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On the horizontal distribution of algal-bloom in Chaohu Lake and its formation process 被引量:7
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作者 Yuan-Ying Chen Qing-Quan Liu 《Acta Mechanica Sinica》 SCIE EI CAS CSCD 2014年第5期656-666,共11页
Based on the remote sensing images of algae, the present work analyzes the horizontal distribution characteristics of algal blooms in Chaohu Lake, China, which also reveals the frequency of algal blooms under differen... Based on the remote sensing images of algae, the present work analyzes the horizontal distribution characteristics of algal blooms in Chaohu Lake, China, which also reveals the frequency of algal blooms under different wind directions. Further, an unstructured-grid, three-dimensional finite-volume coastal ocean model (FVCOM) is applied to investigate the wind-induced currents and the transport pro- cess to explain the reason why algal blooms occur at the detected places. We first deduce the primary distribution of biomass from overlaid satellite images, and explain the formation mechanism by analyzing the pollution sources, and simulating the flow field and transportation process under prevailing wind over Chaohu Lake. And then, we consider the adjustment action of the wind on the corresponding day and develop a two-time scale approach to describe the whole formation process of algae horizontal distribution in Chaohu Lake. That is, on the longer time scale, i.e., during bloom season, prevailing wind determines the primary distribution of biomass by inducing the characteristic flow field; on the shorter time scale, i.e., on the day when bloom occurs, the wind force adjusts the primary distribution of biomass to form the final distribution of algal bloom. 展开更多
关键词 Chaohu Lake Algal bloom Horizontal distri- bution - Wind-driven current Two-time scale process
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Origin of diffraction fringes in two-dimensional photoelectron momentum distributions for single ionization of atoms in few-cycle intense laser pulses 被引量:4
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作者 郭志坚 陈长进 周效信 《Chinese Physics B》 SCIE EI CAS CSCD 2014年第4期223-229,共7页
We use the strong field approximation with a time window function controlling the release time of electrons to study the intra-cycle and inter-cycle interferences in few-cycle intense laser pulses impinging on He. The... We use the strong field approximation with a time window function controlling the release time of electrons to study the intra-cycle and inter-cycle interferences in few-cycle intense laser pulses impinging on He. The diffraction fringes, i.e., the vertical stripe-like structure, observed in the experimental two-dimensional photoelectron momentum distributions of Gopal et al. (2009 Phys. Rev. Lett. 103 053001) have been attributed to the interplay of the intra- and inter-cycle interferences. The pure numerical calculations by solving the time-dependent Schrrdinger equation are also performed and the results are compared with the experimental measurements directly. It has been found that the position of the stripe-like structure can be used to determine the duration of the laser pulses used in experiments. 展开更多
关键词 intra-cycle and inter-cycle interferences stripe-like structure two-dimensional momentum distri- butions
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汉语同素逆序物象词初探 被引量:1
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作者 吴汉江 《常熟理工学院学报》 2014年第5期85-90,共6页
汉语同素逆序物象词是一种值得关注的词汇类聚现象。从词义类型上看,同素逆序物象词分为词义完全相同、词义不完全相同两种;从语法结构上看,主要有偏正式、联合式两类;从年代分布上看,有些产生于大致相同的年代,有些产生于相隔较远的不... 汉语同素逆序物象词是一种值得关注的词汇类聚现象。从词义类型上看,同素逆序物象词分为词义完全相同、词义不完全相同两种;从语法结构上看,主要有偏正式、联合式两类;从年代分布上看,有些产生于大致相同的年代,有些产生于相隔较远的不同年代。 展开更多
关键词 同素逆序物象词 词义类型 语法结构 年代分布
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广义极值分布在重庆短历时极值降水中的应用 被引量:10
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作者 王颖 刘晓冉 +2 位作者 程炳岩 孙佳 廖代强 《气象》 CSCD 北大核心 2019年第6期820-830,共11页
利用广义极值分布函数拟合1981—2016年重庆34个国家气象站短历时(1、3、6、12h)极值降水序列,对拟合结果进行显著性水平检验,并给出不同重现期极值降水的空间分布。结果表明:广义极值分布函数能较好地拟合重庆地区的短历时极值降水。... 利用广义极值分布函数拟合1981—2016年重庆34个国家气象站短历时(1、3、6、12h)极值降水序列,对拟合结果进行显著性水平检验,并给出不同重现期极值降水的空间分布。结果表明:广义极值分布函数能较好地拟合重庆地区的短历时极值降水。随着降水历时的延长,服从Weibull分布(Frechet分布)的站点数逐渐减少(增加)。各短历时不同重现期降水的空间分布具体表现为10a以下及20a以上基本相似,位于长江沿线以北的重庆西北部地区降水量明显大于重庆长江沿线以南地区,且渝东南降水的相对大值区位于彭水地区。随着重现期的增加,降水中心更加集中,渝东北的大值中心随着历时的延长向北移动。广义极值分布函数的形状参数的绝对值接近或超出0.5时,计算的高重现期(大于样本长度)极值降水存在较大偏差;当不同历时降水拟合的形状参数值具有明显差异时,高重现期降水可能出现与客观规律相悖的现象。 展开更多
关键词 短历时降水 年最大值取样 广义极值分布 重现期降水
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TWO-DIMENSIONAL MATHEMATICAL MODEL OF COMBUSTION SPACE IN GLASS MELTING FURNACES
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作者 吴锡琪 李立华 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS 1994年第2期50-58,共9页
Under some assumptions and dividing the combustion space into several isothermal zones and isothermal surface elements, a two-dimensional mathematical model for combustion space in cross-fired glass melting furnaces w... Under some assumptions and dividing the combustion space into several isothermal zones and isothermal surface elements, a two-dimensional mathematical model for combustion space in cross-fired glass melting furnaces was constructed. The finite element method and the Gauss integration were used to calculate direct ex-change areas, and a inverse matrix was used to obtained the total ex-change areas. The temperature distributions were obtained by itera-tions. Some results were presented to show the effects of the fire tem-perature distribution, the convective -heat transfer coefficients and the heat losses through crown surfaces on the temperature distributions. 展开更多
关键词 glass melting furnace fire space temperature distri- bution finite element method
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Particle size distribution and shape control of Au nanoparticles used for particle gun 被引量:1
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作者 S. Kida M. Ichiji J. Watanabe I. Hirasawa 《Frontiers of Chemical Science and Engineering》 SCIE EI CAS CSCD 2013年第1期60-64,共5页
Au nanoparticles are expected for the media to transfer genes into plants. However, the control of particle size distribution (PSD) and shape of Au nanoparticles is too difficult to design and prepare particles with... Au nanoparticles are expected for the media to transfer genes into plants. However, the control of particle size distribution (PSD) and shape of Au nanoparticles is too difficult to design and prepare particles with suitable quality for the gene supporting media. Reduction crystal- lization experiments were performed in aqueous solution in order to clarify the effect of feeding conditions such as feeding profile, feeding rate, and feeding amount on PSD and shape of Au nanopartieles. Ascorbic acid (AsA) was selected as a reducing agent because it is safe for plants. Au particles of 50nm, 50-200nm, and 150-400nm were obtained in batch operation, single-jet, and double-jet, respectively. Moreover, in single-jet and double-jet, the mean size of the obtained Au particles increases with the decrease of feeding rate or the increase of feeding amount. It is concluded that PSD of Au nanoparticles can be controlled in the range of 50-400 nm by changing feeding conditions of AsA and HAuCl4 aqueous solution. 展开更多
关键词 reduction crystallization particle size distri- bution gene transferring media
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Uniqueness of Cycle Length Distributions of Certain Bipartite Graphs K_(n,n+7)-A(|A| ≤ 3)
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作者 朱建明 喻文华 沙丹 《Journal of Mathematical Research and Exposition》 CSCD 北大核心 2008年第4期813-822,共10页
The cycle length distribution of a graph of order n is denoted by (c1,c2,...,cn), where ci is the number of cycles of length i. In this paper, we obtain that a graph G is uniquely determined by its cycle distribution ... The cycle length distribution of a graph of order n is denoted by (c1,c2,...,cn), where ci is the number of cycles of length i. In this paper, we obtain that a graph G is uniquely determined by its cycle distribution if: (1) G = Kn,n+7 (n ≥ 10); or (2) G = Kn,n+7 - A (|A| = 1,n ≥ 12); or (3) G = Kn,n+7 - A (|A| = 2,n ≥ 14); or (4) G = Kn,n+7 - (|A| = 3,n ≥ 16), where A - E(Kn,n+7). 展开更多
关键词 CYCLE cycle length distribution bipartite graph uniqueness of cycle length distri- bution.
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Meromorphic Solutions of Systems of Higher-Order Algebraic Differential Equations in Complex Domain 被引量:1
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作者 高凌云 《Journal of Mathematical Research and Exposition》 CSCD 北大核心 2001年第2期171-176,共6页
Using the Nevanlinna theory of the value distribution of meromorphic func- tions,we investigate the problem of the existence of admissible meromorphic solutions of a type of systems of higher-order algebraic different... Using the Nevanlinna theory of the value distribution of meromorphic func- tions,we investigate the problem of the existence of admissible meromorphic solutions of a type of systems of higher-order algebraic differential equations. 展开更多
关键词 meromorphic solutions systems of differential equations the value distri- bution.
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