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Performance optimization of the neutron-sensitive image intensifier used in neutron imaging

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Chinese Physics B 2024年第8期33卷 380-387页

作者：谭金昊宋玉收周健荣杨文钦蒋兴奋刘杰张超月周晓娟夏远光刘术林闫保军刘辉王松林赵豫斌庄建孙志嘉陈元柏 Harbin Engineering University Harbin 150000China Spallation neutron Source Science Center Dongguan 523803China State Key Laboratory of Particle Detection and Electronics Institute of High Energy PhysicsChinese Academy of SciencesBeijing 100049China Key Laboratory of China Building Materials Industry for Special Photoelectric Materials Institute of Special Glass Fiber and Optoelectronic Functional MaterialsChina Building Materials AcademyBeijing 100024China

As a non-destructive testing technology,neutron imaging plays an important role in various fields,including material science,nuclear engineering,and fundamental *** imaging detector with a neutron-sensitive image intensifier has been developed and demonstrated to achieve good spatial resolution and timing ***,the influence of the working voltage on the performance of the neutron-sensitive imaging intensifier has not been *** optimize the performance of the neutron-sensitive image intensifier at different voltages,experiments have been performed at the China Spallation neutron Source(CSNS)neutron *** change in the light yield and imaging quality with different voltages has been *** is shown that the image quality benefits from the high gain of the microchannel plate(MCP)and the high accelerating electric field between the MCP and the *** the accelerating electric field is more effective than increasing the gain of MCPs for the improvement of the imaging *** the total gain of the MCP stack can be realized more effectively by improving the gain of the standard MCP than that of the n *** results offer a development direction for image intensifiers in the future.

关键词： neutron detector neutron imaging microchannel plate image intensifier

Spontaneous Imbibition of Water and Determination of Effective Contact Angles in the Eagle Ford Shale Formation Using neutron imaging

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Journal of Earth Science 2017年第5期28卷 874-887页

作者： Victoria H.DiStefano Michael C.Cheshire Joanna McFarlane Lindsay M.Kolbus Richard E.Hale Edmund Perfect Hassina Z.Bilheux Louis J.Santodonato Daniel S.Hussey David L.Jacobson Jacob M.LaManna Philip R.Bingham Vitaliy Starchenko Lawrence M.Anovitz Physical Sciences Directorate Chemical Sciences Division Oak Ridge National Laboratory Bredesen Center University of Tennessee Energy & Environmental Sciences Directorate Energy & Transportation Sciences Division Oak Ridge National Laboratory neutron Sciences Directorate Chemical and Engineering Materials Division Oak Ridge National Laboratory Nuclear Science & Engineering Directorate Reactor & Nuclear Systems Division Oak Ridge National Laboratory Department of Earth and Planetary Science University of Tennessee neutron Sciences Directorate Instrument and Source Division Oak Ridge National Laboratory Physical Measurement Laboratory National Institute of Standards and Technology Energy & Environmental Sciences Directorate Electrical & Electronics Systems Research DivisionOak Ridge National Laboratory

Understanding of fundamental processes and prediction of optimal parameters during the horizontal drilling and hydraulic fracturing process results in economically effective improvement of oil and natural gas extraction. Although modern analytical and computational models can capture fracture growth, there is a lack of experimental data on spontaneous imbibition and wettability in oil and gas reservoirs for the validation of further model development. In this work, we used neutron im- aging to measure the spontaneous imbibition of water into fractures of Eagle Ford shale with known geometries and fracture orientations. An analytical solution for a set of nonlinear second-order diffe- rential equations was applied to the measured imbibition data to determine effective contact angles. The analytical solution fit the measured imbibition data reasonably well and determined effective con- tact angles that were slightly higher than static contact angles due to effects of in-situ changes in veloci- ty, surface roughness, and heterogeneity of mineral surfaces on the fracture surface. Additionally, small fracture widths may have retarded imbibition and affected model fits, which suggests that aver- age fracture widths are not satisfactory for modeling imbibition in natural systems.

关键词： spontaneous imbibition effective contact angle neutron imaging Eagle Ford shale rock fractures.

Optimal design of coded aperture used for Z-Pinch driven fusion neutron imaging

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Science China(Technological Sciences) 2015年第7期58卷 1289-1293页

作者： JIA QingGang HU HuaSi ZHENG XiangYang ZHANG FengNa WANG DongMing HU Guang ZHANG TianKui WU YueLei Institute of Nuclear Science and Technology Xi'an Jiaotong University State Environmental Protection Administration (SEPA) Nuclear and Radiation Safety Centre Research Center of Laser Fusion China Academy of Engineering Physics

Currently,the neutron yield of Z-Pinch is lower than that of laser driven *** the neutron imaging for this facility,the signal to noise ratio(SNR)has a significant influence on the expected spatial resolution of the reconstructed fusion core,especially in the condition of low neutron *** this paper,mathematical model is purposed to describe the dependence of aperture parameters on the imaging *** investigation shows that the imaging SNR is closely related to the size of contrast boundary on the point spread *** to this,a novel non-uniform redundancy penumbra apertures array is *** addition,the imaging performances of this novel coded aperture,penumbra aperture and ring aperture are evaluated and compared by Monte Carlo *** comparison shows that this novel aperture has significant advantage compared to the penumbra aperture which is commonly used for neutron imaging with low *** encouraging results can provide reference for the optimal design of the coded aperture used in the neutron imaging for Z-pinch driven fusion with low neutron yield.

关键词： Z-pinch driven fusion neutron imaging coded aperture signal to noise ratio low neutron yield

neutron imaging at Peking University

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Engineering Sciences 2009年第4期7卷 83-85页

作者： Zou Yubin Guo Zhiyu Tang Guoyou Mo Dawei State Key Laboratory of Nuclear Physics and Technology ＆ School of Physics Peking University Beijing 100871 China

neutron imaging techniques were investigated at Peking University based on a 4.5 MV Van de Graaff *** thermal neutron radiography,fast neutron radiography and fast neutron resonance radiography were *** low neutron flux limits the image quality.A new radio frequency quadrupole (RFQ) accelerator based on neutron source with a yield of 1 012 n/s is being set up.

关键词： neutron imaging thermal neutron radiography fast neutron radiography fast neutron resonance radiography

New Opportunities for neutrons in Environmental and Biological Sciences

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Frontiers of Environmental Science & Engineering 2024年第7期18卷 179-186页

作者： Alexander Johs Shuo Qian Leighton Coates Brian H.Davison James G.Elkins Xin Gu Jennifer Morrell-Falvey Hugh O'Neill Jeffrey M.Warren Eric M.Pierce Kenneth Herwig Oak Ridge National Laboratory Oak RidgeTN37831USA

The use of neutron methods in environmental and biological sciences is rapidly emerging and accelerating with the development of new instruments at neutron user *** article,based on a workshop held at Oak Ridge National Laboratory(ORNL),offers insights into the application of neutron techniques in environmental and biological *** highlight recent advances and identify key challenges and potential future research *** include soil and rhizosphere processes,root water dynamics,plant-microbe interactions,structure and dynamics of biological systems,applications in synthetic biology and enzyme engineering,next-generation bioproducts,biomaterials and bioenergy,nanoscale structure,and fluid dynamics of porous materials in *** provide an outlook on emerging opportunities with an emphasis on new capabilities that will be enabled at the Spallation neutron Source Second Target Station currently under design at *** mission of scientific neutron user facilities worldwide is to enable science using state-of-the-art neutron *** aim to encourage researchers in the environmental and biological research community to explore the unique capability afforded by neutrons at these facilities.

关键词： neutrons Environment Biology neutron imaging neutron scattering Second Target Station(STS)

Development and Application of neutron Computed Tomography at CARR

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Development and Application of Neutron Computed Tomography a...