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First Born Double Differential Cross-Section for Ionization of H (3d) by Incident Electron Impact
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作者 Sushmita Banerjee Sunil Dhar 《Open Journal of Microphysics》 2024年第2期67-77,共11页
Double differential cross section (DDCS) of First-Born approximation is calcu-lated for the ionization of metastable 3d-state hydrogen atoms by electron impact energy at 150 eV and 250 eV. A multiple scattering theory... Double differential cross section (DDCS) of First-Born approximation is calcu-lated for the ionization of metastable 3d-state hydrogen atoms by electron impact energy at 150 eV and 250 eV. A multiple scattering theory is applied in the present study. The present results are compared with the other related the-oretical results for the ionization of hydrogen atoms from different metastable states and ground-state experimental results. The findings demonstrate a strong qualitative agreement with the existing results. The obtained results have an extensive scope for further study of such an ionization process. 展开更多
关键词 Electron IONIZATION cross-section scattering
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Oscillator strength and cross section study of the valence-shell excitations of NO_(2) by fast electron scattering
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作者 孙强 陈锦峰 +2 位作者 聂智伟 朱剑辉 朱林繁 《Chinese Physics B》 SCIE EI CAS CSCD 2023年第11期201-206,共6页
Oscillator strengths and cross sections of the valence-shell excitations in NO_(2)are of great significance in testing the theoretical calculations and monitoring the state of the ozone layer in the earth’s atmospher... Oscillator strengths and cross sections of the valence-shell excitations in NO_(2)are of great significance in testing the theoretical calculations and monitoring the state of the ozone layer in the earth’s atmosphere. In the present work, the generalized oscillator strengths of the valence-shell excitations in NO_(2)were obtained based on the fast electron scattering technique at an incident electron energy of 1.5 ke V and an energy resolution of about 70 me V. By extrapolating the generalized oscillator strengths to the limit of a zero squared momentum transfer, the optical oscillator strengths for the dipole-allowed transitions have been obtained, which provide an independent cross check to the previous experimental results. Based on the BE-scaling method, the corresponding integral cross sections have also been derived systematically from the excitation threshold to 5000 eV. The present dynamic parameters can provide the fundamental spectroscopic data of NO_(2)and have important applications in the studies of atmospheric science. The datasets presented in this paper, including the GOSs, OOSs and ICSs, are openly available at https://doi.org/10.57760/sciencedb.j00113.00156. 展开更多
关键词 nitrogen dioxide oscillator strength integral cross section electron scattering
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Double Differential Cross-Section for the Ionization of Hydrogenic 2S Metastable State
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作者 Md. Thowhidul Hoque Chowdhury Sunil Dhar 《Open Journal of Microphysics》 CAS 2023年第1期1-13,共13页
Double differential cross-sections of first Born estimation for ionization of hydrogenic 2S state by electrons are assessed for various kinematics situations in the asymmetric coplanar geometry. A final state wave fun... Double differential cross-sections of first Born estimation for ionization of hydrogenic 2S state by electrons are assessed for various kinematics situations in the asymmetric coplanar geometry. A final state wave function of multiple scattering theory is followed in this study. The present outcomes are compared with those of hydrogenic ground state, 2P state and ground state experimental results. Obtained findings show a good qualitative agreement with existing results. 展开更多
关键词 HYDROGEN IONIZATION Double differential cross-section METASTABLE scattering
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State-selective charge exchange cross sections in collisions of highly-charged sulfur ions with helium and molecular hydrogen
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作者 朱小龙 崔述成 +9 位作者 邢大地 徐佳伟 B.Najjari 赵冬梅 郭大龙 高永 张瑞田 苏茂根 张少锋 马新文 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第2期29-33,共5页
The state-selective cross section data are useful for understanding and modeling the x-ray emission in celestial observations.In the present work,using the cold target recoil ion momentum spectroscopy,for the first ti... The state-selective cross section data are useful for understanding and modeling the x-ray emission in celestial observations.In the present work,using the cold target recoil ion momentum spectroscopy,for the first time we investigated the state-selective single electron capture processes for S^(q+)–He and H_(2)(q=11–15)collision systems at an impact energy of q×20 keV and obtained the relative state-selective cross sections.The results indicate that only a few principal quantum states of the projectile energy level are populated in a single electron capture process.In particular,the increase of the projectile charge state leads to the population of the states with higher principal quantum numbers.It is also shown that the experimental averaged n-shell populations are reproduced well by the over-barrier model.The database is openly available in Science Data Bank at 10.57760/sciencedb.j00113.00091. 展开更多
关键词 highly charged sulfur ion charge exchange state-selective cross sections COLTRIMS
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Absolute partial and total ionization cross sections of carbon monoxide with electron collision from 350 eV to 8000 eV
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作者 Taj Wali Khan 黄伟哲 +2 位作者 王恩亮 单旭 陈向军 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第4期459-464,共6页
The absolute partial and total cross sections for electron impact ionization of carbon monoxide are reported for electron energies from 350 eV to 8000 eV.The product ions(CO^(+),C^(+),O^(+),CO^(2+),C^(2+),and O^(2+))a... The absolute partial and total cross sections for electron impact ionization of carbon monoxide are reported for electron energies from 350 eV to 8000 eV.The product ions(CO^(+),C^(+),O^(+),CO^(2+),C^(2+),and O^(2+))are measured by employing an ion imaging mass spectrometer and two ion-pair dissociation channels(C^(+)+O^(+)and C^(2+)+O^(+))are identified.The absolute cross sections for producing individual ions and their total,as well as for the ion-pair dissociation channels are obtained by normalizing the data of CO^(+)to that of Ar^(+)from CO-Ar mixture target with a fixed 1:1 ratio.The overall errors are evaluated by considering various kinds of uncertainties.A comprehensive comparison is made with the available data,which shows a good agreement with each other over the energy ranges that are overlapped.This work presents new cross-section data with electron energies above 1000 eV. 展开更多
关键词 electron impact ionization cross sections carbon monoxide ion imaging mass spectrometer
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Measurement of the neutron-induced total cross sections of ^(nat)Pb from 0.3 eV to 20 MeV on the Back-n at CSNS
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作者 Jie-Ming Xue Song Feng +14 位作者 Yong-Hao Chen Han Yi Min Xiao Pin-Jing Cheng Xin-Xiang Li Rong Liu Yi-Wei Yang Zi-Jie Han Da-Jun Zhao Hao-Qiang Wang Bao-Qian Li Ji-Rong Zhao Lei-Xun Tang Wen Luo Bo Zheng 《Nuclear Science and Techniques》 SCIE EI CAS CSCD 2024年第2期85-93,共9页
The neutron-induced total cross sections of natural lead have been measured in a wide energy range(0.3 eV-20 MeV)on the back-streaming white neutron beamline(Back-n)at the China Spallation Neutron Source.Neutron energ... The neutron-induced total cross sections of natural lead have been measured in a wide energy range(0.3 eV-20 MeV)on the back-streaming white neutron beamline(Back-n)at the China Spallation Neutron Source.Neutron energy was determined by the neutron total cross-section spectrometer using the time-of-flight technique.A fast multi-cell fission chamber was used as the neutron detector,and a 10-mm-thick high-purity natural lead sample was employed for the neutron transmission measurements.The on-beam background was determined using Co,In,Ag,and Cd filters.The excitation function of ^(nat)Pb(n,tot)reaction below 20 MeV was calculated using the TALYS-1.96 nuclear-reaction modeling program.The present results were compared with previous results,the evaluated data available in the five major evaluated nuclear data libraries(i.e.,ENDF/B-VIII.0,JEFF-3.3,JENDL-5,CENDL-3.2,and BROND-3.1),and the theoretical calculation curve.Good agreement was found between the new results and those of previous experiments and with the theoretical curves in the corresponding region.This measurement obtained the neutron total cross section of natural lead with good accuracy over a wide energy range and added experimental data in the resonance energy range.This provides more reliable experimental data for nuclear engineering design and nuclear data evaluation of lead. 展开更多
关键词 Neutron-induced total cross section Natural lead TIME-OF-FLIGHT TALYS-1.96 CSNS Back-n white neutron beamline
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Oscillatory Dynamics of a Spherical Solid in a Liquid in an Axisymmetric Variable Cross Section Channel
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作者 Ivan Karpunin 《Fluid Dynamics & Materials Processing》 EI 2024年第6期1219-1232,共14页
The dynamics of a solid spherical body in an oscillating liquid flow in a vertical axisymmetric channel of variable cross section is experimentally studied.It is shown that the oscillating liquid leads to the generati... The dynamics of a solid spherical body in an oscillating liquid flow in a vertical axisymmetric channel of variable cross section is experimentally studied.It is shown that the oscillating liquid leads to the generation of intense averaged flows in each of the channel segments.The intensity and direction of these flows depend on the dimensionless oscillating frequency.In the region of studied frequencies,the dynamics of the considered body is examined when the primary vortices emerging in the flow occupy the whole region in each segment.For a fixed frequency,an increase in the oscillation amplitude leads to a phase-inclusion holding effect,i.e.,the body occupies a quasi-stationary position in one of the cells of the vertical channel,while oscillating around its average position.It is also shown that the oscillating motion of a liquid column generates an averaged force acting on the body,the magnitude of which depends on the properties of the body and its position in the channel.The quasi-stationary position is determined by the relative density and size of the body,as well as the dimensionless frequency.The behavior of the body as a function of the amplitude and frequency of fluid oscillation and relative size is discussed in detail.Such findings may be used in the future to control the position of a phase inclusion and/or to strengthen mass transfer effects in a channel of variable cross section by means of fluid oscillations. 展开更多
关键词 Phase inclusion axisymmetric channel variable cross section oscillations dimensionless frequency averaged force viscous boundary layer
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Cross section determination of^(27)Al(n,2n)^(26)Al reaction induced by 14-MeV neutrons uniting with D-T neutron activation and AMS techniques
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作者 Xian-Lin Yang Chang-Lin Lan +6 位作者 Yu-Ting Wei Yi Zhang Gong Jiang Bo Xie Yu Liu Hong-Tao Shen Xiao-Jun Sun 《Nuclear Science and Techniques》 SCIE EI CAS CSCD 2024年第6期78-89,共12页
Aluminum is the primary structural material in nuclear engineering,and its cross section induced by 14-MeV neutrons is of great significance.To address the issue of insufficient accuracy for the^(27)Al(n,2n)^(26)Al re... Aluminum is the primary structural material in nuclear engineering,and its cross section induced by 14-MeV neutrons is of great significance.To address the issue of insufficient accuracy for the^(27)Al(n,2n)^(26)Al reaction cross section,the activation method and accelerator mass spectrometry(AMS)technique were used to determine the^(27)Al(n,2n)^(26)Al cross section,which could be used as a D-T plasma ion temperature monitor in fusion reactors.At the China Academy of Engineering Physics,neutron activation was performed using a K-400 neutron generator produced by the T(d,n)4He reaction.The^(26)Al∕^(27)Al isotope ratios were measured using the newly installed GYIG 1 MV AMS at the Institute of Geochemistry,Chinese Academy of Sciences.The neutron flux was monitored by measuring the activity of 92mNb produced by the 93Nb(n,2n)92mNb reaction.The measured results were compared with available data in the experimental nuclear reaction database,and the measured values showed a reasonable degree of consistency with partially available literature data.The newly acquired cross-sectional data at 12 neutron energy points through systematic measurements clarified the divergence,which has two different growth trends from the existing experimental values.The obtained results are also compared with the corresponding evaluated database,and the newly calculated excitation functions with TALYS−1.95 and EMPIRE−3.2 codes,the agreement with CENDL−3.2,TENDL-2021 and EMPIRE−3.2 results are generally acceptable.A substantial improvement in the knowledge of the^(27)Al(n,2n)^(26)Al reaction excitation function was obtained in the present work,which will lay the foundation for the diagnosis of the fusion ion temperature,testing of the nuclear physics model,evaluation of nuclear data,etc. 展开更多
关键词 14-MeV neutron ^(27)Al(n 2n)^(26)Al cross section AMS
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Differential cross sections of elastic electron scattering from CH4. CF4 and SF6 in the energy range l00-700eV
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作者 马二俊 马余刚 +3 位作者 蔡翔舟 方德清 沈文庆 田文栋 《Chinese Physics B》 SCIE EI CAS CSCD 2007年第11期3339-3344,共6页
We investigate the differential cross sections (DCS) of elastic electron scattering from CH4, CF4 and SF6 at six impact energies in a range of 100 700eV by employing the independent atom model (IAM) together with ... We investigate the differential cross sections (DCS) of elastic electron scattering from CH4, CF4 and SF6 at six impact energies in a range of 100 700eV by employing the independent atom model (IAM) together with the relativistic partial waves. The atom is present in an optical potential which is complex, spherically symmetric, and energy dependent. The optical potential of the atom is the sum of the direct static, dynamic polarization, local exchange and modified absorption potentials. The results obtained by using a modified absorption potential show significant improvements on the unmodified absorption potential results. The present results are generally in good agreement with experimental data available. In addition, the present results indicate that the structure of molecule manifests the observable effects on electron- molecule scattering. 展开更多
关键词 differential cross sections independent atom model electron molecule scattering relativistic partial waves modified absorption potential
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Dyslipidemia in Adults with Type 2 Diabetes in a Rural Community in Ganadougou, Mali: A Cross-Sectional Study
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作者 Abdoulaye Diawara Djibril Mamadou Coulibaly +22 位作者 Drissa Kone Mama A. Traore Drissa Konaté Dicko S. Bazi Oumar Kassogue Djeneba Sylla Fatoumata Gniné Fofana Oudou Diabaté Mariam Traore Ibrahim Antoine Nieantao Kaly Keїta Mamadou Diarra Olivia Smith Jian Li Cheickna Cisse Talib Yusuf Abbas Crystal Zheng Segun Fatumo Kassim Traore Mamadou Wele Mahamadou Diakité Seydou O. Doumbia Jeffrey G. Shaffer 《Journal of Diabetes Mellitus》 CAS 2024年第2期133-152,共20页
Dyslipidemia is a disorder where abnormally lipid concentrations circulate in the bloodstream. The disorder is common in type 2 diabetics (T2D) and is linked with T2D comorbidities, particularly cardiovascular disease... Dyslipidemia is a disorder where abnormally lipid concentrations circulate in the bloodstream. The disorder is common in type 2 diabetics (T2D) and is linked with T2D comorbidities, particularly cardiovascular disease. Dyslipidemia in T2D is typically characterized by elevated plasma triglyceride and low high-density lipoprotein cholesterol (HDL-C) levels. There is a significant gap in the literature regarding dyslipidemia in rural parts of Africa, where lipid profiles may not be captured through routine surveillance. This study aimed to characterize the prevalence and demo-graphic profile of dyslipidemia in T2D in the rural community of Ganadougou, Mali. We performed a cross-sectional study of 104 subjects with T2D in Ganadougou between November 2021 and March 2022. Demographic and lipid profiles were collected through cross-sectional surveys and serological analyses. The overall prevalence of dyslipidemia in T2D patients was 87.5% (91/104), which did not differ by sex (P = .368). High low-density lipoprotein cholesterol (LDL-C) was the most common lipid abnormality (78.9%, [82/104]). Dyslipidemia was associated with age and hypertension status (P = .013 and.036, respectively). High total and high LDL-C parameters were significantly associated with hypertension (P = .029 and .006, respectively). In low-resource settings such as rural Mali, there is a critical need to improve infrastructure for routine dyslipidemia screening to guide its prevention and intervention approaches. The high rates of dyslipidemia observed in Gandadougou, consistent with concomitant increases in cardiovascular diseases in Africa suggest that lipid profile assessments should be incorporated into routine medical care for T2D patients in African rural settings. 展开更多
关键词 CHOLESTEROL cross-sectional Study DYSLIPIDEMIA LIPIDS MALI Type 2 Diabetes
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Differential Cross Section of Electron Scattering From 3He and 3H Nuclei with Considering Pionic Contribution
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作者 Nazli Hamdolahi Farhad Zolfagharpour Negin Sattary Nikkhoo 《World Journal of Nuclear Science and Technology》 2012年第4期150-153,共4页
The excess pion inside the nucleus could change not only nucleons structure function, but also electron scattering cross section from nuclei. In this paper, we calculate pionic contribution in nuclear structure functi... The excess pion inside the nucleus could change not only nucleons structure function, but also electron scattering cross section from nuclei. In this paper, we calculate pionic contribution in nuclear structure functions of 3He and 3H nuclei and the differential cross sections of electron scattering from these nuclei. At first, we calculate the Fermi motion and binding energy contribution as an important nuclear medium effect in scattering cross sections and then we add pionic contribution to structure functions and differential cross sections of electron scattering from these nuclei that the Fermi motion and binding energy are considered. 展开更多
关键词 Pionic CONTRIBUTION Structure Function differential cross section
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A Study on Multivariable Interactions Concerning Radar Cross Section Reduction through Geometric Attributes
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作者 Evan Sharp 《Journal of Applied Mathematics and Physics》 2024年第7期2582-2593,共12页
This resolution 5 (25−1 factorial) study aimed to ascertain an understanding of the interactions between different geometries on the resulting Radar Cross Section (RCS) of a target. The results of the study are in lin... This resolution 5 (25−1 factorial) study aimed to ascertain an understanding of the interactions between different geometries on the resulting Radar Cross Section (RCS) of a target. The results of the study are in line with the general understanding of the impact different geometries have on RCS but show that geometries can also influence the variance of measured RCS, and typical attributes that reduce RCS increase the variance of the measured RCS. Notably, an increased angle between the front face of a plate and the direction of the radar signal decreased RCS but increased the variance of the RCS measured. 展开更多
关键词 Radar cross section RCS Geometrical Attributes RADAR STEALTH
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Patterns of Infertility and Abortion in Saudi Arabia: A Cross-Sectional Study
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作者 Majed Saeed Alshahrani 《Open Journal of Obstetrics and Gynecology》 2024年第6期911-922,共12页
Background: Infertility and abortion are significant reproductive health concerns globally, impacting individuals' well-being and healthcare systems. In Saudi Arabia, cultural, social, and religious factors influe... Background: Infertility and abortion are significant reproductive health concerns globally, impacting individuals' well-being and healthcare systems. In Saudi Arabia, cultural, social, and religious factors influence perceptions and management of these issues, necessitating research to understand the patterns and associated factors. Study Aim: This cross-sectional study aimed to investigate the patterns of infertility and abortion among 458 women in Saudi Arabia, focusing on demographic profiles, reproductive histories, medical conditions, and lifestyle factors. Methodology: Participants were recruited from healthcare facilities, and data on age, BMI, reproductive history, medical conditions, assisted reproduction methods, and lifestyle behaviors were collected. Statistical analyses, including chi-square tests, were conducted to examine associations between variables. Results: The majority of participants were aged 30 - 39 years (47.4%), with 76.9% experiencing secondary infertility. Among those with offspring (76.9%), 31% reported using assisted reproduction methods, primarily ovarian stimulators (54.2%). Abortion history was reported by 39.5% of participants. Significant associations were found between age and infertility type (X2 = 5.8, p = 0.054), having offspring and infertility type (X2 = 458.0, p = 0.001), menstrual irregularity and infertility type (X2 = 11.4, p = 0.001), and abortion history and delayed fertility (X2 = 10.4, p = 0.001). Conclusion: Our study reveals significant associations between demographic, medical, and lifestyle factors with infertility patterns and abortion history among Saudi women. These findings emphasize the need for tailored interventions addressing medical conditions, age-related factors, and access to reproductive healthcare services. 展开更多
关键词 INFERTILITY ABORTION Saudi Arabia Reproductive Health Assisted Reproduction cross-sectional Study
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Measurements of the Differential Elastic and Inelastic Scattering Cross Sections of ^(12)C
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作者 Zhang Kun Cao Jian-hua Dai Yun-shen Wan Dai-rong(Institute of Nuclear Science and Technology,Sichuan University,Chengdu 610064) 《Chinese journal of nuclear physics》 1995年第2期171-173,共3页
The differential elastic and inelastic scattering neutron cross sections of <sup>12</sup>C atE<sub>n</sub>=14.7 MeV produced by the T(d,n)<sup>4</sup>He reaction were measured usi... The differential elastic and inelastic scattering neutron cross sections of <sup>12</sup>C atE<sub>n</sub>=14.7 MeV produced by the T(d,n)<sup>4</sup>He reaction were measured using an associatedparticle fast neutron TOF spectrometer at 15 angles ranging from 15° to 130°.Theflight path was 2.54 m.The neutron detector consisting of an ST-451 liquid scintillatorwas massively shielded. 展开更多
关键词 ELASTIC scattering INELASTIC scattering differential cross section
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Partial wave scattering cross sections for He-HBr collision 被引量:7
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作者 余春日 凤尔银 +1 位作者 汪荣凯 杨向东 《Chinese Physics B》 SCIE EI CAS CSCD 2006年第11期2571-2577,共7页
A new anisotropic potential is fitted to ab initio data. The close-coupling approach is utilized to calculate state-tostate rotational excitation partial wave cross sections for elastic and inelastic collisions of He ... A new anisotropic potential is fitted to ab initio data. The close-coupling approach is utilized to calculate state-tostate rotational excitation partial wave cross sections for elastic and inelastic collisions of He atom with HBr molecule based on the fitted potential. The calculation is performed separately at the incident energies: 75, 100 and 200 meV.The tendency of the elastic and inelastic rotational excitation partial wave cross sections varying with total angular quantum number J is obtained. 展开更多
关键词 close-coupling approach partial wave cross sections He-BrH complex
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Recognition of the major scattering sources on complex targets based on the high frequency radar cross section integrated calculation technique 被引量:5
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作者 黄敏杰 吕明云 +1 位作者 黄俊 武哲 《Journal of Shanghai University(English Edition)》 CAS 2009年第4期316-321,共6页
Based on the high frequency (HF) integrated radar cross section (RCS) calculation approach, a technique of detecting major scattering source is developed by using an appropriate arithmetic for scattering distribut... Based on the high frequency (HF) integrated radar cross section (RCS) calculation approach, a technique of detecting major scattering source is developed by using an appropriate arithmetic for scattering distribution and scattering source detection. For the perfect adaptability to targets and the HF of the HF integrated RCS calculation platform, this technique is suitable to solve large complex targets and has lower requirement to the target modeling. A comparison with the result of 2-D radar imaging confirms the accuracy and reliability of this technique in recognition of the major scattering source on complex targets. This technique provides the foundation for rapid integrated evaluation of the scattering performance and 3-D scattering model reconstruction of large complex targets. 展开更多
关键词 stealth technique radar cross section (RCS) scattering center scattering distribution map 2-dimension radar imaging
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Analysis of Neutron Double-Differential Cross Sections for n + ^12 C Reaction Below 30 MeV 被引量:3
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作者 SUN Xiao-Jun DUAN Jun-Feng +1 位作者 WANG Ji-Min ZItANG Jing-Shang 《Communications in Theoretical Physics》 SCIE CAS CSCD 2007年第3X期534-540,共7页
Based on the light nucleus reaction model (Nucl. Sci. Eng. 133 (1999) 218), four aspects (neutron incident energy region, reaction channel analysis, the renewed level schemes and the optical model parameters) o... Based on the light nucleus reaction model (Nucl. Sci. Eng. 133 (1999) 218), four aspects (neutron incident energy region, reaction channel analysis, the renewed level schemes and the optical model parameters) of n+ ^12 C reaction are improved to calculate total outgoing neutron double-dilferential cross sections with modified LUNF code below 30 MeV. The calculated results agree fairly well with the experimental data at En = 14.1 MeV and 18 MeV. The analysis shows that the pre-equilibrium mechanism, which is exactly considered the conservation of energy, momentum and parity, dominates the whole reaction process. The contribution of the neutron emission from 5He to total energy- angular spectra is also considered properly. This modified LUNF code will be a useful tool to set up the file of neutron double-differential crass sections below 30 Me V in the neutron evaluation nuclear data library. 展开更多
关键词 double-differential cross section pre-equilibrium emission ^5He emission
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Bubble acoustical scattering cross section under multi-frequency acoustic excitation 被引量:1
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作者 时洁 杨德森 +3 位作者 张昊阳 时胜国 李松 胡博 《Chinese Physics B》 SCIE EI CAS CSCD 2017年第7期199-206,共8页
The acoustical scattering cross section is usually employed to evaluate the scattering ability of the bubbles when they are excited by the incident acoustic waves. This parameter is strongly related to many important ... The acoustical scattering cross section is usually employed to evaluate the scattering ability of the bubbles when they are excited by the incident acoustic waves. This parameter is strongly related to many important applications of performance prediction for search sonar or underwater telemetry, acoustical oceanography, acoustic cavitation, volcanology, and medical and industrial ultrasound. In the present paper, both the analytical and numerical analysis results of the acoustical scattering cross section of a single bubble under multi-frequency excitation are obtained. The nonlinear characteristics(e.g.,harmonics, subharmonics, and ultraharmonics) of the scattering cross section curve under multi-frequency excitation are investigated compared with single-frequency excitation. The influence of several paramount parameters(e.g., bubble equilibrium radius, acoustic pressure amplitude, and acoustic frequencies) in the multi-frequency system on the predictions of scattering cross section is discussed. It is shown that the combination resonances become significant in the multi-frequency system when the acoustic power is big enough, and the acoustical scattering cross section is promoted significantly within a much broader range of bubble sizes and acoustic frequencies due to the generation of more resonances. 展开更多
关键词 acoustical scattering cross section BUBBLES multi-frequency excitaion nonlinear characteristics
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Fully differential cross sections for C^(6+) single ionization of helium 被引量:1
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作者 李霞 马晓艳 +1 位作者 孙世艳 贾祥富 《Chinese Physics B》 SCIE EI CAS CSCD 2012年第11期184-189,共6页
The three-Coulomb-wave (3C) model is applied to study the single ionization of helium by 2 MeV/amu C6+ impact. Fully differential cross sections (FDCS) are calculated in the scattering plane and the results are c... The three-Coulomb-wave (3C) model is applied to study the single ionization of helium by 2 MeV/amu C6+ impact. Fully differential cross sections (FDCS) are calculated in the scattering plane and the results are compared with experimental data and other theoretical predictions. It is shown that the 3C results of the recoil peak are in very good agreement with experimental observations, and variation of the position of the binary peak with increasing momentum transfer also conforms better to the experimental results. Furthermore, the contributions of different scat- tering amplitudes are discussed. It turns out that the cross sections are strongly influenced by the interference of these amplitudes. 展开更多
关键词 ion atom impact ionization fully differential cross section three-Coulomb wave function
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Theoretical Analysis of Neutron Double-Differential Cross Section of n +^19F at 14.2 MeV 被引量:1
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作者 YAN Yu-Liang SUN Xiao-Jun +1 位作者 ZHANG Yue ZHANG Jing-Shang 《Communications in Theoretical Physics》 SCIE CAS CSCD 2007年第1期102-106,共5页
A new light nuclear reaction model has been developed and the double-differential measurements of lp shell nuclei have been analyzed successfully. Now, the application of this model is expanded to 19F of the 2s-ld she... A new light nuclear reaction model has been developed and the double-differential measurements of lp shell nuclei have been analyzed successfully. Now, the application of this model is expanded to 19F of the 2s-ld shell nucleus. The double-differential cross section of total outgoing neutron for n +^19F reactions at En=14.2 MeV has been calculated and analyzed, which agrees fairly well with the experimental measurements. In this paper, the contributions from different reaction channels to the double-differential cross sections have been analyzed in detail. The calculations indicate that this light nudear reaction model is also able to be used for the 2s-ld shell nucleus so long as the related level scheme couM be provided sufficiently. 展开更多
关键词 light nuclear reaction double-differential cross section pre-equillbrium emission discrete level
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