The outbreak of coronavirus has led to an increase in the demand for facemasks globally. Unavailability of appropriate polypropylene non-woven fabrics face masks as a result of inadequate supply to satisfy the growing...The outbreak of coronavirus has led to an increase in the demand for facemasks globally. Unavailability of appropriate polypropylene non-woven fabrics face masks as a result of inadequate supply to satisfy the growing population has brought about the manufacturing of locally fabrics masks to augment or substitute standard medical class facemasks. The study aims at analyzing airflow of these locally manufactured fabrics to determine possible means of transmitting the virus as well as establish comfort of the user of these masks. Standard polypropylene non-woven, woven and knitted fabrics were considered for the study. Air permeability test was conducted on these fabrics using Frazier Air permeability tester. Depending on the property significant variation in the textile fabrics, polypropylene non-woven is widely accepted for facial masks. Nevertheless, this study illustrates that woven and knitted fabrics have more open structures, which allow a high rate of air penetration and so may require two or three layers to prevent antimicrobial or antiviral potential.展开更多
Nano-silver and waterborne polyurethane(WPU)composite emulsion was synthesized.The average diameter of silver nanoparticles(SNPs)was about 20 nm,and the average diameter of WPU was 101.32 nm.The anti-bacteria finishin...Nano-silver and waterborne polyurethane(WPU)composite emulsion was synthesized.The average diameter of silver nanoparticles(SNPs)was about 20 nm,and the average diameter of WPU was 101.32 nm.The anti-bacteria finishing of a polypropylene non-woven fabric(NWF)was carried out by ultraviolet finishing technology and the double dipping twin-roll method.The standard AATCC100 was used to test the antimicrobial activity of the samples.The results showed that the antimicrobial rates of Klebsiella pneumoniae(K.pneumoniae)and Staphylococcus aureus(S.aureus)were above 90%,which indicated that the NWF finishing had good antimicrobial activity.In addition,the thermal stability,mechanical properties,whiteness and contact angle of antimicrobial finishing nonwovens were characterized.The results showed that the performance of antimicrobial nonwovens was stable at 300℃.The breaking strength was better than that of untreated nonwovens,and the contact angle reached 119.1°.展开更多
Based on the processing experiment and sodium flame test this paper deals with the relationship between processing parameters, structure, and filtration property of melt blown fabric. Through the image analysis of Que...Based on the processing experiment and sodium flame test this paper deals with the relationship between processing parameters, structure, and filtration property of melt blown fabric. Through the image analysis of Questar micro-images in combination with the SEM observation and the measurement of some macrostructure indices, the relationship between the processing parameters and the structure especially the microstructure is emphasized Finally the effect of somestructure factors on filtration properties is discussed theoretically.展开更多
In previous research much effort has been devoted to the geometry of woven fabrics and relat-ed problems under the assumption of constant yarn configuration in fabric.This paper will first re-port that image crimp (ya...In previous research much effort has been devoted to the geometry of woven fabrics and relat-ed problems under the assumption of constant yarn configuration in fabric.This paper will first re-port that image crimp (yarn crimp measured by an image analysis method) seems larger than actualvalue.From the explanation of this result,the variation of yarn configuration in woven fabric dueto the non-uniform flattening is revealed.The significance of this actual structure of woven fabricsis discussed.It is believed that the variation of yarn configuration is very important for fabric per-formance,and may be an advantage for fabric quality.展开更多
In this paper,the failure features of strip tensile specimen were observed and analysed for need-le-punched non-woven geotextiles.A mechanical model which expresses the relation between thetensile modulus,the strip sp...In this paper,the failure features of strip tensile specimen were observed and analysed for need-le-punched non-woven geotextiles.A mechanical model which expresses the relation between thetensile modulus,the strip specimen size,contraction factor and the tensile strength of non-wovenfabric was derived.The theoretical prediction showed that the main factor influencing tensilestrength of non-woven geotextile specimens with different size is the contraction factor of specimenor the specimen aspect ratio(width/length).The larger the aspect ratio,the higher the tensilestrength test value of geotextiles,but the experiments showed that the specimen tensile strength isnot increased with increasing the width of specimen.The reason was discussed and it seemed thatthe deviation could be served as an indication of the degree of imperfectness of the non-wovenstructure.展开更多
The article reveals the development and analysis of fabric structure for its moisture absorbency property and its application in Civil engineering for curing of concrete. The presence of moisture in concrete and time ...The article reveals the development and analysis of fabric structure for its moisture absorbency property and its application in Civil engineering for curing of concrete. The presence of moisture in concrete and time of curing are the major influencing factors for concrete strength. Normal practice of curing is to wrap the concrete with jute woven fabric and spraying of water. The absorbency characteristics of different GSM (Gram per square meter) of woven and Non-woven fabric were studied. The Non-woven fabric absorbency is superior to woven fabric of same GSM by its three dimensional structure and high pore volume. The strength of concrete cured with Non- woven fabric is 2.1 N/mm2 higher than woven fabric of same 350 GSM. The difference in compressive strength of Non-woven fabric of 350 GSM and 750 GSM is 0.06 N/mm2 which is marginal.展开更多
为探明露场叠盘暗化出苗(darkened emergence by stacked plates in open space,DE)与无纺布覆盖(seedling mulched with non-woven fabric,NM)协同育秧对机插杂交籼稻成苗特性的影响,该研究于2020—2021年在不同气候条件下以杂交籼稻...为探明露场叠盘暗化出苗(darkened emergence by stacked plates in open space,DE)与无纺布覆盖(seedling mulched with non-woven fabric,NM)协同育秧对机插杂交籼稻成苗特性的影响,该研究于2020—2021年在不同气候条件下以杂交籼稻天优华占为材料,以摆盘出苗(swing-plate emergence,SE)和薄膜覆盖(seedling mulched with film,FM)为对照进行试验,探究DE与NM对出苗微环境与出苗特征以及秧苗素质的影响,并验证其机插适应性。结果表明:1)相对于外界环境,DE提高了出苗微环境的平均温度与平均相对湿度。与SE相比,DE降低了温度与相对湿度变异系数,缩短了种子出苗时间,并大幅提高出苗率与出苗整齐度;较FM,NM改善了秧床微环境,促进秧苗均衡生长;DE+NM有效提高成苗整齐度与成苗率,2 a间成苗整齐度较DE+FM、SE+NM与SE+FM分别增加了7.22~8.91、3.67~5.55和8.29~10.38个百分点(P<0.05),2 a间成苗率分别提高了4.08~8.09、11.79~14.88和20.10~40.02个百分点(除2021年DE+FM外,P<0.05)。2)DE的成苗密度显著优于SE(P<0.05),进而增加了单位面积的总根长、白根数、根表面积,及根系盘结力;与FM相比,NM显著增大了单位面积根体积(P<0.05);DE+NM增加了单位面积的根体积、根表面积、根生物量,同时提高了根系盘结力(除2020年DE+FM外)。3)较其他3种育秧处理,DE+NM显著降低漏插率与伤秧率(P<0.05),提高3~4苗/穴比例,并增加了每穴苗数。综上所述,DE+NM通过改善育秧环境实现了培育壮秧,秧苗机插效果好,所育秧苗呈现出“齐苗、壮根、宜机插”特性。该育秧技术有效解决了四川稻区传统机插育秧存在的秧苗生长不齐、盘根弱、机插效果差等问题,并兼具低成本、耐粗放、高效低碳等特点。研究结果可为本区域机插壮秧培育和水稻丰产增效栽培提供理论与技术支撑。展开更多
文摘The outbreak of coronavirus has led to an increase in the demand for facemasks globally. Unavailability of appropriate polypropylene non-woven fabrics face masks as a result of inadequate supply to satisfy the growing population has brought about the manufacturing of locally fabrics masks to augment or substitute standard medical class facemasks. The study aims at analyzing airflow of these locally manufactured fabrics to determine possible means of transmitting the virus as well as establish comfort of the user of these masks. Standard polypropylene non-woven, woven and knitted fabrics were considered for the study. Air permeability test was conducted on these fabrics using Frazier Air permeability tester. Depending on the property significant variation in the textile fabrics, polypropylene non-woven is widely accepted for facial masks. Nevertheless, this study illustrates that woven and knitted fabrics have more open structures, which allow a high rate of air penetration and so may require two or three layers to prevent antimicrobial or antiviral potential.
基金National Natural Science Foundation of China(Regional Fund)(No.51863020)
文摘Nano-silver and waterborne polyurethane(WPU)composite emulsion was synthesized.The average diameter of silver nanoparticles(SNPs)was about 20 nm,and the average diameter of WPU was 101.32 nm.The anti-bacteria finishing of a polypropylene non-woven fabric(NWF)was carried out by ultraviolet finishing technology and the double dipping twin-roll method.The standard AATCC100 was used to test the antimicrobial activity of the samples.The results showed that the antimicrobial rates of Klebsiella pneumoniae(K.pneumoniae)and Staphylococcus aureus(S.aureus)were above 90%,which indicated that the NWF finishing had good antimicrobial activity.In addition,the thermal stability,mechanical properties,whiteness and contact angle of antimicrobial finishing nonwovens were characterized.The results showed that the performance of antimicrobial nonwovens was stable at 300℃.The breaking strength was better than that of untreated nonwovens,and the contact angle reached 119.1°.
文摘Based on the processing experiment and sodium flame test this paper deals with the relationship between processing parameters, structure, and filtration property of melt blown fabric. Through the image analysis of Questar micro-images in combination with the SEM observation and the measurement of some macrostructure indices, the relationship between the processing parameters and the structure especially the microstructure is emphasized Finally the effect of somestructure factors on filtration properties is discussed theoretically.
文摘In previous research much effort has been devoted to the geometry of woven fabrics and relat-ed problems under the assumption of constant yarn configuration in fabric.This paper will first re-port that image crimp (yarn crimp measured by an image analysis method) seems larger than actualvalue.From the explanation of this result,the variation of yarn configuration in woven fabric dueto the non-uniform flattening is revealed.The significance of this actual structure of woven fabricsis discussed.It is believed that the variation of yarn configuration is very important for fabric per-formance,and may be an advantage for fabric quality.
文摘In this paper,the failure features of strip tensile specimen were observed and analysed for need-le-punched non-woven geotextiles.A mechanical model which expresses the relation between thetensile modulus,the strip specimen size,contraction factor and the tensile strength of non-wovenfabric was derived.The theoretical prediction showed that the main factor influencing tensilestrength of non-woven geotextile specimens with different size is the contraction factor of specimenor the specimen aspect ratio(width/length).The larger the aspect ratio,the higher the tensilestrength test value of geotextiles,but the experiments showed that the specimen tensile strength isnot increased with increasing the width of specimen.The reason was discussed and it seemed thatthe deviation could be served as an indication of the degree of imperfectness of the non-wovenstructure.
文摘The article reveals the development and analysis of fabric structure for its moisture absorbency property and its application in Civil engineering for curing of concrete. The presence of moisture in concrete and time of curing are the major influencing factors for concrete strength. Normal practice of curing is to wrap the concrete with jute woven fabric and spraying of water. The absorbency characteristics of different GSM (Gram per square meter) of woven and Non-woven fabric were studied. The Non-woven fabric absorbency is superior to woven fabric of same GSM by its three dimensional structure and high pore volume. The strength of concrete cured with Non- woven fabric is 2.1 N/mm2 higher than woven fabric of same 350 GSM. The difference in compressive strength of Non-woven fabric of 350 GSM and 750 GSM is 0.06 N/mm2 which is marginal.
文摘为探明露场叠盘暗化出苗(darkened emergence by stacked plates in open space,DE)与无纺布覆盖(seedling mulched with non-woven fabric,NM)协同育秧对机插杂交籼稻成苗特性的影响,该研究于2020—2021年在不同气候条件下以杂交籼稻天优华占为材料,以摆盘出苗(swing-plate emergence,SE)和薄膜覆盖(seedling mulched with film,FM)为对照进行试验,探究DE与NM对出苗微环境与出苗特征以及秧苗素质的影响,并验证其机插适应性。结果表明:1)相对于外界环境,DE提高了出苗微环境的平均温度与平均相对湿度。与SE相比,DE降低了温度与相对湿度变异系数,缩短了种子出苗时间,并大幅提高出苗率与出苗整齐度;较FM,NM改善了秧床微环境,促进秧苗均衡生长;DE+NM有效提高成苗整齐度与成苗率,2 a间成苗整齐度较DE+FM、SE+NM与SE+FM分别增加了7.22~8.91、3.67~5.55和8.29~10.38个百分点(P<0.05),2 a间成苗率分别提高了4.08~8.09、11.79~14.88和20.10~40.02个百分点(除2021年DE+FM外,P<0.05)。2)DE的成苗密度显著优于SE(P<0.05),进而增加了单位面积的总根长、白根数、根表面积,及根系盘结力;与FM相比,NM显著增大了单位面积根体积(P<0.05);DE+NM增加了单位面积的根体积、根表面积、根生物量,同时提高了根系盘结力(除2020年DE+FM外)。3)较其他3种育秧处理,DE+NM显著降低漏插率与伤秧率(P<0.05),提高3~4苗/穴比例,并增加了每穴苗数。综上所述,DE+NM通过改善育秧环境实现了培育壮秧,秧苗机插效果好,所育秧苗呈现出“齐苗、壮根、宜机插”特性。该育秧技术有效解决了四川稻区传统机插育秧存在的秧苗生长不齐、盘根弱、机插效果差等问题,并兼具低成本、耐粗放、高效低碳等特点。研究结果可为本区域机插壮秧培育和水稻丰产增效栽培提供理论与技术支撑。
