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描述了硫酸铵溶液中铀矿坑水样品中铀的电沉积层特性。 电沉积液为10 ml 0.8 M的硫酸铵溶液, 电流密度0.6 A/cm2, pH值为2.5, 电镀1 h。 电沉积经化学分离后的水样品和电沉积的纯硝酸铀酰样品进行了比较, 并对二者分别做了红外(IR)光谱、 扫描电镜(SEM)、 元素分析以及α能谱测量。 IR谱上铀酰离子的反对称伸缩振动峰在887 cm-1附近, 使电沉积在不锈钢片上的铀主要以铀酰离子水合物的形式存在, 有一部分NH+4以NH3的形式替代水合物中的水, 使电沉积层中铀的化合物形式为UO2(OH)2·xNH3·yH2O或者UO2(OH)2-x·(ONH4)x·yH2O, 铀酰离子通过链的形式形成聚合结构。 SEM照片显示电沉积层均匀, 没堆积成团现象出现。 α谱表明电沉积层中铀的同位素主要是238U和234U, 相应的α能量峰4198和4773 keV很显著, 没其它峰的干扰。 Characteristics of electrodeposited uranium films of uranium ore water sample in ammonium sulphate was investigated in this work. The optimized electrodeposited conditions were as follows: electrolyte was ammonium sulphate of 0.8 M, and current density at the cathode was 0.6 A/cm2, electrolyte pH value was 2.5, the time of plating on the electrodeposition was 1 h. In this situation, the uniform, thin and adheresive films were produced by electrodeposition method. Two samples were made, one electrodeposition of pure uranyl nitrate, and another electrodeposition of uranium ore water sample after chemical separation. Characteristics of electrodeposited uranium films of uranium ore water sample after chemical separation was studied, making comparisons with electrodeposited films of uranyl nitrate. The analysis of film characteristics was done through infrared (IR) spectrum, scanning electron microscopy(SEM), element analysis and α spectrum measurment. According to Fourier transform infrared spectra, the asymmetric stretching vibration band of uranyl group is around 887 cm-1. In addition, according to IR spectrum, we know that uranium exists mainly as the form of hydrated polymeric compound in the film. Electrodeposited uranium films also included many NH+4. Polymeric structures of variable composition were present in the electrodeposited samples, with the unit monomeric formula UO2(OH)2·xNH3·yH2O or UO2(OH)2-x·(ONH4)x·yH2O. Scanning electron microscopy shows that the two samples have similar surface characteristics and no cluster is observed. The samples were also measured by spectrometer equipped with Passivated Implanted Planar Silicon(PIPS) detector. From the α spectrum, we know that isotopes of uranium in the film are 238U and 234U. 235U is not found in the α spectrum. It also shows that the chemical separation process can isolate uranium from other interfering elements effectively, the result of chemical separation is very satisfactory and electrodeposited process is rather efficient. Source electrodeposited in ammonium sulphate through optimized conditions satisfies the need of high resolution α spectrum. 相似文献
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利用25 MeV/u 40Ar+Se中能重离子核反应, 制备包含24种元素在内的多重示踪剂, 通过对元素γ谱的分析, 研究了正常鼠和肿瘤鼠体内微量元素的分布及代谢。Mg, Sr, Ga, As, Sc, V, Cr, Mo, Co, Fe, Y, Zr, Nb和Ru等元素在肿瘤鼠的粪便和尿液中的排泄时间与正常鼠不同。 肿瘤鼠与正常鼠相比, Na, Mn, Fe和Co的排泄变化较大, 肿瘤鼠的排泄率较正常鼠高; 而Ca, Y, Zr和Mo的排泄率肿瘤鼠则较正常鼠低; 在正常鼠脏器、 组织和血液样品中测出了Na, Rb, Ga, Sc, As, Zn, V, Cr, Mn, Co, Fe、Y, Zr, Tc, Ru, Ag和In等17种元素, 肿瘤鼠检测出了除Zn和As之外的其它15种元素。 几乎所有的元素在正常鼠中的吸收均比肿瘤鼠高。 大部分元素分布在肝、 肾和毛皮以及实体瘤中, 而Fe和Na在肿瘤组织则没有检测到。 A radioactive multitracer solution of the 24 elements, e.g. Be, Na, K, Rb, Mg, Ca, Sr, Ga, As, Sc, V, Cr, Mn, Co, Fe, Zn, Y, Zr, Mo, Nb, Tc, Ru, Ag and In, was obtained from the nuclear reaction of 25 MeV/u 40Ar+Se with a series of chemical process. The multitracer solution was orally administered to normal and muscular tumour bearing mice of male Balb/c mice. Urine and faeces samples of mice were collected. The two group mice were sacrificed after 96 h. The uptake of 17 elements, Na, Rb, Ga, As, Sc, V, Cr, Mn, Co, Fe, Zn, Y, Zr, Tc, Ru, Ag and In, were simultaneously detected in normal mice while 15 elements, Na, Rb, Ga, Sc, V, Cr, Mn, Co, Fe, Y, Zr, Tc, Ru, Ag and In, were simultaneously detected in tumour bearing mice. Our results indicate that the majority of the detected elements were distributed in liver, kidney, pelt, tumour while a small fraction of the biotrace elements were distributed in heart and spleen (tumour bearing mice) in the two groups of mice. The higher concentrations of Fe, Na, Mn were detected in heart or kidney of normal mice. Na, Mn, Fe and Co showed better absorption in most tissues in the normal mice, except for Na and Mn in heart. 相似文献
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采用分子镀方法研究了异丙醇-硝酸体系中两极间距离、电流密度、加入HNO3的量和分子镀持续时间对镀层性能和电沉积效率的影响,确定了制备Tb,Dy 和Ho 靶的最佳工艺条件。同时也探索了在异丁醇-硝酸体系中,分子镀持续时间和电流密度对Tb 靶电沉积效率的影响。因Tb,Dy 和Ho 三种元素化学性质相近,故采用了相同的工艺条件: 两极间最优距离为15 mm,电流密度为5.7 mA/cm2,加入0.1mol/L HNO3 400 L,分子镀时间为1 h。用分光光度法测得各靶的沉积效率均高于85%;利用扫描电子显微镜(SEM)对部分靶的表面形貌分析后发现靶面结构均匀致密;利用能谱仪(EDS) 对靶子进行了定性和半定量分析;利用红外光谱法对靶膜化学成分进行了分析,发现靶膜成分结构复杂,不是由一种化合物组成。目前制得的Tb 靶和Ho 靶已用于中国科学院近代物理研究所加速器SFC 低能核化学终端上,利用19F 束流轰击,分别产生了W和Os 的短寿命同位素,从而成功完成了Sg(Z =106) 和Hs(Z =108) 的模型试验。Preparation of Tb, Dy and Ho targets from the mixture of isopropanol and nitricacid solution are studied by using molecular plating technique. To determine the optimum conditions for the deposition process,the effect of distance between the two electrodes, current density, volume of 0.1 mol/L nitric acid, deposition time on the quality and electrodeposition yield of the target films are investigated individually. Preparation of Tb targets from the mixture of isobutylalcohol and nitricacid solution are also studied by using molecular plating technique. Depending on the similar chemical properties of Tb, Dy and Ho, the same process conditions are used.The suitable distance between the two electrodes is 15 mm. The current density is 5.7 mA/ cm2. The volume of nitric acid (0.1 mol/L) is 400 L. With the spectrophotometry method, the electrodeposition yields for all the targets prepared are found to be higher than 85% after one hour’s deposition. The morphological structure of some targets are characterized by scanning electron microscope (SEM) and it can be seen that the surface of the targets are uniform and intact. With EDS method, the composition of some targets are found to be very pure. The chemical structure of the targets are analyzed by Infrared Spectroscopy. It is found that the chemical structure of the targets are complex and the target membrane is not composed by only one compound. Short lived isotopes of W and Os were produced from natural Tb and Ho targets bombarded by 19F beam at the SFC low energy radiochemical terminal of Institute of Modern Physics, Chinese Academy of Sciences, respectively,and were successfully applied in the model experiment of Sg (Z =106) and Hs (Z =108). 相似文献
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探讨了带有肟胺基官能团材料的制备、 吸附铀的机理及其对盐湖卤水中铀的吸附效果。 利用电子束辐照法制备肟胺化无纺布, 红外光谱显示材料中含有肟胺基存在, 表明肟胺基成功的接枝在无纺布基体上。 研究了铀溶液的初始pH、 吸附时间和固液比等因素对铀吸附效果的影响, 吸附过程中络合反应为控速步骤。 肟胺化纤维和肟胺化无纺布对盐湖卤水样品具有较高的吸附效率, 可以作为盐湖提铀的备选材料。 Amidoximed fiber and fabric were synthesized with the purpose of adsorbing U in salt lake and the adsorption mechanism was discussed. IR indicated that amidoxime was graft to the fabric which was irradiated by electron beam. Batch experiments were conducted to study the effects of initial pH, amount of adsorbent, shaking time on uranium sorption efficiency. The sorption of uranium on amidoxime was dependent on the pH value of the solution, and the optimal pH was 4.0. Uranyl was taken out from solution in the form of complex with amidoxime. Uranium recovery efficiency from salt lake was more than 50% with amidoximed fiber and fabric which can be used as uranium extraction material. 相似文献
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