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受δ(x)势微扰的一维无限深方势阱中粒子的能级与波函数 被引量:2
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作者 吴学勇 《喀什师范学院学报》 2003年第6期21-23,共3页
详细计算了δ(x)势微扰下一维无限深方势阱中粒子能级的一、二、三级和波函数的一、二级修正.
关键词 δ(x)势 一维无限深方势 波函数 粒子能级 量子力学 定态微扰论
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基于“四位一体”理论探讨半夏泻心汤治疗血管性痴呆 被引量:1
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作者 于金振 司国民 《山东中医药大学学报》 2023年第2期136-141,共6页
从“四位一体”理论入手,将“性、位、势、证”四要素作为分析经方的主要方向,以半夏泻心汤为例,结合中医经典及历代名家的学术观点,通过剖析半夏泻心汤的四要素,得出该方的“方性”为寒热并施、辛苦合用,并佐以甘调;“方位”为脾胃;“... 从“四位一体”理论入手,将“性、位、势、证”四要素作为分析经方的主要方向,以半夏泻心汤为例,结合中医经典及历代名家的学术观点,通过剖析半夏泻心汤的四要素,得出该方的“方性”为寒热并施、辛苦合用,并佐以甘调;“方位”为脾胃;“方势”为辛可向上,苦能降下,补泻兼施,配合守中;“方证”为中焦湿浊壅盛之痞。并以“四位一体”理论阐释半夏泻心汤对血管性痴呆的临床治疗,以期为经方的临床研究提供新思路。附医案1则。 展开更多
关键词 半夏泻心汤 血管性痴呆 四位一体 经方 方性 方位 方势 方证
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Effects of Different Cultivation Methods on Growth, Yield and Quality of Cassava 被引量:1
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作者 蒋万 吴勇 +2 位作者 江定 杨金辉 宋勇 《Agricultural Science & Technology》 CAS 2015年第10期2086-2090,共5页
The research explored effects of cultivation methods on growth, yield and quality of cassava. The results showed that the mulching treatment by direct seed- ing, the mulching treatment by transplanting, and the expose... The research explored effects of cultivation methods on growth, yield and quality of cassava. The results showed that the mulching treatment by direct seed- ing, the mulching treatment by transplanting, and the exposed treatment by trans- planting performed excellently in bringing seedling stage forward, improving germina- tion rate, yield and quality. For example, seedling emergence stages were 36, 31 and 31 d earlier; germination rates improved by 19.24%, 14.29% and 14.29%; yields grew by 41.98%, 26.72% and 11.45%; starch contents increased by 3.50%, 2.10% and 1.40%, respectively. Therefore, cassava in the mulching treatment by direct seeding is characterized by earlier seedling emergence stage, high germination rate, high yield and quality. 展开更多
关键词 CASSAVA Cultivation methods Growth vigor YIELD QUALITY
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Correlation between the Change in the Number of Apis mellifera Worker Bees and Nectar Secretion of Nectariferous Plants
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作者 余玉生 张祖芸 +2 位作者 宋文菲 卢焕仙 王艳辉 《Agricultural Science & Technology》 CAS 2014年第1期116-118,136,共4页
[Objective] This study aimed to clarify the correlation between changes of Apis mel ifera and the nectar secretion characteristics of nectariferous plants. [Method] Considering the nectar secretion characteristics of ... [Objective] This study aimed to clarify the correlation between changes of Apis mel ifera and the nectar secretion characteristics of nectariferous plants. [Method] Considering the nectar secretion characteristics of major and auxiliary nec-tariferous plants, six Apis mel ifera colonies were selected for measure the number of eggs, larvae, pupae and adult bees from Jan. to Dec. in 2012; based on that, their annual change curves were also plotted. [Result] The results showed that there were three peaks of the total number of A. mel ifera workers throughout the year:the first occurred on May 15th, with bees developed into an ideal population for col-lecting pomegranate nectar, and the second and third peaks occurred on July 15th and Oct. 15th, respectively, with bees developed into an ideal population for col ect-ing E. ciliate (Thuab) Hyland. [Conclusion] Prevention of Varroa jacobsoni should be carried out with two or more types of acaricides at the late nectar flow stages of the two nectariferous plants(pomegranate and E. ciliate (Thuab) Hyland) when there was a nectar deficiency. Prevention of Tropilaelaps clareae should be timely per-formed with sublimed sulfur in conjunction with acaricides. This study provides a theoretical basis for the high-quality and high-yielding production of honey, as wel as for the product safety. 展开更多
关键词 Apis mellifera Number of worker bees Nectariferous plants CURVE Theoretical basis
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Singular Solutions of the Cauchy Problem for SemilinearParabolic Equations with Singular Potentions
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作者 曾有栋 陈祖墀 《Chinese Quarterly Journal of Mathematics》 CSCD 2002年第1期1-8,共8页
In this paper we consider the Cauchy problem for the singular semilinear parabolic equation u t-Δu+V 1(x)u=V 2(x)u p,x∈R n\{0},t>0, where V 1(x),V 2(x) may have singularities at the origin. Using functions... In this paper we consider the Cauchy problem for the singular semilinear parabolic equation u t-Δu+V 1(x)u=V 2(x)u p,x∈R n\{0},t>0, where V 1(x),V 2(x) may have singularities at the origin. Using functions of the Kato class and the Green tight functions we got the existence of the positive solution being singular at the origin. 展开更多
关键词 SINGULARITY Kato class Green tight function fixed point
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Determination of Geopotential of Local Vertical Datum Surface 被引量:1
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作者 王晓妮 张洁 《Geo-Spatial Information Science》 2003年第1期1-4,共4页
This paper first develops the approaches to determine the geopotential of the local mean sea level,and then investigates the offset of the 1985 vertical datum surface defined by the mean sea level of Yellow Sea at the... This paper first develops the approaches to determine the geopotential of the local mean sea level,and then investigates the offset of the 1985 vertical datum surface defined by the mean sea level of Yellow Sea at the Dagang Tide Gauge in Qingdao city using the developed approaches and GPS/leveling data.It shows that the geopotential of the local mean sea level at the tide gauge is equal to 62 636 853.5±0.2 m2·s -2 and that the 1985 vertical datum surface is 24.6±5.4 cm above the geoid realized by the geopotential W 0= 62 636 856.0±0.5 m2·s -2. 展开更多
关键词 mean sea level the 1985 vertical datum GEOPOTENTIAL GPS/LEVELING
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国内低氧训练研究现状的可视化分析 被引量:1
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作者 李志刚 林文弢 《体育科研》 2018年第1期56-65,共10页
为了深入分析国内低氧训练研究的现状,运用CiteSpaceⅢ和CNKI的可视化功能对近20年来发表在国内体育核心期刊上有关低氧训练的文献进行计量学统计和可视化分析。结果表明,总体研究趋势以2008年为顶点呈正态分布,国内形成了凸显的科研力... 为了深入分析国内低氧训练研究的现状,运用CiteSpaceⅢ和CNKI的可视化功能对近20年来发表在国内体育核心期刊上有关低氧训练的文献进行计量学统计和可视化分析。结果表明,总体研究趋势以2008年为顶点呈正态分布,国内形成了凸显的科研力量。研究的热点主题包括低氧训练方式的多样化,低氧训练的监控,提高运动员的有氧和无氧能力,对机体的免疫力、认知功能的影响,在控重减肥中的应用,低氧训练干预下的氧化应激和细胞凋亡情况,低氧训练习服与基因多态性的关系,低氧训练对机体作用的分子机理的探讨等方面。新的低氧训练方式的应用、低氧训练的健康促进功能、低氧训练的分子机理的探讨和学科交叉成为今后的研究趋势。 展开更多
关键词 低氧训练 知识图谱 可视化 训练方式 研究热点 发展趋势
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Numerical modeling of the 2D time-domain transient electromagnetic secondary field of the line source of the current excitation 被引量:4
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作者 刘云 王绪本 王贇 《Applied Geophysics》 SCIE CSCD 2013年第2期134-144,235,共12页
To effectively minimize the electromagnetic field response in the total field solution, we propose a numerical modeling method for the two-dimensional (2D) time- domain transient electromagnetic secondary field of t... To effectively minimize the electromagnetic field response in the total field solution, we propose a numerical modeling method for the two-dimensional (2D) time- domain transient electromagnetic secondary field of the line source based on the DuFort- Frankel finite-difference method. In the proposed method, we included the treatment of the earth-air boundary conductivity, calculated the normalized partial derivative of the induced electromotive force (Emf), and determined the forward time step. By extending upward the earth-air interface to the air grid nodes and the zero-value boundary conditions, not only we have a method that is more efficient but also simpler than the total field solution. We computed and analyzed the homogeneous half-space model and the fiat layered model with high precision--the maximum relative error is less than 0.01% between our method and the analytical method--and the solution speed is roughly three times faster than the total-field solution. Lastly, we used the model of a thin body embedded in a homogeneous half-space at different delay times to depict the downward and upward spreading characteristics of the induced eddy current, and the physical interaction processes between the electromagnetic field and the underground low-resistivity body. 展开更多
关键词 Time-domain transient electromagnetics secondary field DuFort-Frankel finite-difference method numerical modeling.
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Quantum Dynamics Study on D+OD+ Reaction: Competition between Exchange and Abstraction Channels
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作者 许文武 张佩宇 何国钟 《Chinese Journal of Chemical Physics》 SCIE CAS CSCD 2013年第1期73-76,I0004,共5页
Quantum dynamics for the D+OD+ reaction at the collision energy range of 0.0-1.0 eV was studied on an accurate ab initio potential energy surface. Both of the endothermic abstraction (D+OD+-→O++D2) and thermo... Quantum dynamics for the D+OD+ reaction at the collision energy range of 0.0-1.0 eV was studied on an accurate ab initio potential energy surface. Both of the endothermic abstraction (D+OD+-→O++D2) and thermoneutral exchange (D+OD+--*D+OD+) channels were investigated from the same set of time-dependent quantum wave packets method under cen- trifugal sudden approximation. The reaction probability dependence with collision energy, the integral cross sections, and the thermal rate constant of the both channels are calculated. It is found that there is a convex structure in the reaction path of the exchange reaction. The calculated time evolution of the wave packet distribution at J=0 clearly indicates that the convex structure significantly influences the dynamics of the exchange and abstraction channels of title reaction. 展开更多
关键词 Time-dependent quantum wave packet method Potential energy surface D+OD+ reaction
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Solution of the Dirac Equation for Ring-Shaped Modified Kratzer Potential 被引量:3
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作者 CHENG Yan-Fu DAI Tong-Qing 《Communications in Theoretical Physics》 SCIE CAS CSCD 2007年第3X期431-434,共4页
We propose a new exactly solvable potential which is Formed by modified Kratzer potential plus a new ring-shaped potential η cot^2 θ/r^2 The solutions of the Dirac equation with equal scalar and vector ring-shaped m... We propose a new exactly solvable potential which is Formed by modified Kratzer potential plus a new ring-shaped potential η cot^2 θ/r^2 The solutions of the Dirac equation with equal scalar and vector ring-shaped modified Kratzer potential are found by using the Nikiforov-Uvarov method. The nonrelativistic limit of the energy spectrum has been discussed. 展开更多
关键词 Dirac equation SOLUTION ring-shaped modified Kratzer potential
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Innovative trend analysis of annual and seasonal precipitation in Ningxia,China 被引量:5
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作者 YANG Huiling XIAO Hui +2 位作者 GUO Chunwei SUN Yue GAO Ruina 《Atmospheric and Oceanic Science Letters》 CSCD 2020年第4期308-315,共8页
Based on daily rainfall data from 26 station records,spatial and temporal variations in annual and seasonal precipitation of different rainfall intensities from 1961 to 2018 in Ningxia,China are investigated using the... Based on daily rainfall data from 26 station records,spatial and temporal variations in annual and seasonal precipitation of different rainfall intensities from 1961 to 2018 in Ningxia,China are investigated using the innovative trend analysis(ITA)method.The results show that annual precipitation increases on the northern plain but decreases in the southern mountainous area.The increase in regional annual precipitation is mainly due to an increase in weak precipitation,while the decrease in regional annual rainfall is a result of a reduction in heavy precipitation.Lowintensity precipitation shows an upward trend,while high-intensity precipitation shows a downward trend.The variation trend of extreme precipitation is more obvious.The contributions of different types of extreme precipitation vary by season.During spring,the increase in regional rainfall is mainly caused by the increase in heavy precipitation,while the decrease in regional precipitation is mainly caused by the decrease in weak precipitation.During summer and autumn,the increase in regional precipitation is caused by the increase in light precipitation,while the reduction in regional rainfall is caused by the decrease in heavy precipitation.This study provides support for water resources planning and addressing droughts and floods. 展开更多
关键词 ITA PRECIPITATION trend analysis Ningxia
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A method for calculating the center position of collimated light 被引量:2
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作者 WU Guo-jun WU Ling-ling CANG Yu-ping HE Jun-hua DONG Wei-bin CHEN Liang-yi 《Optoelectronics Letters》 EI 2008年第2期155-158,共4页
It is a key problem to accurately calculate beam spots' center of measuring the warp by using a collimated laser. A new method, named double geometrical center method (DGCM), is put forward for the first time. In t... It is a key problem to accurately calculate beam spots' center of measuring the warp by using a collimated laser. A new method, named double geometrical center method (DGCM), is put forward for the first time. In this method, a plane wave perpendicularly irradiates an aperture stop, and a charge couple device (CCD) is employed to receive the diffraction-beam spots, then the geometrical centers of the fast and the second diffraction-beam spots are calculated respectively, and their mean value is regarded as the center of datum beam. In face of such adverse instances as laser intension distributing defectively, part of the image being saturated, this method can still work well. What's more, this method can detect whether an unacceptable error exits in the courses of image receiving, processing and calculating. The experimental results indicate the precision of this method is high. 展开更多
关键词 计算方法 位势 光学 激光
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New Exact Solutions and Conservation Laws to (3+1)-Dimensional Potential-YTSF Equation 被引量:10
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作者 ZHANG Li-Hua LIU Xi-Qiang 《Communications in Theoretical Physics》 SCIE CAS CSCD 2006年第3期487-492,共6页
Using the modified find some new exact solutions to Lie point symmetry groups and also get conservation laws, of the CK's direct method, we build the relationship between new solutions and old ones and the (3+1)-d... Using the modified find some new exact solutions to Lie point symmetry groups and also get conservation laws, of the CK's direct method, we build the relationship between new solutions and old ones and the (3+1)-dimensional potentiaial-YTSF equation. Baaed on the invariant group theory, Lie symmetries of the (3+1)-dimensional potential-YTSF equation are obtained. We equation with the given Lie symmetry. 展开更多
关键词 new exact solutions Lie point symmetry groups conservation laws (3+1)-dimensional potential-YTSF equation
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A Seasonal Prediction Model for the Summer Rainfall in Northeast China Using the Year-To-Year Increment Approach 被引量:8
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作者 ZHU Ya-Li 《Atmospheric and Oceanic Science Letters》 2011年第3期146-150,共5页
Using the year-to-year increment approach,this study investigated the relationship of selected climatic elements with the increment time series of the summer rainfall between successive years in Northeast China,includ... Using the year-to-year increment approach,this study investigated the relationship of selected climatic elements with the increment time series of the summer rainfall between successive years in Northeast China,including the soil moisture content,sea surface temperature,500 hPa geopotential height,and sea level pressure in the preceding spring for the period 1981-2008.Two spring predictors were used to construct the seasonal prediction model:the area mean soil moisture content in Northwest Eurasia and the 500 hPa geopotential height over Northeast China.Both the cross-validation and comparison with previous studies showed that the above two predictors have good predicting ability for the summer rainfall in Northeast China. 展开更多
关键词 Northeast China summer rainfall seasonalprediction year-to-year increment
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Research Approaches in Applied Linguistics
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作者 梁晶 《International English Education Research》 2014年第10期114-116,共3页
Research in applied linguistics, like research in other fields, is usually carried out by two approaches: quantitative approach and qualitative approach. It is agreed "both approach are needed, since no one methodol... Research in applied linguistics, like research in other fields, is usually carried out by two approaches: quantitative approach and qualitative approach. It is agreed "both approach are needed, since no one methodology can answer all questions and provide insights on all issues". The two approaches follow different procedures and inevitably have respective advantages and drawbacks. Three general types of quantitative methods are experiments, quasi-experiments and surveys. Three general types of methods concerning qualitative approach used in linguistics are case study, action research and ethnographic research. Different types of research questions can be studied through various research methods. It is important to recognise the distinction between quantitative approach and qualitative approaches. It is up to the researcher to choose the specific approach in accordance with the suitability of the method for the particular research. It can be a single approach, or combination of the two, providing it allows maximal reliability and validity of the study. 展开更多
关键词 quantitative approach qualitative approach advantages LIMITATIONS
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China cardiovascular diseases report 2015: a summary 被引量:50
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作者 Wei-Wei CHEN Run-Lin GAO +10 位作者 Li-Sheng LIU Man-Lu ZHU Wen WANG Yong-Jun WANG Zhao-Su WU Hui-Jun LI Dong-Feng GU Yue-Jin YANG Zhe ZHENG Li-Xin JIANG Sheng-Shou HU 《Journal of Geriatric Cardiology》 SCIE CAS CSCD 2017年第1期1-10,共10页
1 Introduction Major and profound changes have taken place in China over the past 30 years. An epidemic of cardiovascular diseases (CVD) in China is emerging as a result of lifestyle changes, urbanization, and the ... 1 Introduction Major and profound changes have taken place in China over the past 30 years. An epidemic of cardiovascular diseases (CVD) in China is emerging as a result of lifestyle changes, urbanization, and the accelerated process of aging. The incidence of CVD is continuously increasing and will remain an upward trend in the next decade. Since 2005, 展开更多
关键词 Atrial fibrillation Cardiovascular diseases HYPERTENSION Risk factors STATISTICS STROKE
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Theoretical Research on Scattering Resonance States of Reaction I+HI(v=O)→IH(v'=0)+I: Partial Potential Energy Surface and One-dimensional Quantum Reactive Scattering Calculation
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作者 Hua-yang Wang Xiao-min Sun +1 位作者 Zheng-ting Cai Da-cheng Feng 《Chinese Journal of Chemical Physics》 SCIE CAS CSCD 北大核心 2006年第5期411-415,共5页
Based on the vibrational potential curves coupled with the minimum energy reaction path, the partial potential energy surface of the reaction I+HI→IH+I was constructed at the QCISD(T)//MP4SDQ level with pseudo po... Based on the vibrational potential curves coupled with the minimum energy reaction path, the partial potential energy surface of the reaction I+HI→IH+I was constructed at the QCISD(T)//MP4SDQ level with pseudo potential method. And the formation mechanism of the scattering resonance states of this reaction was well interpreted with the partial potential energy surface. The scattering resonance states of this reaction should belong to Feshbach resonance because of the coupling of the vibrational mode and the translational mode. With the one-dimensional square potential well model, the resonance width and lifetime of the I+HI(v=0)→IH(v'=0)+I state-to-state reaction were calculated, which preferably explained the high-resolved threshold photodetachment spectroscopy of the IHI- anion performed by Neumark et al.. 展开更多
关键词 Partial potential energy surface Scattering resonance states Scattering resonance width and lifetime One-dimensional square potential well model
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Periodic Structures of Rossby Wave under Influence of Dissipation 被引量:2
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作者 CHEN Zhe LI Chong-Yin FU Zun-Tao 《Communications in Theoretical Physics》 SCIE CAS CSCD 2007年第1期35-40,共6页
A simple barotropic potential vorticity equation with the influence of dissipation is applied to investigate the nonlinear Rossby wave in a shear flow in the tropical atmophere. By the reduetive perturbation method, w... A simple barotropic potential vorticity equation with the influence of dissipation is applied to investigate the nonlinear Rossby wave in a shear flow in the tropical atmophere. By the reduetive perturbation method, we derive the rotational KdV (rKdV for short) equation. And then, with the help of Jaeobi elliptie functions, we obtain various periodic structures for these Rossby waves. It is shown that dissipation is very important for these periodic structures of rational form. 展开更多
关键词 rKdV equation elliptic equation Jacobi elliptic function periodic structure rational form
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Edge detection using directional eigenvalues of potential field gradient tensor data 被引量:2
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作者 ZHOU Shuai HUANG Danian 《Global Geology》 2015年第3期188-195,共8页
Edge detection of potential field interpretation is an important task. The traditional edge detection methods have poor ability in outlining weak amplitude anomalies clearly. The resolved edges position is blurred.We ... Edge detection of potential field interpretation is an important task. The traditional edge detection methods have poor ability in outlining weak amplitude anomalies clearly. The resolved edges position is blurred.We purposed new edge detection methods based on directional eigenvalues of potential field gradient tensor for the causative sources. In order to balance strong and weak amplitude anomalies simultaneously,we present one normalization method using different orders of vertical derivatives to improve the new filters. The presented filters were tested on synthetic and real potential field data to verify its feasibility. All of the results have shown that the new edge detection methods can not only display the sources edges precisely and clearly,but also bring out more geological subtle details. 展开更多
关键词 directional eigenvalues edge detection potential field
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A Note on Similarity Reductions of Barotropic and Quasi-geostrophic Potential Vorticity Equation
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作者 TANG Xiao-Yan Padma Kant Shukla 《Communications in Theoretical Physics》 SCIE CAS CSCD 2008年第1期229-230,共2页
Applying the classical Lie symmetry approach to the barotropic and quasi-geostrophic potential vorticity equation without forcing and dissipation on a β-plane channel, we find a new symmetry, which is not presented i... Applying the classical Lie symmetry approach to the barotropic and quasi-geostrophic potential vorticity equation without forcing and dissipation on a β-plane channel, we find a new symmetry, which is not presented in a previous work [F. Huang, Commun. Theor. Phys. (Beijing, China) 42 (2004) 903]. A general finite transformation group is obtained based on the full Lie point symmetry, Furthermore, two new types of similarity reduction solutions are obtained. 展开更多
关键词 Lie symmetry similarity reductions potential vorticity equation
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