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851.
Novel correction method for X-ray beam energy fluctuation of high energy DR system with a linear detector 总被引:1,自引:0,他引:1
A high energy digital radiography (DR) testing system has generated diverse scientific and technological interest in the field of industrial non-destructive testing. However, due to the limitations of manufacturing technology for accelerators, an energy fluctuation of the X-ray beam exists and leads to bright and dark streak artifacts in the DR image. Here we report the utilization of a new software-based method to correct the fluctuation artifacts. The correction method is performed using a high pass filtering operation to extract the high frequency information that reflects the X-ray beam energy fluctuation, and then subtracting it from the original image. Our experimental results show that this method is able to rule out the artifacts effectively and is readily implemented on a practical scanning system. 相似文献
852.
853.
介绍了能量色散X荧光分析方法在含水Fe样品测量中的应用.用ANTG -2000型海底X荧光探测系统对含Fe为10%~60%的Fe样进行测量,建立水分对Fe元素特征K α射线影响的校正模型.结果表明,通过该模型校正,对含饱和水情况下Fe样品的分析相对误差小于4%,具有良好的分析效果. 相似文献
854.
详细地介绍了辉光放电质谱分析中的质谱干扰如同量异位素、多原子离子和多电荷离子干扰。从同位素选择、高分辨率仪器、碰撞诱导解离、离子源冷却、数学方法校正、放电气体更换和放电气体纯度提高等方面对辉光放电质谱的质谱干扰校正方法的现状进行了评述(引用文献共68篇)。 相似文献
855.
The "International Workshop on e+e- collisions from phi to psi" (PHIPSI09), was held at Institute of High Energy Physics (IHEP), Chinese Academy of Sciences (CAS), Beijing, China, from Tuesday, October 13 to Friday, October 16 2009. This is the seventh workshop in a series, which started in Karlsruhe in 1996 and continued in Novosibirsk (1999), SLAC (2001), Pisa (2003), Novosibirsk (2006), and Frascati (2008), 相似文献
856.
A weakly nonlinear model is proposed for the Kelvin-Helmholtz instability in two-dimensional incompressible fluids by expanding the perturbation velocity potential to third order. The third-order harmonic generation effects of single-mode perturbation are analyzed, as well as the nonlinear correction to the exponential growth of the fundamental modulation. The weakly nonlinear results are supported by numerical simulations. Density and resonance effects exist in the development of mode coupling. 相似文献
857.
858.
本文从分析电子自旋磁矩(磁极)的空间性质入手,讨论了电子的可区分性.通过讨论2个电子自旋组态的8种形式,其中,包括4种磁极吸引的耦合态、4种磁矩排斥的非耦合态,同理,电子轨旋运动也存在4种耦合态.自旋耦合、轨旋全耦合需要8个电子,所以元素周期性为8音律.磁矩耦合是形成化学键的第一要求,第二才是异核吸引作用;化学键的广义表达语言应该是:化学键只能由磁矩耦合的电子组成.对电子的波粒二象性和测不准原理进行了新的理论解释,并讨论了波粒二象性和测不准现象的物理模型.该模型与电子的微观可区分性相一致. 相似文献
859.
The significant modifications to our recently constructed electron momentum spectrometer have been implemented. Compared with our previous report, the energy and the angle resolutions are significantly improved and reach △E = 0.45 eV, △θ = ±0.53° and △φ = ±0.84°, respectively. Moreover, the details of data reduction and the relation between azimuthal angle range and the sensitivity are discussed. 相似文献
860.
The effect of configuration complex on dielectronic recombination process in highly ionized plasmas 下载免费PDF全文
This paper analyses the effect of configuration complex on dielectronic recombination (DR) process in highly ionized plasmas (Xe^26+, Dy^38+, W^46+) by using the multiconfiguration relativistic Hartree-Fock method. Resonant and nonresonant radiative stabilizing transitions and decays to autoionizing levels followed by radiative cascades are included. Collisional transitions following electron capture are neglected. The remarkable difference between the isoelectronic trend of the rate coefficients for DR through 3d^94l4l′ and through 3d^94l5l′ is emphasized. The trend of DR through 3d^94l4l′ shows irregularities at relatively low temperature due to the progressive closing of DR channels as atomic number Z increases. 相似文献