GIC4117串列加速器外束PIXE/PIGE分析系统

本文介绍在北京师范大学GIC4117串列加速器上建立的外束PIXE/PIGE分析系统,和基于此系统的薄样品外束PIXE/PIGE定量分析方法。给出了2010年Teflon滤膜采集的361个气溶胶样品外束PIXE分析得到的各元素平均探测限和最低探测限,并同真空PIXE分析探测限进行了比较。利用标准样品给出了激发曲线不同坪区薄样品外束PIGE分析F和Na的探测限,通过测定¹⁹F(p, p′γ)¹⁹F激发的197 keV γ射线得到的F的探测限可达73.9 ng•cm^-2,Na的探测限可达198.9 ng•cm^-2。     

福泉山良渚文化玉器的PIXE分析

报道用质子激发X荧光技术（PIXE）分析福泉山良渚文化玉器的实验结果。采用PIXE方法可以可靠地鉴别福泉山玉器的种类,福泉山玉器中有软玉、也有岫玉。它们与江苏溧阳小梅岭玉在元素含量上差别很大,但软玉与新疆和田出产的软玉很类似。分析福泉山软玉铁镁占位比S,可排除杂质元素干扰,得到矿物结构和沁色信息。     

陶瓷样品外束质子荧光定量分析中样品定位精度的研究

通过改变与陶瓷有相似成份的GBW07306水系沉积物标准样品的前后位置和角度,研究了陶瓷样品外束质子荧光(External beam proton induced X-ray emission,外束PIXE)分析中样品位置对测量结果的影响.并以此为依据分析了陶瓷样品外束PIXE定量分析对样品定位精度的要求.结果表明:在质子能量为2.5MeV、样品距离质子引出窗口12mm和质子束入射方向夹角为30°、Si(Li)探测器在80°且距离样品20mm的实验条件下,沿束流方向位置变化引起的相对误差控制在5%以内时,样品定位精确度应高于±0.14mm;样品与质子束夹角变化引起的相对误差控制在5%以内时,样品角度定位需精确到±1.2°.     

样品位置对外束PIXE分析的影响

通过改变标准样品的前后位置和摆放角度,研究样品位置对外束PIXE分析中Ar、Si、Ca、Fe等元素的特征X射线归一化峰面积的影响,并以此为依据分析外束PIXE对样品定位精度的要求。结果表明：为使由样品位置变化引起的相对误差在5%以内,样品摆放位置需精确到±0.14mm;为使由样品角度引起的相对误差在5%以内,样品摆放角度需精确到±1°。     

四川地区出土古玻璃的质子激发X荧光分析

质子激发X荧光(PIXE)技术是一种对古代玻璃的化学成分进行非破坏性分析的有效方法.采用PIXE技术对四川地区出土的战国(770-476 B.C.)和六朝(220-589 A.D.)时期古玻璃的化学成分进行了定量测定.结果表明:战国时期的玻璃璧和蜻蜓眼玻璃珠均属于PbO-BaO-SiO2玻璃,从成分和外型特征看,这些样品都为中国自制;而六朝时期的耳珰、玻璃珠的化学成分呈现多样性,有K2O-CaO-SiO2玻璃、K2O-SiO2玻璃等.结合实验和文献结果,对中国古玻璃技术传播的相关问题进行了讨论.     

铍中主要杂质元素的INAA和PIXE测定

对铍中金属杂质元素的测定,INAA和PIXE分析是非常有利的方法。它具有灵敏度高、可靠性好、多元素同时测定、操作简便等优点。PIXE分析是利用静电加速器提供的2MeV质子束,流强100nA,轰击1000秒,测量X射线的Si(Li)半导体探测器的能     

扬州西汉墓出土古玻璃的质子激发X荧光分析

化学成分分析是中国古代玻璃研究中一个重要方面，可以为研究中国古代玻璃的起源和技术发展等提供科学的依据，有必要发展新的测试方法。质子激发X荧光(PIXE)技术是一种高灵敏度、非破坏性、多元素定量测定的分析方法。采用PIXE技术对扬州西汉墓出土的玻璃衣片进行了定量分析。结果表明：这些玻璃属中国自创的PbO-BaO-Si02系玻璃；衣片由中心玻璃层和厚度不等的表面腐蚀层组成；腐蚀层比玻璃层含有相对较高的PbO、P2O5和CaO，而BaO和SiO2的含量则比玻璃层大大降低。对实验结果进行了讨论。     

PIXE研究的进展

本文介绍第四届国际PIXE会议上关于PIXE的应用开发和研究进展的情况,PIXE在环境科学、生物医学、材料、地质、考古以及其它领域得到广泛开发利用,与此同时,PIXE在方法学和技术方面也在不断改进。     

广西合浦地区出土汉代古玻璃的质子激发X荧光分析

采用改进的外束质子激发X射线荧光、电感耦合等离子体原子发射光谱分析等技术,对广西合浦地区出土的一批汉代古玻璃样品的化学成分和结构特性等进行了检测.结果表明:两汉时期,合浦地区的古代玻璃存在K2O-SiO2、PbO-BaO-SiO2、PbO-SiO2、Na2O-K2O-PbO-SiO2、(Na2O)K2O-CaO-SiO2等多种类型,但绝大多数为K2O-SiO2玻璃.表面风化可引起K2O-SiO2玻璃表面K2O等助熔剂的流失和富硅层的形成.综合化学成分以及器型特征,认为我国汉代K2O-SiO2玻璃制造技术可能受到同时期PbO-BaO-SiO2玻璃制造技术和外来技术的双重影响.     

掠入射质子荧光分析技术研究

首次提出采用掠入射质子荧光分析(PIXE)方法对表面存在污染的铝片、注入铁离子的单晶硅片以及注入氧隔离SOI半导体材料进行了分析.实验结果表明,现有PIXE分析技术不需要对设备做任何重大的升级改造,只是简单的采用掠入射方法,就能有效提高其表面分析的灵敏度.通过研究不同角度时峰面积与探测限之比与穿透深度之间的关系,得出质子柬在样品中的穿透深度越浅,峰面积与探测限的比值就越大,可检测的表面污染的灵敏度就越高.     

用质子激发X荧光分析技术鉴别玉器种类

质子激发Ｘ荧光分析中以测定玉器的主量、次量及微量元素的成分和含量,因而可以将那些外形及颜色相近的玉器因其化学组分的不同而清楚地分开,并得知其真实的材料种类。对于主要化学组分一致的同类玉器,如果产于不同的地方,则由于其成矿地区地球化学环境的不同,它们的微量元素种类及含量也将有所不同,因而这一方法也可用来判定玉器的产地。     

河南南阳独山玉的PIXE研究

利用质子激发Ｘ荧光分析,湿法化学分析对河南南阳独山玉进行常量和微量元素分析,确定了鉴定独山玉的指纹元素,为建立无损鉴定古玉器的方法提供卫一条重要途径。     

PIXE study on Chinese underglaze-red porcelain made in Yuan Dynasty

In China. the firing and glazed red techniques of producing underglaze-red porcelain began early in the Yuan Dynasty (AD1206-1368). This paper reports the results of the PIXE analysis of ancient Chinese underglaze-red porcelain produced at Kuan kiln (Jingdezhen, Jiangxi Province) in the Yuan Dynasty. In this work the elemental composition analysis of the obtained samples was carried out using the PIXE facility of a 3 MeV tandem accelerator at Fudan University. The major, minor and trace elements of the clay body, white and red glazes were determined,and details of the results are presented. The obtained data can be used for identification of precious Chinese Yuan underglaze-red porcelain,     

Trace element analysis of blood samples from mentally challenged children by PIXE

The accelerator based ion beam analysis method of proton induced X-ray emission (PIXE) has been used for analysing up to 14 elements in the blood serum of patients, collected from rehabilitation centres for the mentally retarded and from Medical College Hospital, Coimbatore, Tamil Nadu, India. The experimental subjects of the different groups displayed significant variations in their levels of certain trace elements such as zinc, iron, copper, phosphorus, chlorine, and rubidium. The results are compared with those of healthy control subjects and are discussed in detail in this paper. Hence, PIXE as a method of trace element analysis can be used to determine trace element content in mentally challenged patients.     

质子非卢瑟福背散射测量气溶胶样品中氢、碳、氮和氧的含量

气溶胶样品中Z＞12以上元素含量的质子荧光(PIXE)分析是北京师范大学GIC4117串列加速器的主要应用领域之一。为弥补PIXE无法分析H、C、N和O等轻元素之不足，在PIXE靶室160°散射角安装金硅面垒探测器，用质子非卢瑟福背散射分析（PNBS）方法对核孔膜采集的气溶胶样品中H、C、N和O等轻元素的含量进行测量。测量得到的气溶胶样品中H和Si元素含量与质子前角散射（PESA）和PIXE的分析结果相近，表明PNBS可用于核孔膜采集的气溶胶样品的分析。     

Forensic analysis of tempered sheet glass by particle induced X-ray emission (PIXE)

The elemental concentrations of five trace elements in tempered sheet glass fragments were determined using particle-induced X-ray emission (PIXE) spectrometry. The trace element concentrations for calcium, iron, manganese, strontium, and titanium are compared to those obtained by inductively-coupled plasma-atomic emission spectrometry (ICP-AES) following complete digestion by hydrofluoric acid. For these five elements, the absolute concentrations obtained by both methods are shown to agree well over a wide range of concentrations. The limits of detection for trace elements are typically lower for the ICP-AES method. However, we show that the concentrations of these five elements can be accurately measured by the PIXE method. Since PIXE is an entirely non-destructive method, there exists a niche for this technique to be used as a complement to the more sensitive ICP-AES technique in the forensic analysis of sheet glass.     

Elemental analysis of limestone samples from Ewekoro limestone deposit in southwest Nigeria

Limestone samples of different colours from Ewekoro limestone deposit in Ogun State, Nigeria were subjected to elemental analysis by proton-induced X-ray emission (PIXE) and proton-induced gamma-ray emission (PIGME) techniques. The irradiation was by 2.5 MeV proton beams from the ion beam analysis (IBA) facility of the 3 MV Van de Graaff accelerator at the Australian Nuclear Science and Technology Organisation (ANSTO), Lucas Heights. Elemental composition and concentrations of 22 major, minor and trace elements were determined. The NIST geological standard, NBS278, was analysed for quality assurance. The concentrations of the major elements (Ca, Fe, K and Al) are similar in the samples while the other major elements differed. Calcium accounts for about 38%, giving 86.8% CaCO₃ content in the limestones. The major elements (Al, Ca, Fe, Si, S and K), present in the limestones, were also found to be enriched in airborne particulate matter studied by earlier workers, thus confirming cement dust as the major contributor to the particulate matter within and around cement factories.     

Some aspects of statistical distribution of trace element concentrations in biomedical samples

Concentrations of trace elements in biomedical samples were studied using X-ray fluorescence (XRF), total reflection X-ray fluorescence (TRXRF) and particle-induced X-ray emission (PIXE) methods. Used analytical methods were compared in terms of their detection limits and applicability for studying the trace elements in large populations of biomedical samples. In a result, the XRF and TRXRF methods were selected to be used for the trace element concentration measurements in the urine and woman full-term placenta samples. The measured trace element concentration distributions were found to be strongly asymmetric and described by the logarithmic–normal distribution. Such a distribution is expected for the random sequential process, which realistically models a level of trace elements in studied biomedical samples. The importance and consequences of this finding are discussed, especially in the context of comparison of the concentration measurements in different populations of biomedical samples.     

用质子激发X荧光分析法测定肝硬化病人血清的微量元素含量——探讨中医治疗疗效

本文利用质子激发经X荧光分析法测量正常人和肝硬化病人血清中Zn、Cu、Fe、Br和Rb等元素的含量。结果表明,中医治疗前后,血清中微量元素含量有显著差异。治疗后,病人症状有明显改善,且微量元素的含量也向正常人靠近。