Comparative Study of Polypropylene Non-Woven Surgical Mask and Locally Manufactured Woven and Knitted Fabrics Facial Masks

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.

A Cell-Based Smoothed Finite Element Method for Modal Analysis of Non-Woven Fabrics

The combination of a 4-node quadrilateral mixed interpolation of tensorial components element(MITC4)and the cell-based smoothed finite element method(CSFEM)was formulated and implemented in this work for the analysis of free vibration and unidirectional buckling of shell structures.This formulation was applied to numerous numerical examples of non-woven fabrics.As CSFEM schemes do not require coordinate transformation,spurious modes and numerical instabilities are prevented using bilinear quadrilateral element subdivided into two,three and four smoothing cells.An improvement of the original CSFEM formulation was made regarding the calculation of outward unit normal vectors,which allowed to remove the integral operator in the strain smoothing operation.This procedure conducted both to the simplification of the developed formulation and the reduction of computational cost.A wide range of values for the thickness-to-length ratio and edge boundary conditions were analysed.The developed numerical model proved to overcome the shear locking phenomenon with success,revealing both reduced implementation effort and computational cost in comparison to the conventional FEM approach.The cell-based strain smoothing technique used in this work yields accurate results and generally attains higher convergence rate in energy at low computational cost.

Preparation of UV-curable Nano-silver Antimicrobial Agent and Its Application in Non-woven Fabric

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°.

Beijing Dayuan Non-woven Fabric Co.Ltd

Situated in the Shilong Industrial District of Mentougou, Beijing, the Beijing Dayuan Non-woven Fabric Co. Ltd is a Sino-foreign joint venture producing non-woven fabrics, set up in 1991.

A STUDY OF THE SPECIMEN SIZE OF STRIP TENSILE TEST FOR NEEDLE-PUNCHED NON-WOVEN GEOTEXTILES

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.

Relationships between the Processing Parameters of Melt Blown Nonwoven Fabric and Its Structure and Filtration Property

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.

Fabric Structure for Moisture Retention Property and Its Application in Civil Engineering

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.

Cost analysis and comparison of plain cotton and disposable non-woven treatment towels

Objective: To choose a reasonably priced and low-cost treatment towel suitable for clinical application of hospital so as to reduce the cost of the hospital and make a reasonable use of resources through the cost analysis and comparison of the plain cotton and disposable non-woven treatment towels. Methods: The cost of the single pack plain cotton towel and disposable non-woven towel were analyzed and at the same time, 49185 packs of plain cotton towels which were the total consumption quantity of our hospital in 2017 and the same quantity of disposable non-woven towers were analyzed in the cost for comparison. Results:A single pack of disposable non-woven towel was RMB 2.50 cheaper than the plain cotton towel and the use of disposable non-woven towel can save the cost of RMB 2.50 per pack. In 2017, 49185 packs of plain cotton towel were used in total, which cost RMB 122962.50 less than the same quantity of disposable non-woven towels and using the disposable non-woven towel could save RMB 122962.50 annually. Conclusion: Compared with the plain cotton towel, the non-woven shares the advantages of none flocculation, longer storage time and better antibacterial effect as well as the material, cleaning and labor costs-saving. The cost of the disposable non-woven treatment towel is lower than that of the reusable plain cotton towel. Therefore, it is recommended to use the disposable non-woven treatment towel.

不同土壤地表处理对坡地果园表层地温变化的影响

通过不同地表处理,研究了夏季坡地果园表层地温变化。结果表明:清耕地表温度过高,甚至最高可以达到近50℃,既就是土壤湿润状态,也会达到30~35℃,高温势必增加水分蒸发,不利于土壤良好水分状态保持;生草覆盖地表温度较低、变化平稳,且对土壤水分蒸发有阻隔作用;园艺地布覆盖,虽能阻挡高温引起的水分散发,但因过于封闭引起地表温度依然较高。综合比较,生草覆盖最利于坡地果园地表适宜地温保持,而且可以适度阻止水分蒸发。

露场叠盘暗化出苗与无纺布覆盖对杂交籼稻成苗特性的影响

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。

滴灌和覆盖条件下山地苹果园土壤蒸发的空间分布

减少土壤蒸发是提高果园水分利用效率的重要途径,覆盖是减少土壤蒸发的有效方式。在黄土高原山地苹果园4个土壤干湿循环周期中,设置3个灌水水平,即高水(85%θ_(f))、中水(70%θ_(f))和不灌水;2种覆盖方式,即园艺地布覆盖和不覆盖。各处理中根据与果树种植行的间距在水平方向设置3个空间点位(点位A,120 cm;点位B,60 cm;点位C,0 cm),研究滴灌与覆盖下果园土壤蒸发的空间分布并分析点位、气象因素和土壤水分情况对土壤蒸发的影响。研究表明:高水和中水处理下,土壤蒸发在空间上呈“单峰型”曲线分布,不灌水处理下水平方向上3个点位的土壤蒸发差异不显著。园艺地布覆盖可有效抑制土壤蒸发。在中水水平下,园艺地布覆盖显著增大了距果树行60 cm点位的土壤水分,土壤蒸发量减少5.26%~27.75%。偏相关分析表明,园艺地布覆盖减弱了点位和环境因素对土壤蒸发的影响,增大了土壤水分对土壤蒸发的影响。本研究推荐处理组合为园艺地布覆盖+中水。

丝胶浸渍棉质非织造地膜的制备与表征

将棉质半成品水刺非织造布浸渍于不同质量分数的废蚕丝制成的丝胶溶液中,通过二浸二轧工艺烘干定型,实现了可降解棉质非织造地膜的制备。通过灰色关联分析得出影响地膜强度的因素及其排序为:回潮率>增重率>丝胶质量分数;采用ESEM、红外光谱、降解率等方法进行理化性能表征,分析其降解前后性能差异。结果表明:浸渍涂层法中胶液质量分数为1%时,其理化性能最佳,纵横向断裂强力分别为33 N、44 N,回潮率为10.8%。

麻/丝非织造布农用地膜的研制和性能分析

塑料地膜在自然界难以降解,越来越多的塑料地膜残留物会给农业生产与生态环境带来危害。采用亚麻和蚕丝纤维的纺织下脚料制备麻/丝非织造布农用地膜,通过正交试验法对其工艺参数进行优化,并对地膜的农用性能进行了测试。结果表明:亚麻与丝的质量比为96∶4,面密度为35 g/m2,黏合剂质量分数为12%时,制成地膜的断裂强力为30 N,厚度为0.114 8 mm,回潮率为6.7%;红外分析显示麻/丝非织造布地膜可完全自然降解;地膜具有较好的保温性和保墒作用,且土壤的含氮量随地膜降解而提高。

浸渍粘合法制备棉丝非织造地膜及其性能表征

通过将棉、丝纤维按不同的配比进行混合,经过梳理、成网、水刺工艺固结定型,然后在4%的明胶溶液中进行浸渍处理,实现可降解棉质非织造地膜的制备。测试该产品的强力、透水性、透湿性、降解性,采用ESEM、红外光谱、降解率等方法进行理化性能表征,分析其降解前后的性能差异。结果表明:该非织造地膜与常规农用地膜相比具有较好的物理性能、降解性,且降解后的土壤全氮含量增加较大,有利于土壤增肥。

浮膜覆盖对地温、气温及蔬菜生长发育的影响

浮膜覆盖是近几年发展起来的一种新型覆盖栽培技术。该研究通过对浮膜覆盖区、薄膜覆盖区以及无覆盖对照区地温、气温的多点连续测量,利用调和解析的方法,分析了浮膜覆盖空间的温度变化特征以及和其它覆盖区的区别,并调查了浮膜覆盖对油菜生长发育的影响。研究结果表明,在北京春季晴天微风的情况下,浮膜覆盖区的白天(6:00～18:00)平均气温比无覆盖区高约7℃,晚间平均气温比无覆盖区高约3℃;从地表面到深度30cm的全天平均地温,浮膜覆盖区比无覆盖区高约2℃。根据调和解析的结果,深度10cm处的地温最大值出现的时间,浮膜覆盖区比无覆盖区晚约30min,薄膜拱棚区比无覆盖区则晚约90min。同样根据调和解析的结果,各区的地温不易层深度有明显差别,薄膜拱棚区为37.2cm,浮膜拱棚区和浮膜直接覆盖区的不易层深度分别为47.2cm和44.1cm,无覆盖区为50.6cm。

无纺布覆盖对烤烟生长发育及产质量的影响

为探讨无纺布在烤烟种植中的应用前景,以云烟97为材料,研究了不同覆盖材料对烟叶农艺性状、产质量的影响。结果表明,覆盖无纺布具有与覆盖地膜同等的促进烟叶生长发育的作用,能够显著提高上等烟比例,增加烟叶的经济效益;覆盖无纺布处理的烟叶外观质量优于覆盖地膜处理,化学成分更趋协调。

园艺地布覆盖对桃园土壤和桃果实品质的影响

为探究园艺地布覆盖对桃园根际土壤理化性质、微生物和果实品质的影响,在江苏省南京地区桃园以不覆盖为对照,研究桃树树盘覆盖地布后土壤环境的变化,利用16SrRNA基因高通量测序对土壤细菌群落进行分析,探究覆盖对土壤微生物的影响。结果表明:覆盖显著提高了0~20cm土层有机质、全磷、全钾及若干微量元素含量,同时显著提高了土壤酸性磷酸酶、脲酶、蔗糖酶和过氧化氢酶活性;地布覆盖处理土壤细菌16S rRNA OTU数显著高于对照,土壤细菌群落丰度显著提高,但均匀度有所降低;变形菌门为覆盖下的优势菌门,γ变形菌纲和α变形菌纲为优势菌纲;从果实品质来看,地布覆盖显著提高了桃单果重、可溶性糖含量和维生素C含量。综上,地布覆盖通过提高土壤酶活性提高了有益菌的种类和数量,并提高了果实品质。

干旱半干旱地区双垄地布覆盖对土壤水分的影响

为探明一种可替代覆盖材料的可行性,在甘肃省定西市安定区开展了为期1 a的监测试验,试验设防草地布加地膜覆垄(MB)、防草地布覆垄(DB)和裸地起垄(CK)3种处理,利用土壤水分、水势传感器分别对沟内地表下5、15 cm的土壤含水率、水势进行监测,结果表明:(1)表层5 cm土壤水分日变化呈复杂波形,受不同覆垄处理和季节性天气变化的影响显著;(2)0~20 cm土层的水分年变化主要受降雨、露水和蒸发强度的影响,表现为春冬干、夏秋湿的特点,在11月至翌年2月期间MB和DB覆垄处理土壤水分净损失量要高于CK裸地垄,而在作物生育期内(5-9月)覆垄处理土壤储水净增量为DB最大(36.35 mm)、MB次之(30.73 mm)、CK最小(16.30 mm);(3)MB和DB覆垄能明显加快雨露叠加,增加土壤水储存,而CK处理下叠加效应弱,且深层土壤对降雨不敏感,具有滞后性,但随着连续降雨的发生,表层土壤储水量加大,这种滞后性明显减弱;(4)0~20 cm土层土壤储水量日变化幅度为夏季最大(平均1.20 mm·d^-1),春季次之(1.03 mm·d^-1),秋季最小(0.79 mm·d^-1),全年水分净收获总量为DB最大(24.9 mm)、MB略低(21.5 mm)、CK最小(11.4 mm)。整体而言,只用地布覆垄具有最好的集水效果,这种防草地布可多年使用,无地膜碎片化污染问题,但在无降雨时期,垄沟内因土壤水分高,其蒸发强度略高于裸地处理。

园艺地布微垄覆盖对渭北旱地矮化苹果根域土壤水分的影响

通过田间定位观测,设置(园艺地布微垄覆盖、秸秆覆盖和清耕)3个处理,分析不同降水年型下园艺地布微垄覆盖渭北旱地矮化苹果根域土壤贮水、果园耗水、果树产量及水分利用效率的变化。结果表明:降水欠水年、平水年园艺地布微垄覆盖果树生育期果园0～300 cm土层平均贮水量分别比清耕处理提高6.88%、8.02%,比秸秆覆盖处理提高1.64%、2.92%,显著提高了果树根系主要分布层土壤贮水量与供水能力,增强了对果园深层土壤贮水的调蓄作用,对深层土壤贮水的调蓄作用优于秸秆覆盖,其对果园土壤贮水平衡状况的影响与果树生长发育中后期降水量密切相关。园艺地布微垄覆盖增加了果园耗水量,改变了果园耗水结构,在欠水年、平水年与清耕相比显著减少了无效蒸发,减少量为26.94 mm、26.50 mm,同时与清耕相比显著提高了果树蒸腾耗水量,提高16.57%、12.09%,蒸发量和蒸腾量与秸秆相比皆无显著差异。园艺地布微垄覆盖具有显著的增产作用,欠水年、平水年水分利用效率分别比清耕提高9.32%、5.49%,但果树产量和水分利用效率与秸秆相比皆无显著差异。园艺地布微垄覆盖可作为渭北旱地矮化苹果栽培体系中的一种有效的蓄水保墒技术措施。

针织布面异纤的分析与控制

探讨布面异纤的分析方法及控制措施。结合生产实际,阐述布面异纤的概念及要求,并对布面异纤的来源、种类、特点及危害进行分析。指出:异纤会对布面外观质量产生很大影响,从而影响企业效益。认为:减少或预防棉纱异纤是一个系统工程,从棉花种植、收购、加工到纺织生产的各环节都必须给予重视。纺纱企业必须根据不同产品的质量要求优化配棉方案,增加异纤清除设备,加强生产管理,以减少异纤影响,提高布面质量的整体水平。