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Variant Scaling Relationship for Mass-Density Across Tree-Dominated Communities

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Journal of Integrative Plant Biology 2006年第3期48卷 268-277页

作者： Hai-Tao Li Xing-guo han Jian-guo Wu Institute of Geographic Sciences and Natural Resources Research the Chinese Academy of Sciences Beijing 100101 China Laboratory of Quantitative Vegetation Ecology Institute of Botany the Chinese Academy of Sciences Beijing 100093 China Faculty of Ecology Evolution and Environmental Science School of Life Sciences Arizona State University Tempe AZ 85287-4501 USA

The past few decades have seen a resurgence of Interest in biological allometry. Specifically, a number of recent studies has suggested a -4/3 Invariant scaling relationship between mass and density that Is universally valid for tree-dominated communities, regardless of their phyietic affiliation or habitat. In the present study, we test this scaling relationship using a comprehensive forest biomass database, Including 1 266 plots of six blomes and 17 forest types across China. The present study shows that the scaling exponent of the massdensity relationship varies across different tree-dominated communities and habitats. This great variability In the scaling exponent makes any generalization unwarranted. Although Inappropriate regression methods can lead to flawed estimation of the scaling exponent, inconsistency of theoretical framework and empirical patterns may have undermined the validity of previous work.

关键词： allometry mass-density scaling relationship trees.

Lack of Evidence for 3/4 Scaling of Metabolism in Terrestrial Plants

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Journal of Integrative Plant Biology 2005年第10期47卷 1173-1183页

作者： Hai-Tao LI Xing-guo han Jian-guo WU Institute of Geographic Sciences and Natural Resources Research the Chinese Academy of Sciences Beijing 100101 China Laboratory of Quantitative Vegetation Ecology Institute of Botany the Chinese Academy of Sciences Beijing 100093 China Faculty of Ecology Evolution and Environmental Science School of Life Sciences Arizona State University Tempe AZ 85287-4501 USA

Scaling, as the translation of information across spatial, temporal, and organizational scales, is essential to predictions and understanding in all sciences and has become a central issue in ecology. A large body of theoretical and empirical evidence concerning allometric scaling in terrestrial individual plants and plant communities has been constructed around the fractal volume-filling theory of West, Brown, and Enquist （the WBE model）. One of the most thought-provoking findings has been that the metabolic rates of plants, like those of animals, scale with their size as a 3/4 power law. The earliest, single most-important study cited in support of the application of the WBE model to terrestrial plants claims that whole-plant resource use in terrestrial plants scales as the 3/4 power of total mass, as predicted by the WBE model. However, in the present study we show that empirical data actually do not support such a claim. More recent studies cited as evidence for 3/4 scaling also suffer from several statistical and data-related problems. Using a forest biomass dataset including 1 266 plots of 17 main forest types across China, we explored the scaling exponents between tree productivity and tree mass and found no universal value across forest stands. We conclude that there is not sufficient evidence to support the existence of a single constant scaling exponent for the metabolism-biomass relationship for terrestrial plants.

关键词： metabolism 3/4 power scaling terrestrial plants water use.

BEM/FDM Conjugate Heat Transfer Analysis of a Two-dimensional Air-cooled Turbine Blade Boundary Layer

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Journal of Thermal Science 2008年第3期17卷 199-206页

作者： Wang Zhenfeng Yan Peigang guo Zhaoyuan han Wanjin School of Energy Science and Engineering Harbin Institute of Technology Harbin 150001 China

A coupled boundary element method （BEM） and finite difference method （FDM） are applied to solve conjugate heat transfer problem of a two-dimensional air-cooled turbine blade boundary layer. A loosely coupled strategy is adopted, in which each set of field equations is solved to provide boundary conditions for the other. The Navier-Stokes equations are solved by HIT-NS code. In this code, the FDM is adopted and is used to resolve the convective heat transfer in the fluid region. The BEM code is used to resolve the conduction heat transfer in the solid region. An iterated convergence criterion is the continuity of temperature and heat flux at the fluid-solid interface. The numerical results from the BEM adopted in this paper are in good agreement with the results of analytical solution and the results of commercial code, such as Fluent 6.2. The BEM avoids the complicated mesh needed in other computation method and saves the computation time. The results prove that the BEM adopted in this paper can give the same precision in numerical results with less boundary points. Comparing the conjugate results with the numerical results of an adiabatic wall flow solution, it reveals a significant difference in the distribution of metal temperatures. The results from conjugate heat transfer analysis are more accurate and they are closer to realistic thermal environment of turbines.

关键词： Conjugate heat transfer Boundary elements Finite difference Air-cooled gas turbine.

A New Monodisperse Reactive Resin with Active Groups on the Particle Surface

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Chinese Chemical Letters 2001年第1期12卷 71-72页

作者： Yu han guo Tian Sheng SU Center for Molecule Science Institute of ChemistryThe Chinese Academy of SciencesBeijing 100080

A novel reactive resin as active support was synthesized by an improved method based on seed swelling and surface coating polymerization. The resin is monosized beads with inner nucleus of cross-linked polymer and sur... 详细信息

关键词： Monosized polymer beads reactive resin active support

Experimental investigation of combustion mechanisms of kerosene-fueled scramjet engines with double-cavity flameholders

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Acta Mechanica Sinica 2011年第6期27卷 891-897页

作者： Yu Pan Jian-guo Tan Jian-han Liang Wei-Dong Liu Zhen-guo Wang Department of Aerospace and Material National University of Defense and Technology 410073 Changsha China

A scramjet combustor with double cavitybased flameholders was experimentally studied in a directconnected test bed with the inflow conditions of M = 2.64,Pt = 1.84 MPa,Tt = 1 300 *** ignition and selfsustained combustion with room temperature kerosene was achieved using pilot hydrogen,and kerosene was vertically injected into the combustor through 4×φ 0.5 mm holes mounted on the *** different equivalence ratios and different injection schemes with both tandem cavities and parallel cavities,flow fields were obtained and compared using a high speed camera and a Schlieren *** revealed that the combustor inside the flow field was greatly influenced by the cavity installation scheme,cavities in tandem easily to form a single side flame distribution,and cavities in parallel are more likely to form a joint flame,forming a choked combustion *** supersonic combustion flame was a kind of diffusion flame and there were two kinds of combustion *** the unchoked combustion mode,both subsonic and supersonic combustion regions *** in the choked mode,the combustion region was fully subsonic with strong shock propagating *** also showed that there was a balance point between the boundary separation and shock enhanced combustion,depending on the intensity of heat release.

关键词： Scramjet. Supersonic combustion. Flame structure Cavity flameholder

Quantitative Trait Loci Mapping of Leaf Morphological Traits and Chlorophyll Content in Cultivated Tetraploid Cotton

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Journal of Integrative Plant Biology 2005年第11期47卷 1382-1390页

作者： Xian-Liang SONG Wang-Zhen guo Zhi-guo han Tian-Zhen ZhanG State Key Laboratory of Crop Genetics and Germplasm Enhancement Cotton Research Institute Nanjing Agricultural University Nanjing 210095 China Shandong Agricultural University College of Agronomy Taian 271018 China

Genetic mapping provides a powerful tool for quantitative trait loci （QTL） analysis at the molecular level. A simple sequence repeat （SSR） genetic map containing 590 markers and a BCI population from two cultivated tetraploid cotton （Gossypium hirsutum L.） cultivars, namely TM-1 and Hai 7124 （G. barbadense L.）, were used to map and analyze QTL using the composite interval mapping （CIM） method. Thirty one QTLs, 10 for lobe length, 13 for lobe width, six for lobe angle, and two for leaf chlorophyll content, were detected on 15 chromosomes or linkage groups at logarithm of odds （LOD）≥2.0, of which 15 were found for leaf morphology at LOD≥3.0. The genetic effects of the QTL were estimated. These results are fundamental for marker-assisted selection （MAS） of these traits in tetraploid cotton breeding.

关键词： chlorophyll cotton leaf morphology quantitative trait locus mapping simple sequencerepeat.

A Note on Symplectic Algorithm

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Communications in Theoretical Physics 2001年第7期36卷 11-18页

作者： guo han-Ying LI Yu-Qi WU Ke Institute of Theoretical Physics Academia Sinica P.O. Box 2735 Beijing 100080 China Institute of Theoretical Physics Academia Sinica P.O. Box 2735 Beijing 100080 China Institute of Theoretical Physics Academia Sinica P.O. Box 2735 Beijing 100080 China

We present the symplectic algorithm in the Lagrangian formalism for the Hamiltonian systems by virtue of the noncommutative differential calculus with respect to the discrete time and the Euler-Lagrange cohomological ... 详细信息

关键词： symplectic algorithm, Lagrangian formalism, Euler-Lagrange cohomology

Hybrid Particle Swarm Optimization with Differential Evolution for Numerical and Engineering Optimization

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International Journal of Automation and computing 2018年第1期15卷 103-114页

作者： guo-han Lin Jing Zhang Zhao-Hua Liu College of Electrical and Information Engineering Hunan University College of Electrical and Information Hunan Institute of Engineering School of Information and Electrical Engineering Hunan University of Science and Technology

In this paper, a hybrid particle swarm optimization （PSO） algorithm with differential evolution （DE） is proposed for numerical benchmark problems and optimization of active disturbance rejection controller （ADRC） parameters. A chaotic map with greater Lyapunov exponent is introduced into PSO for balancing the exploration and exploitation abilities of the proposed algorithm. A DE operator is used to help PSO jump out of stagnation. Twelve benchmark function tests from CEC2005 and eight real world opti- mization problems from CEC2011 are used to evaluate the performance of the proposed algorithm. The results show that statistically, the proposed hybrid algorithm has performed consistently well compared to other hybrid variants. Moreover, the simulation results on ADRC parameter optimization show that the optimized ADRC has better robustness and adaptability for nonlinear discrete-time systems with time delays.

关键词： Particle swarm optimization (PSO) active disturbance rejection control (ADRC) differential evolution algorithm chaoticmap parameter tuning.

Flaxseed Lignans Promoted the Growth of Skeletal Muscle in Male Rats and Its Possible Mechanism

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Agricultural Sciences in China 2009年第12期8卷 1511-1516页

作者： ZHOU Wei WANG guo-jie han Zheng-kang Key Laboratory of Animal Physiology and Biochemistry Ministry of Agriculture/Nanjing Agricultural University Nanjing 210095 P. R. China

This study was aimed to determine whether flaxseed lignans could affect the growth of skeletal muscle in male animals and its possible mechanisms. The impact of flaxseed lignans on the skeletal muscle in male rats was determined in vivo. Flaxseed lignans （50 ppm） and daidzein （5 ppm） were added into the basal diets, respectively. The concentrations of serum lignans and daidzein were measured by high performance liquid chromatography （HPLC）, and the serum growth hormone and testosterone （T） levels were analyzed by radioimmunoassay （RIA）, and the expression of estrogen receptor β （ER β） in the soleus muscle and hypothalamus were determined by reverse-transcription polymerase chain reaction （RT-PCR）. Flaxseed lignans and daidzein could significantly improve the feed efficiency and facilitate the weight gain of the femoral muscle in male rats. The ratio of RNA to DNA in the muscles and serum T levels was remarkably increased, whereas, the urea nitrogen concentrations were significantly decreased by flaxseed lignan and/or its metabolites and daidzein. Meanwhile, the expression of ER β in soleus muscle and hypothalamus were both upgraded by the two phytoestrogens. Flaxseed lignan promoted the growth of male rats, and it might be by regulating serum T levels by binding to ER β in the hypothalamus. In turn, it depressed the catabolism of protein and promoted the hypertrophy of skeletal muscle ceils.

关键词： phytoestrogens flaxseed lignans daidzein mammalian lignans skeletal muscle growth