^212Pb,^212Bi标记金属硫蛋白

研究了用２１２Ｐｂ、２１２Ｂｉ和２１２Ｐｂ－２１２Ｂｉ平衡混合物分别标记金属硫蛋白Ｃｄ－ＭＴ２及这些标记物在ＳｅｐｈａｄｅｘＧ－１００柱上的淋洗行为和衰变趋向。实验结果表明，在生理ｐＨ条件下，Ｃｄ－ＭＴ２首先与２１２Ｂｉ结合，其标记率接近１００％。     

北京地区大气中^212Pb浓度的测定及所致居民剂量

本文介绍了用ＮａＩ（Ｔｌ）－塑料反符合低本底γ谱仪测定大气中￣（２１２）Ｐｂ浓度的方法以及于１９８８．２－１９８９．１对北京地区３２９ｄ空气中￣（２１２）Ｐｂ浓度的测定结果。结果表明，大气中￣（２１２）Ｐｂ浓度呈对数正态分布，算术均值和单次测量标准差分别为０．５４和０．４０Ｂｑ·ｍ￣（－３）；几何均值和几何标准差分别为０．４４Ｂｑ·ｍ￣（－３）和２．０。每年７、８月份雨季￣（２１２）Ｐｂ浓度最低（０．４２Ｂｑ·ｍ￣（－３））；冬季取暖季节最高（０．６６Ｂｑ·ｍ￣（－３））；￣（２１２）Ｐｂ浓度的昼夜变化亦很大，凌晨００－０４时最高，午后１２－１８时最低，最高／最低为４．８。根据实际测量值估算了北京地区居民吸入所子体所致公众年有效剂量为２１０μＳｖ，室内１６０μＳｖ，室外为５０μＳｖ。     

^188W—^188Re发生器的研制

以酸性氧化铝为吸附剂，制备了一个１１８ＭＢｑ的１８８Ｗ－１８８Ｒｅ发生器，并对发生器性能进行了为期４个月的检测。结果表明，１８８Ｒｅ的淋洗产额在８０％—９０％之间，１８８Ｗ的穿透率约为１．０×１０－４％。由于采用了较大高径比的交换柱，使１８８Ｒｅ的放射性比活度较高，能满足用于放射免疫治疗研究的抗肿瘤单克隆抗体标记的要求。     

Dynamic Study on Damped Reactions of ^244Pu＋^244Pu,^238U and^238U and ^197Au＋^197Au

In most attempts to produce superheavy elements（SHE）, the complete fusion reactions have successfully been tried. Since the 70＇s the elements from Z=107 to 116 were synthesized in the ＂cold fusion＂ reactions with lead and bismuth targets and ＂hot fusion＂ reactions with actinite targets. However,     

Measurement of ^90Sr and ^90Y Under Unbalance by Bremsstrahlung

DC-DC开关功率变换器在通信、军事设备、计算机、仪器仪表及工业自动化设备等电子工业和军工系统中有着极其广泛的应用。近年来，DC—DC开关功率变换器动力学性质的研究发现，该变换器中有着十分丰富的非线性动力学行为，例如DC—DC开关功率变换器经过一系列分岔如倍周期分岔、边界碰撞分岔等可达到混沌。由于DC-DC开关功率变换器运行中，电路拓扑结构随时间改变，使其成为一个典型的分段光滑非线性动力系统。     

Dynamic Study of Fusion Reactions of ^40,48Ca＋^90,96Zr

Based on the Improved Quantum Molecular Dynamics Model the fusion reactions of ^40,48Ca＋^90,96Zr are studied by making a more rigorous treatment of the initial condition. The study shows us that： （1） the calculated fusion cross sections for all four reactions of ^40,48Ca＋^90,96Zr are in good agreement with experiment data;     

P507萃淋树脂分离^90Sr—^90Y

一、引言萃淋树脂在分析分离及湿法冶金中取得了良好的应用效果。用它来分离性质相近的元素有不少报道,有人以D_2EHPA为固定相,用萃取色层法分离~(90)Sr-~(90)Y。但是,用P_(207)萃淋树脂来分离~(90)Sr-~(90)Y,尚鲜见报道。本文对P_(507)萃淋树脂的基本性能进行了测试。在探讨~(90)Sr-~(90)Y在该萃淋树脂上吸附淋     

Nuclear Sata Sheets for A = 212

Detailed level schemes, decay schemes, and the experimental data on which they are based are presented for all nuclei with mass number A = 212. The experimental data are evaluated; inconsistencies and discrepancies are noted; and adopted values for level and gamma-ray energies, gamma intensities, as well as other nuclear properties are given.     

<Superscript>212</Superscript>Pb/<Superscript>212</Superscript>Bi Generator for nuclear medicine

A scheme for producing the α-emitters ²¹²Pb and ²¹²Bi, to be used in a promising method of diagnostics and therapy in oncology – radioimmunotherapy, is proposed. The technology is based on two generators operating in tandem: ²²⁸Th/²¹²Pb and ²¹²Pb/²¹²Bi. The first one is based on separation from an initial solution containing thorium isotopes and gaseous ²²⁰Rn, which secures the purity of the desired products ²¹²Pb and ²¹²Bi. For a ²²⁸Th/²¹²Pb model generator, the efficiency of ²²⁰Rn extraction from solution was ~60%. After conditioning, the ²¹²Pb solution from the ²²⁸Th/²¹²Pb generator was used to charge a column, which functioned as a ²¹²Pb/²¹²Bi generator, with a cation exchanger.     

Selective Gaseous Electro-Deposition of Lead-212 and Tellurium-208 from RdTh Source

Fractional electro-deposition of ²¹²Pb and ²⁰⁸T1 from RdTh source using a capsule equipped with three electrodes was carried out under normal pressure. The experiment was conducted with variations brought to the applied voltage, the interval between the electrodes, time allowed for deposition and grid conditions. The active deposit thus obtained was examined by radiochemical and autoradiographical methods.

Measurements of the active deposits on the electrodes showed that ²¹²Pb had deposited on the grid net, and ²⁰⁸T1 on the target. The mechanism of the electro-deposition process under electric field with and without a grid is discussed on the basis of the decay pattern shown by each nuclide.     

^176Hf（n,2n）^175Hf和^185Re（n,2n）^184Re^m,g反应截面研究

用中国原子能科学研究院ＨＩ－１３串列加速器,高压倍加器和北京大学４．５ＭＶ静电加速器分别获得能量为１０－１２,１４和１８ＭｅＶ的中子,了＾１７６Ｈｆ（ｎ,２ｎ）和＾１８５Ｒｅ（ｎ,２ｎ）的反应堆面,并与现有的实验数据作了比较,初步搞清了分歧的主要原因和激发函数的走向。     

~(107)Ag(d,2n)~(107)Cd和~(109)Ag(d,2n)~(109)Cd反应的激发函数

用13.4MeV的氘束轰击天然银迭靶,银箔前后用铝箔作捕集减能膜。实验确定了~(107)Ag(d,2n)~(107)Cd和~(109)Ag(d,2n)~(109)Cd反应的激发函数,同时作了理论计算。由结果可见,实验值与理论值吻合得很好。     

非晶态合金（Fe1—xYx）84B16的穆斯堡尔谱学和磁学研究

用穆斯堡尔效应和磁测量方法对非晶态薄带(Fe_(1-x)Y_x)_(84)B_(16)(0≤x≤0.21)进行了研究。实验结果证实在所研究的样品中存在短程有序相互作用和由于钇替代而产生的不均匀区域。