共查询到20条相似文献，搜索用时 62 毫秒
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木棉(Gossampinus malabarica)又名攀枝花、红棉、英雄树、烽火树,属木棉科木棉属落叶高大乔木.木棉广泛分布在我国四川、云南、贵州、广西、广东,生长在江河沿岸、山地阳坡及村边道路旁,喜光、耐高温,对土壤要求不苛刻.在四川攀枝花地区木棉树于1月-2月份开花,先花后叶,花色艳丽,有红色、金黄、淡黄色等颜色,树形高大伟岸,是优良的园林绿化树种.木棉树现是攀枝花市市花和广州市市树,在园林绿化中常作行道树、庭荫树、景园树、盆景树等.木棉经嫁接后2 a-3 a开花,嫁接苗可作盆景矮化栽培,观赏价值高.本文介绍了木棉的嫁接育苗技术. 相似文献
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One compound approach combining factor-analytic model with AMMI and GGE biplot to improve multi-environment trials analysis 总被引：1，自引：0，他引：1
To improve multi-environmental trial(MET)analysis,a compound method—which combines factor analytic(FA)model with additive main effect and multiplicative interaction(AMMI)and genotype main effect plus genotype-by-environment interaction(GGE)biplot—was conducted in this study.The diameter at breast height of 36 open-pollinated(OP)families of Pinus taeda at six sites in South China was used as a raw dataset.The best linear unbiased prediction(BLUP)data of all individual trees in each site was obtained by fitting the spatial effects with the FA method from raw data.The raw data and BLUP data were analyzed and compared by using the AMMI and GGE biplot.BLUP results showed that the six sites were heterogeneous and spatial variation could be effectively fitted by spatial analysis with the FA method.AMMI analysis identified that two datasets had highly significant effects on the site,family,and their interactions,while BLUP data had a smaller residual error,but higher variation explaining ability and more credible stability than raw data.GGE biplot results revealed that raw data and BLUP data had different results in mega-environment delineation,test-environment evaluation,and genotype evaluation.In addition,BLUP data results were more reasonable due to the stronger analytical ability of the first two principal components.Our study suggests that the compound method combing the FA method with the AMMI and GGE biplot could improve the analysis result of MET data in Pinus teada as it was more reliable than direct AMMI and GGE biplot analysis on raw data. 相似文献
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近年来,绿色建筑成为国内乃至国际建筑界、房地产界的一个热点话题,绿色建筑的发展也越来越受到关注,许多国家都开展了绿色建筑的研究和实践,取得了很多的研究成果.尤其在去年经历了一场与"非典"的斗争之后,人类更加深刻地认识到绿色建筑在生活中的重要性,由此也引发了一场关于绿色建筑的革命,将绿色建筑向更深入、更科学的方向推进. 相似文献
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Natural spruce-fir mixed stand is one of the main forest types in the world,and also has huge ecological,economic and social benefits.According to the structural characteristics and succession laws of natural spruce-fir forest,it is urgent and significant to develop scientific management measures for natural spruce-fir mixed stand in line with local conditions.The article outlined the characteristics of the distribution and structure, regeneration and succession laws of natural spruce-fir forest,and analyzed the current situation and existing problems of natural spruce-fir forest management.The following recommendations were eventually made:1) In no cutting area,all logging activities should be banned.In a restricted cutting area,the cutting intensity should be generally controlled within 15%of the stock volume before cutting.On the commodity forest management area, the appropriate cutting intensity should be determined according to the volume per hectare,determine and classification management should be implemented in accordance with the characteristics of forest,to ensure the scientific selective cutting.2) Closure for afforestation,planting and repair planting should be adopted on vegetation-intensive land,sparse shrubs covered land and harvesting slash,in order to accelerate natural regeneration.3) The in situ conservation should be conducted in nature reserves and scientific experiment stations of rare and endangered species,such as Abies chensiensis,Picea neoveitchii,Abies vuanbaoshanensis,to reduce human destruction.4) It is supposed to collect seeds in time,establish nursery,actively establish forest, expand artificial population and promote natural regeneration. 相似文献
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《技术与市场》2007,(1):23
当前现代化的航天、航空、汽车、机械、电子、民用建筑、化工等行业迫切要求具备很高的力学性能及耐热、耐磨、耐化学性能的材料.因此高分子材料发展的一个重要方向就是通过对现有聚合物进行物理和化学改性,使其进一步高性能化、结构化、工程化.北京化工大学研制的聚氯乙烯合金是通过挤出机的力学、化学作用及接枝、复合技术使聚氯乙烯塑料工程化,成为物理性能可与ABS相比拟的新材料.聚氯乙烯合金具有高流动性、高韧性,完全可以代替ABS注塑计算机、电视机、冰箱、照相机、仪表等外壳.聚氯乙烯合金还具有良好的耐寒性,可制作各种规格的异型材,包括门窗、上水管道等.产品市场前景好,具有很强的竞争力,有很好的经济效益和社会效益. 相似文献
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对山茶属的14种植物的染色体进行了研究。根据核型分析结果,对山茶的亚属、组、之间的核型进行了比较分析,建议把茶、普洱茶,茶梨油茶和博白大果油茶划为独立的种。在核型描述和核型类型划分的理论方法上,引入了“臂比均值”这一参数,提出了“整齐性”和“整齐性系数”。并提出染色体数目的系列变异和结构变异是山茶属植物新种起源的两条途径。 相似文献
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优种核桃嫁接繁殖技术试验 总被引：3，自引：0，他引：3
培育优种核桃嫁接苗是实现核桃栽培良种化、集约化、基地化、商品化的根本途径。1999～2001年经过对辽宁1号、鲁光、中林3号、晋龙1号等优种核桃嫁接苗繁殖试验,总结出适合当地的核桃嫁接苗繁殖技术,成活率最高达到98%。 相似文献
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针叶树木材细胞力学及纵向弹性模量的计算--试件纵向弹性模量的预测 总被引：3，自引：1，他引：3
依据针叶树木材管胞和射线细胞的结构模型。使用计算机抽样模拟解剖结构参数。以及使用针叶树木材纵向弹性模量计算公式和方法,计算人工林杉木,马尾松幼龄材和成熟材试件纵向弹性模量,计算结果与常温条件下气干试件测定结果十分符合。在试件晚材率和管胞解剖结构参数改变的条件下。计算预测了人工林杉木,马尾松幼龄材和成熟材纵向弹性模量的变化。结果表明：试件纵向弹性模量随晚材率,管胞长度,管胞壁厚度的增加而增加,而试件纵向弹性模量随管胞直径增加而减小。本文提出的纵向弹性模量计算的预测方法,对于运用现代生物技术控制和改变针叶树木材的材质,材性有实际意义。 相似文献
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采用厚环乳牛肝菌,赭丝膜菌,灰环乳牛肝菌和彩色豆马勃４种外生菌根真菌固体纯培养接种物,对日本落叶松进行了圃地育苗接种试验。结果表明,苗高,地径,侧根数分别比较对照提高了１３．３８％－２３．５４％、１０．６５％－２４．７１％、９．９７％、－１３．７８％,苗木Ｎ、Ｐ、Ｋ含量分别比对照增加了０．７０％－１９．９６％、９．０６％－４７．８１％和１４．４５％－２１．１２％,苗木菌根感染率为６７．８２％－８３ 相似文献
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超声波处理对麦草碱木质素结构特性的影响 总被引：1，自引：0，他引：1
采用超声波作用于麦草碱木质素，探讨了超声波对碱木质素的活化作用，用化学法对超声波作用前后碱木质素官能团进行了定量测定，用凝胶色谱（GPC）测定了木质素相对分子质量的变化，用^1H NMR光谱对化学结构进行了分析。结果表明：超声波可以显著提高碱木质素酚羟基和醇羟基含量，当作用时间20min、作用功率200w、液料质量比100：1时，醇羟基含量从1．99mmol／g上升为4．14mmol／g，酚羟基含量从1．88mmol／g上升为2．54mmol／g，羧基含量从0．59mmol／g下降为0．29mmol／g，羰基含量从2．16mmol／g上升为2．68mmol／g。^1H NMR分析表明，愈创木基和紫丁香基峰面积与总峰面积的比值分别从3．61％和0．77％下降为0，甲氧基峰面积与总峰面积的比值从11．50％下降为8．90％。数均分子质量（Mn）和重均分子质量（Mw）分别从1179和10250上升为5031和11605，分散度（Mw／Mn）从8．69下降为2．31． 相似文献
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