造纸车间主要设备及工艺流程简介

方正林业造纸厂是我国林业系统最大的造纸厂，产品品种为挂面牛皮箱板纸，设计规模为３．４万ｔ／年。造纸车间原料为：以制浆车间来的阔叶材半化学浆为底浆，以针叶材化学浆为面浆。１打浆工段１．１主要设备①ＺＮＷ２１型圆网浓缩机面积５ｍ２；转鼓规格１５００ｍｍ×１０６５ｍｍ；生产能力３～３．５ｔ／ｍ２·ｄ；进浆浓度１％～２％，出浆浓度４％。②ＺＮＷ２３型圆网浓缩机面积１５ｍ２；转鼓规格１５００ｍｍ×３３３０ｍｍ；生产能力３～３．５ｔ／ｍ２·ｄ；进浆浓度１％～２％；出浆浓度４％。③４５０双盘磨ＺＤＰ-１１型，…     

火炬松纸浆林材性变异和优质原料培育期的确定*

１６年生火炬松纸浆材性状研究表明：管胞长度径向呈递增稳定的模式，纵向呈递减变化；其长宽比变异类似于管胞长度的变化；管胞长度变化范围为１．４０３～４．４５６ｍｍ，长宽比为４６．７～７０．１，腔径比为０．７１１～０．７８６，壁腔比为０．３８１～０．４９６。基本密度径向由０．３２４ｇ／ｃｍ３递增到０．４２８ｇ／ｃｍ３；纵向递减，其均值变动于０．３１４～０．４０１ｇ／ｃｍ２；株间木材密度均值与管胞长度两性状不相关。纤维素含量由髓心附近３７．０４％递增到树皮附近４３．９１％，木素、多缩戊糖含量分别由２８．７８％、１４．５９％递减到２５．７４％、１２．０５％，其苯醇抽出物含量变化在２．１２％～８．３８％之间。火炬松木材幼龄期约为１０～１３ａ。基于火炬松木材各树龄材性的变化，结合生长量指标，确定其短周期纸浆林适宜采伐树龄约为１２～１３ａ。     

材性改良研究VI.美洲黑杨×小叶杨新无性系木材性状遗传相关分析

对美洲黑杨×小叶杨新无性系木材性状遗传相关分析结果表明，年轮宽度与早材宽度、晚材宽度遗传相关比较密切；与晚材率之间相关很弱；而年轮密度与早材密度、晚材密度、最小密度及最大密度之间遗传相关密切（ｒｙ＝０．８４－０．９５），与早晚材密度比及木材密度相关很弱；年轮密度与年轮宽度之间呈负弱相关。     

速生材制生物机械浆研究Ⅱ、泡桐(Paulownia elongata)酶液预处理机械浆

研究了兰考泡桐（Ｐａｕｌｏｗｎｉａｅｌｏｎｇａｔａ）木片用４种酶液（纤维素酶液ＥＳ２８、半纤维素酶ＥＡｎ７６、木质素酶Ｅ０２５及Ｅ０１４）预处理制生物机械浆。测定了预处理对木片主要化学组成、磨浆能耗、纸浆强度的影响。结果表明：（１）Ｅ０１４、Ｅ０２５、ＥＳ２８、ＥＡｎ７６预处理后，木片失重３．１８％～３．７２％，其中３．９％～１８．６％为木质素损失，纤维素损失则高达３８．２％～４６．２％；（２）磨浆度为５５ＳＲ时，４种酶液可节省能耗２．０％～７．０％，裂断长变化为－１８．１％～７．９％，耐破度变化为－１３％～７．３％，撕裂度为－１２．９％～８．４％，光学性质（如白度、光散射系数）变化不大，不透明度几乎不变。综合能耗节省与强度性质的提高，Ｅ０１４及ＥＡｎ７６效果较好，ＥＳ２８则由于纤维素酶对纤维的损伤效果不佳，Ｅ０２５效果则一般。     

黑荆木材硫酸盐法制浆试验研究

试验对６年生黑荆木材硫酸盐法制浆工艺进行正交试验，得出最佳制浆工艺为：用碱量１５％，硫化度２０％，最高温度１６５℃，保温时间１２０ｍｉｎ，细浆得率５１．６１％，硬度１２．０８Ｋ值，黑液残碱４．７０ｇ／Ｌ，纸浆纤维平均长度０．８４５μｍ，平均纤维宽度１５．８４μｍ，长宽比为５３．３３，接近黑荆木材的纤维形态；利用该纸浆手工抄纸，定量为５．８６ｇ／ｍ２，纸张拉力为３．３４ｋｇ，裂断长度为３８４２ｍ，表明黑荆木材适宜作为造纸的原料。     

三种速生建筑材料树种制造中纤板的制浆工艺和磨片选型

研究了供制造中密度纤维板用的三种速生建筑材的制浆工艺和磨片齿形。试材树种杉木，火炬松及湿地松；磨片齿形有中细齿、粗齿及中齿三种；木片蒸煮汽压固定为０．４－０．６５ＭＰａ蒸煮时间分别为３，６，９及１２ｍｉｎ，磨盘间隙为０．１ｍｍ。结果表明；三种齿形制浆所得中长纤维（留于３２－１１５目）占总张的５０－７０％，尤以中齿形磨片制浆，效果更好，在３－１２ｍｉｎ的蒸煮时间内，纤维分离效果及制板后板的平面抗拉强     

日本落叶松纸浆材造纸性能及工艺成熟期的研究

通过日本落叶松８、１５、２０、２５年生４种年龄木材物理性能和形态，化学分析及纸浆造纸性能的研究，并与美国，加拿大进口的纸浆比较，认为该树种木材纤维素含量高，纤维长、粗浆得率高达４７．３％，而且制浆容易，成本低，纸浆造纸性能较好，是良好的造纸用材树种。分析确定，日本落叶松纸浆材工艺成熟期为１５￣２０年生。     

黑荆木材及其KP、CTMP的纤维形态研究

研究表明黑荆木材１—３年生密度为０．５９—０．６５ｇ／ｃｍ３，５—１０年生为０．７２ｇ／ｃｍ３；１—７年生木材成分变化不大，纤维素在４５％以上，半纤维素在２５％以下，木素在２１％以下。比较６年生黑荆木材及其ＫＰ、ＣＴＭＰ的纤维形态，纤维长度在０．７６ｍｍ以上的，木材为７２．０４％、Ｋｐ为７２．２２％、ＣＴＭＰ为８２．５８％；平均纤维长度木材为０．８５６ｍｍ、ＫＰ为０．８４５ｍｍ、ＣＴＭＰ为１．１６５ｍｍ；纤维宽度在１２一２４μｍ，木材为９２．６２％、ＫＰ为９２．８６％、ＣＴＭＰ为３４．６３％；平均纤维宽度木材为１５．６μｍ、ＫＰ为１５．８μｍ、ＣＴＭＰ为３０．７μｍ；长宽比木材为５４．９、ＫＰ为５３．３、ＣＴＭＰ为３７．９。     

刚果12号桉的木材性质及制浆试验

进行了５龄刚果１２号桉的木材性质和制浆试验。以胸高圆盘加权平均数为单元，平均导管直径９０μｍ，管孔数１６Ｎ／ｍｍ２；射线数１５Ｎ／ｍｍ；纤维长度０．８６８ｍｍ，壁厚２．９μｍ；组织比量（％）：导管１４．０，薄壁组织２９．８，纤维５６．２；基本比重０．５７７。研究了这些性质的径向变异性。木材强度中等。综纤维素含量７７．６２％，木素含量２５．０９％。烧碱－蒽醌法制浆试验表明，容易成浆，粗浆得率４６．９２％，漂浆白度７３．８％，纸片成型性良好，耐破指数４．５８ｋＰａ·ｍ２／ｇ，撕裂指数７．５３ｍＮ·ｍ２／ｇ。     

楸树造林密度及其效应的研究

楸树造林密度７年试验总结。在７种造林密度中，树高最高（平均５．１３ｍ）的密度为２１ｍ×１ｍ、３ｍ宽窄行，最低（平均４．４０ｍ）的密度为２ｍ×２ｍ，相差１６．６％；最大胸径（平均７．４ｃｍ）和最大单株立木材积（平均０．００８６６ｍ￣３）的密度为３ｍ×４ｍ，最小胸径（平均５．７ｃｍ）和最小单株立木材积（平均０．００４７１ｍ￣３）的密度为２ｍ×２ｍ，胸径相差２９．８％，材积相差８４．９％；密度居中的２ｍ×１ｍ、６ｍ宽窄行及３ｍ×３ｍ，对光照的利用较佳，冠下平均光照强度０．８０—０．９５万勒克司，冠下、株间、行间光照平均透过率分别为１２．４—１４．４％、１６．０—２１．２％、５０．８—５９．１％；２ｍ×１ｍ、６ｍ宽窄行的光台强度较２ｍ×２ｍ增加２０．１％；密度愈小，郁闭愈晚，径阶偏向大径阶分布，密度愈大，郁闭愈早，径阶偏向小径阶分布，并需较早的间伐。     

Browsing Damage on Pine (Pinus sylvestris and P. contorta) by a migrating moose (Alces alces) Population in Winter: Relation to Habitat Composition and Road Barriers

In Scandinavia, moose (Alces alces L.) sometimes cause severe browsing damage to economically-important pine. Moose-vehicle accidents have spurred construction of fences along roads, and these may interfere with moose migration between summer and winter ranges, or the road alone may be a barrier. If this happens and moose build up along roads, landowners may suffer economically. Therefore, this study investigated whether roads, fences or other factors influence the use of young pine stands by moose. Eighty stands along roads in northern Sweden were evaluated in which individually-browsed branches were counted on 9972 pines. Moose browsing was not significantly related to birch (Betula pendula Roth, B. pubescens Ehrh.) density, nor did it differ between pines (Pinus contorta Douglas or P. sylvestris L.). However, increased pine density, site productivity and proximity to a highway were associated with increased browsing. Further large-scale studies are needed to understand moose habitat selection and the effects of roads.     

Effects of Root Freezing on the Physiology and Growth of Picea glauca,Picea mariana and Pinus banksiana Seedlings Under Different Soil Moisture Regimes

The root systems of 2-yr-old Picea glauca, Picea mariana and Pinus banksiana seedlings were submitted to various frost temperatures during an artificial frost to induce different levels of root damage. Frost-damaged and control seedlings were placed in a greenhouse under high and low soil moisture regimes. Seedling growth and physiology were evaluated periodically. Seedling survival was reduced when root damage reached levels of 60-80%. Root systems of all three species showed partial to total recovery by the end of the experiment. In general, root freezing damage caused reductions in seedling growth, with these reductions becoming less significant over time. Root damage had little to no effect on black spruce and jack pine seedling physiology, while white spruce CO 2 uptake decreased with increasing root damage. Shoot nitrogen content of all three species decreased slightly with increasing root damage.     

Decomposition and nutrient loss from prunings of different contour hedgerow species in tea plantations in the sloping highlands of Sri Lanka

Contour hedgerows of multipurpose tree species in the sloping tea lands of Sri Lanka are expected to reduce soil erosion and also add significant amounts of plant nutrients to the soil via periodic prunings. The objective of this experiment was to characterize the biomass decomposition pattern and quantify the amount of nutrients added through prunings of six tree species (Calliandra calothyrsus, Senna spectabilis, Euphatorium innulifolium, Flemingia congesta, Gliricidia sepium and Tithonia diversifolia) currently being used in hedgerows associated with tea. Withered leaf and stem prunings (50 g) were enclosed in 2-mm litter bags, placed at 5-cm depth and retrieved after one, three, six, nine and 12 weeks. Loss of initial dry weight, N, P and K was measured. Single exponential decay function adequately described both dry weight and nutrient loss. Tree species differed significantly in their rate of breakdown with decomposition constants (k) varying from 0.0299 to 0.2006 week⁻¹ for leaves and from 0.0225 to 0.0633 week⁻¹ for stems. Gliricidia showed the highest k for leaves with the rest in the following descending order: Senna > Tithonia ≥ Euphatorium > Calliandra > Flemingia. A similar pattern was observed for loss of all nutrients with Calliandra and Flemingia always having lower k values than the rest. Although N immobilization was not observed, immobilization of P and K was observed during the first week of incubation in some species, particularly in stem prunings. Annual biomass of prunings differed significantly between tree species in the following descending order: Calliandra > Senna > Flemingia > Tithonia > Gliricidia > Euphatorium. Calliandra added the greatest amount of nutrients annually to the soil with Euphatorium adding the least. Calliandra prunings provided the annual total K requirement and 49% of the N requirement of mature tea. However, none of the species provided more than 5% of the P requirement. It is concluded that among the tree species tested, Calliandra and Flemingia are the most suitable for contour hedgerows in tea plantations of this agroclimatic region because of their higher soil nutrient enrichment capacity and slower decomposition rates which would minimize leaching losses. This revised version was published online in June 2006 with corrections to the Cover Date.     

Effects of Seed Weight and Seed Type on Early Seedling Growth of Pinus sylvestris under Harsh and Optimal Conditions

The effects of seed weight and seed type on seedling growth of Pinus sylvestris (L.) were studied by seeding individually weighed orchard and stand seed in different mixtures under harsh (direct seeding in field) and optimal (seeding in nursery) conditions. In the nursery experiment an increase in the seed weight from 3 to 7 mg increased the seedling height by 10-27% and total weight by 27-113%, and decreased the height/diameter ratio by 5-6% after 2 yrs. With elimination of seed weight effects, orchard seedlings were 2% taller than stand seedlings in year 2. Without elimination of seed weight effects, orchard seedlings were 7-13% taller. In the field experiment an increase in the seed weight from 3 to 7 mg increased seedling height by 18-65%, stem volume by 81-274% and the number of top-buds by 23-34% in year 5. After elimination of seed weight effects, orchard seedlings were 7-13% taller than stand seedlings and without elimination of seed weight effects 20-21% taller after 5 yrs. Even after elimination of both seed weight and genetic effects orchard seedlings were 3-9% larger than stand seedlings in the field experiment. In conclusion, the influence of seed weight and seed type on growth traits and slenderness is highly significant and the influence seems to be greater in harsh conditions.     

Modelling of adequate pretwist for obtaining straight timber

Abstract

Wood in general and wooden studs in particular are often distorted owing to uneven shrinkage during the drying process in the sawmill. Twist is often the most detrimental of all types of distortion, and it is caused by spiral grain in combination with variations in moisture content. For sawmills, the objective is to produce dried, straight boards, and one method of dealing with boards with excessive spiral grain is to sort them out and then dry them in a pretwisted position to obtain straight boards after drying. A model using the finite element (FE) method for the simulation of drying twist distortions was first calibrated against laboratory experiments in which boards were dried with and without restraints and pretwists. After the calibration, the FE results were compared with industrial test results for boards that were dried without restraints or with restraints with zero pretwist, i.e. straight restraints. The FE model used an elastic–ideally plastic material model to obtain permanent deformations. The calibration was to set the yield stresses so that there was a good match between FE results and results from the laboratory experiments. The comparison between the industrial test results and the FE results showed that the FE model is capable of realistic simulations of drying boards with and without restraints and presumably also pretwists.     

Potential to harness superior nutritional qualities of exotic baobabs if local adaptation can be conferred through grafting

Baobab leaves form an important part of the local diet in Sahel countries and elsewhere in Africa. Existing leaf nutritional data and agroforestry performance information are based solely on Adansonia digitata L., the baobab of continental Africa. The introduction potential of Adansonia species from the center of diversity in Madagascar and from Australia remains untapped. To assess this potential, the mineral contents and B₁ and B₂ vitamin levels of dried baobab leaves were determined for five-year old trees of A. digitata, A. gibbosa (A. Cunn.) Guymer ex D. Baum, A. rubrostipa Jum. & H. Perrier (syn. A. fony Baill.), A. perrieri Capuron and A. za Baill. grown in an introduction trial in Mali. Nutritional data were evaluated against survival and vigor to identify promising germplasm. Leaf vitamin and crude protein contents were highest in the Madagascar species, especially A. rubrostipa (B₁ 88 mg 100 g⁻¹, B₂ 187 mg 100 g⁻¹, protein 20.7% dry weight). However, the local species far outperformed the introductions in survival, tree height, basal diameter and resistance to termites. We suggest grafting as a way of harnessing the vigor of well-adapted local baobab varieties to the superior nutritional profiles of A. rubrostipa and others. Cross-species grafting tests in Adansonia were successful, thus creating new agroforestry possibilities with different scion/rootstock combinations.     

Growth of Phlebiopsis gigantea in wood of seven conifer species

Heterobasidion parviporum and Heterobasidion annosum are widely distributed root‐rot fungi that infect conifers throughout Europe. Infection of conifer stumps by spores of these pathogens can be controlled by treating fresh stumps with a competing non‐pathogenic fungus, Phlebiopsis gigantea. In this study, growth of three Latvian strains of P. gigantea and the biological control agent ‘Rotstop’ strain was evaluated in stem pieces of Norway spruce, Scots pine, lodgepole pine, Douglas‐fir, Weymouth pine, Siberian larch and Sitka spruce. The growth rates of one H. parviporum and one H. annosum isolate were also measured in the same stem pieces. The growth rate of P. gigantea varied greatly in wood of different conifer species. It was higher in the three pine species, lower in Norway spruce and lowest in Sitka spruce and Siberian larch, and in Douglas‐fir, this fungus did not grow. The largest area of wood occupied by P. gigantea was in lodgepole pine. Growth of Latvian isolates of P. gigantea in the wood of Pinus and Picea species was comparable to that of the Rotstop isolate. Consequently, stump treatment with local P. gigantea isolates should be recommended. However, our results suggest that Douglas‐fir stump treatment against Heterobasidion by P. gigantea may be ineffective and other stump treatment methods should be considered.     

Stand Structure in Pine,Spruce and Deciduous Forests: A Comparison Between Finnish and Russian Karelia

This study investigated the stand structure in pine, spruce and deciduous forests in the border district of Finland and Russia. A total of 46 mature forest stands was selected as pairs, the members of each pair being as similar as possible with respect to their forest site type, age, moisture and topography. The stands were then compared between the two countries by means of basal areas and number of stems. The proportions of dominating tree species were 2-12% lower, and correspondingly the proportions of secondary tree species higher, in Russian forests. The density of the forest stock was also higher in each forest type in Russia. The forests in the two countries differed most radically in terms of the abundance of dead trees. The amount was two to four times higher in Russian deciduous and spruce forests, and in pine forests the difference was 10-fold. The stand structures indicated that Russian coniferous stands, in particular, were more heterogeneous than intensively managed pine and spruce stands in Finland.     

Growth and Terminal Bud Formation in Picea abies Seedlings Grown with Alternating Diurnal Temperature and Different Light Qualities

The root collar diameter and the height:diameter ratio are of particular importance in container-grown seedlings where a high density in the containers may produce spindly seedlings. Temperature regimes and light quality are known to affect plant growth. The aim of this study was to identify responses in Picea abies (L.) Karst. seedlings grown with light providing different red:far-red ratios and under temperature regimes with alternating day (DT) and night temperature (NT) from negative (DT < NT) to positive (DT > NT) difference (DIF) between DT and NT. Experiments were conducted in controlled environment chambers and in a daylight phytotron. Only limited thermoperiodic responses appeared in P . abies seedlings with respect to seedling height and dry weight accumulation. The formation of terminal buds, however, was clearly delayed in seedlings grown at negative DIF. The results indicate a requirement for day extension light that is high in far-red, to prevent terminal bud formation under natural short-day conditions. An extended study should be conducted to clarify the minimum level of light intensity and the optimal light quality needed to prevent terminal bud formation under natural short-day conditions.     

CAD与建筑设计的关系

本文分析了CAD在设计中引起的正面和负面影响,并进行了系统的阐述,从而使设计者在应用中能够保持客观的态度。