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91.
D. Madhavi LathaV.G.K.M. Pisipati C. Rama Chandra PrabhuP.V. Datta Prasad 《Journal of Molecular Liquids》2011,164(3):187-190
The thermodynamic parameters like Moelwyn-Hughes parameter (C1), reduced molar volume (V~), isochoric temperature coefficient of internal pressure (X), Huggin's parameter (F), Gruneisen parameter (Γp), isothermal microscopic Gruneisen parameter, Sharma parameter (So), fraction free volume (f) and (A?) a dimensionless thermal parameter, etc and the Beyer's nonlinearity parameter (B/A) were deduced employing the thermal expansion coefficient derived from density data for the homologues series of compounds terephthalyidene-bis-p-n-alkyl anilines, TBnA with n = 5 to 10,12,14,16 and 18. Further, it is found that the variation of molecular radius, Mr increases with the increase of alkyl chain number, with a core radius of 4.78 Å and the increment for methylene unit is 0.086 Å . The results were discussed with the body of the data available. 相似文献
92.
A new method for constructing a Hamiltonian for configuration interaction calculations with constraints to energies of spherical configurations obtained with energy-density-functional (EDF) methods is presented. This results in a unified model that reproduced the EDF binding-energy in the limit of single-Slater determinants, but can also be used for obtaining energy spectra and correlation energies with renormalized nucleon–nucleon interactions. The three-body and/or density-dependent terms that are necessary for good nuclear saturation properties are contained in the EDF. Applications to binding-energies and spectra of nuclei in the region above 208Pb are given. 相似文献
93.
随着城市铁路系统的快速发展,铁路沿线建筑内人群对地铁运行产生噪声的抱怨逐渐增多,为控制室内地铁噪声对人群所产生的负面影响,有必要对地铁噪声产生的多维度负面情绪进行评估。采集了79名受试者对建筑内地铁噪声的多维度负面感受(压抑感,不舒适度和不满意度),基于偏最小二乘法分析了主客观影响因素对多维度负面感受的作用机制,并比较了多维度负面感受在反映地铁噪声影响上的差异。结果表明,多维度负面感受主要取决于主观响度和声学参数,活动干扰度、地铁噪声的敏感度、厌烦度和适应性的影响明显更弱;3个多维度负面感受中,相比于压抑感,不舒适度和不满意度受主观响度的影响轻微更显著,在相同的主观响度感受下,不满意度等级最高。 该文可以为地铁沿线建筑物内噪声负面感受的评价和改善提供参考。 相似文献
94.
针对垂直水声通信中时变多普勒引起的定时偏差问题,研究一种基于伪随机序列的迭代定时估计及补偿算法。该方法利用伪随机序列作为同步信号,分三步估计时变多普勒:采用低复杂度的模糊函数法粗补偿接收信号内的平均多普勒;通过迭代插值法实现残留时变多普勒的精确估计及补偿;利用基于信道相关函数的相位信息,纠正均衡后信号的偏转相位。为实现高阶海试数据的有效解调,采用基于伪随机序列均方误差的多通道加权合并方式,获得空间分集增益。仿真及海试数据处理结果证明所提方法具有良好的时变多普勒估计及补偿性能,同时对30个通道内的1024QAM数据进行合并处理,在500 m的通信距离下,误码率为0.04,信道容量达到7.6 bits/symbol。与传统数据帧结构相比,无需使用线性调频信号,可以提高有效数据传输率。 相似文献
95.
在建立水平井流动方程的基础上,通过气固两相流动基本数学模型的求解数值模拟不同工况条件下的气固混合物冲蚀能量,得出了冲蚀能量的变化规律。算例数值模拟显示:环空速度剖面主要由注气量大小决定,机械钻速的影响不大;相同注气量条件下,机械钻速降低与井下岩屑浓度等比例下降;注气量的增加能提高井眼净化程度,但不如降低机械钻速效果明显;环空总冲蚀能中气体冲蚀能量占绝对主要地位,岩屑冲蚀能量只占极小部分,在相同注气量条件下总冲蚀能量基本相同;岩屑冲蚀能量主要取决于机械钻速,机械钻速越大井底产生岩屑越多冲蚀能力越强,相同机械钻速条件下,较大注气量能提供较大岩屑运移速度,提高了岩屑冲蚀能量。 相似文献
96.
B. Rousselet 《基于设计的结构力学与机械力学》2013,41(3):353-358
This paper provides a new proof of design sensitivity of the static response of some typical structures. These structures (beams, plates, and plane elastic solids) have been described previously. A proof of design sensitivity of the inverse state operator was provided there, and design sensitivity of static response was derived. The proof presented here is simpler and self-contained. 相似文献
97.
M. I. Épov V. I. Pen'kovskii N. K. Korsakova I. N. Yeltsov 《Journal of Applied Mechanics and Technical Physics》2003,44(6):796-802
A new method is proposed for processing the data of electromagnetic logging in wells. The method is based on the hydrodynamic analysis of drilling mud filtrate penetration into the oil stratum, determination of the field of electrical resistances of the near-well zone with its subsequent averaging by convolutions with a kernel in the form of a logarithmically normal distribution of probe sensitivity. 相似文献
98.
99.
The acoustic wave equation is here discretized by conforming spectral elements in space and by the second order leap-frog
method in time. For simplicity, homogeneous boundary conditions are considered. A stability analysis of the resulting method
is presented, providing an upper bound for the allowed time step that is proportional to the size of the elements and inversely
proportional to the square of their polynomial degree. A convergence analysis is also presented, showing that the convergence
error decreases when the time step or the size of the elements decrease or when the polynomial degree increases. Several numerical
results illustrating these results are presented.
Mathematics subject classifications (2000) 65M06, 65M70, 65M12
This work was supported by MIUR (PRIN 2001 “Metodi numerici avanzati per equazioni alle derivate parziali di interesse applicativo”). 相似文献
100.
Amplitude and phase of high frequency surface acoustic wave (SAW) fields are investigated by a novel scanning tunneling microscopy technique. The gap voltage is modulated at a slightly detuned high frequency. Due to the nonlinearity of the tunneling process a frequency mixing appears. For scanned areas with dimensions much smaller than the wavelength of the SAW a remarkable local variation of amplitude and phase of the tunneling current at the difference frequency is observed. Depending on the local morphology different components of the particle displacement vector are detected. Model calculations of amplitude and phase images are presented for a real topography. 相似文献