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51.
采用傅里叶变换红外光谱(FTIR)及其二阶导数谱对不同生长年限当归药材进行分析研究.结果表明,不同生长年限当归药材的红外图谱较为相似,仅从一维谱图上无法反映出不同生长年限当归药材的红外特征谱明显的异同,但通过二阶导数图谱中1771、1747、1712、1559、1514、1466、766、711cm-1和668cm-1处的峰型差异可发现不同生长年限当归药材之间的一些成分存在较明显的差异.由于生长时间不同,导致它们的化学成分存在差异,所以体现了各自的红外特征谱,其中第三年当归药材与第一年和第二年当归药材间差异较大. 相似文献
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Considering in symmetrical half-length bond operations,we present in this paper two types of newlydeveloped generalizations of the remarkable Migdal-Kadanoff bond-moving renormalization group transformation recursion procedures.The predominance in application of these generalized procedures are illustrated by making use of them to study the critical behavior of the spin-continuous Gaussian model constructed on the typical translational invariant lattices and fractals respectively.Results such as the correlation length critical exponents obtained by these means are found to be in good conformity with the classical results from other previous studies. 相似文献
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ZOU Jian CAI Jin-Fang SHAO Bin LI Qian-Shu 《理论物理通讯》2005,44(2):259-268
We study the interaction between a single-mode quantized field and a quantum system composed of two qubits. We suppose that two qubits initially be prepared in the mixed and separable state, and study how entanglement between two qubits arises in the course of evolution according to the Jaynes-Cummings type interaction with nonclassical radiation field. We also investigate the relation between entanglement and purity of qubit subsystem. We show that different photon statistics have different effects on the dynamical behavior of the qubit subsystem. When the qubits are initially prepared in the maximally mixed and separable state, for coherent state field we cannot find entanglement between two qubits; for squeezed state field entanglement between two qubits exists in several short period of time; for even and odd coherent state fields of large photon number, the dynamical behavior of the entanglement between two qubits shows collapse and revival phenomenon. For odd coherent state field of small photon number, the entanglement with both qubits initially prepared in maximally mixed state can be stronger than that with both qubits initially prepared in pure states. For fields of small photon number, the entanglement strongly depends on the states they are initially prepared in. For coherent state field, and odd and even coherent state fields of large photon number, the entanglement only depends on the purity of the initial state of qubit subsystem. We also show that during the evolution the unentangled state may be purer than the entangled state, and the maximum degree of entanglement may not occur at the time when the qubit subsystem is in the purist state. 相似文献
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Potential energy curves (PECs) of the ground and the low-lying excited states of the InI molecule are computed using the internally contracted multireference singles and doubles configuration interaction with the Davidson correction (ic-MR-CISD + Q) method based on the relativistic effective core potentials (RECPs). The spectroscopic constants are obtained, including the excitation energy (T e), the equilibrium bond distance (R e), the dipole moment (μe) and the vibrational constants (ωe and ωe). Finally, we predict the transition dipole moments, the radiative lifetimes, and the Franc-Condon factors for the transitions of A3Π0+ ? X1Σ0 + and B3Πl ? X1Σ0 +,. The results reveal that A3Π0+ and B3Πl are long-lived states with the lifetimes being of the order of microseconds. 相似文献
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Recently BESⅡ collaboration observed an enhancement near the pp invariant mass spectrum. Using the covariant tensor formalism, here we provide theoretical formulae for the partial wave analysis (PWA) of the ψ radiative decay channels ψ→γpp, γΛΛ, γ∑∑,γΞΞ. By performing the Monte Carlo simulation, we give the angular distributions for the photon and proton in the process of J/ψ→γ pp, which may serve as a useful reference for the future PWA on these channels. 相似文献
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基于连续介质假设,根据无吸收各向同性弹性介质通用方程分析沉积物声波传播关系,提出应用弹性结构分布因子表达的声速通用模型(GMSS,General Model of Sound Speed)分析海底沉积物的声速特性;通过研究Willey时间平均模型、Wood方程、Gassmann方程、Buckingham模型、Biot-Stoll模型和EDFM模型,可以表述成GMSS通用模型中的弹性结构分布因子的具体表达形式,得出GMSS通用模型在解释压缩波速度和切变波速度特性上具有一致性的特点。GMSS通用模型具有弹性结构分布因子、孔隙度、孔隙海水的等效密度和等效弹性模量、固相颗粒的等效密度、固相颗粒的等效体积弹性模量和等效切变弹性模量共7个参数,为研究海底沉积物压缩波和切变波速度提供了一种模型简单、参数少、通用性强的方法。但也需要从物理结构上以及应力应变关系上开展更为深入的分析和探寻GMSS模型的物理意义和参数测量的方法。 相似文献
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