小郁竹艺工艺及造型原则研究

小郁竹艺是湖南益阳地区历史悠久的民间传统手工艺技术,其手工制品不仅造型美观,而且做工精细、技艺精湛。自2006年"小郁竹艺"被列入非物质文化遗产以来,相继有很多学者对其进行了深入研究。笔者主要从小郁竹艺工艺技术的视角出发,以小郁竹艺结构特征为重点展开研究,旨在更好地保护和传承传统手工艺,同时为小郁竹艺的创新改良设计提供理论依据。     

用做家具与装饰材料竹材贴面杨木性能分析

杨木是我国主要的短周期工业用材林树种之一,但其材质松软,物理力学性能差,在家具与装饰利用方面受到很多限制。对20mm毛竹竹片进行含竹青、去竹青、染色、凹凸异形等表面处理后,采用热压工艺进行了竹片贴面速生毛白杨木材工艺试验,并探讨了竹片各种表面装饰处理的装饰效果和用途。结果表明：涂胶量120g/m^2,热压温度120℃,压力3MPa,热压时间5min,竹片与杨木基材胶合良好,既提高了杨木的物理力学性能,也提高了杨木的附加值扩大了应用范围。     

竹青砧板的研制开发

竹青为竹胶合板加工剩余物,由于表面有蜡质,不能被胶合,竹青的工业化应用尚为空白。作者对利用竹青开发生产竹青砧板的可行性、生产技术以及所产生的经济、社会、环境效益进行了分析,说明了竹青开发应用的可推广性。     

新型竹质复合板的研究(Ⅰ)

本文对利用小径级毛竹,采用不去竹青、竹黄的新工艺制造的竹-竹、竹-木复合胶合板作了研究,结果表明:对竹青、竹黄进行喷砂处理后而制成的竹胶板,具有非常高的强度。     

专利简介

专利简介新型竹地板系列该发明是以竹是以竹材为基材，以薄竹片、竹壳，竹片涂光涂料，竹叶、竹青经过处理粘贴在胶膜纸中为装饰材料。与基材一次复塑而成，实现了装饰整张化。其竹材利用率高，装饰效果好。（专利申请号：９５１０９４１３）木工四面刨机床该机床由活动平...     

竹青地板生产技术

竹青地板生产技术张德宣（四川宜宾大林工业开发试验区宜宾６４４０００）１竹青地板与众不同的特点近年来，各种天然竹地板、墙板等装饰板材相继问世。由于顺应了人们回归大自然的要求，已被越来越多的人所接受，市场前景是无容置疑的。但是，各种竹质装饰板均为平面板材...     

弧形竹片“剖黄联青”展开工艺研究

通过对竹片不同宽度、不同深度的展开,同时采用高温软塑处理和热压机双向热压的方法,对弧形竹片"剖黄联青"新工艺进行研究。结果表明:竹筒分片弧长越小,加工剩余物少,竹材利用率高;竹黄面纵向导向裂缝间距越小,则竹青面裂缝的开口越小,有利于竹筒的展开;高温软塑化处理后的竹材,储能模量比未软塑化处理竹材降低了60.4%,玻璃化转变温度下降了26.2%;运用此展开工艺制成的竹层积材的物理力学性能能够达到相关标准要求。     

竹材梯度结构对弯曲力学性能的影响

竹材梯度结构对力学性能影响显著,尤其是在弯曲应力下,更呈现明显的非对称行为。文章对竹材梯度结构进行详细解析,提取了维管束形状、纤维鞘面积、维管束梯度变化规律等多个梯度因子,然后对其弯曲力学性能进行测试,解析竹材梯度结构因子与弯曲力学性能之间的关系,阐明梯度结构对弯曲力学的影响机制。结果发现,毛竹维管束沿径向梯度分布的曲线属于下凹型曲线,梯度分布指数n=2.28;从竹青到竹黄,维管束长径比呈现明显下降的趋势,靠近竹青侧的维管束长径比较大,靠近竹黄侧的维管束长径比较小,形状更趋近于圆形;对比了竹黄侧加载和竹青侧加载2种模式下的竹材弯曲力学性能,当竹青侧受压、竹黄侧受拉的情况下,竹材的弯曲韧性最好;当竹青侧受拉、竹黄侧受压的情况下,竹材的弯曲模量最大。     

毛竹竹青片抗弯性能评价及分级

以毛竹竹青片为材料,测量试件的气干密度以及试件在径向加载(竹青面在上/竹青面在下)和弦向加载时的抗弯性能,分析气干密度和加载方式对其抗弯性能的影响。结果表明:竹青片的MOE和MOR与气干密度基本呈线性关系;加载方式不同,竹青片的抗弯力学性能差异显著。分别以竹青片的气干密度和弦向加载时的MOE为依据进行分级,并建立具体的分级指标。     

竹基纤维复合材料纤维化单板的形态研究

对梁山慈竹纤维化单板形态进行了研究。结果表明:节间竹青面和竹黄面、节部竹青面和竹黄面的平均裂隙角度为60°～70°;节间52%的竹青、节部75%的竹青发生脱落;节间竹束平均断面面积1.97mm2,包含4.61个维管束。节部竹束平均断面积1.83mm2,包含4.07个维管束。通过碾压疏解,对原竹进行可控分离,使复合材料制备达到广谱可设计性。     

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.