, and moisture regain) and mechanical (load at break, elongation at break, tensile stress, young’s modulus, and tenacity) properties of fibers were measured. ANOVA showed that stem diameter had effects on all fiber properties except for average length and elongation at break. Fiber diameter also had significant effects on load at break, elongation at break, aspect ratio, tensile stress, and young’s modulus. In corrgram, it was found that tensile stress, young’s modulus, and aspect ratio were negatively correlated to fiber diameter whereas load at break and tenacity were positively associated. Mean values showed that stem diameter had effects on all fiber properties except for average length. The mean values of fiber diameter, load at break, elongation at break, tenacity, and contact angle were highest and the lowest mean values were observed for tensile stress, young’s modulus and aspect ratio in fibers of 7</span><span style="font-family:Verdana;"> </span><span style="font-family:Verdana;">-</span><span style="font-family:Verdana;"> </span><span style="font-family:Verdana;">10 mm stems (medium matured), hence found to be less stiff. Moisture regain ability showed that canola fibers isolated from ≥8 mm stem diameter were more hydrophobic whereas contact angle measurement showed relatively more hydrophobic nature of 7</span><span style="font-family:Verdana;"> </span><span style="font-family:Verdana;">-</span><span style="font-family:Verdana;"> </span><span style="font-family:Verdana;">10 mm stem fibers. Therefore, this study provided an insightful understanding of the quality of the canola fibers of different stems which will ultimately help to choose the best stem to extract different qualities of fibers for commercial uses.</span>展开更多
Chemical softener (Cepreton UN) is used to soften the cellulosic fiber (cotton) in the textile industries to make clothes better to touch. Therefore, this study investigated the effects of Cepreton UN on both physical...Chemical softener (Cepreton UN) is used to soften the cellulosic fiber (cotton) in the textile industries to make clothes better to touch. Therefore, this study investigated the effects of Cepreton UN on both physical (length, aspect ratio, contact angle, and moisture regain) and mechanical (load at break, elongation at break, tensile stress, young’s modulus, and tenacity) properties of the lignocellulosic canola (HYREAR 3) fibers extracted from narrow, medium, and wide stems. ANOVA showed that fiber diameter had strong effects on elongation at break, load at break, tensile stress, young’s modulus, and aspect ratio for all fibers. Corrgram values showed that tensile stress, young’s modulus, and aspect ratio were negatively correlated to fiber diameter whereas load at break and tenacity were mostly positively correlated to fiber diameter. The fibers were treated with 2% and 10% Cepreton UN and compared with control fibers. In most cases, the fiber diameter was decreased in both 2% and 10% treated medium stem fibers. The mean values of elongation at break, load at break, tenacity, and contact angle were decreased for 10% and increased for 2% and the mean values of tensile stress, young’s modulus, and aspect ratio were decreased for 2% and increased for 10% treated medium stem fibers. Moisture regain (%) mostly decreased for 2%, and increased for 10% treated fibers. Low pH (4.5) had an almost similar effect on fibers as 2% Cepreton UN. Overall, 2% Cepreton UN treatment is found to be better than 10% to make canola fibers less stiff and low pH was found to be an alternative softener treatment strategy.展开更多
The thermo-oxidative aging behaviors of Nylon 1010 films were studied by various analytical methods,such as measuring the chromaticity,relative viscosity,carbonyl index,UV absorbance at 280 nm and elongation at break ...The thermo-oxidative aging behaviors of Nylon 1010 films were studied by various analytical methods,such as measuring the chromaticity,relative viscosity,carbonyl index,UV absorbance at 280 nm and elongation at break of the aged films.The thermo-oxidative aging plots of the results obtained via these various methods at different temperatures are subjected to the time-temperature superposition analysis,which are found to be well superposed.The b＊ values are used as X axis and the other results,i.e.,relative viscosity,carbonyl index,UV absorbance at 280 nm and elongation at break,are used as V axis,respectively.The relationship between the b values and the other results is obtained,from which we can derive the changes of physical and chemical properties at different b＊ values.Since the b＊ values can be quickly determined by using a portable spectrophotometer,the on-line evaluation of the thermo-oxidative aging of Nylon 1010 can be realized.展开更多
文摘In this paper,the relation between the tensile strength,breaking elongationand the Crystallinity,Orientation of silk was studied,which obtalned from thecocoons with different silk worm races,sexes,cocooning conditions.The Crystallinity and degree of Crystal Orientation of fibroin were determinedby the X-ray diffraction.and the birefringence of fibroin was measured withInterference microscope.The research showed that the dependence of strength and elongation of rawsilk on Its crystailinity was not so closed.Although there was linear correlation ofstrength with the birefringence and the degree of crystal orientation of fibroin.But the correlation coefficient of the former was larger than the latter.Therefore,adopting birefringence method which would reflected the degree of orlentation ofboth the amorphous and crystalline region of fibroln was suitable for consideringthe strength.The correlation coefficients of strength and elongation withbirefringence were 0.96 and 0.77 respectively.The latter one was
基金Funded by the Science Technology Project of the National"TenthFive year plan"of China(No.2001BA501A04)
文摘Films were developed from the modified wheat glutens by microbial transglutamina se(MTGase, [E/S]=10u/g,15u/g and 20u/g) in order to improve physical and barri er properties of the films.Glycerol was used as a plasticizer.The films prepared from the modified-glutens by MTGase show a lower elongation at break(E) and a water vapor permeability(WVP), and a higher tensile strength(TS) than the nati ve gluten films.When the modified gluten films by different concentrations of MT Gase are immersed in water at 25℃,their weight losses decreased significantly, and their water resistance increases obviously as expected, compared with the c ontrol gluten films. Moreover, an addition of glycerol as plasticizer greatly mo dified water vapor barrier and mechanical properties of the films.
文摘Many properties of polyester filaments such as heat shrinkage, tenacity, elongation at break and etc. are greatly influenced by drawing, so post-drawing is important in downstream processing. As more and more profile fibers and multi-variance fibers used in textile industry, the properties of above two kinds of differential polyester filaments after drawing in different heat conditions were studied. Finally following conclusions were obtained: Firstly, the tenacity and elongation at break decreases with the rise of Tp. Secondly, the tenacity rises but the elongation at break decreases with the increase of Tb. Then, when the Tb is low, both the shrinkage in boiling water and hi hot air decreases with the rise of Tp, while, when the Tb is high, both the shrinkage rises with the rise of Tp. The last, both the shrinkage decreases with the rise of Tb.
文摘Films were made from the wheat glutens treated with 5%,10%,15%,20%,25% and 30%(wt% of gluten) of sodium dodecyl sulfite (SDS) in order to improve the properties of the films. Glycerol was used as a plasticizer.An addition of SDS in wheat glutens prior to forming films significantly increased the elongation at break(E) (P<0.05) and reduced notably the water vapor permeability(WVP) (P<0.05). In contrast,a decrease in the tensile strength(TS) of the films from gluten containing-SDS was found.Moreover,a significant decrease in P_(O_2) and P_(CO_2) of films from gluten treated with SDS was noticed. Although SDS-treated gluten film was slightly more yellow and darker than control one, it was not visually detrimental. It is indicated that the treatment with SDS prior to forming films greatly enhances the mechanical properties of wheat gluten films.The obivous improvement in water vapor permeability and extensibility of gluten films means that the use of SDS is a potential choice for improving properties of gluten films. The edible film was used to preserve tomatoes. The experimental results show that the shelf life of tomatoes coated with the edible film is extended, and the nutritional quality is kept well.
基金supported by the National Natural Science Foundation of China (Grant No.60472102)the Innovative Program of Shanghai Municipal Education Commission (Grant No.07ZZ03)
文摘High frequency ultrasonic nondestructive testing was conducted using a direct contact method for SUS306 stainless steel treated by high temperature and fracture tensile tests. Reflected ultrasonic echoes were analyzed. The relationships between the ultrasonic attenuation coefficient, strength of backscattering wave and the elongation at break of the samples were obtained. The damages were evaluated by using these results together with the analysis of microstructure and mechanics of the tested material.
文摘A matured canola plant has different types of stems based on the diameter, such as narrow (immature), medium (mature), and wide (over mature). Therefore, t<span style="font-family:Verdana;">his study was focused on investigating the properties of the extracted canola (HYREAR 3) fibers from 3 different diameter of stems (narrow, medium and wide). The physical (average length, aspect ratio, contact angle, and moisture regain) and mechanical (load at break, elongation at break, tensile stress, young’s modulus, and tenacity) properties of fibers were measured. ANOVA showed that stem diameter had effects on all fiber properties except for average length and elongation at break. Fiber diameter also had significant effects on load at break, elongation at break, aspect ratio, tensile stress, and young’s modulus. In corrgram, it was found that tensile stress, young’s modulus, and aspect ratio were negatively correlated to fiber diameter whereas load at break and tenacity were positively associated. Mean values showed that stem diameter had effects on all fiber properties except for average length. The mean values of fiber diameter, load at break, elongation at break, tenacity, and contact angle were highest and the lowest mean values were observed for tensile stress, young’s modulus and aspect ratio in fibers of 7</span><span style="font-family:Verdana;"> </span><span style="font-family:Verdana;">-</span><span style="font-family:Verdana;"> </span><span style="font-family:Verdana;">10 mm stems (medium matured), hence found to be less stiff. Moisture regain ability showed that canola fibers isolated from ≥8 mm stem diameter were more hydrophobic whereas contact angle measurement showed relatively more hydrophobic nature of 7</span><span style="font-family:Verdana;"> </span><span style="font-family:Verdana;">-</span><span style="font-family:Verdana;"> </span><span style="font-family:Verdana;">10 mm stem fibers. Therefore, this study provided an insightful understanding of the quality of the canola fibers of different stems which will ultimately help to choose the best stem to extract different qualities of fibers for commercial uses.</span>
文摘Chemical softener (Cepreton UN) is used to soften the cellulosic fiber (cotton) in the textile industries to make clothes better to touch. Therefore, this study investigated the effects of Cepreton UN on both physical (length, aspect ratio, contact angle, and moisture regain) and mechanical (load at break, elongation at break, tensile stress, young’s modulus, and tenacity) properties of the lignocellulosic canola (HYREAR 3) fibers extracted from narrow, medium, and wide stems. ANOVA showed that fiber diameter had strong effects on elongation at break, load at break, tensile stress, young’s modulus, and aspect ratio for all fibers. Corrgram values showed that tensile stress, young’s modulus, and aspect ratio were negatively correlated to fiber diameter whereas load at break and tenacity were mostly positively correlated to fiber diameter. The fibers were treated with 2% and 10% Cepreton UN and compared with control fibers. In most cases, the fiber diameter was decreased in both 2% and 10% treated medium stem fibers. The mean values of elongation at break, load at break, tenacity, and contact angle were decreased for 10% and increased for 2% and the mean values of tensile stress, young’s modulus, and aspect ratio were decreased for 2% and increased for 10% treated medium stem fibers. Moisture regain (%) mostly decreased for 2%, and increased for 10% treated fibers. Low pH (4.5) had an almost similar effect on fibers as 2% Cepreton UN. Overall, 2% Cepreton UN treatment is found to be better than 10% to make canola fibers less stiff and low pH was found to be an alternative softener treatment strategy.
文摘The thermo-oxidative aging behaviors of Nylon 1010 films were studied by various analytical methods,such as measuring the chromaticity,relative viscosity,carbonyl index,UV absorbance at 280 nm and elongation at break of the aged films.The thermo-oxidative aging plots of the results obtained via these various methods at different temperatures are subjected to the time-temperature superposition analysis,which are found to be well superposed.The b＊ values are used as X axis and the other results,i.e.,relative viscosity,carbonyl index,UV absorbance at 280 nm and elongation at break,are used as V axis,respectively.The relationship between the b values and the other results is obtained,from which we can derive the changes of physical and chemical properties at different b＊ values.Since the b＊ values can be quickly determined by using a portable spectrophotometer,the on-line evaluation of the thermo-oxidative aging of Nylon 1010 can be realized.
