Preparation and Accurate Quantification of 238U Coatings on Thin-Backed

Preparation and Accurate Quantification of 238U Coatings on Thin-Backed | Research Square window.SnipcartSettings = { analytics: { enabled: false } }; (function() { var accessVector = localStorage.getItem('access_vector') || ''; window.dataLayer = window.dataLayer || []; if (accessVector) { window.dataLayer.push({ user: { profile: { profileInfo: { snid: accessVector } } } }); } })(); (function(w,d,s,l,i){w[l]=w[l]||[];w[l].push({'gtm.start':new Date().getTime(),event:'gtm.js'});var f=d.getElementsByTagName(s)[0],j=d.createElement(s),dl=l!='dataLayer'?'&l='+l:'';j.async=true;j.src='https://www.googletagmanager.com/gtm.js?id='+i+dl;f.parentNode.insertBefore(j,f);})(window,document,'script','dataLayer','GTM-K279D39R'); Browse Preprints In Review Journals COVID-19 Preprints AJE Video Bytes Research Tools Research Promotion AJE Professional Editing AJE Rubriq About Preprint Platform In Review Editorial Policies Our Team Advisory Board Help Center Sign In Submit a Preprint Cite Share Download PDF Research Article Preparation and Accurate Quantification of 238 U Coatings on Thin-Backed He Yuyang, Liu Yina, Liu Yuntao, Chen Kesheng, Li Chunjuan, Bao Jie, and 1 more This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-7926956/v1 This work is licensed under a CC BY 4.0 License Status: Posted Version 1 posted You are reading this latest preprint version Abstract For neutron detectors used in high-flux neutron beams, dense and uniform 238 U coatings are prepared by electrodeposition using natural uranium on 2µm-thick aluminized mylar foils. The mylar foils with a thickness of µm have a certain degree of ductility and a low neutron reaction cross-section, which can effectively reduce interference signals. Accurate Quantification of 238 U coatings is conducted using a specially designed small solid angle device and a grid ionization chamber, respectively. The results show that the weights of 238 U in coatings are 0.335mg and 0.310mg, with relative uncertainty of 1.02%-1.09% and consistent within the uncertainties. Quantification Uranium in coatings Small solid angle device Grid ionization chamber Alpha spectrometry Figures Figure 1 Figure 2 Figure 3 Figure 4 Figure 5 Figure 6 Figure 7 Figure 8 Figure 9 1. Introduction Uranium isotopes play a crucial role in neutron physics[1]. Fission ionization chambers based on nuclear fission reactions such as 235 U(n,f) and 238 U(n,f) are widely applied in neutron detection. They exhibit excellent n-γ discrimination capability, are free from radiation damage issues, and feature flexible and diverse structures[2,3]. The uranium coating is one of the important components for the fission ionization chamber. The measurement results such as neutron-induced fission cross section and neutron flux are directly related to the number of target nuclei in the fission coating[4,5]. Therefore, it is necessary to conduct an accurate quantitative analysis of the uranium coating. Uranium isotopes can generate alpha particles through spontaneous decay. Thus, the alpha spectrometry method[6] is widely used for the quantitative analysis of uranium in the coating, which is to obtain the uranium content in the coating by measuring the count rate of alpha particles. With the significant improvement in the performance and neutron flux of the new generation of neutron science devices, neutron detectors are required to exhibit excellent performance under high-flux neutron beams[7]. To avoid strong interference signals caused by the interaction of neutrons or secondary particles with other substances outside the target nucleus, the amount of material in the beam should be minimized. In this paper, 238 U coating is prepared on a 2µm-thick aluminized mylar foils by electrodeposition. This foil has good ductility and a low neutron reaction cross-section. Quantitative measurements of the 238 U are conducted using two devices based on alpha spectrometry method, which are called the small solid angle device (SSA) and the grid ionization chamber (GIC). And uncertainty analysis is performed. The results of two devices are consistent within the uncertainties. 2. Preparation of U coating on thin-backing For neutron detectors used in high-flux neutron beams, a cathode for the ionization chamber is prepared using a µm-thick aluminized mylar foil as the backing. This material has certain ductility and a low neutron reaction cross-section, which can effectively reduce interference signals and achieve neutron detection in the beam line. Figure 1 shows the backing made by bonding a PCB ring and a 2µm-thick mylar film using specialized tooling. The ductility of the mylar film results in a smooth mirror-like effect on the backing. To preparing 238 U coating on thin-backing by electrodeposition[8,9], a experimental equipment has been designed in Fig. 2 . The aluminized mylar foil serves as the cathode, and the platinum wire with a diameter of 1mm is used as the anode. By bending the platinum wire into a concentric circular with a maximum diameter of 40mm, a dense and highly uniform metal coating can be obtained. The distance between adjacent concentric rings is 2mm, which can effectively prevent the gas generated by the cathodic hydrogen evolution reaction from damaging the substrate and affecting the uniformity of the coating. In the experiment, natural uranium is dissolved in concentrated nitric acid, dried to form uranyl nitrate (UO 2 (NO 3 ) 2 ·6H 2 O), and then dissolve in dilute nitric acid solution to prepare uranium feed solution for later use. An isopropanol solution is used as the electroplating solution to dissolve the uranium solution as the electrolyte, and the initial pH value of the electrolyte is adjusted with nitric acid solution. The obtained 238 U coatings are shown in Fig. 3 , with the active area diameter of the coatings being 30mm. 3. Quantification of U in coatings The α particles emitted during the decay of the uranium nucleus are isotropic. Therefore, as long as the number of α particles emitted by the uranium coating in a certain direction and solid angle is measured, the total number of α particles emitted by the uranium within the coating can be obtained. Thereby, the mass of uranium in the coating can be calculated according to the theory of radioactive decay[10] shown in Eq. ( 1 ), in which, m — the mass of uranium. N — the number of uranium nuclei. M — the molar mass, measured in g/mol. N A — the Avogadro’s number, N A =6.022E + 23mol − 1 . T 1/2 — the half-life of radioactive isotopes. ε — the detection efficiency. Δ t — the detection time. Δ N — the number of α particles measured by the detector during Δ t. 3.1 Experimental devices 3.1.1 Devices setup (1)SSA A small solid angle device is designed in Fig. 4 . Uranium coatings and PIPS detectors of Chinese-made FD40 are placed at both ends of the stainless steel container. The diameter of the PIPS detector window is 40mm, the depletion layer thickness is 300µm, and the typical energy resolution under vacuum conditions is better than [email protected] . By recording the α particles emitted by the uranium coating within a small solid angle around 0°, the number of α particles emitted within the 4π solid angle can be calculated. The detection efficiency is ε = Ω /4π, where Ω is the effective solid angle, which is determined by the distance h between the coating and the collimating aperture of the detector, the radius r of the coating active area, and the radius R of the collimating aperture. Considering the detection efficiency and energy resolution, in the experiment, h is 147.7mm, and the container is evacuated to 10Pa. (2)GIC A grid ionization chamber is designed in Fig. 5 . During measurement, the uranium coating is placed at the center of the cathode. The α particles emitted by the uranium coating cause gas ionization in the ionization generation area, generating electron-positron pairs. By recording the pulse signals induced at the anode after the electrons pass through the grid, the number of α particles emitted by the uranium coating within a Δ t time and within an angle of approximately 2π can be obtained[11]. In the experiment, 93%Ar + 7%CO 2 is used as the working gas. The cathode-grid distance is 50mm, to ensure that the energy of the α particles is completely deposited in the signal generation area. The grid is made of gold-plated tungsten wire with a diameter of 0.1mm, and the grid wires are spaced 2mm apart. The device operates in a gas-flow mode under normal temperature and pressure, and the bias of the cathode and anode are set to -1000V and + 1000V, respectively. 3.1.2 Device calibration A 239 Pu (5.16MeV) / 241 Am (5.48MeV) / 244 Cm (5.81MeV) mixed α source is used to calibrate the energy of SSA and GIC, respectively. The pulse amplitude spectras are shown in Fig. 6 , and the linear fitting of the α particle energy and the corresponding channel number is presented in Fig. 7 . 3.2 238 U coating measurement and simulation Figure 8 shows the α energy spectras obtained by SSA and GIC respectively. Two peaks are 4.14MeV-4.19MeV and 4.71MeV-4.77MeV, respectively, corresponding to U 238 and U 234 . The contents of the three isotopes 238 U and 234 U in natural uranium are 99.28% ( 238 U) and 0.006% ( 234 U) respectively. Among them, the half-life of 234 U is three to four orders of magnitude smaller than that of the other isotopes, so the influence of 234 U on α detection cannot be ignored. U 238 and U 234 can be clearly distinguished in the energy spectra measured by both devices. However, the energy resolution of SSA is better. To complement and corroborate the results of the measurements, simulations of the α energy spectra have been performed by the Monte Carlo code GEANT4[12]. The simulated spectrums are shown in Fig. 9 , which are in fair agreement with the measured spectrums. Essentially unlimited statistics can be obtained in the simulations, therefore, the detection efficiency of the device is calculated through simulation. 3.3 results The detection efficiency and measurement results of the two devices are shown in Table 1 . GEANT4 is used to sample 10 9 particles to calculate the detection efficiencies of the two devices respectively. According to Eq. ( 2 ), the masses of 238 U in the U1 coating measured by the two devices are 0.3348mg and 0.3347mg respectively, while the masses of 238 U in the U2 coating are 0.3097mg and 0.3129mg respectively. Table 1 Measurement results uranium coating device Δ N U−238 Δ t /s ε m U−238 /mg U1 SSA 8851 846466 0.00251 0.3348 GIC 9604 4690 0.49157 0.3347 U2 SSA 8767 906149 0.00251 0.3097 GIC 8343 4394 0.49157 0.3129 The parameters that affect the uncertainty of measurement results include M U-238 , N A , T 1/2(U-238) , ε , Δ t , and Δ N U-238 . All these parameters are independent and unrelated to each other. Among them, the uncertainty of the experimental results mainly comes from ε and Δ N U-238 . According to Eq. ( 3 ), it can be calculated that the relative uncertainty of m U-238 in the two coatings measured by the two devices is less than 1.1%. The normalized standard deviation En of m U-238 by the two devices is less than 0.01, the results obtained by the two devices are in good agreement. Table 2 Uncertainties of two devices uranium coating device uncertainty factors u rel ( m U-238 ) u rel (Δ N U−238 ) u rel ( ε ) U1 SSA 1.06% 0.19% 1.08% GIC 1.02% 0.04% 1.02% U2 SSA 1.07% 0.19% 1.08% GIC 1.09% 0.04% 1.09% 4. Conclusion In this paper, natural uranium is used to prepare a 238 U coating on 2µm-thick aluminized mylar foils by electrodeposition. The fabricated coatings are dense and have good uniformity. Mylar film with a thickness of µm, possessing certain ductility and low neutron reaction cross section, serves as the backing for the neutron conversion coatings, effectively reducing interference signals in high-flux neutron beams. The masses of 238 U in the coatings are measured by SSA and GIC respectively. Among them, the energy resolution of SSA is significantly better than that of GIC. The masses of 238 U in the U1 coating measured by the two devices are 0.3348mg and 0.3347mg, respectively, with relative uncertainty of 1.08% and 1.02%. While the masses of 238 U in the U2 coating are 0.3097mg and 0.3129mg, respectively, with relative uncertainty of 1.08% and 1.09%. The normalized standard deviations of the two devices are calculated, and it is found that E n <0.01. Thus, the results obtained by the two devices are consistent within the uncertainties. Declarations Author Contribution H.Y.Y. was responsible for the actual operation process of most of the experiments and wrote the main manuscript text. L.Y.N. and L.Y.T. revised and improved the manuscript. C.K.S. prepared Figures 1-3. L.C.J., B.J., and Y.S.H. provided theoretical support and professional guidance. All the authors reviewed the manuscript. Acknowledgements There is no Funding in the manuscript. References International Atomic Energy Agency[EB/OL]. https://www.iaea.org/. Burattini, P. , Leonardi, S. , Orlandi, P. , & Antonia, R. A. . (2008). Comparison between experiments and direct numerical simulations in a channel flow with roughness on one wall. Journal of Fluid Mechanics, 600, 403-426. Yang, Y. , Wen, Z. , Han, Z. , Wang, M. , Liu, R. , & Wen, J. , et al. (2019). A multi-cell fission chamber for fission cross-section measurements at the back-n white neutron beam of csns. Nuclear Instruments & Methods in Physics Research. Section A, Accelerators, Spectrometers, Detectors and Associated Equipment, 940(OCT.1), 486-491. Paradela, C. , Fujii, K. , Vlastou, R. , Furman, W. , Abbondanno, U. , & Duran, I. , et al. (2010). Neutron-induced fission cross section of u-234 and np-237 measured at the cern neutron time-of-flight (n_tof) facility. Physical Review C, 82(3). Tarrio, D. , Belloni, F. , Berthoumieux, E. , Chiaveri, E. , & Gunsing, F. . (2014). Measurement of the angular distribution of fission fragments using a ppac assembly at cern n_tof. Nuclear Instruments and Methods in Physics Research, Section A. Accelerators, Spectrometers, Detectors and Associated Equipment, 743, 79-85. Kuruc, J. , Dávid Harvan, Dušan Galanda, L’ubomír Mátel, & Monika JerigováDušan Velic. (2011). Alpha spectrometry and secondary ion mass spectrometry of electrodeposited uranium films. Journal of Radioanalytical&Nuclear Chemistry. GEBAUER, & B. (2004). Towards detectors for next generation spallation neutron sources. Nuclear Instruments & Methods in Physics Research, 535(1-2), 65-78. Yi, T. , Xing, P. , Li, C. , Xie, J. , & Li, G. . (2009). Progresses in uranium film fabrication and application. Nuclear Techniques, 32(12), 905-910. Zhang, L. , Wu, X. , Ding, H. , Fan, F. , Bai, J. , & Lin, M. , et al. (2009). The preparation of 238u targets on 2 μm al foils. North-Holland(20). Liu Shengkang. (1986). Neutron Physics. Atomic Energy Press. O. Bunemann, , T. E. Cranshaw, and , J. A. Harvey. (1949). Design of grid ionization chambers. Instruments & Experimental Techniques, 52(52), 260-264. Agostinelli, S. , Allison, J. , Amako, K. , Apostolakis, J. , & Zschiesche, D. . (2003). Geant4—a simulation toolkit. Nuclear Instruments and Methods in Physics Research Section A Accelerators Spectrometers Detectors and Associated Equipment, 506(3), 250. Additional Declarations No competing interests reported. Cite Share Download PDF Status: Posted Version 1 posted You are reading this latest preprint version Research Square lets you share your work early, gain feedback from the community, and start making changes to your manuscript prior to peer review in a journal. As a division of Research Square Company, we’re committed to making research communication faster, fairer, and more useful. We do this by developing innovative software and high quality services for the global research community. Our growing team is made up of researchers and industry professionals working together to solve the most critical problems facing scientific publishing. Also discoverable on Platform About Our Team In Review Editorial Policies Advisory Board Help Center Resources Author Services Accessibility API Access RSS feed Manage Cookie Preferences © Research Square 2026 | ISSN 2693-5015 (online) Privacy Policy Terms of Service Do Not Sell My Personal Information {"props":{"pageProps":{"initialData":{"identity":"rs-7926956","acceptedTermsAndConditions":true,"allowDirectSubmit":true,"archivedVersions":[],"articleType":"Research Article","associatedPublications":[],"authors":[{"id":543777251,"identity":"6ca08220-4159-4376-ae07-c3dee09d5974","order_by":0,"name":"He Yuyang","email":"","orcid":"","institution":"China Institute of Atomic Energy","correspondingAuthor":false,"prefix":"","firstName":"He","middleName":"","lastName":"Yuyang","suffix":""},{"id":543777253,"identity":"bd47e3a7-5979-4843-9d8a-96ef8820844a","order_by":1,"name":"Liu 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07:12:13","extension":"xml","order_by":27,"title":"","display":"","copyAsset":false,"role":"acdc-reference","size":36917,"visible":true,"origin":"","legend":"","description":"","filename":"31554f1dfe094a7f85a1d8963bcd5f011structuring.xml","url":"https://assets-eu.researchsquare.com/files/rs-7926956/v1/63aac045609af58f7dd42366.xml"},{"id":96243154,"identity":"ff03c2ef-a124-44f7-9537-7580a5871a4c","added_by":"auto","created_at":"2025-11-19 07:15:45","extension":"html","order_by":28,"title":"","display":"","copyAsset":false,"role":"acdc-reference","size":43243,"visible":true,"origin":"","legend":"","description":"","filename":"earlyproof.html","url":"https://assets-eu.researchsquare.com/files/rs-7926956/v1/485f77d75fd3c25840a5696b.html"},{"id":95888835,"identity":"13419832-bb38-4259-8a0e-f625b145c5ef","added_by":"auto","created_at":"2025-11-14 05:41:52","extension":"png","order_by":1,"title":"Figure 1","display":"","copyAsset":false,"role":"figure","size":350172,"visible":true,"origin":"","legend":"\u003cp\u003eThe backing prepared using 2μm-thick mylar film\u003c/p\u003e","description":"","filename":"1.png","url":"https://assets-eu.researchsquare.com/files/rs-7926956/v1/a6040449021034f58bf8c74a.png"},{"id":95888870,"identity":"3facdca8-2401-480c-9f07-641aae64521b","added_by":"auto","created_at":"2025-11-14 05:41:55","extension":"png","order_by":2,"title":"Figure 2","display":"","copyAsset":false,"role":"figure","size":487837,"visible":true,"origin":"","legend":"\u003cp\u003eExperimental equipment for uranium coating\u003c/p\u003e","description":"","filename":"2.png","url":"https://assets-eu.researchsquare.com/files/rs-7926956/v1/810564d430cb22ae4a259370.png"},{"id":95888842,"identity":"a1ff97f8-248d-4842-ac9f-091ae2704e43","added_by":"auto","created_at":"2025-11-14 05:41:52","extension":"png","order_by":3,"title":"Figure 3","display":"","copyAsset":false,"role":"figure","size":510914,"visible":true,"origin":"","legend":"\u003cp\u003e\u003csup\u003e238\u003c/sup\u003eU coatings prepared by electrodeposition\u003c/p\u003e","description":"","filename":"3.png","url":"https://assets-eu.researchsquare.com/files/rs-7926956/v1/4aa4ba666207b48dc37c9be2.png"},{"id":95888844,"identity":"4cfc6af4-a134-43e2-8184-d4b2d52e0f41","added_by":"auto","created_at":"2025-11-14 05:41:53","extension":"png","order_by":4,"title":"Figure 4","display":"","copyAsset":false,"role":"figure","size":216282,"visible":true,"origin":"","legend":"\u003cp\u003eThe schematic views of SSA\u003c/p\u003e","description":"","filename":"4.png","url":"https://assets-eu.researchsquare.com/files/rs-7926956/v1/93a87468e11890407f41d488.png"},{"id":96243517,"identity":"753c91d0-6157-49ea-b690-6315872f0b96","added_by":"auto","created_at":"2025-11-19 07:16:35","extension":"png","order_by":5,"title":"Figure 5","display":"","copyAsset":false,"role":"figure","size":40938,"visible":true,"origin":"","legend":"\u003cp\u003eThe schematic views of GIC\u003c/p\u003e","description":"","filename":"5.png","url":"https://assets-eu.researchsquare.com/files/rs-7926956/v1/31260190524ff4e1af971c92.png"},{"id":95888839,"identity":"894b59c4-caa0-4797-893a-57fe8efedffd","added_by":"auto","created_at":"2025-11-14 05:41:52","extension":"png","order_by":6,"title":"Figure 6","display":"","copyAsset":false,"role":"figure","size":137425,"visible":true,"origin":"","legend":"\u003cp\u003eThe pulse amplitude spectra of mixed α source\u003c/p\u003e","description":"","filename":"6.png","url":"https://assets-eu.researchsquare.com/files/rs-7926956/v1/a8ddd6a45f89b4b20965758a.png"},{"id":95888841,"identity":"64ee6dea-2ad9-4b24-81b9-4abbf22fce94","added_by":"auto","created_at":"2025-11-14 05:41:52","extension":"png","order_by":7,"title":"Figure 7","display":"","copyAsset":false,"role":"figure","size":72254,"visible":true,"origin":"","legend":"\u003cp\u003eEnergy calibration curve\u003c/p\u003e","description":"","filename":"7.png","url":"https://assets-eu.researchsquare.com/files/rs-7926956/v1/d497d11d33ba468db6c3e58e.png"},{"id":95888871,"identity":"7daa04b7-77d0-4a49-9548-08cc67f0761d","added_by":"auto","created_at":"2025-11-14 05:41:55","extension":"png","order_by":8,"title":"Figure 8","display":"","copyAsset":false,"role":"figure","size":267654,"visible":true,"origin":"","legend":"\u003cp\u003eα energy measured spectrum obtained from the uranium coating\u003c/p\u003e","description":"","filename":"8.png","url":"https://assets-eu.researchsquare.com/files/rs-7926956/v1/e3b0a4b41bb712a59fdc0377.png"},{"id":96242357,"identity":"dbdffb80-dd15-43e6-97b7-0876594dfc23","added_by":"auto","created_at":"2025-11-19 07:12:47","extension":"png","order_by":9,"title":"Figure 9","display":"","copyAsset":false,"role":"figure","size":113431,"visible":true,"origin":"","legend":"\u003cp\u003eα energy simulated spectrum obtained from the uranium coating\u003c/p\u003e","description":"","filename":"9.png","url":"https://assets-eu.researchsquare.com/files/rs-7926956/v1/ae8b6faa39f3786a31dadb89.png"},{"id":98433334,"identity":"a14cf131-e41f-4675-bd1c-ad9df0246650","added_by":"auto","created_at":"2025-12-17 16:50:39","extension":"pdf","order_by":0,"title":"","display":"","copyAsset":false,"role":"manuscript-pdf","size":3206736,"visible":true,"origin":"","legend":"","description":"","filename":"manuscript.pdf","url":"https://assets-eu.researchsquare.com/files/rs-7926956/v1/272f4a25-d380-4273-b09a-31dca7ff9dee.pdf"}],"financialInterests":"No competing interests reported.","formattedTitle":"\u003cp\u003ePreparation and Accurate Quantification of \u003csup\u003e238\u003c/sup\u003eU Coatings on Thin-Backed\u003c/p\u003e","fulltext":[{"header":"1. Introduction","content":"\u003cp\u003eUranium isotopes play a crucial role in neutron physics[1]. Fission ionization chambers based on nuclear fission reactions such as \u003csup\u003e235\u003c/sup\u003eU(n,f) and \u003csup\u003e238\u003c/sup\u003eU(n,f) are widely applied in neutron detection. They exhibit excellent n-γ discrimination capability, are free from radiation damage issues, and feature flexible and diverse structures[2,3]. The uranium coating is one of the important components for the fission ionization chamber. The measurement results such as neutron-induced fission cross section and neutron flux are directly related to the number of target nuclei in the fission coating[4,5]. Therefore, it is necessary to conduct an accurate quantitative analysis of the uranium coating. Uranium isotopes can generate alpha particles through spontaneous decay. Thus, the alpha spectrometry method[6] is widely used for the quantitative analysis of uranium in the coating, which is to obtain the uranium content in the coating by measuring the count rate of alpha particles.\u003c/p\u003e\u003cp\u003eWith the significant improvement in the performance and neutron flux of the new generation of neutron science devices, neutron detectors are required to exhibit excellent performance under high-flux neutron beams[7]. To avoid strong interference signals caused by the interaction of neutrons or secondary particles with other substances outside the target nucleus, the amount of material in the beam should be minimized. In this paper, \u003csup\u003e238\u003c/sup\u003eU coating is prepared on a 2\u0026micro;m-thick aluminized mylar foils by electrodeposition. This foil has good ductility and a low neutron reaction cross-section. Quantitative measurements of the \u003csup\u003e238\u003c/sup\u003eU are conducted using two devices based on alpha spectrometry method, which are called the small solid angle device (SSA) and the grid ionization chamber (GIC). And uncertainty analysis is performed. The results of two devices are consistent within the uncertainties.\u003c/p\u003e"},{"header":"2. Preparation of U coating on thin-backing","content":"\u003cp\u003eFor neutron detectors used in high-flux neutron beams, a cathode for the ionization chamber is prepared using a \u0026micro;m-thick aluminized mylar foil as the backing. This material has certain ductility and a low neutron reaction cross-section, which can effectively reduce interference signals and achieve neutron detection in the beam line. Figure\u0026nbsp;\u003cspan refid=\"Fig1\" class=\"InternalRef\"\u003e1\u003c/span\u003e shows the backing made by bonding a PCB ring and a 2\u0026micro;m-thick mylar film using specialized tooling. The ductility of the mylar film results in a smooth mirror-like effect on the backing.\u003c/p\u003e\u003cp\u003e\u003c/p\u003e\u003cp\u003eTo preparing \u003csup\u003e238\u003c/sup\u003eU coating on thin-backing by electrodeposition[8,9], a experimental equipment has been designed in Fig.\u0026nbsp;\u003cspan refid=\"Fig2\" class=\"InternalRef\"\u003e2\u003c/span\u003e. The aluminized mylar foil serves as the cathode, and the platinum wire with a diameter of 1mm is used as the anode. By bending the platinum wire into a concentric circular with a maximum diameter of 40mm, a dense and highly uniform metal coating can be obtained. The distance between adjacent concentric rings is 2mm, which can effectively prevent the gas generated by the cathodic hydrogen evolution reaction from damaging the substrate and affecting the uniformity of the coating.\u003c/p\u003e\u003cp\u003e\u003c/p\u003e\u003cp\u003eIn the experiment, natural uranium is dissolved in concentrated nitric acid, dried to form uranyl nitrate (UO\u003csub\u003e2\u003c/sub\u003e(NO\u003csub\u003e3\u003c/sub\u003e)\u003csub\u003e2\u003c/sub\u003e\u0026middot;6H\u003csub\u003e2\u003c/sub\u003eO), and then dissolve in dilute nitric acid solution to prepare uranium feed solution for later use. An isopropanol solution is used as the electroplating solution to dissolve the uranium solution as the electrolyte, and the initial pH value of the electrolyte is adjusted with nitric acid solution. The obtained \u003csup\u003e238\u003c/sup\u003eU coatings are shown in Fig.\u0026nbsp;\u003cspan refid=\"Fig3\" class=\"InternalRef\"\u003e3\u003c/span\u003e, with the active area diameter of the coatings being 30mm.\u003c/p\u003e\u003cp\u003e\u003c/p\u003e"},{"header":"3. Quantification of U in coatings","content":"\u003cp\u003eThe \u0026alpha; particles emitted during the decay of the uranium nucleus are isotropic. Therefore, as long as the number of \u0026alpha; particles emitted by the uranium coating in a certain direction and solid angle is measured, the total number of \u0026alpha; particles emitted by the uranium within the coating can be obtained. Thereby, the mass of uranium in the coating can be calculated according to the theory of radioactive decay[10] shown in Eq. (\u003cspan class=\"InternalRef\"\u003e1\u003c/span\u003e),\u003c/p\u003e\n\u003cdiv id=\"Equ1\" class=\"Equation\"\u003e\n \u003cdiv class=\"EquationNumber\"\u003e\u003cimg src=\"data:image/png;base64,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\" width=\"516\" height=\"72\"\u003e\u003c/div\u003e\n\u003c/div\u003e\n\u003cp\u003ein which,\u003c/p\u003e\n\u003cp\u003e\u003cem\u003em\u003c/em\u003e \u0026mdash; the mass of uranium.\u003c/p\u003e\n\u003cp\u003e\u003cem\u003eN\u003c/em\u003e \u0026mdash; the number of uranium nuclei.\u003c/p\u003e\n\u003cp\u003e\u003cem\u003eM\u003c/em\u003e \u0026mdash; the molar mass, measured in g/mol.\u003c/p\u003e\n\u003cp\u003e\u003cem\u003eN\u003c/em\u003e\u003csub\u003e\u003cem\u003eA\u003c/em\u003e\u003c/sub\u003e \u0026mdash; the Avogadro\u0026rsquo;s number, N\u003csub\u003eA\u003c/sub\u003e=6.022E\u0026thinsp;+\u0026thinsp;23mol\u003csup\u003e\u0026minus;\u0026thinsp;1\u003c/sup\u003e.\u003c/p\u003e\n\u003cp\u003e\u003cem\u003eT\u003c/em\u003e\u003csub\u003e1/2\u003c/sub\u003e \u0026mdash; the half-life of radioactive isotopes.\u003c/p\u003e\n\u003cp\u003e\u003cem\u003e\u0026epsilon;\u003c/em\u003e \u0026mdash; the detection efficiency.\u003c/p\u003e\n\u003cp\u003e\u0026Delta;\u003cem\u003et\u003c/em\u003e \u0026mdash; the detection time.\u003c/p\u003e\n\u003cp\u003e\u0026Delta;\u003cem\u003eN\u003c/em\u003e \u0026mdash; the number of \u0026alpha; particles measured by the detector during \u0026Delta;\u003cem\u003et.\u003c/em\u003e\u003c/p\u003e\n\u003cdiv id=\"Sec4\" class=\"Section2\"\u003e\n \u003ch2\u003e3.1 Experimental devices\u003c/h2\u003e\n \u003cdiv id=\"Sec5\" class=\"Section3\"\u003e\n \u003ch2\u003e3.1.1 Devices setup\u003c/h2\u003e\n \u003cp\u003e(1)SSA\u003c/p\u003e\n \u003cp\u003eA small solid angle device is designed in Fig. \u003cspan class=\"InternalRef\"\u003e4\u003c/span\u003e. Uranium coatings and PIPS detectors of Chinese-made FD40 are placed at both ends of the stainless steel container. The diameter of the PIPS detector window is 40mm, the depletion layer thickness is 300\u0026micro;m, and the typical energy resolution under vacuum conditions is better than [email protected]. By recording the \u0026alpha; particles emitted by the uranium coating within a small solid angle around 0\u0026deg;, the number of \u0026alpha; particles emitted within the 4\u0026pi; solid angle can be calculated. The detection efficiency is \u003cem\u003e\u0026epsilon;\u0026thinsp;=\u0026thinsp;Ω\u003c/em\u003e/4\u0026pi;, where \u003cem\u003eΩ\u003c/em\u003e is the effective solid angle, which is determined by the distance \u003cem\u003eh\u003c/em\u003e between the coating and the collimating aperture of the detector, the radius \u003cem\u003er\u003c/em\u003e of the coating active area, and the radius \u003cem\u003eR\u003c/em\u003e of the collimating aperture. Considering the detection efficiency and energy resolution, in the experiment, \u003cem\u003eh\u003c/em\u003e is 147.7mm, and the container is evacuated to 10Pa.\u003c/p\u003e\n \u003cp\u003e(2)GIC\u003c/p\u003e\n \u003cp\u003eA grid ionization chamber is designed in Fig. \u003cspan class=\"InternalRef\"\u003e5\u003c/span\u003e. During measurement, the uranium coating is placed at the center of the cathode. The \u0026alpha; particles emitted by the uranium coating cause gas ionization in the ionization generation area, generating electron-positron pairs. By recording the pulse signals induced at the anode after the electrons pass through the grid, the number of \u0026alpha; particles emitted by the uranium coating within a \u0026Delta;\u003cem\u003et\u003c/em\u003e time and within an angle of approximately 2\u0026pi; can be obtained[11].\u003c/p\u003e\n \u003cp\u003eIn the experiment, 93%Ar\u0026thinsp;+\u0026thinsp;7%CO\u003csub\u003e2\u003c/sub\u003e is used as the working gas. The cathode-grid distance is 50mm, to ensure that the energy of the \u0026alpha; particles is completely deposited in the signal generation area. The grid is made of gold-plated tungsten wire with a diameter of 0.1mm, and the grid wires are spaced 2mm apart. The device operates in a gas-flow mode under normal temperature and pressure, and the bias of the cathode and anode are set to -1000V and +\u0026thinsp;1000V, respectively.\u003c/p\u003e\n \u003c/div\u003e\n \u003cdiv id=\"Sec6\" class=\"Section3\"\u003e\n \u003ch2\u003e3.1.2 Device calibration\u003c/h2\u003e\n \u003cp\u003eA \u003csup\u003e239\u003c/sup\u003ePu (5.16MeV) / \u003csup\u003e241\u003c/sup\u003eAm (5.48MeV) / \u003csup\u003e244\u003c/sup\u003eCm (5.81MeV) mixed \u0026alpha; source is used to calibrate the energy of SSA and GIC, respectively. The pulse amplitude spectras are shown in Fig. \u003cspan class=\"InternalRef\"\u003e6\u003c/span\u003e, and the linear fitting of the \u0026alpha; particle energy and the corresponding channel number is presented in Fig. \u003cspan class=\"InternalRef\"\u003e7\u003c/span\u003e.\u003c/p\u003e\n \u003c/div\u003e\n\u003c/div\u003e\n\u003cdiv id=\"Sec7\" class=\"Section2\"\u003e\n \u003ch2\u003e3.2 \u003csup\u003e238\u003c/sup\u003eU coating measurement and simulation\u003c/h2\u003e\n \u003cp\u003eFigure \u003cspan class=\"InternalRef\"\u003e8\u003c/span\u003e shows the \u0026alpha; energy spectras obtained by SSA and GIC respectively. Two peaks are 4.14MeV-4.19MeV and 4.71MeV-4.77MeV, respectively, corresponding to U\u003csup\u003e238\u003c/sup\u003e and U\u003csup\u003e234\u003c/sup\u003e. The contents of the three isotopes \u003csup\u003e238\u003c/sup\u003eU and \u003csup\u003e234\u003c/sup\u003eU in natural uranium are 99.28% (\u003csup\u003e238\u003c/sup\u003eU) and 0.006% (\u003csup\u003e234\u003c/sup\u003eU) respectively. Among them, the half-life of \u003csup\u003e234\u003c/sup\u003eU is three to four orders of magnitude smaller than that of the other isotopes, so the influence of \u003csup\u003e234\u003c/sup\u003eU on \u0026alpha; detection cannot be ignored. U\u003csup\u003e238\u003c/sup\u003e and U\u003csup\u003e234\u003c/sup\u003e can be clearly distinguished in the energy spectra measured by both devices. However, the energy resolution of SSA is better.\u003c/p\u003e\n \u003cp\u003eTo complement and corroborate the results of the measurements, simulations of the \u0026alpha; energy spectra have been performed by the Monte Carlo code GEANT4[12]. The simulated spectrums are shown in Fig. \u003cspan class=\"InternalRef\"\u003e9\u003c/span\u003e, which are in fair agreement with the measured spectrums. Essentially unlimited statistics can be obtained in the simulations, therefore, the detection efficiency of the device is calculated through simulation.\u003c/p\u003e\n\u003c/div\u003e\n\u003cdiv id=\"Sec8\" class=\"Section2\"\u003e\n \u003ch2\u003e3.3 results\u003c/h2\u003e\n \u003cp\u003eThe detection efficiency and measurement results of the two devices are shown in Table \u003cspan class=\"InternalRef\"\u003e1\u003c/span\u003e. GEANT4 is used to sample 10\u003csup\u003e9\u003c/sup\u003e particles to calculate the detection efficiencies of the two devices respectively. According to Eq. (\u003cspan class=\"InternalRef\"\u003e2\u003c/span\u003e), the masses of \u003csup\u003e238\u003c/sup\u003eU in the U1 coating measured by the two devices are 0.3348mg and 0.3347mg respectively, while the masses of \u003csup\u003e238\u003c/sup\u003eU in the U2 coating are 0.3097mg and 0.3129mg respectively.\u003c/p\u003e\n \u003cdiv id=\"Equ2\" class=\"Equation\"\u003e\n \u003cdiv class=\"EquationNumber\"\u003e\u003cimg src=\"data:image/png;base64,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\" width=\"553\" height=\"67\"\u003e\u003c/div\u003e\n \u003c/div\u003e\n \u003cdiv class=\"gridtable\"\u003e\n \u003ctable id=\"Tab1\" border=\"1\"\u003e\n \u003ccaption language=\"En\"\u003e\n \u003cdiv class=\"CaptionNumber\"\u003eTable 1\u003c/div\u003e\n \u003cdiv class=\"CaptionContent\"\u003e\n \u003cp\u003eMeasurement results\u003c/p\u003e\n \u003c/div\u003e\n \u003c/caption\u003e\n \u003cthead\u003e\n \u003ctr\u003e\n \u003cth align=\"left\"\u003e\n \u003cp\u003euranium coating\u003c/p\u003e\n \u003c/th\u003e\n \u003cth align=\"left\"\u003e\n \u003cp\u003edevice\u003c/p\u003e\n \u003c/th\u003e\n \u003cth align=\"left\"\u003e\n \u003cp\u003e\u0026Delta;\u003cem\u003eN\u003c/em\u003e\u003csub\u003eU\u0026minus;238\u003c/sub\u003e\u003c/p\u003e\n \u003c/th\u003e\n \u003cth align=\"left\"\u003e\n \u003cp\u003e\u0026Delta;\u003cem\u003et\u003c/em\u003e/s\u003c/p\u003e\n \u003c/th\u003e\n \u003cth align=\"left\"\u003e\n \u003cp\u003e\u003cem\u003e\u0026epsilon;\u003c/em\u003e\u003c/p\u003e\n \u003c/th\u003e\n \u003cth align=\"left\"\u003e\n \u003cp\u003e\u003cem\u003em\u003c/em\u003e\u003csub\u003eU\u0026minus;238\u003c/sub\u003e/mg\u003c/p\u003e\n \u003c/th\u003e\n \u003c/tr\u003e\n \u003c/thead\u003e\n \u003ctbody\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\" rowspan=\"2\"\u003e\n \u003cp\u003eU1\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eSSA\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e8851\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e846466\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e0.00251\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e0.3348\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eGIC\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e9604\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e4690\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e0.49157\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e0.3347\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\" rowspan=\"2\"\u003e\n \u003cp\u003eU2\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eSSA\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e8767\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e906149\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e0.00251\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e0.3097\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eGIC\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e8343\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e4394\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e0.49157\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e0.3129\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003c/tbody\u003e\n \u003c/table\u003e\n \u003c/div\u003e\n \u003cp\u003e\u003cbr\u003e\u003c/p\u003e\n \u003cp\u003eThe parameters that affect the uncertainty of measurement results include \u003cem\u003eM\u003c/em\u003e\u003csub\u003eU-238\u003c/sub\u003e, \u003cem\u003eN\u003c/em\u003e\u003csub\u003e\u003cem\u003eA\u003c/em\u003e\u003c/sub\u003e, \u003cem\u003eT\u003c/em\u003e\u003csub\u003e1/2(U-238)\u003c/sub\u003e, \u003cem\u003e\u0026epsilon;\u003c/em\u003e, \u0026Delta;\u003cem\u003et\u003c/em\u003e, and \u0026Delta;\u003cem\u003eN\u003c/em\u003e\u003csub\u003eU-238\u003c/sub\u003e. All these parameters are independent and unrelated to each other. Among them, the uncertainty of the experimental results mainly comes from \u003cem\u003e\u0026epsilon;\u003c/em\u003e and \u0026Delta;\u003cem\u003eN\u003c/em\u003e\u003csub\u003eU-238\u003c/sub\u003e. According to Eq.\u0026nbsp;(\u003cspan class=\"InternalRef\"\u003e3\u003c/span\u003e), it can be calculated that the relative uncertainty of \u003cem\u003em\u003c/em\u003e\u003csub\u003eU-238\u003c/sub\u003e in the two coatings measured by the two devices is less than 1.1%. The normalized standard deviation \u003cem\u003eEn\u003c/em\u003e of \u003cem\u003em\u003c/em\u003e\u003csub\u003eU-238\u003c/sub\u003e by the two devices is less than 0.01, the results obtained by the two devices are in good agreement.\u003c/p\u003e\n \u003cdiv id=\"Equ3\" class=\"Equation\"\u003e\n \u003cdiv class=\"EquationNumber\"\u003e\u003cimg src=\"data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAAAkcAAAAzCAYAAACdb6wJAAAAAXNSR0IArs4c6QAAAARnQU1BAACxjwv8YQUAAAAJcEhZcwAAFiUAABYlAUlSJPAAABLkSURBVHhe7d1fTFPnGwfwb43GX0wBY7mg4I01SLwBKxPnogYpDBCXkGXOjhjQiJq5xMFUBlvmn/2Jm1LlZiwqJqKMlLELwz+JCjrHbqy0QrIQ6IpmWssSq8H2Ynfnd7Gek9OXtvQcTk8LPJ+Em/c91NfnOe/hPe/7nlMNx3EcCCGEEEIIAGAJW0AIIYQQspjR4IgQQgghRIQGR4QQQgghIjQ4IoQQQggRocERIYQQQogIDY4IIYQQQkRocEQIIYQQIkKDI0IIIYQQERocEUIIIYSI0OCIEEIIIUSEBkeEEEIIISI0OCKEEEIIEaHBESGEEEKIiIbjOI4tJPObRqNhiwghZMGiP2NEaTQ4WoA0Gg1dLAghhBCZaFmNEEIIIUSEBkeEEEIIISI0OFpgxEtqPT090Gg0ws/atWvh8XjYXyFkXnI4HEhNTRXO79TUVDgcDvj9fhQWFgaVxQL1L+WFyunvv/+uSj4JEYvL4OiXX36B0+lki+cdh8OBlpYWtjjhdHd3g+M4uFwu6PV6tlqWhZJDOeKVd4p5cMyNRiNevnwJjuPQ3d0tlFutVpw/fx4cx6GsrAwnTpyA3+8P+l0lxaJ/QUa+Q8VILUq1NVROu7q6VM0nSSxWqxUjIyNssWR9fX0YGhpii8NSfXDU0tKCFStWIDMzk62ad4xGI9LS0kJ28oVsIeVQjnjknWIefcyrq6thNBoBADU1NXjz5g18Ph97WEKTk28pMVJSrNtaUVEx7/NJpPN6vSgpKcGDBw+Qk5PDVku2efNm1NbW4siRI2xVSKoOjnp6ejA9PY1du3axVfPWrl27MDY2hp6eHrZqQVqIOZRDzbxTzP8jN+Zr1qxBUlISW5yw5pJvuTGSKx5tnW/5JNLxA6N9+/ahubmZrRZ8+eWXWLVqFTQaDTZt2oS+vj72EIFOp4PNZgOAqAZIqg2OPB4P2traUFFRwVbNe3v37sXXX3+94PcbLOQcyqFG3inmwaTG3O12Iy8vD1qtlq1KSErkW2qM5IpHW+dbPok8JSUlePfdd2E2m9kqgdlshsvlQn19Pfbs2YNHjx6hrKxs1qWz5uZm2Gy2WQdIqg2O2tvbsXz5ckXX5BOF0WjE+vXr0d7ezlbNG319fSgtLQ3aDHno0CE4nU5hf4CUHD548CDsHgTxhtlIG1nZzZkajQZVVVXsYXGjRt6jjXmkeGORxtzj8aCrqwuHDx9mq1QXTf+ChHxHIiVGc6F2WxMpnyR2zp07BwD47rvv2CqB1WpFeXk5rFYr6urqYLVa8cMPPwCB83I2/f39sFqtEWeaVBkc+f1+3Lp1C9nZ2WzVgpGdnY1bt27FdaOgRsbLH/v6+pCXl4fa2lpUVVXh6dOn4DgOHMehoKAAW7ZswcaNG6HVaiXl8OrVq+jq6mKLAQBarRZ3797FxMQETCYTJicnQ57QRqMRT58+xfvvvw+TyYSJiQm0trayh8VVLPMupd9EijcWacwvX76MM2fOxHWWIdr+lZaWJinfs4k2RnLFo62JkE8SW16vF99//z0uXrzIVgUpKiqaMat04MABAMCrV6+CykPR6XSor6/H0aNH2SqBKoOj+/fv4/HjxygoKGCrFoyCggI8e/Ys4t17orFYLCgrK0NycjKGh4dhNpuDLjxmsxkNDQ0wGAzw+/1R59DhcKC3txfNzc0hZyd4mZmZyMjIAICwF0etVgutVouamhpJGz7VEsu8R9tvoo03FlHMLRYLcnNzodfrwz4ZFWtS+ldubm7U+Y5GNDGaC7Xbmgj5JLF3584dAMDWrVvZqiA6nY4twvPnzwEA5eXlbFVIBw4cgMvlCjt7pMrgaHx8HCkpKUhLS2OrFhSv14vBwUG2OCFZLBYcP34cJpMJN2/eDHs3VlBQgLfeegsejyfqHLa1tcHr9WJychLDw8NstcDv92P58uUoLCzEwMAA7t+/zx4Cj8eDFy9eIDc3l61KGLHKe7T9Jtp4Y5HEvKqqCsePH8d7770HjUaDoqIi1f8vUvtXUlJS1PmOVqQYzZWaba2trY17Pok6/v77b+Tl5bHFUTl79iz27NkzY0YpHJ1Oh+LiYvzxxx9sFaDG4Iiffl3o0tLSkJKSgtHRUbYq4TgcDpw9exY6nQ7nz58Pe+FG4P/1zjvv4LfffmOrQvJ4PPD5fLhy5QoAoLOzkz1E4HQ6MT09jZMnT0Kn06GpqWnGTMbw8DDS09PntK8hlmKV92j7jZR4Y5HEvLW1VVi64jgOL1++FB4Fj4bFYpnTPiup/auoqAgIzOQpZbYYzUW052a0ZmvrxYsX55RPsrCNjIzAbDbj9u3baGhoYKsjWrlyZdgbStmDI7/fj2PHjkGj0cBisQTVWSwW4U2mPp8PT548Cfv4ZVVVlbBBkf8cfp1e/DZU8b937Ngx5lPiLykpCWvWrIHb7Z7xxybRNDU1wev1oqGhYdaLjF6vx4cffhgxh2Lt7e3IyspCWVkZDAYDent7hRyyBgcHkZeXh23btqGsrAyPHz+eMbU+Pj6uyL6GWJGad6X6DU9KvLFIY642qf2ruro66nw7nU4cOnQoaGN3Xl7ejBzKiZHS52Ys20oIApu3N2zYgI6ODrx+/Ro7duyA1WplDwtr48aNbJFA9uDIYrFg8+bN0Ol0M0b8o6OjUU+5tra2Cm9CzcrKwoMHDwAAJ0+eFKZa/X4/rl69ihMnTsBkMmFkZCRhO9GTJ08S+gVl/P4UnU6nyH4BMY/HA5vNhoqKCuj1emzdujXidPno6CiysrIAALt374bX60VTU5NQ7/f78fDhQ8XbGQvR5l2pfgMZ8cYijbmaYtm/LBYL1q1bh4yMDGFj92effQabzYZvv/2WPRyQGCMlz81Yt5UsTCkpKfjrr7/Y4rDq6urAcRx6e3tRXFyM169f48iRI/B6veyhIdntdqxcuZItBuQOjpxOJyoqKrBixQp4vd6gu0y/3w+3242tW7dCr9djamoK09PTyMjICDu9PD4+DoPBgCVLlmBiYgI7d+4U6jIyMtDR0YEDBw6A4zg8efIk6HcTzfT0NKampoLKLBaLcOc02w97xxYtTZRPqg0ODsLr9WLDhg1Rb7aNJocILMdkZGQIyzE1NTXQ6XQhNwqz+1ry8/NhMpmCZj74O8xo2xlPofLOUrrfSIk3FmnM1SanfyGKPubxeNDc3IzKykqcOnVKOGbHjh3Q6XTYvXs3+yuAhBgpeW7Guq1k4SoqKoLL5cLk5CRbFdHOnTvR398vDJD4jd2zefToUdjZI1mDo8zMTGRmZmJ8fHzGHZLT6cTjx4/DdgCWP7B+bTAY4PF4UF1dDQT2Tuh0Ovzzzz/Yvn07tFqt0ClLS0tDdspEdezYsaA180g/sV4y5O8Iw13Y5PL7/bhx4wb27t0rlGVmZmLDhg0hNwpPTU0hOztb+MOu1WpRWloaNPPhdrvxv//9T9F2xpPS/UZKvLFIY662WPUvfunJ7/cHzZrv2rULL1++lPWGajElz81Yt5UsXAaDAR9//DG++OILtioq/KP509PTbNUMQ0NDcLlcKC4uZqsAuYMjiAY17B0SP0XPPy7MC7eezK9fL126VJgx8ng8GBoagsFgEDotAndlCDzhQdQXLocIXEBXr14dtMeC/+OLEBuFBwcHkZ6eHlRWUVEBg8EgzHx0dnZGfUFOJD09PUhNTQ050FWq30iNNxZ4zOUKNat7/PhxXL9+fUb5XDZpRytcvrVaLX766Sc8e/YMSUlJ0ER4kWckapybSrWVLE7ffPMNbt++jUuXLrFVs0pOTgYAvP3222xVEK/Xi9raWhQXF4f93jbZgyP+bkI8i+N0OjE2NhbUufgnEcIZHh7G5OQkCgsLhTtafoYoOTlZuPjzHVfKunc8JHr75Gy0nS2HCFxAd+zYwRYLf3zFSzf+MPta9Ho9jhw5gsnJSfT29ib84+Ri0eZdqX4jJd5Y5DGPJNSsbmNjIyorK2eUR/MyTDn9C7Pk2x/YKL1lyxacPn1aaI/L5Zr1iUIpMVLi3FSrrWTh0ul0uHfvHhoaGoS3ZUfrzz//jDjg4X311VdwuVz4+eef2SqB7MERO4vj9/vR19eH5ORkSVPK/PKZ+KLNr9uXlpYKHYrvuPy693wS6u403E+4PUfiY+aioKAAOp0OQ0NDs97J9fT0CBvkI3E4HPj333+Rn5/PVoXcKOzz+fDq1auQF0K+fQcPHgTHcRGfhklU/PJBqFwq0W+kxhuLIOaJIhb965NPPsGFCxdw7dq1oP2YcsT63FSyrWTxysnJwb1799DZ2YmSkpIZG6zNZjNWrVqFc+fOCXWXLl1CS0tLxC+qReBLZ61WK+7duwddiJdJ8mQNjkJNv3Z0dGDjxo0z1qb59edQTyL4Axv92Gnc0dFRGAyGoC80dLvd8Hq92LZtG9auXTtjMOHxeITywsLCkNO9ftH3S4lfEwDRACZceaSBC0TLg6EGb6HuTsP9hJru1gQ2W3OBDddzGSAZjUaUlZVhcnIS9fX1bLXA4XBgamoK27dvj5hDiB4PD3fxZDcKR3qPDt8+AEF3sOL8Ssl7LHOOWfLOUqrfSI03Znl30UKOudrk9C9EyLd4i4F4Ro+PcbjlKqkxUuLcVKutZHHIycmBzWZDQUEBxsbGgur4t2B//vnnSE1NxaZNmzA9PY3+/n4YDIagY3lerxclJSWw2Wx49OjRrLNLsgZH/MnMr0FfvXoVO3fuxMOHDwEAS5YsEb4bRbwPghVqGpfvYGxH6ezshMFgQHp6Oo4ePQqTyYTu7m5hMKHX6zE0NITTp0/j7t27If9wWK1WnD9/HhzHoaysDCdOnIDf74fD4UBKSgo4jkNDQ4Owxu7xeNDR0QG73Q673Y7Lly8HXdBDkTutHgk/KAqHHzxF68cff4TJZML169dRWFgoPKGEwJLmxYsX0dbWJmyOj5RDj+hx8nDEG4V//fVXNDU1ITU1lT1MsHv37hmziXq9HiMjI5LzrkbOEWXeleg3UuM9PDwMp9O5aGMeD1L7FyLkmzc5OSm8iNXpdKK8vBwDAwMoLy+POKCINkZKnJu8WLeVLC51dXUzvk7EbDbj1atXwqSBzWZDXV1dxJmgO3fuYN++fbDZbGEHUGKyBkf8ncP169dx6tQp7NmzRzjpvV4vBgYGcPDgQeH4goICLF26dMZjmm63W6jn8XuQQm0KnZ6exps3b4QvmGMlJSVh9erVbLGgurpa2MNUU1ODN2/ewOfzwWg0CheqrKwsoZPy7U1LS4u4zo7AsUuXLp2xp0NpSsweaQNfQtrb24tly5Zh3bp1wl37/v37kZ+fP+PuPVwO29vb0dHRgfT0dOEz2J+kpCQMDAwAgacJBgYGcOHChbB3kvn5+di/f3/IJaBQIuU9ljmHxLwr0W+kxvuDDz7AunXrFm3M40FO/0KYfOv1evT392PTpk346KOPoNFosGXLFixbtgx2uz3k50BGjJQ4N9VqKyFymM3mqL9aBPjvj23M+Xw+zmQycY2NjWyVLPzndXd3zyhvaWkJKgvHbrdzH374Iefz+YQy9vf5f6eyspLr7u6O2P7GxkbOZDIFfV6sAODEqQuXxu7ubg7AjDjJoXQO5Zhr3pXOORfjvFPMQwsV8+7ubk6n03F2uz3o2FhSsn9xCuc7VIyUpEZb45FTQniyZo6k4qdh2beuxpPb7Q7at+HxeJCTk4Pq6mrhDker1eLGjRsYGhpCZ2dnyP1AvNHR0aDlwYUmEXMoldI5R4zzTjEPLZYxjycl8x3rGM2nthIihyqDIwQeMR4bG4tqL0GseTwedHV14fDhw0KZXq+Hy+VCY2Nj0EbW3t5eXLt2DW63O+TmUwQ+78WLFxH3gShJiaU1ORIph1IpnXOolHeKeTA1Yh5PSuRbrRjNp7YSIpVqgyO9Xo+TJ0+ira2NrZJMq9UiIyMD4+PjQeU+nw/Pnz8HmC+0ZV/edvnyZZw5cybknQr/nhgEnii5c+cOjEYjbt68CQC4f/8+8xv/7QP59NNPI242XAiUzKEcc8m70jmHSnmnmAdTI+bxpES+1YrRfGorIVKpNjhC4B0b69evR09PD1slWXZ29ozvkKqvrxceIW1tbRV2sotf3maxWJCbmwu9Xg+Hw4GWlhahDiEeeeYfV+Wf5mD19PQgJSUlbq/E10h8Um2ulMyhHHLyrnTOoXLeKeb/UTPm8TSXfKsdo/nUVkIkYTchqaGjo4ObmJhgiyWrrKwUNicDmHVzIHs8v9mvsbFRKKusrAz6HXEd+/l2u527cuVKUJma+HaFw28Y5X8MBgP34sUL9jBZlMqhHGwe2byIscfONedcHPNOMQ+Oud1u53Q63Yx/Ry2x7F+cjHyHipFalGprvHNKCE/DqTntQBTF7zmiFBJCCCHKUXVZjRBCCCEk0dHMESGEEEKICM0cEUIIIYSI0OCIEEIIIUSEBkeEEEIIISI0OCKEEEIIEfk/9goeXWm5CPEAAAAASUVORK5CYII=\" width=\"583\" height=\"51\"\u003e\u003c/div\u003e\n \u003c/div\u003e\n \u003cdiv class=\"gridtable\"\u003e\n \u003ctable id=\"Tab2\" border=\"1\"\u003e\n \u003ccaption language=\"En\"\u003e\n \u003cdiv class=\"CaptionNumber\"\u003eTable 2\u003c/div\u003e\n \u003cdiv class=\"CaptionContent\"\u003e\n \u003cp\u003eUncertainties of two devices\u003c/p\u003e\n \u003c/div\u003e\n \u003c/caption\u003e\n \u003ctbody\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\" rowspan=\"2\"\u003e\n \u003cp\u003euranium coating\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" rowspan=\"2\"\u003e\n \u003cp\u003edevice\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" colspan=\"2\"\u003e\n \u003cp\u003euncertainty factors\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" rowspan=\"2\"\u003e\n \u003cp\u003e\u003cem\u003eu\u003c/em\u003e\u003csub\u003erel\u003c/sub\u003e(\u003cem\u003em\u003c/em\u003e\u003csub\u003eU-238\u003c/sub\u003e)\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e\u003cem\u003eu\u003c/em\u003e\u003csub\u003erel\u003c/sub\u003e(\u0026Delta;\u003cem\u003eN\u003c/em\u003e\u003csub\u003eU\u0026minus;238\u003c/sub\u003e)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e\u003cem\u003eu\u003c/em\u003e\u003csub\u003erel\u003c/sub\u003e(\u003cem\u003e\u0026epsilon;\u003c/em\u003e)\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\" rowspan=\"2\"\u003e\n \u003cp\u003eU1\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eSSA\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e1.06%\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e0.19%\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e1.08%\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eGIC\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e1.02%\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e0.04%\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e1.02%\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\" rowspan=\"2\"\u003e\n \u003cp\u003eU2\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eSSA\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e1.07%\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e0.19%\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e1.08%\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eGIC\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e1.09%\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e0.04%\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e1.09%\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003c/tbody\u003e\n \u003c/table\u003e\n \u003c/div\u003e\n\u003c/div\u003e"},{"header":"4. Conclusion","content":"\u003cp\u003eIn this paper, natural uranium is used to prepare a \u003csup\u003e238\u003c/sup\u003eU coating on 2\u0026micro;m-thick aluminized mylar foils by electrodeposition. The fabricated coatings are dense and have good uniformity. Mylar film with a thickness of \u0026micro;m, possessing certain ductility and low neutron reaction cross section, serves as the backing for the neutron conversion coatings, effectively reducing interference signals in high-flux neutron beams.\u003c/p\u003e\u003cp\u003eThe masses of \u003csup\u003e238\u003c/sup\u003eU in the coatings are measured by SSA and GIC respectively. Among them, the energy resolution of SSA is significantly better than that of GIC. The masses of \u003csup\u003e238\u003c/sup\u003eU in the U1 coating measured by the two devices are 0.3348mg and 0.3347mg, respectively, with relative uncertainty of 1.08% and 1.02%. While the masses of \u003csup\u003e238\u003c/sup\u003eU in the U2 coating are 0.3097mg and 0.3129mg, respectively, with relative uncertainty of 1.08% and 1.09%. The normalized standard deviations of the two devices are calculated, and it is found that \u003cem\u003eE\u003c/em\u003e\u003csub\u003e\u003cem\u003en\u003c/em\u003e\u003c/sub\u003e\u0026lt;0.01. Thus, the results obtained by the two devices are consistent within the uncertainties.\u003c/p\u003e"},{"header":"Declarations","content":"\u003ch2\u003eAuthor Contribution\u003c/h2\u003e\u003cp\u003eH.Y.Y. was responsible for the actual operation process of most of the experiments and wrote the main manuscript text. L.Y.N. and L.Y.T. revised and improved the manuscript. C.K.S. prepared Figures 1-3. L.C.J., B.J., and Y.S.H. provided theoretical support and professional guidance. All the authors reviewed the manuscript.\u003c/p\u003e\u003ch2\u003eAcknowledgements\u003c/h2\u003e\u003cp\u003eThere is no Funding in the manuscript.\u003c/p\u003e"},{"header":"References","content":"\u003col\u003e\n\u003cli\u003eInternational Atomic Energy Agency[EB/OL]. https://www.iaea.org/.\u003c/li\u003e\n\u003cli\u003eBurattini, P. , Leonardi, S. , Orlandi, P. , \u0026amp; Antonia, R. A. . (2008). Comparison between experiments and direct numerical simulations in a channel flow with roughness on one wall. Journal of Fluid Mechanics, 600, 403-426. \u003c/li\u003e\n\u003cli\u003eYang, Y. , Wen, Z. , Han, Z. , Wang, M. , Liu, R. , \u0026amp; Wen, J. , et al. (2019). A multi-cell fission chamber for fission cross-section measurements at the back-n white neutron beam of csns. Nuclear Instruments \u0026amp; Methods in Physics Research. Section A, Accelerators, Spectrometers, Detectors and Associated Equipment, 940(OCT.1), 486-491.\u003c/li\u003e\n\u003cli\u003eParadela, C. , Fujii, K. , Vlastou, R. , Furman, W. , Abbondanno, U. , \u0026amp; Duran, I. , et al. (2010). Neutron-induced fission cross section of u-234 and np-237 measured at the cern neutron time-of-flight (n_tof) facility. Physical Review C, 82(3).\u003c/li\u003e\n\u003cli\u003eTarrio, D. , Belloni, F. , Berthoumieux, E. , Chiaveri, E. , \u0026amp; Gunsing, F. . (2014). Measurement of the angular distribution of fission fragments using a ppac assembly at cern n_tof. Nuclear Instruments and Methods in Physics Research, Section A. Accelerators, Spectrometers, Detectors and Associated Equipment, 743, 79-85.\u003c/li\u003e\n\u003cli\u003eKuruc, J. , D\u0026aacute;vid Harvan, Du\u0026scaron;an Galanda, L\u0026rsquo;ubom\u0026iacute;r M\u0026aacute;tel, \u0026amp; Monika Jerigov\u0026aacute;Du\u0026scaron;an Velic. (2011). Alpha spectrometry and secondary ion mass spectrometry of electrodeposited uranium films. Journal of Radioanalytical\u0026amp;Nuclear Chemistry.\u003c/li\u003e\n\u003cli\u003eGEBAUER, \u0026amp; B. (2004). Towards detectors for next generation spallation neutron sources. Nuclear Instruments \u0026amp; Methods in Physics Research, 535(1-2), 65-78.\u003c/li\u003e\n\u003cli\u003eYi, T. , Xing, P. , Li, C. , Xie, J. , \u0026amp; Li, G. . (2009). Progresses in uranium film fabrication and application. Nuclear Techniques, 32(12), 905-910.\u003c/li\u003e\n\u003cli\u003eZhang, L. , Wu, X. , Ding, H. , Fan, F. , Bai, J. , \u0026amp; Lin, M. , et al. (2009). The preparation of 238u targets on 2 \u0026mu;m al foils. North-Holland(20).\u003c/li\u003e\n\u003cli\u003eLiu Shengkang. (1986). Neutron Physics. Atomic Energy Press.\u003c/li\u003e\n\u003cli\u003eO. Bunemann, , T. E. Cranshaw, and , J. A. Harvey. (1949). Design of grid ionization chambers. Instruments \u0026amp; Experimental Techniques, 52(52), 260-264.\u003c/li\u003e\n\u003cli\u003eAgostinelli, S. , Allison, J. , Amako, K. , Apostolakis, J. , \u0026amp; Zschiesche, D. . (2003). Geant4\u0026mdash;a simulation toolkit. Nuclear Instruments and Methods in Physics Research Section A Accelerators Spectrometers Detectors and Associated Equipment, 506(3), 250.\u003c/li\u003e\n\u003c/ol\u003e"}],"fulltextSource":"","fullText":"","funders":[],"hasAdminPriorityOnWorkflow":false,"hasManuscriptDocX":true,"hasOptedInToPreprint":true,"hasPassedJournalQc":"","hasAnyPriority":false,"hideJournal":true,"highlight":"","institution":"","isAcceptedByJournal":false,"isAuthorSuppliedPdf":false,"isDeskRejected":"","isHiddenFromSearch":false,"isInQc":false,"isInWorkflow":false,"isPdf":false,"isPdfUpToDate":true,"isWithdrawnOrRetracted":false,"journal":{"display":true,"email":"[email protected]","identity":"researchsquare","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":true,"externalIdentity":"","sideBox":"","snPcode":"","submissionUrl":"/submission","title":"Research Square","twitterHandle":"researchsquare","acdcEnabled":true,"dfaEnabled":false,"editorialSystem":"","reportingPortfolio":"","inReviewEnabled":false,"inReviewRevisionsEnabled":true},"keywords":"Quantification, Uranium in coatings, Small solid angle device, Grid ionization chamber, Alpha spectrometry","lastPublishedDoi":"10.21203/rs.3.rs-7926956/v1","lastPublishedDoiUrl":"https://doi.org/10.21203/rs.3.rs-7926956/v1","license":{"name":"CC BY 4.0","url":"https://creativecommons.org/licenses/by/4.0/"},"manuscriptAbstract":"\u003cp\u003eFor neutron detectors used in high-flux neutron beams, dense and uniform \u003csup\u003e238\u003c/sup\u003eU coatings are prepared by electrodeposition using natural uranium on 2\u0026micro;m-thick aluminized mylar foils. The mylar foils with a thickness of \u0026micro;m have a certain degree of ductility and a low neutron reaction cross-section, which can effectively reduce interference signals. Accurate Quantification of \u003csup\u003e238\u003c/sup\u003eU coatings is conducted using a specially designed small solid angle device and a grid ionization chamber, respectively. The results show that the weights of \u003csup\u003e238\u003c/sup\u003eU in coatings are 0.335mg and 0.310mg, with relative uncertainty of 1.02%-1.09% and consistent within the uncertainties.\u003c/p\u003e","manuscriptTitle":"Preparation and Accurate Quantification of 238U Coatings on Thin-Backed","msid":"","msnumber":"","nonDraftVersions":[{"code":1,"date":"2025-11-14 05:41:47","doi":"10.21203/rs.3.rs-7926956/v1","editorialEvents":[{"type":"communityComments","content":0}],"status":"published","journal":{"display":true,"email":"[email protected]","identity":"researchsquare","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":true,"externalIdentity":"","sideBox":"","snPcode":"","submissionUrl":"/submission","title":"Research Square","twitterHandle":"researchsquare","acdcEnabled":true,"dfaEnabled":false,"editorialSystem":"","reportingPortfolio":"","inReviewEnabled":false,"inReviewRevisionsEnabled":true}}],"origin":"","ownerIdentity":"ba78d195-271d-4c75-90fd-e6cba6dc1bdf","owner":[],"postedDate":"November 14th, 2025","published":true,"recentEditorialEvents":[],"rejectedJournal":[],"revision":"","amendment":"","status":"posted","subjectAreas":[],"tags":[],"updatedAt":"2025-12-15T15:54:23+00:00","versionOfRecord":[],"versionCreatedAt":"2025-11-14 05:41:47","video":"","vorDoi":"","vorDoiUrl":"","workflowStages":[]},"version":"v1","identity":"rs-7926956","journalConfig":"researchsquare"},"__N_SSP":true},"page":"/article/[identity]/[[...version]]","query":{"redirect":"/article/rs-7926956","identity":"rs-7926956","version":["v1"]},"buildId":"8U1c8b4HqxoKbykW_rLl7","isFallback":false,"isExperimentalCompile":false,"dynamicIds":[84888],"gssp":true,"scriptLoader":[]}