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Comparison of fish communities using environmental DNA metabarcoding and capture methods in a plateau Erhai Lake,China
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作者 Hong CHEN Wanchao HE +4 位作者 Fenge YANG Li LIAO Chengjie YIN Yushun CHEN Longgen GUO 《Journal of Oceanology and Limnology》 SCIE CAS CSCD 2024年第5期1597-1608,共12页
Environmental DNA(eDNA)has been used as an important tool for fish diversity analysis,which can greatly solve the problems in traditional survey methodology.However,little work has been done on the actual monitoring a... Environmental DNA(eDNA)has been used as an important tool for fish diversity analysis,which can greatly solve the problems in traditional survey methodology.However,little work has been done on the actual monitoring accuracy of eDNA.In this study,we analyzed the current status of fish resources in Erhai Lake in Yunnan,SW China,by dividing the lake into three sectors according to habitat differences,and compared the results of eDNA and traditional capture methods to investigate the shortcomings of the current analysis of eDNA results.A total of 27 fish species were detected by eDNA and traditional capture methods,including 20 and 19 fish species,respectively,and additional differences in fish composition between the two methods.The alpha diversity showed higher fish abundance and lower fish diversity by eDNA method compared to the traditional capture method,demonstrating that eDNA was not superior for use in fish diversity analysis.Fish community similarity analysis showed that community differences were generally significant for eDNA(P<0.05).RDA analysis indicated that environmental factors did not significantly affect fish communities monitored by the eDNA method.However,water temperature,aquatic plants,and water depth had significant(P<0.05)effects on fish communities in the traditional capture method,suggesting that eDNA results are insensitive to the effects of environmental factors.Our results illustrate the effectiveness of eDNA in fish identification and the issues in quantification compared to traditional capture methods.Therefore,combining eDNA with traditional methods is a more effective method for analyzing eDNA metabarcoding,following which the protocols of both quantitative methods can be designed to explore the regularity of eDNA quantification. 展开更多
关键词 environmental DNA traditional capture method fish communities habitat differences Erhai Lake
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Electron capture and excitation in intermediate-energy He^(2+)–H(1s,2s)collisions
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作者 刘亚东 贾聪聪 +5 位作者 马茗萱 高翔 刘玲 吴勇 陈向军 王建国 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第8期72-79,共8页
The semiclassical non-perturbative atomic orbital close-coupling approach has been employed to study the electron capture and excitation processes in He^(2+)-H(1s)and He^(2+)-H(2s)collision systems.In order to ensure ... The semiclassical non-perturbative atomic orbital close-coupling approach has been employed to study the electron capture and excitation processes in He^(2+)-H(1s)and He^(2+)-H(2s)collision systems.In order to ensure the accuracy of our calculated cross sections,a large number of high excited states and pseudostates are included in the expansion basis sets which are centered on the target and projectile,respectively.The total and partial charge transfer and excitation cross sections are obtained for a wide-energy domain ranging from 1 keV/amu to 200 keV/amu.The present calculations are also compared with the results from other theoretical methods.These cross section data are useful for the investigation of astrophysics and laboratory plasma. 展开更多
关键词 atomic orbital close-coupling(AOCC)method inelastic collision processes electron capture and excitation
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A Sub-element Adaptive Shock Capturing Approach for Discontinuous Galerkin Methods 被引量:2
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作者 Johannes Markert Gregor Gassner Stefanie Walch 《Communications on Applied Mathematics and Computation》 2023年第2期679-721,共43页
In this paper,a new strategy for a sub-element-based shock capturing for discontinuous Galerkin(DG)approximations is presented.The idea is to interpret a DG element as a col-lection of data and construct a hierarchy o... In this paper,a new strategy for a sub-element-based shock capturing for discontinuous Galerkin(DG)approximations is presented.The idea is to interpret a DG element as a col-lection of data and construct a hierarchy of low-to-high-order discretizations on this set of data,including a first-order finite volume scheme up to the full-order DG scheme.The dif-ferent DG discretizations are then blended according to sub-element troubled cell indicators,resulting in a final discretization that adaptively blends from low to high order within a single DG element.The goal is to retain as much high-order accuracy as possible,even in simula-tions with very strong shocks,as,e.g.,presented in the Sedov test.The framework retains the locality of the standard DG scheme and is hence well suited for a combination with adaptive mesh refinement and parallel computing.The numerical tests demonstrate the sub-element adaptive behavior of the new shock capturing approach and its high accuracy. 展开更多
关键词 High-order methods Discontinuous Galerkin spectral element method Finite volume method Shock capturing ASTROPHYSICS Stellar physics
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Capture-R法与微柱凝胶法在不规则抗体筛查中的应用 被引量:5
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作者 马春娅 于洋 +4 位作者 祁京 冯倩 关晓珍 骆群 汪德清 《临床输血与检验》 CAS 2010年第4期320-322,共3页
目的探讨Capture-R法与微柱凝胶法在不规则抗体筛查中的临床应用价值。方法采用微柱凝胶法与Capture-R法对600份临床患者标本做不规则抗体筛查平行试验,对抗体筛查阳性标本进行抗体鉴定。分析比较两种方法在不规则抗体筛查试验中的灵敏... 目的探讨Capture-R法与微柱凝胶法在不规则抗体筛查中的临床应用价值。方法采用微柱凝胶法与Capture-R法对600份临床患者标本做不规则抗体筛查平行试验,对抗体筛查阳性标本进行抗体鉴定。分析比较两种方法在不规则抗体筛查试验中的灵敏度和特异性。结果微柱凝胶法和Capture-R法阳性检出率分别为3.17%(19/600)和2.83%(17/600),两种方法灵敏度比较差异无统计学意义(P>0.05);特异性分别为89.47%(17/19)和100.00%(17/17),两种方法特异性比较差异无统计学意义(P>0.05)。结论 Capture-R法在不规则抗体筛查试验中的灵敏度和特异性均达到微柱凝胶法检测水平,可有效检出有临床意义的红细胞抗体,提高临床输血安全。 展开更多
关键词 微柱凝胶法 capture-R法 不规则抗体筛查 抗体鉴定
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Capture-R法应用于献血者不规则抗体筛查的可行性探讨 被引量:3
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作者 张慧贤 赵倩 +4 位作者 王艳彬 韩卫 陈志华 杨晓华 丁娜 《中国输血杂志》 CAS 2018年第6期661-663,共3页
目的探讨Capture-R法应用于献血者不规则抗体筛查的可行性。方法将17例含不规则抗体的标本随机放入本中心2015年12月的532例常规检测献血者标本中,分别用Capture-R法-混合细胞试剂和Capture-R法-3细胞试剂进行检测。结果 17例标本均为... 目的探讨Capture-R法应用于献血者不规则抗体筛查的可行性。方法将17例含不规则抗体的标本随机放入本中心2015年12月的532例常规检测献血者标本中,分别用Capture-R法-混合细胞试剂和Capture-R法-3细胞试剂进行检测。结果 17例标本均为阳性反应,而532例献血者标本经Capture-R法-混合细胞检测有5例标本呈阳性反应,其中1例经鉴定含抗-D,4例不含不规则抗体;经Capture-R法-3细胞检测有2例标本呈阳性反应,其中1例为Capture-R法-混合细胞检出含抗-D的同一标本,1例不含不规则抗体。结论 Capture-R法能有效检出不规则抗体且Capture-R法-混合细胞试剂更适用于献血者的大规模筛查。 展开更多
关键词 献血者 不规则抗体 全自动血型仪 capture-R法
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Capture-R法在交叉配血实验中的应用研究
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作者 冯倩 张晓娟 +4 位作者 马春娅 关小珍 付丽辉 于洋 汪德清 《科学技术与工程》 2010年第33期8218-8220,共3页
探讨Capture-R法在交叉配血实验中的应用。采用Capture-R技术对609例标本进行交叉配血实验,并与微柱凝胶法进行比对实验。对实验中不一致的标本用经典抗人球蛋白实验确认。609例标本中Capture-R法和微柱凝胶法交叉配血阳性检出率分别为4... 探讨Capture-R法在交叉配血实验中的应用。采用Capture-R技术对609例标本进行交叉配血实验,并与微柱凝胶法进行比对实验。对实验中不一致的标本用经典抗人球蛋白实验确认。609例标本中Capture-R法和微柱凝胶法交叉配血阳性检出率分别为4.43%(27/609)和3.28%(20/609),两种方法灵敏度比较,没有显著性差异(P>0.05);特异性分别为77.78%(21/27)和100.00%(20/20),两种方法特异性比较无显著性差异(P>0.05)。Capture-R法在交叉配血试验中的灵敏度和特异性均达到了微柱凝胶法水平,是一种安全、灵敏、可靠的交叉配血技术,而且处理样本具有高通量的特点,可应用于临床输血相容性检测。 展开更多
关键词 交叉配血实验 capture-R法 微柱凝胶法 抗人球蛋白实验
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<i>In Vitro</i>Evaluation System of Pharmacokinetics and Irradiation Effect in Boron Neutron Capture Therapy (BNCT) Using Three-Dimensional Artificial Human Tumor Tissue Model 被引量:1
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作者 Shintaro Ishiyama Yoshiya Asano +2 位作者 Minoru Suzuki Mitsuru Akashi Hiroshi Shimoda 《Journal of Cancer Therapy》 2019年第10期835-845,共11页
Boron neutron capture therapy (BNCT) is based on the incorporation of boron-containing drugs to cancer cells and the nuclear reaction of 10B atoms by thermal neutron irradiation results in tumor degeneration. For the ... Boron neutron capture therapy (BNCT) is based on the incorporation of boron-containing drugs to cancer cells and the nuclear reaction of 10B atoms by thermal neutron irradiation results in tumor degeneration. For the development of this therapy, currently, long time and high cost consuming experiments using many animals are required. In this study, we constructed a new in vitro evaluation system for BNCT by combination of an artificial tumor tissue model, comprised of normal human dermal-derived fibroblast (NHDF) and human pancreatic cancer cell line BxPC3, and the optical plastic material CR-39 as a solid state nuclear track detector. Administration of boronophenylalanine (10BPA) as a boron-containing drug and neutron irradiation up to 2.52 × 1012 n/cm2 to the control tissue constructed by NHDF (NHDF3D) and BxPC3 cell loaded tissue (NHDF3D/BxPC3) resulted in detection of 1.6 times higher number of α-ray/recoiled Li particle tracks in NHDF3D/BxPC3 in comparison to NHDF3D, demonstrating that putative irradiation damage to cancer cells can be evaluated by this system. On a cellular level, the hit number of α-ray/recoiled Li particle tracks per single BxPC3 cells and NHDF was evaluated as 5.46 and 1.71, respectively. The tumor and normal tissue ratio (T/N ratio) was 3.19, which was corresponded with those of BPA as 2 - 4 that reported in the previous studies. This new in vitro evaluation system may provide a useful tool for a low cost, labor-saving, and non-animal method for the development of new boron-containing drugs or improvement of BNCT conditions. 展开更多
关键词 Boron Neutron capture Therapy (BNCT) Boronophenylalanine (10BPA) Artificial Human Tumor TISSUE MODEL Cell Accumulation method
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Study on the Effect of Preparation Parameters of K<sub>2</sub>CO<sub>3</sub>/Al<sub>2</sub>O<sub>3</sub>Sorbent on CO<sub>2</sub>Capture Capacity at Flue Gas Operating Conditions 被引量:1
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作者 Javad Esmaili Mohammad Reza Ehsani 《Journal of Encapsulation and Adsorption Sciences》 2013年第2期57-63,共7页
In this paper, study on the effect of preparation conditions of K2CO3/Al2O3 sorbent was done. Box-Behnken design was applied to study the influence of four parameters involve initial solution concentration, impregnati... In this paper, study on the effect of preparation conditions of K2CO3/Al2O3 sorbent was done. Box-Behnken design was applied to study the influence of four parameters involve initial solution concentration, impregnation time and calcination step temperature and time. A quadratic model was used to correlate the sorbent capture capacity. The model was used to calculate the optimum conditions for preparing sorbent. From the analysis of variance (ANOVA), the most influential factor on each experimental design response was identified. The potassium-based sorbents used in this study were prepared by impregnating K2CO3 on Al2O3 support. The CO2 capture capacity was measured in the presence of H2O in a fixed-bed reactor at CO2 capture temperature of 60°C using breakthrough curves. The optimum sorbent prepared by this method showed CO2 capture capacity of 77.21 mg CO2/g sorbent. It was observed that the experimental values obtained were in good agreement with the values predicted by the model, with relatively small errors between the predicted and the actual values. The results obtained in this study can be used as basic data for study on design and operating condition optimization of CO2 capture process using these sorbents. 展开更多
关键词 CO2 capture K2CO3/Al2O3 SORBENT Response Surface method Box-Behnken Design
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Measurement of Neutron Capture Cross Section for ^(180)Hf 被引量:3
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作者 Chen Jinxiang Shi Zhaomin Tang Guoyou Zhang Guohui Institute of Heavy Ion Physics,Peking University,Beijing 100871Lu Hanlin Han Xiaogang Huang Xiaolong China Institute of Atomic Energy,P.O.Box 275(3),Beijing 102413 《Chinese journal of nuclear physics》 1997年第2期110-114,共5页
The neutron capture cross section for <sup>180</sup>Hf relative to the <sup>197</sup>Au(n,γ)<sup>198</sup>Au reaction ismeasured at neutron energies of 0.52,1.10 and 1.60 MeV usi... The neutron capture cross section for <sup>180</sup>Hf relative to the <sup>197</sup>Au(n,γ)<sup>198</sup>Au reaction ismeasured at neutron energies of 0.52,1.10 and 1.60 MeV using the activation method.Theactivities of the products are measured with a high resolution HPGe detector gamma ray spec-trometer.The errors of the measured results are 5%~6%.Our results have a good agreementwith those of other authors within errors.Cross sections for the reaction are calculated withUNF code and recommended data are also given. 展开更多
关键词 100Hf 198Au NEUTRON capture CROSS SECTION Activition method
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Measurement of fast-neutron capture cross sections for ^(75)As 被引量:1
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作者 ZHANGGuo-Hui LUHan-Lin 《Nuclear Science and Techniques》 SCIE CAS CSCD 2001年第3期161-164,共4页
The cross sections of the75 As(n,γ)76As reaction were measured in the neutron energy range from 0.50 to 1.50 MeV by using the activation technique. Neutrons were produced via the T(p,n)3He reaction and the cross sect... The cross sections of the75 As(n,γ)76As reaction were measured in the neutron energy range from 0.50 to 1.50 MeV by using the activation technique. Neutrons were produced via the T(p,n)3He reaction and the cross sections of the 197Au(n,γ)198Au reaction were used to determine the absolute neutron flux. Present results are compared with existing measurements and evaluations. 展开更多
关键词 中子俘获 实验截面 ^75As
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Gradient-augmented hybrid interface capturing method for incompressible two-phase flow
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作者 付峥 吴士玉 刘凯欣 《Chinese Physics B》 SCIE EI CAS CSCD 2016年第6期283-289,共7页
Motivated by inconveniences of present hybrid methods,a gradient-augmented hybrid interface capturing method(GAHM) is presented for incompressible two-phase flow.A front tracking method(FTM) is used as the skeleto... Motivated by inconveniences of present hybrid methods,a gradient-augmented hybrid interface capturing method(GAHM) is presented for incompressible two-phase flow.A front tracking method(FTM) is used as the skeleton of the GAHM for low mass loss and resources.Smooth eulerian level set values are calculated from the FTM interface,and are used for a local interface reconstruction.The reconstruction avoids marker particle redistribution and enables an automatic treatment of interfacial topology change.The cubic Hermit interpolation is employed in all steps of the GAHM to capture subgrid structures within a single spacial cell.The performance of the GAHM is carefully evaluated in a benchmark test.Results show significant improvements of mass loss,clear subgrid structures,highly accurate derivatives(normals and curvatures) and low cost.The GAHM is further coupled with an incompressible multiphase flow solver,Super CE/SE,for more complex and practical applications.The updated solver is evaluated through comparison with an early droplet research. 展开更多
关键词 interface capturing hybrid method mass loss incompressible two-phase flow
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Single electron capture in collisions of N^(q+)(q=5,6,7)ions with helium
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作者 王菲 王苗苗 《Chinese Physics B》 SCIE EI CAS CSCD 2011年第11期201-205,共5页
Close-coupling calculations are carried out for cross sections of the single electron capture in collisions of N^q+(q = 5, 6, 7) ions with helium atoms in the collision velocity range from 0.3 a.u. to 1.8 a.u. The ... Close-coupling calculations are carried out for cross sections of the single electron capture in collisions of N^q+(q = 5, 6, 7) ions with helium atoms in the collision velocity range from 0.3 a.u. to 1.8 a.u. The relative importances of the single ionization (SI) to the single capture (SC) are investigated for the N^q+ (q= 5, 6, 7) projectiles, respectively. The SI/SC cross section ratio for the N7+ projectile obtained from our calculations is in excellent agreement with the experimental data. The ratio curves also show us distinct behaviours when the charge of the projectile is different. The partial electron capture cross sections for different projectiles indicate that the electron on the target He atom tends to be captured by the projectile into its lower orbital of the outer shell with the decreasing projectile charge. 展开更多
关键词 close-coupling method electron capture cross section
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Ionization and single electron capture in collision of highly charged Ar^(16+) ions with helium
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作者 王菲 芶秉聪 《Chinese Physics B》 SCIE EI CAS CSCD 2008年第4期1227-1230,共4页
This paper uses the two-centre atomic orbital close-coupling method to study the ionization and the single electron capture in collision of highly charged Ar^16+ ions with He atoms in the velocity range of 1.2-1.9 a.... This paper uses the two-centre atomic orbital close-coupling method to study the ionization and the single electron capture in collision of highly charged Ar^16+ ions with He atoms in the velocity range of 1.2-1.9 a.u.. The relative importance of single ionization (SI) to single capture (SC) is explored. The comparison between the calculation and experimental data shows that the SI/SC cross section ratios from this work are in good agreement with experimental data. The total single electron ionization cross sections and the total single electron capture cross sections are also given for this collision. The investigation of the partial electron capture cross section shows a general tendency of capture to larger n and l with increasing velocity from 1.2 to 1.9 a.u.. 展开更多
关键词 close-coupling method electron capture highly charged ions
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Measurements of fast-neutron capture cross sections for ^(159)Tb and ^(169)Tm 被引量:1
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作者 ChenJin-Xiang ShiZhao-Min 《Nuclear Science and Techniques》 SCIE CAS CSCD 1998年第3期138-142,共5页
1IntroductionFastneutroncapturecrossectionsareimportantfortheunderstandingofnuclearreactionmechanismsandforv... 1IntroductionFastneutroncapturecrossectionsareimportantfortheunderstandingofnuclearreactionmechanismsandforvariousapplicati... 展开更多
关键词 核反应 中子俘获 ^159Tb ^169Tm 截面
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Analysis of the elemental spectral characteristics of single elemental capture spectrum log using Monte-Carlo simulation
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作者 Lan Chang-Lin Zhan Xu-Wen +4 位作者 Wu Hong-Liang Zhang Yi Liu Tong Feng Zhou Lv Tao 《Applied Geophysics》 SCIE CSCD 2019年第3期321-326,396,共7页
In this study,the gamma-ray spectrum of single elemental capture spectrum log was simulated.By numerical simulation we obtain a single-element neutron capture gamma spectrum.The neutron and photon transportable proces... In this study,the gamma-ray spectrum of single elemental capture spectrum log was simulated.By numerical simulation we obtain a single-element neutron capture gamma spectrum.The neutron and photon transportable processes were simulated using the Monte Carlo N-Particle Transport Code System(MCNP),where an Am–Be neutron source generated the neutrons and thermal neutron capture reactions with the stratigraphic elements.The characteristic gamma rays and the standard gamma spectra were recorded,from analyzing of the characteristic spectra analysis we obtain the ten elements in the stratum,such as Si,Ca,Fe,S,Ti,Al,K,Na,Cl,and Ba.Comparing with single elemental capture gamma spectrum of Schlumberger,the simulated characteristic peak and the spectral change results are in good agreement with Schlumberger.The characteristic peak positions observed also consistent with the data obtained from the National Nuclear Data Center of the International Atomic Energy Agency.The neutron gamma spectrum results calculated using this simple method have practical applications.They also serve as an reference for data processing using other types of element logging tools. 展开更多
关键词 Neutron gamma spectrum single element elemental capture spectrum logging ECS thermal neutron capture Monte Carlo method MCNP
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Radiation Sensitivity of <i>in Vitro</i>Evaluation System of Pharmacokinetics in Boron Neutron Capture Therapy (BNCT) Using Three-Dimensional Artificial Human Tumor Tissue Model
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作者 Shintaro Ishiyama Minoru Suzuki 《Journal of Cancer Therapy》 2019年第12期1025-1035,共11页
One of the important matters that must be determined in advance when performing BNCT treatment is the optimization of neutron irradiation time and dose. In this article, following the previous article (2.52 × 101... One of the important matters that must be determined in advance when performing BNCT treatment is the optimization of neutron irradiation time and dose. In this article, following the previous article (2.52 × 1012 n/cm2) (Case 1), double irradiation (5.04 × 1012 n/cm2) was further performed (Case 2) by verifying the radiation sensitivity performance of the artificial tumor tissue NHDF3D/BxPC3 and the possibility of evaluating the optimum neutron dose required for treatment was examined. As a result, although the radiation damage rate in the normal tissue NHDF3D and the tumor tissue BxPC3 increased in proportion to the irradiation dose due to heavy irradiation in Case 1 or more, the increase in the damage rate in the normal tissue exceeded the tumor tissue. Furthermore, the tumor/normal tissue damage ratio T/N ratio showed the maximum value in Case 1, and the dose ratio in Case 2 with a higher dose showed a tendency to decrease. From the above experimental facts, it was shown that irradiation dose optimization is possible to some extent by an evaluation method using an artificial tumor tissue. 展开更多
关键词 Boron Neutron capture Therapy (BNCT) Boronophenylalanine (10BPA) Artificial Human Tumor TISSUE MODEL Cell Accumulation method
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Measurement of Neutron Capture Cross Section for ^(152)Sm
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作者 Luo Xiao-bing Xia Yi-jun Yang Zhi-hua Liu Man-tian (Institute of Nuclear Science and Technology,Sichuan University.Chengdu 610064) 《Chinese journal of nuclear physics》 1994年第3期275-277,共3页
The cross sections for <sup>152</sup>Sm(n,γ)<sup>153</sup>Sm relative to <sup>197</sup>Au neutron capture crosssection are measured by activation method in neutron energy range o... The cross sections for <sup>152</sup>Sm(n,γ)<sup>153</sup>Sm relative to <sup>197</sup>Au neutron capture crosssection are measured by activation method in neutron energy range of 22-1019 keV.The results are compared with the previous work. 展开更多
关键词 ACTIVATION method 152Sm(n γ)153Sm NEUTRON capture cross SECTION
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Construction of Conservative Numerical Fluxes for the Entropy Split Method
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作者 Björn Sjögreen H.C.Yee 《Communications on Applied Mathematics and Computation》 2023年第2期653-678,共26页
The entropy split method is based on the physical entropies of the thermally perfect gas Euler equations.The Euler flux derivatives are approximated as a sum of a conservative portion and a non-conservative portion in... The entropy split method is based on the physical entropies of the thermally perfect gas Euler equations.The Euler flux derivatives are approximated as a sum of a conservative portion and a non-conservative portion in conjunction with summation-by-parts(SBP)difference boundary closure of(Gerritsen and Olsson in J Comput Phys 129:245-262,1996;Olsson and Oliger in RIACS Tech Rep 94.01,1994;Yee et al.in J Comp Phys 162:33-81,2000).Sj?green and Yee(J Sci Comput)recently proved that the entropy split method is entropy conservative and stable.Stand-ard high-order spatial central differencing as well as high order central spatial dispersion relation preserving(DRP)spatial differencing is part of the entropy stable split methodol-ogy framework.The current work is our first attempt to derive a high order conservative numerical flux for the non-conservative portion of the entropy splitting of the Euler flux derivatives.Due to the construction,this conservative numerical flux requires higher oper-ations count and is less stable than the original semi-conservative split method.However,the Tadmor entropy conservative(EC)method(Tadmor in Acta Numerica 12:451-512,2003)of the same order requires more operations count than the new construction.Since the entropy split method is a semi-conservative skew-symmetric splitting of the Euler flux derivative,a modified nonlinear filter approach of(Yee et al.in J Comput Phys 150:199-238,1999,J Comp Phys 162:3381,2000;Yee and Sj?green in J Comput Phys 225:910934,2007,High Order Filter Methods for Wide Range of Compressible flow Speeds.Proceedings of the ICOSAHOM09,June 22-26,Trondheim,Norway,2009)is proposed in conjunction with the entropy split method as the base method for problems containing shock waves.Long-time integration of 2D and 3D test cases is included to show the com-parison of these new approaches. 展开更多
关键词 Finite-difference method Entropy conservation Entropy splitting Shock capturing
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医院中子照射器治疗束中子参数测量
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作者 石斌 张书峰 +9 位作者 陈军 刘显科 肖鸿飞 张紫竹 屈渤添 王倩 曹平 张庆贤 宋明哲 刘蕴韬 《同位素》 CAS 2024年第1期1-6,共6页
为了对医院中子照射器的设计指标进行验证,利用金箔活化法测量了其治疗束出口处中子注量率,并采用金刚石探测单元的扫描装置测量治疗束出口处热中子、超热中子、快中子和γ射线注量率的径向分布。结果显示,在30 kW满功率运行时,热中子... 为了对医院中子照射器的设计指标进行验证,利用金箔活化法测量了其治疗束出口处中子注量率,并采用金刚石探测单元的扫描装置测量治疗束出口处热中子、超热中子、快中子和γ射线注量率的径向分布。结果显示,在30 kW满功率运行时,热中子束及超热中子束出口中心处,热中子注量率分别为1.75×10^(9)cm^(-2)·s^(-1)和6.57×10^(7)cm^(-2)·s^(-1),超热中子注量率分别为1.41×10^(7)cm^(-2)·s^(-1)和3.14×10^(8)cm^(-2)·s^(-1);治疗束主要分布在束流孔径内,靠近束流边缘会出现指数级下降现象。该测量结果为医院中子照射器开展后续相关测试及实验提供了参数支持。 展开更多
关键词 热中子注量率 硼中子俘获治疗 活化法 径向分布
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二氧化碳捕集耦合工艺设计与优化
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作者 马国光 王金阳 张涛 《低碳化学与化工》 CAS 北大核心 2024年第7期76-83,共8页
采用醇胺法工艺对高含碳天然气进行脱碳处理时,其能耗随着碳含量的增加而提高。为降低高含碳天然气的脱碳能耗,提出了一种醇胺法工艺(N-甲基二乙醇胺作吸收剂)与级间冷却、富液分流解吸、酸气再压缩热泵和蒸汽机械再压缩技术(MVR)热泵... 采用醇胺法工艺对高含碳天然气进行脱碳处理时,其能耗随着碳含量的增加而提高。为降低高含碳天然气的脱碳能耗,提出了一种醇胺法工艺(N-甲基二乙醇胺作吸收剂)与级间冷却、富液分流解吸、酸气再压缩热泵和蒸汽机械再压缩技术(MVR)热泵工艺耦合的二氧化碳(CO_(2))捕集耦合工艺流程(简称“耦合工艺”)。采用AspenHysys软件对影响耦合工艺节能效果的关键参数(级间物流冷却温度、贫液节流后压力、酸气再压缩压力和再生塔底重沸器温度)进行了分析,并通过响应面分析与遗传算法结合的方式对关键参数进行了优化。结果表明,优化后耦合工艺的级间物流冷却温度为58℃,贫液节流后压力为0.084MPa,酸气再压缩压力为0.195MPa,再生塔底重沸器温度为92℃。与联合工艺(膜分离+醇胺法)相比,耦合工艺的能耗明显降低,脱碳单位能耗(脱除1 t CO_(2)需要消耗的能量)由1.338 GJ/t下降至1.110 GJ/t。与优化前相比,耦合工艺优化后的净化气中CO_(2)含量(体积分数)由2.533%下降至2.326%,脱碳单位能耗由1.110GJ/t下降至1.074GJ/t。 展开更多
关键词 CO_(2)捕集 耦合工艺 参数优化 响应面法 遗传算法
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