聚酯纤维针刺非织造材料的吸声性能研究

主要研究了聚酯纤维针刺非织造材料在200~2 000 Hz声波频率范围内的吸声性能。从材料的厚度、针刺密度、表面粗糙度和组成纤维四方面来研究其吸声性能的影响因素。由实验得出,非织造材料的吸声性能主要取决于材料的厚度和表面特征,组成纤维也有一定的影响作用。     

Sound-Absorption Properties of Kapok Fiber Nonwoven Fabrics at Low Frequency

In this study, the sound-absorption properties of kapok fiber nonwoven fabrics were investigated in the frequency region of 100–2500 Hz using the impedance tube method. The effects of physical parameters including fiber mixing ratio, bulk density, and thickness on sound-absorption properties of composites were studied. The comparisons of kapok fiber with polypropylene fiber and hollow polyester fiber indicated that as a natural fiber, kapok fiber had superior acoustical properties at low frequency. A new simple model had been developed to predict the sound absorption coefficient of kapok fiber nonwoven composites at low frequency.     

木棉及其混合纤维非织造材料吸声预测模型

以Allard模型为基础,采用等效流体的方法,拟建立一个能够准确描述木棉及其混合纤维非织造材料吸声行为的吸声模型。该模型结合木棉纤维的大中空结构,考虑了材料的热传导效应及纤维框架的柔软性。使用新建立的吸声模型及Allard模型分别对4种不同结构的木棉纤维非织造材料的吸声系数及比表面阻抗进行了计算,并将计算值与实验样品的测量值进行比较。结果表明:新模型的计算结果更接近实验值,说明新模型更适用于木棉及其混合纤维非织造材料吸声性能的预测,为工业产品的设计提供了理论参考。     

木棉纤维的吸湿排汗性能测试

服装面料的吸湿导湿性与服装穿着舒适性密切相关。为了获得较好的穿着舒适性,针对木棉纤维天然环保以及在光泽、手感、吸湿性、保暖性方面具有独特优势,分别测试和分析了木棉纤维、棉纤维、Coolplus纤维对水和汗液的吸湿导湿性能。通过比较分析发现:在这些纤维中,木棉的吸湿性良好,导湿性最好,其对水的吸湿率为115%,导湿率为99.13%;对汗液的吸湿率为189%,导湿率为93.65%。     

汽车内饰材料的吸声性能

分析了针刺非织造汽车内饰黄麻毡的面密度与吸声性能的关系,并在黄麻纤维中混入一定量的铝纤维,分析铝纤维的混入质量、混合方式对其吸声性能的影响.结果表明:在同一测试声波频率下,黄麻毯的吸声性能随着面密度的增加而提高,在面密度为764 g/m2时吸声性能最好;铝纤维的加入有利于吸声性能的提高,吸声性能随着铝纤维含量的增加而提...     

简述装饰织物吸声隔音性能的应用与研究

装饰织物的功能性日益为人们所关注 ,有关其吸声隔音性能的实际应用和理论研究亦均有报道。本文针对装饰织物吸声隔音的基本原理和应用作一简述。     

Sound absorption properties of composite structure with activated carbon fiber felts

This paper is intended to study the influence of different factors on the sound absorption properties of composite structure with activated carbon fiber felts. Activated carbon fiber felts made from viscose fiber mats were prepared and later combined with perforated panels to form four different composite sound absorption structures. Based on the transfer function method, the impedance tube was used to test the sound absorption coefficients of composite structure in an acoustic range of 80–6300?Hz frequencies. Analysis was made to discuss the influence of such factors on the sound absorption properties as the position of activated carbon fiber felts, thickness, and air space. The results demonstrated that the composite structure displayed different sound absorption properties at different frequencies. Perforated panels played the dominant role in sound absorption by the occurrence of resonance at 80–3500?Hz frequencies, while porous materials contributed the most at 3500–6300?Hz frequencies. At 80–3500?Hz frequencies, the best performance could be observed in the third type of composite structure with changes in the position of activated carbon fiber; the first resonance frequency of the first type of composite structure and perforated panel structure was basically the same, and that of the remaining three types significantly shifted towards the low frequencies with the same scale. In smaller thickness range, with the increase in the thickness of activated carbon fiber felts, sound absorption coefficients of the first and second types of composite structure increased, the first resonance frequency of the first type showing no apparent shift towards the low frequencies compared with what was shown in the second type; but when the thickness arrived at 15.6?mm, sound absorption properties of the composite structure had similar traits to that performed by porous materials in an acoustic range of 80–6300?Hz frequencies. With the increase in the distance of air space, sound absorption properties were improving at 80–650?Hz frequencies but decreasing at 650–3500?Hz frequencies, the first resonance frequency moving towards the low frequencies. At 3500–6300?Hz frequencies, as the position of activated carbon fiber felts and the distance of air space varied, sound absorption coefficients were basically unchanged; while as thickness increased, sound absorption coefficients improved.     

天然纤维一木棉纤维的研究探讨

文章论述了木棉作为一种可降解的天然纤维,具有内在疏水性和多孔性,是理想的制造清理油污用的吸收剂的材料,并详细阐述了木棉纤维在纺织领域的其他应用。     

减震隔声降噪地垫的研发

介绍我国分户楼板隔声及其隔声研究现状,详细阐述多层复合结构的减震隔声降噪地垫的结构、性能和安装,减震隔声降噪地垫与木地板配合使用,将其铺装于扫平层的140 mm厚现浇钢筋混凝土楼板之上,经江苏省建工建材检测中心检测,撞击声隔声为61 dB,能很好地满足住宅分户楼板撞击声隔声L'nT,W≤65 dB的要求。     

碱处理对木棉纤维形态结构及靛蓝染色性能的影响

通过常温和高温碱处理对木棉纤维进行表面处理,测试了纤维的失重率及吸湿率。研究了常温碱处理和高温碱处理对木棉纤维表面形态、化学结构、结晶度及靛蓝上染率的影响。结果表明,碱处理后的木棉纤维重量下降、吸湿率降低;当碱液浓度为1~15g/L,90℃碱处理后的木棉纤维的上染率较30℃碱处理后的纤维的上染率低;高温处理后的木棉纤维表面出现明显的沟痕;碱处理后木棉纤维中的羰基特征峰强度降低,结晶度随碱液浓度增加整体降低。     

木棉纤维的结构与热性能

文章采用化学分析、SEM、红外光谱、X-衍射和热分析研究了木棉纤维的化学组成、结晶结构和热学性能,并与普通棉纤维进行了比较。结果表明木棉纤维具有高含量的木质素和半纤维素,其胞壁很薄,中空度达90％。木棉纤维的结晶度和晶粒尺寸小于棉纤维,不过其晶粒取向度较高。红外光谱也显示木棉纤维的木聚糖结构比较特殊,具有异常高的乙酰基的取代度。木棉纤维的热分解温度明显低于棉纤维,不过其热分解的温度区间较宽。     

An Investigation of the Sound Absorption Properties of Flax/Epoxy Composites Compared with Glass/Epoxy Composites

Natural fiber based composites are becoming attractive candidates for use in various applications owing to their mechanical and sound absorption properties. It has been proposed that they could potentially replace glass fiber composites owing to their minimized impact on human health and the environment. Though studies have been dedicated to understanding their mechanical properties, few focus on quantifying their sound attenuation behavior. We investigated the sound absorption properties of flax/epoxy composites and found them to be superior to those of glass/epoxy composites. A noteworthy result was that the noise reduction coefficient increased from an average value of 0.095–0.11 for unidirectional flax/epoxy composite and to 0.10 for cross-ply flax/epoxy system. Results suggest that flax/epoxy composites could be less expensive, viable and ecologically superior substitutes for glass-fiber based composites, particularly in applications where sound absorption is important.     

膳食纤维对营养素吸收的影响

膳食纤维是人体所必需的营养素之一,其本身不能直接被机体所吸收利用,但对胃肠道功能及多种营养素的吸收都有一定的影响。这些营养素包括常量营养素-蛋白质、脂类及碳水化合物和微量营养素--维生素、矿物质及微量元素。膳食纤维对于蛋白质代谢及氮平衡的影响不大,但可减少脂类和碳水化合物的吸收及利用。有些实验显示膳食纤维对矿物质及微量元素的吸收无影响,而另一些实验则表明纤维可促进矿物质及微量元素的吸收利用。有些实验结果表明膳食纤维可损害维生素A、维生素E及维生素B12的吸收,但对其它维生素的生物利用无明显影响。     

木棉纤维非织造材料性能研究

利用非织造技术将天然木棉纤维与涤纶加工成结构和性能稳定的非织造材料,并进行性能测试.结果表明:非织造技术可以用于加工木棉纤维,能较好地保持木棉纤维的中空度;合适的工艺条件可以制得性能良好的非织造制品;制品的厚度、透气量、保暖性和压缩弹性率等性能都与其面密度有关.     

竹原纤维/聚氨酯复合材料的隔音性能

为充分发挥天然竹原纤维的可再生性和生物分解性,减少隔音复合材料对环境的负荷,并进一步改善竹原纤维/聚氨酯复合材料的隔音性能,以天然环保和可再生的竹原纤维为增强材料,以聚氨酯为基体,制备了一系列不同方式复合的隔音复合材料。研究了竹原纤维的排列方式与质量分数、及氢氧化钠溶液表面处理对复合材料隔音性能的影响。结果表明：竹原纤维采用直铺法制成的复合材料隔音性能最好;竹原纤维经氢氧化钠溶液处理后制成的复合材料其隔音性能显著提高;随着竹原纤维质量分数增加,复合材料的隔音性能增大。     

洗水对含木棉纤维牛仔面料性能的影响

采用普洗、氧漂、氯漂、锰漂和酵素漂等方法对含木棉牛仔面料进行处理,探讨不同洗水方法对含木棉牛仔面料的K/S值、透气性、断裂强力和断裂伸长率的影响。结果表明,除锰漂、氧漂外,其它三种洗水方法的褪色效果不明显;经过氧漂、锰漂洗水后的牛仔面料,透气率增加14%以上,酵素漂的透气率下降超过14%,而氯漂和普洗的透气率基本不变;氧漂、氯漂处理面料的经纬向断裂强力增加,而锰漂、酵素漂的减小,普洗经向减小,纬向变化不大。     

涤纶非织造吸声材料的吸声性能研究

研究涤纶非织造吸声材料的吸声性能。利用具有细度梯度的涤纶纤维制备了12种非织造吸声材料,测试分析了不同加固方式、纤维细度、针刺密度和材料厚度对涤纶纤维非织造吸声材料吸声性能的影响。结果表明:在所制备的涤纶非织造吸声材料中,采用针刺加固工艺、较细的纤维细度、较小的针刺密度以及较大的材料厚度,可以获得更好的吸声效果。认为:涤纶纤维可以作为非织造吸声材料应用,其吸声性能较好。     

大孔树脂吸附大豆异黄酮特性的研究

比较 9种不同型号大孔吸附树脂对大豆异黄酮的吸附性质 ,从中筛选出效果较好的LSA 8型树脂进行吸附动力学及热力学特性的研究 ,得到该树脂在不同温度下对大豆异黄酮的吸附等温线和以大豆异黄酮原液浓度及时间为参数的吸附动力学曲线方程。     

亚麻织物丝光后纤维吸附性的变化

研究分析亚麻织物丝光后纤维吸附性的变化，以指导企业生产，达到合理使用染化料及避免浪费的目的。