Finishing Effect on Warmth Property of Cotton/Kapok Blended Knitted Fabric

Nowadays,more and more natural or functional fibers are being investigated due to their utilization in thermal underwear.Kapok fiber is one of the natural cellulosic fibers whose source is the kapok plant. It has hollow body and sealed tail,which exhibits desirable features required for functional textiles of this nature. In this study,cotton / kapok( 80 /20 by mass) blended yarn with two types of yarn size 18. 5 and 14. 8 tex,respectively are knitted into plain stitches. The fabrics are undergone with an optimal preparation plan according to orthogonal design. Then,after dyeing and softening,fabric properties including thermal and water-vapour resistances, wicking property, pilling behaviour, and surface morphology,are tested and scrutinized for their candidacy for thermal underwear. The results showed that cotton / kapok blended fabrics have good thermal resistance which is significantly higher than those of cotton / modal blended fabrics,and the same water vapour resistance compared with cotton / modal blended fabrics which are normally used as underwear. Cotton / modal blended knitted fabrics has better pilling grade than cotton / kapok blended fabrics. Meanwhile, the cotton / kapok blends fabrics have good wicking property. Collectively,it was concluded that cotton / kapok blended fabric was appropriate for thermal underwear. However,the main limitation of these fabrics is their pilling properties.

Modeling and Numerical Simulation of Heat Transfers in a Metallic Pressure Cooker Isolated with Kapok Wool

In this work, a numerical study of heat transfers in a metallic pressure cooker isolated with kapok wool was carried out. This equipment works like a thermos, allowing finishing cooking meals only thanks to the heat stored at the beginning of cooking, which generates energy savings. Cooked meals are also kept hot for long hours. In our previous work, we have highlighted the performances of the pressure cooker when making common dishes in Burkina Faso. Also, the parameters (thickness and density) of the insulating matrix allowing having such performances as well as the influence of the climatic conditions on the pressure cooker operation were analyzed in detail in this present work. The numerical methodology is based on the nodal method and the transfer equations obtained by making an energy balance on each node have been discretized using an implicit scheme with finite differences and resolved by the Gauss algorithm. Numerical results validated experimentally show that the thickness of the kapok wool as well as its density play an important role in the pressure cooker operation. In addition, equipment performances are very little influenced by the weather conditions of the city of Ouagadougou (Burkina Faso).

Sono-Transesterification of Kapok Seed Oil with CaO:BaO-(x:y)/Active Natural Zeolite Catalyst

Kapok seed oil is an environmentally friendly biodiesel feedstock.The problem of the best catalyst for transester-ification of Kapok seed oil still continues today.The research developed a base-heterogeneous catalyst with the effect of ultrasonic waves during transesterification.So,the study aims:(1)to determine the type of natural zeolite used,(2)to determine the characteristics of the synthesized CaO:BaO/ANZ catalyst,and(3)to determine the effectiveness of the CaO:BaO/ANZ catalyst in the biodiesel production process through sono-transeste rification of kapok seed oil.The research stages consisted of:(1)activation of natural zeolite and its characterization,(2)preparation of CaO:BaO/ANZ catalyst,(3)characterization of CaO:BaO/ANZ catalyst,(4)esterification and uti-lization of catalyst in the transesterification,(5)analysis of transesterified products.The results showed that the natural zeolite type from the southerm area of Malang is mordenite(MOR)type.Then,after the natural zeolite was impregnated,the obtained catalyst compositions were CaO:BaO-9:9/ANZ,CaO:BaO-14:9/ANZ,and CaO:BaO-4:11/ANZ with a surface area of 129.7;124.6;128.5 m^(2)/g,and acidity of 1.037;0.254;and 0.685 mmol/g,respectively.The best catalyst for transesterification of kapok seed oil was CaO:BaO-9:9/ANZ,which resulted in a biodiesel yield of 73.6%with a density of 889.6 kg/m^(3) and kinematic viscosity of 2.987 cSt.The characteristics of the produced biodiesel meet requirement of SNI 7182:2015.

Experimental Study of a Metallic Pressure Cooker Insulated with Kapok Wool

This work is devoted to an experimental study of metallic pressure cooker insulated with kapok wool, a vegetal biodegradable fiber. Experiments conducted on the cooling of hot water in the equipment revealed very low heat losses and a time constant of 60 hours on average. As a result, the equipment makes it possible to finish cooking meals only thanks to the heat stored at the beginning of cooking and keeps cooked dishes warm for long hours. The thermal phase shift of the pressure cooker is around 7?h. Cooking tests conducted on some local dishes revealed about 70% butane gas savings for cooking cowpea and white rice, 38% for cooking fatty rice, 75% for pasta and couscous, and 30% for cooking potato stew. These results show that this technology can contribute to minimizing?energy consumption in the restaurant sector.

镍/木棉纤维衍生碳复合材料的制备及吸波性能研究

近年来,生物质碳因成本低廉、易制备、理化性能优异和具有多孔结构被广泛应用于吸波领域。然而,其吸波性能仍然受较高电导率引发的不良阻抗限制。在此,使用镍(Ni)改性木棉纤维,并使用不同的碳化温度获得镍/木棉纤维衍生碳(Ni/C)复合材料。扫描电镜结果表明,随着碳化温度的升高,Ni颗粒的尺寸增加,且木棉纤维表面出现更多的缺陷结构。XRD和XPS结果证明了Ni和木棉纤维衍生碳的成功复合。Raman结果表明碳化温度的升高导致碳组分石墨化程度增加,提高了复合材料的传导损耗能力。最后,我们将复合材料与石蜡以5∶95的超低填充比例混合,Ni/C-800展现出-52.6 dB的反射损耗值和8.32 GHz的有效吸收带宽。复合材料优异的吸波性能取决于衰减能力和阻抗匹配的协同、介电损耗和磁损耗的共同作用以及大比表面积和中空多孔结构造成的多重散射能力的增强。

INVESTIGATION ON SOUND ABSORPTION PROPERTIES OF KAPOK FIBERS

Sound absorption properties of natural kapok fibers have been investigated. Kapok fibrous assemblies with different bulk density, thickness, fiber length and orientation were manufactured, and their acoustical performances were evaluated by using an impedance tube instrument. Results show that the kapok fiber has excellent acoustical damping performance due to its natural hollow structure, and the sound absorption coefficients of kapok fibrous assemblies are significantly affected by the bulk density, thickness and arrangement of kapok fibers but less dependent on the fiber length. Compared with assemblies of commercial glass wool and degreasing cotton fibers, the kapok fiber assemblies with the same thickness but much smaller bulk density may have the similar sound absorption coefficients. Theoretical modelling of the acoustical damping performance of kapok fibers shows a good agreement with the experimental data. All the results demonstrate that kapok fiber is a promising light and environment-friendly sound absorption material.

Self-nitrogen-doped porous biochar derived from kapok (Ceiba insignis) fibers： Effect of pyrolysis temperature and high electrochemical performance

Self-nitrogen-doped porous biochar derived from kapok fibers possesses unique structure and excel- lent electrochemical performance. In this study, one-step pyrolysis method was introduced to prepare porous biochar from kapok fibers, and effect of pyrolysis temperature on structure and electrochemical performance of the porous biochar was investigated. It was found that pyrolysis temperature played an important role in determining microstructure of the biochar. At the pyrolysis temperature of 750 ℃, the as-prepared biochar （CKF-750） represented a largest specific surface area of 1125.7 m^2 g^-1 and pore vol- ume of 0.7130 m^3 g^-1, and hence brings CKF-750 a highest specific capacitance of 283 F g^-1 at a current density of I A g^-1 in a 6 mol L^-1 KOH electrolyte. Furthermore, the cycle stability of CKF-750 was wonderful, and the specific capacitance retained almost constant after 10000 cycles. Therefore, the pyrolysis tem- perature of 750 ℃ is optimal for the preparation of porous hiochar as an outstanding electrode material for supercapacitor.

纺纱方式和木棉纤维含量对Lyocell/木棉纤维/羊毛混纺纱性能的影响

为了提高含木棉混纺纱线的性能,扩大木棉纤维的应用范围,研究了纺纱方式和木棉纤维含量对Lyocell/木棉纤维/羊毛混纺纱性能的影响。采用集聚纺和涡流纺分别纺制了80/10/10、70/20/10、60/30/10/比例的6组Lyocell/木棉纤维/羊毛混纺纱;观察纱线的外观形态,对其捻度、毛羽、条干、强度、回潮率和含水率进行了测试和分析;并对纱线的质量进行了对比评价。结果表明:混纺比对Lyocell/木棉纤维/羊毛/混纺纱捻度的影响较小;提高木棉纤维的比例,混纺纱的回潮率和含水率上升,吸湿性能提高,断裂强力、断裂伸长率和条干均匀度均降低,毛羽增多;Lyocell/木棉纤维/羊毛比例为80/10/10混纺纱综合质量最优,可用于中高档内衣、卫衣面料的开发。

FACILE FABRICATION OF LARGE SCALE MICROTUBES WITH A NATURAL TEMPLATE—KAPOK FIBER

A newly natural fine template, kapok fiber, for microtube preparation was reported. Large scale microtubes with high length/diameter ratio and controllable wall thickness and morphology have been successfully fabricated with this template. It is a wildly available, low-cost, environmental friendly and fine structured natural template for microtubes. Its thin wall thickness is only about 1-2 um that means the whole template material is tiny and easy for removing. Even there is any residue the amount can be ignored. When the template is covered with a shell component, hollow structured microtube could be obtained by removing the thin inner template, and its shape could be the same as that of the original template （positive copy of the template＇s shape）. The products have high length/diameter ratio and uniform tubular structure. By further modifying the fabricating methods, facile fabrication not only exists for polypyrrole （PPy） in electrochemical deposition, but also for many other organic and inorganic materials. The surface morphology and wall thickness of the resultant microtubes can be easily modulated by controlling the processing conditions. This natural fiber is predicted to be a fine template for fabricating large scale microtubes with large cavity and high length/diameter ratio.

Research and application of kapok fiber as an absorbing material: A mini review

Kapok fiber corresponds to the seed hairs of the kapok tree（Ceiba pentandra）, and is a typical cellulosic fiber with the features of thin cell wall, large lumen, low density and hydrophobic–oleophilic properties. As a type of renewable natural plant fiber, kapok fiber is abundant,biocompatible and biodegradable, and its full exploration and potential application have received increasing attention in both academic and industrial fields. Based on the structure and properties of kapok fiber, this review provides a summary of recent research on kapok fiber including chemical and physical treatments, kapok fiber-based composite materials, and the application of kapok fiber as an absorbent material for oils, metal ions, dyes, and sound,with special attention to its use as an oil-absorbing material, one predominant application of kapok fiber in the coming future.

Investigation of acetylated kapok fibers on the sorption of oil in water

Kapok fibers have been acetylated for oil spill cleanup in the aqueous environment. The structures of raw and acetylated kapok fiber were characterized using Fourier transform infrared （FT-IR） spectroscopy and scanning electron microscopy （SEM）. Without severe damage to the lumen structures, the kapok fibers were successfully acetylated and the resulting fibers exhibited a better oil sorption capacity than raw fibers for diesel and soybean oil. Compared with high viscosity soybean oil, low viscosity diesel shows a better affinity to the surface of acetylated fibers. Sorption kinetics is fitted well by the pseudo second-order model, and the equilibrium data can be described by the Freundlich isotherm model. The results implied that acetylated kapok fiber can be used as the substitute for non-biodegradable oil sorption materials.

桑叶等复合粉剂对灵山麻鸡生长性能、消化酶活性、肠道菌群及血清免疫指标的影响

试验旨在探讨桑叶等复合粉剂对灵山麻鸡生长性能、消化酶活性、肠道菌群及血清免疫指标的影响。选取200只56日龄体重相近、健康的灵山麻鸡,随机分为4组,每组5个重复,每个重复10只鸡。对照组饲喂基础饲粮,试验1组、试验2组和试验3组分别在基础饲粮中添加2.0%、1.0%和0.5%桑叶等复合粉剂。试验期42 d。结果显示,与对照组相比,试验2组麻鸡平均日增重升高了12.65%(P<0.05),料重比显著降低(P<0.05);各试验组大肠杆菌、沙门氏菌的数量及腹泻率均显著降低(P<0.05),十二指肠胰蛋白酶、淀粉酶、脂肪酶及盲肠纤维素酶活性显著提高(P<0.05),血清免疫球蛋白G(IgG)含量分别提高了40.69%、49.88%和25.72%(P<0.05),血清总蛋白(TP)、白蛋白(ALB)和球蛋白(GLB)含量显著升高(P<0.05),白球比(A/G)显著降低(P<0.05)。研究表明,桑叶等复合粉剂能够提高灵山麻鸡生长性能、消化酶活性,降低腹泻率,改善灵山麻鸡的血清生化指标和免疫功能,桑叶等复合粉剂适宜添加量为1.0%。

广东省木棉古树分布与健康及影响因子分析

以广东省古树名木普查数据为基础,采用皮尔逊相关系数和线性混合模型分析了全省木棉Bombax ceiba古树的资源特征及影响因子。结果表明广东省现存木棉古树1280株,树龄、树高、胸围和冠幅主要集中在100~200 a,12.0~22.0 m,200~400 cm和8.0~20.0 m。木棉古树空间分布差异大,以珠三角地区为主,粤东西地区较少,粤北地区零星分布。木棉古树树龄与环境因子无显著相关性;树高与多数环境因子存在显著相关性;胸围与季节温度差、年均温度差呈显著正相关,冠幅与年均温度呈极显著负相关,但胸径和冠幅与坡度、坡向和年均降雨量均无显著相关性。结论,广东省木棉古树主要分布在广州市、东莞市、惠州市等珠三角城市,健康状况整体较好,树洞(中空)、病虫害、枯断枝比例、环境污染物和生长空间是影响木棉古树健康的主要因子。

Porous hollow carbon tube derived from kapok fibres as efficient metal-free oxygen reduction catalysts

Pyrogenic biomass carbon has been deemed a promising alternative to Pt/C for the oxygen reduction reaction(ORR) owing to its low cost, excellent activity, and eco-friendly properties. Herein, a porous carbon tube material derived from kapok fibres was prepared by combining activation with pyrolysis. Electrochemical measurements demonstrated that the kapok fibre-derived material prepared at 900°C had excellent ORR performance with a half-wave potential –0.14 V(vs. Ag/Ag Cl) close to that of commercial Pt/C(–0.13 V vs. Ag/Ag Cl) in 0.1 mol L–1 KOH. The prepared material also displayed remarkable methanol tolerance and durability. Furthermore, the maximum power density output of the microbial fuel cell using the prepared material was(801±40) mW m–2, comparable to that of the Pt/C cathode((778±31) mW m–2). The present work provides a facile way of using economical and renewable biomass to develop a porous structure and high-activity cathode ORR catalyst for fuel cell applications.

木棉花超微粉对灵山麻鸡生长性能及防腹泻效果的影响

[目的]为中药在养禽业上“减抗”“替抗”的推广应用提供参考。[方法]选取56日龄341 g左右的灵山麻鸡200羽,随机分为4组,每组10羽鸡、每组5个重复,对照组饲喂基础日粮,试验组在基础日粮上分别添加0.5%、1.0%、2.0%木棉花超微粉,饲养试验为42 d,测定试验鸡的生长性能、腹泻率、肠道菌群、血清免疫球蛋白等指标。[结果]与对照组相比,木棉花超微粉对试验鸡的平均日采食量、血清免疫球蛋白IgA、IgM均无显著影响,但均能不同程度地提高平均日增质量,中剂量试验组增加最多(12.67%);试验组灵山麻鸡血清中IgG含量分别显著提高36.13%、55.35%、26.18%,且中剂量试验组效果最好。[结论]在饲料中添加木棉花超微粉可促进灵山麻鸡生长,同时降低肠道菌群的丰度和腹泻率,显著提高血清免疫球蛋白IgG的含量,且以1%木棉花超微粉效果最佳。

具有木棉纤维的ABA结构隔声性能试验与计算分析

前围隔音垫主要用于隔绝发动机的噪声,防止噪声传到乘客舱,其结构一般为ABA(吸声层-隔声层-吸声层)。ABA结构中吸声层(A)为多孔棉毡,由纤维材料制作而成。该文章使用木棉纤维、超细纤维制作多孔棉毡,测试并对比两种棉毡的吸声系数。基于两种纤维制作ABA结构样件,并进行了隔振性能的测试。建立了ABA结构的隔声特性的计算模型,并验证模型的有效性。利用建立的模型,计算分析不同吸声层材料构成、不同厚度参数的ABA结构的隔声性能。

具有高效电磁屏蔽性能的银纳米线/木棉纤维素纸的制备与研究

以多元醇法制备出的银纳米线作为导电填料,木棉纤维素微纤维作为载体,通过真空抽滤制成导电复合纸,使用扫描电子显微镜、X射线衍射仪、X射线光电子能谱仪、四探针测试仪、矢量网络分析仪对复合纸进行表征,探究了银纳米线含量对其电导率与电磁屏蔽效能的影响。结果显示,银纳米线作为一种一维的银单质纳米材料能够均匀地分布在复合纸中,并且形成优异的导电网络。当纯纤维素纸中加入2.5%(质量分数)的银纳米线,纸的电阻由470.57 MΩ•cm骤降至1.26 mΩ•cm。当银纳米线的浓度从2.5%提升至10%后,纸的电导率从793.65 S/cm提升至3039.51 S/cm,电磁屏蔽效能也从38.1 dB提升至61.5 dB。

硼氮共掺杂生物质炭的制备及吸附性能研究

以木棉、硼酸(HBO_(3))、尿素(CO(NH_(2))_(2))为原料,在氨气(NH_(3))气氛下通过高温反应制备了硼氮共掺杂生物质炭材料,利用聚乙烯亚胺(PEI)对硼碳氮(BCN)材料进行处理,得到PEI-BCN材料,并研究了该材料的吸附性能。结果表明:当反应温度为1 100℃时,制备得到的BCN材料为多孔结构,其平均孔径为11.0 nm;BCN材料的吸附能力优于生物质炭,经PEI改性处理后,BCN材料的吸附性能得到大幅提高,其对有机染料孔雀石绿(MG)的吸附量高达710.0 mg/g;PEI-BCN材料的吸附与准一级吸附动力学模型吻合,其对MG的吸附属于Langmuir等温吸附。

紬丝/木棉非织造材料制备与性能评价

以紬丝和木棉纤维为原料,经开松、碱处理、打浆、湿法成网和热压等工艺制备不同混合比例下紬丝/木棉非织造材料(KSN),分别测试评价了其形态结构、弯曲性能、拉伸性能和透气性。结果表明:KSN中紬丝近似圆柱形,表面出现明显分丝帚化,木棉纤维呈扁平带状,纤维表面仅出现少量纤丝。随着木棉纤维比例的增加,KSN结构变得紧密,样品厚度、透气率减小,弯曲刚度、断裂强度显著提高。