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林业局的木材检验科学管理是企业的重要管理手段,是提高木材价值的最好方法,运用科学的方法抓好林业局基层单位木材检验管理,能够为企业创造最大的经济效益。 相似文献
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谈如何做好原条合理造材 总被引：1，自引：0，他引：1
了解树木学、木材学、木材检验等方面的基础知识,掌握合理选材的基准,充分了解和掌握木材缺陷的分布与产生原因、蔓延程度及形成规律,进行准确地分析判断,是合理选材的基本前提。木材缺陷分10 相似文献
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强化木材检验管理,提高企业经济效益 总被引：3，自引：0，他引：3
木材检验工作是森工企业木材生产和经营过程中的重要环节,特别是改革大潮把企业抛向市场,企业的全部工作都纳入以提高经济效益为中心的轨道,木材检验工作就显得尤为重要,所以,必须强化对木材检验工作的管理。 相似文献
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加强贮木厂在木材检验中的科学管理 总被引：1，自引：0，他引：1
贮木厂的木材检验管理是林业企业的重要管理手段。抓好木材检验管理,既能有效地反映生产单位木材完成情况,又能指导林业局木材销售取向,提升单位木材价格,并且减少经济效益流失,为企业创造更大的经济效益和社会效益。 相似文献
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文章介绍了木材检验技术在木材运输中的作用与地位,分析了木材运输中常见的木材检验技术误区,阐述了由此引起的责任风险或者造成的危害,并依据现行木材检验标准规定,针对性地提出了规范的木材检验技术操作要领。 相似文献
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木材检验是木材贸易过程中的重要环节,木材检验标准或法规是评价木材材积和质量的重要依据。因采用不同木材检验的检测方法,各国在国际贸易中木材检验结果存在差异。文中对中国《原木检验》、俄罗斯《原木打号印、分类、运输、检量和验收方法》、美国《原木检尺和评等规则》和日本《原木等级和检尺规程》原木检验标准或法规进行比较,分析国内标准与国外标准在尺寸检验、材积计算和材质等级评定等方面的差异,以及不同检验方法间的相关性,以期为中国在进口原木贸易过程中标准制修订提供参考。 相似文献
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浅议《木材学》专题化教学北京林业大学李启岭《木材学》作为木材加工专业的一门专业基础课，主要讲述木材的构造与识别，木材化学、物理与力学性质，木材缺陷和木材改性等内容。根据现行的教学大纲要求，总学时为６０，其中课堂讲授为４０学时，实验为２０学时，课堂讲授... 相似文献
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The aim of this research was to test the hypothesis that exposure to solar radiation increases the checking of wood exposed
to the weather, and to examine the causes and spectral dependency of such an effect. Lodgepole pine decking samples were exposed
outdoors under filters, which blocked selected regions of the solar spectrum while allowing other weathering factors to act
on samples. Surface checking in samples was quantified after 12, 24 and 36 weeks of exposure, and the chemical and micro-structural
changes occurring at weathered wood surfaces were examined. Check numbers and dimensions were greater in samples exposed under
a filter to the full solar spectrum than in samples exposed under filters that blocked the transmission of UV, visible or
infrared radiation. Samples that were shielded from more energetic wavelengths developed less checking and also showed less
delignification at the exposed wood surfaces. Checks developed at the margins of rays and propagated at the interface between
adjacent tracheids, close to the middle lamella. We conclude that exposure to UV and visible light increases the tendency
of wood to check during exterior exposure. Our findings point to a link between changes in cell micro-structure as a result
of photodegradation of lignin and the development of visible checks in wood exposed outdoors. 相似文献
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木材碳学是近年来兴起的一门科学, 其主要研究内容包括木材碳素的储存量、木材储能、人工林木材固碳增汇与优质木材培育技术及木质产品固碳延伸等方面。文中简述了木材碳学研究中木材固碳量与含碳率、木材固碳量的影响因素、木材固碳量与木材热值的关系以及木质材料固碳量和固碳延伸等方面的研究现状, 并对今后的研究方向进行了展望。 相似文献
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Summary Fuels such as wood and forest residuals are becoming important sources of energy; furthermore, wood and wood products are major components of building construction. In both cases environmental impact and health hazard posed by the burning of these materials must be evaluated. Most death and injuries on exposure to burning wood are due to inhalation of toxic gases, smoke, and heat gases, usually carbon monoxide. Any wood or wood products used in building construction must be chosen so as to release the minimum amount of toxic materials as slowly as possible when heated or burned, to allow people time to escape. The emissions from wood burning power plants certainly have local short term and global long term environmental impacts. For example, massive carbon dioxide production from wood burning is believed to affect the earth's energy balance and therefore global climates. This review does not consider this aspect of wood burning, or other environmental hazards due to power plants utilizing wood, about which little seems to be known. The subject of this review is of the literature from 1971–1979 concerned with the toxicity of products of combustion and/or pyrolysis of wood, or wood products, untreated or treated with preservatives. 相似文献
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国内外木材工业态势和我国的可持续发展对策 总被引：1，自引：0，他引：1
鉴于木材资源的可于生性,木材及木材产品优良的应用和加工特性,木材工业对市场需求负有的责任及其与社会、经济、环境等可持续发展的相互依存性,木材工业的继续发展具有客观必然性。 相似文献
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Jarl-Gunnar Salin 《Wood material science & engineering》2006,1(2):45-51
A stochastic three-dimensional model for the behaviour of free water in wood, which was described in Part I, is used for the simulation and analysis of some further features of wood drying. The kiln brown stain mechanism is studied and the connection to the condition of the wood surface is pointed out. Several drying rate questions and related aspects are analysed and compared with experimental results. Finally the risk of surface checking in an early stage of sapwood drying is shown theoretically. 相似文献
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Kana Yamashita Yasuhiko Hirakawa Shuetsu Saito Hiroshi Nakatani Motoyoshi Ikeda Masamitsu Ohta 《Journal of Wood Science》2014,60(1):1-11
The effect of cross-sectional dimensions on bow and surface checking were investigated, using the boxed-heart square timber of two sugi cultivars with dimensions 80, 120, and 140 mm and length 1.9 m taken at two different heights above the ground. The smaller cross-sectional timber tended to have larger bow, less surface checking, and larger dimensional shrinkage. However, the drying defects were different between the cultivars and sampling heights, depending on the shrinkage properties of the juvenile wood and the heartwood proportion in the core part of the stem. The bow was larger in the smaller cross-sectional timber in which the longitudinal shrinkage was large in the juvenile wood. Surface checking was more prominent in larger cross-sectional timber containing sapwood in its outer part, which suggested the surface checking was induced by drying stress, owing to large moisture gradients between the heartwood and sapwood. The cross-dimensional shrinkage of the timber was larger in timber with larger tangential shrinkage. 相似文献
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《Wood material science & engineering》2013,8(2):45-51
Abstract A stochastic three-dimensional model for the behaviour of free water in wood, which was described in Part I, is used for the simulation and analysis of some further features of wood drying. The kiln brown stain mechanism is studied and the connection to the condition of the wood surface is pointed out. Several drying rate questions and related aspects are analysed and compared with experimental results. Finally the risk of surface checking in an early stage of sapwood drying is shown theoretically. 相似文献