超临界CO2流体萃取沙棘全果油实验研究

采用1L超临界萃取实验装置，对超临界CO2流体萃取沙棘全果油进行实验研究，分别考察了萃取压力、温度以及萃取时间等条件对萃取率的影响。结果表明：流量为20L／h时，萃取压力为30Mpa，温度为40℃，萃取时间为3h条件下，萃取率可达18％以上。化学成分分析结果表明：沙棘全果油中富含胡萝卜素、甾醇等多种生物活性成分．     

不同取样时期对杜仲、黄柏、厚朴三种皮类药材质量影响的初步研究

对贵州省林业科学研究院树木园内的杜仲林、黄皮树林、凹叶厚朴林随机分别选取6株样树，从2001年9月至2002年8月每月定日取样，用烘干法测定其含水率，用醇溶性浸出物测定法测定其萃取率。结果表明，不同取样时期杜仲、黄柏、厚朴的含水率差异显著，三种药材含水率变化相对一致，在4、5、6、7月含水率较高，9、10月含水率较低。杜仲、黄柏的最佳取皮期为6月，其萃取率分别为7．92％、6．77％；厚朴的最佳取皮期为7月，萃取率为8．93％。     

萃取赖百当及其化学成分研究

用超临界CO2萃取技术，在压力28MPa、温度40℃、反应时间3h及CO2流量30L／h的条件下，对岩蔷薇(Cistus labdaniferus L．)的枝叶进行萃取，得到赖百当(Labdanum)萃取物。并以苯为溶剂，采用索氏抽提法制备赖百当浸膏；用水蒸气蒸馏法提取赖百当精油。对不同提取工艺得到的赖百当产品的得率及质量进行了分析比较，超临界CO2萃取法产品得率最高，为6．6％(苯萃取法为4．8％，水蒸气蒸馏法为0．8％)，且品质优于苯萃取法产品。用GC-MS分别对超临界CO2萃取物和水蒸气蒸馏精油的化学成分及相对含量进行了测定，共鉴定出31种化合物，其中超临界CO2萃取物中31种，水蒸气蒸馏精油中26种。     

Effects of Extraction and Refining Technology of Tara Tannin on Complexing Precipitation of Geranium

以秘鲁原产塔拉粉为原料,以矿业生产用硫酸锌锗前液的沉锗率为指标,探讨塔拉单宁的提取、纯化、提取物后处理等条件对提高单宁沉锗率的影响.结果表明:以塔拉粉为原料,有机溶剂(甲醇、乙醇、乙酸乙酯)替代水萃取,提取物的沉锗率均大于98％；提取物分别经活性炭脱胶,盐析水洗脱胶,以1％氯化铵和1％次氮基三乙酸进行络合处理,均能有效地降低产物的非单宁成分,提升沉锗效率,可满足工业化应用的要求；当使用塔拉粉与倍花粉的质量比8∶2为混合原料,并对萃取浓胶进行络合处理制成的沉锗剂,沉锗率为99.05％,有助于产物成本的降低和沉锗效率的提高.     

萃取大红袍花椒挥发油的研究

利用超临界CO2萃取装置，采用动态萃取的方法，研究了压力、温度、萃取时间等因子对花椒挥发油萃取的影响，为规模化生产及其相关研究提供了科学依据。研究表明，样品200g粒度40目，最佳的萃取条件为：压力33MPa，温度55℃，时间1．0h，花椒挥发油萃取率为10．2％。气-质联用分析花椒挥发油结果表明，挥发油为3-甲基-2氮杂芴、γ-萜品烯、3-蒈烯等31种化舍物组成。其中3-甲基-2-氮杂芴含量最高，达到18．63％。     

超临界二氧化碳萃取杨梅仁油的研究

采用超临界C02流体萃取技术对杨梅仁中杨梅仁油的提取工艺进行优化研究。运用L9（3^4）正交表，探讨各因素对萃取效果的影响，并采用气-质联用仪对杨梅仁油的成分进行分析。结果表明：超临界CO2流体萃取得到的杨梅仁油品质好，在萃取压力35MPa、萃取温度50℃、萃取时间60min、c02流量30L／h、分离温度30℃时效果最佳，得率高达33．52％；杨梅仁油中脂肪酸以油酸、亚油酸为主，不饱和脂肪酸含量在83％以上，是一种质量很好的保健油。     

石煤钒矿清洁生产绿色提钒工艺研究

指出了陕西五洲矿业股份有限公司原生产工艺采用"浸出—固液分离—氨水中和—萃取反萃取—铵盐沉钒",存在浸出率、萃取率低、废水氨氮含量高、废水处理成本高、废水回用后对生产指标影响较大等问题。为解决这些问题,经过试验研究,采用石灰石替代氨水中和萃取液,对浸出工段添加高效浸出剂及开发无铵沉钒技术,最终确定了"高效浸出—石灰石中和萃取原液—萃取反萃取—无铵水解沉钒—选矿废水循环利用"的清洁生产绿色提钒工艺,经试验研究及工业应用结果表明:高效浸出工艺浸出率达90%,石灰石中和后萃取率达99%,无铵水解沉钒率达98%,可得到纯度98%以上的五氧化二钒产品,使选矿废水循环使用实现了实质性零排放。     

中华猕猴桃种子不饱和脂肪酸的成分分析及其萃取工艺研究

用中华猕猴桃(Actinidia chinensis Planch)种子提取不饱和脂肪酸，经分析测试，产品中主要脂肪酸含量为棕榈酸4．82％、硬脂酸3．72％、油酸13．11％、亚油酸19．36％、亚麻酸64．99％、花生四烯酸2．03％。采用正交试验得出最佳萃取工艺为：萃取温度60℃、萃取时间30min、液料比(石油醚：猕猴桃种子，mL：g)4．0：1．0、萃取次数3次，按该工艺条件，萃取平均得率为29．70％。     

微波辅助法萃取香菇柄中多糖工艺的优选

对香菇柄中多糖，采用单因素试验和正交试验，进行了微波辅助萃取其多糖的研究，得到了微波辅助萃取香菇茵柄中多糖的最佳工艺条件：m（水）／m（香菇菌柄粉）=8，微波功率500W，萃取2次，每次萃取40s。萃取液经真空浓缩，活性炭脱色，加入乙醇使多糖沉淀，过滤，沉淀用乙醇洗涤至颜色为灰白色，真空干燥后即为香菇多糖，产率为13．2％，多糖质量分数为90．4％。与直接加热萃取法进行比较，结果表明，微波辅助萃取能大大缩短萃取时间，降低萃取剂用量，并能提高香菇多糖产率。     

异养菌对不同极限黏度无磷聚合物稳锌稳磷性能的影响

研究了不同极限黏度无磷聚合物AA/AMPS/HPA在含异养菌循环水中对Zn2＋和PO3-4的稳定性能，结果表明：极限粘度不同AA/AMPS/HPA对Zn2＋和PO3-4的稳定性能差别不大；在Ca2＋1000mg/L、碱度280mg/L条件下，异养菌对AA/AMPS/HPA稳定锌盐性能的影响较小，46d后稳锌率为75％左右；该条件下异养菌对AA/AMPS/HPA稳定磷酸盐性能的影响较大，46d后稳磷率仅为65％左右；当配水碱度增加到900mg/L后AA/AMPS/HPA对Zn2＋和PO3-4的稳定效果均较差，稳锌率和稳磷率分别为45％和40％。     

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。     

Natural Regeneration in Clear-cuts: Effects of Scarification,Slash Removal and Clear-cut Age

The effects of soil scarification (mounding), slash removal and clear-cut age on the natural regeneration in clear-cuts was evaluated using data from four sites in southern Sweden. The treatments were carried out during a good seed and establishment year for birch ( Betula pubescens Ehrh. and B. pendula Roth). Scarification had the strongest positive effect on the density of naturally regenerated seedlings, especially in birch, but also in pine ( Pinus sylvestris L.) and spruce [ Picea abies (L.) Karst]. Slash removal had a positive effect on birch density. No statistically significant effect of clear-cut age was found. In addition, no statistically significant interactions between clear-cut age and scarification or slash removal were found. The ingrowth of field vegetation was the fastest in areas that were not scarified, less rapid in areas scarified on old clear-cuts, and the slowest after scarification in fresh clear-cuts. In conclusion, it may be possible to control the density of birch during a good establishment year for birch. If birch is desired, the best combination of treatments is to remove the slash and scarify; otherwise, these treatments should be avoided.     

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.     

Pasture production and tree growth in a young pine plantation fertilized with inorganic fertilizers and milk sewage in northwestern Spain

The use of organic waste materials such as milk sewage as an organic fertilizer could have the dual advantages of organic-waste disposal and reduced dependence on inorganic fertilizers. The effects of fertilization with (1) conventional mineral fertilization, (2) milk sewage sludge at 40 kg N ha⁻¹ target rate and (3) no fertilization on pasture production and tree growth were examined in an experiment consisting of two pasture mixtures under a one-year-old Pinus radiata plantation with a density of 2500 trees ha⁻¹. The two pasture mixtures were: (1) Dactylis glomerata L. var. saborto (25 kg ha⁻¹) + Trifolium repens L. group Ladino (4 kg ha⁻¹) + Trifolium pratense L. var. Marino (1 kg ha⁻¹); (2) Lolium perenne L. var. Tove (25 kg ha⁻¹) + Trifolium repens L. group Ladino (4 kg ha⁻¹) + Trifolium pratense L. var. Marino (1 kg ha⁻¹). The experiment began in the spring of 1995 using a randomized block design with three replicates in Castro Riberas de Lea (Lugo, Galicia, north-western Spain). Plot size was 12 × 8 m², with a 1 m buffer strip between plots. Two-year data showed that fertilization with either material had a positive effect on pasture production, with no significant difference between the two fertilization treatments. Tree growth in the milk sewage sludge plot was significantly higher than in the control plots. Inorganic fertilization increased pasture production, but affected tree growth negatively. The results show that milk sewage sludge could be used as a fertilizer in silvo-pastoral systems. This revised version was published online in June 2006 with corrections to the Cover Date.