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Journal of Environmental Sciences 2024年第4期138卷 266-276页

作者： Xu Liu Xun Wang Dingyong Wang College of Resources and Environment Southwest UniversityChongqing 400715China State Key Laboratory of Environmental Geochemistry Institute of GeochemistryChinese Academy of SciencesGuiyang 550081China

The tree ring has been regarded as an emerging archive to reconstruct historical atmospheric mercury(Hg)trends,but with the large knowledge gaps in the *** this study,we comprehensively evaluated the Hg source,radial translocation and age effect of masson pine(Pinus massoniana)tree ring at *** in Chongqing,to assess the suitability of such tree ring as the archive of atmospheric *** showed that distinct variabilities among masson pine tree-ring Hg concentration *** Hg concentration significantly increased along with stem height(P<0.05),indicating the Hg in tree rings mainly derived from foliage uptake atmospheric *** found a distinct age effect that the tree ring of young trees had the higher Hg ***,we used the advection-diffusion model to demonstrate how Hg concentration shifted by the advection or/and diffusion in tree *** modeling results showed that the advection induced radial translocation during the young growth period of tree was a plausible mechanism to result in the tree-ring Hg record largely different from the trend of anthropogenic Hg emissions in *** finally suggest that in further Hg dendrochemistry,better discarding the tree-ring Hg profile of the young growth period to reduce impacts of the radial translocation and age effect.

关键词： masson pine Tree-ring mercury Radial translocation Tree age effect

Nail Holding Performance of Self-Tapping Screws on masson pine and Chinese Fir Dimension Lumbers

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Journal of Renewable Materials 2023年第10期11卷 3725-3738页

作者： De Li Bengang Zhang Yuan Tu Guoming Xiao Meifen Tian Xiaoxue Xu Xiao Zhong Qiaoyan Zhang Zhigang Wu Jiankun Liang College of Forestry Guizhou UniversityGuiyang550025China Forestry Science and Technology Promotion Station Xifeng County Bureau of Natural ResourcesGuiyang551100China Forest Park Management Section Zhazuo State-Owned Forest FarmGuiyang550299China College of Civil Engineering Kaili UniversityQiandongnan556011China

Screw connection is a type most commonly applied to timber *** important commercial tree species in China,masson pine and Chinese fir have the potential to prepare wood *** this study,the effects of the diameter of the self-tapping screw and the guiding bores on the nail holding performance on different sections of masson pine and Chinese fir dimension lumbers were mainly *** results showed that:(1)The nail holding strength of the tangential section was the maximum,followed by that of the radial section,and that of the cross section was the minimum.(2)The nail holding strength of masson pine was higher than that of Chinese fir.(3)The nail holding strength grew with the increase in the diameter of self-tapping screws,but a large diameter would lead to plastic cracking of the timber,thus further affecting the nail holding *** pine and Chinese fir reached the maximum nail holding strength when the diameter of self-tapping screws was 3.5 mm.(4)Under a large diameter of screws,prefabricated guiding bores could mitigate timber cracking and improve its nail holding strength.(5)Prefabricated guiding bores were more necessary for the screw connection of masson *** results obtained could provide a scientific basis for the screw connection design of masson pine and Chinese fir timber structures.

关键词： masson pine Chinese fir self-tapping screws nail holding performance

Preparation and Properties of HBS Lignin from masson pine

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Chemical Research in Chinese Universities 2004年第2期20卷 225-228页

作者： CHENGXian-su CHENWei-jian CHENYun-ping CHENYue-xian LIMian-jun FANGHua-shu CollegeofMaterialScienceandEngineering FuzhouUniversityFuzhou350002P.R.China DepartmentofChemistryandChemicalEngineering MinjiangUniversityFuzhou350011P.R.China

In order to establish a new method for making cellulose and lignin from masson pine, a high boiling solvent(HBS) pulping process with an aqueous solvent of 1,4-butanediol was investigated. masson pine chips were pulped with a 70%—90% aqueous solution of 1,4-butanediol containing a small amount of a catalyst at 200—220 ℃ for 60—180 min. HBS masson pine cellulose is suitable for making paper. Water-insoluble HBS lignin was separated from the liquor reaction mixture by water precipitation. The recovered high boiling solvent(RHBS) is able to be recycled as a pulping solvent, indicating that the HBS method is a pulping process of masson pine which is energy saving, resources saving and pollution free. HBS lignin has a better chemical reactivity and a lower ash content than lignin sulfonate.

关键词： High boiling solvent(HBS) masson pine Lignin 1,4-Butanediol

Microfibril angle variability in masson pine (Pinus massoniana Lamb.) using X-ray diffraction

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Forestry Studies in China 2007年第1期9卷 33-38页

作者： Zhang Bo Fei Ben-hua Yu Yan Zhao Rong-jun Research Institute of Wood Industry Chinese Academy of Forestry Beijing 100091 E R. China International Center for Bamboo and Rattan Beijing 100102 P. R. China

The microfibril angle of fiber walls is an ultra-mieroscopic feature affecting the performance of wood products. It is therefore essential to get more definitive information to improve selection and utilization. X-ray diffraction is a rapid method for measuring microfibril angles. In this paper, the variability of microfibril angle in plantation-grown masson pine was investigated by peak-fitting method. This method was compared with the traditional hand-drawn method, 40% peak height method and half peak height method. X-ray diffraction measurements indicated that the microfibril angle changed as a function of the position in the tree. The mean microfibril angle decreased more gradually as the distance increased from the pith and reached the same level in mature wood. The microfibril angle also seemed to decrease clearly from the base upward. Differences of angle-intensity curves between heartwood and sapwood were also examined.

关键词： X-ray diffraction microfibril angle peak-fitting method half peak height method masson pine

Studies on Electrolyte Conductivity and Activity of Dehydrogenase of Chinese Fir and masson pine Bare-Root Seedling under Water and Cold Stress

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Forestry Studies in China 2003年第1期5卷 30-33页

作者： YuFangyuan XuXizeng GuoXinbao CollegeofForestResoureesandEnivironment NanjingForestryUniversityNanjing210037P.R.China HangzhouForestryandWaterConservancyBureau Hangzhou310016P.R.China

The electrolyte conductivity and activity of dehydrogenase of bare-root seedlings of both Chinese fir (Cunningha-mia lanceolata (Lamb.) Hook.) and masson pine (Pinus massoniana Lamb.) under freezing and desiccation treatments were studied. The results showed that needle electrolyte conductivity of both species increase significantly after freezing treatment and there are no significant differences in needle electrolyte conductivity between the two species. The dehydrogenase activity (ARD) of fine roots of both Chinese fir and masson pine was negatively correlated with increasing freezing and desiccation. The results suggest that both electrolyte conductivity and dehydrogenase activity could be used as quick indicators of Chinese fir and masson pine bare-root seedling quality.

关键词： electrolyte conductivity activity of dehydrogenase (ARD) Chinese fir masson pine seedling quality

派阳山林场从事业型林场向企业型林场转变的调查

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中国农村经济 1995年第7期 54-56页

作者：李甫春韦尊达秦崇彪广西国营派阳山林场广西社会科学院

派阳山林场从事业型林场向企业型林场转变的调查李甫春，韦尊达，秦崇彪长期在计划经济体制下专司营林的国家林场，如何向社会主义市场经济体制转轨，从按计划营林向按市场需求经营过渡，从事业型林场向企业型林场转变，最终按市场经济... 详细信息

派阳山林场从事业型林场向企业型林场转变的调查李甫春，韦尊达，秦崇彪长期在计划经济体制下专司营林的国家林场，如何向社会主义市场经济体制转轨，从按计划营林向按市场需求经营过渡，从事业型林场向企业型林场转变，最终按市场经济体制运转？广西国营派阳山林场经过几...

关键词： masson pine Branchwood Compression wood Opposite wood Chemical properties Physical and mechanical properties

Physiological responses of needles of Pinus massoniana elite families to phosphorus stress in acid soil

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Journal of Forestry Research 2013年第2期24卷 325-332页

作者： HE You-lan LIU Ai-qin Mulualem Tigabu WU Pengfei MA Xiang-qing WANG Chen Per Christer Oden Forestry College Fujian Agriculture and Forestry University Swedish University of Agricultural Sciences Faculty of Forest Science Southern Swedish forest Research Centre

Pinus massoniana Lamb. is a major timber species widely planted in the South China, where the soil is acidic and deficient in phosphorus （P） due to fixation by aluminum and iron. Understanding the physiological responses to rhizospheric insoluble P is essential for enhancing plantation productivity. Thus, a sand culture experiment was conducted with four levels of P treatment （0, 5, 20 g insoluble P and 10 g soluble P）, and 11 P. massoniana elite families. Physiological responses were measured after two months of stress. Compared to the normal soluble P treatment, the insoluble P treatment significantly reduced the proline content and the APase activity in the needles, while it significantly increased the catalase activity by 1.3-fold and malondialdehyde content by 1.2-fold. Soluble protein content was unaffected by the treatments, but chlorophyll content was significantly lower in P-deprived treatment compared with soluble and insoluble P treatments. These physiological responses also exhibited highly significant variation among families （p 〈 0.01）. The findings suggest that increased catalase activities in the presence of insoluble P might be involved in the activation of an anti-oxidation defense mechanism that scavenges the reactive oxygen species elicited by the stress. And this response has a strong genetic control that can be exploited to identify desirable genotypes.

关键词： masson pine phosphorus stress anti-oxidative system lipid peroxidation

Patterns of biomass,carbon,and nitrogen storage distribution dynamics after the invasion of pine forests by Bursaphelenchus xylophilus (Nematoda: Aphelenchoididae) in the three Gorges Reservoir Region

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Journal of Forestry Research 2018年第2期29卷 453-464页

作者： Ruihe Gao Youqing Luo Zhuang Wang Hanjun Yu Juan Shi Beijing Key Laboratory for Forest Pest Control Beijing Forestry University

masson pine stands infected by pine wilt disease(PWD) in the Three Gorges Reservoir Region of central China were surveyed to quantify the immediate responses and subsequent trajectories of biomass,carbon(C),and nitrogen(N) in stand-level major ecosystem *** biomasses of above-and belowground tree components,as well as of the understory,forest floor,and mineral soil(0–40 cm),were determined within each stand.C and N storage were also estimated for each ecosystem *** biomass decreased steadily with the extent of PWD *** biomass ranged from1.97 to 4.16 Mg ha,and the observed value for forest floor biomass was 12.89–22.59 Mg *** highest mean C and N concentrations were found in the stem bark and needles of masson pine,respectively,while the lowest were found in the semi-to fully decomposed layer of the forest floor and stem wood of masson pine,*** C and N storage of aboveground trees,tree roots,and the aboveground ecosystem decreased with the extent ofPWD ***,the C and N contents of the understory,forest floor,and total mineral soil initially declined after PWD infection before recovering over the following several *** result concluded that the biomass,C,and N storage of different forest ecosystem compartments have experienced certain variations following the PWD *** is vital to understand the shifts in stand-level C and N allocation in PWD-damaged forest stands,as well as for predicting the responses of regional and global C and N cycling.

关键词： Carbon Insect outbreak masson pine Nitrogen pine sawyer beetle pine wilt disease

Microwave vacuum drying characteristics of Pinus massoniana wood

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Forestry Studies in China 2007年第1期9卷 63-67页

作者： Li Xian-jun Li Wen-jun Zhang Bi-guang School of Material Science and Engineering Central South University of Forestry and Technology Changsha 410004 P. R. China College of Material Science and Technology Beijing Forestry University Beijing 100083 P. R. China

Microwave-vacuum （MV） drying characteristics of plantation masson pine （Pinus massoniana） were studied experimentally for various levels of microwave radiation time, initial moisture content 0VIC）, vacuum level and wood thickness. The results show that the process of MV drying for wood can be significantly divided into a short accelerating rate drying period, a long constant rate drying period and falling rate drying period, and the second drying period can extend to levels of mean MC below the fiber saturation point. With the increase of initial MC and microwave radiation time, the drying rate of wood increases significantly. The vacuum level affects the drying rate in a slightly positive way. Within the range of 2 to 6 cm, the effects of sample thickness on the drying rate can be negligible.

关键词： wood drying microwave-vacuum masson pine

Relations Between Permeability and Structure of Wood

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Forestry Studies in China 2003年第1期5卷 34-38页

作者： Bao Fucheng ZhaoYouke Lu JianxiongResearch Institute of Wood Industry, Chinese Academy of Forestry, Beijing 100091, P. R. China Research Institute of Wood Industry Chinese Academy of Forestry Beijing 100091 P. R. China

The permeability and the structure of heartwood and sapwood of the solvent-exchange dried and the air-dried greenwood of Chinese-fir (Cunninghamia lanceolata (Lamb.) Hook.) and masson pine (Pinus massoniana Lamb.) were measured in order to study the relations between the permeability and the structure. The results showed that the permeability of sapwood of both the air-dried and the solvent-exchange dried wood was higher than that of heartwood, and the permeability of the solvent-exchanged dried heartwood and sapwood was higher than that of the air-dried. A higher permeability of wood was attributed to, on the one hand, a bigger number of flow path per unit area of the wood perpendicular to the flow direction resulted from a bigger number of unaspirated pits per unit area and a bigger number of effective pit openings per membrane, and on the other hand, a smaller number of tracheid in series connection per unit length parallel to flow direction resulted from a longer tracheid length and an effective tracheid length for permeability.

关键词： Chinese-fir masson pine wood permeability wood fine structure