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X-ray Manifestations of Pneumoconiosis Patients and Differential Analysis with Pulmonary Tuberculosis
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作者 Gaocai XIONG Yuanfeng YANG +2 位作者 Wei ZHANG Mingbi LYU Tingqian LIU 《Agricultural Biotechnology》 CAS 2023年第3期75-78,共4页
[Objectives]This study was conducted to explore the X-ray manifestations of pneumoconiosis patients and differentiation from pulmonary tuberculosis.[Methods]Retrospective analysis was conducted on 103 patients who und... [Objectives]This study was conducted to explore the X-ray manifestations of pneumoconiosis patients and differentiation from pulmonary tuberculosis.[Methods]Retrospective analysis was conducted on 103 patients who underwent lung examinations,including 47 cases of pneumoconiosis and 56 cases of pulmonary tuberculosis.The differences in nodule characteristics and accompanying cavity sign between pneumoconiosis and pulmonary tuberculosis were compared.[Results]The X-ray manifestations of pneumoconiosis patients mainly included various forms of lung images,which were uneven in density,and had blurry edges,and sometimes thickening of lung markings and reduction of lung volume could be observed.The acinar nodules observed in X-ray films of patients with hematogenous disseminated pulmonary tuberculosis appeared petal like.The uniformity of nodule appearance such as nodule distribution,nodule density,and nodule size was significantly lower in pneumoconiosis than in hematogenous disseminated pulmonary tuberculosis,showing a statistical significance(P<0.05).The diameter of cavities in patients with pneumoconiosis accompanied by cavity sign[(0.64±0.13 vs 3.37±0.95)cm]was lower than that in patients with secondary pulmonary tuberculosis accompanied by cavity sign.There was a significant difference in the thickness of the cavity wall between the two diseases,and patients with pneumoconiosis accompanied by cavity sign had a higher rate of thick wall cavities(>3 mm).The X-ray manifestations of pneumoconiosis and tuberculosis were relatively similar,but the distribution,density and size of nodules in pneumoconiosis were relatively uneven,and the patients accompanied by cavity sign had smaller cavity diameter and higher rate of thick-walled cavities.[Conclusions]This study provides a reference for the clinical differential diagnosis of pneumoconiosis and pulmonary tuberculosis. 展开更多
关键词 PNEUMOCONIOSIS Pulmonary tuberculosis x-ray Cavity sign differential analysis
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Role of Plain Abdominal X-Ray in the Differential Diagnosis of Common Acute Abdominal Conditions in Children at Olabisi Onabanjo University Teaching Hospital, Sagamu, Ogun State, Nigeria
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作者 Nwokoro Chigbundu Collins Olatunji Ayodeji Anike +4 位作者 Adekanmbi Abiodun Folashade Amosu Lukmon Olusesan Ogundele Olufemi Ibukunolu Olarewaju Olufunke Yetunde Oyelekan Abimbola Adeola 《Open Journal of Radiology》 2023年第3期125-133,共9页
Background: The plain abdominal x-ray is one of the commonly requested investigations in the children emergency room, paediatric surgical ward and neonatal wards. The short interval required to carry out this investig... Background: The plain abdominal x-ray is one of the commonly requested investigations in the children emergency room, paediatric surgical ward and neonatal wards. The short interval required to carry out this investigative procedure and obtain results makes it the first imaging modality used to unravel the different causes of acute abdominal conditions in children. The safety of abdominal x-ray in children makes it attractive for use in paediatric surgical practice as part of routine work-up for undifferentiated acute abdominal conditions and also to diagnose specific causes of acute abdomen in children. Setting: Olabisi Onabanjo University Teaching Hospital, Sagamu, Ogun State. Objectives: Evaluation of the role of plain abdominal x-ray in diagnosing common acute abdominal conditions in children. Materials and method: Patients admitted to the children emergency room, paediatric surgical wards, children’s ward and neonatal ward who had plain abdominal x-ray as part of their diagnostic work-up were included in the study. They were studied prospectively between March 2011 and April 2021. Results: Three Hundred and Ninety-nine patients who had plain abdominal x-rays as part of their diagnostic work-up were studied. Males were 240 while females were 159, a male to female ratio of 1.5:1. The patients were aged between 1 day to 16 years. Differential diagnoses made with plain abdominal x-ray were intestinal obstruction in 298, perforated viscus 69 patients, intra-abdominal masses 13 patients and location of intra-abdominal foreign body 14. Intestinal obstruction cases in which plain abdominal x-ray played a role in their diagnosis and management included the following: intussusception 66, neonatal sepsis 60, malrotation 48, intestinal atresia 42, anorectal malformation 32, hirschsprung’s disease in 30 cases, pyloric stenosis 24, obstructed hernia 22, post-operative adhesions 16 and intestinal helminthiasis 12. Perforated viscus accounted for 69 indications. Out of these indications, perforated gut in intussusception 19, perforated typhoid ileitis was responsible in 13 cases, gut perforation in blunt abdominal trauma 8, perforation in strangulated hernia 11 cases, perforated gut in malrotation 7, ceacal perforation in hirschsprugs disease 6 and colonic perforation in necrotizing enterocolitis 5 cases. Conclusion: Plain abdominal x-ray remains a role to play in the differential diagnosis and management of common paediatric acute abdominal conditions. 展开更多
关键词 PLAIN ABDOMINAL x-ray differential Diagnosis ACUTE Abdominal Conditions CHILDREN
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A new method of detecting interferogram in differential phase-contrast imaging system based on special structured x-ray scintillator screen 被引量:6
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作者 刘鑫 郭金川 牛憨笨 《Chinese Physics B》 SCIE EI CAS CSCD 2010年第7期193-197,共5页
An x-ray scintillator screen with a special structure, functioning as detector and analyser grating, was proposed for collecting the interferogram of differential phase contrast imaging without absorption grating and ... An x-ray scintillator screen with a special structure, functioning as detector and analyser grating, was proposed for collecting the interferogram of differential phase contrast imaging without absorption grating and difficulty of fabrication by a state of the art technique. On the basis of phase grating diffraction, a detecting model of the scintillator screen was built for analysing the phase and absorption information of objects. According to the analysis, a new method of phase retrievals based on two-images and the optimal structure of screen were presented. 展开更多
关键词 differential phase contrast x-ray scintillator screen phase retrieval
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Time-resolved K-shell x-ray spectra of nanosecond laser-produced titanium tracer in gold plasmas
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作者 何贞岑 张继彦 +2 位作者 杨家敏 闫冰 胡智民 《Chinese Physics B》 SCIE EI CAS CSCD 2023年第1期51-55,共5页
A study of a nanosecond laser irradiation on the titanium-layer-buried gold planar target is presented. The timeresolved x-ray emission spectra of titanium tracer are measured by a streaked crystal spectrometer. By co... A study of a nanosecond laser irradiation on the titanium-layer-buried gold planar target is presented. The timeresolved x-ray emission spectra of titanium tracer are measured by a streaked crystal spectrometer. By comparing the simulated spectra obtained by using the FLYCHK code with the measured titanium spectra, the temporal plasma states, i.e.,the electron temperatures and densities, are deduced. To evaluate the feasibility of using the method for the characterization of Au plasma states, the deduced plasma states from the measured titanium spectra are compared with the Multi-1D hydrodynamic simulations of laser-produced Au plasmas. By comparing the measured and simulated results, an overall agreement for the electron temperatures is found, whereas there are deviations in the electron densities. The experiment–theory discrepancy may suggest that the plasma state could not be well reproduced by the Multi-1D hydrodynamic simulation, in which the radial gradient is not taken into account. Further investigations on the spectral characterization and hydrodynamic simulations of the plasma states are needed. All the measured and FLYCHK simulated spectra are given in this paper as datasets. The datasets are openly available at http://www.doi.org/10.57760/sciencedb.j00113.00032. 展开更多
关键词 nanosecond laser irradiation time-resolved x-ray spectra characterization of plasma states Multi-1D hydrodynamic simulations
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On the Spectra of General Ordinary Quasi-Differential Operators and Their L2w-Solutions
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作者 Sobhy El-Sayed Ibrahim 《Advances in Pure Mathematics》 2022年第3期186-205,共20页
In this paper, we consider the general ordinary quasi-differential expression τ of order n with complex coefficients and its formal adjoint τ<sup>+</sup> on the interval [a,b). We shall show in the case ... In this paper, we consider the general ordinary quasi-differential expression τ of order n with complex coefficients and its formal adjoint τ<sup>+</sup> on the interval [a,b). We shall show in the case of one singular end-point and under suitable conditions that all solutions of a general ordinary quasi-differential equation are in the weighted Hilbert space provided that all solutions of the equations and its adjoint are in . Also, a number of results concerning the location of the point spectra and regularity fields of the operators generated by such expressions may be obtained. Some of these results are extensions or generalizations of those in the symmetric case, while the others are new. 展开更多
关键词 General Ordinary Quasi-differential Expressions Regular and Singular End-Points Singular differential Operators Essential spectra Point spectra and Regularity Fields
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Measurement of tungsten impurity spectra with a two-crystal X-ray crystal spectrometer on EAST
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作者 Liang HE Jun CHEN +12 位作者 Fudi WANG Jinjia CAO Hongming ZHANG Jia FU Yingying LI Yichao LI Bin BIN Qingjiang YU Shunkuan WAN Jin YANG Xunyu WANG Bo LYU Xueyu GONG 《Plasma Science and Technology》 SCIE EI CAS CSCD 2020年第8期14-19,共6页
Spectral measurement of tungsten(W)impurity is essential to study impurity transport.Therefore,an X-ray crystal spectrometer(XCS)on EAST was used to measure the line spectra from highly ionized W ions.On EAST,both pol... Spectral measurement of tungsten(W)impurity is essential to study impurity transport.Therefore,an X-ray crystal spectrometer(XCS)on EAST was used to measure the line spectra from highly ionized W ions.On EAST,both poloidal XCS and tangential XCS have been developed to measure the plasma temperature as well as the rotation velocity.Recently,He-like and H-like argon spectra have also been obtained using a two-crystal setup.W lines are identified in this study.Through a careful analysis,the W lines of 3.9336,3.9321,and 3.664(A)are found to be diffracted by He-like or H-like crystals.The lines are confirmed with the NIST database.We also calculated the ion temperature with Doppler broadening of these lines.The ion temperature from the W lines is entirely consistent with that from Ar line spectra.The measurement of these W line spectra could be used to study W impurity transport in future work. 展开更多
关键词 TUNGSTEN spectra x-ray CRYSTAL SPECTROMETER two-crystal
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On High-Frequency Soliton Solutions to a (2+1)-Dimensional Nonlinear Partial Differential Evolution Equation
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作者 Kuetche Kamgang Victor Bouetou Bouetou Thomas Timoleon Crepin Kofane 《Chinese Physics Letters》 SCIE CAS CSCD 2008年第2期425-428,共4页
A (2+1)-dimensional nonlinear partial differential evolution (NLPDE) equation is presented as a model equation for relaxing high-rate processes in active barothropic media. With the aid of symbolic computation an... A (2+1)-dimensional nonlinear partial differential evolution (NLPDE) equation is presented as a model equation for relaxing high-rate processes in active barothropic media. With the aid of symbolic computation and Hirota's method, some typical solitary wave solutions to this (2+1)-dimensional NLPDE equation are unearthed. As a result, depending on the dissipative parameter, single and multivalued solutions are depicted. 展开更多
关键词 PULSARS x-ray spectra relativity and gravitation REDSHIFT
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X-ray spectra of high temperature tungsten plasma calculated with collisional radiative model
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作者 王君 张红 程新路 《Chinese Physics B》 SCIE EI CAS CSCD 2013年第8期514-518,共5页
Tungsten is regarded as an important candidate of plasma facing material in international thermonuclear experimental reactor (ITER), so the determination and modeling of spectra of tungsten plasma, especially the sp... Tungsten is regarded as an important candidate of plasma facing material in international thermonuclear experimental reactor (ITER), so the determination and modeling of spectra of tungsten plasma, especially the spectra at high temperature were intensely focused on recently. In this work, using the atomic structure code of Cowan, a collisional radiative model (CRM) based on the spin-orbit-split-arrays is developed. Based on this model, the charge state distribution of tungsten ions is determined and the soft X-ray spectra from high charged ions of tungsten at different temperatures are calculated. The results show that both the average ionization charge and line positions are well agreed with others calculations and measurements with discrepancies of less than 0.63% and 1.26%, respectively. The spectra at higher temperatures are also reported and the relationship between ion abundance and temperature is predicted in this work. 展开更多
关键词 tungsten plasma high temperature x-ray spectra collisional radiative model
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A Simulation Study on the Flash X-Ray Spectra Spatial Distribution
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作者 徐修峰 李世平 +4 位作者 曹宏睿 肖锐 陈楠 章林文 阴泽杰 《Plasma Science and Technology》 SCIE EI CAS CSCD 2013年第11期1165-1168,共4页
Accurate measurement of flash X-ray energy spectra plays an important role in highenergy flash radiography. In this paper, by virtue of Geant4 toolkit, we simulated the generation and transport of X-ray photons result... Accurate measurement of flash X-ray energy spectra plays an important role in highenergy flash radiography. In this paper, by virtue of Geant4 toolkit, we simulated the generation and transport of X-ray photons resulting from the interaction of a high-energy electron beam with a solid thin target. We obtained the flash X-ray energy spectral distribution in the plane perpendicular to the electron beam incident direction. Our results indicate that the flash X- ray spectrum is almost uniform in the azimuthal direction but is quite different in the radius direction. Specifically, as the radius increases, the incident X-ray dose decreases significantly. Our work paves a theoretical basis for selecting appropriate structures and layout of the spectrometer and facilitates the measurements of flash X-ray energy spectra. 展开更多
关键词 GEANT4 flash x-ray spectra spatial distribution
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Alpha-actinin expression at different differentiating time points from temporal lobe cerebral cortex neural stem cells to neuron-like cells using energy dispersive X-ray analysis
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作者 Bo Yu Hua Li +3 位作者 Zhe Du Yang Hong Meng Sang Yuxiu Shi 《Neural Regeneration Research》 SCIE CAS CSCD 2009年第4期265-270,共6页
BACKGROUND: Alpha-actinin ( a -actinin) plays a key role in neuronal growth cone migration during directional differentiation from neural stem cells (NSCs) to neurons. OBJECTIVE: To detect in situ microdistribut... BACKGROUND: Alpha-actinin ( a -actinin) plays a key role in neuronal growth cone migration during directional differentiation from neural stem cells (NSCs) to neurons. OBJECTIVE: To detect in situ microdistribution and quantitative expression of a -actinin during directional differentiation of NSCs to neurons in the temporal lobe cerebral cortex of neonatal rats. DESIGN, TIME AND SETTING: Between January 2006 and December 2008, culture and directional differentiation of NSCs were performed at Department of Histology and Embryology, Preclinical Medical College, China Medical University. Immune electron microscopy was performed at Department of Histology and Embryology and Department of Electron Micrology, Preclinical Medical College, China Medical University. Spectrum analysis was performed at Laboratory of Electron Microscopy, Mental Research Institute, Chinese Academy of Sciences. MATERIALS: Basic fibroblast growth factor, epidermal growth factor, brain-derived nerve growth factor, type-1 insulin like growth factor, and a -actinin antibody were provided by Gibco BRL, USA; rabbit-anti-rat nestin monoclonal antibody, rabbit-anti-rat neuron specific enolase polyclonal antibody, and EDAX-9100 energy dispersive X-ray analysis were provided by PHILIPS Company, Netherlands. METHODS: NSCs, following primary and passage culture, were differentiated with serum culture medium (DMEM/F12 + 10% fetal bovine serum + 2 ng/mL brain-derived nerve growth factor + 2 ng/mL type-1 insulin like growth factor). MAIN OUTCOME MEASURES: Expression of a -actinin in neuron-like cells was quantitatively and qualitatively detected with immunocytochemistry using energy dispersive X-ray analysis. RESULTS: Immunocytochemistry, combined with electron microscopy, indicated that positive α -actinin expression was like a spheroid particle with high electron density. In addition, the expression was gradually concentrated from the nuclear edge to the cytoplasm and expanded into developing neurites, during differentiation of neural stem cells to neurons. Conversely, energy dispersive X-ray analysis indicated that the more mature the neural differentiation was, and the greater the expression of α -actinin. CONCLUSION: The gradual increase of α -actinin expression is related to growth, development, and maturity of differentiated neuron-like cells, in neonatal rat frontal lobe cortex, at different differentiating time points of NSCs to neurons. 展开更多
关键词 energy dispersive x-ray analysis a -actinin neural stem cells directional differentiation NEURONS
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Blue-shift of Nano-Y_2O_3 : Eu^(3+) Emission Spectra Excited by X-ray
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作者 Qiang LI Lian GAO and Dongsheng YAN(State Key Lab. of High Performance Ceramics & Superfine Microstructure, Shanghai Institute of Ceramics,Chinese Academy of Sciences, Shanghai 200050, China) 《Journal of Materials Science & Technology》 SCIE EI CAS CSCD 1997年第4期351-353,共3页
Nano-Y_2O_3:Eu^(3+) powder was prepared by the homogeneous precipitation. With controlling the conditions of the reaction, nano powders with different grain size were obtained. It is found that the blue-shift phenomen... Nano-Y_2O_3:Eu^(3+) powder was prepared by the homogeneous precipitation. With controlling the conditions of the reaction, nano powders with different grain size were obtained. It is found that the blue-shift phenomena exist in the nano-Y2O3:Eu3+ emission spectra excited by X-ray. The wave lengths of the peak (5D0→7F2) are related with the grain size of the powder 展开更多
关键词 EU NANO Emission spectra Excited by x-ray Blue-shift of Nano-Y2O3
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Analysis of the X-ray emission from OB stars Ⅲ: low-resolution spectra of OB stars
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作者 Elizaveta Ryspaeva Alexander Kholtygin 《Research in Astronomy and Astrophysics》 SCIE CAS CSCD 2020年第7期161-171,共11页
This paper is the third in our series of papers devoted to the investigation of X-ray emission from OB stars.In our two previous papers,we study the high-resolution X-ray spectra of 32 O stars and 25 B stars to invest... This paper is the third in our series of papers devoted to the investigation of X-ray emission from OB stars.In our two previous papers,we study the high-resolution X-ray spectra of 32 O stars and 25 B stars to investigate the correlations between the properties of X-ray emission and stellar parameters.We checked if the X-ray hardness and post-shock plasma temperature grow with increasing stellar magnetic field,mass loss rate and terminal wind velocity.Our previous analysis of high-resolution spectra showed that the correlations are weak or even absent.In the present paper,we analyzed low-resolution X-ray spectra,using model-independent X-ray hardness values for checking the above mentioned dependencies.We establish that X-ray luminosities LX weakly depend on the stellar magnetic field.At the same time,Lx ∝ M0.5 and LX ∝ Ekin0.5,where M is the mass loss rate and Ekin is the kinetic energy of the wind.The X-ray luminosities decrease with growing magnetic confinement parameter η.We also argue that there is an additional(probably non-thermal) component contributed to the stellar X-ray emission. 展开更多
关键词 stars:early-type stars:spectra:x-ray
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X-RAY FLUORESCENCE SPECTRA ANALYSIS ON THE STRUCTURE AROUND Ti^(4+) OF BaO-SiO_2-B_2O_3-TiO_2 SYSTEM GLASSES
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作者 宋晓岚 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS 2000年第4期43-47,共5页
The structure around Ti^(4+) in Bao-SiO_2 -B_2O_3-TiO_2 had been studied by X-ray fluorescence spectra. The results show that the Ti^(4+) mainly exists in the [TiO_4] and enters the network of [SiO_4]. [TiO_4] has the... The structure around Ti^(4+) in Bao-SiO_2 -B_2O_3-TiO_2 had been studied by X-ray fluorescence spectra. The results show that the Ti^(4+) mainly exists in the [TiO_4] and enters the network of [SiO_4]. [TiO_4] has the tendency to change to [TiO_6] with the increase of TiO_2 con-tent. When the TiO_2 content increases to about 20mol% the tendency reaches its maximum. 展开更多
关键词 titanium barium boronsilicate glasses Ti^(4+) structural state x-ray fluorescence spectra analysis (XRF)
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X-Ray and VUV Spectra from the Laser Plasma Produced with “Kanal-2” Facility
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作者 Andrey Aleksandrovich Kologrivov Mikhail Vladimirovich Osipov +2 位作者 Victor Nikolaevich Puzyrev Alexandr Nikolaevich Starodub Oleg Feliksovich Yakushev 《Journal of Modern Physics》 2014年第2期92-97,共6页
The paper presents experimental results obtained on “Kanal-2” facility. Laser radiation focusing on the surface of plane magnesium targets created the high temperature plasma, which emitted X-ray and vacuum ultravio... The paper presents experimental results obtained on “Kanal-2” facility. Laser radiation focusing on the surface of plane magnesium targets created the high temperature plasma, which emitted X-ray and vacuum ultraviolet (VUV) radiation. This radiation spectrum was investigated with two spectrographs: the mica crystal spectrograph (working range 8.2 ? - 9.6 ?) and the grazing incidence VUV spectrograph (working rage 30 ? - 130 ?). A set of beryllium stepwise attenuators appended the diagnostic complex and allowed us to get an approximated picture of a continuous spectrum within the range of 2.2 ? - 6.2 ?. The estimation of the plasma electron temperature Te from the ratio between the intensity of the dielectronic satellites and the resonance line gives Te ~ 180 eV. The ratio between the intensity of the resonance and intercombination lines gives the electron density of the emitting zone ne ~ 2 × 1019 cm-3. Some lines observed within the spectral range of 8.5 ? - 9.1 ? belong to none of the transitions of Mg ions. Perhaps the observed spectrum is determined by the transitions in so-called hollow ions of Mg, i.e. in the ions with unfilled inner shells. The spectra obtained with the grazing incidence spectrograph and with the minimum-directioned discrepancy iteration method of spectrum reconstruction from the attenuation curve in the beryllium stepwise attenuators are also presented. 展开更多
关键词 Laser PLASMA x-ray spectra VUV spectra PLASMA DIAGNOSTICS
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Elemental composition x-ray fluorescence analysis with a TES-based high-resolution x-ray spectrometer
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作者 吴秉骏 夏经铠 +4 位作者 张硕 傅强 章辉 谢晓明 刘志 《Chinese Physics B》 SCIE EI CAS CSCD 2023年第9期67-73,共7页
The accurate analysis of the elemental composition plays a crucial role in the research of functional materials.The emitting characteristic x-ray fluorescence(XRF)photons can be used for precisely discriminating the s... The accurate analysis of the elemental composition plays a crucial role in the research of functional materials.The emitting characteristic x-ray fluorescence(XRF)photons can be used for precisely discriminating the specified element.The detection accuracy of conventional XRF methodology using semiconductor detector is limited by the energy resolution,thus posing a challenge in accurately scaling the actual energy of each XRF photon.We adopt a novel high-resolution x-ray spectrometer based on the superconducting transition-edge sensor(TES)for the XRF spectroscopy measurement of different elements.Properties including high energy resolution,high detection efficiency and precise linearity of the new spectrometer will bring significant benefits in analyzing elemental composition via XRF.In this paper,we study the Ledge emission line profiles of three adjacent rare earth elements with the evenly mixed sample of their oxide components:terbium,dysprosium and holmium.Two orders of magnitude better energy resolution are obtained compared to a commercial silicon drift detector.With this TES-based spectrometer,the spectral lines overlapped or interfered by background can be clearly distinguished,thus making the chemical component analysis more accurate and quantitative.A database of coefficient values for the line strength of the spectrum can then be constructed thereafter.Equipped with the novel XRF spectrometer and an established coefficient database,a direct analysis of the composition proportion of a certain element in an unknown sample can be achieved with high accuracy. 展开更多
关键词 x-ray emission spectra and fluorescence superconducting transition-edge sensor rare earth elements chemical composition analysis
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 ̄(151)Eu-MOSSBAUER SPECTRA AND XPS INVESTIGATION OF BaFBr:Eu PHOSPHOR
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作者 陈伟 宋家庆 苏勉曾 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS CSCD 1995年第2期103+97-103,共8页
Eu Mossbauer spectra of BaFBr:Eu phosphor are reported for the first time.The results show that f(Eu(2+) )<f(Eu(3+)) or <x2>Eu(2+)><x2>Eu(3+),which indicates that the attraction between phonons and E... Eu Mossbauer spectra of BaFBr:Eu phosphor are reported for the first time.The results show that f(Eu(2+) )<f(Eu(3+)) or <x2>Eu(2+)><x2>Eu(3+),which indicates that the attraction between phonons and Eu(2+) is stronger than that between phonons and Eu(3+),this may cause a faster increase of f(Eu=(2+)vs f(Eu(3+)) when temperature decreases as observed in the experiments.It is also found from Mossbauer investigation that when temperature decreases,the relative content of Eu(2+) decreases, while that of Eu(3+) increases.The temperature dependent Mossbauer spectra provide evidence for electron exchange or hopping between Eu(2+) or Eu(3+) sites in BaFBr lattice. The Mossbauer results are discussed and compared with the results of XPS and Photoluminescence studies. 展开更多
关键词 BaFBr:Eu phosphor Mossbauer spectra emission spectra x-ray photoelectron spectra
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Construction of a predictive model for gastric cancer neuroaggression and clinical validation analysis: A single-center retrospective study
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作者 Yu-Yin Lan Jing Han +1 位作者 Yan-Yan Liu Lei Lan 《World Journal of Gastrointestinal Surgery》 SCIE 2024年第8期2602-2611,共10页
BACKGROUND This study investigated the construction and clinical validation of a predictive model for neuroaggression in patients with gastric cancer.Gastric cancer is one of the most common malignant tumors in the wo... BACKGROUND This study investigated the construction and clinical validation of a predictive model for neuroaggression in patients with gastric cancer.Gastric cancer is one of the most common malignant tumors in the world,and neuroinvasion is the key factor affecting the prognosis of patients.However,there is a lack of systematic analysis on the construction and clinical application of its prediction model.This study adopted a single-center retrospective study method,collected a large amo-unt of clinical data,and applied statistics and machine learning technology to build and verify an effective prediction model for neuroaggression,with a view to providing scientific basis for clinical treatment decisions and improving the tr-eatment effect and survival rate of patients with gastric cancer.AIM To investigate the value of a model based on clinical data,spectral computed to-mography(CT)parameters and image omics characteristics for the preoperative prediction of nerve invasion in patients with gastric cancer.METHODS A retrospective analysis was performed on 80 gastric cancer patients who under-went preoperative energy spectrum CT at our hospital between January 2022 and August 2023,these patients were divided into a positive group and a negative group according to their pathological results.Clinicopathological data were collected,the energy spectrum parameters of primary gastric cancer lesions were measured,and single factor analysis was performed.A total of 214 image omics features were extracted from two-phase mixed energy images,and the features were screened by single factor analysis and a support vector machine.The variables with statist-ically significant differences were included in logistic regression analysis to construct a prediction model,and the performance of the model was evaluated using the subject working characteristic curve.There were statistically significant differences in sex,carbohydrate antigen 199 expression,tumor thickness,Lauren classification and Borrmann classification between the two groups(all P<0.05).Among the energy spectrum parameters,there were statistically significant differences in the single energy values(CT60-CT110 keV)at the arterial stage between the two groups(all P<0.05)and statistically significant differences in CT values,iodide group values,standardized iodide group values and single energy values except CT80 keV at the portal vein stage between the two groups(all P<0.05).The support vector machine model with the largest area under the curve was selected by image omics analysis,and its area under the curve,sensitivity,specificity,accuracy,P value and pa-rameters were 0.843,0.923,0.714,0.925,<0.001,and c:g 2.64:10.56,respectively.Finally,based on the logistic regression algorithm,a clinical model,an energy spectrum CT model,an imaging model,a clinical+energy spe-ctrum model,a clinical+imaging model,an energy spectrum+imaging model,and a clinical+energy spectrum+imaging model were established,among which the clinical+energy spectrum+imaging model had the best efficacy in diagnosing gastric cancer nerve invasion.The area under the curve,optimal threshold,Youden index,sensitivity and specificity were 0.927(95%CI:0.850-1.000),0.879,0.778,0.778,and 1.000,respectively.CONCLUSION The combined model based on clinical features,spectral CT parameters and imaging data has good value for the preoperative prediction of gastric cancer neuroinvasion. 展开更多
关键词 Gastric neoplasms Nerve invasion TOMOGRAPHY x-ray computer Imaging omics Diagnostic differentiation
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X-ray volumetric quantitative phase imaging by Foucault differential filtering with linear scanning
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作者 Young-Sung Park Jieun Hong Jaeho Choi 《Chinese Optics Letters》 SCIE EI CAS CSCD 2023年第1期120-124,共5页
Non-interferometric X-ray quantitative phase imaging(XQPI),much simpler than the interferometric scheme,has provided high-resolution and reliable phase-contrast images.We report on implementing the volumetric XQPI ima... Non-interferometric X-ray quantitative phase imaging(XQPI),much simpler than the interferometric scheme,has provided high-resolution and reliable phase-contrast images.We report on implementing the volumetric XQPI images using concurrent-bidirectional scanning of the orthogonal plane on the optical axis of the Foucault differential filter;we then extracted data in conjunction with the transport-intensity equation.The volumetric image of the laminate microstructure of the gills of a fish was successfully reconstructed to demonstrate our XQPI method.The method can perform 3D rendering without any rotational motion for laterally extended objects by manipulating incoherent X-rays using the pinhole array. 展开更多
关键词 x-ray imaging phase contrast imaging Foucault differential filter transport-intensity equation
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The development,performances and applications of the monochromatic X-rays facilities in(0.218–301)keV at NIM,China 被引量:5
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作者 Si-Ming Guo Jin-Jie Wu Dong-Jie Hou 《Nuclear Science and Techniques》 SCIE EI CAS CSCD 2021年第6期108-121,共14页
Space scientific exploration is rapidly becoming the primary battlefield for humankind to explore the universe.Countries worldwide have launched numerous space exploration satellites.Accurate calibration of the detect... Space scientific exploration is rapidly becoming the primary battlefield for humankind to explore the universe.Countries worldwide have launched numerous space exploration satellites.Accurate calibration of the detectors on the ground is a crucial element for space science satellites to obtain observational results.For the purpose of providing calibration for various satellite-borne detectors,multiple monochromatic X-rays facilities have been built at the National Institute of Metrology,P.R.China(NIM).These facilities mainly pertain to grating diffraction and Bragg diffraction,and the energy range of the produced monochromatic X-rays is 0.218–301 ke V.These facilities have a high performance in terms of energy stability,monochromaticity,and flux stability.The monochromaticity was greater than 3.0%.The energy stability of the facility is 0.02%at 25 ke V over 8 h,and the flux stability was within 1.0%at 25 ke V over 8 h.Calibration experiments on the properties of satellite-borne detectors,such as energy linearity,energy resolution,detection efficiency,and temperature response,can be conducted at the facilities.Thus far,the calibration of two satellites has been completed by the authors,and the work on three other satellites is in progress.This study will contribute to the advancement of X-ray astronomy the development of Chinese space science. 展开更多
关键词 Monochromatic x-rays MONOCHROMATOR Bragg diffraction Energy spectra Calibration
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Generation of an isolated sub-100 attosecond pulse in the water-window spectral region 被引量:3
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作者 邹璞 李儒新 +5 位作者 曾志男 熊辉 刘鹏 冷雨欣 范品忠 徐至展 《Chinese Physics B》 SCIE EI CAS CSCD 2010年第1期589-594,共6页
We propose a scheme to generate isolated attosecond pulses in the water-window spectral region. Based on the numerical solutions of the single active electron model, we investigate high-order harmonic generation in he... We propose a scheme to generate isolated attosecond pulses in the water-window spectral region. Based on the numerical solutions of the single active electron model, we investigate high-order harmonic generation in helium atoms driven by a multi-cycle two-colour optical field synthesized by an intense 2000 nm, 20 fs pulse and its frequency-doubled pulse. When the latter is slightly detuned and properly phase shifted with respect to the fundamental laser pulse, an ultra-broad extreme ultraviolet supercontinuum with a spectral width of 130 eV can be generated in the 270 400 eV spectral regions. A supercontinuum from 280-340 eV in the water window can be selected to yield an isolated 67 attosecond pulse without employing any phase compensation. This water window coherent x-ray pulse with less than 100 attosecond duration is a potential tool for studying the ultrafast electronic dynamics of biological samples in water. 展开更多
关键词 x-ray ultraviolet spectra optical harmonic generation
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