Flakeboards Made From Aspen and Southern Pine Wood Flakes Reacted with Gaseous Ketene

Abstract

Southern pine and aspen wood flakes were chemically modified by reaction at ca. 55°C with ketene in the absence of solvent. Reactions were relatively slow, with weight gains of up to 17% and 20%, respectively, obtained. Acetyl content correlated with weight gain only up to the 12% level. Water and solvent extraction of ketene-modified southern pine and aspen flakes showed very little loss in acetyl.

Flakeboards made from southern pine and aspen flakes treated with ketene showed a greatly reduced rate and extent of swelling resulting from liquid water sorption as compared to control boards. Similar results were obtained in swelling tests done in water vapor. Ketene modification had a much greater effect on improving dimensional stability properties of aspen flakeboards than on southern pine flakeboards.     

高性能水性复配型光稳定剂应用于南方松表面处理

木质素受到阳光照射下很容易劣化,要保留天然木器纹路和颜色的外观,目前工业界常用的方式是在木器的表面涂上一层添加有紫外线吸收剂(UVA)和受阻胺光稳定剂(HALS)的保护清漆。但是这种涂布方式的保护效果比较有限,实验结果显示,在涂布清漆之前,先将木器的表面进行防止老化处理,可以更有效地延长保护时间。文章针对水性透明清漆开发了一种复配型光稳定剂Eversorr AQ1,在南方松的材质表面进行一层处理。人工加速老化试验结果显示,增加Eversorb AQ1在透明清漆里面的有效浓度,可以增强相对保护效果,但是如果在涂布清漆之前先在南方松的表面用光稳定剂W1处理,其耐候性可以比未处理过的增加50%。虽然实验数据显示增加清漆涂层膜厚也可以得到某种程度的保护效果,但是与增加Eversorb AQ1的有效浓度,或者先将木器的表面进行处理,增加清漆的涂膜厚度并不是一种最佳的选择。     

Vapor Phase Acetylation of Southern Pine,Douglas-Fir,and Aspen Wood Flakes

Abstract

Southern pine, Douglas-fir, and aspen wood flakes were acetylated with acetic anhydride vapor and compared with flakes acetylated with liquid acetic anhydride diluted with xylene. The rate of acetylation was much lower for the vapor than for the liquid phase reaction. Acetylation weight percent gains above 20 were achieved by both methods. Flakeboards made from both types of flakes absorbed much less water, both in water soaking tests and when subjected to humid air, and swelled at a lower rate and to a lower extent than did control boards. At low weight gains of vapor phase acetylation, the rate and extent of swelling were higher than those found for the controls.

Hygroscopicity of the resulting flakeboards decreased with increased level of wood acetylation. The equilibrium moisture content for flakeboards made from liquid phase acetylated flakes was the lowest at each relative humidity tested as compared to control boards, and boards made from vapor acetylated flakes at the same weight gain.     

Spectroscopic Analysis of Southern Pine Treated with Chromater Copper Arsenate. I. X-Ray Photoelectron Spectroscopy (XPS)-17

Abstract

The amount of southern pine lumber treated with chromated copper arsenate annually is considerable, yet the association of this preservative with the wood structure is not clear. The current study was undertaken to elucidate the nature of chemical reactions occurring between the components of the treating solution and the constituents of wood. Small, clear Southern pine samples were treated with six different preservative solutions (Cr; Cr/Cu; Cr/As; CCA-A; CCA-B; CCA-C), at 6.4 and 40 Kg/m³ (0.4 and 2.5 pcf) retentions, and compared to water treated and untreated controls. Samples were dried following treatment and analyzed by X-ray photoelectron spectroscopy (XPS). Evaluation of XPS data indicated that the preservative components reacted with wood, through aromatic and possibly alkene substitution, while oxidation of hydroxyl groups was not detected. The proposed wood/CCA bonding also offers an explanation for differences in hardwood and softwood durability following treatment.     

Formation of 7-Ketodehydroabietic Acid at the Radiata Pine Wood Surface. and its Effect on Wood Yellowing

Dehydroabietic acid (1), an extractive of radiata pine wood has been shown to undergo light-catalysed oxidation at the wood surface to 7-ketodehydroabietic acid (3), identified by mass spectrometry as the methyl ester (4). and compared with authentic compound. 7-Ketodehydroabietic acid (3) was not generally further oxidised, except in two samples examined which contained a trace amount of 7-ketoabieta-6.8,ll,13-tetraen-18-oic acid (7). Consequently, 7-ketodehydroabietic acid (3) accumulated as a major oxidised resin acid product at the radiata pine wood surface when the surface was exposed to air and light. After one year, the compound (3) comprised approximately half of the extractable aromatic ring-C resin acids. Application of synthetic 7-ketodehydroabietic acid (3) to exhaustively methyiene chloride extracted radiata pine wood blocks, and exposure of treated and untreated blocks to sunlight did not result in alteration of the yellowing rate of the wood surface.     

测定柠檬黄的电位型漆酚树脂化学传感器研究

:报导了以湖北长阳县出产的山漆为原料合成漆酚树脂 ,以此漆酚树脂为载体 ,研制了测定合成食用色素柠檬黄的电位型化学传感器。此传感器对柠檬黄浓度在8.0× 1 0 -7～ 1 .0× 1 0 -3 mol/L间的响应符合 Nernst关系式 ,斜率为 2 1 .0 m V( 30°C,p H6.0 ) ,检测下限为 3.0× 1 0 -7mol/L。传感器的选择性、重现性和稳定性良好 ,对样品的测定结果与食用色素通用测试方法 ( OT- 1 5)基本一致。     

Impregnation and polymerization of vinylic monomers in porous media. I. Kinetics of impregnation

In this work, we have studied the mechanism and kinetics of penetration of monomers and of liquids of low molecular weight into porous media such as asbestos cements. Although the phenomenon is physically different from a molecular diffusion, the kinetics of impregnation are well represented by Fick's laws of diffusion. We observe an excellent agreement between the experiment and the theoretical equation as long as the degree of impregnation does not exceed 80%. If, in order to represent this, we use a simplified model introducing a flow governed by Poiseuille's law through a bundle of capillaries of the same diameter, we obtain a parabolic law which is verified up to only 55%. We have demonstrated the physicochemical parameters which influence the kinetics of impregnation. The results can be summarized by the following empirical equation: Where η represents the viscosity of the liquid, γ the surface tension, θ the angle of contact, γ the average radius, and ? the porosity; D^* appears as a constant equal to 2.0 × 10⁹ cm^?2. The standard deviation of its determination is 0.14 × 10⁹ cm^?2.     

Evaluation of Kraft-PS Cooking for Eucalypt and Pine Wood Chip Mixtures

The purpose of this study was evaluating polysulfides (PS) as additives in kraft cooking of wood mixtures eucalypt (E) and pine chips (P) wood mixtures, namely: 50E/50P, 70E/30P, and 90E/10P. Bleaching (O(D/A)(EP)D) and refining of pulps were also investigated. The PS addition (1.5 or 3.0%) to the kraft cooking preserved the hemicelluloses resulting increased pulp yield and reduced H-factor. The oxygen delignification was more efficient for chip mixtures containing higher proportion of pine chips, but was not largely affected by the addition of PS. The bleach chemical consumption was not significantly influenced by PS dosage or by the wood chip mixture. The burst and tear indexes were improved by increasing the proportion of pine chips to the mixture, but an opposite effect was observed for refinability, tensile index, and opacity. The kraft-PS pulps showed increased refinability, tensile, and burst strengths in relation the standard pulps, but lower opacities.     

改性蜜胺树脂香精微胶囊的制备研究

为解决日化香精易挥发变质的问题,拓宽其应用领域,采用原位聚合法制备了一系列蜜胺树脂（MF）香精微胶囊。以低甲醚化蜜胺（L-MMF）树脂为例,傅立叶变换红外光谱（FT-IR）的结果证实了微胶囊对香精的良好包覆性,热失重〈TGDTG）分析说明微胶囊大幅提高了香精的耐热性能。进一步采用脲、间苯二酚、聚乙烯醇（PVA）、聚乙二醇（PEG）、氯化钠对蜜胺树脂进行改性并与未改性的树脂及不同甲醚化程度的蜜胺树脂进行对比,研究了改性对微胶囊包覆效果的影响。结果表明,低甲醚化蜜胺树脂和聚乙烯醇改性蜜胺树脂对香精的包覆效果较好,所得香精微胶囊粒径小,分布窄,包覆率高。     

Comparing the Variation of Needle and Wood Terpenoids in Scots Pine Provenances

We determined variation in both the concentration and composition of terpenoids in needles and wood within nine Scots pine (Pinus sylvestris) provenances. Seedlings of different provenances representing a 1200-km N–S transect from Estonia to northern Finland were cultivated in Suonenjoki nursery field, central Finland, for seven years. Growth of seedlings and the number of vertical resin ducts in wood were also determined. -Pinene and 3-carene were the major monoterpenes both in the needles and wood. The total monoterpene concentration was about five times higher in the needles than in the wood. A strong positive correlation was found between proportional quantities of several terpenes of the needles and wood, particularly for 3-carene, sabinene, and terpinolene. The needles contained both labdane-type and tricyclic resin acids, whereas the wood contained only tricyclic ones. The wood had a four times higher tricyclic resin acid concentration than the needles. The highest total monoterpene concentration in the needles and in the wood occurred in the most northern Muonio provenance and in the most southern Saaremaa provenance plants, respectively. The amount of high 3-carene genotype trees decreased among the northern provenances. The wood of the most northern Muonio provenance showed the lowest total resin acid concentration, but provenance did not affect total tricyclic resin acids in the needles. Korpilahti provenance trees from central Finland had the best growth in height. In addition, Korpilahti and Ruokolahti provenance trees showed largest radial growth of stem and smallest number of vertical resin ducts. The results suggest that especially the proportional quantity of 3-carene in the needles could be used in estimating the amount of this compound in the wood and vice versa.     

Improvement of Modified Wood Properties with Addition of Chestnut Tannins in Lactic Acid-Based Treatments

Wood modification treatments based on lactic acid oligomers (OLA) and monomers (LA) enhance beech dimensional stability (up to 70%) and biological resistance (less than 3% weight loss according to EN113). Chestnut wood tannins natural biological activity might improve the modified wood durability with milder curing conditions. Treatment consisted of the impregnation of monomers or oligomers mixtures followed by curing (140?°C/160?°C for 48h). Tannins addition is almost inconsequential with oligomeric-based treatment but improved the monomeric-based treatment. In this case, modified wood biological resistance and product persistence were increased. OLA impregnated wood cured at 160?°C was always the best performing treatment regarding dimensional stability and durability, but the addition of tannins in LA systems conferred promising properties to wood allowing simplification of the modification process.     

Identification of Effective Diffusivities in Anisotropic Material of Pine Wood during Drying with Superheated Steam

Simulation of 3D drying of anisotropic solids requires knowledge of the diffusivities of moisture in all three directions. These are seldom available in the range of temperatures and moisture contents of interest. This article presents methodology for identification of axial and radial diffusivities in wood in superheated steam drying and the results for wood of Pinus silvestris at a steam temperature 160°C and atmospheric pressure. Axial diffusivity (along fibers) was 5.76 times higher than radial diffusivity.     

高含固率C.I.分散黄211分散体

在N-乙基-2-羟基-3-氰基-4-甲基吡啶酮中预先加入分散剂再与对氯邻硝基苯胺的重氮盐进行偶合反应,可以得到高含固量的反应液,其中染料的含量高于10％,比传统方法制得的染料含量高出一倍,可节水1/2.用上述方法制造的染料粒径主要在6～10 μm范围,研磨比较容易,按同样的方法研磨比传统的方法研磨时间要缩短1/2.研磨时加入分散剂(自制的高效分散剂),含量为染料干品的30％ ～ 40％,此举可使染色残液中分散剂的含量减少2/3.研磨后形成的分散体储存稳定性好,放置三个月尚未分层.染色的结果表明,使用该分散剂制得的C.I.分散黄211与标样相比强度和色光一致,但鲜艳度要高,因为分散剂中含有可螯合钙、镁等金属离子的基团.     

The Polymorphism of C.I. Pigment Yellow 5

Department of Physics Brunei University Uxbridge Middlesex UB8 3PH By interpretation of X-ray diffraction patterns it has been found that C. I. Pigment Yellow 5 (α-[1-hydroxy-ethylidene\acetanilide-α-azo-\2′;-nitrobenzene]) is dimorphic, both forms being available commercially. The single-crystal data and X-ray powder pattern are reported for one form (termed α) and the powder pattern has been indexed from the single-crystal unit cell dimensions. The second form (β) has only been obtained as a powder, and the powder pattern is reported. This form changes to the α-form by recrystallisation from toluene.     

预分散C. I. 颜料黄14的制备研究

以3,3'-二氯联苯胺盐酸盐(DCB)和邻甲基乙酰乙酰苯胺(AAOT)为原料,在偶合反应结束后,向制备的C.I.颜料黄14(PY14)水分散液中添加聚乙烯蜡(PEW),考察了PEW添加量、加热温度、加热时间、搅拌转速、pH、PEW粒径对颜料性能的影响。得到较优制备条件为PY14与PEW质量比1.0∶1.0、加热温度80℃、加热时间20 min、40～60目PEW、pH=7.0、转速250 r/min,在该条件下制备出直径为1～2 mm、粒径均一、具有核壳结构和疏水性能的预分散C.I.颜料黄14(预分散颜料PY14)。预分散颜料易于从水相分离,滤饼含水量从PY14颜料的79.29%降低至预分散颜料PY14的59.85%,过滤时间为PY14颜料的1/20;分散过滤值(FPV)从PY14颜料的0.75 MPa/g降低至预分散颜料PY14的0.06 MPa/g;所得颜料不需经过强力粉碎,可抑制粉尘污染的产生;在保持与原颜料相近的色光、饱和度、鲜艳度等颜料性能前提下,提升了颜料的着色力。     

C.I.活性黄145的生物降解特性研究

文章主要研究在厌氧、好氧、厌氧/好氧条件下,通过采用活性污泥法生物降解活性染料C.I.活性黄145,从而了解该染料生物降解的特性。研究结果表明,在无外加碳源,染料浓度100 mg/L条件下,厌氧、好氧、厌氧/好氧条件下染料去除率均低于9.1%,而在外加碳源之后染料去除率明显升高,厌氧条件下染料去除率为90%。厌氧条件下能够处理更高浓度染料废水,染料浓度700 mg/L,去除率50%;好氧条件下染料浓度50~200 mg/L,染料去除率66%~12.7%;厌氧/好氧时染料去除率在厌氧段高。紫外-可见全波段扫描可知,在厌氧条件下染料在224 nm、256 nm、289 nm、416 nm的特征吸收峰或是降低或是消失。     

C.I.酸性黄23的合成工艺

本文介绍了用对氨基苯磺酸重氮盐与乙酰丁二酸二甲酯(DMAS)经偶合、脱羧、闭环、再偶合、水解制得C.I.酸性黄23的方法.染料纯度达99%,含量达到90%以上,溶解度可以达到200 g/L,各方面应用性能好;采用纳滤膜分离技术和喷雾干燥工艺,减少了"三废"排放.     

松木粉制备高比表面积炭基固体酸催化剂

以一种廉价的农林废弃物——松木粉为原料,首先经过炭化和活化处理,制备活性炭,再通过苯磺酸重氮盐还原法处理活性炭引入磺酸基团（—SO3H）,从而制备出具有高比表面积的炭基固体酸催化剂（AC-SO3H）。其比表面积达到1364 m2/g,磺酸基密度为1.36 mmol/g。以乙酸的酯化反应考察了炭基固体酸催化剂的催化活性,并与Amberlyst-15、Nafion NR50以及Nafion SAC-13等几种固体酸催化剂进行了比较。实验结果表明,炭基固体酸催化剂的催化活性仅略低于Amberlyst-15,高于Nafion NR50和Nafion SAC-13,炭基固体酸催化剂的成本也远远低于Nafion NR50和NafionSAC-13。研究结果表明,以松木粉为原料,通过炭化、活化和磺化处理能够得到性能优异且成本低廉的炭基固体酸催化剂。     

松木粉制备高比表面积炭基固体酸催化剂

以一种廉价的农林废弃物——松木粉为原料,首先经过炭化和活化处理,制备活性炭,再通过苯磺酸重氮盐还原法处理活性炭引入磺酸基团(—SO₃H),从而制备出具有高比表面积的炭基固体酸催化剂(AC-SO₃H)。其比表面积达到 1364 m²/g,磺酸基密度为 1.36 mmol/g。以乙酸的酯化反应考察了炭基固体酸催化剂的催化活性,并与Amberlyst-15、Nafion NR50以及Nafion SAC-13等几种固体酸催化剂进行了比较。实验结果表明,炭基固体酸催化剂的催化活性仅略低于Amberlyst-15,高于Nafion NR50和Nafion SAC-13,炭基固体酸催化剂的成本也远远低于Nafion NR50和Nafion SAC-13。研究结果表明,以松木粉为原料,通过炭化、活化和磺化处理能够得到性能优异且成本低廉的炭基固体酸催化剂。     

Effect of Long-Term Forest Fertilization on Scots Pine Xylem Quality and Wood Borer Performance

We tested whether changes in long-term nutrient availability would affect the xylem quality and characteristics of Scots pine trees as a food source for the larvae of the xylophagous wood borer Hylotrupes bajulus L. (Cerambycidae). We looked for an effect of host plant growth and xylem structural traits on H. bajulus larval performance, and looked for delayed effects of long-term forest fertilization on xylem chemical quality. In general, larval performance was dependent on larval developmental stage. However, the growth of larvae also varied with host plant quality (increases in the concentration of nitrogen and carbon-based secondary compounds of xylem were correlated with a decrease in the larval growth rate). The greater annual growth of trees reduced tracheid length and correlated positively with second-instar H. bajulus growth rate. This is consistent with the hypothesis that intrinsic growth patterns of host plants influence the development of the xylophagous wood borer H. bajulus.