溶胶－凝胶法制备SiO2/NR复合材料的力学性能

将SiO2与天然橡胶的制备工艺相结合，先以价格低廉的水玻璃为原料，采用溶胶－凝胶法制备SiO2溶胶和凝胶，再以天然鲜胶乳共沉－共凝制备SiO2/NR复合材料，考察了制备工艺条件对复合材料力学性能的影响。结果表明，制备SiO2/NR复合材料较适宜的复合工艺为院水玻璃与乙酸乙酯反应温度30益，乙酸乙酯和水玻璃溶液中所含SiO2的摩尔比n为0.8∶1，水玻璃浓度为6.5%。当SiO2用量为10份时，复合材料的拉伸强度和撕裂强度分别达到了33.4MPa和47.1kN·m-1。     

静电纺丝制备魔芋葡甘聚糖-纳米四氧化三铁纳米纤维膜结构及性能

将魔芋葡甘聚糖-纳米四氧化三铁共混,通过静电纺丝技术进一步制备纳米纤维膜,研究纳米四氧化三铁、KGM、甘油、Na₂CO₃含量对纳米纤维膜力学性能的影响。结果表明,纳米Fe₃O₄、KGM、甘油、Na₂CO₃含量对纳米纤维膜性能有较大影响,当纳米Fe₃O₄含量为1.0%,KGM含量为1.2%,甘油含量为0.1%,Na₂CO₃含量为0.1%时,制得的纳米纤维膜的拉伸强度为28.35 MPa,断裂伸长率为6.42%。X射线衍射（XRD）和扫描电镜（SEM）证明静电使KGM分子和Fe₃O₄粒子间存在着较强的相互作用,形成纤维表面的微孔结构薄膜。此外其静电纺丝增加了薄膜的性能,静电纺丝使膜的拉伸强度和断裂伸长率分别提高了72.4%和32.0%,水蒸汽透过系数和氧气透过率分别降低了35.2%和49.7%,且通过静电纺丝可使膜具有一定抗氧化性能。     

环氧化天然橡胶包覆CaCO3填充LDPE的技术

选用环氧化程度摩尔分数为25%的环氧化天然橡胶胶乳(ENRL-25)包覆轻质CaCO3,研究了处理方法、ENRL-25用量和CaCO3填充量对CaCO3 /LDPE(低密度聚乙烯)复合材料结构与性能的影响,并与钛酸酯偶联剂NDZ-201处理CaCO3进行了对比。结果表明:ENRL-25和NDZ-201湿法包覆CaCO3效果较好,使CaCO3 /LDPE材料在拉伸强度保持较高的情况下,拉伸弹性模量、撕裂强度和扯断伸长率得到有效的提高;在采用最佳改性剂用量时,ENRL-25改性CaCO3/LDPE复合材料的撕裂强度和扯断伸长率较优,而NDZ-201改性CaCO3/LDPE复合材料的拉伸强度和拉伸弹性模量较优。SEM的分析结果表明,包覆CaCO3与LDPE的界面作用强度提高,材料的破坏不是始于CaCO3粒子脱粘,而是始于基质的变形破坏。      

超细SiO2/NR复合材料的制备工艺及其力学性能

利用乳液共沉原理、正交实验法,研究了Na2SiO3·9H2O与盐酸在助剂的作用下生成的SiO2乳液与天然胶乳共凝制备超细SiO2/NR复合材料的工艺。结果表明:由Na2SiO3·9H2O的质量浓度、反应时间、反应温度3个因子适宜水平组合,采用乳液共沉法制备的超细SiO2/NR复合材料的300％定伸应力为6.43 MPa,拉伸强度为29.04 MPa,撕裂强度为56.88 kN/m,与纯胶、普通SiO2/NR复合材料相比,超细SiO2/NR复合材料的力学性能得到一定程度改善。在本实验条件下,超细SiO2/NR复合材料的最佳制备工艺条件(适宜的因子水平组合)是Na2SiO3·9H2O的质量浓度第1份为280 g/L、第2份为100 g/L,反应时间为30 min、反应温度为80℃。      

同铃壳内籽棉拉伸特性试验与分析

针对采棉机籽棉采收或预处理过程中,机械力过大对棉花纤维拉伸导致单粒籽棉率较高的问题,利用万能试验机对籽棉拉伸特性进行试验研究及分析。试验表明：在拉伸过程中单粒籽棉上的纤维断裂出现情况较少,多为籽棉间相互缠绕的纤维随拉伸发生分离,且籽棉间纤维分离力小于籽棉纤维断裂力;拉伸曲线表明,随着棉纤维拉伸长度的增大,拉力先是快速增大,当拉力达到最大值附近时,表现为基本稳定状态,随后快速减少,直至拉力消失;籽棉间纤维平均分离力随加载速率的增加而线性增加（R²＝0.978 8）。研究结果可为棉花收获装备采收及预处理部件、工作参数优化和相关仿真分析提供参考。     

甘蔗渣活性炭制备研究进展

随着环境保护要求的提高,近年来我国活性炭工业发展迅猛,甘蔗渣作为制糖加工过程中的副产物,碳素含量高、产量大、价格低廉,是制备生物质活性炭的优良材料.主要综述了甘蔗渣作为原料制备活性炭的工艺方法,包括汽体活化法、化学试剂活化法、微波辅助加法、物理-化学活化法等,为产业化生产甘蔗渣活性炭及其应用提供参考.     

利用能源植物斑茅纤维固态发酵产纤维素酶及其糖化的研究

以能源植物斑茅(Erianthus arundinaceus)为材料,对其纤维成分、产酶条件和糖化条件进行了分析。结果表明:斑茅含有纤维素43.77%、半纤维素28.57%、木质素11.01%;对斑茅进行预处理后,纤维中纤维素的含量提高至72.54%,半纤维素含量降低至13.02%,木质素的含量降低至3.34%。利用预处理的斑茅纤维进行固态发酵产酶,其最佳的产酶条件为:茅麸比1∶3,固液比1∶2,氮源(脲)0.75%,初始pH 5.0,32℃发酵培养72 h;相对于利用未经预处理的斑茅纤维为原料,其FPA酶活提高210.9%,达到20.74 U/g,CMC酶活提高239.1%,达到218.26 U/g。以纤维素酶对斑茅纤维进行糖化,糖化率达到40.60%。     

颗粒状天然橡胶制备新方法及其性能的研究

对比天然橡胶5号胶，采用海藻酸钠作为辅助剂制备颗粒天然橡胶（SK-NR），探讨海藻酸钠用量对SK-NR的凝固过程、力学性能、加工性能和热稳定性的影响。结果表明，颗粒胶是通过浓度梯度作用使凝固剂从外至里渗透凝固；与SCR-5相比，SK-NR的MH增大，T90缩短；随海藻酸钠用量的增加，SK-NR胶料的拉伸强度增大，撕裂强度变化不大，当海藻酸钠质量分数为1.0％时胶料的综合性能较好；RPA分析表明，海藻酸钠的加入会影响混炼胶的内耗；热稳定性分析表明，海藻酸钠在220~280 ℃间会裂解脱水，生成稳定的中间产物，导致SK-NR提前失重。     

魔芋葡甘聚糖对丝素蛋白纺丝液及其膜稳定性的影响

以魔芋葡甘聚糖(KGM)和丝素蛋白(SF)为原料,以KGM/SF纺丝液凝胶强度为响应值,溶胀温度、底物配比和凝胶时间为影响因子,进行响应面优化设计。同时,调节底物配比,采用静电纺丝技术制备纳米纤维膜,通过力学测试、差式扫描量热分析分别对纳米纤维膜的拉伸强度和热特性进行研究。结果表明,KGM有效的提高SF纳米纤维膜的强度及热稳定性;溶胀温度、底物配比和凝胶时间为纺丝液凝胶强度的显著影响因子,两两交互作用对其纺丝液凝胶强度影响极显著,其数值分别为49.87℃、84.41%和58.80 min时,模型预测纺丝液凝胶强度达到最大值828.231 g·mm。     

环境湿度对火麻单纤维力学性能的影响

火麻韧皮纤维束强度高,韧性好,其力学性能主要由单纤维决定。研究采用离析法从火麻韧皮纤维束中提取出单纤维,利用纤维微拉伸测试技术对其开展了力学测试,同时考虑了环境湿度对单纤维力学参数的影响。结果表明,环境湿度从20%增加到70%的过程中,火麻单纤维的弹性模量和抗拉强度随环境湿度的增加逐渐降低,断裂应变则随着环境湿度的增加而逐渐增加,其中,弹性模量从29.88 GPa下降至8.30 GPa,抗拉强度从427.32 MPa降至150.58 MPa,而断裂应变则从2.26%增加至2.93%。     

黄麻与亚麻的纤维性能比较

本文对黄麻、亚麻的纤维性能进行研究比较，从纤维性能的角度探讨黄麻纤维部分替代亚麻纤维的可行性。结果表明：黄麻纤维有可能部分替代亚麻纤维。     

Dietary fiber content of commonly fresh and cooked vegetables consumed in India

Legumes, leafy vegetables,roots and tubers, gourds and other vegetables were analyzed for total (TDF), soluble (SDF) and insoluble (IDF) dietaryfiber contents, both before and after cooking eitherby a conventional open-pan method or by pressurecooker. Data revealed a significant increase inSDF fraction with a concomitant decrease in the IDFfraction upon cooking by both the methods employed. Although the decrease in IDF matched the increase inSDF values in some cases, it was found to be more invegetables categorized as `other'. The dietary fiber values have also been reported on a fresh weight basis which may serve as a guideline for calculating dietary intake of eachcomponent by the consumer.     

几种新型天然纤维的性能分析与开发应用

分析了香蕉纤维、菠萝纤维和椰壳纤维的化学组成及物理机械性能，并介绍了它们的开发应用。     

苎麻麻条牵切工艺初探

通过对苎麻纤维长度及其分布，超长、倍长纤维对苎麻纺纱的不利影响的分析，提出了采用牵切提高苎麻纤维长度整齐度，减少超长、倍长纤维的加工技术。     

竹纤维性能及发展展望

竹纤维是现今市场上极具经济开发价值的新型纺织原料,分为天然竹纤维和再生竹纤维。本文对这两类竹纤维从结构特点、生产流程、性能差异等角度进行了论述,指出了目前市场存在的问题以及未来的发展方向。     

可食用野生蔬菜中纤维类物质的检测方法

依据GB/T 5009.88-2003食品中不溶性膳食纤维的测定(Determination of insoluble dietary fiber in foods)和GB/T 5009.10-2003植物类食品中粗纤维的测定(Determination of crude fiber in vegetable foods),并简化其操作步骤,对海南8种可食用野生蔬菜中的粗纤维和不溶性膳食纤维进行测定.结果表明,不同用量石油醚和α-淀粉酶对蔬菜中脂肪和淀粉进行前处理的作用不大.对测定结果几乎无影响;8种野生蔬菜中不溶性膳食纤维含量为1.5%～4.9%.粗纤维含量为0.7%～1.8%.     

Quality Improvement of Upland Cotton (Gossypium hirsutum L.)

Abstract

Quality of cotton can be defined through seed or fiber properties, but is most often associated with fiber properties that influence processing into yarn and textile products. Global competition in the production and consumption of cotton fiber combined with technological evolution of yarn manufacturing has spurred renewed efforts to enhance cotton fiber quality. Cotton fiber quality can be improved through genetics, crop management, and postharvest processing. Knowledge of the effects of fiber properties on processing and their inheritance, relationships, and environmental influences is necessary to formulate improvement strategies. Breeding to improve fiber quality has traditionally focused on enhancing measures of the longest fibers or fiber strength for ring yarn manufacturing systems. With the technological evolution of yarn manufacturing from solely ring-based spinning to predominately rotor and potentially in the near future air-jet spinning, needs for fiber profiles have been revised for these spinning systems. Successful rotor spinning requires high fiber strength for all yarn counts, along with fiber fineness for fine count yarns. The even more productive air-jet spinning requires a minimum, but uniform fiber length, fiber fineness, and to a lesser extent strong fiber. In contrast, ring spinning requires a minimum fiber length, fiber strength, and to a lesser extent fiber fineness. Breeders do not conduct direct selection for yarn properties because of impracti-calities, thus they select for fiber properties that influence processing, so-called indirect selection. The inherent environmentally induced variability in fiber properties presents challenges to enhance them through breeding or biotechnological approaches. Because variability in fiber properties is problematic to fiber processing, future-breeding and biotechnological approaches should simultaneously focus on enhancing fiber properties and reducing variation. This paper will review strategies to enhance fiber profiles through genetic approaches while ameliorating their variation.     

红麻韧皮部束纤维层的分离及纤维长度分布

采用亚氯酸钠一冰醋酸和草酸铵处理，将不同部位的红麻韧皮部束纤维进行分层，并测定各束纤维层的纤维细胞长度，探讨红麻韧皮部纤维细胞长度的分布规律。     

Effect of proccesing on dietary fiber content of cereals and pulses

Total dietary fiber (TDF), insoluble dietary fiber (IDF) and soluble dietary fiber (SDF) content of rice, wheat, sorghum, maize, ragi, bajra, whole grains of pigeonpea, chickpea, green gram and lentil as well as their dehusked split dhals were analyzed. Cereals except rice flours were made into chapati (unleavened bread), while rice and dhals were cooked in a pressure cooker. After the processing, IDF and SDF contents of these foods were also analyzed. Among the cereals, rice had the lowest TDF (4.1%) and wheat had the highest (12.5%). TDF content of whole pulses ranged from 15.8% in lentil to 28.3% in chickpea. IDF as % of TDF constituted 85 to 89% in whole pulses. Dehusking of pulses into dhals decreased the TDF and IDF contents significantly. Among the dhals, green gram dhal had the lowest (8.2%, 6.5%) and chickpea dhal (15.3%, 12.7%) had the highest TDF and IDF contents, respectively. Processing of cereals had no effect on their TDF and IDF contents, rith the exception of ragi, where a significant increase in TDF and IDF was observed. Cooking of dhals brought about a significant increase in their TDF and IDF contents.     

天然竹纤维与竹浆粘胶纤维的结构性能比较

竹纤雏有以竹材为原料制成浆粕，经纺丝加工而成的竹浆粘胶纤维；也有从竹材中以物理化学方法直接提取出的天然竹纤维，两种纤维因来源不同，故性能差异很大。本文对两种竹纤维的结构与性能进行了较全面的比较研究。研究结果表明：天然竹纤维具有优异的抗茵性能，夏季干爽舒适性好，热稳定性好，结构上属结晶度高、大分子排列紧密的典型的纤维素Ⅰ型结晶。竹浆粘胶纤维则由于纺丝过程而在性能上受到很大损伤，强力低、结晶度低、大分子排列较稀疏，回潮率高，属于与普通粘胶纤维相似的再生纤维素纤维。