THE FIBER MORPHOLOGY VARIATION OF TRIPLOID CLONE OF POPULUS TOMENTOSA CARR.AND ITS SUPPOSED HARVESTING AGE FOR THE PAPER INDUSTRY

The fiber morphology variation of triploid clone of Populus tomentosa Carr. and the supposed harvesting age for the paper industry were investigated in this paper. The results shows that in the first few years, 2-4 years for example, the fiber length at breast high grows faster than it does in the later years. But the standard deviation of distribution in fiber length at breast high in mature wood is larger than in the young tree. The technologically harvestable age of triploid clone of Populus tomentosa Carr., BL304 could be 4-7 year old to meet the requirement for paper industry. The distribution of fiber length become concentrated within an annual ring as the tree grows. The test results also show that the cloned poplar has a small Runkel ratio value (less than 0.4, generally about 0.3), and this ratio increases slightly with the tree grows.

Selection of Plus Tree Based on Growth Performance and Fiber Morphology Characteristics as Improved Sources for Propagation of <i>Eucalyptus camaldulensis</i>

One of the most successful techniques in planting trees is tree improvement in which trees with high qualities are selected for mass plantation. This study seeks to identify good properties of Eucalyptus camaldulensis through selective phases. Sixty Eucalyptus camaldulensis trees (30 ten-year-old and 30 five-year-old) were randomly selected through stratified sampling from two plantation sites in Kurdistan region, North of Iraq. The trees were examined for fiber morphology and quality parameters such as height, number of branches, diameter and straightness. In the first phase of property selection, sixteen trees with high rank in growth properties and fiber morphology were selected. In the final phase of selection, the selected trees were re-examined according to the number of properties and fiber morphology features and seven trees with the highest number of good parameters were chosen. The 7 selected trees had higher qualities in growth characteristics and fiber morphology compared with the other trees in the sample. This article reports on a selection method for E. camaldulensis trees through tree improvement techniques. The results of the study indicates that high genotype qualities were identified among both 5- and 10-year-old E. camaldulensis trees as the final selection consisted of three 5-year-old trees and four 10-year-old trees.

RESEARCH ON FIBER MORPHOLOGY AND PULPING PROPERTIES OF THE TRIPLOID OF PLPULUS TOMENTOSA FROM PLANTATION AT DIFFERENT AGES

The fiber morphology and pulping properties of triploid of populus tomentosa from plantation at different ages were investigated in the paper,also the main chemical compositions were determined. The results showed that the difference of chemical compositions is not significant, and the extractive contents become bigger in some sort with age, the difference of length weighted mean length of fiber also is not significant, and coarseness of fiber has trend of augment by degree, while the fines content increases obviously with age. That difference of pulping properties between chemical pulping (KP process and Soda-AQ process) and chemimechanical pulping (SCMP process and APMP process) is not significant, which is consistent with the analysis of chemical composition and fiber morphology. Considering comprehensively, the tree age of 5 years is better for paper making industry, also the mixed pulping with different ages of the triploid of populus tomentosa is feasible with steady pulp quality.

Effects of Ni catalyzer on growth velocity and morphology of SiC nano-fibers

Composite felts reinforced by both SiC nano-fibers(SiC-NFs)and carbon fibers were prepared at 1 273 K using Ni granules as catalyzers with different deposition time.SiC-NFs were deposited on the surface of the carbon fibers in situ by catalytic chemical vapor deposition(CCVD).The phase,microstructure and morphology of the fibers after electroplating and deposition were characterized by XRD,SEM and TEM.The results show that the SiC-NFs produced by CCVD are composed of single crystal of β-SiC.It is found that smaller nano-granules are more active as catalyzers.The resulting SiC-NFs appear more spindle-like and have a more homogeneous dispersion.The mass change of the samples before and after deposition shows that using more Ni granules results in a faster growth velocity of SiC-NFs.With the same electroplating time,the growth velocity of the SiC-NFs first increases and then decreases.At around 4 h,it reaches the maximum growth velocity,and it becomes nearly constant at around 8 h.After 8 h, the stable growth velocity of the electroplated Ni samples is faster than that of the conventional sample produced without catalyzers, because the SiC-NFs can improve the specific surface area and the activity of the surface.

Effect of Fiber Loading and Compatibilizer on Rheological, Mechanical and Morphological Behaviors

This study presents the composites prepared by melt blending based on high-density polyethylene, containing various amounts of kenaf fiber loadings and polyethylene-grafted maleic anhydride (PE-g-MA) in an internal mixer were prepared and investigated. Fourier transform infrared spectroscopy was used to characterize both untreated and treated ke- naf fibers. A rheological study of the composites showed a high complex viscosity and dynamic shear storage modulus between untreated and treated composites and composites with compatibilizer. A mechanical test showed that the ten- sile strength and tensile modulus were optimal with 20% fiber loading but decreased with 30% fiber loading for both the untreated and treated composites. The composite with PE-g-MA showed an improved mechanical strength. This phenomenon is due to an increase in the interfacial adhesion between the fiber and matrix leading to an improvement in the compatibility of the blend. Treatment of the kenaf fiber improved in the mechanical and impact strengths in com- parison to the untreated kenaf composites. This behavior was supported by a morphology analysis of the fractured sur- faces revealed that strong interfaces were formed on addition of the compatibilizer.

Morphology and Thermal Behavior of Polypropylene/Easily Hydrodegraded Polyester Blend Fibers

Ultrafine polypropylene fibers are prepared frompolypropylene/easily hydro - degraded polyester （PP/EHDPET） blend fibers, in which file EHDPET compo-nent is degradable by treating with NaOH - H2O solu-tion. We investigated the morphology of PP/EHDPETblend fibers before and after stretching and alkalinehydrolysis. Then thermal behavior of the blend has alsobeen studied.

Corn Husk Fiber Preparation and Morphology with Alkali Treatment

The corn husks were usually discarded as useless materials,after alkali treatment from which the corn husk fiber was obtained. The corn husk fiber included half degumming corn husk bundle fiber and corn husk single fiber. This study found that corn husk single fiber was a kind of cellulose fiber,and was obtained with the fully alkali treatment technique,the process of which was NaOH concentration 0.15 g/mL,temperature at 80℃,and reaction time about 2.5 h. The morphologies of corn husk single fibers presented nature convolutions along with the fiber axis. They were closed at both ends,and they had a pentagram cavity and oval-shaped crosssection. They were flat shape,the fineness of the fibers was close to cotton fiber,and the mechanical properties of the fibers were similar to hemp fiber. So the corn husk fibers could be predicted that they could be used in textile industry because their properties were very close to cotton fiber or flax fiber.

PFI磨预处理提高桉木浆纤维反应活性的研究

采用PFI磨对桉木漂白化学浆进行预处理后,以丙烯酰氯为酯化试剂,在球磨机中进行酯化反应,通过纤维质量分析仪、光学显微镜、X射线衍射(XRD)和傅里叶红外光谱(FT-IR)对纤维的形貌和结构进行了分析,并进一步考察了酯化条件对纤维素反应活性的影响。研究结果表明:随着PFI磨转数的增加,纤维长度、纤维宽度减小,细小纤维比例显著提高,由19.86%增大至38.47%。经PFI磨打浆后,纸浆纤维表面纤丝化明显,其结晶区域部分遭破坏,结晶度由72.7%降低至66.9%;XRD结果表明:反应过程中酯化产物的结晶结构发生了改变。FT-IR结果表明:PFI磨解纤维与丙烯酰氯经球磨发生酯化反应得到丙烯酰基纤维素。酯化产物的取代度(D_(S))随着PFI磨转数的增加而增大;与未经预处理纤维相比,反应产物的D_(S)明显增加,最高可达2.38,此时的反应条件为PFI磨预处理24000 r,纤维素与丙烯酰氯的物质的量比1∶6,球磨反应时间48 h。

不同生长期香菇培养料中木质纤维素的变化特征

为探究不同生长期香菇培养料中木质纤维素的变化特征,促进其高效降解利用,以香菇培养料为研究对象,采用范式抽提法、X-射线衍射法、傅里叶变换红外光谱法和光学显微成像法对各生长期香菇培养料的木质纤维素含量、纤维素结晶度、木质纤维素相关的官能团和纤维形态变化进行分析。结果表明,随着香菇生长进程的推进,木质纤维素各组分含量显著下降,纤维素生殖生长阶段降解较多,半纤维素、木质素、综纤维素降解具有明显的阶段性,进入转色后降解速度加快。二茬菇时纤维素、半纤维素、木质素和综纤维素含量分别比原料降低了34.73%、61.58%、57.15%、42.33%。各生长期的香菇培养料均具有典型的纤维素X射线衍射特征,纤维素结晶区被破坏,典型衍射峰的结晶度持续减少。傅里叶变换红外光谱显示,木质纤维素的红外光谱特征官能团主要吸收峰的位置未发生改变,但振动强度减弱,与木质纤维素各组分的降解利用规律一致;特征峰比值I1723/I1510、I1383/I1510、I1157/I1510呈现不断减少趋势,而I897/I1510在转色和一茬菇呈增大趋势,表明香菇对木质纤维素各组分的降解程度不同,该生长期木质素相比纤维素有着更快的降解速率。纤维长度及宽度总体上呈现降低的趋势,二茬菇与其他生长期存在显著性差异。经显微镜观察,二茬菇纤维壁及内腔遭到破坏,明显区别于原料。因此,香菇对培养料木质纤维素具有较强的持续的降解作用,可显著降低木质纤维素含量,破坏纤维素结晶区,使得红外光谱吸收峰及纤维形态发生改变。

香菇菌糠中木质纤维素的挤压降解及结构表征

为开发香菇(Lentinus edodes)菌糠的新型加工处理方式,促进其高效转化利用,以香菇菌糠为研究对象,采用范式抽提法、傅里叶变换红外光谱法、X-射线衍射法和光学显微成像对经挤压处理香菇菌糠的木质纤维素含量、木质纤维素官能团、纤维素相对结晶度和纤维形态变化进行分析。结果表明,香菇菌糠经过挤压处理后木质纤维素各组分均有不同程度减少,40%水分挤压和50%水分挤压后木质纤维素含量分别降低了13.863%、11.264%,纤维素含量分别降低了19.003%、16.630%,综纤维素含量分别降低了17.357%、11.343%,木质素含量分别降低了6.574%、11.099%,纤维素相比半纤维素、木质素呈现出更快的降解速度;与50%水分挤压相比,40%水分挤压对半纤维素、综纤维素的降解作用更显著,降解率分别提高了12.131%、6.783%。傅里叶变换红外光谱显示,木质纤维素的红外光谱特征官能团主要吸收峰的位置未发生改变,但吸收峰特征及强度发生变化,表明挤压处理对香菇菌糠中木质纤维素各组分有降解作用,其中半纤维素在低水分条件下更易发生降解,与木质纤维素各组分的挤压降解规律一致。挤压前后的香菇菌糠均具有典型的纤维素X射线衍射特征,挤压后纤维素结晶区被破坏,40%水分挤压和50%水分挤压后纤维素相对结晶度分别降低了21.10%、18.00%。纤维长度、宽度及长宽比呈现出降低趋势,经显微镜观察,挤压后香菇菌糠纤维壁及内腔进一步遭到破坏,膨松状态片状结构明显增多增大。因此,挤压处理可有效降解香菇菌糠木质纤维素,破坏其生物质结构,使得红外光谱吸收峰、纤维素结晶度及纤维形态发生改变,其中,40%水分挤压的降解作用更佳。

不同生长阶段香菇栽培料木质纤维素降解利用研究

为深入了解香菇生长发育过程中栽培料木质纤维素的变化,对不同生长阶段香菇栽培料中木质纤维素含量及其相关降解酶活性进行了测定,利用傅里叶变换红外光谱(FTIR)、X-射线衍射法(XRD)和显微镜观察研究了木质纤维素微观结构分子基团、纤维素相对结晶度(CrI)和纤维表面形态的变化。结果表明,在香菇生长发育过程中,栽培料中的纤维素、半纤维素和木质素含量显著下降,木质纤维素含量(w,后同)由85.27%降低至52.23%,其与相应的降解酶系活性负相关,木质纤维素降解与纤维破坏程度呈现一定的相关性。FTIR结果显示,不同生长阶段香菇栽培料中木质纤维素特征官能团峰值发生变化,木质素降解速率高于半纤维素、低于纤维素。随着香菇的生长发育,栽培料中CrI显著降低,纤维素晶体结构受到了一定程度的破坏。结果表明,香菇首先利用栽培料中非木质纤维素组分供菌丝生长,同时分泌胞外降解酶破坏纤维结构,将大分子组分降解为小分子组分,从而满足其生长所需,高木质纤维素降解酶活性对应高木质纤维素降解率。该研究结果可为促进香菇栽培料中木质纤维素的降解利用提供依据。

The Morphology and Properties of the X-ray Shielding Fibers

The morphology,mechanical and dynamic mechanicalproperties and shielding efficiency of the novel X-rayshielding fibers were analysed.The results show that thestructure defects which exist in as-spun fibers are obvi-ously reduced in the drawn fibers.The tensile strengthand the elongation at break of drawn fibers decrease withthe increase of the shielding agent content and the tensilestrength increases with the increase of the drawn-foldof the fibers.On the E’-T curves,as the shielding agentcontent increases,there is first an increase,then a de-crease in the E’value above 60% of the shielding agent.Their thermal properties also change evidently.Theshielding efficiency of their nonwoven fabrics is obvious.

榔榆木质部细胞构造特征的季节变化规律研究

为了探究榔榆木质部形成中细胞形态与壁层组分变化规律,以1个生长季内木质部细胞产生过程为主线,联合解剖学技术与光谱学技术,初步研究了木质部细胞形态、细胞尺寸及细胞壁主要化学组成的变化规律。结果表明4月出现2排早材管孔,以单管孔为主,5月开始大量产生木纤维细胞,纤维细胞壁厚,直至9月形成宽约2 mm的木质部;导管与木纤维细胞从4—6月处于伸长阶段,大小随后略有降低;2类细胞的直径则呈不同的季节变化规律;导管细胞壁纤维素和半纤维素的沉积过程在季节内稳定;而木纤维细胞中纤维素和半纤维素的沉积具有季节差异,生长季早期相对含量较低,晚期相对含量明显增加,说明2类细胞间主要组分沉积存在不同步性。

日本古代写经纸样本的特性分析与显微形态研究

日本历史上曾有着非常悠久的写经传统,留下了大量古写经。这些古写经不仅可以通过传统的文献学方法进行年代鉴别,还可以通过科学手段对纸张原料成分、加工方式及微观形态等进行分析。本研究通过对《古写经遗影》和《古写经聚英》2本古写经样本册中收录的81件古纸样本进行测试分析,总结了日本不同历史时期写经纸样本在纤维成分、纸张厚度、帘纹密度、纸面特征及加工方式等方面可能存在的共性和趋势,为研究日本历代写经纸制作工艺、古写经的年代鉴别提供纸张信息方面的参考。

玄武岩纤维对3D打印混凝土力学性能的影响

为探究玄武岩纤维对3D打印混凝土力学性能的影响,设计0%、0.25%、0.50%、0.75%和1.00%共5种不同玄武岩纤维掺量,通过单轴压缩、三点弯曲和层间双剪试验分析玄武岩纤维掺量对3D打印混凝土力学性能的影响,并利用双目倒置金相显微镜和扫描电子显微镜从微观形貌层面分析玄武岩纤维增强混凝土力学性能的作用机制。研究结果表明:掺加玄武岩纤维可显著提升3D打印混凝土结构的力学性能。随着纤维掺量的增加,抗压和层间抗剪强度呈现出先增加后减小的趋势,掺量为0.50%时共同达到最优,相较于未掺入玄武岩纤维的混凝土分别提高了28%和61%;抗折强度则随着纤维掺量增加一直增加,掺量为1.00%时效果最佳,相较于未掺入玄武岩纤维的混凝土提高了21%。打印材料力学性能存在各向异性,沿Z方向加载时抗压和抗折强度最高,Y方向最低;随着纤维掺量增加,力学性能各向异性逐渐增大。结合试验结果和电镜扫描结果可知,玄武岩纤维优异的抗拉性能够抑制裂缝的产生与扩展,从而提升3D打印混凝土结构的整体力学性能。

聚乳酸异形纤维熔融纺丝及性能研究

以聚乳酸(PLA)切片为原料,采用异形喷丝板,通过熔融纺丝、拉伸两步法制得PLA异形截面纤维。通过对PLA切片的DSC热分析确定纤维纺丝成形温度,并用显微镜分析了纤维的截面形态,研究了不同拉伸倍数下PLA纤维性能。结果表明,PLA纤维为类十字形异形截面纤维,相对径向异形度为37%,纤维表面平滑,且有明显的棱状凸起。拉伸倍数越大,断裂强度和取向因子都增大,而断裂伸长率下降。

一种集成电路电容适用的碳纤维改性复材制备及性能

为了提升集成电路电容用复合材料的综合性能,对比分析了碳纤维(CF)、Ni(OH)_(2)改性碳纤维CF-Ni(OH)_(2)和聚多巴胺改性碳纤维CF-PNi的表面形貌、化学结构、润湿性能和力学性能。结果表明,原始CF表面存在深度不一的加工沟槽、粗糙度较大,当经过Ni(OH)_(2)和聚多巴胺改性处理后,碳纤维表面沟槽基本消失,表面粗糙度减小。改性CF相较CF与树脂(EP)的接触角都有不同程度减小,与树脂接触角从大至小顺序依次为:CF、CF-Ni(OH)_(2)、CF-PNi;当采用Ni(OH)_(2)对CF进行改性后,CF-Ni(OH)_(2)/EP的弯曲强度F_(s)、弯曲模量F_(m)、层间剪切强度ILSS和横向拉伸强度Hl相较CF有明显提升,采用聚多巴胺进一步对CF-Ni(OH)_(2)进行改性处理后,CF-PNi/EP的F_(s)、F_(m)和Hl会相较CF-Ni(OH)_(2)/EP进一步提升,而ILSS变化幅度不大。

二化螟盘绒茧蜂茧丝纤维的形态结构与理化性能

本文通过扫描电镜(SEM)、氨基酸分析、傅立叶红外光谱(FTIR)、X射线晶体衍射(XRD)和热重分析(TG)等技术对二化螟盘绒茧蜂Cotesia chilonis茧丝纤维的微观形态、氨基酸类别与组成、二级结构和热稳定性等作了分析。结果表明,二化螟盘绒茧蜂的茧丝纤维表面较为粗糙,直径为1.89±0.04μm。茧丝纤维主要由碳(60.67%)、氮(21.17%)和氧(17.22%)等元素组成,其丝蛋白主要成分包括天冬氨酸/天冬酰胺、丝氨酸和丙氨酸等;蛋白二级结构主要为β-折叠;其峰值降解温度为332.27℃±2.58℃。本文研究揭示了二化螟盘绒茧蜂茧丝纤维的结构特征与理化性能,为拓展该蜂的应用领域、开发性能优越的非蚕丝蛋白以及设计改造新型丝蛋白纤维提供基础。

纤维性能对纸张水蒸气阻隔性能的影响

本研究利用不同种类、不同程度打浆处理及硅烷化改性的纸浆纤维,制备物化性能不同的纸张,调控纸张的三维孔隙结构,从纤维的物理性能和化学疏水改性对纸张结构影响的角度,探讨纤维性能(打浆度、纤维长度及分布、保水值、纤维形貌和亲/疏水性等)对纸张水蒸气阻隔性能的影响。结果表明,纸张的水蒸气阻隔性能受纤维打浆度和亲/疏水性的影响较大。测试条件(23±0.5)℃、相对湿度(50±1)%时,打浆度从13.5°SR增至90°SR的未漂化学针叶木浆制备的定量60 g/m^(2)纸张的水蒸气透过率从954.5 g/(m^(2)·d)降低至93.77 g/(m^(2)·d);测试条件为(23±0.5)℃、相对湿度(75±1)%时,疏水改性纤维纸张比未改性纤维纸张的水蒸气透过率降低了11.6%,纸张的水蒸气透过率受疏水改性纤维配抄比例的影响较大。

转BtCry1Ac基因对107杨材性的非预期影响

为了探究外源BtCry1Ac基因对107杨材性性状产生的非预期影响,以转BtCry1Ac基因107杨2个株系(ECA1和ECA2)和野生型株系(WT)为材料,对其木材化学组分、物理和力学性质及纤维形态指标进行了定量测定。结果显示:BtCry1Ac基因的转入使107杨木材材性发生了非预期变化,具体表现为ECA1和ECA2的纤维素、灰分、苯醇抽出物及1%NaOH抽出物组分含量均显著低于WT(P<0.05);ECA1和ECA2的气干干缩性、全干干缩性显著低于WT(P<0.05),且ECA1和ECA2的气干密度、全干密度显著高于WT(P<0.05);ECA1和ECA2的冲击韧性、抗弯强度、抗弯弹性模量和顺纹抗压强度均显著高于WT(P<0.05);ECA1和ECA2的纤维长度显著低于WT(P<0.05)。总体表现为转基因株系的木材有着更小的干缩性,更高的密度和强度,其材性发生了非预期性改变,研究结果为转基因杨树的推广与应用提供了参考。