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Assessing spatiotemporal variations of forest carbon density using bi-temporal discrete aerial laser scanning data in Chinese boreal forests

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Forest Ecosystems 2023年第5期10卷 547-560页

作者： Zhiyong Qi Shiming li Yong Pang guang Zheng Dan Kong Zengyuan li Research Institute of Forest Resource Information Techniques Chinese Academy of ForestryBeijing100091China Key Laboratory of Forestry Remote Sensing and Information System National Forestry and Grassland AdministrationBeijing100091China National Forestry and Grassland Science Data Center Beijing100091China International Institute for Earth System Science Nanjing UniversityNanjing210023China

Assessing the changes in forest carbon stocks over time is critical for monitoring carbon dynamics,estimating the balance between carbon uptake and release from forests,and providing key insights into climate change *** this study,we quantitatively characterized spatiotemporal variations in aboveground carbon density(ACD)in boreal natural forests in the Greater Khingan Mountains(GKM)region using bi-temporal discrete aerial laser scanning(ALS)data acquired in 2012 and ***,we evaluated the transferability of the proposed design model using forest field plot data and produced a wall-to-wall map of ACD changes for the entire study area from 2012 to 2016 at a grid size of 30 *** addition,we investigated the relationships between carbon dynamics and the dominant tree species,age groups,and topography of undisturbed forested areas to better understand ACD variations by employing heterogeneous forest canopy structural *** results showed that the performance of the temporally transferable model(R^(2)=0.87,rRMSE=18.25%),which included stable variables,was statistically equivalent to that obtained from the model fitted directly by the 2016 field plots(R^(2)=0.87,rRMSE=17.47%).The average rate of change in carbon sequestration across the entire study region was 1.35 Mg⋅ha^(-1)⋅year^(-1) based on the changes in ALS-based ACD values over the course of four *** relative change rates of ACD decreased as the elevation increased,with the highest and lowest ACD growth rates occurring in the middle-aged and mature forest stands,*** Gini coefficient,which represents forest canopy surface structure heterogeneity,is sensitive to carbon dynamics and is a reliable predictor of the relative change rate of *** study demonstrated the applicability of bi-temporal ALS for predicting forest carbon dynamics and fine-scale spatial change *** research contributed to a better understanding of the in-fluence of remote sensing-derive

关键词： Aboveground carbon density bi-temporal ALS Carbon dynamics Temporal transferability Gini coefficient

Synthesis and Crystal Structure of a Novel Tetravanadate Modified by Chiral Racemoid Zirconium Complex

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Chinese Journal of Structural Chemistry 2006年第8期25卷 979-984页

作者： WANG Qing-Wei SHI lin-Fang GAO guang-Gang li Chuan-bi EAN liang Chemistry College Jilin Normal University Siping 136000 China Chemistry College Jilin University Changchun 130000 China

[Zr（phen）4（H2O）4O2（V4O12）]（phen）2 1 （phen = 1,10-phenanthroline） was synthesized under hydrothermal condition. The crystal of 1 belongs to triclinic, space group P1^- with a = 10.6334（8）, b = 11.9201（8）, c = 14.6505（10） A, α = 69.9980（10）, β = 84.9240（10）, γ = 84-1300（10）°, V = 1733.0（2） A^3, Z = 1, Mr = 1672.27, Dc = 1.602 g/cm^3, C72H56N12O18V4Zr, F（000） = 848, μ（MoKa） = 0.747 mm^-1, S = 0.957, R = 0.0504 and wR = 0.1173 for 4011 observed reflections （1 〉 20（I））. The crystal structure of 1 could be discussed in terms of {Zr（phen）2（H2O）2O2}, un-coordinated 1,10-phenanthroline molecules and { V4O12 } unit. In { Zr（phen）2（H2O）2O2 }, the coordination geometry of zirconium is a dodecahedron, but {V4O12} unit is constructed from four apex-sharing {VO4} tetrahedra. Furthermore, {V4O12} links with two {Zr（phen）2（H2O）2O2} units via two bridging oxygen atoms. Interestingly, the two {Zr（phen）2（H2O）2O2} units display D- and L-enantiomers, respectively, upon which the whole molecule represents a racemoid configuration.

关键词： crystal structure V-O tetrahedron 1,10-phenanthroline

Catalytic Oxidation of Hexanol to Hexanal with H_2O_2 Over P-W Heteropoly Compounds

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Chemical Research in Chinese Universities 2001年第3期17卷 293-298页

作者： ZHOU guang-dong GUO Xiao-hong liU Yan bi Ying-li ZHEN Kai-ji Department of Chemistry Jilin UniversityChangchun 130023P.R.China

The syntheses of Keggin and Dawson-structural phospho-tungsto heteropoly compounds and their Peroxo-derivatives(PCWP), and the catalytic performance over this series of catalysts for the selective oxidation of hexanol to hexylaldehyde are reported. By means of IR, NMR and UV-DRS techniques the catalysts were characterized and a comparison of the structural properties of these catalysts before and after the reaction was made. The correlation between the catalytic performance and the structure of this series of catalysts was discussed as well.

关键词： P-W Heteropoly compound Hexanol Hexanal

Tribological behaviour of biomedical Ti–Zr-based shape memory alloys

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Rare Metals 2017年第6期36卷 478-484页

作者： Wen-Tao Qu Xu-guang Sun bi-Fei Yuan Kang-Ming li Zhen-Guo Wang Yan li School of Mechanical Engineering Xi'an Shiyou UniversityXi'an 710065 China School of Materials Science and Engineering Beihang University Beijing 100191 China Key Laboratory of Aerospace Materials and Performance(Ministry of Education) Beihang University Beijing 100191China

The tribological behaviour of Ti-30Zr, Ti-20Zr-10Nb and Ti-19Zr-10Nb-1Fe alloys was investigated using reciprocating friction and wear tests. X-ray diffraction（XRD） results indicate that Ti-30Zr, Ti-20Zr-10Nb and Ti-19Zr-10Nb-1Fe alloys are composed of hexagonal a＇-martensite, orthorhombic a＇＇-martensite and bcc β phases,respectively. Ti-30Zr alloy has the highest hardness of HV（273.1 ± 9.3）, while Ti-20Zr-10Nb alloy exhibits the lowest hardness of HV（235.2 ± 20.4） among all the *** tribological results indicate that Ti-30Zr alloy shows the best wear resistance among these alloys, corresponding to the minimum average friction coefficient of 0.052 and the lowest wear rate of 6.4x10^-4mm3·N^-1·m^-1. Ti-20Zr-10Nb alloy displays better wear resistance than Ti-19Zr-10Nb-1Fe alloy, because the iron oxide is easy to fall off and less Nb2O5 films form on the worn surface of the *** and abrasive wear in association with adhesive wear are the main wear mechanism of these alloys.

关键词： biomedical material Shape memory alloyTi-Zr Tribology

Overview of organic anion transporters and organic anion transporter polypeptides and their roles in the liver

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World Journal of Clinical Cases 2019年第23期7卷 3915-3933页

作者： Ting-Ting li Jia-Xing An Jing-Yu Xu bi-guang Tuo Department of Gastroenterology Affiliated Hospital Zunyi Medical University

Organic anion transporters(OATs)and organic anion transporter polypeptides(OATPs)are classified within two SLC superfamilies,namely,the SLC22A superfamily and the SLCO superfamily(formerly the SLC21A family),*** are expressed in many tissues,such as the liver and kidney,and mediate the absorption and excretion of many endogenous and exogenous substances,including various *** are composed of 12 transmembrane polypeptide chains with the C-terminus and the N-terminus located in the cell *** and OATPs are abundantly expressed in the liver,where they mainly promote the uptake of various endogenous substrates such as bile acids and various exogenous drugs such as antifibrotic and anticancer ***,differences in the locations of glycosylation sites,phosphorylation sites,and amino acids in the OAT and OATP structures lead to different substrates being transported to the liver,which ultimately results in their different roles in the *** date,few articles have addressed these aspects of OAT and OATP structures,and we study further the similarities and differences in their structures,tissue distribution,substrates,and roles in liver diseases.

关键词： Organic anion Substrate transport liver fibrosis liver cirrhosis liver cancer Targeted therapy

Mapping of Mutant Gene prbs Controlling Poly-Row-and-Branched Spike in Barley (Hordeum vulgare L.)

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Agricultural Sciences in China 2011年第10期10卷 1501-1505页

作者： HUANG bi-guang WU Wei-ren Key Laboratory for Genetics Breeding and Multiple Utilization of Crops Ministry of Education/College of Crop Science Fujian Agriculture and Forestry University Fuzhou 350002 P.R.China

A row-type mutant of barley named poly-row-and-branched spike （prbs） was previously obtained from a two-rowed cultivar Pudamai-2 after treated by inflorescence soaking in maize total DNA solution. The mutant produces branched spikes with irregular multiple rows. Genetic analysis indicated that the mutant phenotype was caused by a recessive gene prbs, and the PRBS locus had a recessive epistatic effect on an independent locus （denoted as Vrsx） conferring the variation of two-rowed spike vs. six-rowed spike. This study aimed to map PRBS as well as Vrsx using simple sequence repeats （SSR） markers. We developed an F2 population from a cross between the prbs mutant and a six-rowed cultivar Putianwudu for the gene mapping. As the two target loci interacted to result in a segregation ratio of two-rowed type：six-rowed type：prbs=9：3：4 in the population, we adopted a special strategy to map the two loci. PRBS was mapped between SSR markers HvLTPPB and Bmag0508A on the short arm of chromosome 3H, with distances of 24.7 and 14.3 cM to the two markers, respectively. Vrsx was mapped between SSR markers Bmag0125 and Bmag0378 on chromosome 2H, with distances of 6.9 and 15.3 cM to the two markers, respectively. This suggests that Vrsx should be the known locus Vrs1, which predominantly controls row-type variation in barley cultivars, and PRBS is a new locus related to the row type of spikes in barley.

关键词： barley row type prbs mapping SSR

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一个合成基因网络的电路模型构建

天津科技大学学报 2011年第4期26卷 22-25页

作者：李光壁孟令贞刘清岱张芹王志伟天津科技大学海洋科学与工程学院天津300457 天津市食品安全管理与战略研究中心天津300457 天津科技大学食品工程与生物技术学院天津300457

在系统生物学研究中,使用已熟知的工程技术来研究基因网络的行为是公认的有效方法.本文基于一个与细胞振荡放大有关的合成基因网络模型,构建了它的电路模型.使用非线性电路设计方法来维持原模型的非线性特性.分别使用运算放大器方法和MO... 详细信息

在系统生物学研究中,使用已熟知的工程技术来研究基因网络的行为是公认的有效方法.本文基于一个与细胞振荡放大有关的合成基因网络模型,构建了它的电路模型.使用非线性电路设计方法来维持原模型的非线性特性.分别使用运算放大器方法和MOSFET晶体管方法构建了两种电路模型,并进行了简单比较.结果可为利用电路模型研究更复杂的基因网络提供了一种可能性.

关键词：基因网络电路工程化非线性相干振荡

Constant charge method or constant potential method:Which is better for molecular modeling of electrical double layers?

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Journal of Energy Chemistry 2024年第7期94卷 54-60页

作者： liang Zeng Xi Tan Xiangyu Ji Shiqi li Jinkai Zhang Jiaxing Peng Sheng bi guang Feng State Key Laboratory of Coal Combustion Schoolof Energy and PowerEngineeringHuazhong Universityof Science and Technology(HUST)Wuhan 430074HubeiChina Sorbonne Universite CNRSPhysico-chimie des Electrolytes et Nanosystemes InterfaciauxPHENIXF-75005 ParisFrance

In molecular modeling of electrical double layers(EDLs),the constant charge method(CCM)is prized for its computational efficiency but cannot maintain electrode equipotentiality like the more resourceintensive constant potential method(CPM),potentially leading to *** certain scenarios,CCM can yield results identical to ***,there are no clear guidelines to determine when CCM is sufficient and when CPM is ***,we conduct a series of molecular simulations across various electrodes and electrolytes to present a comprehensive comparison between CCM and CPM under different charging *** reveal that CCM approximates CPM effectively in capturing equilibrium EDL and current-driven dynamics in open electrode systems featuring ionic liquids or regular concentration aqueous electrolytes,while CPM is indispensable in scenarios involving organic and highly concentrated aqueous electrolytes,nanoconfinement effects,and voltage-driven *** work helps to select appropriate methods for modeling EDL systems,prioritizing accuracy while considering computationalefficiency.

关键词： Electrochemical interface Molecular dynamics Electrode polarization modeling Nanoconfinement effect

Synthesis and Characterization of CdSe Nanocrystals Capped by CdS

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Chemical Research in Chinese Universities 2003年第3期19卷 269-274页

作者： SUXing-guang liNZhang-bi HUHai ZHANGJia-hua JINQin-han LaboratoryofExcitedStateProcesses ChineseAcademyofSciencesChangchun130021P.R.China CollegeofChemistry JilinUniversityChangchun130023P.R.China CollegeofChemistry JilinUniversityChangchun130023P.R.China LaboratoryofExcitedStateProcesses ChineseAcademyofSciencesChangchun130021P.R.China

CdSe semiconductor nanocrystals capped by CdS were synthesized in the aqueous solution with 2 mercaptoethanol as the stabilizer. The CdS capping with a higher band gap than that of the core crystallite has successfully eliminated the surface traps. Optical absorption and fluorescence emission spectra were used to probe the effect of CdS passivation on the electronic structure of the nanocrystals. The composite CdSe/CdS nanocrystals exhibit strong, narrow(FWHM≤40 nm) and stable band edge photoluminescence. X ray powder diffraction, transmission electron microscopy and X ray photoelectron spectroscopy were used to analyze the composite nanocrystals and determine their average size, size distribution, shape, internal structure and elemental composition.

关键词： CdSe/CdS Nanocrystal Synthesis Characterization