tensile properties of earlywood and latewood from loblolly pine using digital image correlation

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异叶南洋杉木材的物理力学性质研究

摘要：采取常规方法对异叶南洋杉木材物理力学性质进行了测定研究，试验结果表明，异叶南洋杉的气干密度、基本密度、绝干密度分别为０．４８０、０．４６６、０．４５７６ｇ·ｃｍ－３；径向、弦向和体积干缩率平均值
分别为２．７３％、２．５％和１１．２５％；干缩系数分别为０．１１６％、０．０９５％和０．４６％；端面、径面、弦面等三个
中图分类号：Ｓ７８１；Ｓ７９１．１３
文献标识码：Ａ
文章编号：１００１２１１７（２０２０）０１００１９０３
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良凤江国家森林公园，该森林公园位于南宁市南郊，距市区７ｋｍ，地处北回归线以南，属南亚热带
收稿日期：２０１９１１０３基金项目：南宁树木园优质用材树种科研项目培育与深化。作者简介：张振林（１９６８－），男，广西北流人，高级工程师，主要从事林业经营管理与林业科技研究推广工作。
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翠柏木材解剖性质和结晶度的径向变异及化学性质

ＣｉｅｅＡｃｄｍｙｏｏｅｔ）／ｏｒａｏｏｔｅｓＦｒｓｒｉｅｓｙ－２１４４）一９５ｈｎｓａｅｆＦｒｓｒ／ＪｕｎｌｆＮｒａｔｏｅｔＵｎｖｒｉ．０２．０（．４ — ４ｙｈｙｔ
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Ｑｎｆｎ（ｏｔａｔｏｅｔｎｖｒｔ）Ｌａｈｎｘ（ｅｅｒｈＩｓｔｔｏｅｏｒｅＩｓｃ，ｈｎｓｃｄｍｆｏ－ｉｇｇＮｒｅｓＦｒｓｙＵｉｓｙ：ｉＳｅｇｉＲｓａｃｔｕｆｓｕｃｅｔＣｉｅＡａｅｙｏｒｅｈｒｅｉｏｎｉｅＲｎｓｅＦｅｔ）ｈＪｎｔ（ｏｔａｔｏｅｔＵｉｅｓｙ；ＷａｇＸａｑｎ，Ｌｕ（ｅｅｒｈＩｓｔｅｏＲｓｕｃｎｅｔｓｙ；ＳｉｉｇａＮｒｅｓＦｒｓｙｎｖｒｔ）ｒａｏｈｒ，ｉｎｉｉｇｉＫｎＲｓａｎｔｕｆｅｏｒｅＩｓｃｓｏｃｉｔ，
１ｉｎｅｃｒｗｈｒｎｆＣｆ凹ｄｕｕｒｌｐｓＫｒ．ｉａｇｉｇＣｕｔｉｔｉａｈｇｏｔｉｇｏａ０ｒｓｎｗｏｅｉＵｚｎＣｈｎｎｎｏｎｙ．ＹｎｎＰｏｉｃ．Ｔｅｃｅｃｌｐｏｅｉｓｎｙｕａｒｖｎｅｈｈｍｉａｒｐｒｅｔｏｏｄｗｒｅｅｍｉｅ．Ｒｅｕｔｉｄｃｔｄｔａｒｃｅｄｍｏｐｏｏｉａｅｔｒｓｅｌｗａａｉｎｒｓａｌｉｎｒａｅｆｗｏｅｅｄｔｒｎｄｓｌｎｉａｅｈｔｔｈｉｒｈｌｇｃ１ｆａｕｅ．ｃｌｓａｌｒｔａｄｃｔｌｎｔｉｃｅｓｄｌｏｙｉｙｗｉｎｒａｉｇａｅｏｒｗｈｒｎｓｎｅｄｄｔｅｓｂｅａ０５ｙａｓｔｉｅｅｓｇｆｇｏｔｉｇ．ａｄｔｎｅｏｂｔｌｔ２ —２ｅｒ：ｍｉｒｆｒｌｒａｇｅ．ａｕｌｅｒａｅｎｈｎａｃｏｂｉａｎｌｇｄａｙｄｃｅｓｄａｄｉｌｒｌａｓｅｄｄｔｅｓａｌｔ０２ｅｒ：ｗｉｉｓｅｐｏｏｔｎｓｏｅｎｕｏｖｏｓｃａｇ．Ｃｏｒｌｔｎａａｙｉｏｒｓｌｏｔｎｅｏｂｔｂｅａ — ５ｙａｓｈｌｔｕｒｐｒｏｈｗｄａｎｂｉｕｈｎｅ２ｅｓｉｒｅａｉｎｌｓｓｆｅ．ｏｙ

210967473_异叶南洋杉人工林木材生材性质研究

第48卷第1期2023年1月㊀林㊀业㊀调㊀查㊀规㊀划Forest Inventory and PlanningVol.48㊀No.1Jan.2023doi:10.3969/j.issn.1671-3168.2023.01.003异叶南洋杉人工林木材生材性质研究邓福春1,罗青竹2,刘衡2,韦鹏练2,符韵林2(1.广西壮族自治区南宁树木园,广西南宁530031;2.广西大学林学院,广西南宁530004)摘要:为合理利用异叶南洋杉人工林木材,通过排水法㊁质量法和数值法对异叶南洋杉人工林的生材性质展开研究,结果表明,异叶南洋杉人工林木材树皮体积百分率㊁质量百分率㊁生材密度㊁基本密度和生材含水率的平均值分别为11.39%㊁13.78%㊁0.842g/cm3㊁0.394g/cm3和121.43%㊂随异叶南洋杉树高的增加,树皮体积百分率和质量百分率总体呈增大趋势;生材密度和基本密度总体呈下降趋势;生材含水率总体呈先升高后降低的趋势㊂以期为异叶南洋杉人工林木材的合理利用提供数据支持和理论支撑㊂关键词:异叶南洋杉;生材密度;基本密度;树皮体积百分率;生材含水率;树皮质量百分率中图分类号:S781;S791.3㊀㊀文献标识码:A㊀㊀文章编号:1671-3168(2023)01-0013-05引文格式:邓福春,罗青竹,刘衡,等.异叶南洋杉人工林木材生材性质研究[J].林业调查规划,2023,48(1):13-17.doi:10.3969/j.issn.1671-3168.2023.01.003DENG Fuchun,LUO Qingzhu,LIU Heng,et al.Green Wood Properties of Araucaria heterophylla Plantation[J].Forest Inventory and Planning,2022,48(1):13-17.doi:10.3969/j.issn.1671-3168.2023.01.003Green Wood Properties of Araucaria heterophylla PlantationDENG Fuchun1,LUO Qingzhu2,LIU Heng2,WEI Penglian2,FU Yunlin2(1.Nanning Arboretum of Guangxi,Nanning530031,China;2.College of Forestry,Guangxi University,Nanning530004,China) Abstract:In order to make reasonable use of Araucaria heterophylla plantation wood,this paper used drainage method,mass method and numerical method to study the green wood properties of Araucaria het-erophylla plantation.The results showed that the average bark volume percentage,mass percentage, green wood density,basic density and green wood moisture content of Araucaria heterophylla plantation were11.39%,13.78%,0.842g/cm3,0.394g/cm3and121.43%,respectively.With the increase of the tree height,the bark volume percentage and mass percentage showed an upward trend;the green wood density and basic density showed a downward trend;the green wood moisture content increased first and then decreased.This research provided data and theoretical support for the rational use of Araucaria heterophylla plantation wood.Key words:Araucaria heterophylla;green wood density;basic density;bark volume percentage;green wood moisture content;bark mass percentage收稿日期:2021-09-01.基金项目:广西大学科研项目(BB33600114).第一作者:邓福春(1970-),男,广西邕宁人,高级工程师.研究方向为林业经营管理.林业调查规划㊀㊀异叶南洋杉(Aracaria heterophylla ),属于南洋杉科(Araucariaceae)南洋杉属(Araucaria Juss)常绿乔木,树干通直,树姿优美,是世界上著名的观赏树种之一[1]㊂异叶南洋杉原产于大洋洲㊁南美洲以及太平洋诸岛等热带㊁亚热带地区[2],上世纪以来,我国北京㊁上海㊁广东及广西等地引种栽培用作盆栽和庭园树[3]㊂目前,关于异叶南洋杉的研究,主要集中于引种㊁培育㊁繁殖㊁植物叶挥发油的化学成分等方面[4-6],但关于异叶南洋杉木材生材性质及其木材利用研究鲜有报道㊂木材生材性质是木材性能的重要指标,对木材合理利用有着重要意义㊂为合理利用异叶南洋杉人工林木材,对异叶南洋杉人工林的生材性质展开研究,以期为异叶南洋杉人工林木材的合理利用提供数据支持和理论支撑㊂1材料与方法1.1样木采集3株异叶南洋杉样木均采集于广西壮族自治区南宁市树木园㊂样木采集依据GB /T 1927 2009[7]进行,在林区内选定3棵具有代表性的样木,测量并标定北向后伐倒,分别在树高0㊁1.3㊁3.3㊁5.3㊁7.3㊁9.3m 等(至树干直径小于6cm 为止)处截取厚5cm 的圆盘(表1)㊂圆盘截取后,立即用保鲜膜密封待用㊂表1㊀样木采集记录Tab.1㊀Collection record of test wood1-3 5.3~7.3223.122.91-59.3~11.3220.419.81-713.3~15.3215.715.6231.022.68.802-1 1.3~3.3227.226.62-3 5.3~7.3224.724.42-59.3~11.3220.920.42-713.3~15.3214.914.5333.924.25.553-1 1.3~3.3230.029.83-3 5.3~7.3226.525.33-59.3~11.3221.620.93-713.3~15.3216.115.43-917.3~19.329.39.21.2测定方法1.2.1树皮率测定树皮率包括树皮体积百分率和树皮质量百分率㊂其中树皮体积百分率指树皮体积与树干部位树皮和木质部体积之和的比值,树皮质量百分率指树皮质量与树干部分树皮和木质部质量之和的比值[8]㊂1)树皮体积百分率测定对于形状规则的圆盘,树皮体积的测量方法是用直尺测出圆盘的带皮直径(R 皮)和去皮直径(R 木),每个圆盘测量4次,分别为南北㊁东西㊁东北和西南方向,再测出圆盘的高(H ),计算时分别取平均值求出圆盘带皮和去皮的体积;对于形状不规则的圆盘,在测量南北㊁东西㊁东北和西南方向的基础上,增加测量长径和短径方向,然后求其平均值㊂树皮体积百分率(V )计算公式为:V =πR 2皮H -πR 2木HπR 2皮Hˑ100%(1)2)树皮质量百分率测定树皮质量百分率(M )的测量方法为测出圆盘的带皮重量(G 皮)和去皮重量(G 木),其公式为:M =G 皮-G 木G 皮ˑ100%(2)1.2.2木材密度测定1)生材密度测定将圆盘制成15mm ˑ15mm ˑ15mm 的小试样,测出小试样的生材重量(W 生),利用排水法测得生材体积(V 生);将圆盘南向㊁北向由内向外分为髓心㊁中间以及边材3个不同部位,每个方向各取6个小试样用于分析生材密度径向变化规律㊂木材生材密度(ρ1)计算公式为:ρ1=W 生V 生ˑ100%(3)2)基本密度测定测定基本密度所用试样和测定生材密度所用试样相同,将测定重量㊁体积的小试样放入烘箱中,保持(103ʃ2)ħ烘干至恒重,得到重量(W 干)㊂木材基本密度(ρ2)计算公式为:ρ2=W 干V 生ˑ100%(4)1.2.3生材含水率测定生材含水率的测定方法与生材密度的测定方法一致,含水率(C )计算公式为:㊃41㊃第48卷邓福春等:异叶南洋杉人工林木材生材性质研究C=W生-W干W生ˑ100%(5)2结果与分析2.1树皮率变化异叶南洋杉人工林木材树皮体积百分率㊁质量百分率与树高的关系如图1所示㊂图1㊀异叶南洋杉树皮体积百分率和质量百分率变化情况Fig.1㊀Changes of bark volume percentage andmass percentage of Araucaria heterophylla㊀㊀随树高增加,异叶南洋杉人工林木材树皮体积百分率总体呈增大趋势㊂在树高0.3~7.3m处,树皮体积百分率变化较小,说明这部分木材的生长趋于稳定;在树高7.3~15.3m处,树皮体积百分率逐渐增大,但增大幅度较小,说明这部分木材生长较快;当树高超过15.3m后,树皮体积百分率明显增大,说明树梢处的木材生长最快㊂随树高增加,异叶南洋杉人工林木材树皮质量百分率的变化趋势和树皮体积百分率变化几乎一致,总体呈增大趋势,树干基部树皮质量百分率最低,为12.52%,梢部树皮质量百分率最高,为16.41%㊂异叶南洋杉人工林木材树皮体积百分率和质量百分率平均值分别为11.39%㊁13.78%㊂有研究表明,其树皮可以用于提取松脂[6],因此,对于树梢处树皮体积百分率和质量百分率较高的木材,可考虑用于提取松脂,使异叶南洋杉人工林木材得到合理利用㊂2.2密度变化2.2.1生材密度统计异叶南洋杉人工林木材生材密度的径向变化及随树高变化,如图2所示㊂图2㊀异叶南洋杉生材密度的径向变化及随树高变化情况Fig.2㊀Radial variation of green wood density withtree height of Araucaria heterophylla㊃51㊃第1期林业调查规划㊀㊀异叶南洋杉人工林木材生材密度南向和北向的径向变化规律基本一致,均是自边材向内先减小后增大,在髓心部位生材密度最大,分别为0.949 g/cm3㊁0.897g/cm3,在中间部位生材密度最小,分别为0.802g/cm3㊁0.847g/cm3㊂随树高增加,异叶南洋杉人工林木材生材密度总体呈下降趋势,但从局部看,在树高7.3~9.3m 和树高13.3~15.3m处生材密度略微上升㊂在树干基部异叶南洋杉人工林木材的生材密度最大,为0.959g/cm3,在树高11.3m处最小,为0.734g/cm3㊂异叶南洋杉人工林木材平均生材密度为0.842 g/cm3,相较于观光木㊁格木㊁黄果厚壳桂㊁琼楠及大花序桉等木材[9-14],其生材密度较低㊂2.2.2基本密度统计异叶南洋杉人工林木材基本密度的径向变化及随树高的变化,如图3所示㊂图3㊀异叶南洋杉基本密度的径向变化及随树高变化情况Fig.3㊀Radial variation of basic density withtree height of Araucaria heterophylla ㊀㊀异叶南洋杉人工林木材生材密度北向和南向的径向变化规律基本一致,均是自边材向内逐渐增大,在髓心部位基本密度最大,分别为0.405g/cm3㊁0.399g/cm3,在边材部位基本密度最小,分别为0.461g/cm3㊁0.437g/cm3㊂随树高增加,异叶南洋杉人工林木材基本密度总体呈下降趋势,但从局部看,在树高5.3m和树高15.3~19.3m处基本密度略微上升㊂在树干基部异叶南洋杉人工林木材的生材密度最大,为0.492 g/cm3,在树高13.3m处最小,为0.359g/cm3㊂异叶南洋杉人工林木材平均基本密度0.394 g/cm3,相较于观光木㊁格木㊁黄果厚壳桂㊁琼楠及大花序桉等木材[9-14],其基本密度较低㊂2.3生材含水率统计异叶南洋杉人工林木材生材含水率的径向变化及随树高的变化,如图4所示㊂图4㊀异叶南洋杉生材含水率的径向变化及随树高变化情况Fig.4㊀Radial variation of green wood moisture content with tree height of Araucaria heterophylla㊃61㊃第48卷邓福春等:异叶南洋杉人工林木材生材性质研究㊀㊀异叶南洋杉人工林木材生材含水率南向和北向的径向变化规律基本一致,均是自边材向内逐渐降低,在边材部位生材含水率最大,为121.58%,在髓心部位生材含水率最小,为113.12%㊂北向平均生材含水率为117.21%,南向为122.61%,南向生材含水率大于北向㊂随树高增加,异叶南洋杉人工林木材生材含水率总体呈先升高后降低的趋势,但从局部看,在树高0.3~3.3m㊁5.3~9.3m以及11.3~15.3m处木材生材含水率升高,在树高3.3~5.3m㊁9.3~11.3m 以及15.3~19.3m处降低㊂在树高9.3m处异叶南洋杉人工林木材的生材含水率最大,为158.73%,在树高1.3m处最小,为97.09%㊂异叶南洋杉人工林木材平均生材含水率为121.43%,相较于观光木㊁格木㊁黄果厚壳桂㊁琼楠及大花序桉等木材[9-14],其生材含水率较高㊂3结论为合理利用异叶南洋杉人工林木材,对异叶南洋杉人工林的生材性质展开研究,结果表明,随树高增加,异叶南洋杉人工林木材树皮体积百分率和质量百分率总体均呈增大趋势,平均值分别为11.39%㊁13.78%;异叶南洋杉人工林木材生材密度南向和北向均是自边材向内先减小再增大,在髓心部位生材密度最大,随树高增加,生材密度总体呈下降趋势,平均值为0.842g/cm3;异叶南洋杉人工林木材基本密度北向和南向均是自边材向内逐渐增大,随树高增加,木材基本密度总体呈下降趋势,平均值为0.394g/cm3;异叶南洋杉人工林木材生材含水率南向和北向均是自边材向内逐渐降低,随树高增加,生材含水率总体呈先升高后降低的趋势,平均值为121.43%㊂参考文献:[1]中国植物志编委会.中国植物志(第49卷第3分册) [M].北京:科学出版社,1998.[2]白嘉雨,周铁烽,侯云萍.中国热带主要外来树种[M].昆明:云南科技出版社,2011.[3]臧德奎,徐晔春.中国景观植物应用大全(木本卷) [M].北京:中国林业出版社,2015.[4]张宏达.种子植物系统学[M].北京:科学出版社, 2006.[5]危孝棋,刘芳,林斌.异叶南洋杉根插繁殖技术研究[J].林业科技通讯,2004(6):10-11.[6]黄儒珠,檀东飞,张建清,等.3种南洋杉科植物叶挥发油的化学成分[J].林业科学,2008,44(12):99-104. [7]全国木材标准化技术委员会.木材物理力学试材锯解及试样截取方法:GB/T1927 2009[S].北京:中国标准出版社,2009.[8]李坚.木材科学研究[M].北京:科学出版社,2009.[9]邱炳发,石敏任,蒙好生,等.观光木的生材性质研究[J].福建林业科技,2011,38(2):95-98,106. [10]林凡,刘晓玲,范玮琳,等.33年生格木人工林生材性质研究[J].陕西林业科技,2015,4(5):5-9. [11]陆湘云,刘晓玲,韦鹏练,等.黄果厚壳桂木材生材性质[J].广西林业科学,2019,48(2):269-272. [12]施福军,刘晓玲,韦鹏练,等.琼楠木材生材性质研究[J].森林工程,2019,35(4):39-42. [13]刘鑫,刘衡,汪深洋,等.17年生大花序桉生材性质的研究[J].江西农业学报,2020,32(7):45-49. [14]覃卫星,刘衡,黎巍,等.29年生大花序桉生材性质的研究[J].江西农业学报,2020,32(6):52-56.责任编辑:陈旭校㊀㊀对:陈旭㊃71㊃第1期。

刺槐心材腐朽菌的鉴定及其生物学特性

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ＩｅｔｉａｉｎａｄＢｏｏｉａａｔｒｔｓｏｃｓａｔｏｔｎｉＧａｏｉｇｄｎｉｃｔｎｉｌｇｃＣｈｒｃｅｉｉｆＬｏｕｔＨｅｒｗｏｄＲｏｆｏａｌｓｃＦｕｇ／ｏＧｕｐｎ，Ｘｉｅ。ＺｅｇＹｎｎ．ｎＷｎｈｎａａ
高国平信雯郑雅楠高拓祁金玉张伟魏振宏
（阳农业大学，阳，１１１沈沈１０６）
摘
要
通过形态学和分子生物学方法鉴定沈阳地区刺槐心材腐朽病病原茵（编号为Ｐ）并在室内培养条１，
件下，用生长速率法研究了温度、Ｈ值、照、源和氮源对病原茵菌丝生长和茵落形态的影响。结果表明：采ｐ光碳病原茵Ｐ为槐生多年卧孔茵（ｅｎｉｏａｒｉｉｈｌ（ｒ）ｙ．；丝生长适宜温度为２２ ℃ ，宜ｐ值为５１ＰｒｎｒｂｎｐｉＭｕｒＲｖ）茵ｅｐｉｏｏａ．０— ５适Ｈ６光照对茵丝生长无显著影响。此外，１，Ｐ对碳源的利用以蔗糖为最佳，氮源以酵母膏最佳。关键词刺槐；原茵鉴定；病生物学特性；ＳｒＮＩＤＡＴ分类号￥９．６７２２
ｗｓｗｉｉｌａｇｆａｔｎｔｅｒｎｅｏｂｌ５～６．ｌｍｉａｉｎｈｄｎｂｉｕｆｃｎｍｙｅｉｍｏｈｈｅｍｙｅｉｍｅｅｔｏｄａＩｕｎｔａｏｏｖｏｓｅｅｔｏｃｌｌｏｕｇｗ．Ｔｃｌｒｔｕｇｗｂｓｎｍｅｉｒｗｔａｅｓｇｒａａｂｎｓｕｃｒｙａｔｘｒｃｓｎｔｏｅｅｏｒｅ．ｉｌｃｕａｓｃｒｏｏｒｅｏｅｔｔｉｇｎｒｓｕｃｓｌｎｓｅａａｒ

乐器共鸣板用木材的声学特性研究进展

乐器共鸣板用木材的声学特性研究进展刘镇波刘一星沈隽刘明（东北林业大学生物质材料科学与技术教育部重点实验室哈尔滨150040）摘要：木材的声学振动性能在很大程度上决定了乐器的质量；目前适合于制作乐器共鸣板的木材越来越少；在乐器共鸣板的实际生产中，都是以技师的主观评判方式进行选材，这已不适应当前的乐器工业发展的需要，因此越来越体现出乐器共鸣板用木材的声学振动特性研究的重要性。

文章论述了国内外乐器共鸣板用木材的声学振动特性研究发展、现状及发展趋势，以便为今后国内乐器共鸣板用木材的声学特性研究及乐器材的快速、客观评价体系的建立提供借鉴。

关键词：乐器共鸣板木材声学特性Advances in Study and Research on Acoustic Property of Wood for Soundboard of Musical InstrumentLIU Zhen-bo LIU Yi-xing SHEN Jun LIU Ming(Key Laboratory of Bio-based Material Science and Technology (Northeast Forestry University), Ministry of EducationHarbin 150040)Abstract: The musical instruments quality is determined by the acoustic vibration properties of wood in large degree. The timber, which is suitable for to manufacture the resonant board of musical instrument, is less and less at moment. In the production of resonant board, the technician selected the timber by subjective evaluation. Above all, the status doesn’t satisfy the development demand of musical instrument industry. So the research on wooden acoustic vibration properties is more and more important. In this paper, it discussed the development, present situation and prospect of wooden acoustic vibration properties of music instrument. Then it offered the reference to domestic research on acoustic vibration properties, auto and objective evaluation system of wood of musical instrument.Key words: Musical instrument, Soundboard, Wood, Acoustic property木材声学主要是研究木材在外在的声波源作用下所产生的振动特性、传声特性、空间声学性质（吸收、反射、透射）等与声波有关的木材材料特性。

欧美杨107杨制浆造纸性能的径向变异

ｃｅｃｌｏｋｎｒｃｓｓｉｌｍｅｔｄｆｒｐｌｉｇＵｎｌａｈｄｐｐｒｗｓｆｂｃｔｄａｄｉｃａｉａｒｐｒｉｓｈｍｉａ０ｉｇｐｏｅｓｗａｍｐｅｎｅｏｕｐｎ．ｃｂｅｃｅａｅａａｒａｅｎｔｍｅｈｎｃｐｏｅｔｉｓｌｅｗｒａｕｅｃｏｄｎｌ．Ｆｎｌｅｅｍｅｓｒｄａｃｒｉｇｙｉａｌｙ，ｖｒｔｎｐｔｒｆｕｐａｄｐｐｒｍａｉｇｐｏｅｉｓｗａｔｄｅａｅｎｔｅｄｔａａｉａｔｎｏｌｎａｅｋｎｒｐｒｅｓｓｕｉｄｂｓｄｏｈａａｉｏｅｐｔｃｌｅｔｄａｏｅｏｌｃｅｂｖ．Ｒｅｕｈｗｄｔａｈｖｒｇａｕｓｏｌｔｅｐｏｅｔｓｏｏｌｒｃｏｅ１７ｗｒｂａｎｄａｕｐｙｅｄｓｈｓｏｅｈｔｅａｅａｅｖｅｆｌｈｒｐｒｅｆｐｐａｌｎ０ｅｅｏｔｉｅｓｐｌｉｌｔｌａｉ４．９，ｋｐａｖｕ２１８３％ａｐａｅ２．６，ｔｎｉｎｅ５６・ｍ・ｇ，ｂｒｔｎｅ８３Ｐｌｅｓｌｉｄｘ８．１Ｎｅ一ｕｓｄｘ５．８ｋａ・ｍ・～．ａｄｔａｎｅ３．２ｉｇｎｅｒｉｄｘ１７
周亮高慧张利萍刘盛全
（徽农业大学，肥，３０６安合２０３）
摘要逐生长轮对１７杨木材进行硫酸盐法化学制浆，制备手抄纸片测定纸张力学性能，行制浆造纸０并进性能径向变异的研究。结果表明：０１７杨制浆造纸性能均值分别为制浆得率４．９，８３％卡伯值２．６抗张指数８．１２１，５６

MSEA

Author's personal copy
Materials Science and Engineering A 527 (2010) 3245–3252
Contents lists available at ScienceDirect
Materials Science and Engineering A
ห้องสมุดไป่ตู้
scanning electronic microscopy (SEM). The fracture behaviors of the basalt ﬁbers were analyzed from these fractographs. Based on the ﬁlament tows model and the statistical theory of ﬁber strength, a single Weibull statistical model was employed to describe the strength distribution of the basalt ﬁlament tows, and the Weibull parameters were obtained by the ﬁlament tows testing method. Consistency between the simulated and experimental results indicates that the model and the method are valid and reliable. 2. Experimental 2.1. Basalt ﬁbers The basalt ﬁlament tows (as shown in Fig. 1) were manufactured by Hengdian Group Shanghai Russia & Gold Basalt Fiber Co. Ltd. in China. The ﬁneness of the basalt ﬁlament tows is 2400tex/21800f (provided by the manufacturer). The diameter of monoﬁlamanet is 7 ␮m. The volume density is 2.6 g/cm3 . The photograph of the bobbin of basalt ﬁlament tows is show in Fig. 1. 2.2. Testing The quasi-static tensile tests (with the strain rate of 0.001 s−1 ) and high strain rate tensile tests (impact tensile tests) were performed on a MTS 810.23 materials tester system and a self-designed split Hopkinson tension bar (SHTB) apparatus (as shown in Fig. 2) [12], respectively. The basalt ﬁber tows were connected with the

材料科学与工程专业英语匡少平课后翻译答案精编WORD版

材料科学与工程专业英语匡少平课后翻译答案精编W O R D版IBM system office room 【A0816H-A0912AAAHH-GX8Q8-GNTHHJ8】Alloy合金applied force作用力amorphous materials不定形材料artificial materials人工材料biomaterials生物材料biological synthesis生物合成biocompatibility生物相容性brittle failure脆性破坏carbon nanotub e碳纳米管carboxylic acid羟酸critical stress临近应力dielectric constant介电常数clay minera l粘土矿物cross-sectional area横截面积critical shear stress临界剪切应力critical length临界长度curing agent固化剂dynamic or cyclic loading动态循环负载linear coefficient of themal expansio n性膨胀系数electromagnetic radiation电磁辐射electrodeposition电极沉积nonlocalizedelectrons游离电子electron beam lithography电子束光刻elasticity 弹性系数electrostation adsorption静电吸附elastic modulus弹性模量elastic deformation弹性形变elastomer弹性体engineering strain工程应变crystallization 结晶fiber-optic光纤维Ethylene oxide环氧乙烷fabrication process制造过程glass fiber玻璃纤维glass transition temperature 玻璃化转变温度heat capacity热熔Hearing aids助听器integrated circuit集成电路Interdisplinary交叉学科intimate contact密切接触inert substance惰性材料implant移植individual application个体应用deformation局部形变mechanical strength机械强度mechanical attrition机械磨损Mechanical properties力学性Materials processing材料加工质mechanical behavior力学行为magnetic permeability磁导率magnetic hybrid technique混合技术induction磁感应mass per unit of volume单位体积质量monomer identity单体种类molecular mass分子量microsphere encapsulation technique微球胶囊技术macroscopical宏观的naked eye 肉眼nonlocalized nanoengineered materials纳米材料nanostructured materials纳米结构材料nonferrous metal有色金属线nucleic acid核酸nanoscale纳米尺度Nanotechnology纳米技术nanobiotechnology纳米生物技术nanocontact printing纳米接触印刷optical property光学性质optoelectronic device光电设备oxidation degradation 氧化降解piezoelectric ceramics压电陶瓷Relative density相对密度stiffnesses刚度sensor传感材料semiconductors半导体specific gravity比重shear 剪切Surface tention表面张力self-organization自组装static loading静载荷stress area应力面积stress-strain curves应力应变曲线sphere radius球半径submicron technique亚微米技术substrate衬底supramolecalar超分子sol-gel method溶胶凝胶法thermal/electrical conductivity 热/点导率thermoplastic materials热塑性材料Thermosetting plastic热固性塑料thermal motion热运动toughness test韧性试验tension张力torsion扭曲Tensile Properties拉伸性能Two-dimentional nanostructure二维纳米结构Tissue engineering组织工程transplantation of organs器官移植the service life使用寿命the longitudinal direction纵向the initial length of the materials初始长度the acceleration gravity重力加速度the normal vertical axis垂直轴the surface to volume ratio 比表面密度the burgers vector伯格丝矢量the mechanics and dynamics of tissues 组织力学和动力学phase transformation temperature相转变温度plastic deformation塑性形变Pottery陶瓷persistence length余晖长度polymer synthesis聚合物合成Polar monomer记性单体polyelectrolyte高分子电解质pinning point钉扎点plasma etching 等离子腐蚀pharmacological acceptability药理接受性pyrolysis高温分解ultrasonic treatment超射波处理yield strength屈服强度vulcanization硫化1-1:直到最近，科学家才终于了解材料的结构要素与其特性之间的关系。

SimultaneouslySt...

increases recorded for the ultraﬁne nanoﬁbers smaller than250nm.The observed and comparisons with mechanical behavior of annealed nanoﬁbers allowed us to and toughness to low nanoﬁber crystallinity resulting from rapid solidiﬁcation ofsingle nanometers to micrometers by jetting polymer solutions in high electricﬁelds.3These nanoﬁbers the Methods section and Supporting Information. As-spun PAN nanofibers exhibited pronounced elasto-Figure1.Size eﬀects in mechanical properties and structure of as-spun PAN nanoﬁbers.(A)True strength;(B)modulus;(C)true strain to failure;(D)toughness(lines indicate comparison values for several high-performanceﬁbers and spider silk);(E)typical stress/strain behavior;(F)XRD patterns for nanoﬁber bundles with diﬀerent averageﬁber diameters and variation of degree of crystallinity with averageﬁber diameter(inset).parison of size eﬀects in as-spun and annealed PAN nanoﬁbers.(A)True strength;(B)modulus;(C)true strain to failure;(D)toughness.In allﬁgures,gray diamonds are for as-spunﬁbers and red squares for annealedﬁbers.(E)Typical stress/strain diagrams for annealedﬁbers on the same strain scale as in Figure1E;(F)XRD spectra for annealed nanoﬁber bundles with diﬀerent averageﬁber diameters.The annealed bundles were the same bundles studied in Figure1E.Nanoﬁber diameter distributions were not signiﬁcantly changed by the annealing.The inset shows the dependence of crystallinity on averageﬁber diameter for annealed nanoﬁbers.analyze the size effects in electrospun nanofibers,we plotted and studied correlations between various me-revealing that high strength is usually achieved at low toughness and vice versa(see shaded area inFigure3.Correlations of mechanical properties of nanoﬁbers of diﬀerent diameters.(AÀC)As-spunﬁbers:(A)true strength vs modulus;(B)true strength vs true strain to failure;(C)true strength vs toughness.(DÀF)Comparison between as-spun(blue diamonds)and annealed(red squares)nanoﬁbers:(D)true strength vs modulus;(E)true strength vs true strain to failure;(F)true strength vs toughness.Arrows in(F)point in the directions of decreasing nanoﬁber diameters.toughness values of spider pared to best annealed nanofibers had lowerbut higher strength;a property com-The best recorded properties of nano ceeded the properties of conventional PAN (250À400MPa strength and3À8GPaComparison of speciﬁc strength and speciﬁc energy to failure of as-spun PAN nanoﬁbers(diamonds) commercial and developmentalﬁbers and materials.2,5,26,30À32,34The arrow density indicates approximate diameters(see scale bar).The colored area represents the strength/toughness region occupied by traditionalSupporting Information forSimultaneously Strong and Tough Ultrafine Continuous Nanofibers Dimitry Papkov1, Yan Zou1, Mohammad Nahid Andalib1, Alexander Goponenko1, Stephen Z. D. Cheng2,Yuris A. Dzenis1*1Department of Mechanical and Materials Engineering, University of Nebraska-Lincoln, Lincoln, NE68588-05262College of Polymer Science and Polymer Engineering, University of Akron, Akron, Ohio 44325-3909 *Correspondence to: ***************Table S1: Reported size effects in individual electrospun polymer nanofibers.Polymer Diameterrange,nmProperty Change with Diameter Decrease Structure Modulus (E) Strength (σ)FailureStrain (ε)Toughness Orientation CrystallinityPLLA1270- 420 IncreasedslightlyNot studied Not studied Not studied Not studied Not studiedPCL2250-1300 Increasedsignificantlyfor diameters<500 nmIncreasedsignificantlyfordiameters<500 nmSize effectnotreported,but failurestraindecreasedwithincrease incrystallinityNotreportedIncreasedsignificantly withdiameterdecreaseIncreasedfrom 50-56% (XRD)with averagediameterdecreasePCL3350-2500 Increasedslightly,faster fordiameters<700 nm Increasedslightly,faster fordiameters<700 nmLimiteddata, butfailurestrainreported todecrease fordiameters<700 nmNotreportedIncreasedwithdiameterdecreaseIncreasedgraduallyfrom 42-50% (XRD)with averagediameterdecreaseNylon 6,64400-900 Increasedsignificantlyfor diameters<600 nm Not studied Not studied Not studied IncreasedgraduallywithaveragediameterdecreaseIncreasedgraduallyfrom 35-47% (XRD)with averagediameterdecreasePA 6(3)T5170-3500 Increased fordiameters<500 nmYieldstrengthincreasedfordiameters<1000 nmDecreasedsignificantly withdecrease indiameter(based onreportedstress-straindiagrams)NotreportedIncreasedsignificantly withaveragediameterdecrease<1000 nm(polarizedFTIR)AmorphousPCL & PCLEEP6200/300-5000Increaseddramaticallyfor diameters<700 nmIncreaseddramaticallyfordiameters<700 nmLargestrains tofailure;unaffectedby diameterNotreported*Not studied Nomeasurablechange inXRDcrystallinity(bundles)PAMPS755-250 Increasedsignificantly;Not studied Not studied Not studied Not studied Not studiedfaster fordiameters<70 nmPAN 8 200-700 Increased significantly, especially for longer spinning distance (increased crystallinity, orientation) Yield strength increased significantly Very large ultimate strain is reported todepend weakly on fiber diameter;stress-straindiagram for a 250 nmfiberexhibited150% strainNot reported / discussed* Increased significantl y with increase of spinning distance (decrease in average diameter) Low overallcrystallinity,increasedslightly with increase ofspinningdistance(decrease in average diameter)PAN 9 140-3000Increased dramatically for diameters <500 nm Increaseddramaticallyfordiameters<500 nm Not reported Not reported ND ND * Note: Although nanofiber toughness was not reported/discussed in these papers, it can be concluded from the evidence provided that toughness increased with the nanofiber diameter decrease, similar to the results discussed in this study.Data reduction from XRD experimentsFigure S1: A schematic illustrating XRD spectra analysis for as-spun (A)-(B) and annealed (C)-(D) nanofibers.XRD crystallinity was calculated by dividing the area under the crystalline peaks by the total area under the curve:%crystalinityൌܣ௖ଵ൅ܣ௖ଶܣ௔൅ܣ௖ଵ൅ܣ௖ଶ∗100The coherence length was calculated from the width of the main crystalline peak using the Scherrer equation:ܥ.ܮ.൫Å൯ൌܭߣߚܥ݋ݏΘൌ0.9∗1.542ඥሺܨܹܪܯሺܴܽ݀ሻଶെ0.002ଶሻܥ݋ݏΘwhere shape factor was taken as 0.9, the λ is the standard wavelength for a copper source, 0.002 was the instrumental peak widening calculated based on a single crystal Si standard, and θ is the Bragg angle for the crystalline peak.Correlation of Mechanical Properties of Nanofibers: Statistical AnalysisLinear regression curves for the true strength/modulus and true strength/toughness correlations were fitted separately for each of the nanofiber families (as spun and annealed). The associated Pearson correlation coefficients (R) and coefficients of determination (R2) are given in Table S2. Strong, positive correlations were observed, with the strongest correlation between strength and toughness of as-spun nanofibers.Nanofiber Family Modulus ToughnessR R2R R2As-spun 0.810.65 0.910.82Annealed 0.870.76 0.880.77Table S2: Pearson correlation coefficients and coefficients of determination for linear regression lines of true strength/modulus and true strength/toughness correlations.The slopes of the strength/modulus regression lines for the two nanofiber families (examined in SAS® Proc Glimmix software, Version 9.2 TS of the SAS System for Windows.Copyright ©2002-2008 SAS Institute Inc.SAS and all other SAS Institute Inc.product or service names are registered trademarks or trademarks of SAS Institute Inc., Cary, NC, USA.) were not statistically different at the α=0.05 confidence level (p-value for the slope/nanofiber family interaction term was 0.3345), while in case of strength/toughness correlations the lines for the two nanofiber families were statistically different at the same confidence level.Analysis of strength/failure strain relationships showed that the slopes of the regression lines for both samples were not statistically different from zero (p-values for strain and sample*strain terms were 0.67 and 0.24 respectively), indicating no correlation between these properties.Two parameter response surfaces for the correlation of strength with modulus and toughness were also plotted and analyzed. A second order linear regression model was examined. The model was subsequently reduced by eliminating statistically insignificant terms. While second order terms associated with modulus were eliminated from the model, the second order terms for toughness and linear by linear terms for modulus*toughness were retained. The coefficient of determination for the reduced models was 0.9 for both fiber families.The computed response surfaces for the two fiber families are shown in Figure S2. As can be seen, the increase in toughness for the annealed fibers accelerated relative to the increase in strength (see Figure S2B). This was also expressed by the negative coefficient of the quadratic term associated with toughness in the response surface for annealed fibers. For the as-spun fibers, the increase in toughness decelerated slightly relative to increase in strength (Figure S2A). However, the absolute value of the positive coefficient for the quadratic term in this case was more than one order of magnitude smaller, indicating weaker dependence.Figure S2:Fitted response surfaces for the true strength/modulus&toughness reduced second order linear regression model. A) As spun nanofibers; B) Annealed nanofibers.References(1) Tan, E. P. S.; Lim, C. T. Physical Properties of a Single Polymeric Nanofiber. Appl. Phys. Lett.2004, 84, 1603-1605.(2) Lim, C. T.; Tan, E. P. S.; Ng, S. Y. Effects of Crystalline Morphology on the Tensile Properties ofElectrospun Polymer Nanofibers. Appl. Phys. Lett. 2008, 92, 141908-141908-3.(3) Wong, S. C.; Baji, A.; Leng, S. Effect of Fiber Diameter on Tensile Properties of ElectrospunPoly(ɛ-caprolactone). Polymer 2008, 49, 4713-4722.(4) Arinstein, A.; Burman, M.; Gendelman, O.; Zussman, E. Effect of Supramolecular Structure onPolymer Nanofibre Elasticity. Nat. Nanotechnol. 2007, 2, 59-62.(5) Pai, C.; Boyce, M. C.; Rutledge, G. C. Mechanical Properties of Individual Electrospun PA 6(3)TFibers and their Variation with Fiber Diameter. Polymer 2011, 52, 2295-2301.(6) Chew, S., Y.; Hufnagel, T. C.; Lim, C., T.; Leong, K. W. Mechanical Properties of SingleElectrospun Drug-Encapsulated Nanofibres. Nanotechnology 2006, 17, 3880.(7) Shin, M. K.; Kim, S. I.; Kim, S. J.; Kim, S.; Lee, H.; Spinks, G. M. Size-Dependent Elastic Modulusof Single Electroactive Polymer Nanofibers. Appl. Phys. Lett. 2006, 89, 231929-3.(8) Naraghi, M.; Arshad, S. N.; Chasiotis, I. Molecular Orientation and Mechanical Property SizeEffects in Electrospun Polyacrylonitrile Nanofibers. Polymer 2011, 52, 1612-1618.(9) Papkov, D.; Zou, Y.; Dzenis, Y. In In Structure and Mechanical Properties of Continuous Polymerand Carbon Nanofibers; MRS Fall Technical Meeting; Boston, 2011.。

初植密度对大青杨木材显微构造特征及固碳量的影响

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初植密度对大青杨木材显微构造特征及固碳量的影响
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TENSILEPROPERTIESOFEARLYWOODANDLATEWOODFROMLOBLOLLYPINE(PINUSTAEDA)USINGDIGITALIMAGECORRELATION

GiYoungJeongGraduateResearchAssistantDepartmentofWoodScienceandForestProductsVirginiaPolytechnicInstituteandStateUniversityBrooksForestProductsCenter1650RambleRoadBlacksburg,VA24061-0503

AudreyZink-Sharp{ProfessorDepartmentofWoodScienceandForestProductsVirginiaPolytechnicInstituteandStateUniversity230CheathamHallBlacksburg,VA24061-0323

DanielP.Hindman*{AssistantProfessorDepartmentofWoodScienceandForestProductsVirginiaPolytechnicInstituteandStateUniversityBrooksForestProductsCenter1650RambleRoadBlacksburg,VA24061-0503

(ReceivedAugust2008)

Abstract.Thegoalofthisresearchwastomeasuretheelasticpropertiesandstrengthofearlywoodandlatewoodfromtwogrowth-ringpositionsofloblollypine.Becauseofthesmallspecimensize,acontact-lessstrainmeasurementwasappliedusingamicroscopewithanappropriatefieldofview.ThetensilepropertiesoftheearlywoodandlatewoodwerecalculatedfromloaddatafromaMinimattestercoupledwithelasticstraindatafromadigitalimagecorrelationtechnique.Incrementalloadingwasapplieduntilspecimenfailureoccurred.Elasticmodulus,Poissonratio,andstrengthgenerallyincreasedasthegrowth-ringnumbersincreased,exceptforthestrengthoflatewoodthatslightlydecreased.Elasticpropertiesandstrengthweresignificantlydifferentfordifferentgrowth-ringpositionsandintraringlayers.TheelasticmodulusforearlywoodandlatewoodwerebestfittedbyWeibulldistributionsregardlessofgrowth-ringpositions,whereasPoissonratioswerebestfittedbyWeibulldistributionsforearlywood1–10andlatewood11–20groups,andgammadistributionsforearlywood11–20andlatewood1–10groups.Straindistributionanalysisshowednonuniformstraindistributionsforthefourgroupsandalsoshowedmoreresistancetoloadforearlywoodandlatewoodfromahighergrowth-ringposition.

Keywords:Earlywood,latewood,digitalimagecorrelation(DIC),modulusofelasticity(MOE),ultimatetensilestrength(UTS),Poissonratio.

INTRODUCTIONAlargeportionofthewoodresourcesforstrand-basedcompositesaresuppliedfromplantation-growntrees.Thesetreesareharvestedona

short-termrotation,resultinginsmall-diameterlogsandahighproportionofjuvenilewood(Larsonetal2001).Thissituationhasplacedpressureontheindustrytousewoodresourcesmoreefficientlyforstrand-basedcompositepro-duction.Althoughthereismoreinterestintheefficientuseofwoodresources,thereislackof*Correspondingauthor:dhindman@vt.edu

{SWSTmember

WoodandFiberScience,41(1),2009,pp.51–63#2009bytheSocietyofWoodScienceandTechnologyknowledgeonthemechanicalbehaviorofearly-woodandlatewoodlayersofloblollypine(PinustaedaL.).Differentmorphologicalandchemicalvariationsofwoodcellsforearlywoodandlatewoodproducedifferentphysicalproper-ties.Comprehensiveknowledgeofcertainphy-sicalpropertiesofearlywoodandlatewood,includingcelllength,chemicalcomposition,mi-crofibrilangle,andspecificgravity,isavailablefrompreviouswork(TaylorandMoore1981;BendtsenandSenft1986;Larsonetal2001;Yehetal2006).

Indeed,itishardlysurprisingthatpreviousresearchershavemeasureddifferentmechanicalpropertiesbetweenearlywoodandlatewood.Thereislittleinformationabouttheeffectofthegrowth-ringnumbersonthemechanicalproper-tiesofearlywoodandlatewood.Frompithtobark,therearemanychangesinanatomicalstructure,includingsmallermicrofibrilanglesandlargercelldiameters(TaylorandMoore1981;BendtsenandSenft1986;Larsonetal2001).Thesechangesinearlywoodandlate-woodpropertiesmayleadtofundamentalchangesinwoodmaterials,whichcouldaffectwoodcompositeproduction.Therefore,mea-surementofearlywoodandlatewoodfromdif-ferentgrowth-ringpositionscanhelpmaximizeresourceuse.

However,elasticpropertiesaredifficulttomea-sureforearlywoodandlatewoodbandsasare-sultofthesmallspecimensizes.Becauseitisdifficulttouseanextensometerorstraingaugemountedtothesurfaceoftheearlywoodandlatewoodwithoutinterferenceofstrainmeasure-ment,noncontactmethodsarerequiredtomea-suretheelasticstraintocalculatetheelasticmodulus.Digitalimagecorrelation(DIC)isoneofthealternativeoptionsforthiscasebecausethistechniqueusesimagesofthesurfaceoftestspecimensacquiredduringtesting.AlthoughtheDICiswelldevelopedandwidelyusedtomea-surethestraindistributionofmaterialsqualita-tively,thereislackofresearchonmeasuringelasticstrainforwoodmaterialquantitatively.ToapplyDICtomeasuretheelasticstrain,acomplextestingsetupandmanycalibrationsare

neededtohaveaccurateresults.Inthisstudy,earlywoodandlatewoodpropertiesfromtwodifferentgrowth-ringpositionsweremeasuredusingDIC.Understandingearlywoodandlate-woodpropertiesfromdifferentgrowth-ringpositionswillpermitimprovedcharacterizationoftheconstitutivebehaviorofwoodstrandsandprovidemoredetailedcharacterizationofthemechanicalbehavior.