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1.
３，７－二甲基－１，６－辛二烯（１）在固体酸（分子筛，离子膜和离子交换树脂）作用下与甲酸发生环化水合反应，生成１－（３，３－二甲基环己基）乙醇甲酸酯（４ａ）和３，７，７－三甲基环庚醇甲酸酯（５ａ）的混合物，经皂化反应得到相应的醇（４ｂ和５ｂ）。５，７－二甲基－１，６－辛二烯（２）在同样条件下发生类似的反应，生成３，３，５－三甲基环庚醇甲酸酯（６ａ）经皂化生成３，３，５－三甲基环庚醇（６ｂ）。 相似文献
2.
DRS—1高分散松香胶分散剂的合成及应用研究 总被引：3，自引：1，他引：2
合成了碘基琥珀酸ＡＥＯ－９单酯二钠盐,表征了其结构和性质,并将其用作松香分散剂,在中、低转速搅拌和戒严用硬水转相,制备了固含量高「（４５±２）％」、粒度小（０．１－０．５μｍ≥９０％）、稳定性好的松香分散胶。 相似文献
3.
α—蒎烯合成杀虫增效剂的研究 总被引：19，自引：2，他引：17
松节油的主要成分α－蒎烯经异构同时与马来酸酐发生Ｄｉｅｌｓ－Ａｌｄｅｒ反应，生成１－异丙基－４－甲基二环「２，２，２」－５－辛烯－２，３－二羧酸酐。研究影响反应的主要因素：加料顺序，催化剂和助催化剂用量，原料配比，反应时间和反应温度等，得出比较适宜的反应条件。 相似文献
4.
莰烯在硫酸催化下与１，４－丁炔二醇，乙二醇，１，２－丙二醇，１，３－丙二醇反应，分别制得４－冰片氧基－２－丁炔－１－醇，２－冰片氧基乙醇，１－冰片氧基－２－丙醇，３－冰片氧基－１－丙醇，产率分别为５２．７％，５９．７％，４２．６％和４２．０％。上述产物用乙酸酐酯化后得到相应的乙酸酯，其产率分别为８１．３％，７８．９％，７４．８％和７３．６％。所制备的化合物均进行了ＭＳ、ＩＲ、＾１Ｈ ＮＭＲ分析和评 相似文献
5.
１植物名称：四季海棠（Begoniafibrous）。２材料类别：刚展平的嫩叶。３培养条件培养基：（单位：mg／L）（１）MS＋BA３＋２．４－D１，（２）MS＋BA２＋NAA０．２，（３）MS＋BA１＋NAA０．５，（４）MS＋BA１＋NAA０．１，（５）MS＋BA１＋２．４－D０．０５，（６）MS＋BA２＋２．４－D０．０５，（７）MS＋BA０．４＋NAA０．１，（８）１／２MS＋NAA０．５，（９）１／２MS＋BA０．０１。其中蔗糖浓度除培养（８）为２％，其余均为３％，琼脂为０．８％～１．０％，pH值为５．７～５．８，培养温度为２０±４… 相似文献
6.
九嶷香杉精油的化学成分 总被引：1，自引：0，他引：1
采用气相色谱－质谱－计算机（ＧＣ／ＭＳＤ）联用技术．首次研究了九嶷香杉精油的化学成分，鉴定出３８种化合物．主要成分为柏木脑（ｃｅｄｒｏｌ）２４．８％，α－蒎烯（α－ｐｉｎｅｎｅ）１７．５％，柏木烯（α－ｃｅｄｒｅｎｅ）１３．２５％，γ－荜澄茄烯（γ－ｃｅｄｉｎｅｎｅ）７．５％，柠檬烯（ｌｉｍｏｎｅｎｅ）３．５５％，榄香烯（ｅｌｅｍｅｎｅ）３．２％．其次是α－檀香烯（α－ｓａｎｔａｌｅｎｅ），β－檀香醇（β－ｓａｎｔｎｌｏｌ），月桂烯酸（ｍｙｒｃｅｎｏｌ），１．８－桉叶素（１．８－ｃｉｎｅｏｌｅ）等化合物．此外，本文还报道了在杉木精油中首次发现的２１种化合物． 相似文献
7.
杉木绿冠提取物化学组成的研究 总被引：3，自引：2，他引：3
杉木占中国商品材的２０％～２５％，它的树冠占全生物量的１７％，至今未得到合理的有效的利用。本文全面研究了杉木［Ｃｕｎｎｉｎｇｈａｍｉａｌａｎｃｅｏｌａｔａ（Ｌａｍｂ．）Ｈｏｏｋ］绿冠石油醚提取物的化学组成，其总得率为３．５％～６．０％。提取物中：除绿叶蜡外，游离酸占１０％，中性物质占９０％。在游离酸中，２０％是高级脂肪酸，８０％是二萜烯酸，其主要成分是４－表－反式－可姆酸（４－ｅｐｉ－ｔｒａｎｓ－ｃｏｍｍｕｎｉｃａｃｉｄ）又暂名杉叶酸。在中性物质中，有烃类、酯类、醇类、醛类和甾醇类等。酯类占中性物质的６７．３％，其中，聚戊烯醇乙酸酯占７０％。从中分离出来的聚戊烯醇，是含１５～２３个异戊烯基单元的伯醇化合物。其主要组分是聚戊烯醇－２１，占聚戊烯醇总量的２５％；聚戊烯醇－１８占１３％。醇类占中性物质的１０．３％，它的主要组分是４－表－反式－可姆醇，又暂名杉叶醇。甾醇类占１３．３％，主要是β－谷甾醇。其它是可姆醛、植物醇、色素等。 相似文献
8.
将莰烯分别与１，２－丙二醇及１，３－丁二醇加成所得产物１－［（１，７，７－三甲基双环［２，２，１］庚－２－基）氧］２－丙醇及４－［（１，７，７－三甲基双环［２，２，１］庚－２－基）氧］－２－丁醇，氧化得到两只新型的可用作香料的萜醚酮，１－［（１，７，７－三甲基双环［２，２，１］庚－２－基）氧］丙酮，与４－［（１，７，７－三甲基双环［２，２，１］庚－２－基）氧］－２－丁酮。 相似文献
9.
将莰烯分别与１，２－丙二醇及１，３－丁二醇加成所得产物１－［（１，７，７－三甲基双环［２，２，１］庚－２－基）氧］２－丙醇及４－［（１，７，７－三甲基双环［２，２，１］庚－２－基）氧］－２－丁醇，氧化得到两只新型的可用作香料的萜醚酮，１－［（１，７，７－三甲基双环［２，２，１］庚－２－基）氧］丙酮，与４－［（１，７，７－三甲基双环［２，２，１］庚－２－基）氧］－２－丁酮。 相似文献
10.
采用完全随机排列的方法并对９个剑麻品种的生物量，纤维率，抗寒性等综合指标进行分析评定，同时以Ｈ．１１６４８为主要试验对象验证生产栽培技术。结果表明（１）Ｈ．１１６４８生长表现最佳，其叶宽较其它参试品种高０．４－１．７ｃｍ，纤维率４．６５％较其它品种高１．９３％－３．４８％，仅比东７４低０．１５％。（２）栽植剑麻合理的整地方式为宽窄行，大行距２．０－３．５ｍ，小行距１．０－２．０ｍ，适宜密度为４５５ 相似文献
11.
《Scandinavian Journal of Forest Research》2012,27(5):427-435
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. 相似文献
12.
《Scandinavian Journal of Forest Research》2012,27(3):206-217
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. 相似文献
13.
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. 相似文献
14.
《Scandinavian Journal of Forest Research》2012,27(2):118-130
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. 相似文献
15.
Steven Maranz Amadou Niang Antoine Kalinganire Djeneba Konaté Bocary Kaya 《Agroforestry Systems》2008,72(3):231-239
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. 相似文献
16.
《Wood material science & engineering》2013,8(2):76-84
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. 相似文献
17.
《Scandinavian Journal of Forest Research》2012,27(1):53-61
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. 相似文献
18.
《Scandinavian Journal of Forest Research》2012,27(1):15-27
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. 相似文献
19.
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。 相似文献
20.
Astra Zaluma Lauma Bruna Darta Klavina Natalija Burnevica Kristine Kenigsvalde Andis Lazdins Talis Gaitnieks 《Forest Pathology》2019,49(6)
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. 相似文献