氯化亚铊(~(201)Tl)注射液和~(203)Pb水溶液中杂质元素的ICP-AES法分析

氯化亚铊(~(201)Tl)注射液是诊断心肌梗塞、缺血等症的性能优越、获得广泛应用的放射性药物。一些发达国家均已相继试制成功,并大量生产以满足临床的需要。我所放射性氯化亚铊(~(201)Tl)注射液研制组利用本所回旋加速器所产生的30MV质子辐照天然铊靶而获得~(201)Tl。其核反应为:     

萃取色层分离/ICP-AES法测定钆铀氧化物中的杂质

研究了钆铀氧化物中29种杂质元素的测定。采用CL-TBP从硝酸溶液中萃取色层分离基体铀，所得含杂质及钆的淋出液以电感耦合等离子体原子发射光谱仪采用多组分图谱拟合法(MSF)测定。研究了MSF模型的建立与考查、不同杂质浓度下的回收率等。结果表明，方法对钆铀样品中29种杂质元素，即Al、Ba、Ca、Co、Cr、Cu、Fe、Li、Mg、Mn、Mo、Na、Ni、Ti、Zn、Ta、W、Th、Bi、Pb、Sn、V、In、Ag、B、Cd、Sm、Eu、Dy的测定准确可靠。对于其它杂质含量相当的铀／钆化合物，通过适当的处理和转化，也可采用本方法测定。     

Extraction of U（VI） and Th（IV） with a novel extractant N,N‘—tetrahexylmalonamide （THMA） in toluene

The dependence of THMA extraction behaviour for U(VI) and Th(IV) on nitric acid concentration,THMA concentratioin and molecular structure of extracted complex has been studied.For nitric acid solutions of 3.0 mol/L a coordinative mechanism may possibly dominate in the extraction of metal catioins,The complex composition of UO2(NO3)2(THMA)2,Th(NO3)4(THMA)2 and Th(NO3)4(THMA03 are proved.     

Determination of UO2(s) dissolution rates in a hydrogen peroxide medium as a function of pressure and temperature

A continuously stirred flow-through tank reactor has been developed and successfully used to determine rates of dissolution of powdered samples of uranium dioxide at pressure and temperature conditions above the ambient values. The experiments have been performed in a temperature range from 20 to 50 °C and a total hydraulic pressure ranging from 1 to 32 bar. Experiments have been performed in a test solution containing 10⁻⁴ mol/L of H₂O₂, 3 × 10⁻³ mol/L of NaHCO₃ and, finally, NaClO₄ to get a constant ionic strength of 0.1 mol/L. An empirical equation has been obtained that describes the results in the experimental range studied and gives a good concordance with values obtained at ambient conditions in other works. On the other hand, scanning electron microscopy (SEM) has shown that the solid surface has homogeneously reacted, and, in addition, no secondary solid phase has been formed on the UO₂ surface.     

A Novel Combination of Immunoreaction and ICP-MS as a Hyphenated Technique for the Determination of Thyroid-stimulating Hormone (TSH) in Human Serum

The novel coupling method based on the hyphenation of immunoreaction with ICP-MS is developed and applied to the determination of thyroid-stimulating hormone (TSH) in human serum. In this system, TSH is firstly captured by anti-TSH monoclonal antibodies immobilized on a solid support. Biotinylated anti-TSH monoclonal antibodies and Eu3 -labelled streptavidin are then added to form the complex capturing andbody-TSH-biotinylated anti-TSH antibody-Eu3 -labeled streptavidin. After unbound reactants are washed away, Eu3 bound to the complex is extracted by     

Experimental investigation and CFD validation of countercurrent flow limitation (CCFL) in a large-diameter PWR hot-leg geometry

ABSTRACT

Countercurrent flow limitation (CCFL) is a phenomenon that consists of several flow patterns occurring simultaneously which produces a complex gas/liquid interface and interfacial momentum transfer, thus making it one of the most challenging two-phase flow configurations for computational fluid dynamics (CFD) validation. Numerous experimental investigations have been carried out in recent years regarding this, but most of those investigations were performed in small-diameter pipes or in non-pipe geometries (rectangular cross sections). A review of these experimental investigations has shown that the scale and geometry of the test section has a large impact upon the onset and characteristics of the CCFL. In order to provide a better understanding of this phenomenon in an actual pressurized water reactor (PWR) hot-leg geometry at a relatively large-diameter and scale, a test facility with a ～1/3.9 scale and a 190 mm inner diameter was constructed. Experiments were carried out at atmospheric pressure using water and air. High-speed recording was used to acquire high-quality images of the air/water interface. CCFL mechanisms, flow patterns, and the limits of the onset of CCFL and deflooding were experimentally identified. CFD simulations of two representative cases were carried out and assessed against experimental results. The analysis of the CFD simulations has provided insights into the improvements necessary for the accurate simulation of CCFL in large-scale geometries.     

On the Tritium Breeding Capability of Flibe, Flinabe, and Li20Sn80 in a Fusion-Fission (Hybrid) Reactor

In a commercial (DT) driven fusion reactor, the tritium breeding ratio per incident fusion neutron must be greater than 1.05 to maintain tritium self-sufficiency for the driver. In this study tritium breeding capability of three different coolants, namely Flibe (LiF·BeF₂), Flinabe (LiF·NaF·BeF₂), and Li₂₀Sn₈₀ in a (DT) driven fusion-fission (hybrid) reactor was investigated for different refractory alloys (W-5Re, TZM, T111, and Nb-1Zr) as structural material. Neutron transport calculations were conducted with the help of SCALE 4.3 SYSTEM by solving the Boltzmann transport equation with code XSDRNPM. The contribution of Flibe, Flinabe, and Li₂₀Sn₈₀ with respect to ⁶Li enrichment in their lithium content to overall TBR was investigated. In addition, the effect of structural material type on TBR was examined.