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X-ray phase-sensitive microscope imaging with a grating interferometer:Theory and simulation
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作者 Jiecheng Yang Peiping Zhu +2 位作者 Dong Liang Hairong Zheng Yongshuai Ge 《Chinese Physics B》 SCIE EI CAS CSCD 2022年第9期652-657,共6页
A general theoretical framework is presented to explain the formation of the phase signal in an x-ray microscope integrated with a grating interferometer,which simultaneously enables the high spatial resolution imagin... A general theoretical framework is presented to explain the formation of the phase signal in an x-ray microscope integrated with a grating interferometer,which simultaneously enables the high spatial resolution imaging and the improved image contrast.By using this theory,several key parameters of phase contrast imaging can be predicted,for instance,the fringe visibility and period,and the conversion condition from the differential phase imaging(DPI)to the phase difference imaging(PDI).Additionally,numerical simulations are performed with certain x-ray optical components and imaging geometry.Comparison with the available experimental measurement[Appl.Phys.Lett.113063105(2018)]demonstrates the accuracy of this developed quantitative analysis method of x-ray phase-sensitive microscope imaging. 展开更多
关键词 x-ray phase contrast imaging x-ray microscope grating interferometer
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The Principle of Differentiation into Physical and Mathematical Theories
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作者 Anatoly Parfyonov 《Journal of High Energy Physics, Gravitation and Cosmology》 2023年第4期1208-1216,共9页
The article formulates the main principle of physics, which underlies this science. This principle has been called by the author of this article the Principle of differentiation into physical and mathematical theories... The article formulates the main principle of physics, which underlies this science. This principle has been called by the author of this article the Principle of differentiation into physical and mathematical theories. The article gives examples of the application of this principle in quantum mechanics and cosmology. A more detailed proof of the principle of equivalence of the electromagnetic field and the field of strong interaction to a free material particle is given. This principle, formulated in the article “Electrodynamics in Curvilinear Coordinates and the Equation of a Geodesic Line”, revealed the nature of the mass of elementary particles and became the basis for the formulation of the Principle of differentiation into physical and mathematical theories. 展开更多
关键词 Origin of the Universe Expansion of the Universe Corpuscular-Wave Dualism The Principle of Differentiation into Physical and Mathematical Theories
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Technological and Environmental Behavior of Coal Fly Ash in Lime-Based Materials 被引量:1
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作者 Mamoudou Sall Gora Dieye +4 位作者 Alassane Traoré Prince Momar Gueye Saliou Diouf Abdou Ciss Wade Djibril Diop 《Geomaterials》 2022年第2期15-29,共15页
Coal fly ash is considered an industrial by-product derived from coal combustion in thermal power plant. It is one of the most complex anthropogenic materials. Its improper disposal has become an environmental concern... Coal fly ash is considered an industrial by-product derived from coal combustion in thermal power plant. It is one of the most complex anthropogenic materials. Its improper disposal has become an environmental concern and resulted in a waste of recoverable resources. The aim of this paper is to study the physico-chemical characteristics of binders based on coal fly ash and lime in order to develop an eco-cement. The various characterization tests carried out are X-ray fluorescence, X-ray diffraction, compressive strengths, thermophysical properties and setting time. X-ray fluorescence and X-ray diffraction were used to determine the chemical composition and phases of fly ash, lime and binders. This allowed us to see that the chemical composition of fly ash is similar to that of cement. Compressive strengths of mortars containing 20%, 40%, 60% and 80% of fly ash have shown that fly ash has a long-term positive effect which might be related to a pozzolanic activity. The L<sub>3</sub> binder consisting of 60% of coal fly ash and 40% lime has a higher compressive strength than the others. The binder setting start time is greater than that of cement but shorter than that of lime. The study of the thermophysical properties of the L<sub>3</sub> binder shows that it has a higher thermal resistance than cement mortar. Moreover, it heats up less quickly because of its low effusivity compared to that of the latter. This analysis highlighted the principal characteristics that must be taken into account to use coal fly correctly in lime-based materials. 展开更多
关键词 Coal Fly Ash LIME BINDER X-Ray Fluorescence X-Ray Diffraction Thermomechanical Behavior
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Cosine fitting radiography and computed tomography
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作者 李盼云 张凯 +5 位作者 黄万霞 袁清习 王研 鞠在强 吴自玉 朱佩平 《Chinese Physics B》 SCIE EI CAS CSCD 2015年第6期679-686,共8页
A new method in diffraction-enhanced imaging computed tomography (DEI-CT) that follows the idea developed by Chapman et al. [Chapman D, Thomlinson W, Johnston R E, Washburn D, Pisano E, Gmur N, Zhong Z, Menk R, Arfe... A new method in diffraction-enhanced imaging computed tomography (DEI-CT) that follows the idea developed by Chapman et al. [Chapman D, Thomlinson W, Johnston R E, Washburn D, Pisano E, Gmur N, Zhong Z, Menk R, Arfelli F and Sayers D 1997 Phys. Med. BioL 42 2015] in 1997 is proposed in this paper. Merged with a "reverse projections" algorithm, only two sets of projection datasets at two defined orientations of the analyzer crystal are needed to reconstruct the linear absorption coefficient, the decrement of the real part of the refractive index and the linear scattering coefficient of the sample. Not only does this method reduce the delivered dose to the sample without degrading the image quality, but, compared with the existing DEI-CT approaches, it simplifies data-acquisition procedures. Experimental results confirm the reliability of this new method for DEI-CT applications. 展开更多
关键词 x-ray imaging diffraction-enhanced imaging phase contrast computed tomography
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Crystal and Molecular Structure of Ethyl 2-[(4-Hydroxy-phenyl)hydrazono]-3-oxobutanoate
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作者 Gnanasekaran Rajalakshmi Poomani Kumaradhas +3 位作者 Mahesh Padaki Arun M Isloor Chitrakara Hegede Balasubramanium Sridhar 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2011年第2期186-189,共4页
The title compound,C 12 N 2 O 4 H 14 (M r=250.3),crystallizes in triclinic P1 space group with a=7.7709(9),b=8.7534(11),c=9.6958(12),α=77.103(2),β=80.496(2),γ=86.726(2)o,V=633.9(1) 3,Z=2,F(000)=26... The title compound,C 12 N 2 O 4 H 14 (M r=250.3),crystallizes in triclinic P1 space group with a=7.7709(9),b=8.7534(11),c=9.6958(12),α=77.103(2),β=80.496(2),γ=86.726(2)o,V=633.9(1) 3,Z=2,F(000)=264,D c=1.311 Mg/m 3,μ(MoKα)=0.1 mm-1,the final R=0.056,and wR=0.15 for 2239 observed reflections (I 2σ(Ⅰ)).The molecules in the crystal are linked through O-H···O type of hydrogen bonding interaction forming an infinite chainlike structure.The phenylhydrazone ring and oxobutanoate groups are almost planar.The keto hydrazo group adopts a Z-configuration in the molecule and the torsion angle is-177.6(2)°. 展开更多
关键词 molecular structure oxobutanoate PHENYLHYDRAZONE Z-configuration hydrogen bonding
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Growth and Characterization of Dichloro Tris(Triphenyl Phosphine Oxide)Cadmium(II) —Second Harmonic Generation from a Centrosymmetric Crystal
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作者 K. Sreevani K. Thangaraj +3 位作者 K. Ramamurthi S. Selvanayagam B. Sridhar V. V. Anierudhe 《Journal of Minerals and Materials Characterization and Engineering》 2013年第1期20-23,共4页
The title compound dichloro tris(triphenyl phosphine oxide)cadmium(II) were grown by slow cooling method from aqueous solution. The title compound was synthesized and purified by repeated crystallization process. Grow... The title compound dichloro tris(triphenyl phosphine oxide)cadmium(II) were grown by slow cooling method from aqueous solution. The title compound was synthesized and purified by repeated crystallization process. Grown crystals were characterized by X-ray diffraction and FTIR analysis. The range of optical transmission was determined by recording UV-Vis-NIR spectrum. Thermal properties were investigated by DTA and TGA analyses. Its mechanical hardness was estimated by Vickers microhardness method. 展开更多
关键词 CRYSTAL GROWTH Single CRYSTAL X-Ray Diffraction ULTRAVIOLET Spectra Nonlinear Optical Crystals
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Comparative Characteristics of Hydrated Lime with Fine Sewage Sludge Ash (FSSA) and Coal Fly Ash (CFA)
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作者 Mamoudou Sall Abdou Ciss Wade +7 位作者 Gora Dieye Alassane Traoré Prince Momar Gueye Prince Momar Gueye Saliou Diouf Déthié Thiaw Khalifa Ababacar Diop Djibril Diop 《Journal of Minerals and Materials Characterization and Engineering》 CAS 2022年第5期446-459,共14页
The disposal of waste has become an environmental issue due to the limited available landfilling space. This paper aims to compare the characteristics of hydrated lime with fine sewage sludge ash (FSSA) and coal fly a... The disposal of waste has become an environmental issue due to the limited available landfilling space. This paper aims to compare the characteristics of hydrated lime with fine sewage sludge ash (FSSA) and coal fly ash (CFA). Multiple techniques, X-ray fluorescence (XRF), X-ray diffraction (XRD), the Fourier transform infrared (FTIR), compressive strengths, thermophysical properties, and setting time were used to assess the physicochemical characteristics of the lime-based materials. X-ray fluorescence and X-ray diffraction were used to determine the chemical composition and phases of ashes, lime and binders. The results showed that the chemical composition of ashes is similar to that of cement. Besides glass, the main minerals identified in CFA and FSSA are quartz (SiO<sub>2</sub>) and anhydrite (CaSO<sub>4</sub>). Moreover, calcium aluminium oxide (Ca<sub>3</sub>Al<sub>2</sub>O<sub>6</sub>) was detected for CFA and phosphorus calcium silicate (Ca<sub>2</sub>SiO<sub>4</sub>-Ca<sub>3</sub>(PO<sub>4</sub>)<sub>2</sub>) for FSSA and minor phases were detected for both. FTIR measurements were carried out to characterize the inorganics components of different samples. Compressive strengths of mortars with different formulations have shown that both have a long-term positive effect which might be related to a pozzolanic activity. For the CFA the L<sub>3</sub> binder consisting of 60% of coal fly ash and 40% lime has a higher compressive strength than the others while for the FSSA the L<sub>4</sub> binder consisting of 80% fine ash and 20% lime has a higher compressive strength than the others. Both binders setting start times are greater than that of cement but shorter than that of lime. The study of the thermophysical properties of binders shows that they have a higher thermal resistance than cement mortar. Moreover, binders heat up less quickly because of their low effusivity compared to cement. Lime-based materials system could be a promising option to both relieve the waste disposal pressure and provide a potential sustainable construction material. 展开更多
关键词 Coal Fly Ash Fine Sewage Sludge Ash LIME BINDER MICROSTRUCTURE Thermomechanical Behavior
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Light source system for high-precision flat-field correction and the calibration of an array detector 被引量:1
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作者 杨福桂 王秋实 李明 《Chinese Optics Letters》 SCIE EI CAS CSCD 2015年第4期6-10,共5页
Signal distortion due to the non-uniform response of the detector degrades the measurement accuracy of most metrology instruments. In this Letter, we report a newly developed calibration source system for reference-ba... Signal distortion due to the non-uniform response of the detector degrades the measurement accuracy of most metrology instruments. In this Letter, we report a newly developed calibration source system for reference-based non-uniformity correction using a laser source, a fiber, and a diffusive module. By applying the Monte Carlo simulation, we show that the transmittance of the system highly depends on the cavity reflection of the diffusive module. We also demonstrate the use of this system to achieve a flat field at a very low non-uniformity (less than 0.2%) with proper illumination intensity, which most costly commercial integrating sphere systems traditionally cannot provide. 展开更多
关键词 CALIBRATION Intelligent systems Light sources Monte Carlo methods
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Accurate reconstruction algorithm for bilateral differential phase signals
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作者 Qili He Yan Wang +9 位作者 Panyun Li Chunxia Yao Jin Zhang Tianyu Fu Kai Zhang Qingxi Yuan Wanxia Huang Shanfeng Wang Peiping Zhu Peng Liu 《Radiation Detection Technology and Methods》 CSCD 2021年第3期474-479,共6页
Background The differential phase computed tomography(DP-CT)imaging is a kind of X-ray-phase-based CT methods,which is widely used in various X-ray imaging laboratories.At present,a collection of projections with the ... Background The differential phase computed tomography(DP-CT)imaging is a kind of X-ray-phase-based CT methods,which is widely used in various X-ray imaging laboratories.At present,a collection of projections with the horizontal direc-tion(perpendicular to the sample rotation axis)DP information is often acquired in DP-CT.In an ideal experiment,if the background is zero,then we can accurately reconstruct the information of each direction of the sample with horizontal data only.Actually,background information will produce streaking artifacts to affect the resolution in directions other than the horizontal direction.Purpose To mitigate the streaking artifacts in the conventionally reconstructed DP-CT images.Method This study develops a novel analytical DP-CT reconstruction framework by jointly using the bilateral DP information obtained along two perpendicular directions.In addition,a new data acquisition scheme is also proposed to quickly acquire the bilateral DP signal without the need of changing the direction of refraction signal acquisition.Results Experimental results demonstrate that this new algorithm is able to greatly reduce the streaking artifacts on DP-CT images. 展开更多
关键词 X-ray phase Streaking artifacts BILATERAL
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