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| 1 | Recognition of wood surface defects with near infrared spectroscopy and machine vision显示文摘To improve the accuracy in recognizing defects on wood surfaces,a method fusing near infrared spectroscopy(NIR)and machine vision was examined.Larix gmelinii was selected as the raw material,and the experiments focused on the ability of the model to sort defects into four types:live knots,dead knots,pinholes,and cracks.Sample images were taken using an industrial camera,and a morphological algorithm was applied to locate the position of the defects.A portable near infrared spectrometer(900–1800 nm)collected the spectra of these positions.In addition,principal component analysis was utilized on these variables from spectral information and principal component vectors were extracted as the inputs of the model.The results show that a back propagation neural network model exhibited better discrimination accuracy of 92.7%for the training set and 92.0%for the test set.The research reveals that the NIR fusing machine vision is a feasible tool for detecting defects on board surfaces. | Huiling Yu Yuliang Liang Hao Liang Yizhuo Zhang | 2019 | Journal of Forestry Research2019，30，6： | 16 |
| 2 | An improved binarization algorithm of wood image defect segmentation based on non-uniform background显示文摘In this study,an image binarization optimization algorithm,based on local threshold algorithms,is proposed because global and traditional local threshold segmentation algorithms cannot effectively address the problems of nonuniform backgrounds of wood defect images.The proposed algorithm calculates the threshold by the mean,standard deviation and the extreme value of the window.The results indicate that this modified algorithm enhances the image segmentation for wood defect images on a complex background,which is much superior to the global threshold algorithm and the Bernsen algorithm,and slightly better than the Niblack algorithm and Sauvola algorithm.Compared with similar models,the algorithm proposed in this paper has higher segmentation accuracy,as high as 92.6%for wood defect images with a complex background. | Wei Luo Liping Sun | 2019 | Journal of Forestry Research2019，30，4： | 13 |
| 3 | Wood模型和多元线性回归对奶牛个体泌乳曲线的拟合、预测及分析显示文摘本文利用Wood模型对北京黑白花奶牛的427个泌乳期逐个进行了拟合。拟合过程中采用最小二乘法估计了参数a、b、c,并进行了均方差RMS和拟合度R^2的计算。 | 储明星 张卫东 阚远征 师守堃 孙玉萍 邵西敏 刘忠贤 | 1991 | 中国奶牛1991，0，2： | 10 |
| 4 | Variation analyses of growth and wood properties of Larix olgensis clones in China显示文摘The growth traits(tree height, diameter at breast height, and stem straightness degree) and wood properties[wood density(WD), fiber length, fiber width, ash content(AC), lignin content, cellulose content, hemicellulose content(HEC), and holocellulose content] of 208 26-yearold Larix olgensis clones were analyzed. Except for WD and AC, there were significant differences(p \ 0.01) for all traits among clones. The phenotypic coefficient of variation and repeatability of all traits were 9.34–35.33%and 0.218–0.930, respectively. Tree height and diameter at breast height showed significant positive correlation;however, the correlation coefficients among growth characteristics and wood properties were mostly not significant.Ten clones(L70, L56, L82, L90, L59, L91, L61, L92, L86,and L64) were selected as excellent clones under a selection rate of 5%, using tree height, diameter at breast height,and stem straightness degree as evaluation indexes, providing genetic gains of 28.69, 17.96, and 0.67%, respectively. Ten clones(L88, L305, L59, L66, L253, L304,L277, L298, L248, and L293) were selected as excellent clones using wood properties as an evaluation index, with a selection rate of 5%, providing genetic gains in WD, fiber length, fiber width, cellulose content, and HEC of 4.14,3.64, 9.28, 6.77, and 9.61%, respectively. This study provides a theoretical basis for selecting excellent L. olgensis clones. | Shaopeng Yin Zhenhai Xiao Guohui Zhao Xin Zhao Xiaoyang Sun Ying Zhang Fuwei Wang Shuchun Li Xiyang Zhao Guan-Zheng Qu | 2017 | Journal of Forestry Research2017，28，4： | 6 |
| 5 | Wood/Cu复合材料的温压成形与表征显示文摘应用木材科学与技术、粉末冶金等交叉学科材料成形理论开发的木质粉末温压成形新技术,以芦苇秆(简称Wood)粉末为基材,在不添加任何可能造成环境污染的胶粘剂的前提下,制备的Wood/Cu复合材料的静曲强度、内结合强度分别高达85.55MPa、6.75MPa,磨耗量≤0.05g/100r、吸水率<0.50%,且具有韧性断裂特征;采用Wood/Cu复合材料制备的滑动轴承的压溃强度、表观硬度分别高达100MPa、50HB,可望用于替代粉末冶金烧结青铜生产轻载滑动轴承,从而在节约有色金属的同时,为农林木质剩余物的高质清洁利用开辟一条新途径。 | 吴庆定 张红 梁盛 | 2013 | 粉末冶金技术2013，31，6： | 5 |
| 6 | Characterization of Five Kinds of Wood Vinegar Obtained from Agricultural and Forestry Wastes and Identification of Major Antioxidants in Wood Vinegar显示文摘Wood vinegar(WV)has a powerful antioxidant activity,but it is unclear which components are responsible for the antioxidant activity.In the present study,the double-column retention index qualitative method was used for the identification of the major components in five kinds of W7 And the major antioxidants of wood vinegar were accurately identified with the aid of Pearson product-moment correlation coefficients and authentic standard samples. Our results demonstrate that phenolic compounds are mainly responsible for the powerful antioxidant activity. 2,6-Dimethoxyphenol is the most powerful antioxidant in WV.2-Methoxyphenol and 3-methyl-1,2-cyclopentanedioue also have an important influence on the antioxidant activity of WV.Our results suggest that the contents of 2-methoxyphenol,2,6-dimethoxyphenol and 3-methyl-1,2-cyclopentanedione should act as the criteria for evaluating the antioxidant activity of WV.Our work will provide useful information for WV's application in the fields of food and medicine as antioxidants. | LI Zhanchao ZHANG Zhiquan WU Lijie ZHANG Hanqi WANG Ziming | 2019 | Chemical Research in Chinese Universities2019，35，1： | 4 |
| 7 | Characteristics of typhoon disturbed gaps in an old-growth tropical montane rainforest in Hainan Island, China显示文摘Disturbances that create gaps can shape the structure and function of forests. However, such disturbance regimes in Asian tropical montane rainforests remain largely unquantified. Least studied are typhoon disturbances that are attributable to climate change. We investigated gap characteristics in terms of size, age, and gapmaker to quantify the gap disturbance regimes in an intact old-growth tropical montane rainforest on Hainan Island,China. The intensity of typhoons has increased since 1949,and typhoon winds blow mostly(45.5%) from the northeast corner of Hainan Island, resulting in a higher frequency of gaps in the northeast. A total of 221 gap-makers(trees that fell to create canopy gaps) and 53 gaps were observed in a 3.16 ha old-growth rainforest. Most canopy gaps(85%)were <200 m^2. The average size of canopy gaps was smaller in the rainforest than in other tropical forests, while the average size of expanded gaps was similar to those in other tropical forests. The maximum age of gaps was 23.5 years indicating that gaps had more rapid turnover than other parts of tropical forests. The frequency distribution of gap-makers followed a lognormal distribution with a distinctive peak at three gap-makers, which was different from the inverse J-shaped curve typical of other tropical forests. Gaps were recorded mainly on slopes between 20° and 35° and wood density of gap-makers was between 0.6 and 0.7 g cm^(-3). Our results suggest that small-scale disturbance was the dominant agent of gap formation in this old-growth rainforest that is subject to increasing typhoon disturbances. | Huai Yang Shirong Liu Kunfang Cao Jingxin Wang Yide Li Han Xu | 2017 | Journal of Forestry Research2017，28，6： | 3 |
| 8 | Low carbon storage of woody debris in a karst forest in southwestern China显示文摘The properties of woody debris(WD) vary across different forests under various soil conditions.Owing to the relatively shallow and low amounts of soils on karst terrains, it is necessary to determine the WD carbon inventory of karst forests. In this study, we recorded WD with a basal diameter for standing snags and the largeend diameter for fallen logs of ≥ 1 cm. The carbon density of WD in a secondary karst mixed evergreen and deciduous broad-leaved forest that had been clear-cut 55 years ago in southwestern China were inventoried in a 2 ha plot. Woody debris carbon density calculated using specific gravity and carbon concentration was 4.07 Mg C ha^-1. Woody debris with diameters ≥ 10 cm(coarse WD) constituted 53.8% of total carbon storage whereas WD < 10 cm in diameters(fine WD) accounted for more pieces of WD(89.9%).Lithocarpus confinis contributed the most WD carbon(26.5%). Intermediate decayed WD was relatively more abundant, but WD with final decay contributed the least to the total pieces of WD(6.7%). The contribution of WD to carbon storage of karst forest was low compared to other forests worldwide. Significant positive correlations were found between WD carbon and biodiversity(R^2= 0.035,p < 0.01) and elevation(R^2= 0.047, p < 0.01) and negative correlations was found in outcrop coverage(R^2= 0.034, p <0.01). Further studies are needed to elucidate the ecological functions of WD to better understand their roles in maintaining biodiversity, enhancing productivity, and controlling vegetation degradation in karst forest ecosystems. | Yangyang Wu Libin Liu Chunzi Guo Zhonghua Zhang Gang Hu Jian Ni | 2019 | Acta Geochimica2019，38，4： | 3 |
| 9 | THE EFFECT OF HEAT TREATMENT ON DIFFERENT SPECIES WOOD COLOUR显示文摘In this paper, the heat tratment of wood samples of 8 tree species with different colour were made at different temperature and time. Using SC-1 Model colorimeter, the colorimetric parameter was measured at quantitative measuring for treatment fore-and-after wood sampIes color. The effect of heat treatment conditions on wood color was analyzed. The results indicated: the temperature and time of heat treatment affected on big extent for wood samples color, in which the heat temperature was more evident than others. The luminance index of wood color parameter was more sensitive to treatment condition, which it reduced with temperature and time increasing, this kind of variation tendency was the same as all wood samples, but the variations extent was more different among the different wood species. After heat treatment the wood color hue and saturation variation direction were different for different wood species.This phenomenon had the relation to the migration and volatilization of color extract in heating process, or the rapid oxidation of lignin and some chemical element in high temperature. | 刘一星 李坚 王金满 严劲松 马彦华 | 1994 | Journal of Northeast Forestry University1994，5，4： | 3 |
| 10 | Wood density and carbon concentration of coarse woody debris in native forests,Brazil显示文摘Background: With the objective of increasing knowledge on biomass and carbon stocks, and thus improving the accuracy of published estimates, the present study explored wood density and carbon concentration of coarse woody debris (diameter≥10) by decay class in a Seasonal Semi-deciduous Forest (SSF) area in the Atlantic Rain Forest and in a Cerrado sensu-stricto (CSS) area (Brazilian savanna), in Brazil. Two strata were identified in each area and ten sampling units were systematic located in each stratum. Data were collected according to the line intersect sampling method. Each tallied element, the diameter, length, and perpendicular width were recorded at the transect intersection point. Each element was classified into a decay class, and the species was identified when possible. Sample discs were cut from each element, from which cylindrical samples were extracted and oven-dried to determine density. These cylinders were milled and analyzed using a LECO-C632 to determine carbon concentration as percentage of mass. Results: In both areas, wood density decreased as the decay class increased. For SSF the mean carbon concentration of all analyzed samples was 49.8% with a standard deviation of 3.3, with a range of 27.9–57.0% across 506 observations. For CSS the general mean was 49.6% with a standard deviation of 2.6, with a range of 31.2–54.5% over 182 observations. Carbon concentration barely change between decay classes. Carbon stock was estimated at 3.3 and 0.7 MgC/ha for the SSF and the CSS, respectively. Similar results were obtained when using a 50% conversion constant. Conclusions: The present study concludes that wood density decreases as the woody debris becomes more decomposed, a pattern found in many previous studies. The carbon concentration, however, barely changes between decay classes, and that result is consistent with most of the literature reviewed. Our carbon concentrations are very close to the 50% used most commonly as a conversion factor. We strongly recommend that future studies of CWD evaluate wood density and carbon concentration by decay class to address the uncertainty still found in the literature. | Andrea B.Moreira Timothy G.Gregoire Hilton Thadeu Z.do Couto | 2019 | Forest Ecosystems2019，6，2： | 3 |
| 11 | 从加拿大18层木结构公寓项目看装配式建筑创新显示文摘加拿大作为可持续林业资源的大国,有着先进的木结构建筑技术以及完善的产业配套,发展装配式是木结构建筑的路径选择,其中的经验值得我们借鉴。文章叙述了加拿大可持续林业资源管理和木结构建筑行业技术的发展现状,并以在建时全球最高18层木结构大楼Brock Commons为例,从政策机制、技术体系、管理模式、施工组织几个方面,探讨了木结构建筑与装配式建筑的创新。最后结合国内发展现状,对木结构建筑的性能展开分析,包括建筑装配率评价等级、地震灾害地区适用性、绿色环保可再生、耐久性和宜居性。 | 忻剑春 陶亮 张娟 | 2018 | 住宅产业2018，0，11： | 3 |
| 12 | Thermal characterization of bio-based phase changing materials in decorative wood-based panels for thermal energy storage显示文摘Decorative wood panels containing pouches of bio-based phase changing materials(PCMs) were prepared. Three different PCM mixtures were used: a blend of capric and lauric acids as well as two commercial products, Puretemp?20 and Puretemp?23(Puretemp). The panels consist of engraved Medium Density Fiberboard(MDF) filled with a plastic pouch filled with PCM. High density fiberboard(HDF) was used on top of the panels to enclose the PCM pouches. PCM mixtures were first tested by differential scanning calorimetry(DSC). Phase change temperature and total heat storage of the panels were measured for both fusion and solidification with a Dynamic Heat-Flow Meter Apparatus(DHFMA). DSC and DHFMA results were compared, allowing a better understanding of results gathered from these two techniques. DSC calibration has been revealed important when assessing PCMs. The panels present a phase change temperature and a latent heat storage suitable for buildings applications. The panel made with Puretemp?23 presented the highest energy, with 57.1 J g^(-1). Thermal cycling was conducted on the panels to investigate thermal reliability, which revealed small modifications of thermal properties for two products. For all cases, latent heat was found stable. Hygro-mechanical behavior of the panels was also evaluated as these where designed to be esthetic decorative panels. This study exposes the potential of a new type of wood-based panels loaded with PCM for thermal energy storage and brings overall knowledge about PCM products thermal characterization. | Damien Mathis Pierre Blanchet Véronic Landry Philippe Lagière | 2019 | Green Energy & Environment2019，4，1： | 2 |
| 13 | Determination of coefficients of friction for laminated veneer lumber on steel under high pressure loads显示文摘In this study,static coefficients of friction for laminated veneer lumber on steel surfaces were determined experimentally.The focus was on the frictional behaviors at different pressure levels,which were studied in combination with other influencing parameters:fiber orientation,moisture content,and surface roughness.Coefficients of friction were obtained as 0.10–0.30 for a smooth steel surface and as high as 0.80 for a rough steel surface.Pressure influenced the measured coefficients of friction,and lower normal pressures yielded higher coefficients.The influence of fiber angle was observed to be moderate,although clearly detectable,thereby resulting in a higher coefficient of friction when sliding perpendicular rather than parallel to the grain.Moist specimens contained higher coefficients of friction than oven-dry specimens.The results provide realistic values for practical applications,particularly for use as input parameters of numerical simulations where the role of friction is often wrongfully considered. | Michael DORN Karolína HABROVÁ Radek KOUBEK Erik SERRANO | 2021 | Friction2021，9，2： | 2 |
| 14 | Research advance in wood composites in China显示文摘Wood composites can generally be classified in three parts:laminated composites, mixed composites and penetrated composites, Every part has its own characteristic and can be further divided. This paper introduces the history and the state of development of wood composites in China. The research about glue-laminatedtimber is rare and the industry hardly comes to being, A great of achievements have been obtained in mixed cosmosites and it is well industrialized, Many studies on scrimber have been done and the Chinese researchers arelooking for a feasible way to develop the scrimber industry in China, Chinese researchers also spent so much en ergy in studying wood plastic composites (WPC), but it has not been industrialized due to the high | 李淑君 李坚 | 1999 | Journal of Forestry Research1999，10，3： | 2 |
| 15 | Studies on inner wall structure of tracheids in Taxus chinensis with resin casting method显示文摘The resin casting method has been applied to studying the inner wall structure of tracheids in normal and compression wood, Taxus chinensis in gymnosperm. Not only the structures which are visible by the conventional method, but also the three-dimensional structures of pits pair in intertracheids unvisualized by the normal way have been observed. Moreover, it is found that there exist many differences in the angle, trend and occurrence of helical thickenings and distribution of warty layers on the inner walls of tracheids in normal and compression wood. | Jianhua Xu Yuxi Hu Jinxing Lin | 1999 | Chinese Science Bulletin1999，44，15： | 2 |
| 16 | Impact of exclosures on wood biomass production and fuelwood supply in northern Ethiopia显示文摘In the Ethiopian highlands, communal grazing lands are one of the major land uses, and are source of livelihood for the rural people. Free and uncontrolled grazing in the communal grazing lands is the dominant grazing system. The traditional uncontrolled and free grazing system has caused severe degradation of the grazing lands. As a result, communities have started to establish exclosures and support the restoration of degraded communal grazing lands. Studies have shown that exclosures are effective to restoring degraded communal grazing lands and improving ecosystem services. However, studies that investigate the changes in aboveground biomass following the establishment of exclosures and compare it with fuelwood demand of the beneficiaries in our study area is lacking. Therefore, our study aimed at:(1) quantifying yearly biomass accumulation in exclosures and compare it to fuelwood demand of households that manage the exclosures;(2) assessing household energy sources and their consumption levels. To monitor changes in biomass production with over time, replicated(n = 3) 5 and10 year-old exclosures were sampled. To investigate fuelwood sources and consumption patterns, household surveys, key informant interviews and focus group discussion were conducted. Our results demonstrated that total biomass production increased with exclosure age. In both exclosure, biomass production from Vachellia etbaica was significantly(p \ 0.05) greater than that from Euclea.racemosa. Average daily fuelwood consumption per person was(0.63 ± 0.2) kg day^(-1). This means that the total biomass(27.5 Mg year^(-1)) obtained from 114.6 ha of exclosures covers only 9.4% of yearly fuelwood demand of the residents who manage the sampled exclosures. Nearly all respondents(95%) confirmed that they travel more than10 km day^(-1) to gather fuelwood from surrounding degraded forest patches. We recommend plantings of fast growing native tree species within exclosures and around homesteads to provide a sustainable fuelwood supply and using improved stoves to address the problem of fuelwood shortage. District agricultural offices could provide seedlings of native plant species, while communities provide unpaid labour for planting and managing plantations. | Wolde Mekuria Mastewal Yami Mitiku Haile Kindeya Gebrehiwot Emiru Birhane | 2019 | Journal of Forestry Research2019，30，2： | 2 |
| 17 | Brief report on theoretical research upon wood thermal property显示文摘In this paper, the theoretical expressions of the specific heat and thermal conductivity of wood are first derived from the micro-Structure of wood by applying some basic principles in statistical thermodynamics and physical mechanics. Tested by a great rnany experiments, the average error of theoretical values is about 5%,much less than that of all kinds of exiting empiric equations in the world. | 杨庆贤 张春英 | 2000 | Journal of Forestry Research2000，11，2： | 2 |
| 18 | Biomass production and carbon balance in two hybrid poplar(Populus euramericana)plantations raised with and without agriculture in southern France显示文摘Poplar is useful in different climates for bioenergy production and carbon sequestration when planted as a single species or in agroforestry. Europe has large areas potentially suitable for poplar forestry and a bioenergy policy that would encourage poplar forestry. In this study I estimated biomass production and carbon sequestration in poplar monoculture plantation and poplar-wheat agroforestry, in the Mediterranean region of France. A single-tree harvesting method was used to estimate biomass and an empirical conversion factor was adopted to calculate sequestered carbon. Total biomass was higher in agroforestry trees(1223 kg tree^(-1)) than in monoculture plantation trees(1102 kg tree^(-1)).Aboveground and belowground biomass distributions were similar in both cases(89 and 88% aboveground, and 11 and12% belowground, respectively in agroforestry and monoculture). The partitioning of total biomass in an agroforestry tree in leaves, branch, and trunk(aboveground), and fine roots, medium roots, coarse roots and underground stem(belowground) was 1,22,and 77,and 6,9, 44 and 40%,respectively. Except for branch and trunk, all other compartments were similarly distributed in a monoculture tree.Storage of C was higher in agroforestry trees(612 kg tree^(-1))than in monoculture trees(512 kg tree^(-1)). In contrast, C storage on a per hectare basis was lower in agroforestry(85 Mg ha^(-1)) than in monoculture(105 Mg ha^(-1)) due to the lower density of trees per hectare in agroforestry(139 trees in agroforestry vs 204 trees in monoculture). On a per hectare basis, soil C stocks pattern were similar to per tree stocking:They were higher in agroforestry at 330 Mg ha^(-1) than in monoculture 304 Mg ha^(-1). Higher C accumulation by agroforestry has a direct management implication in the sense that expanding agroforestry into agriculture production areas with short rotation and fast growing trees like poplar would encourage quicker and greater C sequestration. This could simultaneously fulfil the requirement of bioenergy plantation in Europe. | Kaushalendra Kumar Jha | 2018 | Journal of Forestry Research2018，29，6： | 2 |
| 19 | Comparative tree-ring anatomy of Fraxinus excelsior with Chalara dieback显示文摘We tested the hypothesis that the biometrical characters of wood elements in ash trees(Fraxinus excelsior L.) become modified in response to the progression of disease caused by Chalara fraxinea. Anatomical analyses were performed on wood samples collected at breast height from the trunks of groups of ash trees which contained healthy, weakened and dead trees. We measured(1) treering width,(2) earlywood vessel diameter,(3) earlywood vessel element length,(4) fibre length,(5) fibre diameter,(6) fibre lumen diameter, and(7) fibre wall thickness. We showed that tree-ring width diminished in all analysed groups during disease progression. However, the greatest suppression of growth was observed in dead trees. In both weakened and dead ash trees, the reduction in tree-ring width was accompanied by diminished vessel diameter in the earlywood of the outermost annual rings. The annual rings of dead trees had shorter fibres having greater lumen diameter and thinner cell walls. Consequently, water conduction in the sapwood of dead ash trees was less efficient owing to reduced vessel diameter, and this seems to be one of the greatest disease-induced morphological modifications. All the anatomical modifications might be due to leaf loss and crown dieback triggered by Chalara fraxinea. | Mirela Tulik Barbaros Yaman Nesibe Kose | 2018 | Journal of Forestry Research2018，29，6： | 1 |
| 20 | Study on the specific heat of wood by statistical mechanics显示文摘From the microstructure of wood, theoretical expressions of the wood specific heat were derived by statistical mechanics. With the theoretical expressions derived, the theoretical values of specific heat for 33 tree species, with different moisture contents and under varied temperature conditions were calculated and comparison was also made to the experimental values under the same conditions. The results showed that the maximum error and mean error by the theoretical expressions of this paper are only 7.8% and 2.5% respectively, while those error of the theoretical values for 33 tree species calculated with Dunlap’s empiric equation were 15.2% (max.) and 9.3% (mean), and forКириллов empiric equation, they were 20% (max.) and 11% (mean). | 杨庆贤 | 2000 | Journal of Forestry Research2000，11，4： | 1 |
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