慈竹竹原纤维与黄麻纤维红外及二维相关光谱分析

以慈竹竹原纤维和黄麻纤维为对象,采用红外光谱法和二维相关红外光谱分析技术,对2种纤维及其化学处理后的单根纤维进行研究。结果表明:慈竹竹原纤维和黄麻纤维的一维红外光谱主要区别于1736cm-1处的CO伸缩振动和木质素苯环特征吸收峰;二者经双氧水-冰醋酸处理后,黄麻单根纤维在1736cm-1附近仍存在明显的吸收峰。在高分辨的二维同步相关谱中,慈竹竹原纤维和黄麻纤维特征差异更为明显,慈竹竹原纤维在1000～1250cm-1范围内有8个自动峰,1008cm-1处强度最大;黄麻纤维有7个自动峰,1217cm-1处强度最大;同时在1435～1750cm-1范围内,黄麻纤维在1726cm-1(C=O伸缩振动)处出现较强的自动峰,而慈竹竹原纤维光谱中没有。各区域内自动峰均为正相关。与化学处理前纤维谱图相比,二者单根纤维的二维相关红外光谱发生了改变,表明纤维成分对其热微扰过程中的变化有一定影响。初步研究表明:二维相关红外光谱为竹原纤维的识别提供了更为丰富的信息,可作为竹原纤维识别的一种新方法。     

竹材苯酚液化物及其甲醛树脂的FT-IR分析

采用傅立叶红外光谱和核磁共振法分析了竹粉在苯酚溶剂作用下酸催化液化产物的化学结构,以及液化物-甲醛树脂胶黏剂的结构特征.分析表明:竹材苯酚液化物的FT-IR图谱在1595.32～1512.70 cm-1处C=O伸缩振动、C=C伸缩振动、芳环骨架振动增强,在 1360.77 cm-1 处面内O-H弯曲振动、1028.62 cm-1 伯醇C-O伸缩振动及手纹区有强吸收峰;1512.70 cm-1处酚类C-O吸收及832.79～691.68 cm-1 处吸收带增强.竹材苯酚液化物-甲醛树脂和普通酚醛树脂的FT-IR图谱非常类似.     

醋酸水溶液预处理对柳杉木材炭化的影响

杉木(日本柳杉)经醋酸水溶液处理后，重量减少。将处理前后柳杉木材在4℃下进行炭化，得到了木醋液、木焦油和木炭。与未处理材相比，处理材木醋液的收率增加，而木焦油和木炭的收率减少。处理液的醋酸浓度增加后，木醋液和木焦油的收率几乎不变，但木炭的收率稍微减少了。用毛细管气相色谱法对木醋液的成分进行了定量分析。与未处理材相比，处理材木醋液中糠醛(呋喃甲醛)及5-羟甲基糠醛的收量增加，而羧酸类、苯酚类、邻苯二酚、愈创木酚类及麦芽酚的收量几乎不变。当醋酸浓度从0增至3％时，糠醛的收量随着增加，但是当醋酸浓度从3％增至30％时，其收量却几乎不变。     

杉木间伐材高温热处理后化学成分的变化

以空气和菜子油为介质,分别用180,200和220℃处理杉木间伐材2和4 h,测定处理样综纤维素、纤维素、Klason木质素和苯醇抽出物相对含量的变化,并用傅里叶变换红外光谱分析高温热处理过程中木材内综纤维素的变化规律.结果表明:热处理后试材综纤维素含量均有不同程度的降低、纤维素总体降低较少,相应的苯醇抽出物含量、Klason木质素含量增加;温度升高、处理时间延长,木材主要化学组成的变化程度增大;在隔氧的油介质中进行热处理,试件的化学成分变化程度低于空气介质中热处理材;方差分析表明不同温度、时间、介质对主要化学组成产生极显著的影响;FTIR分析表明,180℃热处理时开始发生半纤维素分解,到200℃时纤维素也开始分解;氧气氛围对糖残基的热分解具有促进作用.在3 412,1 050,898 cm~(-1)附近相关糖残基,1 736 cm~(-1)附近相关C=O以及2 907 cm~(-1)附近对应C-H的吸收强度的变化也表征出热处理过程中各化学成分的变化规律.     

木聚糖酶处理对麦草化学组成及其纸浆纤维长度的影响

研究了木聚糖酶预处理对麦草的化学组成及其化学浆纤维长度的影响。结果表明,木聚糖酶酶处理后原料的热水抽出物和1%NaOH抽出物含量增加,乙醇-苯酚(苯-醇)抽出物含量有所降低,酶处理对原料中酸不溶木质素含量影响很小,但聚戊糖含量降低。延长酶处理时间,对酶处理最终结果影响不大。酶处理后的稀碱抽提可以有效地降低原料中的木质素和聚戊糖含量。与对照样品相比,酶处理后麦草化学浆的纤维长度有所增加。上述结果从理论上解释了酶法制浆过程中出现的一些现象。     

松材线虫罹病木化学成分分析

通过对南京地区黑松、马尾松健康株和松材线虫罹病株的综纤维素、酸不溶木质素、苯醇抽出物、乙醚抽出物、1%NaOH抽出物等含量的测定,罹病木的纤维素、半纤维素和木质素几乎不被破坏,而苯醇和乙醚抽出物含量明显下降。因此,处理后的罹病木可以用作造纸、纤维板和刨花板的原料。     

东北常见树种木材形成早期组织波谱特征差异分析

【目的】研究东北主要商品材树种木材形成早期组织的化学特征及其在树种间的差异,为揭示树木生长过程中木材细胞壁的自组装行为和木材形成的分子机制提供科学依据。【方法】选取东北10种重要商品材树种,采集木材形成早期组织,利用红外光谱和X射线衍射技术分析木材形成早期组织的波谱特征。【结果】红外光谱差别主要在波数900～2 000 cm~(-1)之间的指纹区域。针叶树种木材中波数1 735 cm~(-1)附近由木聚糖乙酰基C O伸缩振动引起的吸收峰相对强度显著小于阔叶树种木材。针叶树种木材中1511cm~(-1)处表征苯环碳骨架振动的吸收峰较明显,尤其是云杉和落叶松。针、阔叶树种木材在波数1 630～1 660 cm~(-1)之间均出现不同强度的吸收峰,峰形较宽,该峰归属为蛋白质肽段中氨基化合物振动引起。红外光谱二阶导数处理后,针叶树种木材在波数1 266 cm~(-1)处有明显吸收峰,阔叶树种木材中并未发现,该峰归属为愈创木基环加CO伸缩振动。而阔叶树种木材在1245cm~(-1)处有较明显吸收峰,该峰由木质素紫丁香基环振动引起。多数树种木材X射线衍射图谱I002有较强的衍射峰,但Iam的衍射峰并不明显,尤其是阔叶树种木材。因此推测木材形成早期组织中纤维素的晶型、晶胞或晶区大小与成熟木材不同。【结论】针、阔叶树种木材形成早期组织中木质素和半纤维素的沉积过程有所差别,这有助于揭示木材形成过程中化学成分和结构的变化规律。     

蒸煮爆破处理过程中毛竹材加工剩余物主要化学成分的变化研究

采用硫酸水解法(aldito-acetate procedure)、X射线粉末衍射(XRD)、傅里叶变换红外光谱(FTIR)分析了蒸爆过程中毛竹材加工剩余物纤维聚集态结构及主要化学成分的变化.研究结果表明,(1)毛竹材加工剩余物经蒸爆处理,60%左右的半纤维素水解,木质素低分子化且裸露到纤维表面,易被80%乙醇及木质素溶剂提取,从而实现毛竹材加工剩余物主要组分的有效分离.(2)毛竹材加工剩余物经蒸爆处理,80%乙醇抽提物得率提高,综纤维素得率减少,木质素含量减少:葡萄糖相对含量增加,半纤维素降解明显.(3)210℃处理10 min和220℃处理10 min的蒸爆浆的化学组成变化几乎没有区别,但两者与200℃处理10 min差别较大,210℃处理10 min是毛竹材加工剩余物适宜的处理温度.(4)FTIR结果显示蒸爆处理后在1040～1060 cm-1区的吸收峰分裂为明显的2个峰表明半纤维素降解,1166 cm-1处的吸收强度明显减弱,表明C-O-C键有不同程度的断裂.X-身寸线衍射分析结果显示毛竹材加工剩余物蒸爆处理后纤维素相对结晶度增加.     

高温热处理落叶松木材尺寸稳定性及结晶度分析表征

对以热处理介质为空气和N2下落叶松木材(热处理温度180～240 ℃,热处理时问4 h)的抗胀缩率(ASE)、结晶度及红外光谱进行测定和表征.结果表明:相同热处理时间下,随着热处理温度的升高,在180～220℃范围内,无论热处理介质是空气或N2时,落叶松木材的ASE值均达60%以上,介质为N2的木材的ASE值低于空气的;红外吸收光谱表明,3 380 cm-1附近-OH基团的伸缩振动强度随着热处理温度的升高而减少且变化显著,1 730 cm-1附近羰基随温度的升高吸收强度降低,相同条件下N2保护下羟基和羰基吸收峰强度高于空气的;落叶松木材在热处理时间相同的情况下,经过不同超高温度的处理后,木材结晶度的变化趋势是先增加、后减小、再增加,结晶度可达65%以上,同等条件下,N2氛围下木材的结晶度高于空气的.     

脱木质素处理对木材组分和物化性能的影响研究北大核心

脱木质素是提高木材性能、制备新型木基功能材料的重要方法之一。采用由亚氯酸钠、冰醋酸和蒸馏水混合而成的改性剂对木材进行脱木素处理,研究脱木质素对木材材性的影响,并以残留木质素含量为指标,经单因素和正交试验获取最优工艺。结果表明:当亚氯酸钠溶液浓度为4 wt%、处理温度为100℃、处理时间为6 h、处理液浴比为1∶30时,残留木质素的含量均值为0.081 g。经过脱木质素处理后的木材,其材色变亮,质量损失率增加,吸水率明显提高。其中,明度值L*从52增加到85,质量损失率增至26%,吸水率从1.39%增至3.44%。研究结论可为脱木质素木材材性的综合评价及其加工利用提供理论依据。     

Treatment of sugi （Cryptomeria japonica D.） sapwood with aqueous solution of acetic acid

Sugi sapwood samples were processed with aqueous solution of acetic acid in order to find the response of the weight of sugi sapwood and the treatment of aqueous solution of acetic acid. The result showed that loss of weight for the treated sugisapwood was about equal to yield of extracts from sugi sapwood, and increased with the increment of the concentration of aqueous solution of acetic acid. Fourier transform infrared spectroscopy spectra changes of the treated sugi wood and extracts from sugi sapwood were analyzed by FT-IR spectroscopic technique. Increasing tendency of absorption intensities of the stretching vibration at 3 400 cm^-1 of hydroxyl group (OH) and C=C in lignin stretching vibration at 1510 cm^-1 of benzene ring inlignin were observed from FT-IR of the treated sugi sapwood. From FT-IR spectra of extracts from sugi sapwood by aqueoussolution of acetic acid, the dissolution of lignin was observed during the treatment with 30% acetic acid solution aqueous.     

Chemical changes in terpenes of sugi (<Emphasis Type="Italic">Cryptomeria japonica</Emphasis>) wood during steam drying in kiln at high temperature

Sawdusts of sugi (Cryptomeria japonica) wood prepared before and after steam drying at 120°C in a kiln were extracted with n-hexane and ethyl acetate to give n-hexane extracts and ethyl acetate extracts. From gas chromatography-mass spectrometry analysis of the ethyl acetate extracts from woods before and after steam drying, the components of 4-epi-cubebol, cubebol, and 2,7(14),10-bis-abolatrien-1-ol-4-one, which existed in the raw sugi wood, were proved to disappear in the steam-dried wood. These components were also absent in the ethyl acetate extract of the steam-condensed solution of waste steam from the kiln outlet. When these three components were treated with 0.2% (v/v) acetic acid solution at 120°C, δ-cadinene was produced as a major product from both 4-epi-cubebol and cubebol by dehydration and cleavage of the cyclopropane ring, and cryptomerone from 2,7(14),10-bisabolatrien-1-ol-4-one by hydration. The chemical changes of the three components presumably occur during steam drying of the sugi wood. This study was presented in part at the 85th Spring Meeting of the Chemical Society of Japan, Kanagawa, Japan, March 26–29, 2005     

Evaluation of the self-bonding ability of sugi and application of sugi powder as a binder for plywood

Binderless particleboards were manufactured from sugi (Cryptomeria japonica D. Don) heartwood and sapwood by hot-pressing (pressure: 5 MPa; temperatures: 180°, 200°, and 220°C; times: 10, 20, and 30 min), and the board properties [internal bonding (IB), thickness swelling (TS), water absorption (WA)] were investigated to evaluate the self-bonding ability. The IB, TS, and WA of the boards from sugi heartwood were better than those of the boards from sugi sapwood at any hot-pressing condition. Therefore, it was suggested that the self-bonding ability of sugi heartwood was superior to that of sugi sapwood. Then, sugi heartwood and sapwood powder with grain size 10 βm were used as a binder for plywoods. Four kinds of plywood were manufactured from the combination of powder and veneer, both of which were prepared from sugi heartwood and sapwood under the same hot-pressing conditions as the binderless particleboard, and the adhesive shear strength and wood failure of the plywood were investigated. As a result, the plywood composed of sugi heartwood veneer met the second grade of JAS for plywood, when either powder was used as a binder, when they were pressed at 200°C for 20–30 min and 220°C for 10 min.     

Distribution of boron in wood treated with aqueous and methanolic boric acid solutions

The distributions of boron in Japanese cedar (Cryptomeria japonica D. Don) sapwood blocks treated with aqueous or methanolic boric acid [B(OH)₃] solutions were explored through Raman spectroscopy and prompt gamma-ray analysis (PGA). B(OH)₃ was the sole boron species observed in Raman spectra of the wood blocks treated with either solution. Plots of weight gain of the treated wood blocks versus boron concentration in treatment solutions were found to be linear. The results indicated that the methanolic solution makes it possible to impregnate wood with much larger amounts of boron than the aqueous solution. PGA confirmed that B(OH)₃ was highly enriched near the end grains of the treated wood blocks. Raman measurements suggested that boron content in the bulk of the wood block is not as large as expected from the weight gain of the treated wood blocks when an ordinary air-drying method is used. It was concluded that the aqueous solution impregnates the cell walls of wood with boron more easily than the methanolic solution. Part of this report was presented at the 55th (Kyoto, March 2005) and 56th (Akita, August 2006) Annual Meetings of the Japan Wood Research Society. This article follows the previous rapid communication “Analysis of boron in wood treated with boric acid solutions using Doppler broadening method of prompt gamma-rays.” J Wood Sci (2006) 52:279–281     

二乙醇胺基木质素非离子表面活性剂的制备及表征

依据酸沉淀法对碱木质素进行了分级,分级后pH值4 ～ 6的木质素与环氧氯丙烷、二乙醇胺反应,制备了木质素基非离子表面活性剂.通过红外光谱、含氮量的测定对产物的结构进行了表征,通过表面张力测定对产品的表面活性进行了分析.结果表明:木质素基非离子表面活性剂固含量为32.6%,含氮量为1.99%,红外光谱分析可确定在木质素上引入了环氧氯丙烷和二乙醇胺,水溶液表面张力降低到53.27mN/m,表明二乙醇胺基木质素非离子表面活性剂(DLNS)具有良好的表面活性.另外通过与十二烷基磺酸钠(SDS)复配后浊度的测定,表明产品在SDS与DLNS的体积比为20: 3 ～ 20: 20范围与SDS复配,浊度较低,复配效果较好.     

“I-214杨”心材、边材木质素的红外光谱、质子和碳-13核磁共振波谱特征研究

对从杨树心、边材提取的磨木木质素进行了元素分析和红外光谱（FTIR）质子和碳－13核磁共振波谱（^1H,^13C NMR)等化学特征研究。研究结果表明：杨树心、边材木质素的经验式分别为C9H7．16O2．38（OCH3）1．99和C9H8．61O2．73（OCH3）1．33。心材木质素甲氧基含量28．16％,比边材高8．73％。两种木质素均具有典型阔叶材的特征,化学结构类型基本一致,碳骨架结构基本相同,但化学官能团和键型的组成上存在差异。     

Chemical characterization of Pinus halepensis sapwood and heartwood

ABSTRACT

This paper describes the chemical composition of sapwood (SW) and heartwood (HW) of Pinus halepensis Mill stem. Extractives were first isolated by accelerated solvent extraction and then analysed by gas chromatography-mass spectrometry (GC-MS). The cellulosic polysaccharide content present in the pre-extracted wood samples was determined with acid hydrolysis and GC. The hemicelluloses content was determined with acid methanolysis and GC. Free monomers were additionally analysed by GC. The amount of lignin was determined gravimetrically by the Klason lignin method and the acid-soluble lignin was determined by a UV method. Formic and acetic acids in wood were determined after alkaline hydrolysis and analysed by HP-SEC. It was found that lipophilic and hydrophilic extractives were more abundant in heartwood (1.6% and 2.5%) than in sapwood (1.1% and 1.8%). Celluloses content was higher in sapwood (42.5%) than in heartwood (39.7%), whereas lignin, hemicelluloses and sugar monomer contents were more abundant in heartwood (28.9%, 26.8% and 0.3%) than in sapwood (28.0%, 24.5% and 0.2%). The variation in acetic and formic acids and ash contents between sapwood (0.7%, 0.2% and 0.5%) and heartwood (0.6%, 0.1% and 0.4%) was small. The acetylation degrees were found to be slightly similar in sapwood (0.4) and heartwood (0.3).     

Improvement of penetrability of sugi wood by impregnation of bacteria using sap-flow method

The sap flow method of wood impregnation was conducted to aid the movement of bacteria through the living tree, thereby accelerating their distribution through wood within a short time. When log-pond water containing mixed species of bacteria were introduced in the living trees by butt-end dipping and then laid horizontally for 6 months, bacteria could be delivered by sap flow vertically through the sapwood tracheids up to the high portions from the butt-end of trees; they could be detected in the ray parenchymal cells. The sap-flow method was assumed to deliver the bacteria to sapwood and heartwood at high levels of standing sugi (Cryptomeria japonica D. Don) trees. Degradation of the pit membranes was observed even at more than 3 m upward from the butt-end after the treatment in sapwood, as well as around the butt-end of the trees. The uptake of the aqueous dye solutions in sapwood of the treated logs were about eight times more than those of control specimens after 8h.Part of this report was presented at the 40^th annual meeting of the Japan Wood Research Society, Tsukuba, April 1990; the 41^st annual meeting of Japan Wood Research Society, Matsue, April 1991; and the IUFRO 4^th international conference on wood drying, Rotorua, New Zealand, August 1994     

Preparation of amphiphilic lignin derivative as a cellulase stabilizer

A polymeric amphiphile, PE-AL, was prepared from acetic acid lignin (AL) obtained by acetic acid pulping of birch under atmospheric pressure with polyethylene glycol diglycidyl ether (PE) as the crosslinker. The behavior of PE-AL solutions and the complex formation of PE-AL with protein were investigated to clarify the function of this novel lignin derivative. The reduced viscosity of the amphiphile in aqueous solution was low (<0.3dl/g), and it decreased with increasing concentration in dilute solution. This suggested that the PE-AL in aqueous solution has a structure similar to that of Einstein's sphere and shrinks upon hydrophobic interaction among the structural moieties in AL and the exclusive volume effect. The amphiphilic PE-AL obviously formed a complex with bovine serum albumin (BSA) at 4°C with a reaction time of about 1 week. After complex formation with cellulase for 1 week, the cellulase activity of the resulting complex is significantly enhanced and is preserved after recycling the complex for hydrolysis of cellulosic materials several times.Part of this work was presented at the 48th Annual Meeting of the Japan Wood Research Society, Shizuoka, April 1998