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White oak (Quercus fabri Hance) regenerated stump sprouts show few senescence symptoms during 40 years of growth in a natural forest

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Forest Ecosystems 2021年第1期8卷 139-150页

作者： honggang sun Sisheng Wu Liwen Wu Research Institute of Subtropical Forestry Chinese Academy of ForestryHangzhou 311400China

Background:The relationship between physiological age of parental trees and lifespan of clonal offspring is *** oak(Quercus fabri Hance)has a high sprouting capability after harvest,with the regenerated sprouts being typical clonal *** determine whether regenerated sprouts undergo rapid senescence compared with the parent,the senescence levels of 5-,10-,20-and 40-year-old regenerated stump sprouts in a natural forest were *** antioxidative abilities and transcriptomes in these leaves and shoots were ***:Older regenerated sprouts still had robust antioxidative systems,with 40-year-old sprouts having lower peroxidation product levels but similar antioxidative enzyme activity levels compared with 5-year-old *** leaves had greater transcriptional activities in pathways related to cell growth and division than younger ***,older sprouts had some unhealthy characteristics,such as increased base excision repair levels and upregulated phagosome,proteasome and glycerophospholipid metabolism pathways in 40-year-old leaves,which indicates that DNA damage and tissue remodeling occurred more frequently than in younger ***,plant-pathogen interactions and MAPK signals pathways were upregulated in older shoots,which indicates that older shoots suffered from more pathogen-related biotic ***:The 40-year-old sprouts still had the same vitality level as the 5-year-old sprouts,although the former had some unhealthy *** conclude that during their first 40 years of growth,regenerated stump sprouts do not begin to senesce,and that physiological age of parental trees does not significantly affect the lifespan of its clonal offspring.

关键词： Sprout Regeneration Senescence White oak Vegetative propagation

镁铝合金添加剂对SiC-MgAl_(2)O_(4)材料显微结构和性能的影响

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材料导报 2024年第16期38卷 75-80页

作者：王梦强陈留刚孙红刚杜一昊司瑶晨李红霞郑州大学材料科学与工程学院河南省高温功能材料重点实验室郑州450001 中钢集团洛阳耐火材料研究院有限公司先进耐火材料国家重点实验室河南洛阳471039 北京科技大学材料科学与工程学院北京100083

为探索煤气化用耐火材料的无铬化,本研究采用碳化硅颗粒和镁铝尖晶石细粉为主要原料制备SiC-MgAl_(2)O_(4)复合耐火材料,于流动氮气中500~1450℃热处理,对比未添加和添加4%(质量分数)镁铝合金粉的复合材料在热处理升温过程中的微观结构... 详细信息

为探索煤气化用耐火材料的无铬化,本研究采用碳化硅颗粒和镁铝尖晶石细粉为主要原料制备SiC-MgAl_(2)O_(4)复合耐火材料,于流动氮气中500~1450℃热处理,对比未添加和添加4%(质量分数)镁铝合金粉的复合材料在热处理升温过程中的微观结构及性能变化,探究镁铝合金氮化烧成中形成的低维相对SiC-MgAl_(2)O_(4)复合材料性能的改善效果。结果表明,镁铝合金与热处理环境中的N 2、O_(2)的反应温度区间为650~800℃,主要反应产物为AlN和MgO。添加镁铝合金后的试样在700℃形成蜂窝状MgAl_(2)O_(4)尖晶石,增强了SiC骨料和MgAl_(2)O_(4)基质间的结合,此时试样的常温力学强度达到最高;900~1300℃时,MgAl_(2)O_(4)尖晶石由蜂窝状转变为棒状,1300~1500℃时,其再转变为片状、粒状的MgAlON尖晶石,这些形貌和物相的转变伴随体积膨胀,导致试样的强度小幅下降。镁铝合金的添加能使SiC-MgAl_(2)O_(4)在较低温度热处理下原位形成尖晶石,从而提高材料的力学性能。

关键词：复合耐火材料镁铝尖晶石氮化反应镁铝合金

混交对杉木和山杜英混交林生长、结构和生产力的影响

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植物研究 2024年第2期44卷 307-320页

作者：周浩然孙洪刚张鹏韩媛媛李文华东北林业大学林学院森林生态系统可持续经营教育部重点实验室哈尔滨150040 中国林业科学研究院亚热带林业研究所杭州311400 北华大学林学院吉林132013

为探究杉木(Cunninghamia lanceolata)与山杜英(Elaeocarpus sylvestris)的混交效应,以景德镇枫树山林场20年生杉木纯林、山杜英纯林和杉木-山杜英混交林为研究对象,每种林分类型设置3种坡位(上坡、中坡和下坡),分析树种混交对林分生长... 详细信息

为探究杉木(Cunninghamia lanceolata)与山杜英(Elaeocarpus sylvestris)的混交效应,以景德镇枫树山林场20年生杉木纯林、山杜英纯林和杉木-山杜英混交林为研究对象,每种林分类型设置3种坡位(上坡、中坡和下坡),分析树种混交对林分生长的影响,并分别探究混交效应对立地条件和生境因子的响应。结果表明:混交林蓄积较预期蓄积增加5%,表现略微增产;混交林中杉木蓄积较杉木纯林增加15%,混交林中山杜英蓄积较山杜英纯林减少13%。相对于纯林,两树种直径分布特征对混交的响应呈相反趋势,混交林中杉木直径分布峰值向高阶移动,而混交林中山杜英直径分布峰值向低阶移动。混交林及其纯林粗根直径-胸径的异速生长分析表明,混交林中杉木生长侧重于树干生长,而山杜英生长侧重于根系生长;无论林型和树种,坡位由上到下,林木生长会侧重于树干生长。杉木-山杜英混交效应与地位指数呈显著负相关(P<0.05),土壤有效磷是混交林生长的主要限制因子。杉木与山杜英混交可促进林分生长,且混交林对较差立地条件有更好的适应性。

关键词：混交林林分生产力立地质量混交效应异速生长

Radial growth and non-structural carbohydrate partitioning response to resin tapping of slash pine(Pinus elliottii ***)

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Journal of Forestry Research 2022年第2期33卷 423-433页

作者： Baoguo Du Qifu Luan Zhanglin Ni honggang sun Jingmin Jiang College of Life Science and Biotechnology Ecological and Security Key Laboratory of Sichuan ProvinceMianyang Normal UniversityMianyang 621000People’s Republic of China Chair of Tree Physiology Institute of Forest SciencesAlbert Ludwigs-Universitat FreiburgGeorges-Köhler-Allee 5379110 FreiburgGermany Institute of Subtropical Forestry Research of the Chinese Academy of Forestry Fuyang 311400People’s Republic of China

Slash pine(Pinus elliottii ***)is a resin-producing species grown worldwide for significant economic benefits for wood *** tapping cre-ates a carbon sink at the expense of carbon allocation for growth and consequently,wood production may be ***-structural carbohydrates comprising starch and sugars stored in plant organs,may serve as intermediate pools between assimilation and ***,the effect of resin tapping between tree growth and non-structural carbo-hydrates is not well *** study investigated(1)the effects of resin tapping on radial growth,(2)the effects of resin tapping on non-structural carbohydrate pools in different compartments,and(3)the feasibility of resin pro-duction without disruption of tree *** one-year-old slash pines were subjected to resin tapping over two suc-cessive ***-structural carbohydrate concentrations in needles,branches,stem phloem,and roots of tapped and untapped trees in summer and winter were determined after the second year of resin *** results showed that tapping had no significant effects on annual *** was the dominant non-structural carbohydrate frac-tion,regardless of tissues and season,and constituted up to 99%of the total non-structural carbohydrates in the phloem and *** and fructose were the dominant sugars;sucrose was *** with the controls,tapped trees showed 26%lower non-structural carbohydrate concen-tration in the phloem above the tapping wound in summer,which was attributable to the decreased abundance of starch,glucose,fructose,and *** winter,the altered non-structural carbohydrate profiles in the phloem above the tap-ping wounding were minimised as a result of recovery of the sugar *** contrast to free sugars,which accu-mulated substantially in needles and branches during winter,starch was enriched in the phloem,roots,and current-year *** results provide evidence fo

关键词： Slash pine Localised effects Non-structural carbohydrate Resin tapping Radial growth

外源多效唑对干旱胁迫下闽楠幼苗抗旱性的影响

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应用生态学报 2024年第10期35卷 2667-2676页

作者：宋艳艳徐培月何功秀胡孔飞及利杨丽丽孙洪刚张勰中南林业科技大学林学院南方林业生态应用技术国家工程实验室湖南景辉农林生态科技有限公司中国林业科学研究院亚热带林业研究所湖南省林业科学院

为明确外源多效唑对闽楠幼苗抗旱性的响应机制，以2年生闽楠幼苗作为试材，采用自然干旱法，研究不同浓度多效唑(25、50、100 mg·L-1)喷施对干旱胁迫下闽楠幼苗光合系统和抗氧化系统的影响。结果表明：干旱胁迫显著减弱闽楠幼苗的光合... 详细信息

为明确外源多效唑对闽楠幼苗抗旱性的响应机制，以2年生闽楠幼苗作为试材，采用自然干旱法，研究不同浓度多效唑(25、50、100 mg·L-1)喷施对干旱胁迫下闽楠幼苗光合系统和抗氧化系统的影响。结果表明：干旱胁迫显著减弱闽楠幼苗的光合作用，打破抗氧化系统的动态平衡，不同浓度多效唑喷施均能有效缓解干旱胁迫下闽楠幼苗受到的胁迫损伤，提升光合系统和抗氧化系统的防御能力，其中100 mg·L-1多效唑处理最为有效。100 mg·L-1多效唑处理下，与干旱处理相比，闽楠幼苗叶片中叶绿素总量显著增加，最高为51.9%，表观光合电子传递速率、光化学淬灭系数、实际光化学量子产量显著提高，最高分别为67.8%、58.4%、59.7%，净光合速率、气孔导度、蒸腾速率显著增长，最高分别为65.5%、65.4%、68.6%。外源100 mg·L-1多效唑通过调控闽楠幼苗光合系统和抗氧化系统提升闽楠幼苗抗旱性的能力最强。

关键词：闽楠多效唑干旱胁迫抗旱性

Phase formation,texture evolutions,and mechanical behaviors of Al0.5CoCr0.8FeNi2.5V0.2 high-entropy alloys upon cold rolling

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Progress in Natural Science:Materials International 2022年第2期32卷 196-205页

作者： Tongtong sun Weidong Song Feilong Shan Kaikai Song Kun Zhang Chuanxiao Peng honggang sun Lina Hu School of Mechanical Electrical & Information Engineering Shandong University State Key Laboratory of Explosion Science and Technology Beijing Institute of Technology CAS Key Laboratory of Microgravity (National Microgravity Laboratory) Institute of Mechanics Chinese Academy of Sciences Key Laboratory for Liquid-Solid Structural Evolution & Processing of Materials (Ministry of Education) Shandong University

The cold rolling(CR) reduction dependence of microstructure evolutions and mechanical properties for Al0.5CoCr0.8FeNi2.5V0.2high-entropy alloy(HEA) were *** HEA remains FCC structures consisting of nanoscale ordered L12phase,confirming the phase formation *** increasing CR reduction,the textures transform from random ones to FCC rolling ones accompanied by dense slip bands and deformation *** a 50% CR reduction,the deformation textures started to become evident and were governed by typical {111}F,{110}Goss and {112}Cu texture *** the CR reduction approached 90%,the deformation textures mainly contained the {110}A,{114}X,and {112}Cu texture *** a result,both Vickers hardness and ultimate strength increased,but the ductility decreased *** enhanced strength should be attributed to the anisotropy and work hardening behavior from *** plastic deformation for the samples under low CR reductions was dominated by deformation twins and slip ***,under high CR reductions,the textures severely impeded the further propagation of pre-existing slip bands,leading to the rapid decrease of ***,the CR reduction should be carefully designed before optimal heat treatments to enhance the strength and ductility synergy.

关键词： High-entropy alloys Cold rolling Texture Mechanical property Ductility

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亚热带生态系统5种修复树种的光合特征

东北林业大学学报 2024年第5期52卷 28-33,48页

作者：袁媛徐克芹曾平生姚甲宝孙洪刚欧阳琼肖斌中国林业科学研究院亚热带林业实验中心江西·分宜336600 中国林业科学研究院亚热带林业研究所

分析不同树种生长状况以及光合特征和不同树种光合能力的差异,为提高低效公益林质量提供依据。以苦槠(Castanopsis sclerophylla)、木荷(Schima superba)、浙江楠(Phoebe chekiangensis)、刨花楠(Machilus pauhoi)和红楠(Machilus thunbergii)等5种亚热带地区生态修复树种幼苗为试验对象,测定其生长指标、叶绿素质量分数、光合指标和叶绿素荧光指标,采用直角双曲线修正模型进行光响应曲线拟合以及估算光响应特征参数,并对各项指标进行单因素方差分析和相关性分析。结果表明:不同树种的生长指标和叶绿素质量分数之间存在显著差异(P<0.05);不同树种的光响应曲线均呈现出随光合有效辐射增加先直线上升后缓慢增高再有所下降的变化趋势,且光合特征参数存在显著差异(P<0.05);5种树种的净光合速率(Pn)、气孔导度(Gs)、胞间CO_(2)摩尔分数(Ci)之间存在显著性差异(P<0.05);光系统(PS)Ⅱ潜在荧光活性(Fv/Fo)和光系统(PS)Ⅱ最大光化学效率(Fv/Fm)表现为苦槠显著高于木荷、浙江楠和刨花楠;生长特征参数、光响应曲线特征参数和叶绿素荧光参数之间存在较强的相关性。因此,不同树种光环境适应情况差异较大,苦槠阳性特征显著,可选择低效公益林改造的林窗中心位置进行栽植;木荷对光环境适应范围广,可以作为林窗近中心位置的补植树种;浙江楠、刨花楠和红楠均属于耐阴性较强的树种,可选择林窗边缘位置或者阴坡、半阴坡林窗进行补植。

关键词：生态修复亚热带树种光合特征低效公益林质量提升

Thermodynamic Evaluation of Cr_2O_3-Al_2O_3 Refractory Corrosion by Smelting Reduction Ironmaking Slag

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China's Refractories 2015年第2期24卷 6-10页

作者： ZHAO Shixian CAI Binli LI Pengtao sun honggang WANG Gang State Key Laboratory of Advanced Refractories Sinosteel Luoyang Institute of Refractories Research Co.Ltd.

The interfacial reactions of Cr2O3- Al2O3 refractory materials with smelting reduction ironmaking slag were investigated by thermodynamic modeling. The calculation results indicated that different spinel phases were produced after the interactions between the slag and three types of refractory materials（ 10Cr2O3- 90Al2O3,50Cr2O3- 50Al2O3 and 90Cr2O3- 10Al2O3） at 1 500℃. Increased contents of Al2O3 and Cr2O3in the remained liquid slag after interaction implied the dissolution of refractory. Thermodynamic modeling predicted that the process of dissolution might lead to much deeper penetration into the refractory materials by the present compositional slag. Accordingly,corrosion testing was also conducted to validate the thermodynamic prediction.

关键词： chrome oxide-alumina refractory corrosion thermodynamic spinel

High Temperature Interactions of Chrome Oxide Free Refractories with Coal Slag Under Simulated Gasification Conditions

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China's Refractories 2020年第2期29卷 1-5页

作者： ZHAO Shixian LI Hongxia sun honggang CAI Binli WANG Lan KANG Yina Sinosteel Luoyang Institute of Refractories Research Co. Ltd.Luoyang 471039China

Chrome oxide free refractories have significant economic benefits for the development of gasification *** based and SiC based refractories are corroded by coal slag at 1500℃under reducing ***,interactions between refractory materials and molten slag are also predicted by thermodynamic calculations under the same *** results indicate that spinel based refractories are corroded by dissolution of molten slag,while SiC based refractories are corroded by oxidation of CO and *** of the spinel and SiC based refractories show good corrosion resistance against coal slag by the present experimental ***,preliminary developed spinel-SiC composite materials are prepared and corroded by coal slag as well,the research of which shows great potential to be used in slagging gasifiers.

关键词： chrome oxide free refractories corrosion gasification thermodynamic calculation