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991.
K. Ram Narayana B. Seetharamireddy V. Koteswararao S. Abdul Sattar M.V.R. Murti L.S. Mombasawala 《X射线光谱测定》2018,47(2):127-136
K α X‐ray satellite spectra of Co, Ni, Cu, Zn, and Ga generated by photon excitation are analyzed using a wavelength dispersion spectrometer. Spectra of Ni, Cu, Zn, and Ga are studied for the first time using a LiF420 crystal. Spectrum of Co was studied with LiF200 crystal in second order. KαL1 X‐ray satellite energies and relative intensities are measured. The energy shifts relative to diagram line are computed and are compared with theoretical and semi‐empirical values. Dependence of energy shifts and relative intensities on Z and mode of excitation is analyzed. 相似文献
992.
Perovskite solar cell is a kind of revolutionary investigation in the field of renewable energy which is capable of mitigates the deficiencies of silicon solar cell and its uprising efficiency can bring blessing to society. The presence of lead (Pb) in perovskite solar cell can make worst and negative impact on environment and is not desirable for our society. In this paper, general plans are anticipated by replacement of Pb with tin (Sn) in open atmosphere to fabricate the CH3NH3SnCl3 photovoltaic cells in chlorine (Cl)-rich environment. Excess uses of Cl has positive influences on morphological growth of the film and it also suppresses the oxidation tendency of tin (Sn) with existing oxygen in atmosphere and maintains same chemical atmosphere as bulk. Various characterization tools like X-ray diffraction, scanning electron microscope (SEM) have been used to study the effect of annealing temperature on crystal stricture, phase formation, impurities, and morphologies of the film. Finally, photovoltaic performance was reported using the solar simulator under 1.5 sun illumination. 相似文献
993.
Video images of laser beams imprinted with distinguishable features are used for alignment of 192 laser beams at the National Ignition Facility (NIF). Algorithms for determining the position of these beams enable control systems to perform the task of alignment. Real world beam images suffer from intensity fluctuation or other distortions, making algorithms susceptible to higher position measurement variability. Using matched filtering to identify beam positions results in greater stability of position measurement compared to centroiding techniques. However, this gain is achieved at the expense of extra processing time. This work explores the use of FPGAs to accelerate these computations. Results indicate a performance improvement of 20 times for an FPGA over a 3 GHz Pentium 4 processor. 相似文献
994.
Laser cutting of thick sheet metals: Residual stress analysis 总被引:1,自引:0,他引:1
Laser cutting of tailored blanks from a thick mild steel sheet is considered. Temperature and stress field in the cutting sections are modeled using the finite element method. The residual stress developed in the cutting section is determined using the X-ray diffraction (XRD) technique and is compared with the predictions. The structural and morphological changes in the cut section are examined using the optical microscopy and scanning electron microscopy (SEM). It is found that temperature and von Mises stress increase sharply in the cutting section, particularly in the direction normal to the cutting direction. The residual stress remains high in the region close to the cutting section. 相似文献
995.
V. A. Abdul’yanov L. F. Galiullina A. S. Galyavich V. G. Izotov G. V. Mamin S. B. Orlinskii A. A. Rodionov M. Kh. Salakhov N. I. Silkin L. M. Sitdikova R. N. Khairullin Yu. A. Chelyshev 《JETP Letters》2008,88(1):69-73
New possibilities of applying high-frequency electron paramagnetic resonance in medicine are demonstrated on an example of the investigation of a calcified atherosclerotic plaque. After the irradiation of the atherosclerotic plaque by x rays, a new type of paramagnetic centers—organomineral radicals—is detected. The spectral and relaxation characteristics of these radicals depend on the calcification degree of the atherosclerotic plaque and can be used for diagnostics. 相似文献
996.
997.
C. D. O'Shaughnessy Abdul Hoque D. C. Frank Hee Tang Ooi 《Annals of the Institute of Statistical Mathematics》1983,35(1):453-459
Summary The polytopal association scheme for PBIB designs is introduced and studied utilizing the concept of clustering of treatments. 相似文献
998.
Abdul Ebrahim 《Physics letters. [Part B]》1978,72(4):457-461
The Cabibbo angle is related through spontaneous symmetry breaking to the masses of the light quarks in an illustrative model of quantum flavordynamics based on the SU2L × SU2R × U1 flavor gauge group and on four quark flavors. The agreement with experiment is quite good. 相似文献
999.
1000.
Low-temperature x-ray diffraction experiment has been carried out to investigate the 4 f-electron state of the low carrier density system CeSb which shows complicated magnetic phase diagrams at low temperatures. The scattering pattern of the satellite peaks observed in the magnetically ordered state AFP3 is explained well by the model which takes into account both the lattice and charge modulations corresponding to the complex magnetic structure. The present result gives direct evidence for the strong modulation of the 4 f-electron orbital state in CeSb due to the combined effect of the strong p-f mixing and carrier localization. 相似文献