动态浸提提取栀子黄色素工艺研究

以除油栀子粉为原料,乙醇水溶液为浸提溶剂,进行乙醇回流动态浸提提取栀子黄色素,考察各个因素对栀子黄色素的提取率的影响,并与传统浸提提取工艺对比,说明动态浸提提取工艺的先进性。通过单因素试验和正交试验确定最佳工艺条件为:60%乙醇溶液为浸提溶剂、溶液pH值7.0、提取温度60℃、每次提取时间1h、固液比1∶10g/mL、提取次数2次,在此条件下栀子黄色素的提取率达到94.23%,精制后栀子黄色价70、栀子苷含量0.2%(以色价10计进行换算);同时得到栀子苷和绿原酸,提取率分别为90.81%和85.32%。     

不同工艺提取栀子黄色素的比较研究

比较研究了热提取、超声波提取、微波提取3种不同工艺对栀子黄色素提取效果的影响。热浸提正交试验的最佳工艺条件：70％的乙醇（体积分数，下同）提取1．5h，提取温度30℃，料液比1：25（g：mL，下同），产品的色价为66．45。超声波提取正交试验的最佳工艺条件：80％的乙醇提取20min，料液比1：20，产品的色价为87．77。微波提取单因素试验的最佳工艺条件：提取功率800W，用50％乙醇提取30min，提取温度50℃，料液比1：5，色价为64．14。结果表明：热浸提、超声波提取、微波提取3种方法提取栀子黄色素的色价明显不同，超声波提取的效果最好。     

不同工艺提取栀子黄色素的比较研究

比较研究了热提取、超声波提取、微波提取3种不同工艺对栀子黄色素提取效果的影响.热浸提正交试验的最佳工艺条件:70%的乙醇(体积分数,下同)提取1.5 h,提取温度30 ℃,料液比1:25(g:mL,下同),产品的色价为66.45.超声波提取正交试验的最佳工艺条件:80%的乙醇提取20 min,料液比1:20,产品的色价为87.77.微波提取单因素试验的最佳工艺条件:提取功率800 W,用50%乙醇提取30 min,提取温度50 ℃,料液比1:5,色价为64.14.结果表明:热浸提、超声波提取、微波提取3种方法提取栀子黄色素的色价明显不同,超声波提取的效果最好.     

沙棘黄色素最佳提取条件的研究

采用正交试验法,研究了从沙棘果实中提取天然黄色素最佳条件。结果表明沙棘果实黄色素最优提取条件为：物料杨比１：１５（去籽果实与浸提溶剂９５％乙醇的体积比）,温度６０℃,时间２．５ｈ,在最佳提取条件下浸提沙棘果实两次,提取率可达到９８．６％。     

正交试验法优选仙鹤草中总黄酮的提取工艺

采用正交试验法研究仙鹤草中总黄酮的提取工艺，考察了浸提液浓度、浸提温度、浸提时间、浸提次数、液料比等5个因素对仙鹤草总黄酮含量的影响。确立了仙鹤草总黄酮最佳提取条件为：浸提液体积分数40%，液料比10:1，浸提温度70℃，回流提取3次，每次0.5h。     

亚临界萃取栀子果油工艺条件优化研究

栀子果实是原卫生部公布的第一批药食两用资源之一,也是我国优良的木本油料资源。为推动栀子果高值化利用,利用亚临界技术萃取栀子果油,通过单因素和正交试验对该工艺进行了研究和优化,重点探讨萃取温度、萃取时间、料液比、萃取次数对栀子果提油率的影响。结果表明,栀子果油的最佳亚临界条件为：溶剂丁烷,筛网目数60目,料液比1∶5(g∶mL),萃取温度40℃,萃取时间60 min,萃取4次。在此条件下,栀子果油提取率为93.02%。本研究可为亚临界萃取工艺在栀子果制油领域的推广应用提供一定的技术支撑。     

乙醇提取银杏叶黄酮方法的研究

探讨了乙醇提取银杏叶黄酮的方法。试验结果表明：不同的乙醇浓度、浸提温度、浸提时间、浸提次数、固液比等对银杏叶黄酮提取效果均产生不同程度的影响，其中浓度和温度的影响达显著水平。研究认为银杏叶黄酮乙醇提取法的最佳条件为：用50倍（v／w）的90％乙醇溶液于70℃条件下提取2次，每次2h。     

LSA-10大孔吸附树脂分离纯化栀子黄色素研究

通过静态吸附试验选择对栀子黄色素吸附效果较佳的大孔吸附树脂,然后通过动态吸附试验考察上样流速、上样浓度、洗脱剂对大孔吸附树脂分离纯化栀子黄色素的影响。结果表明,LSA-10大孔吸附树脂能高效分离纯化栀子黄色素。分离纯化条件为:上样液体积与树脂质量的比值为5∶1(mL∶g),上样流速为6mL/min,上样浓度为7mg/mL,先用水洗脱杂质和部分的栀子苷,再用浓度为20%乙醇洗脱栀子苷,最后用浓度为80%的乙醇洗脱栀子黄色素。在此条件下,得到色价为337.5,OD值为0.37的栀子黄色素产品。LSA-10大孔吸附树脂适合于高效分离纯化栀子黄色素。     

中压柱层析法分离白藜芦醇的研究

对虎杖(Polygonum cuspidatum Sieb．et Zucc．)中的白藜芦醇进行了提取分离和含量测定。考察了浸提温度、浸提液浓度、浸提时间和次数、料液比等5个因素对白藜芦醇提取的影响，确立了白藜芦醇最佳提取条件为：浸提液体积分数为95％，浸提温度60℃，料液比11:1，回流提取3次，每次60min。采用中压硅胶柱层析法分离白藜芦醇，产物经重结晶后用高效液相色谱测定含量达99．28％。结果表明所建立的制备及分离纯化工艺可用于白藜芦醇的生产。     

绞股蓝多糖的提取及理化性质研究

采用热水浸提、醇沉法提取绞股蓝多糖，对绞股蓝多糖提取工艺和一般理化性质进行了研究。选择浸提固液比、温度、时间和浸提次数作为单因素进行梯度实验，确定其条件范围，再通过正交实验L9（3^4）进一步确定绞股蓝水溶性多糖最佳提取工艺条件。结果表明最佳提取工艺为：固液比1：40、浸提温度85℃、浸提时间2h、反复浸提2次。理化性质结果表明提取的绞股蓝多糖中含有多肽和AA，为蛋白质复合多糖。     

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.