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Differences and similarities in radial growth of Betula species to climate change

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Journal of Forestry Research 2024年第2期35卷 176-187页

作者： Di Liu Yang An Zhao Li Zhihui wang Yinghui Zhao xiaochun wang Center for Ecological Research Key Laboratory of Sustainable Forest Ecosystem ManagementMinistry of EducationCollege of ForestryNortheast Forestry UniversityHarbin 150040People’s Republic of China Changan Park in Shijiazhuang Shijiazhuang 050000People’s Republic of China Shijiazhuang Landscape Greening Engineering Project Construction Center Shijiazhuang 050000People’s Republic of China Heilongjiang Institute of Meteorological Science Harbin 150030People’s Republic of China School of Life Qufu Normal UniversityQufu 273100People’s Republic of China

Betula platyphylla and Betula costata are important species in mixed broadleaved-Korean pine(Pinus koraiensis)***,the specific ways in which their growth is affected by warm temperatures and drought remain *** address this issue,60 and 62 tree-ring cores of *** and *** were collected in Yichun,*** dendrochronological methods,the response and adaptation of these species to climate change were examined.A“hysteresis effect”was found in the rings of both species,linked to May–September moisture conditions of the previous *** growth of *** was positively correlated with the standardized precipitation-evapotranspiration index(SPEI),the precipitation from September to October of the previous year,and the relative humidity in October of the previous *** of *** is primarily restricted by moisture conditions from September to *** contrast,*** growth is mainly limited by minimum temperatures in May–June of both the previous and current *** droughts,*** had a faster recovery rate compared to *** the context of rising temperatures since 1980,the correlation between *** growth and monthly SPEI became positive and strengthened over time,while the growth of *** showed no conspicuous *** findings suggest that the growth of *** is already affected by warming temperatures,whereas *** may become limited if warming continues or *** change could disrupt the succession of these species,possibly accelerating the succession of pioneer *** results of this research are of great significance for understanding how the growth changes of birch species under warming and drying conditions,and contribute to understanding the structural adaptation of mixed broadleaved-Korean pine(Pinus koraiensis)forests under climate change.

关键词： Tree rings Betula platyphylla Betula costata Climate response Moving correlation Extreme drought

Hybrid concurrency control protocol for data sharing among heterogeneous blockchains

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Frontiers of Computer Science 2024年第3期18卷 1-12页

作者： Tiezheng GUO Zhiwei ZHANG Ye YUAN xiaochun YANG Guoren wang School of Computer Science and Technology Beijing Institute of TechnologyBeijing 100029China School of Computer Science and Engineering Northeastern UniversityShenyang 110167China

With the development of information technology and cloud computing,data sharing has become an important part of scientific *** traditional data sharing,data is stored on a third-party storage platform,which causes the owner to lose control of the *** a result,there are issues of intentional data leakage and tampering by third parties,and the private information contained in the data may lead to more significant ***,data is frequently maintained on multiple storage platforms,posing significant hurdles in terms of enlisting multiple parties to engage in data sharing while maintaining *** this work,we propose a new architecture for applying blockchains to data sharing and achieve efficient and reliable data sharing among heterogeneous *** design a new data sharing transaction mechanism based on the system architecture to protect the security of the raw data and the processing *** also design and implement a hybrid concurrency control protocol to overcome issues caused by the large differences in blockchain performance in our system and to improve the success rate of data sharing *** took Ethereum and Hyperledger Fabric as examples to conduct crossblockchain data sharing *** results show that our system achieves data sharing across heterogeneous blockchains with reasonable performance and has high scalability.

关键词： data sharing blockchain concurrency control protocol crosschain

Advances in geochemical research on nanometer materials

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Progress in Natural Science:Materials International 2006年第4期16卷 331-337页

作者： ZHU Xiaoqing and wang Zhonggang Key Laboratory of Ore Deposit geochemistry, Institute of geochemistry,{3., guiyang 550002, China [a]Key Laboratory of Ore Deposit geochemistry Institute of Geochemistry Chinese Academy of Sciences Guiyang China

Important advances have been made in the field of geochemistry since nanometer science and technology were introduced into the field of geoscience. The nanometer particulates have been discovered in naturally-occurring ore deposits, volcano-eruptive materials and geo-gases, and a more detailed exploration of the metallogenic mechanism of endogenic metallic ore deposits has been conducted. It is considered that some ore-forming metals may transport in the form of native particulates. Because they have very strong capabilities of adsorption, adsorption is always regarded as an important mechanism of metallogenesis under supergenic and low temperature conditions. Therefore, a new technology of ore exploration has also been developed. This paper attempts to review the new advances in geochemical research on nanometer materials, as well as its perspectivess.

关键词： nanometer geochemistry adsorption metallogenic theory prospecting method.

Long-term changes in radial growth of seven tree species in the mixed broadleaf-Korean pine forest in Northeast China:Are deciduous trees favored by climate change?

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Journal of Forestry Research 2024年第5期35卷 63-77页

作者： Xiufang Gong Danyang Yuan Liangjun Zhu Zongshan Li xiaochun wang National Engineering Laboratory for Applied Technology of Forestry and Ecology in South China College of Life Science and TechnologyCentral South University of Forestry and TechnologyChangsha 410004People’s Republic of China Center for Ecological Research and Key Laboratory of Sustainable Forest Ecosystem Management-Ministry of Education School of ForestryNortheast Forestry UniversityHarbin 150040People’s Republic of China State Key Laboratory of Urban and Regional Ecology Research Center for Eco-Environmental SciencesChinese Academy of SciencesBeijing 100085People’s Republic of China

The role of the temperate mixed broadleaf-Korean pine forest(BKF)in global biogeochemical cycles will depend on how the tree species community responds to climate;however,species-specific responses and vulner-abilities of common trees in BKF to extreme climates are poorly *** we used dendrochronological meth-ods to assess radial growth of seven main tree species(Pinus koraiensis,Picea jezoensis,Abies nephrolepis,Fraxinus mandshurica,Phellodendron amurense,Quercus mongolica,and Ulmus davidiana)in an old-growth BKF in response to climate changes in the Xiaoxing’an Mountains and to improve predictions of changes in the tree species *** in most months and winter precipita-tion significantly negatively affected growth of *** and ***,but positively impacted growth of *** and the broadleaf species,especially ***-rica and *** and relative humidity in June significantly positively impacted the growth of most tree *** positive effect of the temperature during the previous non-growing season(PNG)on growth of *** and *** strengthened significantly with rapid warming around 1981,while the impact of PNG temperature on the growth of *** and *** changed from significantly negative to weakly negative or positive at this *** negative response of radial growth of *** and *** to precipitation during the growing season gradually weakened,and the negative response to PNG precipitation was *** the studied species,*** was the most resistant to drought,and *** recovered the best after extreme *** davidiana,*** and *** were more resistant to extreme cold than the other *** warming generally exacerbated the opposite growth patterns of conifer(decline)and broadleaf(increase)*** broadleaf tree species in the old-growth BKF probably will gradually become dominan

关键词： Tree rings Extreme climate Resistance and recovery Broad-leaved and Korean pine mixed forest

Accelerating the practical application of MOFs for hydrogen storage——from performance-driven to application-oriented

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Green Energy & Environment 2024年第8期9卷 1193-1198页

作者： Yifan wang Jinghui Wu Yidi Gao Keqing Li Chi wang xiaochun Cui Mingxin Huo Xianze wang Science and Technology Innovation Center for Municipal Wastewater Treatment and Water Quality Protection Northeast Normal University Engineering Research Center of Low-Carbon Treatment and Green Development of Polluted Water in Northeast China Ministry of Education School of Environment Northeast Normal University Key Laboratory of Songliao Aquatic Environment Ministry of Education Jilin Jianzhu University

Metal-organic frameworks(MOFs) are highly promising porous materials known for their exceptional porosity, extensive surface area, and customizable pore structures, making them an ideal solution for hydrogen storage. However, most MOFs research remains confined to the laboratory, lacking practical applications. To address this, the author proposes a shift towards practical applications, the creation of a comprehensive MOFs database, alignment of synthesis with practical considerations, and diversification of MOFs applications. These steps are crucial for harnessing the full potential of MOFs in real-world energy challenges.

关键词： Metal–organic frameworks Hydrogen gas storage Molecular simulation Computational chemistry Machine learning

Gold occurrence mechanism of fine disseminated gold deposits

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chinese Science Bulletin 1999年第S2期44卷 18-20页

作者： wang xiaochun and ZHANG Zheru Institute of geochemistry,{3., guiyang 550002, China Institute of geochemistry Chinese Academy of Sciences Guiyang 550002 China

THE fine disseminated gold deposits are widely distributed in the southwestern China and western UnitedStates. They have a mineral association of pyrite, arsenopyrite, marcasite, realgar, orpiment, stibnite,cinnabar, quartz, calcite and barite, and an element association of gold, arsenic, antimony, mercury,thallium and barium. Gold occurs as disseminated and in small size. This note aims to discuss the disseminated nature and micron size of the gold.

关键词： gold mechanism fine disseminated gold deposit.

Oxygen isotopic (^(17)O-^(18)O) heterogeneity in Archaean continental nucleus, North China Craton

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chinese Science Bulletin 1999年第24期44卷 2267-2269页

作者： LIU Jianzhong, ZHANG Fuqin, LI Chunlai and wang Shijie Institute of geochemistry , chinese academy of sciences ,{3. , China Institute of Geophysics , chinese academy of sciences , Beijing 100101 , China Institute of geochemistry Chinese Academy of Sciences Guiyang China Institute of Geophysics Chinese Academy of Sciences Beijing China

The oxygen isotopic data for amphibolites from Archaean continental nucleus, North China Craton indicate that ( i ) the evolving lines structured by the data are parallel to the geoselenic evolving line, which means that the parent materials of these continental nucleus o-riginated from solar matter; ( ii ) different intercepts for these evolving lines manifest that oxy-

关键词： North China Craton oxygen isotope (I7O-18O ) heterogeneity.

PROGRESS OF SMCE CHEMISTRY RESEARCH IN CHINA DURING 1995─1997

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空间科学学报 1998年第S1期18卷 21-26页

作者： wang Shi-jie OUYANG Zi-yuan (State Key Laboratorp of Environmental geochemistry,Institute of geochemistry, The{3., guiyang 550002)

Over the past years chinese space chemists have done much work on space chemistry and related disciplines, especially on the solar nebular evolution,meteorjtes, comparative planetology and the origin and evolution of ... 详细信息

关键词： Progress Space chemistry

Two-stage correlation between pH and REE concentration and pattern in rivers

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chinese Science Bulletin 1999年第S2期44卷 106-107页

作者： wang Zhongliang and LIU Congqiang State Key Laboratory of Environmental geochemistry, Institute of geochemistry,{3., guiyang 550002, China State Key Laboratory of Environmental geochemistry Institute of Geochemistry Chinese Academy of Sciences Guiyang 550002 China

DUE to the unique chemical coherence and slight systematic difference properties, the REEs are extensively used as tracers for origin and evolution of the earth and its geology compositions （involved naturalwaters）. Soluble REE concentration in rivers is very low (10-12), and has a typical heavy REE enrichedpattern relative to the North American Shale Composite （NASC） than those of upper crust, suspendedmaterials and sediments. Negative Ce anomalies were widely observed in most of rivers. The behavior of REE in rivers can be affected by geology and chemical weathering of drainage basin,concentration and species of colloids and organs, major anions, pH, microbe action and so on. Especially pH is an important factor controlling the chemistry of water

关键词： rivers REE pattern pH two-stage correlation.