星型环氧乳化剂合成及乳液的性能研究

采用自制星型乳化荆合成水性环氧乳液，考察了乳化剂的结构与环氧乳液稳定性及涂膜性能的关系，优化了乳化荆在制备环氧乳液过程中的主要参数。研究结果表明：聚乙二醇和环氧树脂E-20中环氧基与羟基的物质的量比为1．5：1．0、聚乙二醇的相对分子质量为4000、乳化剂用量为10％时，制备的环氧乳液稳定性高、成膜性能优良。     

聚醋酸乙烯酯乳液的改性研究

从聚醋酸乙烯酯的分子结构、性质及其乳液的最低成膜温度出发，以丙烯酸类单体为改性单体，采用均匀设计法来设计合成共聚型乳白胶的配方，对乳液的胶合性能进行检测，对胶合强度进行回归分析，从而得到具有一定使用价值的工艺配方。研究结果表明：当聚乙烯醇的浓度为8．5％、醋酸乙烯与改性单体的比例为75：25、官能性单体的比例为2％、引发剂的比例为2．5％、乳化剂的比例为4％时，其玻璃化温度Tg=2．94℃，干态剪切强度达13MPa以上，木破率达90％以上，湿态剪切强度达4MPa以上，而且胶层的韧性和耐水性得到明显改善。     

明胶接枝共聚物乳液的合成及其对纸张强度的影响

以明胶、丙烯酰胺(AM)、甲基丙烯酰氧乙基三甲基氯化铵(DMC)为原料,在非离子乳化剂、阳离子乳化剂及二者的复合乳化剂的条件下,以氧化-还原引发剂作为引发体系,采用乳液聚合法合成了一系列明胶接枝共聚物乳液。考查了单体的加料方式,不同种类和不同配比的乳化剂对乳液及纸张增强效果的影响。结果表明,单体采用一次性加料,非离子型乳化剂和阳离子型乳化剂复配的情况下,合成的乳液对阔叶材木浆的增强效果最好。当非离子型乳化剂(OP)和阳离子型乳化剂(Y1)按2.5∶7.5(质量比)进行复配所合成的乳液当其用量为1%(相对绝干浆)时,对纸页物理强度提高最大,纸页裂断长、撕裂指数、耐破指数、耐折度相应比空白样提高了23.9%、7.6%、21.2%和186%。     

歧化松香胺Schiff碱-铜配合物催化苯乙烯氧化反应的研究

以H2O2为氧源，研究了歧化松香胺Schiff碱-铜配合物催化苯乙烯的氧化反应，探讨了溶剂种类、催化荆用量、氧化剂用量、反应温度及反应时间对催化氧化反应的影响。结果表明，催化氧化反应的较佳条件是：以1，4-二氧杂环己烷为溶剂，苯乙烯5.000g，催化剂Schiff碱-铜配合物用量为苯乙烯质量的0．5％，质量分数为30％的H20：15mL，80℃反应6h。苯乙烯转化率为93．3％，主产物苯甲醛的收率和选择性分别为66．8％和71．7％。     

酸功能化离子液体磺烷基咪唑磷酸盐催化合成乙酸松油酯的研究

制备、表征了酸功能化离子液体1-（3-磺酸）丙基-3-甲基咪唑磷酸二氢盐（（HSO，-pmim）H2PO4），并用于催化合成乙酸松油酯的反应研究，考察了反应时间、反应温度、原料配比、催化荆用量等因素对反应的影响。在松油醇5．1g、n（松油醇）：n（乙酸酐）1：1．5、离子液体1．5g、反应温度40℃、反应时间8h的工艺条件下，松油醇转化率为100％，乙酸松油酯的选择性为87．2％；并对离子液体（HSO3-pmim）H2PO4的重复使用性能进行了考察，离子液体在不经处理直接重复使用6次后，松油醇的转化率为99．4％，乙酸松油酯的选择性为88．6％，具有较好的重复使用性能。     

蓖麻油水性聚氨酯树脂的合成与性能的研究

采用蓖麻油(C．O．)、聚醚(N210)、二异氰酸甲苯酯(TDI)和二羟甲基丙酸(DMPA)反应合成了聚氨酯脲水分散液，研究了C．O．／N210的质量比、亲水单体含量、NCO／OH摩尔比和NH／NCO摩尔比对聚氨酯乳液及涂膜性能的影响，并应用傅立叶红外光谱仪(FT—IR)测定反应产物的结构。研究发现C．O．可提高水性聚氨酯涂膜的物理机械性能和耐水性，当C．O．／N210的质量比为1：1、NCO／OH摩尔比为1．6：1、DMPA添加量为5．5％、NH2／NCO摩尔比为0．50：1时合成的水性聚氨酯涂料具有较好的成膜性、较高的硬度、优异的附着力和较好的耐水、耐油性。     

松香酯乳液制备工艺研究

以松香为原料制备松香酯专用乳化剂SX-1．并探讨用其制备松香酯乳液的工艺．研究各种影响因素如乳化剂的用量、添加方式、离子型表面活性剂与助乳剂的选择、转相过程的操作条件等对乳液稳定性的影响．提出了合理的工艺条件。结果表明．用SX-1制备的松香甘油酯乳液稳定期超过6个月。     

细乳液聚合制备歧化松香-丙烯酸酯复合高分子乳液工艺的研究

通过细乳液聚合方法成功制备了歧化松香-丙烯酸酯复合高分子乳液。考察了聚合过程中水溶性引发剂用量、乳化剂用量、引发剂种类、歧化松香含量等对单体转化率和聚合物粒子粒径变化的影响。实验结果表明：引发剂或乳化剂的用量增加可以提高单体的转化速率量的增加降低了聚合速率，；引发剂水溶性的降低可以更好地控制聚合过程中的粒径变化；歧化松香含但对单体的最终转化率影响不大。力学性能分析显示歧化松香在杂合物中起到了增塑剂的作用，降低了聚合物的玻璃化转变温度，使得断裂应力下降而断裂伸长率有所增长。     

新型单组分家具组装胶的研制

将PVA水溶液、无机填料与高乙烯、高固体含量的VAE乳液复配，通过高速分散方式尽量增加填料的添加量，开发了一种高固体含量的家具组装胶。试验结果表明，当800目的重质碳酸钙与浓度为14％的聚乙烯醇水溶液质量比为1．6时，分散效果最佳；当VAE与填料质量比为1．6时，粘接强度最好。水性纳米膨润土用量占体系比例为10％时，对胶粘剂的固化速度和粘接强度影响最大。     

聚丙烯酸酯粘合剂

该产品是由多元丙烯酸酯类单体，经乳液共聚制得的水性高分子粘合剂。本技术采用先进的种子——核壳乳液聚合工艺，根据FOX方程和表面活性剂结构等科学原理设计配方。根据配方中单体的组成及合成工艺不同，产品又有软性、中性、硬性之分，也有自交联型和外交联型之分。可广泛用作涂料、纺织布处理、无纺布、静电植绒、皮革涂料、压敏带中的粘合剂，预计国内每年用量3万吨～5万吨、该技术在涂料和砂带方面的应用有两个成果已通过河南省科委和教委组织的专家鉴定。本产品的主要性能有：外观：白色略带兰荧光乳液；固含量：40％～46％．粘度…     

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.