Rapidly solidified Al87Ni7Cu3Nd3 amorphous alloy was prepared by using melt spinning. Its calorimetric behavior was characterized by using differential scanning calorimeter in a continuous or isothermal heating mode. ...Rapidly solidified Al87Ni7Cu3Nd3 amorphous alloy was prepared by using melt spinning. Its calorimetric behavior was characterized by using differential scanning calorimeter in a continuous or isothermal heating mode. phase transformation was investigated, with a special interest in primary crystallization, by using an in-situ examination of X-ray diffractometry （XRD） and high resolution transmission electron microscopy （HRTEM）. The results show that, the whole devitrification of rapidly solidified Al87NiyCu3Nd3 amorphous alloy involves two main processes of primary crystallization and secondary crystallization that consist mainly of two reactions. For primary crystallization, the apparent activation energies, EIso and EKis and growth activation energies Eg are about 153, 166 and 288 kJ/mol, respectively. The interdiffusion of Al atoms is a rate-controlled step of formation of the a（Al） particles, but slow diffusion of Ni and Nd atoms plays a significant role in retarding growth of the α （Al） particles. For secondary crystallization, EIso, EKis and Eg of the first reaction are about 291,208 and 290 kJ/mol, and those of the second reaction are about 367, 269 and 372 kJ/mol. The two reactions of secondary crystallization are controlled mainly in an interface-controlled three-dimensional mode, depending mainly on slow diffusion of Ni and Nd atoms.展开更多
Based on the study of Walsh transformation,the zooming template of a two dimensional superimposure filter is decomposed and simplified,and it is real time implemented with FPGA.This method is simple and effective.Th...Based on the study of Walsh transformation,the zooming template of a two dimensional superimposure filter is decomposed and simplified,and it is real time implemented with FPGA.This method is simple and effective.The quality of the image is very good.展开更多
In this paper,we calculate the resolution of a photorefractive incoherent-to-coherent optical converter on the image plane for small diffraction efficiency by taking into account the optical imaging characteristics of...In this paper,we calculate the resolution of a photorefractive incoherent-to-coherent optical converter on the image plane for small diffraction efficiency by taking into account the optical imaging characteristics of the imaging lens.For a thin grating,we obtain a high resolution,which is comparable with the experimental results.展开更多
Primary non-Hodgkin’s lymphoma of the esophagus is a rare disease.A case of primary isolated nonHodgkin’s lymphoma of the esophagus in a 77-yearold man without acquired immunodeficiency syndrome is presented.We desc...Primary non-Hodgkin’s lymphoma of the esophagus is a rare disease.A case of primary isolated nonHodgkin’s lymphoma of the esophagus in a 77-yearold man without acquired immunodeficiency syndrome is presented.We describe the clinical features and the imaging findings(barium swallow,endoscopic ultrasonography and CT)of a biopsy proven B-cell lymphoma with diffuse transmural involvement of the esophagus wall,which was discovered incidentally.We also briefly review the literature.展开更多
Due to the limited scenes that synthetic aperture radar(SAR)satellites can detect,the full-track utilization rate is not high.Because of the computing and storage limitation of one satellite,it is difficult to process...Due to the limited scenes that synthetic aperture radar(SAR)satellites can detect,the full-track utilization rate is not high.Because of the computing and storage limitation of one satellite,it is difficult to process large amounts of data of spaceborne synthetic aperture radars.It is proposed to use a new method of networked satellite data processing for improving the efficiency of data processing.A multi-satellite distributed SAR real-time processing method based on Chirp Scaling(CS)imaging algorithm is studied in this paper,and a distributed data processing system is built with field programmable gate array(FPGA)chips as the kernel.Different from the traditional CS algorithm processing,the system divides data processing into three stages.The computing tasks are reasonably allocated to different data processing units(i.e.,satellites)in each stage.The method effectively saves computing and storage resources of satellites,improves the utilization rate of a single satellite,and shortens the data processing time.Gaofen-3(GF-3)satellite SAR raw data is processed by the system,with the performance of the method verified.展开更多
A single Complementary Metal Oxide Semiconductor (CMOS) image sensor based on 0.35μm process along with its design and implementation is introduced in this paper. The pixel ar-chitecture of Active Pixel Sensor (APS) ...A single Complementary Metal Oxide Semiconductor (CMOS) image sensor based on 0.35μm process along with its design and implementation is introduced in this paper. The pixel ar-chitecture of Active Pixel Sensor (APS) is used in the chip,which comprises a 256×256 pixel array together with column amplifiers,scan array circuits,series interface,control logic and Analog-Digital Converter (ADC). With the use of smart layout design,fill factor of pixel cell is 43%. Moreover,a new method of Dynamic Digital Double Sample (DDDS) which removes Fixed Pattern Noise (FPN) is used. The CMOS image sensor chip is implemented based on the 0.35μm process of chartered by Multi-Project Wafer (MPW). This chip performs well as expected.展开更多
We describe a 15-mm scirrhous hepatocellular carcinoma （HCC） in a 60-year-old man with B-type cirrhosis. Ultrasound disclosed a 15-mm hypoechoic nodule in segment 7. Contrast-enhanced US revealed heterogeneous, not ...We describe a 15-mm scirrhous hepatocellular carcinoma （HCC） in a 60-year-old man with B-type cirrhosis. Ultrasound disclosed a 15-mm hypoechoic nodule in segment 7. Contrast-enhanced US revealed heterogeneous, not diffuse, hypervascularity in the early phase and a defect in the Kupffer phase.Contrast-enhanced computed tomography （CT） revealed a heterogeneous hypervascular nodule in the early phase and a low-density area in the late phase.Magnetic resonance imaging （MRI） revealed iso- to hypointensity at T1 and high intensity at T2-weighted sequences. Contrast-enhanced MRI also revealed a heterogeneous hypervascular nodule in the early phase and washout in the late phase. Super-paramagnetic iron oxide-MRI revealed a hvoerintense nodule. CT during hepatic arteriography and CT during arterial portography revealed heterogeneous hyperattenuation and a perfusion defect, respectively. Based on these imaging findings the nodule was diagnosed as a mixed well-differentiated and moderately-differentiated HCC.Histologically, the nodule was moderately-differentiated HCC characterized by typical cytological and structural atypia with dense fibrosis. Immunohistochemically,the nodule was positive for heterochromatin protein 1 and alpha-smooth muscle actin, and negative for cytokeratin 19. From the above findings, the nodule was diagnosed as scirrhous HCC. Clinicians engaged in hepatology should exercise caution with suspected scirrhous HCC when imaging studies reveal atypical findings, as shown in our case on the basis of chronic liver disease.展开更多
基金Project(2005-5) supported by the Postdoctoral Foundation of Central South University, ChinaProject(2005038560) supported by the Postdoctoral Science Foundation of China
文摘Rapidly solidified Al87Ni7Cu3Nd3 amorphous alloy was prepared by using melt spinning. Its calorimetric behavior was characterized by using differential scanning calorimeter in a continuous or isothermal heating mode. phase transformation was investigated, with a special interest in primary crystallization, by using an in-situ examination of X-ray diffractometry （XRD） and high resolution transmission electron microscopy （HRTEM）. The results show that, the whole devitrification of rapidly solidified Al87NiyCu3Nd3 amorphous alloy involves two main processes of primary crystallization and secondary crystallization that consist mainly of two reactions. For primary crystallization, the apparent activation energies, EIso and EKis and growth activation energies Eg are about 153, 166 and 288 kJ/mol, respectively. The interdiffusion of Al atoms is a rate-controlled step of formation of the a（Al） particles, but slow diffusion of Ni and Nd atoms plays a significant role in retarding growth of the α （Al） particles. For secondary crystallization, EIso, EKis and Eg of the first reaction are about 291,208 and 290 kJ/mol, and those of the second reaction are about 367, 269 and 372 kJ/mol. The two reactions of secondary crystallization are controlled mainly in an interface-controlled three-dimensional mode, depending mainly on slow diffusion of Ni and Nd atoms.
基金Supported by National Nine-Five Project(No. 0 3 0 3 )
文摘Based on the study of Walsh transformation,the zooming template of a two dimensional superimposure filter is decomposed and simplified,and it is real time implemented with FPGA.This method is simple and effective.The quality of the image is very good.
文摘In this paper,we calculate the resolution of a photorefractive incoherent-to-coherent optical converter on the image plane for small diffraction efficiency by taking into account the optical imaging characteristics of the imaging lens.For a thin grating,we obtain a high resolution,which is comparable with the experimental results.
文摘Primary non-Hodgkin’s lymphoma of the esophagus is a rare disease.A case of primary isolated nonHodgkin’s lymphoma of the esophagus in a 77-yearold man without acquired immunodeficiency syndrome is presented.We describe the clinical features and the imaging findings(barium swallow,endoscopic ultrasonography and CT)of a biopsy proven B-cell lymphoma with diffuse transmural involvement of the esophagus wall,which was discovered incidentally.We also briefly review the literature.
基金Project(2017YFC1405600)supported by the National Key R&D Program of ChinaProject(18JK05032)supported by the Scientific Research Project of Education Department of Shaanxi Province,China。
文摘Due to the limited scenes that synthetic aperture radar(SAR)satellites can detect,the full-track utilization rate is not high.Because of the computing and storage limitation of one satellite,it is difficult to process large amounts of data of spaceborne synthetic aperture radars.It is proposed to use a new method of networked satellite data processing for improving the efficiency of data processing.A multi-satellite distributed SAR real-time processing method based on Chirp Scaling(CS)imaging algorithm is studied in this paper,and a distributed data processing system is built with field programmable gate array(FPGA)chips as the kernel.Different from the traditional CS algorithm processing,the system divides data processing into three stages.The computing tasks are reasonably allocated to different data processing units(i.e.,satellites)in each stage.The method effectively saves computing and storage resources of satellites,improves the utilization rate of a single satellite,and shortens the data processing time.Gaofen-3(GF-3)satellite SAR raw data is processed by the system,with the performance of the method verified.
文摘A single Complementary Metal Oxide Semiconductor (CMOS) image sensor based on 0.35μm process along with its design and implementation is introduced in this paper. The pixel ar-chitecture of Active Pixel Sensor (APS) is used in the chip,which comprises a 256×256 pixel array together with column amplifiers,scan array circuits,series interface,control logic and Analog-Digital Converter (ADC). With the use of smart layout design,fill factor of pixel cell is 43%. Moreover,a new method of Dynamic Digital Double Sample (DDDS) which removes Fixed Pattern Noise (FPN) is used. The CMOS image sensor chip is implemented based on the 0.35μm process of chartered by Multi-Project Wafer (MPW). This chip performs well as expected.
文摘We describe a 15-mm scirrhous hepatocellular carcinoma （HCC） in a 60-year-old man with B-type cirrhosis. Ultrasound disclosed a 15-mm hypoechoic nodule in segment 7. Contrast-enhanced US revealed heterogeneous, not diffuse, hypervascularity in the early phase and a defect in the Kupffer phase.Contrast-enhanced computed tomography （CT） revealed a heterogeneous hypervascular nodule in the early phase and a low-density area in the late phase.Magnetic resonance imaging （MRI） revealed iso- to hypointensity at T1 and high intensity at T2-weighted sequences. Contrast-enhanced MRI also revealed a heterogeneous hypervascular nodule in the early phase and washout in the late phase. Super-paramagnetic iron oxide-MRI revealed a hvoerintense nodule. CT during hepatic arteriography and CT during arterial portography revealed heterogeneous hyperattenuation and a perfusion defect, respectively. Based on these imaging findings the nodule was diagnosed as a mixed well-differentiated and moderately-differentiated HCC.Histologically, the nodule was moderately-differentiated HCC characterized by typical cytological and structural atypia with dense fibrosis. Immunohistochemically,the nodule was positive for heterochromatin protein 1 and alpha-smooth muscle actin, and negative for cytokeratin 19. From the above findings, the nodule was diagnosed as scirrhous HCC. Clinicians engaged in hepatology should exercise caution with suspected scirrhous HCC when imaging studies reveal atypical findings, as shown in our case on the basis of chronic liver disease.
