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1.
The therapeutic radionuclide 47Sc was produced through the 48Ca(p,2n) channel on a proton beam accelerator. The obtained results show that the optimum proton energies are in the range of 24–17 MeV, giving the possibility to produce 47Sc radionuclide containing 7.4% of 48Sc. After activation, the powdery CaCO3 target material was dissolved in HCl and scandium isotopes were isolated from the targets. The performed separation experiments indicate that, due to the simplicity of the operations and the chemical purity of the obtained 47Sc the best separation process is when scandium radioisotopes are separated on the 0.2 µm filter.  相似文献   

2.
The Nitinol stent was bombarded in a cyclotron at a flux rate of 4 μA/cm2 to produce 48V via 48Ti (p, n) 48V reaction. In this study dose distribution of 48V radioactive stent was investigated for renal arteries. Version X-2.6 of the MCNP Monte Carlo radiation transport system code was employed to calculate dose distribution around the stent. As 48V is a mixed gamma and beta particle emitter, two separate runs of MCNP for both beta and gamma particles were performed and the total deposited dose was acquired by adding the two mentioned values. In order to verify the simulation, the calculated results have been compared with previous published data for the source. Calculated results show high dose gradient near the stent and the maximum amount of dose deposits at the vessel wall. According to (AAPM) TG-60/149 protocol, the dosimetric parameters, including geometry function, G(ρ,z), radial dose function, g L (ρ), and anisotropy function, F(ρ,z), were also determined.  相似文献   

3.
Summary Germanium-68 (270.8 d, EC 100%) is the parent nuclide of 68Ga, a β+ emitter important to positron emission tomography (PET). 68Ge is obtained by a (p,x) induced nuclear reaction on natural Ga. A typical Ga target assembly consists of liquid Ga contained in a Nb capsule, since Nb is one of the few metals resistant to liquid Ga. Zirconium-88 (83.4 d, via 93Nb(p, α2n)) is one longer-lived radioisotope generated by the proton irradiation of naturally mono-isotopic 93Nb. It decays into 88Y, which, in turn, has been considered a useful radiolabel surrogate for 90Y in the investigation of radiolabeled compounds for cancer radioimmunotherapy. This paper introduces a wet chemical procedure for the processing of Nb/Ga target capsules and the simultaneous recovery of 68Ge and 88Zr.  相似文献   

4.
Summary The decay of 101Tc to 101Ru has been studied using high resulation HpGe detectors in single and coincidence mode. Technetium-101 was produced via the 98Mo(α,p)101Tc reaction. The results of the present experiment verified the previously reported levels of 101Ru, but in addition to the known transitions and levels, the 174.91, 226.02, 312.40, 408.77, and 417.91 keV gamma-rays were observed for the first time and they were placed in the decay scheme. At the same time, the transition position of 616.3 keV gamma-ray has been assigned. For most levels the intensities of β--decay and the values of log ft were calculated.  相似文献   

5.
The new complexes [(η3-Me2CCMeCH2)Pd{η2-Ph2P(S)CHP(S)Ph2] (1), [(η3-Me2CCMeCH2)Pd{η2-OC(CF3) CHCO(C4H3S)}] (2) and [(η3-CH2CMeCH2)Pd{η2-OC(CF3)CHCO(C4H3S)}] (3) have been synthesized by reacting [(η3-allyl)Pd(μ-Cl)]2 with Ph2P(S)CH2P(S)Ph2 and OC(CF3)CH2CO(C4H3S) in the presence of base. All have been characterized by elemental analysis, FT-IR, 1H-n.m.r and FAB-mass spectroscopy. Spectroscopic studies suggest that both ligands are bidentate, forming six-membered Pd-S-P-C-P-S and Pd-O-C-C-C-O palladacycles, the η3-allyl group completing the coordination sphere.  相似文献   

6.
In the present study, ytterbium-169 was produced via the 169Tm(p, n)169Yb nuclear process at the AMIRS (Cyclone-30, IBA, Belgium) cyclotron, irradiating Tm2O3 with proton particles of 15 MeV primary energy and 20 μA current for 20 min. Deposition of Tm2O3 on Cu substrate was carried out via by the sedimentation method. The 543 mg of thulium(III)oxide with 108 mg of ethyl cellulose and 8 mL of acetone were used to prepare a Tm2O3 layer of 11.69 cm2. Yields of about 0.643 MBq 169Yb per μAh were experimentally obtained. 169Yb was separated in 80 ± 5% radiochemical yield using liquid–liquid extraction. Solvent extraction of no-carrier-added 169Yb from irradiated thulium(III)oxide target hydrochloric solution was investigated using di-(2-ethylhexyl)phosphoric acid (HDEHP).  相似文献   

7.
Summary Gallium-66 (T1/2 = 9.49 h) is an interesting radionuclide that has potential use for positron emission tomography (PET) imaging of biological processes in intermediate to slow target tissue uptake. 66Ga was produced in the NRCAM cyclotron as a result of 15 MeV proton bombardment of 66Zn with current intensity of 180 μA (yield 11.2 mCi/μAh). Bleomycin (BLM) was labeled with [66Ga]GaCl3  相似文献   

8.
The mono- and bisligands complexes formed by rare earth cation (Sc, Y) with pentazolato anion or cyclo-P5 anion, the all-nitrogen counterparts of metallocenes or the all-phosphorus counterparts of metallocenes, have been studied at hybrid basis sets level with the DFT method. The geometric parameters, binding energy and the charge distributions of these complexes were characterized. And their stable orders were obtained. Monoligand complexes incline to become bisligands complexes due to their destabilization. The charge transferring between ligand and metallic cation has affinity with the stability of complex. The possibility of forming stable [M(η 5-E5)2] (M = Sc, Y, E = N, P) complexes is predicted and they are viable synthetic targets theoretically, especially Sc(η 5-N5)2.  相似文献   

9.
Synthesis of five binary complex salts with an [Ir(NH3)5Cl]2+ complex cation is described. The counterions are [ReCl6]2–, [IrCl6]2–, [ReBr6]2–, and Cl. A polycrystal X-ray diffraction study has been performed for [Ir(NH3)5Cl]2[ReCl6]Cl2, and its crystal structure has been determined. A series of Ir x Re1–x phases (0.5 x > 1) were obtained by reductive thermolysis. For the Ir-Re system, the history of the V/Z(x) dependence has been refined.Original Russian Text Copyright © 2004 by S. A. Gromilov, S. V. Korenev, I. V. Korolkov, K. V. Yusenko, and I. A. BaidinaTranslated from Zhurnal Strukturnoi Khimii, Vol. 45, No. 3, pp. 508–515, May–June 2004.  相似文献   

10.
This article presents, 122Sb (T 1/2 = 2.723 days, I β- = 97.59%) was produced via the natSn(p,xn) nuclear process at the AMIRS (Cyclone-30, IBA, Belgium). The electrodeposition experiments were carried out by potassium stannate trihydrate (K2Sn(OH)6) and potassium hydroxide. The optimum conditions of the electrodeposition of tin were as follows: 40 g/L natSn, 20 g/L KOH, 115 g/L K2Sn(OH)6, DC current density of 5 A/dm2 with a bath temperature of 75 °C. The electroplated Tin-target was irradiated with 26.5 MeV protons at current of 180 μA for 20 min. Solvent extraction of no-carrier-added 122Sb from irradiated Tin-natural target hydrochloric solution was investigated using di-n-butyl ether (C8H18O). Yields of about 3.61 MBq/μAh were experimentally obtained.  相似文献   

11.
The station for pions cancer therapy was operated at PSI from 1980 to 1992. After a cooling time of 12 years it’s made of copper beam dump was cut and samples were taken for analytical purposes. The sampling collected about 500 g of high active copper chips that can be used for separation of exotic radionuclides. The analyses by gamma spectrometry, LSC and AMS showed main nuclides present to be 60Co, 54Mn, 22Na, 65Zn, 26Al, 53Mn, 59Ni, 63Ni, 55Fe and 60Fe and 44Ti with a daughter nuclide 44Sc. In the frame of ERAWAST project a procedure combining selective precipitation and ion exchange for the separation of the rare radionuclides from the copper beam dump was developed. The proposed separation procedure is easy for remote controlled implementation in a hot cell. The ion exchange separation of Ni, Al, Mg, Ti and Fe was complete and high decontamination factors for copper and cobalt were achieved. Based on the developed procedure a remotely controlled system for separation of exotic radionuclides from the copper chips was set up. The full scale system was installed in a hot cell where high activity levels can be handled. In order to evaluate the reliability and functionality of the system extensive tests have been done. During the test period 13.86 g in total of the proton irradiated copper beam dump were processed for separation of 26Al, 59Ni, 53Mn, 44Ti and 60Fe. The results showed that the system was operational and the radionuclide separation was selective with high chemical yield. The procedure manages as well the generated liquid wastes containing high level of 60Co activity.  相似文献   

12.
DFT calculations of electric field gradient (EFG) tensors at the sites of 14N, 17O, and 2H nuclei are carried out to characterize the hydrogen bond (HB) interactions in the sulfapyridine crystal structure. One-molecule (monomer) and hydrogen-bonded hexameric cluster models of sulfapyridine are constructed according to available X-ray coordinates where the proton positions are optimized. Then, EFG tensors are calculated for both monomer and target molecule in the hexameric cluster of sulfapyridine to show the effect of HB interactions on the tensors. The calculated EFG tensors are converted to the experimentally measurable nuclear quadrupole resonance (NQR) parameters: quadrupole coupling constant (C Q ) and asymmetry parameter (η Q ). The results reveal different contribution of various nuclei to N-H⋯N and N-H⋯O HB interactions in the cluster where the N2 and O1 have major contributions. The computations are performed with B3LYP and B3PW91 functionals DFT method and 6-311+G* and 6-311++G** standard basis sets using the Gaussian 98 package.  相似文献   

13.
The design, fabrication, and testing of a 4H-SiC Schottky betavoltaic nuclear battery based on MEMS fabrication technology are presented in this paper. It uses a Schottky diode with an active area of 3.14 mm2 to collect the charge from a 4 mCi/cm2 63Ni source. Some of the critical steps in process integration for fabricating silicon carbide-based Schottky diode were addressed. A prototype of this battery was fabricated and tested under the illumination of the 63Ni source with an activity of 0.12 mCi. An open circuit voltage (V OC) of 0.27 V and a short circuit current density (J SC) of 25.57 nA/cm2 are measured. The maximum output power density (P max) of 4.08 nW/cm2 and power conversion efficiency (η) of 1.01% is obtained. The performance of this battery is expected to be significantly improved by using larger activity and optimizing the design and processing technology of the battery. By achieving comparable performance with previously constructed p–n or p–i–n junction energy conversion structures, the Schottky barrier diode proves to be a feasible approach to achieve practical betavoltaics.  相似文献   

14.
The structure of galactomannans isolated from seeds of G. delavayi and G. aquatica was studied by 1H and 13C NMR spectroscopy. It was found that the galactomannans consisted mainly of β-1-4-bound mannopyranoses, a part of which was substituted on the C-6 hydroxyl by terminal units of α-galactopyranose.__________Translated from Khimiya Prirodnykh Soedinenii, No. 1, pp. 12–13, January–February, 2005.  相似文献   

15.
14C releases in the stack air of the NPPs V1 and V2, Jaslovske Bohunice was determined during the year 2004–2010. Radioactivity concentration of 14C in the stack air was determined in the forms of inorganic 14CO2 and 14C n H m . The annual average activity concentration in the stacks air samples varies between 12 and 121 Bq m−3. NPP V1, starting with 45 Bq m−3 in 2005 is decreasing due to the shutting down of the reactors (the first reactor was shut down in December 2006 and the second reactor in December 2008). The average value of radioactivity concentration for power unit V2 was 32 Bq m−3 in 2004 and reached the value of 102 Bq m−3 in the first-quarter of the 2010. The average normalized yearly discharge rates were between 0.39 and 0.64 TBq GWe−1 year−1 (2005–2008), NPP V1 and 0.19–0.61 TBq GWe−1 year−1 (2004–first-quarter 2010) for NPP V2, Jaslovske Bohunice. Most of the discharged 14C is in a hydrocarbon form, (95% for Jaslovske Bohunice NPP V2), but the CO2 fraction may reach 37% in the air stack for Jaslovske Bohunice V1.  相似文献   

16.
2-Keto-D-gluconate (kG) is naturally produced in soils, sediments and rock faces through the microbial oxidation of glucose. Studies have qualitatively shown kG to enhance the dissolution of soil minerals. However, quantitative information, such as the log K values for the formation of metal–kG complexes, are not available. This paper presents the results of potentiometric titration studies that employ H+ and Ca2+ ion selective electrodes (ISEs) to determine the conditional ion association constants (log Q values) for the protonation and deprotonation of kG and the formation of Ca–kG complexes. The experimentally-determined log Q values were then converted to the corresponding ion association constants (the zero ionic strength condition; log K values) by employing a modified Davies equation for charged species and the Setchenów equation for neutral species. The log K values were determined by potentiometric titrations at constant kG concentration, varied ionic strengths, 25 or 22 C, and in the absence of CO2. The computer model GEOCHEM-PC was used to determine the aqueous speciation of ions other than kG and the computer model FITEQL was used to estimate conditional log Q values for reactions in the various chemical models. Based on our evaluations, equilibrium constants for the following reactions were determined: H++ kG ⇌ HkG0, log Ka1 = (3.00 ± 0.06), kG⇌ H–1kG2–+ H+, log Ka–1 = –(11.97 ± 0.41), and Ca2++ kG⇌ CakG+, log K101 = (1.74 ± 0.04).  相似文献   

17.
In recent years, there has been a rapid expansion in the use of radio nuclides for therapeutic purposes. Thulium–167 is an important radionuclide (T 1/2 = 9.25 d) due to it could be used for tumor and bone studies in nuclear medicine. 167Tm complexed with hydroxy ethylene diamine tetra-acetic acid (HEDTA) could be used with the aim of bone imaging. 167Tm emits a prominent γ ray of 208 keV energy and low energy electrons. This study describes calculations on the excitation functions of 165Ho(α,2n)167Tm, 167Er(p,n)167Tm, natEr(d,xn)167Tm and natEr(p,xn)167Tm reactions by ALICE/ASH (hybrid and GDH models) and TALYS-1.0 codes. In addition, calculated data by codes were compared to experimental data that earlier were published and TENDL-2010 database. Moreover, optimal thickness of the targets and physical yield were obtained by SRIM (stopping and range of ions in matter) code for each reaction. According to the results, the 167Er(p,n)167Tm and 165Ho(α,2n)167Tm reactions are suggested as the best method to produce 167Tm owing to minimum impurities. The TALYS-1.0 code, predict the maximum cross-section of about 382 mb at 11 MeV and 849 mb at 26 MeV for 167Er(p,n)167Tm and 165Ho(α,2n)167Tm reactions, respectively. Finally, deposition of natEr2O3 on Cu substrate was carried out via the sedimentation method. The 516 mg of erbium(III)oxide with 103.2 mg of ethyl cellulose and 8 mL of acetone were used to prepare a natEr2O3 layer of 11.69 cm2. 167Tm was produced via the natEr(p,n)167Tm nuclear process at 20 μA current and 15 → 7 MeV protons beam (1 h). Yield of about 3.2 MBq 167Tm per μA h were experimentally obtained.  相似文献   

18.
172Lu due to its suitable (T 1/2 = 6.7 days) and high detection sensitivity, is used as a radiotracer in different fields. 172Lu appears to be suitable as a long-lived rare-earth tracer for compound labelling and biodistribution studies. In the present study, excitation functions via 172Yb(p,n)172Lu, natYb(p,xn)172Lu, 172Yb(d,2n)172Lu and natYb(d,xn)172Lu reactions were calculated by ALICE/91, ALICE/ASH and TALYS-1.2 codes. Deposition of natYb2O3 on Cu substrate was carried out via sedimentation method for the production of 172Lu. Cementation separation process and liquid–liquid extraction (LLX) of no-carrier-added (nca) radiolutetium from irradiated ytterbium(III)oxide target hydrochloric solution was described using Na(Hg) amalgam, α-hydroxyisobutyric acid (α-HIB) and di-(2-ethylhexyl)phosphoric acid (HDEHP).  相似文献   

19.
The radionuclide vanadium-48 (T 1/2?=?16?d, ?? +=?49.5?%) could be employed to positron emission tomography. In this Study, 48V excitation function for the nat/49/48Ti(p,x)48V and the 48Ti(d,2n)48V nuclear reactions were calculated by ALICE/ASH code. Then recommended thickness of the targets according to the SRIM-2010 code was calculated; consequently, the theoretical integral yields were computed for all reactions by the computer software. As a result, the 48Ti(p,n)48V reaction was determined as the best reaction. Ti target was prepared by sedimentation method to produce 48V throughout accelerator proton bombardment.  相似文献   

20.
A method for the separation of no-carrier-added arsenic radionuclides from the bulk amount of proton-irradiated GeO2 targets as well as from coproduced radiogallium was developed. The radionuclides 69Ge and 67Ga produced during irradiation of GeO2 were used as tracers for Ge and Ga in the experiments. After dissolution of the target the ratio of As(III) to As(V) was determined via thin layer chromatography (TLC). The extraction of radioarsenic by different organic solvents from acid solutions containing alkali iodide was studied and optimized. The influence of the concentration of various acids (HCl, HClO4, HNO3, HBr, H2SO4) as well as of KI was studied using cyclohexane. The optimum separation of radioarsenic was achieved using cyclohexane with 4.75 M HCl and 0.5 M KI and its back-extraction with a 0.1% H2O2 solution. The separation leads to high purity radioarsenic containing no radiogallium and <0.001% [69Ge]Ge. The overall radiochemical yield is 93 ± 3%. The practical application of the optimized procedure in the production of 71As and 72As is demonstrated and batch yields achieved were in the range of 75–84% of the theoretical values.  相似文献   

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