Synthesis and Crystal Structure of (S)-N-(2-oxoazepan-3-yl)biphenyl-4-carboxamide

The title compound(S)-N-(2-oxoazepan-3-yl)biphenyl-4-carboxamide(C19H20N2O2, Mr = 308.37) was synthesized by the reaction of(S)-α-amino-∑-caprolactam with 4-phenyl-benzoyl chloride. Its chemical structure was determined by 1H NMR, 13 C NMR, H RMS and X-ray single-crystal diffraction. The crystal belongs to the triclinic system, space group P1 with a = 8.2650(17), b = 13.774(3), c = 15.109(3) ?, β = 90.20(3)o, V = 1645.6(6) ?3, Z = 4, Dc = 1.245 g/cm3, μ = 0.081 mm-1, F(000) = 656, R = 0.0756 and w R = 0.1491 for 5964 observed reflections with I 2σ(I). The title compound was also used to prepare polyamide.     

Synthesis and Crystal Structure of（S）-N-（hexahydro-2-oxo-1H-azepin-3-yl）-3-phenyl-2-propenamide

The title compound(S)-N-(hexahydro-2-oxo-1H-azepin-3-yl)-3-phenyl-2-propenamide(C15H18N2O2, Mr = 258.31) was synthesized by the reaction of(S)-α-amino-ε-caprolactam with 3-phenyl-2- propenoyl chloride. Its chemical structure was determined by 1H NMR, 13C NMR, H RMS and X-ray single-crystal diffraction. The crystal belongs to the monoclinic system, space group P21/n with a = 14.957(3), b = 4.884(1), c = 18.630(4), β = 95.91(3)o, V = 1353.7(5)3, Z = 4, Dc = 1.267 g/cm3, μ = 0.085 mm-1, F(000) = 552, R = 0.0671 and wR = 0.1547 for 2473 observed reflections with I 2σ(I).     

基于Chebyshev-Taylor-Fourier混合级数模型函数的多源气动数据融合方法

针对飞行器气动力多源数据融合、飞行试验气动辨识问题,提出了一种基于Chebyshev-Taylor-Fourier混合级数模型函数、不确定度平衡权函数和加权最小二乘原理的多源数据融合和辨识方法.该方法采用二元Chebyshev级数、Taylor级数和Fourier级数技术建立飞行器气动模型函数,采用权函数技术平衡各数据源间的不同精度和不确定度,采用最小二乘法原理确定超定方程组解,从而获得Chebyshev-Taylor-Fourier混合级数模型函数的各项参数值,最终确定多源数据融合的飞行器气动力（力矩）系数模型函数数学表达式.典型的应用实例表明该方法高效实用、精度可靠,工程应用前景良好.      

Richards模型在蔬菜生长预测中的应用

本文从 Richards模型的数学表达出发 ,阐述了模型中各参数初始值的确定以及优化过程 .并利用菜花和菠菜的试验数据建立其“最优”生长模型 .     

证明(两)曲线对称的一种方法

要证明曲线ｃ：ｆ（ｘ,ｙ）＝０关于点Ｐ（或直线ｌ）对称,只需证明曲线ｃ关于点Ｐ（或直线ｌ）的对称曲线ｃ′就是ｃ;由曲线和方程的关系,只需证明ｃ′的方程就是ｃ的方程,即只需证明ｃ′的方程就是ｆ（ｘ,ｙ）＝０．要证明两曲线ｃ１：ｆ１（ｘ,ｙ）＝０与ｃ２：ｆ２（ｘ,ｙ）＝０关于点Ｐ（或直线ｌ）对称,只需证明曲线ｃ１关于点Ｐ（或直线ｌ）的对称曲线ｃ１′就是ｃ２;由曲线和方程的关系,只需证明ｃ１′的方程就是ｃ２的方程,即只需证明ｃ１′的方程就是ｆ２（ｘ,ｙ）＝０．我们把上面证明（两）曲线对称的方法叫同一法…     

Meshless analysis of an improved element-free Galerkin method for linear and nonlinear elliptic problems

We first give a stabilized improved moving least squares(IMLS) approximation, which has better computational stability and precision than the IMLS approximation. Then, analysis of the improved element-free Galerkin method is provided theoretically for both linear and nonlinear elliptic boundary value problems. Finally, numerical examples are given to verify the theoretical analysis.     

Rank-based deactivation model for networks with age

We study the impact of age on network evolution which couples addition of new nodes and deactivation of old ones. During evolution, each node experiences two stages: active and inactive. The transition from the active state to the inactive one is based on the rank of the node. In this paper, we adopt age as a criterion of ranking, and propose two deactivation models that generalize previous research. In model A, the older active node possesses the higher rank, whereas in model B, the younger active node takes the higher rank. We make a comparative study between the two models through the node-degree distribution.     

螺线管型爆磁压缩发生器快速计算模型

 根据等效电路模型,建立了单级螺线管型爆磁压缩发生器运行期间的电路方程,得到了回路电流表达式。采用0维电路模型计算电路参数,得到了电感和电阻计算公式。根据等效电路方程和电路参数计算公式,编写了一套计算编码,计算发生器充电过程和运行过程中发生器电路参数、内部电压、输出电流和能量、导线电导率和温度等参数的变化。与实验数据对比表明,该计算模型能准确预测单级螺线管型爆磁压缩发生器性能,对发生器的设计具有实际意义。     

二维瞬态热传导问题的无单元Galerkin法分析

采用无单元Galerkin(element-free Galerkin,EFG)法求解具有混合边界条件的二维瞬态热传导问题.首先采用二阶向后微分公式离散热传导方程的时间变量,将该问题转化为与时间无关的混合边值问题;然后采用罚函数法处理Dirichlet边界条件,建立了二维瞬态热传导问题的无单元Galerkin法;最后基于移动最小二乘近似的误差结果,详细推导了无单元Galerkin法求解二维瞬态热传导问题的误差估计公式.给出的数值算例表明计算结果与解析解或已有数值解吻合较好,该方法具有较高的计算精度和较好的收敛性.