The phenomenon of a material failure varies with its gauge length in use. In the present study,the breaking strengths of J30/C70 and J55/C45 blended yarns spun by the ring spinning technology were investigated with th...The phenomenon of a material failure varies with its gauge length in use. In the present study,the breaking strengths of J30/C70 and J55/C45 blended yarns spun by the ring spinning technology were investigated with the employment of the equations derived from the Weibull theory. The four probability estimators of the Weibull distribution were also evaluated. The results showed that the estimator (2a) was acceptable for calculating the Weibull modulus of the jute/cotton blended yarns. With the exception of breaking strength of the J30/C70 at the gauge length of 200 mm, the breaking strengths of both blended yarn could be predicted accurately by the Eqs.(9) or (10) in this paper.展开更多
The feasibility of combination process of jute degumming and bleaching with alkali-hydrogen peroxide in one-step-one-bath was discussed. The combination process basically has the similar function as the traditional tw...The feasibility of combination process of jute degumming and bleaching with alkali-hydrogen peroxide in one-step-one-bath was discussed. The combination process basically has the similar function as the traditional two-step-two-bath method. The factors such as hydrogen peroxide concentration, CBI concentration, sodium hydroxide concentration, treatment time and temperature were studied respectively, and then an orthogonal experiment was designed to study the interactions among the hydrogen peroxide concentration, CBI concentration, sodium hydroxide concentration. After the designed experiments, the optimum treatment conditions were obtained as follows: hydrogen peroxide of 12g/L, sodium hydroxide of 4g/L, CBI of 4g/L, JFC of 1g/L, treatment time of 60min and temperature of 75℃.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
Cellulose pulps were directly dissolved in a green solvent of sodium hydrate/urea/thiourea/water with different composition for the purpose to prepare new regenerated cellulose fibers or films. The results showed that...Cellulose pulps were directly dissolved in a green solvent of sodium hydrate/urea/thiourea/water with different composition for the purpose to prepare new regenerated cellulose fibers or films. The results showed that the highest solubility of cellulose in the solvent with the composition of 8/8/6.5/77.5. The results revealed that the pulp feeding sequence, stirring rate, pre-treatment of pulp and pulp size affected the cellulose concentration in the green solvent. Accordingly, the more effective dissolution method was proposed in order to get higher concentration of cellulose. Furthermore, the properties of solution prepared by different kinds of pulps in the solvent were investigated by ARES rheometer. Rheological analyses indicated that all cellulose aqueous solutions in their high concentration were pseudoplastic fluids and sensitive to temperature and tended to transform to gel when temperature increased.展开更多
Jute fibre properties,viz. linear density,mechanical properties,and fibre staple length were analyzed in this paper. Morphology,lignin content,and composition analysis for jute fibres were investigated in order to giv...Jute fibre properties,viz. linear density,mechanical properties,and fibre staple length were analyzed in this paper. Morphology,lignin content,and composition analysis for jute fibres were investigated in order to give further understanding of the fibre properties changing during the chemical treatment and yarn producing processes. The results show that jute properties are greatly changed during the processes of chemical treatment,breaking carding,and finisher carding,whereas slight changes can be found in the processes of drawing,roving,and spinning.展开更多
Novel derivatives containing bi-perfluorooctane-sulfonamide group were designed and synthesized.The 19FNMR,FTIR were used to characterize derivatives structures.The compounds were applied to paper for oil-repellency.T...Novel derivatives containing bi-perfluorooctane-sulfonamide group were designed and synthesized.The 19FNMR,FTIR were used to characterize derivatives structures.The compounds were applied to paper for oil-repellency.The results show that treated paper had excellent oil-repellency at very low concentration of bi-perfluorooctane-sulfonamide derivatives.When novel compounds,polyvinyl alcohol(PVA)and oxidized starch were applied together as coat sizing,the oxidized starch and PVA did not affect the oil repellency properties of paper.展开更多
The mechanism of filament pre-tension is put forward. The effect of filament pre-tension on Sirofil composite yarn properties, such as hairiness and structural stability, are theoretically and experimentally studied. ...The mechanism of filament pre-tension is put forward. The effect of filament pre-tension on Sirofil composite yarn properties, such as hairiness and structural stability, are theoretically and experimentally studied. The theoretical analysis agrees well with the experimental results. The present theory shows that suitable choice of filament pre-tension can enormously reduce hairiness and improve structural stability of Sirofil composite yarn.展开更多
A microscope method was developed for testing the blending ratio of akund/cotton blended yarns. Fiber characteristics such as diameter, longitudinal feature, and hollow structure were observed to identify akund and co...A microscope method was developed for testing the blending ratio of akund/cotton blended yarns. Fiber characteristics such as diameter, longitudinal feature, and hollow structure were observed to identify akund and cotton. Therefore, the measurement of the blending ratio for akund/cotton blended yarns based on each fiber's amount, moisture regain, and metric count was available. The results show that using specimen's longitudinal section is more effective during the fiber counting than specimen's transverse section benefiting from the separation of the fibers.展开更多
Cellulose,being as the most abundant nature polymer material and the most promising oil substitute,attracts more and more interests.A new cellulose dissolution system,phosphoric acid(PA)/polyphosphoric acid(PPA) solve...Cellulose,being as the most abundant nature polymer material and the most promising oil substitute,attracts more and more interests.A new cellulose dissolution system,phosphoric acid(PA)/polyphosphoric acid(PPA) solvent,was investigated in this study.It had been found that a larger cellulose solid content could be dissolved quickly in a hypothermic situation.By evaluating the stability of regenerated cellulose film and the formation of anisotropic solution,the dissolution behavior of cellulose was investigated.Wide-angle X-ray diffraction(WAXD) and Fourier transform infrared spectroscopy(FT-IR) were employed to characterize the crystalline structure and morphology of regenerated cellulose.The measurement results revealed a transition from cellulose-Ⅰ of raw cellulose to cellulose-Ⅱ of regenerated cellulose and a decrease of crystallinity of cellulose after dissolved.This was attributed to the interaction between cellulose and acid solvent,which leaded to the breakage of cellulose intra-and inter-molecule hydrogen bonds and the conformation change of cellulose C6-OH.Moreover,the formation process of cellulose liquid crystal solution was illustrated by polarized light microscope(PLM).That may be induced by the rearranging movement of the cellulose macromolecular chains.展开更多
A novel machine learning method, gene expression programming(GEP), was employed to build quatitative structure-activity relationship(QSAR) models for predicting the enhancement effect of nitroimidazole compounds o...A novel machine learning method, gene expression programming(GEP), was employed to build quatitative structure-activity relationship(QSAR) models for predicting the enhancement effect of nitroimidazole compounds on irradiation. The models were based on descriptors which were calculated from the molecular structures. Four descriptors were selected from the pool of descriptors by best multiple linear regression(BMLR) method. After that, three regression methods, multiple linear regression(MLR), support vector machine(SVM) and GEP, were used to build QSAR models. Compared to MLR and SVM, GEP produced a better model with the square of correlation coefficient(R2), 0.9203 and 0.9014, and the root mean square error(RMSE), 0.6187 and 0.6875, for training set and test set, respectively. The results show that the GEP model has better predictive ability and more reliable than the MLR and SVM models. This indicates that GEP is a promising method on relevant researches in radiation area.展开更多
基金National Key Technologies R&D Programof China (No.2007BAE41B01)
文摘The phenomenon of a material failure varies with its gauge length in use. In the present study,the breaking strengths of J30/C70 and J55/C45 blended yarns spun by the ring spinning technology were investigated with the employment of the equations derived from the Weibull theory. The four probability estimators of the Weibull distribution were also evaluated. The results showed that the estimator (2a) was acceptable for calculating the Weibull modulus of the jute/cotton blended yarns. With the exception of breaking strength of the J30/C70 at the gauge length of 200 mm, the breaking strengths of both blended yarn could be predicted accurately by the Eqs.(9) or (10) in this paper.
文摘The feasibility of combination process of jute degumming and bleaching with alkali-hydrogen peroxide in one-step-one-bath was discussed. The combination process basically has the similar function as the traditional two-step-two-bath method. The factors such as hydrogen peroxide concentration, CBI concentration, sodium hydroxide concentration, treatment time and temperature were studied respectively, and then an orthogonal experiment was designed to study the interactions among the hydrogen peroxide concentration, CBI concentration, sodium hydroxide concentration. After the designed experiments, the optimum treatment conditions were obtained as follows: hydrogen peroxide of 12g/L, sodium hydroxide of 4g/L, CBI of 4g/L, JFC of 1g/L, treatment time of 60min and temperature of 75℃.
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Cellulose pulps were directly dissolved in a green solvent of sodium hydrate/urea/thiourea/water with different composition for the purpose to prepare new regenerated cellulose fibers or films. The results showed that the highest solubility of cellulose in the solvent with the composition of 8/8/6.5/77.5. The results revealed that the pulp feeding sequence, stirring rate, pre-treatment of pulp and pulp size affected the cellulose concentration in the green solvent. Accordingly, the more effective dissolution method was proposed in order to get higher concentration of cellulose. Furthermore, the properties of solution prepared by different kinds of pulps in the solvent were investigated by ARES rheometer. Rheological analyses indicated that all cellulose aqueous solutions in their high concentration were pseudoplastic fluids and sensitive to temperature and tended to transform to gel when temperature increased.
基金National Key Technologies R&D Program of China (No.2007BAE41B01)
文摘Jute fibre properties,viz. linear density,mechanical properties,and fibre staple length were analyzed in this paper. Morphology,lignin content,and composition analysis for jute fibres were investigated in order to give further understanding of the fibre properties changing during the chemical treatment and yarn producing processes. The results show that jute properties are greatly changed during the processes of chemical treatment,breaking carding,and finisher carding,whereas slight changes can be found in the processes of drawing,roving,and spinning.
文摘Novel derivatives containing bi-perfluorooctane-sulfonamide group were designed and synthesized.The 19FNMR,FTIR were used to characterize derivatives structures.The compounds were applied to paper for oil-repellency.The results show that treated paper had excellent oil-repellency at very low concentration of bi-perfluorooctane-sulfonamide derivatives.When novel compounds,polyvinyl alcohol(PVA)and oxidized starch were applied together as coat sizing,the oxidized starch and PVA did not affect the oil repellency properties of paper.
基金National Natural Science Foundation of China (No.10572038)the Program for New Century Excellent Talents in University .
文摘The mechanism of filament pre-tension is put forward. The effect of filament pre-tension on Sirofil composite yarn properties, such as hairiness and structural stability, are theoretically and experimentally studied. The theoretical analysis agrees well with the experimental results. The present theory shows that suitable choice of filament pre-tension can enormously reduce hairiness and improve structural stability of Sirofil composite yarn.
文摘A microscope method was developed for testing the blending ratio of akund/cotton blended yarns. Fiber characteristics such as diameter, longitudinal feature, and hollow structure were observed to identify akund and cotton. Therefore, the measurement of the blending ratio for akund/cotton blended yarns based on each fiber's amount, moisture regain, and metric count was available. The results show that using specimen's longitudinal section is more effective during the fiber counting than specimen's transverse section benefiting from the separation of the fibers.
文摘Cellulose,being as the most abundant nature polymer material and the most promising oil substitute,attracts more and more interests.A new cellulose dissolution system,phosphoric acid(PA)/polyphosphoric acid(PPA) solvent,was investigated in this study.It had been found that a larger cellulose solid content could be dissolved quickly in a hypothermic situation.By evaluating the stability of regenerated cellulose film and the formation of anisotropic solution,the dissolution behavior of cellulose was investigated.Wide-angle X-ray diffraction(WAXD) and Fourier transform infrared spectroscopy(FT-IR) were employed to characterize the crystalline structure and morphology of regenerated cellulose.The measurement results revealed a transition from cellulose-Ⅰ of raw cellulose to cellulose-Ⅱ of regenerated cellulose and a decrease of crystallinity of cellulose after dissolved.This was attributed to the interaction between cellulose and acid solvent,which leaded to the breakage of cellulose intra-and inter-molecule hydrogen bonds and the conformation change of cellulose C6-OH.Moreover,the formation process of cellulose liquid crystal solution was illustrated by polarized light microscope(PLM).That may be induced by the rearranging movement of the cellulose macromolecular chains.
基金Supported by the National Natural Science Foundation of China(No.81202153), the Research Fund for Youth Scholars of Union Medical College of China(No.2012D03), the Research Fund for the Doctoral Program of Higher Education of China (No.20121106120042) and the Development Fund of Institute of Radiation Medicine, Chinese Academy of Medical Sciences (No.SF1227).
文摘A novel machine learning method, gene expression programming(GEP), was employed to build quatitative structure-activity relationship(QSAR) models for predicting the enhancement effect of nitroimidazole compounds on irradiation. The models were based on descriptors which were calculated from the molecular structures. Four descriptors were selected from the pool of descriptors by best multiple linear regression(BMLR) method. After that, three regression methods, multiple linear regression(MLR), support vector machine(SVM) and GEP, were used to build QSAR models. Compared to MLR and SVM, GEP produced a better model with the square of correlation coefficient(R2), 0.9203 and 0.9014, and the root mean square error(RMSE), 0.6187 and 0.6875, for training set and test set, respectively. The results show that the GEP model has better predictive ability and more reliable than the MLR and SVM models. This indicates that GEP is a promising method on relevant researches in radiation area.