CesiP的交换性能及其在^201Pb—^201Tl母子体系中的应用

本文通过11种无机离子交换剂对Pb~(2+),Tl~(3+)及T1~+交换性能的研究,选择CeSiP进行~(201)Pb-~(201)Tl分离。研究了其交换性能、穿透容量及其交换柱的淋洗性能.制备了~(201)Pb-~(201)Tl母子体系.该母子体系可得到产额为83.5％,核纯>99.0％的~(01)T1.     

甲状腺滤泡型腺瘤^201TICl显像观察

通过采和＾２０１ＴＩＣｌ对＾９９ｍＴｃＯ４＾－甲状腺显像的“冷结节”进行再显像，观察＾２０１ＴＩＣｌ显像对甲状腺滤泡型腺瘤临床应用的意义，在３０例进行＾２１ＴＩＣｌ显像患者中，仅选择其中１９例经手术病理证实状腺滤泡型腺瘤的患者作分析，其＾２０１ＴｌＣｌ显像结果为（－）６例，（＋）１０例，（＋＋）３例，总阳性例数为１３／１９例，甲状腺滤泡型腺瘤呈为良性，但有浓聚＾２０１ＴｌＣｌ能力，此等病例应长期随     

^201TlCl注射液中铊载体的分光光度测定

研究了分光光度法测定２０１ＴｌＣｌ注射液中载体铊的含量。用溴水作氧化剂，将Ｔｌ（Ⅰ）氧化为Ｔｌ（Ⅲ），并加入磺基水杨酸除去过量溴，以对硝基苯重氮氨基偶氮苯（简称镉试剂）为显色剂，聚乙二醇辛基苯基醚（乳化剂ＯＰ）为胶束增溶剂在水相中直接测定Ｔｌ（Ⅲ），显色体系为ｐＨ＝１１．７的ＮＨ４Ｃｌ－ＮＨ４ＯＨ缓冲溶液，配合物的最大吸收波长为４６９ｎｍ，摩尔吸光系数为１．３７×１０４ｍ２／ｍｏｌ。     

中试厂201子项现场焊接质量控制

本文结合中试厂201子项现场管道、设备焊接质量要求，从“人、机、料、法、环”五要素分析做好现场焊接质量控制，确保现场管道、设备的焊接质量，已在现场焊接施工作业中，起到一定的作用，对其他核设施施工现场的焊接质量控制有一定的参考价值。     

一个新的~(201)Pb-~(201)Tl发生器的研制

本文描述了从母体~(201)Pb分离子体~(201)Tl的一种新方法。该法采用无机离子交换剂柱,先将靶物溶解液通过离子交换柱,~(201)Pb~(2+)吸附在无机离子交换剂柱上,其他离子,如Tl~(3+)、Cu~(2+)等不吸附而通过离子交换柱被除去,经过32小时,即当子体~(201)Tl生长达到高峰时,以0.1mol/lHCl(0.7％Cl_2)溶液淋洗~(201)Tl。研究结果表明,本发生器具有简单、快速、效果良好的特点。     

~(200)Tl、~(201)Tl、~(202)Tl的制备

本文采用Hg(d,xn)反应制备了铊-201制备方法如下。 外靶靶衬为一个边缘凸出的椭圆形铜材,表面有许多凹槽,在靶衬表面仔细铺一层氧化汞粉末,粉末表面覆上两层6μm的铝箔,其边缘以铜片固定并以锡焊焊牢。该靶头在本所自制的外靶装置上,以12.5MeV的氘束轰击,最大束流6μA,总共20μA。     

铊-201静息-运动心肌灌注显像

近十年来,利用~(201)Tl心肌灌注显像诊断缺血性心绞痛、急慢性心肌梗塞的定位、旁路手术疗效的观察与预后等已引起广泛的重视。为了取得实践经验,我们应用~(201)Tl进行了临床观察。本文报告初步结果。     

201Tl心肌灌注显像对识别冠脉狭窄程度和范围的临床价值

心肌缺血可导致心肌收缩能力下降[1]、心室腔扩大, 在负荷条件下尤为显著.     

半定量法201Tl双时相显像鉴别诊断甲状腺冷结节

为探讨甲状腺冷结节2 0 1Tl双时相显像的实用价值 ,取甲状腺单个冷结节患者 87例 ,静脉注射2 0 1Tl 12 1MBq后 15min显像及 12 0min延迟显像。按半定量法分别进行感兴趣区计数 ,计算结节组织与正常组织摄取比 (15min记为ER ,延迟记为DR)及滞留指数 [RI =(DR -ER) /ER×10 0 %]。结果表明 ,ER、DR和RI的恶性与非恶性组之间差异显著 (P <0 .0 5 )。囊性腺瘤者ER、DR和RI均明显低于恶性者 (P <0 .0 1) ;炎症者与恶性者比较差异不显著 (P >0 .0 5 )。半定量法的灵敏度、特异性和诊断正确率明显优于目视法 ,ER分别与DR、RI之间比较有显著性差异 (P <0 .0 5 )。显像结果提示 ,半定量法2 0 1Tl诊断显像可明显提高甲状腺单个冷结节的良、恶性质的诊断效率 ,具有临床应用价值。     

甲状腺滤泡型腺瘤~(201)TlCl显像观察

通过采用201TlCl对99mTcO4甲状腺显像的“冷结节”进行再显像，观察201TlCl显像对甲状腺滤泡型腺瘤临床应用的意义．在30例进行201TlCl显像患者中，仅选择其中19例经手术病理证实为甲状腺滤泡型腺瘤的患者作分析，其201TlCl显像结果为（－）6例，（＋）10例，（＋＋）3例，总阳性例数为13／19例。甲状腺滤泡型腺瘤虽为良性，但有浓聚201TlCl能力，此等病例应长期随访，观察甲状腺癌发生的情况。     

~(201)Tl心肌灌注显像潘生丁试验在心肌梗塞诊断中的应用

本文介绍了103例心肌梗塞患者~(201)Tl心肌灌注显像潘生丁试验的结果,并对55例同时进行平面及断层显像的资料进行了分析。在断层即刻和延迟显像中灌注异常阳性率分别为93％及80％。诊断LAD、RCA和LCX各支病变的灵敏度为93％、89％及73％。51例有灌注异常的患者中有40例(72％)显示填充现象,提示同时存在有缺血性病变。结果显示~(201)Tl心肌灌注显像潘生丁试验不仅有助于心肌梗塞的诊断和病变部位及范围的了解,还有助于预后的估测和治疗方案的确定。     

用井型 Nal(TI)探测器绝对测量~(125)I活度

本文叙述了用井型 NaI(T1)探测器的符合脉冲高度分布绝对测量~(125)I 活度的方法。用目前比较精确的核参数推导了计算公式。初步研究了样品体积和样品瓶的几何条件对测量结果的影响。测量结果的合成不确定度小于1%.     

PIXE characterization of CsI(Tl) scintillators used for particle detection in nuclear reactions

Particle-Induced X-ray Emission has been used to measure Thallium concentration in several CsI(Tl) scintillators from different manufacturers, in order to check their nominal declared values and correlate their behaviour with actual Tl concentration. Indeed, both Tl doping level and its uniformity affect light emission of these detectors, which are largely employed in nuclear physics experiments.In some of the examined crystals Tl concentration values from PIXE measurements came out to be quite different from those declared. This allowed us to explain apparent anomalies in the trend of their α/γ-induced light yield ratio versus Tl content. In some cases, the presence of unexpected contaminants was also pointed out.     

氯化亚铊(~(201)Tl)放射化学纯度测定方法的选择

本文以同一批氯化亚铊和氯化铊为供试品,采用醋酸纤维薄膜电泳、纸电泳、预饱和纸层析及非饱和纸层析等不同方法进行比较,发现上述方法均能将供试品中的铊~(201)Tl(Ⅰ)和铊~(201)Tl(Ⅲ)分离。以氯化亚铊(~(201)Tl)作供试品时,测得~(201)Tl(Ⅰ)数值接近;以氯化铊(~(201)Tl)作供试品时,四种方法测定的~(201)Tl(Ⅲ)的结果很不一致。采用Na_2HPO_:丙铜=10:90为展开剂,预饱和上行纸层析的方法,能有效地测出供试品中~(201)Tl(Ⅲ),误差小,重复性好。为此,推荐上述方法为氯化亚铊(~(201)Tl)放射化学纯度测定方法     

Maximum scintillation yields in NaI(Tl) and CsI(Tl) crystals estimated from the scintillation model for liquid rare gases

The maximum scintillation yields in NaI(Tl) and CsI(Tl) crystals were estimated theoretically by applying the scintillation model for liquid rare gases to crystal scintillators. Average energies required to produce one scintillation photon in the maximum scintillation yield, W_so, were estimated to be 10.6 ± 0.3 or 11.6 ± 0.3 eV for NaI(Tl) and 11.6 ± 0.3 or 12.5 ± 0.3 eV for CsI(Tl). The new experiment on scintillation yields gives W_so of 10.8 ± 2.0 eV for NaI(Tl) and 11.3 ± 2.1 or 9.3 ± 1.7 eV for CsI(Tl). The values show good agreement with the theoretical estimations. These results demonstrate that the scintillation model in liquid rare gases is applicable to inorganic scintillators such as NaI(Tl) and CsI(Tl) crystals.     

Time resolved on-line nuclear orientation (TR-OLNO)

Conventional on-line nuclear orientation (OLNO) involves continuous implantation of unpolarised nuclei which are cooled to milli-Kelvin temperatures by nuclear spin lattice relaxation. Anisotropy of radiation from the cold, polarised nuclei is analysed to yield nuclear moments and decay properties. Incomplete relaxation prior to decay complicates analysis and, as half-lives shorten on moving further from stability, places an ultimate limit on the range of nuclei which can be studied by OLNO. This paper introduces a new method, time resolved on-line nuclear orientation (TR-OLNO) in which the implanted beam is pulsed and study is made of the nuclear relaxation itself to yield nuclear g-factors. Decay scheme parameters can also be extracted when the relaxation is observed. This method has its optimum application as half-life and relaxation time become comparable, thus extending the range of the OLNO technique. The basic principles of the new method are introduced and its application to the study of decay chains of implanted even- and odd-A nuclei is discussed. The ability to deal with “inherited” orientation in a decay sequence is emphasised. Examples are given of existing TR-OLNO studies of light Au isotopes by the NICOLE Collaboration.     

Transverse Image Reconstruction in Tl-201 Myocardial Scans

A commercially available tomographic imaging system has been interfaced to a digital computer in our laboratory. This enables the computer to collect list-mode data which can be reconstructed by backprojection to yield longitudinal and transverse digital tomographic planes. A phantom was scanned and both longitudinal and transverse digital images are shown. A patient study using the myocardial imaging agent Tl-201 was performed, yielding both longitudinal and transverse images of the heart. The problems associated with transverse reconstruction by backprojection are discussed.