松节油基阴离子表面活性剂的合成研究

以松节油、马来酸酐(MA)和环氧乙烷(EO)为基本原料,通过加成、酯化及聚合等化学反应,分别合成了松节油基聚氧乙烯酯(TMEE)和松节油基阴离子型表面活性剂(TMAS).重点讨论了不同原料配比、催化剂、反应温度及反应时间等因素对TMAS合成反应的影响,并对表面活性剂的红外光谱进行了解析.     

松节油改性聚氨酯涂料的合成研究

以松节油为基本原料，通过D-A加成反应和聚酯化反应合成了松节油伯羟基聚酯多元醇，并用多异氰酸酯组分将其交联固化，制备了松节油改性聚氨酯涂料。重点讨论了不同原料配比、反应时间等因素对聚酯化反应的影响，并对松节油改性聚氨酯涂料的性能进行了测试。     

松节油合成生物活性角鲨烯反应路线的研究

基于对深海鲨鱼肝油中的珍贵天然生物活性化合物角鲨烯以及我国丰富的天然单萜烯资源松节油化学结构的对比研究．在考察献资料和现有研究成果的基础上．作创新性地提出了从松节油合成角鲨烯的构想．其可行的合成路线主要包括松节油(蒎烯)→蒎烷→氢过氧化蒎烷→蒎醇→芳樟醇→香叶基丙酮→橙花叔醇→金合欢醇→金合欢基溴→角鲨烯等9步化学反应。在已有研究基础上．通过对合成金合欢基溴及金合欢基溴偶联的反应进行重点的详细研究后．贯通了合成路线．实现了从可再生天然精油松节油合成珍稀资源角鲨烯的独创设想．获得了目的产物角鲨烯。本概述了合成路线中每一步合成反应的现状和要点。     

N—脱氢枞基氨基酸类两性表面活性剂合成及其结构与性质关系研究

以脱氢枞胺为原料合成了四种氨基酸类两性表面活性剂，它们分别是Ｎ－脱氢枞基氨基 内、丙酸钠、乙基磺酸钠、（２－羟基Ｏ丙基磺酸钠。对产物结构进行了鉴定，测定了它们的表面物理性质及抗菌性能，并对结构与性质之间关系进行了探索。     

松节油合成生物活性角鲨烯反应路线的研究

基于对深海鲨鱼肝油中的珍贵天然生物活性化合物角鲨烯以及我国丰富的天然单萜烯资源松节油化学结构的对比研究,在考察文献资料和现有研究成果的基础上,作者创新性地提出了从松节油合成角鲨烯的构想,其可行的合成路线主要包括松节油(蒎烯)→蒎烷→氢过氧化蒎烷→蒎醇→芳樟醇→香叶基丙酮→橙花叔醇→金合欢醇→金合欢基溴→角鲨烯等9步化学反应.在已有研究基础上,通过对合成金合欢基溴及金合欢基溴偶联的反应进行重点的详细研究后,贯通了合成路线,实现了从可再生天然精油松节油合成珍稀资源角鲨烯的独创设想,获得了目的产物角鲨烯.本文概述了合成路线中每一步合成反应的现状和要点.     

以松节油为原料制备系列合成香料

以松节油为原料制备系列合成香料郭伟玲，刘德臣，孔中东，马家恒（黑龙江省石油化学研究所）（东北林业大学）（黑龙江省森工总局）松节油是存在于自然界中产量最大、价格最便宜的精油。我国有丰富的松节油资源，年产量５～６万ｔ，居世界第２位。松节油是多种萜烯混合物...     

表面活性剂促进纤维原料酶解转化过程研究进展

尽管目前纤维原料酶解转化乙醇研究已取得较大进展,但是仍需利用各种技术降低转化成本以实现其商业化生产。如:采用有效的预处理方法以改变纤维原料高度复杂的内部结构;降低生物转化过程中所需化学品的用量和能耗;实现在低酶用量下纤维原料向目标产物的高效转化等。笔者从添加表面活性剂的角度讨论了对纤维原料酶解转化的影响。在纤维酶解转化过程中添加表面活性剂能够降低木质素对酶解的抑制作用,增强纤维素的可及度,改善底物的润湿性和降低反应体系界面张力,从而提高酶解效率、降低纤维素酶用量,实现纤维原料向目标产物的高效转化。综述了合成表面活性剂、天然表面活性剂和生物表面活性剂等种类及其性质,以及不同类型表面活性剂在纤维原料酶解转化中的应用,并从对纤维原料底物性质、纤维素酶及酶解体系的影响等方面,总结比较了表面活性剂在纤维酶解转化过程中的促进作用及机理。充分利用富含天然皂苷的农林废弃物或木质素磺酸盐等工业废弃物辅助纤维原料酶解转化,具有重要的环保意义和经济效益。     

表面活性剂对有机硅包覆松香基环氧树脂微胶囊的影响

以马来海松酸酐缩水甘油酯型环氧树脂(MPTGE)为原料与聚乙二醇反应合成了一种与MPTGE具有相似分子结构的松香基非离子型表面活性剂(MP),再以MP及其它5种常用表面活性剂乳化MPTGE作为嚢芯,正硅酸四乙酯(TEOS)为囊壁,采用溶胶-凝胶法制备了一种新型有机硅包覆环氧树脂微胶囊。研究了不同种类及用量的表面活性剂对微胶囊粒径及其分布的影响,并通过光学显微镜、扫描电镜、Zeta粒径测定等分析方法表征了微胶囊的表面形貌、粒径尺寸及分布。结果表明,表面活性剂MP有助于有机硅包覆环氧树脂微胶囊的形成;在MP用量为16.7%(质量分数)时,制备的微胶囊表面光滑致密、分散均匀。     

松香基聚葡萄糖苷的合成及性能

以歧化松香醇为原料采用转糖苷法合成了新的非离子表面活性剂松香基聚葡萄糖苷(RPG),研究了丁糖苷的合成反应及苷交换反应。适宜的反应条件为:丁醇与葡萄糖的摩尔比为4∶1,对甲苯磺酸作催化剂,用量为葡萄糖质量的0.5%,生成丁糖苷的温度110℃,苷交换温度140℃,糖转化率达99.5%。研究了产物的表面物理化学性能及环氧乙烷聚合度(n)对产物表面物理化学性能的影响。RPG和RP相比,乳化力(EP)和泡沫性能(FP)有明显的提高。     

顺丁烯二酸酐

顺丁烯二酸酐顺丁烯二酸酐（简称顺酐）是重要的有机化工原料，是合成醇酸树脂、聚脂树脂及涂料的主要原料，还用于增剂型、绝缘漆、医药、农药、试剂、表面活性剂等方面，具有广阔的发展前景。湖北广水市拟建年生产２０００吨顺酐的生产线，需投资９９８万元，主要用于购...     

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.     

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.     

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.     

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。     

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.