On May 6, 2009, the X-ray imaging and biomedical application beamline(BL13W1) at Shanghai Synchrotron Radiation Facility(SSRF) officially opened to users, with 8–72.5 ke V X-rays. The experimental station is equipped...On May 6, 2009, the X-ray imaging and biomedical application beamline(BL13W1) at Shanghai Synchrotron Radiation Facility(SSRF) officially opened to users, with 8–72.5 ke V X-rays. The experimental station is equipped with four sets of X-ray CCD detectors of different pixel size(0.19–24 μm) for on-line phase-contrast imaging and micro-CT imaging with 0.8 μm spatial resolution and 1 ms temporal resolution. An in vivo microCT experiment for a living insect was realized in 4 s. An X-ray fluorescence detector is equipped for X-ray fluorescence mapping imaging and X-ray fluorescence micro-CT imaging with 50 μm spatial resolution. In order to meet different requirements from the users, several experimental methods, such as X-ray spiral micro-CT, Xray local micro-CT, X-ray fast micro-CT, X-ray grating-based differential micro-CT, X-ray fluorescence microCT and X-ray quantitative micro-CT have been developed, and nearly 60 papers related to those developments for this beamline have been published. Moreover, the beamline has realized the remote fast CT reconstruction,providing a great convenience for the users to process experimental data at their offices. As of August 2014,the beamline has offered the user beamtime of(23 145 h), from which 232 user papers have been published,including 151 SCI papers and 55 papers with SCI impact factor > 3. The quantity and quality of the user paper outcome keep a steady increase. Some typical user experimental results are introduced.展开更多
In most collisional schemes of x-ray laser （XRL） experiments, a bow-like intensity distribution of XRL is often observed, and it is generally ascribed to the two-dimensional hydrodynamic behaviour of expanding plasm...In most collisional schemes of x-ray laser （XRL） experiments, a bow-like intensity distribution of XRL is often observed, and it is generally ascribed to the two-dimensional hydrodynamic behaviour of expanding plasma. In order to better understand its essence in physics, a newly developed two-dimensional non-equilibrium radiation hydrodynamic code XRL2D is used to simulate a quasi-steady state Ni-like Ag XRL experiment on ShenGuang-Ⅱfacility. The simulation results show that the bow-like distribution of Ni-like ions caused by over-ionization in the central area of plasma is responsible for the bow-like shape of the XRL intensity distribution observed.展开更多
The present research was conducted in Line X tester analysis for estimating combining ability and heterotic effects,restorers malesterile(CMS) crossed with seven tester lines 3x7 21 F_1 hybrids of sunflower were furth...The present research was conducted in Line X tester analysis for estimating combining ability and heterotic effects,restorers malesterile(CMS) crossed with seven tester lines 3x7 21 F_1 hybrids of sunflower were further used to estimate their general combining ability(GCS),specific combining ability(SCA) and heterosis effects on main traits of sunflower during 2009.For this study,seven lines of sunflower were tested with three testers 7x3 of sunflower to obtain twenty one F_1 genotypes from Line X tester mating design.It was concluded from present study that among the lines,0505 Cms-6,Peshawer-93 Cms-11,Peshawar-93 Cms-12 were the best general combiners to play the vital role in flowering,maturity,plant height,head diameter,seed index,grain per head and 100-grain yield per plant.While RHP-53,RHP-42,RHP-46 were also the best combiners for all the traits.However,hybrid 54CMS-1 x RHP-42 showed best specific combiners,while Peshawer-93 exhibited good specific combiners for grain yield per plant,the hybrids,plant height,head diameter,seed index,grain per head and grain yield per plant,respectively.Significant differences among the tested sunflower genotypes with regard to mean values of all the investigated traits were determined.The analysis of variance of combining abilities and the analysis of genetic variance components confirmed the non-additive component.展开更多
In-line x-ray phase contrast imaging has attracted much attention due to two major advantages： its effectiveness in imaging weakly absorbing materials, and the simplicity of its facilities. In this paper a comprehens...In-line x-ray phase contrast imaging has attracted much attention due to two major advantages： its effectiveness in imaging weakly absorbing materials, and the simplicity of its facilities. In this paper a comprehensive theory based on Wigner distribution developed by Wu and Liu [Med. Phys. 31 2378-2384 （2004）] is reviewed. The influence of x-ray source and detector on the image is discussed. Experiments using a microfocus x-ray source and a CCD detector are conducted, which show the role of two key factors on imaging： the tube voltage and tube current. High tube current and moderate tube voltage are suggested for imaging.展开更多
The purpose of the current study is to evaluate the ageing of poly(ethylene-co-propylene) fittings produced by several manufacturers. The fittings were aged for varying times as follows: 0, 2, 13, 23, 45, 106, 225 and...The purpose of the current study is to evaluate the ageing of poly(ethylene-co-propylene) fittings produced by several manufacturers. The fittings were aged for varying times as follows: 0, 2, 13, 23, 45, 106, 225 and 391 days at 100°C. In a previous paper, the oxidation induction time (OItime) and oxidation induction temperature (OItemp) were evaluated with respect to every single step of the ageing process [1]. Here, the Vickers microhardness and wide-angle X-ray line width were used for characterization of the oxidative stability of poly(ethylene-co-propylene) pipes. Both the Vickers microhardness and wide-angle X-ray line width as evaluated from a certain reflex of the diffractogram generally increase with ageing for most samples. The higher microhardness is most likely related to higher fragility of the pipes. The increase of the X-ray line width with ageing indirectly proves that reducing the crystallite size as well as increase of the crystallite defectiveness take place.展开更多
Based on the two-dimensional model, this paper compares the hydrodynamics of slab x-ray laser plasma produced by different nonuniform line focused irradiations. It finds that the average intensity and the duration of ...Based on the two-dimensional model, this paper compares the hydrodynamics of slab x-ray laser plasma produced by different nonuniform line focused irradiations. It finds that the average intensity and the duration of laser pulse and the overall shape of the intensity distribution in the focal line have different influences on the plasma. Calculations show that the evolution of temperature variation is more sensitive to the pulse duration and the electron density variation is more sensitive to the pulse intensity. Pulses with duration of 200 ps to 500 ps and with intensity of 0.2 TW/cm2 to 1.0 TW/cm2 are proved acceptable in slab x-ray lasers.展开更多
We report on our research on the UV, optical line parameters and the infrared through UV to soft X-ray continuum parameters for a composite sample of narrow line and normal Seyfert 1 galaxies. The strong correlations ...We report on our research on the UV, optical line parameters and the infrared through UV to soft X-ray continuum parameters for a composite sample of narrow line and normal Seyfert 1 galaxies. The strong correlations among the line width of HB, optical line strength of Fell and the soft X-ray slope are confirmed. We found no correlations between the UV line parameters, the equivalent widths of Lya and CIV and their ratio on one hand and the optical line parameters on the other. The UV and X-ray luminosities strongly correlate with the line widths of HB and the Fe II/HB ratio. No significant correlation is found between the infrared-soft X-my continuum slope aix and the line width of HB.展开更多
基金Supported by the National Natural Science Foundation of China(Nos.11475248 and 11105213)
文摘On May 6, 2009, the X-ray imaging and biomedical application beamline(BL13W1) at Shanghai Synchrotron Radiation Facility(SSRF) officially opened to users, with 8–72.5 ke V X-rays. The experimental station is equipped with four sets of X-ray CCD detectors of different pixel size(0.19–24 μm) for on-line phase-contrast imaging and micro-CT imaging with 0.8 μm spatial resolution and 1 ms temporal resolution. An in vivo microCT experiment for a living insect was realized in 4 s. An X-ray fluorescence detector is equipped for X-ray fluorescence mapping imaging and X-ray fluorescence micro-CT imaging with 50 μm spatial resolution. In order to meet different requirements from the users, several experimental methods, such as X-ray spiral micro-CT, Xray local micro-CT, X-ray fast micro-CT, X-ray grating-based differential micro-CT, X-ray fluorescence microCT and X-ray quantitative micro-CT have been developed, and nearly 60 papers related to those developments for this beamline have been published. Moreover, the beamline has realized the remote fast CT reconstruction,providing a great convenience for the users to process experimental data at their offices. As of August 2014,the beamline has offered the user beamtime of(23 145 h), from which 232 user papers have been published,including 151 SCI papers and 55 papers with SCI impact factor > 3. The quantity and quality of the user paper outcome keep a steady increase. Some typical user experimental results are introduced.
文摘In most collisional schemes of x-ray laser （XRL） experiments, a bow-like intensity distribution of XRL is often observed, and it is generally ascribed to the two-dimensional hydrodynamic behaviour of expanding plasma. In order to better understand its essence in physics, a newly developed two-dimensional non-equilibrium radiation hydrodynamic code XRL2D is used to simulate a quasi-steady state Ni-like Ag XRL experiment on ShenGuang-Ⅱfacility. The simulation results show that the bow-like distribution of Ni-like ions caused by over-ionization in the central area of plasma is responsible for the bow-like shape of the XRL intensity distribution observed.
文摘The present research was conducted in Line X tester analysis for estimating combining ability and heterotic effects,restorers malesterile(CMS) crossed with seven tester lines 3x7 21 F_1 hybrids of sunflower were further used to estimate their general combining ability(GCS),specific combining ability(SCA) and heterosis effects on main traits of sunflower during 2009.For this study,seven lines of sunflower were tested with three testers 7x3 of sunflower to obtain twenty one F_1 genotypes from Line X tester mating design.It was concluded from present study that among the lines,0505 Cms-6,Peshawer-93 Cms-11,Peshawar-93 Cms-12 were the best general combiners to play the vital role in flowering,maturity,plant height,head diameter,seed index,grain per head and 100-grain yield per plant.While RHP-53,RHP-42,RHP-46 were also the best combiners for all the traits.However,hybrid 54CMS-1 x RHP-42 showed best specific combiners,while Peshawer-93 exhibited good specific combiners for grain yield per plant,the hybrids,plant height,head diameter,seed index,grain per head and grain yield per plant,respectively.Significant differences among the tested sunflower genotypes with regard to mean values of all the investigated traits were determined.The analysis of variance of combining abilities and the analysis of genetic variance components confirmed the non-additive component.
基金Project supported by the National Natural Science Foundation of China （Grant No 10475044）.
文摘In-line x-ray phase contrast imaging has attracted much attention due to two major advantages： its effectiveness in imaging weakly absorbing materials, and the simplicity of its facilities. In this paper a comprehensive theory based on Wigner distribution developed by Wu and Liu [Med. Phys. 31 2378-2384 （2004）] is reviewed. The influence of x-ray source and detector on the image is discussed. Experiments using a microfocus x-ray source and a CCD detector are conducted, which show the role of two key factors on imaging： the tube voltage and tube current. High tube current and moderate tube voltage are suggested for imaging.
文摘The purpose of the current study is to evaluate the ageing of poly(ethylene-co-propylene) fittings produced by several manufacturers. The fittings were aged for varying times as follows: 0, 2, 13, 23, 45, 106, 225 and 391 days at 100°C. In a previous paper, the oxidation induction time (OItime) and oxidation induction temperature (OItemp) were evaluated with respect to every single step of the ageing process [1]. Here, the Vickers microhardness and wide-angle X-ray line width were used for characterization of the oxidative stability of poly(ethylene-co-propylene) pipes. Both the Vickers microhardness and wide-angle X-ray line width as evaluated from a certain reflex of the diffractogram generally increase with ageing for most samples. The higher microhardness is most likely related to higher fragility of the pipes. The increase of the X-ray line width with ageing indirectly proves that reducing the crystallite size as well as increase of the crystallite defectiveness take place.
基金suported by the National Natural Science Foundation of China (Grant No. 10874242)the National Basic Research Program of China (973 Program) (Grant No. 2007CB815105)Research Fund for the Doctoral Program of Higher Education of China (Grant No. 20070290008)
文摘Based on the two-dimensional model, this paper compares the hydrodynamics of slab x-ray laser plasma produced by different nonuniform line focused irradiations. It finds that the average intensity and the duration of laser pulse and the overall shape of the intensity distribution in the focal line have different influences on the plasma. Calculations show that the evolution of temperature variation is more sensitive to the pulse duration and the electron density variation is more sensitive to the pulse intensity. Pulses with duration of 200 ps to 500 ps and with intensity of 0.2 TW/cm2 to 1.0 TW/cm2 are proved acceptable in slab x-ray lasers.
基金the National Natural Science Foundationof China and Chinese Panden Project.
文摘We report on our research on the UV, optical line parameters and the infrared through UV to soft X-ray continuum parameters for a composite sample of narrow line and normal Seyfert 1 galaxies. The strong correlations among the line width of HB, optical line strength of Fell and the soft X-ray slope are confirmed. We found no correlations between the UV line parameters, the equivalent widths of Lya and CIV and their ratio on one hand and the optical line parameters on the other. The UV and X-ray luminosities strongly correlate with the line widths of HB and the Fe II/HB ratio. No significant correlation is found between the infrared-soft X-my continuum slope aix and the line width of HB.
