马尾松针叶软膏制备维生素E浓缩物的研究

以马尾松针叶软膏为原料，通过化学方法对其中的植醇进行浓缩，然后与２，３，５三甲基氢醌经催化缩合，得到α生育酚浓缩物；再经甲醇提取、酯化及真空蒸馏制得维生素Ｅ浓缩物。主要讨论了合成α生育酚浓缩物的影响因素如原料配比、催化剂种类和用量、反应条件等。分析表明，最终产物中的维生素Ｅ含量高于５０％。     

要重视沙棘造林

<正> 在森林改良土壤实验中可广泛栽培的有前途的果树—浆果人工林中,沙棘占有特殊地位。它的果实(浆果,通常在8月末或9月成熟)具有珍贵的医药和食用价值。果实内的维生素和其他的生命活性物质比黑茶藤子多5倍,比甜橙多14倍。用沙棘浆果制成沙棘油,对加速治愈皮肤各种烧伤、放射病、皮炎和其他皮肤疾患,以及胃病和十二指肠病有特效,可惜目前生产很少。沙棘油是宝贵的生命活性物质——类胡萝卜素(维生素原A)、生育醇(维生素E)、多不饱和脂肪酸(维生素F)、磷脂(卵磷脂等)、甾醇的最主要的浓缩物,对预防动脉粥样硬化的发展、心脏局部贫血病、调整血压、改善全身的自我感觉等都起重要的作用。经加工后的沙棘浆果对增强视力和使青光眼的内眼压正常化具有有效作用。     

怎样合理开发利用沙棘

沙棘(Hippophae rhamnoides),亦称醋柳、酸刺、黑刺等,是一种野生灌木或小乔木,在我国华北、西北、西南和东北近二十个省(区)均有分布。沙棘结成串红黄色浆果,具有珍贵价值。沙棘果营养成分全面,其中维生素C、E、A、K等几乎居一切果、菜之冠。例如维C含量竟为猕猴桃的2～3倍,为山楂的20倍！另还含近20种微量元素和20种氨基酸。沙棘果皮、果肉、种籽以至茎皮中都含油,果实含油率约为10％。沙棘油是各种生命活性物质的浓缩物,可抗辐射,抗疲劳,全面增强肌体活力,是现代医     

森林生物量资源

全球生物量(1975)为1841×10~9吨,其中海洋生物量为3.9×10~9吨,森林生物量为1650×10~9吨,森林面积在地球上约占10％,而生物量约占全球89.6％。若以1公斤干物质相当于4700卡热能计算,全世界森林(1975)可生产热能347×10~(15)卡,这个数     

芬兰塑料大棚桦木种子园

桦木是芬兰主要用材树种之一,占全国森林资源的16％。为加快桦木良种化的速度,芬兰于1972年4月建立一座塑料大棚桦木种子园。在塑料大棚内栽植了125株最优的1-3年生(即播种1年,移栽3年)桦木实生苗。这125株苗木是从930个子代的1.9万株苗木中挑选出来的。1974年从这个塑料大棚桦木种子园采种43公斤,1975年采种63公斤,预计不久每年可采种约100公斤(约有2亿粒),将满足芬兰全国桦木造林用种子之需。据初步测定,用这样的种子造林比用一般种子造林高生长率可增加25％。     

蚕蛹深加工前景广阔

我国有丰富的蚕资源,每年有近10万吨蚕蛹未得到充分利用,多被用于饲料添加剂。据化验测定,普通蚕蛹的粗蛋白质含量50～60％(脱脂蚕蛹高达71～89％),粗脂肪25～26％(脱脂蚕蛹1～2.45％),粗纤维3.4～3.6％(脱脂蚕蛹6％),粗灰份3.8～5.4％(脱脂蚕蛹0.95～5.8％)。每100公斤蚕蛹粉所含蛋白质相当于85公斤瘦猪肉、98公斤鸡蛋、10公斤鲫鱼所含的蛋白质.每100公斤蚕蛹粉的脂肪含量,相当于32公斤     

三倍体毛白杨苗期虫害防治技术

1.地下害虫。危害三倍体毛白杨幼苗的地下害虫主要是蛴螬和金针虫。在整地深耕时,按以下方法配成毒饵每亩撒施2公斤。 (1) 用50％甲胺磷或40％氧化乐果乳油50毫升兑适量水,拌炒熟粗玉米面或炒熟粉碎花生饼5公斤。 (2) 90％敌百虫50毫升,加热水150毫升拌炒熟的麦麸或米糠2.5～4公斤。 (3) 50％辛硫磷乳油50毫升加适量水拌炒熟的粗玉米面、麦麸、米糠或粉碎的豆饼、花生饼4～5公斤。 如果在整地深耕时,没有采取以上措施,可在苗     

颗粒绿茶生产技术

生产颗粒绿茶,只需在原有传统绿茶机械基础上,增加转子揉切机,投入不多,却能增加收益。一、初制机械设备1.70型滚筒杀青机(浙江省茶机工业公司杭州富阳茶叶机械总厂可供)1台,台时产量100￣150公斤,安装吸风排湿装置的为好。2.55型揉捻机4￣6台,台时产量约70公斤。3.芙蓉705型转子机1台(江苏省宜兴市芙蓉茶场生产),台时通过量约500公斤。4.30型解块分筛机1台,配5孔筛网,台时产量约500公斤。5.16型自动烘干机1台,应配置相匹配的热风炉,台时产量约60公斤。二、精制机械设备1.36型平面圆筛机1台,台时通过量为500公斤左右。筛网配置8、10、12、16…     

滑菇栽培及加工技术

滑菇喜低温,可采用开放式栽培,管理方法简单。现将栽培技术介绍如下: 1 播种期滑菇菌丝耐低温,其发育起点为5℃,适宜在晚冬或早春播种。其菌丝发育完全靠自然温度,开始只需保持培养基不结冻即可。 2 原料配比 2.1 木屑(不能含针叶树种)100公斤、麦麸20公斤,石膏粉1公斤。 2.2 木屑78％,米糠20％,糖1％,石膏粉1％。 2.3 木屑90％,米糠8％,玉米面2％。根据当地条件,任选其一配方,按比例准确称取后,充分拌匀,加水(糖溶解在水中)调至含水量为60～65％。     

腰果壳液的蒸馏及其馏分的色-质谱联用分析

用蒸馏法从商品腰果壳液中提取主成分腰果酚。采用色谱-质谱-计算机联用仪对蒸馏馏分进行定性和半定量分析。结果表明,常压或减压蒸馏均能得到腰果壳液的主成分。减压蒸馏可大大提高馏分的得率,在真空度1999.832Pa进行减压蒸馏时,最高得率为72％;得率约60％时,其残留物尚能得以利用。蒸馏馏分为淡黄色油状液体,其中含有约75％的腰果酚、10％其它酚类化合物和15％的烷基苯;其颜色比原腰果壳液浅得多。该主馏分腰果酚带有饱和(10％)、单烯(59.9％)、双烯(17.7％)和三烯(12.5％)的长侧碳链,其总不饱和度比原腰果壳液主成分低。     

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.     

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.     

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.