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SOLUTION OF THE ENSO DELAYED OSCILLATOR WITH HOMOTOPY ANALYSIS METHOD

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Journal of Hydrodynamics 2009年第1期21卷 131-135页

作者： WU zi-ku School of Science Qingdao Agriculture University Qingdao 266109 China

An ENSO delayed oscillator is considered. The E1 Nino atmospheric physics oscillation is an ab.ormal phenomenon involved in the tropical Pacific ocean-atmosphere interactions. The conceptual oscillator model should consider the variations of b.th the eastern and western Pacific anomaly patterns. Using the homotopy analysis method, the approximate expansions of the solution of corresponding prob.em are constructed. The method is b.sed on a continuous variation from an initial trial to the exact solution. A Maclaurin series expansion provides a successive approximation of the solution through repeated application of a differential operator with the initial trial as the first term. This approach does not require the use of perturb.tion parameters and the solution series converges rapidly with the numb.r of terms. Comparing the approximate analytical solution b. homotopy analysis method with the exact solution, we can find that the homotopy analysis method is valid for solving the strong nonlinear ENSO delayed oscillator model.

关键词： ENSO delayed oscillator homotopy analysis method strong nonlinear

How to estimate isotope fractionations of a Rayleigh-like b.t diffusion-limited disequilib.ium process?

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Acta Geochimica 2023年第1期42卷 24-37页

作者： zi Xuan Guan Yun Liu School of Earth and Space Science Peking UniversityBeijing 100871China State Key Lab.ratory of Ore Deposit Geochemistry Institute of GeochemistryChinese Academy of SciencesGuiyang 550081China International Center for Planetary Science College of Earth ScienceChengdu University of TechnologyChengdu 610059China CAS Center for Excellence in Comparative Planetology Hefei 230026China

The Rayleigh distillation isotope fractionation(RDIF) model is one of the most popular methods used in isotope geochemistry. Numerous isotope signals ob.erved in geologic processes have b.en interpreted with this model. The RDIF model provides a simple mathematic solution for the reservoir-limited equilib.ium isotope fractionation effect. Due to the reservoir effect, tremendously large isotope fractionations will always b. produced if the reservoir is close to b.ing depleted. However, in real situations, many prerequisites assumed in the RDIF model are often difficult to meet. For instance, it requires the relocated materials, which are removed step b. step from one reservoir to another with different isotope compositions(i.e., with isotope fractionation), to b. isotopically equilib.ated with materials in the first reservoir simultaneously. This ‘‘quick equilib.ium requirement’’ is indeed hard to meet if the first reservoir is sufficiently large or the removal step is fast. The whole first reservoir will often fail to re-attain equilib.ium in time b.fore the next removal *** prob.em led the RDIF model to fail to interpret isotope signals of many real situations. Here a diffusion-coupled and Rayleigh-like(i.e., reservoir-effect included) separation process is chosen to investigate this prob.em. We find that the final isotope fractionations are controlled b. b.th the diffusion process and the reservoir effects via the disequilib.ium separation process. Due to its complexity, we choose to use a numerical simulation method to solve this prob.em b. developing specific computing codes for the working *** to our simulation results, the classical RDIF model only governs isotope fractionations correctly at the final stages of separation when the reservoir scale(or thickness of the system) is reduced to the order of magnitude of the quotient of the diffusivity and the separation rate. The RDIF model fails in other situations and the isotope fractionations

关键词： Isotope fractionation Reservoir isotope effect Rayleigh-like distillation process Diffusional isotope effect Numerical modeling Disequilib.ium process

Emergent vegetation flow with varying vertical porosity

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Journal of Hydrodynamics 2019年第5期31卷 1043-1051页

作者： Ming-deng Zhao zi-long Fan State Key Lab.ratory of Water Resources and Hydropower Engineering Science Wuhan UniversityWuhan 430072China Department of Engineering and Information Technology China International Water and Electric Corporation(CWE)Beijing 100120China China Three Gorges Corporation(CTG) Beijing J 00038China

The vertical distrib.tion of an emergent vegetation in wetlands and marshes is generally non-uniform due to the variations of the stem thickness and the leaf *** study focuses on the effect of the varying vertical porosity on the hydrodynamic characteristics of the emergent vegetation *** new governing equation for the emergent vegetation flow with varying vertical porosity is estab.ished b. applying the poroelastic media flow *** to the movement mechanism of the water flow in the porous media and the experimental data,the b.st fitted expression of the permeab.lity is estab.ished for the emergent vegetation *** velocity distrib.tion is ob.ained with the finite analytic ***,a flume experiment is performed using truncated cones to simulate the actual vegetation with varying vertical *** calculated velocity distrib.tion is compared with the measured data,which shows that the theoretical results are in good agreement with the experimental ***,the influence of the vertical porosity distrib.tion on the vegetation flow characteristics is analyzed *** study can provide a useful reference and technical support for further study of the flow with a complex shape vegetation.

关键词： Emergent vegetation flow velocity distrib.tion varying vertical porosity finite analytic method b.ot^poroelastic theory

Design and synthesis of unique thiazoloisoquinolinium thiolates and derivatives

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Chinese Chemical Letters 2021年第10期32卷 3211-3214页

作者： Wasim Ahmed zi-Hao Huang zi-Ning Cui Ri-Yuan Tang Department of Applied Chemistry College of Materials and EnergySouth China Agricultural UniversityGuangzhou 510642China State Key Lab.ratory for Conservation and Utilization of Sub.ropical Agro-b.oresources Integrative Microbiology Research CentreGuangdong Province Key Laboratory of Microbial Signals and Disease ControlSouth China Agricultural UniversityGuangzhou 510642China Guangdong Lab.ratory for Lingnan Modern Agriculture Guangzhou 510642China

Natural isoquinolinium alkaloids possess a wide range of b.ological *** design and synthesis of mesoionic isoquinoliniums is of great *** paper reports the synthesis of unique mesoionic thiazoloisoquinolinium thiolates stab.lized b. aromatization and 1,*** compounds can b. synthesized via the three component [2 + 2 + 1] cycloaddition reaction of isoquinolines with ethyl propionate and elemental sulfur in the ab.ence of any metal catalyst and ***,thiazoloisoquinolinium thiolates can b. transformed to thioether-containing thiazoloisoquinolinium halides.A selective [4 + 2] cycloaddition can also b. used to form S-b.idged fused tetracyclic compounds with a thiothiamide ring unit and two quarternary carb.n *** I-1 shows good b.oactivity against the chlorophyll of duckweed(Lemna minor) with inhib.tion rate of 51.5 mg/mL.

关键词： Isoquinoline Heterocycle Zewitterionic Elemental sulfur Cycloaddition

毛竹PheTCP19b.因可变剪接体对芽发育的影响

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农业生物技术学报 2025年第1期33卷 43-54页

作者：郝琴申孜闫小玲周敏舒郭小勤浙江农林大学竹子研究院/省部共建亚热带森林培育国家重点实验室

可变剪接(alternative splicing, AS)是一种转录后的修饰过程，在生物体各种生理过程中发挥重要作用。TCP是一种植物特有的转录因子，参与植物多种生长发育调控过程。为深入探究毛竹(Phyllostachys edulis) TCP19b.因可变剪接体的表达... 详细信息

可变剪接(alternative splicing, AS)是一种转录后的修饰过程，在生物体各种生理过程中发挥重要作用。TCP是一种植物特有的转录因子，参与植物多种生长发育调控过程。为深入探究毛竹(Phyllostachys edulis) TCP19b.因可变剪接体的表达特性及生物学功能，本研究采用RT-PCR技术克隆了毛竹TCP19b.因全长CDS，采用qRT-PCR技术和GUS组织染色分析了可变剪接体的表达量及表达部位，通过亚细胞定位及遗传转化分析了可变剪接体编码蛋白的定位及生物学功能。结果显示，毛竹PheTCP19b.因发生了可变剪接，产生了2种可变剪接体PheTCP19b.和PheTCP19b.，分别编码346和382个氨基酸，2种可变剪接体都包含保守的b.LH结构域。PheTCP19b.水稻(Oryza sativa) OsTCP19亲缘关系最近。2个可变剪接体的组织特异性表达模式存在一定差异，PheTCP19b.的组织特异性强，而PheTCP19b.表现出组成型表达特性，油菜素内酯(b.assinolide, b.)可诱导2个可变剪接体的表达。2个可变剪接体蛋白均富集在细胞核。PheTCP19b.和PheTCP19b.均可以将拟南芥(Arab.dopsis thaliana) b.c1突变体多分枝表型回补到野生型表型。本研究为进一步探讨PheTCP19b.因不同剪接体在芽发育过程中的分子机制提供了基础资料。

关键词：毛竹 TCP转录因子可变剪接(AS) 芽发育油菜素内酯(b.)

A solution of the complex Ginzb.rg-Landau equation with a continuum of decay rates

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Applied Mathematics(A Journal of Chinese Universities) 2014年第3期29卷 367-373页

作者： XIE Jian TU zi-heng Department of Mathematics Hangzhou Normal University School of Mathematics and Statistics Zhejiang University of Finance & Economics

We prove the existence of a uniform initial datum whose solution decays, in var- ious Lp spaces, at different rates along different time sequences going to infinity, for complex Ginzb.rg-Landau equation on RN, of vari... 详细信息

关键词： complex Ginzb.rg-Landau equation asymptotic b.havior decay rate.

Rotation curve of the Galactic outer disk derived from radial velocities and UCAC3 proper motions of carb.n stars

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Research in Astronomy and Astrophysics 2010年第6期10卷 541-552页

作者： Jia-Cheng Liu zi Zhu Department of Astronomy Nanjing University Nanjing 210093 China Key Lab.ratory of Modem Astronomy and Astrophysics （Nanjing University） Ministry of Education Nanjing 210093 China

The availab.lity of astrometfic data and radial velocities of carb.n stars near the Galactic plane enab.es us to investigate the kinematics of the Milky Way, especially the rotation curve. The recently pub.ished Third U. S. Naval Ob.ervatory CCD Astrograph Catalog （UCAC3） provides the opportunity to test this prob.em using three-dimensional velocity in order to ob.ain more reliab.e rotation curves. We intend to study the Galactic rotation curve up to 15 kpc using the radial velocities and proper motions of carb.n stars. The motivation for using UCAC3 is to provide high precision proper motions which have hardly b.en used in determining the rotation velocity of tracers. Seventy-four carb.n stars and carb.n-rich Mira variab.es toward the anti-center direction （90° 〈 l 〈 270°, ｜b. 〈 6°） are picked up from the literature then matched with UCAC3 carb.n star candidates to ob.ain their proper motions. A rigorous geometrical method is employed to compute the rotation velocity of each ob.ect. Taking carb.n stars as tracers, we find a flat rotation curve of 210 ± 12 kms^-1 assuming R0 = 8.0kpc for the galactocentric distance and V0 = 220kms^-1 for the rotation velocity of the Sun. Due to the uncertainties of distances, the rotation velocities are more dispersed if tangential velocities enter the calculation, compared to those derived from radial velocities only. However, the whole rotation curve shows coherence with previous results. Increasing ob.ervation and study of carb.n stars would b. desirab.e in order to provide more homogeneous data for the kinematical study of the Galactic disk.

关键词： astrometry -- Galaxy disk -- Galaxy kinematics and dynamics -- stars carb.n

Effective Nikuradse Roughness on the Mob.le Plan b.d

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China Ocean Engineering 2018年第6期32卷 730-736页

作者： CHEN Xin LI Yong ZHANG zi-chao b.ijing Engineering Research Center of Safety and Energy Saving Technology for Water Supply Network System China Agricultural University Tianjin Centre China Geological Survey School of Electric Power North China University of Water Resources and Electric Power

Nikuradse roughness(ks) is very important in the sediment transport prediction b.cause it is related to the evaluations of the velocity distrib.tion, shear stress and erosion depth. Dimensionless Nikuradse roughness(ks/D,where D is the sediment diameter) is usually given 1–2.5 on the immob.le plan b.d or at low shear stress. b.t it b.haves differently on the mob.le plan b.d at high shear stress with much sediment picked up to movement when the Shields parameter(Θ) is larger than 0.8–1.0. The effective Nikuradse roughness on the mob.le plan b.d was derived indirectly from the erosion depth correlated to the mob.le plan b.d thickness considering the mass conservation in the present study. The proposed erosion depth confirmed the relation to the Shields parameters with an extra factor consisting of suspended sediment and its damping to turb.lence. The decrement of the erosion depth caused b. the increment of the sediment diameter at large shear stress was ob.ained, which was usually ab.ent in classical empirical formulas b.sed on the b.dload theory. Good agreement with experiments was achieved b. the present prediction of the Nikuradse roughness, erosion depth and sediment transport rate. Discussion was mainly focused on the prediction improvement caused b. considering the impact of suspended sediment and its damping to turb.lence.

关键词： mob.le plan b.d Nikuradse roughness oscillatory sheet flow sediment transport

EXPERIMENTAL AND THEORETICAL STUDY ON THE HIGH-SPEED HORIZONTAL WATER ENTRY b.HAVIORS OF CYLINDRICAL PROJECTILES

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Journal of Hydrodynamics 2012年第2期24卷 217-225页

作者： GUO zi-tao ZHANG Wei WANG Cong Hypervelocity Impact Research Center Harbin Institute of TechnologyHarbin 150080China

In this article,the horizontal water-entry of flat-nose projectiles of two different lengths at impact velocities of 400 m/s-600 m/s is studied experimentally and *** on the solution of the Rayleigh-b.sant prob.em,a set of projectile dynamic equations are derived and a cavity model is b.ilt to describ. the projectile＇s water entry dynamics.A parameter in the cavity model is determined b. employing the principle of energy *** results indicate that the flat-nose projectiles enjoy a good stab.lity of trajectory,the drag coefficient and the velocity decay coefficient are dependent on the cavitation numb.r,and increase along the penetration distance b.t with a relatively small *** maximum cavity radius decreases monotonically with the penetration *** with the same nose shapes at different initial velocities have a b.sically consistent cavity dimension b.fore the deep pinching off phenomenon *** agreements are ob.erved b.tween results ob.ained b. the analytical model and the experimental results.

关键词： horizontal water entry experiment theoretical analysis cavity dimension projectile dynamics