宽叶短梗南蛇藤的三萜类化学成分的研究

利用硅胶和凝胶色谱Sephadex LH-20柱层析技术从宽叶短梗南蛇藤中分离得到了9个三萜类化合物,经核磁共振、质谱等检测方法鉴定为β-香树脂醇、齐墩果酸、12-齐墩果烯-3-酮、12-齐墩果烯-3β,11β-二醇、羽扇豆醇;20(29)-羽扇豆烯-3-酮、20(30)-羽扇豆烯-3β,29-二醇、29-羟基-20(30)-羽扇豆烯-3-酮、羽扇豆醇棕榈酸酯。     

Study on Triterpenoids from Celastrus rosthornianus Loes.var.Loeseneri

利用硅胶和凝胶色谱Sephadex LH-20柱层析技术从宽叶短梗南蛇藤中分离得到了9个三萜类化合物,经核磁共振、质谱等检测方法鉴定为β-香树脂醇、齐墩果酸、12-齐墩果烯-3-酮、12-齐墩果烯-3β,11β-二醇、羽扇豆醇,20(29)-羽扇豆烯-3-酮、20(30)-羽扇豆烯-3β,29-二醇、29-羟基-20(30)-羽扇豆烯-3-酮、羽扇豆醇棕榈酸酯.     

天目木兰的挥发性化学成分

用水浴加热－反相柱吸附提取天目木兰（Magnolia amoena Cheng)的挥发性物质，用GC－MS对其化学成分和相对含量进行了系统分析，得到27个组分，鉴定出23种化合物，其中主要成分为α－蒎烯，β－蒎烯，茨烯，β－月桂烯，D－柠檬烯，鞋葑酮，十八烷等。     

望春玉兰精油化学成分研究

采用水中蒸馏法蒸取木兰科植物望春玉兰的花蕾（辛夷）和鲜花的精油，用ＧＣ面积归一化法和ＧＣ／ＭＳ定性法进行其化学成分的定性和定量研究。结果表明：望春玉兰花蕾含油量高达３．１％，有独特香气，主含α－蒎烯、桧烯、柠檬烯、桉叶油素、松油醇、依兰油烯和桉叶醇等成分，总量占全油９３％以上。鲜花含油量约０．２％，香气宜人，主含α－蒎烯、桧烯、月桂烯、桉叶油素、松油醇、乙酸松油酯和依兰油烯等成分，总量占全油９５％     

β—蒎烯合成紫苏醇的研究

研究β－蒎烯制备紫苏醇过程中的各种影响因素。探讨了β－蒎烯的四醋酸铅氧化，异构，皂化等合成紫苏醇的工艺条件及产品质量分析，结果表明，投料比：β－蒎烯：四氧化三铅：冰醋酸为１：１：１６，温度为６０±２℃时氧化１ｈ；１６０－１７０℃异构１０－１２ｈ；７８℃皂化１ｈ，可得纯度为８４．５％的紫苏醇。产品质量与国外相比基本一致。为紫苏醇产品的工业化提供了依据。     

β－蒎烯合成紫苏醇的研究

研究β－蒎烯制备紫苏醇过程中的各种影响因素。探讨了β－蒎烯的四醋酸铅氧化、异构、皂化等合成紫苏醇的工艺条件及产品质量分析，结果表明，投料比：β－蒎烯：四氧化三铅：冰醋酸为１：１：１６、温度为６０士２℃时氧化１ｈ；１６０～１７０℃异构１０～１２ｈ；７８℃皂化１ｈ，可得纯度为８４．５％的紫苏醇。产品质量与国外相比基本一致。为紫苏醇产品的工业化提供了依据。     

元宝枫、雪松挥发物释放的昼夜节律

【目的】元宝枫、雪松是华北地区常见的绿化树种,阔叶树和针叶树的典型代表,研究其挥发物释放规律并分析其对环境的影响,通过树种合理配置,科学指导绿地游憩林建设,创造更有利于人体健康的绿地环境。【方法】采用固相微萃取结合气质联用仪( SPME-GC-MS),选择生长健康的多年生元宝枫、雪松植株,摘取当年生向阳叶片与枝叶,在7月中旬从8：00—次日5：00,每隔3 h测定其挥发物成分与含量,同时同步测定植株生长环境的温度与湿度。采用 SPSS软件对各数据进行整理分析。【结果】1)元宝枫叶片挥发物主要成分是 C6,C8的酯、醇、醛和萜烯类化合物,乙酸叶醇酯、乙酸己酯、3－己烯醇、3－己烯醛和β－石竹烯约占挥发物总量的70.0%以上,使叶片呈现青叶香。各化合物的释放规律不同,主要成分 C8酯类化合物释放高峰在14：00,低谷在5：00; C15倍半萜类化合物释放呈现“2峰2谷”型,高峰在17：00和5：00左右,低谷出现在8：00和23：00左右。相关分析表明,3－己烯醛与3－己烯醇极显著正相关,乙酸叶醇酯与3－己烯醛、3－己烯醇极显著负相关,其他挥发物间无显著相关。2)雪松枝叶挥发物主要是萜烯类物质,相对含量达84.0%以上,主要成分是α、β－蒎烯、β－月桂烯、D －柠檬烯、β－石竹烯、吉马烯 D,使雪松枝叶呈现树脂香。各化合物的释放规律亦不同,大多数单萜物质如α、β－蒎烯、β－月桂烯、D－柠檬烯等,释放高峰在14：00左右,低谷出现在23：00—次日2：00;倍半萜类物质如β－石竹烯、吉马烯 D释放高峰在17：00和2：00,23：00和5：00则达最低。相关分析表明,α、β－蒎烯、β－月桂烯、D －柠檬烯等4种单萜化合物相关性较高;β－石竹烯与吉马烯 D 极显著相关,与单萜无显著相关。3)挥发物的释放除具有昼夜节律外也受到外界环境的影响,相关分析表明,挥发物总峰面积与温度呈正相关,与相对湿度呈负相关。【结论】元宝枫叶片挥发物以 C8的酯类为主,雪松枝叶挥发物以 C10,C15的萜烯类为主,这与挥发物合成途径有关,各挥发物释放具有不同的昼夜节律性。通常在一定范围内随温度升高、相对湿度减小,挥发物释放量增加。     

一种合成蒎酮酸新方法的研究

为了解决蒎酮酸传统合成方法的条件苛刻和反应时间太长等问题 ,提出用表面活性剂催化氧化α 蒎烯的新方法。主要研究了用十二烷基硫酸钠 (以下简称K1 2 )作催化剂对KMnO4氧化α 蒎烯合成蒎酮酸的反应的催化作用 ,系统探讨了各种反应因素对α 蒎烯氧化反应的影响。研究结果表明 :用表面活性剂K1 2作催化剂对KMnO4氧化α 蒎烯时 ,具有催化剂用量少 (2 % )、反应条件温和 (3 0℃ )、反应时间短 (5 .0～ 5 .5h)和蒎酮酸产率较高 (>60 % )等优点。     

-蒎烯合成3-亚甲基诺蒎酮的研究

研究了以β-蒎烯为原料合成3-亚甲基诺蒎酮的反应.以丙酮为溶剂,以酸性高锰酸钾为氧化剂,β-蒎烯经选择性氧化生成诺蒎酮,研究了氧化剂体系、溶剂体系、反应温度和反应时间对β-蒎烯氧化选择性及诺蒎酮得率的影响.采用KOH为催化剂、37％甲醛水溶液为羟甲基化试剂与诺蒎酮进行羟醛缩合反应得到3-亚甲基诺蒎酮,探讨了诺蒎酮与甲醛物质的量之比、催化剂种类及用量、溶剂体系、反应温度以及反应时间等因素对反应的影响,并采用正交试验法优化了羟醛缩合反应工艺,并确定了适宜的合成工艺条件:n(甲醛)与n(诺蒎酮)为21∶1,n(KOH)与n(诺蒎酮)为1.5∶1,反应在无溶剂存在下进行,反应温度65 qc,反应时间2h.在此工艺条件下,3-亚甲基诺蒎酮得率大于92％.采用GC-MS、FT-IR、1H NMR、13C NMR等手段对合成所得产物的化学结构进行了分析测定.     

挪威云杉幼树韧皮部挥发性物质的测定

通过GC－MS测定挪威云杉幼树主干上部与下部韧皮主要挥发性物质的化学成分与含量，结果表明：挪威云杉幼树的韧皮部挥发性物质的主要成分为α－蒎烯、茨烯、β-蒎烯、月桂烯、3－蒈烯、柠檬烯、β－水芹烯7种单萜化合物。α-蒎烯、β－蒎烯、月桂烯、3－蒈烯、β－水芹烯的含量在上部韧皮与下部韧皮有明显差异，其中上部韧皮部α－蒎烯、β－蒎烯和β－水芹烯的含量明显高于下部主干韧皮部，这为解释松树皮象的取食习性，打下了基础。     

Vasorelaxant activity of some structurally related triterpenic acids from Phoradendron reichenbachianum (Viscaceae) mainly by NO production: ex vivo and in silico studies

The aim of the current study was to investigate the vasorelaxant activity of five structurally-related triterpenic acids namely ursolic (1), moronic (2), morolic (3), betulinic (4) and 3,4-seco-olean-18-ene-3,28-dioic (5) acids. The vasorelaxant effect of compounds 1-5 were determined on endothelium-denuded and endothelium-intact rat aortic rings pre-contracted with noradrenaline (0.1 μM). All compounds showed significant relaxant effect on endothelium-intact vessels in a concentration-dependent manner (p<0.05). Ursolic, moronic and betulinic acids were the most potent vasorelaxant agents with 11.7, 16.11 and 58.46 μM, respectively. Since vasorelaxation was blocked by L-NAME, while indomethacin did not inhibit the effect, endothelium-derived nitric oxide seems to be involved in triterpenic 2 and 3 mode of action. Compounds 1-5 were docked with a crystal structure of eNOS. Triterpenes 1-5 showed calculated affinity with eNOS in the C1 and C2 binding pockets, near the catalytic site; Ser248 and Asp480 are the residues that make hydrogen bonds with the triterpene compounds.     

Pentacyclic triterpenes from the resin of Liquidambar formosana

Two new pentacyclic triterpenes and eight known pentacyclic triterpenes were isolated from the petroleum ether extract of Liquidambaris Resina. The structural elucidation of these compounds was determined by spectroscopic data interpretation. Their cytotoxic and antiplatelet aggregation activities were examined to find potent cytotoxic and antiplatelet aggregation compounds from natural resources. The results showed that 3-keto oleane triterpenes had strong cytotoxicity against MDA-MB-435S cancer cells and that 28-carboxyl oleane triterpenes possessed significant inhibition of platelet aggregation induced by ADP.     

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.     

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。     

Risk Perception Among Non-industrial Private Forest Owners

Based on an enquiry, risk perception among non-industrial private forest owners is described in relation to climate change and forestry hazards. Of the respondents, 11% took action to remedy the effects of climate change. Out of a given set, hazards were ranked according to each respondent's experience of recent substantial financial loss to the estate and in relation to his or her willingness to make investments aimed at risk reduction. For each hazard, the respondent assessed the risk in four classes ranging from very high to negligible risk. Six hazards were considered most problematic in all three aspects: browsing damage, falling timber prices, damage by wind, spruce bark beetle, root rot and pine weevil. A majority of the respondents claimed to take action to reduce the risk associated with at least one hazard, while 35% did not know whether they did. Excluding climate change, the need for decision support was the largest in relation to damage by wind owing to a combination of perceived high risk and a high level of ignorance in relation to whether risk-reducing measures were taken.     

Interactions in decomposition and N mineralization between tropical legume residue components

In situ produced plant residues contain a mixture of different plant components of varying quality. To assess synergistic or antagonistic interactions occurring during the decomposition and mineralization of such mixtures, individual plant parts (stems, leaves, leaf litter and roots) or the mixture of stems, leaves and leaf litter of the agroforestry species pigeonpea (Cajanus cajan) or of crop residues of peanut (Arachis hypogaea) or of the weed hairy indigo (Indigofera hirsuta) were incubated in pots for 19 weeks. Periodically, remaining plant residues were sieved out (>2 mm), weighed and N content as well as soil mineral N determined. Above- and below-ground residues of peanut decomposed fastest and showed the largest N release in agreement with their high N concentration and low-acid detergent fibre (ADF) : N ratio. Hairy indigo was hypothesized to be of lower quality than pigeonpea because of its high-polyphenol content. However, it decomposed faster than pigeonpea, largely because of the higher N and lower lignin concentration of its components. Ranking of individual plant components for N mineralization resulted in the following pattern, leaves > leaf litter > roots > stems. In mixtures of the different plant components a similar species order in decomposition was obtained, e.g. peanut > hairy indigo > pigeonpea. The amount of N released from the mixture was dominated by stem material that comprised 46–61% of the mixture. The interactions in mixtures were relatively small for peanut (generally high-quality components) as well as for pigeonpea (low proportion of high-quality components, i.e. N rich leaf material). However, a positive interaction occurred during later stages of N mineralization in the mixture of hairy indigo as it had a significant proportion of N rich components and absence of highly reactive polyphenols. Thus, for plants with low to intermediate chemical quality attributes, manipulating plant composition (e.g. by varying harvest age, affecting stem and leaf proportions) will be important to obtain significant interactions during decomposition when its components are mixed.