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Activation cross sections of α-particle-induced reactions on natMg were measured. The stacked-foil activation technique combined with high-resolution γ-ray spectrometry was adopted for the measurements. The experiment was conducted at the RIKEN AVF cyclotron. Production cross sections of 28Mg and 24,22Na were experimentally determined for α-particle energies up to 50 MeV.
Production cross sections of 61Cu in alpha-particle-induced reactions on 59Co
α-particle-induced reactions on natFe were studied with a special focus on possible medical radionuclides 58mCo and 55Co. Cross sections for production of 57,56Ni, 58m,58g,57,56,55Co, 52gFe, 56,54,52gMn, and 51Cr and thick target yields of 57,56Ni, 58g,57,56,55Co, and 54,52gMn were determined. Based on agreement between experimental and calculated yields using the measured cross sections, high reliability of the experimental data could be reached. The thick target yields of 58mCo and 55Co were calculated and found to be 36 GBq/C (129 MBq/μAh) and 17 MBq/C (62 kBq/μAh) at 35 MeV, respectively. The yield of 58mCo is promisingly high although that of 55Co is low through the reactions.
Cadmium-109 has a 462-day half-life and decays to 109mAg (T1/2 = 39.79 s), a source of γ rays. This decay process makes 109Cd useful for calibrating radiation detectors, tracking cadmium pollution.1) Moreover, this radionuclide can be considered as a generator of 109mAg, which emits 88.03-keV γ rays suitable for single photon emission computed tomography (SPECT).2) Potential production routes of 109Cd are charged-particle-induced reactions on silver, and palladium targets. Among these production routes, the natAg(α,x)109Cd reaction is considered as promising one.3) However, the experimental data of the natAg(α,x)109Cd reaction are largely scattered. Therefore, this study aims to measure the production cross-sections of ¹⁰⁹Cd via α-particle bombardment of natural silver to investigate production routes.
The radionuclide 189gIr, an Auger electron emitter, is suitable for therapy in nuclear medicine.1) It has three isomeric states: the ground state 189gIr (T1/2 = 13.2 d, ε: 100%) and two short-lived excited states 189m1Ir (T1/2 = 13.3 ms) and 189m2Ir (T1/2 = 3.7 ms), both of which decay to the ground state via isomeric transition (IT: 100%). Possible routes for 189gIr production are p- and d-induced reactions on natOs or enriched 189Os and 188Os targets. Alternative production routes are α-particle-induced reactions on natRe and enriched 187Re targets. In this work, we focused on the α-particle-induced reactions on natRe. Our literature survey found two experimental studies on 189gIr production via α-particle-induced reactions on rhenium.2,3) Their experimental data show significant differences in both peak position and amplitude. Therefore, we measured the excitation functions of α-particle-induced reactions on natRe up to 50 MeV and compared the results with experimental data from past studies and the TENDL-2021 library.
Among positron-emitting isotopes, 118Sb is a potential candidate for Positron Emission Tomography (PET) due to its short half-life (T1/2 = 3.6 min), high positron emission probability (75%), and low intensity of accompanying high-energy γ radiation (Eγ = 1229.33 keV, Iγ = 2.5%). This makes it suitable for use in PET imaging.1) Another advantage of this isotope is that it can be obtained using a 118Te/118Sb generator with the decay of 118Te, which has a half-life of 6 days.2,3) The isotope 118Te can be produced with accelerators by nuclear reactions of light-charged-particles on natural or isotopically enriched tin (Sn) or antimony (Sb).4) Only one experimental study measuring the natSn(α,n)118Te reaction cross section5) was identified in our literature survey, indicating a lack of experimental data and necessity to accurately determine its cross section.
Copper radionuclides can be used in nuclear medicine.1) 64Cu (T1/2 = 12.70 h) and 67Cu (T1/2 = 61.83 h) are employed for single-photon emission computed tomography (SPECT) imaging and β^--particle therapy, respectively. Their combination can be theranostic applications. In addition, 62Cu (T1/2 = 9.672 min) is a positron emitter (I_(β^+ ) = 97.83%) suitable for positron emission tomography (PET), which can be produced via the 62Zn/62Cu generator.2) The parent nucleus, 62Zn (T1/2 = 9.193 h), is synthesized through charged-particle-induced reactions on copper and nickel targets. One such reaction for 62Zn production is the 7Li-induced reaction on natNi. This reaction is also a candidate for a monitor reaction, which we systematically study.3,4) Therefore, we conducted measurements of the cross sections for the reactions.
The production cross sections of the 59Co(α,2n)61Cu reaction were measured at the AVF cyclotron of the RIKEN RI Beam Factory. The stacked-foil activation technique and high-resolution γ-ray spectrometry were adopted to derive the cross sections. The derived cross sections were compared with experimental data studied earlier and with the theoretical calculation in the TENDL library.
The excitation function of the natSn(α,x)118Te reaction was measured up to 50 MeV using the stacked-foil activation technique and high-resolution γ-ray spectrometry. The cross sections of the co-products, 110g,111gIn, 113g,117mSn,116m,117,118m,120m,122g,124g,126gSb, and 116,117g,118,119g,119m,121g,121m,123mTe, were also determined. Based on the measured cross section, the physical thick target yields of 118Te, 119g,mTe, 121g,mTe, and 123mTe were deduced.
The isomeric ratios and cross sections were measured up to 50 MeV for production of 198m,gAu, 197m,gHg,195m,gHg and other Hg, Au and Pt radionuclides in irradiation of natural platinum by alpha-particles using the stacked-foil activation technique and offline gamma-ray spectrometry. The simultaneous decay curve analysis was applied to the emission rates of more than 40 gamma lines to directly derive the independent cross sections of all products without determining the cumulative cross sections. The measured cross sections and isomeric ratios were compared with those compiled in the EXFOR library and simulated by TALYS-2.0. We found that the natPt(α,x)198g+mAu, 197g+mHg and 195g+mHg cross sections are fairly reproduced by the simulation, while the simulation result requires adjustment of the spin cutoff parameter for better reproduction of the isomeric ratios.
Энэхүү судалгаа нь толгой, хүзүүний хорт хавдрын туяа эмчилгээнд шинээр нэвтрүүлсэн Эрчмийг тохируулах туяа эмчилгээ (ЭТТЭ)-нийтехнологийн үр нөлөөг үнэлэх зорилготой. Судалгаанд 2022-2023 онд ЭТТЭ эмчилгээ хийлгэсэн 10 өвчтөн оролцсон бөгөөд 3 хэмжээст конформал туяа эмчилгээ (3Х КТЭ)-тэй харьцуулан дозиметр, радиобиологийн үр дүнг судалсан. PTV-ийн тохиромжийн индекс (CI) болонжигд тархалтын индекс (HI) нь ЭТТЭ аргаар илүү өндөр гарсан. PTV70-ийн дундаж тун 3Х КТЭ-д 101%, ЭТТЭ-д 100% байв. OARs-ийн хамгаалалтын хувьд ЭТТЭ нь тунгийн өртөлтийг бууруулж, ялангуяа шүлсний булчирхайн дундаж тунг 3Х КТЭ-ээс 43%-иар багасгасан (51.61Гр → 29.09 Гр). ЭТТЭ төлөвлөлт нь PTV-д 70 Гр тун өгөх үед 3Х КТЭ-ээс 4 Гр-ээр өндөр тун түгээж, шаардлагыг илүү хангаж байв. Судалгааны дүнд ЭТТЭ технологи нь хавдрын талбайн тунгийн тархалтыг сайжруулж, эрүүл эдийг хамгаалахад үр дүнтэй болохыг тогтоосон.
Бид энэхүү судалгааны ажлаар118Te/118Sb генераторынэх изотопболох118Tе-ийг natSn(α,x)118Teгарган авахцөмийн урвалын огтлолыг хэмжлээ. Урвалын огтлолыг тодорхойлох туршилтад цэнэгт бөөмөөр идэвхжүүлэхаргахэрэглэнγ-спектрометрыг хэмжилтэд ашиглав.118Tе-ийн физик гаралтыг туршилтаас тодорхойлсон урвалын огтлолоос үнэлсэн.Энэхүү ажлаар 40 Мэв хүртэл хурдассан альфа бөөмөөр явагдах natSn(α,x)118Te урвалын огтлолыг хэмжсэн үр дүн нь бусад судлаачдын үр дүнтэй нийцтэй байв. Түүнчлэн 40-50 МэВ энергийн мужидnatSn(α,x)118Te урвалын огтлолыг шинэ утгуудыг хэмжиж тодорхойлов.
Activation cross sections of alpha-particle-induced reactions on natural rhenium were measured. The stacked-foil activation technique and high-resolution gamma-ray spectrometry were used to derive the cross sections. The production cross sections of 190g, 189g, 188g, 187g, 186g, 185, 184Ir, 185Os, and 184g, 183gRe were determined up to 50 MeV. The cross sections of 185, 184Ir were measured for the first time. The experimental results were compared with previous experimental data and theoretical calculations in the TENDL-2021 library.
Activation cross sections of proton-induced reactions on natural platinum were measured. The stacked-foil activation technique and high-resolution gamma-ray spectrometry were used. The production cross sections of 198, 196, 196m2, 195, 194, 193, 192, 191Au, 191Pt, and 192, 190Ir were determined up to 30 MeV. The experimental results were compared with previous experimental data and theoretical calculations in the TENDL-2019 library.
Gold-198 has tow long-lived states, the ground state 198gAu (T1/2=2.6941 d, ϐ-: 100%) and the excited state 198mAu (T1/2=2.272 d, IT: 100%). The ground state can be used in nuclear medicine, such as brachytherapy1) and nanoparticles.2) The neutron capture 197Au reaction on the monoisotopic element 197Au in a reactor can produce a considerable amount of 198gAu. However, this method yields only the low specific activity of 198gAu owing to the difficulty encountered in separating 198gAu from the Au target.
Manganese-52 has the long-lived ground state 52gMn (T1/2 = 5.6 d, ε +ϐ+ : 100%) and the shorter-lived excited state 52mMn (T1/2 = 21.1 min, IT: 1.78%, ε +ϐ+ : 98.22%). The decay processes of 52gMn are electron capture (70.6%) and positron emission (29.4%, 〈E_(ϐ+) 〉=242 keV). The positrons emitted from the decay of 52gMn can be used for Positron Emission Tomography (PET) The direct routes to produce 52gMn involve charged-particle-induced reaction on chromium and vanadium. Whereas, the indirect route involves the internal transition of 52mMn co-produced simultaneously in the reactions.
Activation cross sections of alpha-particle-induced reactions on natural vanadium were measured. The production cross sections of 54, 52gMn, 51Cr, 48V, and 47, 46gSc were determined up to 50 MeV. The stacked-foil activation technique and high-resolution gamma-ray spectrometry were used. The experimental results were compared with previous experimental data and theoretical calculations in the TENDL-2019 library. The physical yield of the medical radionuclide 52gMn was derived from the measured cross sections.
Excitation functions for α-induced reactions on natural vanadium were calculated in the energy range up to 50 MeV. The production cross sections of 52Mn will be compared to some previously published results and the TALYS (TENDL 2019) code calculations. The integral yield of 52Mn is derived from the calculated cross-sections and compared with those from other production routes.
Монгол улс анхны цөмийн судалгааны реакторыг эмнэлгийн зориулалттай цацраг идэвхт изотоп үйлдвэрлэх, шаардлагатай хүний нөөцөө бэлтгэх зориулалттай ашиглахаар төлөвлөж байна. Уг судалгааны реакторын техникийн үзүүлэлт ямар байх асуудал дээр эрдэмтэн судлаачид болон шийдвэр гаргагчид нэгдсэн шийдвэрт хүрээгүй байна. Эрдэмтдийн зүгээс чадлын хувьд дунд төвшний реактор манай улсад илүү тохиромжтой гэсэн өнцгөөс харж байгаа бол шийдвэр гаргагчдын хувьд реакторын үнэ ханш өндөр үнэтэй болно гэсэн байр суурьтай байдаг. Энэхүү судалгааны ажлаар реакторын техникийн үзүүлэлтийг харьцуулсан гурван өөр түлш бүхий, чадлын хувьд ялгаатай судалгааны реакторуудын дизайны судалгааг хийж, реакторын чадлаас хамаарч судалгааны реакторын хэрэглээ, ашиглалт хэрхэн өөрчлөгдөж болохыг харуулахыг зорьсон.
Импортын болон дотоодын зарим хүнсний ногоо (чинжүү, сонгино, сармис)-ын дээжид рентген-флуоресценцийн болон идэвхжилийн шинжилгээний аргаар макро, микро элементийн агуулгыг тодорхойлж, үр дүнг олон улсын болон монгол улсын стандарт (зөвшөөрөгдөх) утгатай харьцуулан үнэлсэн талаар өгүүлнэ. Энэ ажлыг “Хүрээлэн буй орчин, биологийн объектыг шинжлэх цөмийн физикийн аргазүйн судалгаа” сэдэвт ажлын хүрээнд хийж гүйцэтгэв.
Fluorite is one of the important strategic resources, it is included in the secret material list in some countries depending on the industrial application. Mongolia is ranging in third place in the world for mining of fluorite after China and Mexico and in second place for export of fluorite after Mexico. Fluorite has many applications such as the production of welding electrode, cement, and glass for optics, an artificial organ such as artificial heart and transferring blood in medical use; to produce cryolite solution for aluminum by the electrolyzing method; uranium enrichment in nuclear technology and etc. For determination of fluorite content widely used chemical and neutron activation analysis. But these are expensive and required a long time. In this work, an indirect method using XRF analysis for determination of fluorite content in fluorite ore is described.
Fluorite is one of the important strategic resources, it is included in the secret material list in some countries depending on the industrial application. Mongolia is ranging in third place in the world for mining of fluorite after China and Mexico and in second place for export of fluorite after Mexico. Fluorite has many applications such as the production of welding electrode, cement, and glass for optics, an artificial organ such as artificial heart and transferring blood in medical use; to produce cryolite solution for aluminum by the electrolyzing method; uranium enrichment in nuclear technology and etc. For determination of fluorite content widely used chemical and neutron activation analysis. But these are expensive and required a long time. In this work, an indirect method using XRF analysis for determination of fluorite content in fluorite ore is described.
Certified Reference Material (CRM) is an important role in quality control of the tests, calibration of equipment and instruments, method validation and traceability. In this work, some chemical elements determined using the XRF method in a sample of coal fly ash prepared by the Central Geological Laboratory for the CRM at Nuclear Research Center (NRC) of the National University of Mongolia (NUM).
