SY508-3-140[篇名]An Investigation into Application of Ceramic-Metal FGM Plating to Small High Speed Gasoline Engines，SY508-3-141[篇名] An X-ray method for determination of crystallinity as a function of depth from a ...SY508-3-140[篇名]An Investigation into Application of Ceramic-Metal FGM Plating to Small High Speed Gasoline Engines，SY508-3-141[篇名] An X-ray method for determination of crystallinity as a function of depth from a polymer surface，……展开更多
The coefficient and dynamics of water diffusion in adhesive-graphite joints were calculated in-situ with energy dispersive X-ray (EDX) analysis, a method that is significantly simpler than elemental analysis. Water di...The coefficient and dynamics of water diffusion in adhesive-graphite joints were calculated in-situ with energy dispersive X-ray (EDX) analysis, a method that is significantly simpler than elemental analysis. Water diffusion coefficient and dynamics of adhesive-graphite joints treated by different surface treatment methods were also investigated. Calculation results indicated that the water diffusion rate in adhesive-graphite joints treated by sandpaper was higher than that treated by chemical oxidation or by silane couple agent. Also the durability of graphite joints treated by coupling agent is superior to that treated by chemical oxidation or sandpaper burnishing.展开更多
The soft X-ray spectroscopy, laser Thomson scattering and electron cyclotron emission （ ECE ） are usually adopted for electron temperature measurement in fusion research of magnetic confinement. The particular soft ...The soft X-ray spectroscopy, laser Thomson scattering and electron cyclotron emission （ ECE ） are usually adopted for electron temperature measurement in fusion research of magnetic confinement. The particular soft X-ray spectroscopy has the very good spatial-temporal resolution and smaller measuring error than laser Thomson scattering, a close spatial-temporal resolution to ECE, absolute measurement ability, and smaller influence by suprathermal and runaway electrons than ECE.展开更多
A new statistical fitting approach, named Statistical Distribution-Based Analytic （SDA） method, is proposed to fit single Gaussian-shaped Ka and KI3 X-ray peaks recorded by Si（PIN） and silicon drift detector （SDD...A new statistical fitting approach, named Statistical Distribution-Based Analytic （SDA） method, is proposed to fit single Gaussian-shaped Ka and KI3 X-ray peaks recorded by Si（PIN） and silicon drift detector （SDD）. In this method, we use the dis- crete distribution theory to calculate standard deviation of energy resolution a. The calibration of cr and energy （E） for two de- tectors between the energy ranges of 4.5-26 keV are also completed by measuring characteristic X-ray spectra of nineteen types of pure elements. With the spectrum fraction （SF） parameter proposed in this paper, the SDA method can be used to re- solve overlapping peaks. In measured spectra, the Gaussian part of X-ray peaks can be fitted by a Gaussian function with two parameters, ~ and SF. This new fitting approach is simpler than traditional methods and it achieves relatively good results when fitting the complex X-ray spectra of national standard alloy samples detected by Si（PIN） and SDD detectors. The 3（2 values are obtained for each spectrum to assess fitting results, and the SDA fitting method gives a preferable fit for the SDD detector.展开更多
A new type of solid-conversion gas detector is investigated for high energy X-ray industrial computed tomography (HECT). The conversion efficiency is calculated by using the EGSnrc Monte Carlo code on the Linux platfo...A new type of solid-conversion gas detector is investigated for high energy X-ray industrial computed tomography (HECT). The conversion efficiency is calculated by using the EGSnrc Monte Carlo code on the Linux platform to simulate the transport process of photons and electrons in the detector. The simulation results show that the conversion efficiency could be more than 65%, if the X-ray beam width is less than about 0.2 mm, and a tungsten slab with 0.2 mm thickness and 30 mm length is employed as a radiation conversion medium. Meanwhile the results indicate that this new detector has higher conversion efficiency as well as less volume. Theoretically this new kind of detector could take place of the traditional scintillation detector for HECT.展开更多
Lead halide perovskites have attracted extensive attention in recent years because of their excellent photoelectronic properties, such as high absorption coefficients,carrier mobilities, defect tolerances, and photolu...Lead halide perovskites have attracted extensive attention in recent years because of their excellent photoelectronic properties, such as high absorption coefficients,carrier mobilities, defect tolerances, and photoluminescence efficiencies. However, a key issue hindering their commercial application is the toxicity of lead. Replacing lead with other nontoxic elements is a promising solution to this problem.Considering their atomic radii, relative atomic masses, and electron arrangements, perovskites based on Sn, Bi, Sb, and other elements instead of Pb have been widely synthesized.Here, we summarized the growth methods, photoelectric properties, and device applications of these lead-free perovskites. First, we introduced several common growth methods for lead-free perovskites, including solution methods,solid-state reaction, and chemical vapor deposition methods.Second, we discussed the photoelectric properties and methods for optimizing these properties of lead-free perovskites with different structure dimensions. Finally, the applications of lead-free perovskites in solar cells, light-emitting diodes,and X-ray detectors were examined. This review also provides suggestions for future research on lead-free perovskites.展开更多
A Mythen detector has been equipped at the beamline 4B9A of Beijing Synchrotron Radiation Facility （BSRF）, which is expected to enable BSRF to perform time-resolved measurement of X-ray diffraction （XRD） full-prof...A Mythen detector has been equipped at the beamline 4B9A of Beijing Synchrotron Radiation Facility （BSRF）, which is expected to enable BSRF to perform time-resolved measurement of X-ray diffraction （XRD） full-profiles. In this paper, the thermal expansion behavior of metal indium has been studied by using the in-situ XRD technique with the Mythen detector. The indium was heated from 303 to 433 K with a heating rate of 2 K/rain. The in-situ XRD full-profiles were collected with a rate of one profile per 10 seconds. Rietveld refinement was used to extract the structural parameters. The results demonstrate that these collected quasi-real-time XRD profiles can be well used for structural analysis. The metal indium was found to have a nonlinear thermal expansion behavior from room temperature to the melting point （429.65 K）. The a-axis of the tetragonal unit cell expands with a biquadratic dependency on temperature, while the c-axis contracts with a cubic dependency on temperature. By the time-resolved XRD measurements, it was observed that the [200] preferred orientation can maintain to about 403.15 K. While （110） is the last and detectable crystal plane just before melting of the polycrystalline indium foil. This study is not only beneficial to the application of metal indium, but also exhibits the capacity of in-situ time-resolved XRD measurements at the X-ray diffraction station of BSRF.展开更多
文摘SY508-3-140[篇名]An Investigation into Application of Ceramic-Metal FGM Plating to Small High Speed Gasoline Engines，SY508-3-141[篇名] An X-ray method for determination of crystallinity as a function of depth from a polymer surface，……
文摘The coefficient and dynamics of water diffusion in adhesive-graphite joints were calculated in-situ with energy dispersive X-ray (EDX) analysis, a method that is significantly simpler than elemental analysis. Water diffusion coefficient and dynamics of adhesive-graphite joints treated by different surface treatment methods were also investigated. Calculation results indicated that the water diffusion rate in adhesive-graphite joints treated by sandpaper was higher than that treated by chemical oxidation or by silane couple agent. Also the durability of graphite joints treated by coupling agent is superior to that treated by chemical oxidation or sandpaper burnishing.
文摘The soft X-ray spectroscopy, laser Thomson scattering and electron cyclotron emission （ ECE ） are usually adopted for electron temperature measurement in fusion research of magnetic confinement. The particular soft X-ray spectroscopy has the very good spatial-temporal resolution and smaller measuring error than laser Thomson scattering, a close spatial-temporal resolution to ECE, absolute measurement ability, and smaller influence by suprathermal and runaway electrons than ECE.
基金supported by the National Natural Science Foundation of China(Grant Nos.40974065,41025015)the National High Technology Research and Development Program of China(Grant No.2012AA063501)Ph.D.Programs Foundation of Ministry of Education of China(Grant No.20125122110009)
文摘A new statistical fitting approach, named Statistical Distribution-Based Analytic （SDA） method, is proposed to fit single Gaussian-shaped Ka and KI3 X-ray peaks recorded by Si（PIN） and silicon drift detector （SDD）. In this method, we use the dis- crete distribution theory to calculate standard deviation of energy resolution a. The calibration of cr and energy （E） for two de- tectors between the energy ranges of 4.5-26 keV are also completed by measuring characteristic X-ray spectra of nineteen types of pure elements. With the spectrum fraction （SF） parameter proposed in this paper, the SDA method can be used to re- solve overlapping peaks. In measured spectra, the Gaussian part of X-ray peaks can be fitted by a Gaussian function with two parameters, ~ and SF. This new fitting approach is simpler than traditional methods and it achieves relatively good results when fitting the complex X-ray spectra of national standard alloy samples detected by Si（PIN） and SDD detectors. The 3（2 values are obtained for each spectrum to assess fitting results, and the SDA fitting method gives a preferable fit for the SDD detector.
基金supported by the National Natural Science Foundation of China (No.60672098)the Tackling Key Problems of Science and Technology of ChongQing (No.CSTC2009AC3047)
文摘A new type of solid-conversion gas detector is investigated for high energy X-ray industrial computed tomography (HECT). The conversion efficiency is calculated by using the EGSnrc Monte Carlo code on the Linux platform to simulate the transport process of photons and electrons in the detector. The simulation results show that the conversion efficiency could be more than 65%, if the X-ray beam width is less than about 0.2 mm, and a tungsten slab with 0.2 mm thickness and 30 mm length is employed as a radiation conversion medium. Meanwhile the results indicate that this new detector has higher conversion efficiency as well as less volume. Theoretically this new kind of detector could take place of the traditional scintillation detector for HECT.
基金Ministry of Science and Technology (2017YFA0205004, 2016YFA0200700)the Strategic Priority Research Program of the Chinese Academy of Sciences (XDB36000000)+2 种基金the National Natural Science Foundation of China (61704038, 21673054, 11874130, 12074086, 61307120, 61704038 and 11474187)the Open Research Fund Program of the State Key Laboratory of Low-Dimensional Quantum Physics (KF201902)the CAS Instrument Development Project (Y950291) for their support。
文摘Lead halide perovskites have attracted extensive attention in recent years because of their excellent photoelectronic properties, such as high absorption coefficients,carrier mobilities, defect tolerances, and photoluminescence efficiencies. However, a key issue hindering their commercial application is the toxicity of lead. Replacing lead with other nontoxic elements is a promising solution to this problem.Considering their atomic radii, relative atomic masses, and electron arrangements, perovskites based on Sn, Bi, Sb, and other elements instead of Pb have been widely synthesized.Here, we summarized the growth methods, photoelectric properties, and device applications of these lead-free perovskites. First, we introduced several common growth methods for lead-free perovskites, including solution methods,solid-state reaction, and chemical vapor deposition methods.Second, we discussed the photoelectric properties and methods for optimizing these properties of lead-free perovskites with different structure dimensions. Finally, the applications of lead-free perovskites in solar cells, light-emitting diodes,and X-ray detectors were examined. This review also provides suggestions for future research on lead-free perovskites.
基金supported by the National Natural Science Foundationof China(Grant Nos.U1232203,U1432104,11405199,11305198 and U1332107)the special fund on repairing infrastructure and purchasing fixed assets of Ministry of Finance of China
文摘A Mythen detector has been equipped at the beamline 4B9A of Beijing Synchrotron Radiation Facility （BSRF）, which is expected to enable BSRF to perform time-resolved measurement of X-ray diffraction （XRD） full-profiles. In this paper, the thermal expansion behavior of metal indium has been studied by using the in-situ XRD technique with the Mythen detector. The indium was heated from 303 to 433 K with a heating rate of 2 K/rain. The in-situ XRD full-profiles were collected with a rate of one profile per 10 seconds. Rietveld refinement was used to extract the structural parameters. The results demonstrate that these collected quasi-real-time XRD profiles can be well used for structural analysis. The metal indium was found to have a nonlinear thermal expansion behavior from room temperature to the melting point （429.65 K）. The a-axis of the tetragonal unit cell expands with a biquadratic dependency on temperature, while the c-axis contracts with a cubic dependency on temperature. By the time-resolved XRD measurements, it was observed that the [200] preferred orientation can maintain to about 403.15 K. While （110） is the last and detectable crystal plane just before melting of the polycrystalline indium foil. This study is not only beneficial to the application of metal indium, but also exhibits the capacity of in-situ time-resolved XRD measurements at the X-ray diffraction station of BSRF.
