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1.
松针提取物和杨树皮提取物饮料添加剂，在室温避光条件下贮藏，生物活性物质（维生素Ｅ，胡萝卜素和叶绿素等）降低的含量百分率与贮藏时间关系，符合Ｙ＝－ａｘ＾ｂ（０＜ｂ＜１）的变化规律。其降低幅度依赖水分大小和维生素种类不同而各异。在贮藏期间，杨树皮提取物饲料添加剂中生物活性物质损失比松针提取物饲料添加剂多，因此，不同类型的产品，贮藏期应有不同要求。试验结果表明，松针提取物饲料添加剂，贮藏期定为一年期限较 相似文献
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松针叶绿素－胡萝卜素软膏中挥发物质含量与树种有关。分析鉴定表明：马尾松叶绿素－胡萝卜素软膏中挥发物质含量为２％－４％，从该挥发物质分离出的３０个色谱峰中鉴定出２４个化合物，其中主要成分为α－蒎烯（２１．２４％）、β－蒎烯（９．６３％）和长叶烯（２１．８３％）。鉴定出的组分占总挥发物质的９４．１２％；赤松叶绿素－胡萝卜素软膏中挥发物质的含量为３％－５％，从该挥发物质分离出的３０个色谱峰中鉴定出２４个 相似文献
4.
松针叶绿素—胡萝卜素软膏不皂化物质化学组成的研究 总被引：1，自引：0，他引：1
松针叶绿素－胡萝卜素软膏中不皂化物质主要由于倍半萜类，二萜类，三萜类，甾族化合物，脂肪族醇和生育酚等化合物组成，分析鉴定表明，马尾松叶绿素－胡萝卜素软膏中含不抑化物质２２．３０％，其中主要成分为β－谷甾醇（１８．６５％），植醇（９．４６％）和香橙烯（７．９８％）等，共鉴定出３７个化合物，鉴定出的组分占不皂化物质总量的９８．３９％，赤松叶绿素－胡萝卜素软膏中含不皂化物质２１．２０％，其中主要成分为香 相似文献
5.
松针叶绿素－胡萝卜素软膏挥发物质化学组成的研究 总被引：1，自引：0，他引：1
松针叶绿素－胡萝卜素软膏中挥发物质含量与树种有关。分析鉴定表明：马尾松叶绿素－胡萝卜素软膏中挥发物质含量为２％～４％，从该挥发物质分离出的３０个色谱峰中鉴定出２４个化合物，其中主要成分为ａ－蒎烯（２１．２４％）、β－蒎烯（９．６３％）和长叶烯（２１．８３％）。鉴定出的组分占总挥发物质的９４．１２％；赤松叶绿素－胡萝卜素软膏中挥发物质的含量为３％～５％。从该挥发物质分离出的３０个色谱峰中鉴定出２４个化合物，其中主要成分为ａ－揽香烯（２１．９０％）、ａ－香柠檬烯（１４．１６％）和长叶烯（９．７０％），已鉴定组分占总挥发物质的９５．８９％；樟子松叶绿素。胡萝卜素软膏中挥发物质的含量为４％～６％，从该挥发物质分离出的３０个色谱峰中鉴定出２４个化合物，其中主要成分为、木罗烯（１６．２３％）、ａ－草烯（９．２４％）和乙酸龙脑酯（８．２０％）等，鉴定出的组分占总挥发物质的９４．００％ 相似文献
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雪岭云杉针叶叶绿素－胡萝卜素软膏中不皂化物质主要由倍半萜类、二萜类、三萜类、甾类化合物、脂肪族醇和生育酚等化合物组成。分析鉴定表明：雪岭云杉针叶叶绿素－胡萝卜素软膏中含不皂化物质约32．0％（占软膏量），其中主要成分为云氢枞醇（10．24％）、绿叶醇（8．64％）、愈创木醇（6．89％）、β-谷甾醇（6．26％）和菜油甾醇（5．98％）等。分离共鉴定出37个化合物，占不皂化物质总量的93．26％。研究发现，雪岭云杉针叶叶绿素－胡萝卜素软膏的不皂化物质中含有较多的β－谷甾醇和菜油甾醇。 相似文献
7.
雪岭云杉针叶叶绿素—胡萝卜素软膏精油化学组成的研究 总被引：1，自引：1，他引：0
雪岭云杉针叶叶绿素－胡萝卜素软膏中含精油１．５６％，其中主要成分为乙酸冰片酯，α－荣烯，和Δ＾３－蒈烯等。分离共鉴定出２５个化合物，占精油总量的９８．１９％。研究发现，雪岭云杉针叶片叶绿素－胡萝卜软膏的精油中含有大量的乙酸冰片酯，其量超过精油总量的一半，乙酸冰片酯是制造樟脑和香精的好原料。 相似文献
8.
雪岭云杉针叶叶绿素－胡萝卜素软膏中含酸性物质约２２％（占软膏重）,其中脂肪酸占４４．８６％,树脂酸占５２．４９％。该酸性物质经气相色谱和质谱定性,定量分析,共分离出３１个峰,鉴定出２６个化合物,被的组分占酸性物质总量的９７．３５％。其中主要成分为检酸（２１．５５％）,异海松酸（１２．８９％）、油酸（１２．０７％）、亚麻酸（７．３１％）、新纵酸（６．１０％）等。研究发现,雪岭云杉针叶叶绿素－胡萝卜素 相似文献
9.
叶绿素－胡萝卜素中酸性物质主要由脂肪酸和树脂酸组成，其中树脂酸占６０％～７５％，脂肪酸占２０％～３０％。酸性物质中各组成的含量与树种有关。分析鉴定表明，马尾松叶绿素－胡萝卜素软膏中含酸性物质２８．０％（占软膏重），从该酸中分离出３１个色谱峰，鉴定出２５个化合物，其中主要成分为海松酸（１０．９６％）、去氢机酸（１９．０６％）和油酸（８．２９％）等，鉴定出的组分占总酸量的９１．５７％；赤松叶绿素－胡萝卜素软膏中含酸性物质２２．８％（占软膏重），从该酸中分离出３１个色谱峰，鉴定出２５个化合物，其中主要成分为山达海松酸（２９．７５％）和去氢枞酸（２３．５０％）等，鉴定出的组分占总酸量的９８．２０％；樟子松叶绿素－胡萝卜素软膏中含酸性物质２６．４％（占软膏重），从该酸中分离出３１个色谱峰，鉴定出２５个化合物，其中主要成分为松叶酸（３６．０１％）、油酸（１５．６６％）和去氢枞酸（１４．８０％）等，鉴定出的组分占总酸量的９８．３０％。 相似文献
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研究了兰考泡桐（Ｐａｕｌｏｗｎｉａｅｌｏｎｇａｔａ）木片用４种酶液（纤维素酶液ＥＳ２８、半纤维素酶ＥＡｎ７６、木质素酶Ｅ０２５及Ｅ０１４）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）Ｅ０１４、Ｅ０２５、ＥＳ２８、ＥＡｎ７６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５５ＳＲ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，Ｅ０１４及ＥＡｎ７６效果较好，ＥＳ２８则由于纤维素酶对纤维的损伤效果不佳，Ｅ０２５效果则一般。 相似文献
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《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
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《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
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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.
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
20.
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