{"id":345,"date":"2026-05-13T09:50:56","date_gmt":"2026-05-13T09:50:56","guid":{"rendered":"https:\/\/ntlab.hcmus.edu.vn\/?page_id=345"},"modified":"2026-05-14T07:38:35","modified_gmt":"2026-05-14T07:38:35","slug":"ban-tin-khoa-hoc","status":"publish","type":"page","link":"https:\/\/ntlab.hcmus.edu.vn\/?page_id=345","title":{"rendered":"B\u1ea2N TIN KHOA H\u1eccC"},"content":{"rendered":"\n<div class=\"ntlab-scientific-news\">\n\n  <style>\n    .ntlab-scientific-news {\n      max-width:1050px;\n      margin:0 auto;\n      padding:28px;\n      background:#ffffff;\n      color:#222222;\n      font-family:Arial, sans-serif;\n      font-size:16px;\n      line-height:1.65;\n    }\n\n    .ntlab-news-header {\n      text-align:center;\n      margin-bottom:32px;\n    }\n\n    .ntlab-lab-name {\n      font-size:15px;\n      color:#555555;\n      margin-bottom:8px;\n    }\n\n    .ntlab-page-title {\n      font-size:30px;\n      font-weight:700;\n      color:#00549f;\n      letter-spacing:0.5px;\n      margin-bottom:10px;\n    }\n\n    .ntlab-page-desc {\n      font-size:17px;\n      color:#444444;\n      max-width:760px;\n      margin:0 auto;\n    }\n\n    .ntlab-article-card {\n      border:1px solid #d9e4ef;\n      border-radius:8px;\n      padding:24px;\n      margin-bottom:26px;\n      background:#f9fcff;\n      box-shadow:0 2px 8px rgba(0,0,0,0.04);\n    }\n\n    .ntlab-article-label {\n      display:inline-block;\n      background:#00549f;\n      color:#ffffff;\n      padding:5px 12px;\n      border-radius:4px;\n      font-size:14px;\n      font-weight:600;\n      margin-bottom:14px;\n    }\n\n    .ntlab-article-title {\n      font-size:22px;\n      font-weight:700;\n      line-height:1.45;\n      margin-bottom:14px;\n    }\n\n    .ntlab-article-title a {\n      color:#003f7d;\n      text-decoration:none;\n    }\n\n    .ntlab-article-title a:hover {\n      color:#00549f;\n      text-decoration:underline;\n    }\n\n    .ntlab-info-box {\n      background:#ffffff;\n      border-left:4px solid #00549f;\n      padding:14px 18px;\n      margin-bottom:18px;\n    }\n\n    .ntlab-info-row {\n      margin-bottom:8px;\n    }\n\n    .ntlab-info-label {\n      font-weight:600;\n      color:#333333;\n    }\n\n    .ntlab-section-title {\n      font-size:18px;\n      font-weight:700;\n      color:#00549f;\n      margin-bottom:10px;\n    }\n\n    .ntlab-abstract {\n      text-align:justify;\n    }\n\n    .ntlab-pagination {\n      display:flex;\n      justify-content:center;\n      align-items:center;\n      gap:12px;\n      margin-top:30px;\n      padding-top:10px;\n    }\n\n    .ntlab-page-button {\n      background:#00549f;\n      color:#ffffff;\n      border:none;\n      border-radius:5px;\n      padding:9px 18px;\n      font-size:15px;\n      cursor:pointer;\n      font-family:Arial, sans-serif;\n    }\n\n    .ntlab-page-button:hover {\n      background:#003f7d;\n    }\n\n    .ntlab-page-button:disabled {\n      background:#cccccc;\n      color:#666666;\n      cursor:not-allowed;\n    }\n\n    .ntlab-page-info {\n      font-size:15px;\n      color:#333333;\n      min-width:90px;\n      text-align:center;\n    }\n\n    @media screen and (max-width:700px) {\n      .ntlab-scientific-news {\n        padding:18px;\n      }\n\n      .ntlab-page-title {\n        font-size:25px;\n      }\n\n      .ntlab-article-title {\n        font-size:19px;\n      }\n\n      .ntlab-article-card {\n        padding:18px;\n      }\n\n      .ntlab-pagination {\n        gap:8px;\n      }\n\n      .ntlab-page-button {\n        padding:8px 12px;\n        font-size:14px;\n      }\n    }\n  <\/style>\n\n\n  <div class=\"ntlab-news-header\">\n    <div class=\"ntlab-lab-name\">\n      Ph\u00f2ng th\u00ed nghi\u1ec7m K\u1ef9 thu\u1eadt H\u1ea1t nh\u00e2n\n    <\/div>\n\n    <div class=\"ntlab-page-title\">\n      B\u1ea2N TIN KHOA H\u1eccC\n    <\/div>\n  <\/div>\n\n\n  <div id=\"ntlabArticleList\">\n\n    <div class=\"ntlab-article-card\">\n\n      <div class=\"ntlab-article-label\">B\u00e0i b\u00e1o<\/div>\n\n      <div class=\"ntlab-article-title\">\n        <a href=\"https:\/\/link.springer.com\/article\/10.1007\/s10967-026-10917-w\" target=\"_blank\" rel=\"noopener noreferrer\">\n          Processes controlling the activity concentrations of naturally occurring radionuclides in the water spinach (<i>Ipomoea aquatica<\/i>) soil: experimental and modelling studies\n        <\/a>\n      <\/div>\n\n      <div class=\"ntlab-info-box\">\n        <div class=\"ntlab-info-row\">\n          <span class=\"ntlab-info-label\">T\u00e1c gi\u1ea3:<\/span>\n          Van Thang Nguyen, Thanh Ngan Quach, Cao Minh Quan Le, Xuan Anh Dao Lam, Ngoc Ba Vu &amp; Cong Hao Le\n        <\/div>\n\n        <div>\n          <span class=\"ntlab-info-label\">T\u1ea1p ch\u00ed:<\/span>\n          Journal of Radioanalytical and Nuclear Chemistry\n        <\/div>\n      <\/div>\n\n      <div class=\"ntlab-section-title\">\n        T\u00f3m t\u1eaft\n      <\/div>\n\n      <div class=\"ntlab-abstract\">\n        This study investigated the mitigation of naturally occurring radionuclides (NORs) in cultivated soil. Processes of vertical leaching and plant uptake were considered. A laboratory experiment was conducted on water spinach (<i>Ipomoea aquatica<\/i>) soils. The average solid\u2013liquid partition coefficients (K<sub>d<\/sub>) of <sup>238<\/sup>U (K<sub>dU<\/sub>), <sup>226<\/sup>Ra (K<sub>dRa<\/sub>), and <sup>210<\/sup>Po (K<sub>dPo<\/sub>) are 4815, 3354 and 2379 L kg<sup>\u22121<\/sup>, respectively. The average soil-to-plant transfer factor (TF) of gross alpha (TF<sub>alpha<\/sub>), <sup>238<\/sup>U (TF<sub>U<\/sub>), <sup>226<\/sup>Ra (TF<sub>Ra<\/sub>) and <sup>210<\/sup>Po (TF<sub>Po<\/sub>) are 0.048, 0.068, 0.099 and 0.164, respectively. Both K<sub>d<\/sub> and TF of the radionuclides correlate with the soil organic matter (OM) content. For long-lived radionuclides (e.g., <sup>238<\/sup>U and <sup>226<\/sup>Ra), vertical leaching in soil and transfer to plants are major processes. In contrast, for short-lived radionuclides (e.g., <sup>210<\/sup>Po), the radioactive decay is more important.\n      <\/div>\n\n    <\/div>\n\n\n    <div class=\"ntlab-article-card\">\n\n      <div class=\"ntlab-article-label\">B\u00e0i b\u00e1o<\/div>\n\n      <div class=\"ntlab-article-title\">\n        <a href=\"https:\/\/www.sciencedirect.com\/science\/article\/pii\/S0168900226002706?via%3Dihub\" target=\"_blank\" rel=\"noopener noreferrer\">\n          Background subtraction using the SNIP method enhanced by the Levenberg\u2013Marquardt algorithm\n        <\/a>\n      <\/div>\n\n      <div class=\"ntlab-info-box\">\n        <div class=\"ntlab-info-row\">\n          <span class=\"ntlab-info-label\">T\u00e1c gi\u1ea3:<\/span>\n          Le Anh Nhi, Chau Thanh Tai, Vu Ngoc Ba, Tran Thien Thanh, Le Cong Hao, Chau Van Tao\n        <\/div>\n\n        <div>\n          <span class=\"ntlab-info-label\">T\u1ea1p ch\u00ed:<\/span>\n          Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated Equipment\n        <\/div>\n      <\/div>\n\n      <div class=\"ntlab-section-title\">\n        T\u00f3m t\u1eaft\n      <\/div>\n\n      <div class=\"ntlab-abstract\">\n        In this study, a practical refinement of the SNIP method is proposed for background subtraction in HPGe \u03b3-ray spectra. A single filter width determined from the detector specifications is used in Gaussian convolution to obtain preliminary peak parameters, which are then refined using the Levenberg\u2013Marquardt (LM) algorithm to provide more reliable peak widths for SNIP background subtraction. The resulting method, referred to as LMSNIP, is evaluated using the <sup>154<\/sup>Eu spectra measured at 25 cm and 5 cm. The reconstructed backgrounds are directly compared with those obtained using the adaptive SNIP approach, while the resulting net peak areas are compared with Genie2K. For the 25 cm spectrum, LMSNIP and adaptive SNIP provide generally similar background estimates. Under the more demanding 5 cm condition, however, LMSNIP yields a smoother and more stable baseline and generally better agreement with Genie2K for most investigated peaks. Additional validation using the <sup>133<\/sup>Ba spectrum measured at 5 cm further shows that LMSNIP remains effective for a reference spectrum with different low-energy characteristics. These results support the applicability of LMSNIP to background reconstruction and net peak-area determination under the investigated close-geometry conditions.\n      <\/div>\n\n    <\/div>\n\n\n    <div class=\"ntlab-article-card\">\n\n      <div class=\"ntlab-article-label\">B\u00e0i b\u00e1o<\/div>\n\n      <div class=\"ntlab-article-title\">\n        <a href=\"https:\/\/link.springer.com\/article\/10.1007\/s10967-026-10839-7\" target=\"_blank\" rel=\"noopener noreferrer\">\n          Feature, transfer and radiological risk assessment of natural radionuclides from soil to plants at high background radiation area: a case study ambient of the rare earth mine, Muong Hum, Northern Vietnam\n        <\/a>\n      <\/div>\n\n      <div class=\"ntlab-info-box\">\n        <div class=\"ntlab-info-row\">\n          <span class=\"ntlab-info-label\">T\u00e1c gi\u1ea3:<\/span>\n          Van-Loat Bui, Van-Hao Duong, Thi Hong Bui, Duc-Thang Duong, Vu Ngoc Ba, Anh-Hung Vu, Viet-Hoang Tran, Thi Mai Pham, Somsavath Leuangtakoun, Hue Nguyen Thanh Kim\n        <\/div>\n\n        <div>\n          <span class=\"ntlab-info-label\">T\u1ea1p ch\u00ed:<\/span>\n          Journal of Radioanalytical and Nuclear Chemistry\n        <\/div>\n      <\/div>\n\n      <div class=\"ntlab-section-title\">\n        T\u00f3m t\u1eaft\n      <\/div>\n\n      <div class=\"ntlab-abstract\">\n        This study investigates natural radionuclide contamination in soils and edible plants from the high-background radiation area of Muong Hum, Northern Vietnam. <sup>226<\/sup>Ra, <sup>228<\/sup>Ra, and <sup>40<\/sup>K activity concentrations in both soils and plants were significantly elevated, with strong species-dependent differences reflecting distinct physiological uptake mechanisms and the predominance of thorium-series isotopes. Total annual effective doses reached 0.46\u20133.15 mSv y<sup>\u22121<\/sup> and 35.29% of sites exceeded the 1 mSv y<sup>\u22121<\/sup>. These results indicate that elevated environmental baselines, rather than transfer factors alone, drive total exposure. Further monitoring, species-specific risk assessments, and targeted management strategies are recommended to safeguard food safety and public health.\n      <\/div>\n\n    <\/div>\n\n\n    <div class=\"ntlab-article-card\">\n\n      <div class=\"ntlab-article-label\">B\u00e0i b\u00e1o<\/div>\n\n      <div class=\"ntlab-article-title\">\n        <a href=\"https:\/\/link.springer.com\/article\/10.1007\/s12648-026-03966-0\" target=\"_blank\" rel=\"noopener noreferrer\">\n          Study on the influence of targets on spectral response in different regions using MCNP6\n        <\/a>\n      <\/div>\n\n      <div class=\"ntlab-info-box\">\n        <div class=\"ntlab-info-row\">\n          <span class=\"ntlab-info-label\">T\u00e1c gi\u1ea3:<\/span>\n          Huynh Van Tran Sang, Vu Ngoc Ba, Nguyen Ba Doan Trinh, Huynh Truc Van, Phan Thi Xuan Mai, Nguyen Quang Dao, Tran Trung Nguyen, Truong Thi Hong Loan\n        <\/div>\n\n        <div>\n          <span class=\"ntlab-info-label\">T\u1ea1p ch\u00ed:<\/span>\n          Indian Journal of Physics\n        <\/div>\n      <\/div>\n\n      <div class=\"ntlab-section-title\">\n        T\u00f3m t\u1eaft\n      <\/div>\n\n      <div class=\"ntlab-abstract\">\n        This study utilizes a NaI detector and MCNP6 simulations to evaluate the influence of target characteristics on gamma-ray spectral distributions. Results indicate that increasing the aluminum target thickness from 0 to 3 cm, the valley and Compton regions rose by up to 3.14 times at 383 keV, while the photoelectric peak declined by 0.67 times at 1332 keV. Furthermore, a Compton scattering peak at a 120\u00b0 angle was identified at 383 keV within lead shielding. Notably, as lead thickness increased from 1.0 to 4.0 cm, peak 1 efficiency (Compton scattering peak) dropped 26 times, while peak 2 efficiency (photoelectric peak) decreased over 2514 times. Similarly, increasing target density from 10 to 14.5 g\/cm<sup>3<\/sup> reduced peak 1 by only 23% but peak 2 by over 96%. Additionally, increasing the target-to-detector distance diminished the Compton region, a phenomenon attributed to the build-up effect. These findings underscore the importance of shielding properties in industrial and medical applications.\n      <\/div>\n\n    <\/div>\n\n\n    <div class=\"ntlab-article-card\">\n\n      <div class=\"ntlab-article-label\">B\u00e0i b\u00e1o<\/div>\n\n      <div class=\"ntlab-article-title\">\n        <a href=\"https:\/\/www.sciencedirect.com\/science\/article\/pii\/S1738573326000318?via%3Dihub\" target=\"_blank\" rel=\"noopener noreferrer\">\n          Impact of Non-Uniform Dead Layer Distribution on Efficiency Calibration for Volumetric Sources in HPGe Detectors\n        <\/a>\n      <\/div>\n\n      <div class=\"ntlab-info-box\">\n        <div class=\"ntlab-info-row\">\n          <span class=\"ntlab-info-label\">T\u00e1c gi\u1ea3:<\/span>\n          Huynh Thi Yen Hong, Truong Huu Ngan Thy, Vu Ngoc Ba\n        <\/div>\n\n        <div>\n          <span class=\"ntlab-info-label\">T\u1ea1p ch\u00ed:<\/span>\n          VNUHCM Journal of Science and Technology Development\n        <\/div>\n      <\/div>\n\n      <div class=\"ntlab-section-title\">\n        T\u00f3m t\u1eaft\n      <\/div>\n\n      <div class=\"ntlab-abstract\">\n        Accurate characterization of the HPGe detector dead layer is crucial for reliable Monte Carlo simulations in gamma-ray spectrometry. This study investigates the impact of source geometry on the determination of the effective dead layer thickness. Experimental measurements and MCNP6 simulations were conducted using a p-type coaxial HPGe detector with three geometries: a cylindrical source (S1), a 3\u03c0 source (S2), and a Marinelli beaker (S3). Results show that while the physical dead layer distribution is intrinsic to the crystal, the determined effective dead layer parameter is strongly dependent on the irradiation geometry. The on-axis source (S1) indicated a stable frontal dead layer of approximately 0.60 mm. Conversely, volumetric sources (S2 and S3) revealed a thicker lateral dead layer (\u223c1.10\u20131.21 mm) with a significant transition zone at low energies due to the geometric weighting of photon interactions. Crucially, the study demonstrates that applying a uniform dead layer thickness derived from point-source calibration (S1) to volumetric geometries (S3) results in a systematic overestimation of efficiency across the energy range. These findings highlight the inadequacy of uniform dead layer models for complex geometries and the necessity of multi-region characterization for high-accuracy environmental monitoring.\n      <\/div>\n\n    <\/div>\n\n\n    <div class=\"ntlab-article-card\">\n\n      <div class=\"ntlab-article-label\">B\u00e0i b\u00e1o<\/div>\n\n      <div class=\"ntlab-article-title\">\n        <a href=\"https:\/\/journal.hcmue.edu.vn\/index.php\/hcmuejos\/article\/view\/5093\" target=\"_blank\" rel=\"noopener noreferrer\">\n          X\u00e2y d\u1ef1ng m\u00f4 h\u00ecnh m\u1ea1ng n\u01a1-ron nh\u00e2n t\u1ea1o \u0111\u1ec3 x\u00e1c \u0111\u1ecbnh nhanh n\u1ed3ng \u0111\u1ed9 dung d\u1ecbch NaOH d\u1ef1a tr\u00ean ph\u1ed5 truy\u1ec1n qua c\u1ee7a ch\u00f9m tia gamma n\u0103ng l\u01b0\u1ee3ng th\u1ea5p 59,54 keV\n        <\/a>\n      <\/div>\n\n      <div class=\"ntlab-info-box\">\n        <div class=\"ntlab-info-row\">\n          <span class=\"ntlab-info-label\">T\u00e1c gi\u1ea3:<\/span>\n          Nguyen Thanh Dat, Tran Vu Thien An, Vo Diep Trung Tin, Tran Trung Nguyen, Huynh Dinh Chuong, Hoang Thi Kieu Trang, Hoang Duc Tam\n        <\/div>\n\n        <div>\n          <span class=\"ntlab-info-label\">T\u1ea1p ch\u00ed:<\/span>\n          T\u1ea1p ch\u00ed Khoa h\u1ecdc Tr\u01b0\u1eddng \u0110\u1ea1i h\u1ecdc S\u01b0 ph\u1ea1m TP. H\u1ed3 Ch\u00ed Minh\n        <\/div>\n      <\/div>\n\n      <div class=\"ntlab-section-title\">\n        T\u00f3m t\u1eaft\n      <\/div>\n\n      <div class=\"ntlab-abstract\">\n        This study proposes a new approach for rapidly determining the concentration of NaOH solutions by measuring the attenuation of a low-energy 59.54 keV \u03b3-ray beam emitted from a <sup>241<\/sup>Am source and using an artificial neural network (ANN) trained directly on raw spectra. First, Monte Carlo simulations configured are used to generate spectral data. Then these spectral data are directly extracted to train and optimize an ANN model. The predictive performance of the optimized network is benchmarked against a conventional calibration curve that relates the transmission ratio (ln R) between water and NaOH solutions to their concentrations. The obtained results show that the ANN model achieves an average deviation of less than 2.8% from reference concentrations across the tested range, whereas the calibration curve yields deviations above 6.0%. In the low-concentration region (C = 5.0%), the ANN achieves a 2.5% deviation, markedly better than the approximately 12.6% deviation of the calibration curve. The findings suggest that integrating low-energy \u03b3-ray transmission measurements with an ANN model offers a promising methodology for high-precision monitoring of alkaline solutions.\n      <\/div>\n\n    <\/div>\n\n  <\/div>\n\n\n  <div class=\"ntlab-pagination\">\n    <button class=\"ntlab-page-button\" id=\"ntlabPrevBtn\" type=\"button\">Previous<\/button>\n    <span class=\"ntlab-page-info\" id=\"ntlabPageInfo\">Page 1 \/ 1<\/span>\n    <button class=\"ntlab-page-button\" id=\"ntlabNextBtn\" type=\"button\">Next<\/button>\n  <\/div>\n\n\n  <script>\n    document.addEventListener(\"DOMContentLoaded\", function () {\n      var articles = document.querySelectorAll(\".ntlab-scientific-news .ntlab-article-card\");\n      var prevBtn = document.getElementById(\"ntlabPrevBtn\");\n      var nextBtn = document.getElementById(\"ntlabNextBtn\");\n      var pageInfo = document.getElementById(\"ntlabPageInfo\");\n\n      var articlesPerPage = 5;\n      var currentPage = 1;\n      var totalPages = Math.ceil(articles.length \/ articlesPerPage);\n\n      function showPage(page) {\n        currentPage = page;\n\n        articles.forEach(function (article, index) {\n          var start = (currentPage - 1) * articlesPerPage;\n          var end = start + articlesPerPage;\n\n          if (index >= start && index < end) {\n            article.style.display = \"block\";\n          } else {\n            article.style.display = \"none\";\n          }\n        });\n\n        pageInfo.textContent = \"Page \" + currentPage + \" \/ \" + totalPages;\n        prevBtn.disabled = currentPage === 1;\n        nextBtn.disabled = currentPage === totalPages;\n\n        window.scrollTo({\n          top: document.querySelector(\".ntlab-scientific-news\").offsetTop,\n          behavior: \"smooth\"\n        });\n      }\n\n      prevBtn.addEventListener(\"click\", function () {\n        if (currentPage > 1) {\n          showPage(currentPage - 1);\n        }\n      });\n\n      nextBtn.addEventListener(\"click\", function () {\n        if (currentPage < totalPages) {\n          showPage(currentPage + 1);\n        }\n      });\n\n      showPage(1);\n    });\n  <\/script>\n\n<\/div>\n","protected":false},"excerpt":{"rendered":"<p>Ph\u00f2ng th\u00ed nghi\u1ec7m K\u1ef9 thu\u1eadt H\u1ea1t nh\u00e2n B\u1ea2N TIN KHOA H\u1eccC B\u00e0i b\u00e1o Processes controlling the activity concentrations of naturally occurring radionuclides in the water spinach (Ipomoea aquatica) soil: experimental and modelling studies T\u00e1c gi\u1ea3: Van Thang Nguyen, Thanh Ngan Quach, Cao Minh Quan Le, Xuan Anh Dao Lam, Ngoc Ba Vu &amp; Cong Hao [&hellip;]<\/p>\n","protected":false},"author":1,"featured_media":0,"parent":0,"menu_order":0,"comment_status":"closed","ping_status":"closed","template":"","meta":{"footnotes":""},"class_list":["post-345","page","type-page","status-publish","hentry"],"_links":{"self":[{"href":"https:\/\/ntlab.hcmus.edu.vn\/index.php?rest_route=\/wp\/v2\/pages\/345","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/ntlab.hcmus.edu.vn\/index.php?rest_route=\/wp\/v2\/pages"}],"about":[{"href":"https:\/\/ntlab.hcmus.edu.vn\/index.php?rest_route=\/wp\/v2\/types\/page"}],"author":[{"embeddable":true,"href":"https:\/\/ntlab.hcmus.edu.vn\/index.php?rest_route=\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/ntlab.hcmus.edu.vn\/index.php?rest_route=%2Fwp%2Fv2%2Fcomments&post=345"}],"version-history":[{"count":1,"href":"https:\/\/ntlab.hcmus.edu.vn\/index.php?rest_route=\/wp\/v2\/pages\/345\/revisions"}],"predecessor-version":[{"id":349,"href":"https:\/\/ntlab.hcmus.edu.vn\/index.php?rest_route=\/wp\/v2\/pages\/345\/revisions\/349"}],"wp:attachment":[{"href":"https:\/\/ntlab.hcmus.edu.vn\/index.php?rest_route=%2Fwp%2Fv2%2Fmedia&parent=345"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}