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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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MPGeγ探测器的γ能量信号与4πΔEβ探测器的β射线能损信号符合后再与BGO探测的β+衰变的正电子湮灭511keV γ信号作反符合组成一种新的探测系统. 该系统可使γ谱测量的康普顿本底下降约一个数量级. 对缺中子同位素衰变γ射线的探测作强抑制的同时,丰中子同位素衰变γ射线的探测仍能保持相对单谱为(46±3)%的高效率. 使用该系统对已被合成的丰中子核素208Hg的半寿命进行了一次新的测定. 所得新的208Hg半寿命测定值41.5+min,与以往用放射化学母牛法给出的结果一致,测量误差有较大改进. 相似文献
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MG转轮收集探测系统的检验实验 总被引:3,自引:2,他引:1
利用SFC提供的束流对新建的转轮系统进行了检验实验,得到了相关的实验结果.实验证明了该装置的可靠性,为进一步开展超重核的研究完成了预实验.A new set up was built in IMP. The reaction 24Mg+232Th was performed as a test experiment for this set up. The decay chains of 252No and 253No have been observecl in this reaction. The results show that this set up is efficient for the rear events and it is possible to use this set up in the future experiment. 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