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1.
介绍了一种用于扫描质子微探针分析的大气气溶胶单颗粒样品的制备方法。通过实验摸索出一种适合于支撑颗粒物的材料聚乙烯醇缩丁醛(PVB)。大气颗粒物被直接采集在PVB薄膜上从而制成样品,保持了颗粒物的原始信息。用显微镜观察了采集的颗粒物,颗粒物之间完全分开,颗粒物间距合适。样品的扫描质子微探针试验结果表明,所制成的单颗粒样品能经受住质子束的长久轰击。对PVB薄膜的本底测试表明,这种膜的本底很小,不会对被测颗粒物的元素产生干扰。  相似文献   

2.
沙因  谷英梅 《核技术》1996,19(4):229-232
把用安德联撞击采样器获得的空气动力学直径7-11μm的气溶胶粒子镶嵌在PVDF薄膜内,用扫描质子微探针方法对在180μm×150μm范围内一群单个气溶胶粒子中12种元素的含量进行了微区分析,用三维等高线法给出了一群单溶胶粒子中12种元素的两维分布,并对采样地区的大气污染来源进行了较深入的分析,为大气污染研究提供了新方法。  相似文献   

3.
核子微探针多站多参量数据系统包括由SUN工作站和VME计算机总线组成的系统硬件,以及数据获取和分析软件。基于新的数据系统用Micro-PIXE和Micro-RBS分析了单颗粒大气飞灰,得到了含Pb的单颗粒大气飞灰元素图谱。  相似文献   

4.
用核分析技术研究上海市空气和水环境污染   总被引:3,自引:0,他引:3  
张桂林 《核技术》2001,24(9):727-733
用扫描质子微探针对上海市中心区和若干排放大气气溶胶单颗粒的质子激发X射线能谱进行了测量和形貌分析,然后用人工神经网络计算机识别技术追踪市中心区污染的来源,确定各排放源对它的贡献;用穆斯堡尔效应研究了市中心高架桥和隧道内含铁大气气溶胶颗粒的铁化学形态、尺寸和浓度,以及使用低本底放射性测量技术研究了苏州河水的α、β放射性强度。  相似文献   

5.
本文用高分辨率、高灵敏度的扫描质子微探针(SPM)对鸡胚前脑神经元细胞和骨骼肌肌管细胞中的数量元素进行分析,研究了这两种不同细胞对Zn离子的吸收情况、细胞中元素的相关关系以及微量元素在细胞内的分布情况。结果发现,鸡胚前脑神经元细胞对Zn离子的吸收能力明显大于骨骼肌肌管细胞;并且细胞中Cr、Fe、Ni等微量元素的浓度含量明显偏高;细胞中S-Zn、Fe-Zn等元素呈正相关关系,而P-Ni、Cr-Fe则呈负相关关系。从细胞的元素分布图上还发现不同元素在细胞各个组成部分的含量是不同的,如P、S、K等元素在细胞膜上的含量明显高于其在细胞内的含量。  相似文献   

6.
SPM analysis on groups of single aerosol particles around steel plant   总被引:1,自引:0,他引:1  
Several methods for preparing samples of dispersed single aeroslo particles used in scanning proton microprobe(SPM) analysis were tested.Many elements such as Al,Si,S,Cl,Ca,Ti,Cr,Mn,Fe,Ni,Cu and Zn in the groups of different single aerosol particles from the Capital Steel Plant area were analyzed by SPM,The distributions of elemental contents in the group of single particles were mapped with three dimensional contour and the isometric.A new approach to study the group of different single aerosol particles for air pollution is developed in the present work.The results are significant to assessing the environmental impact of the dispersed single aerosol particles.  相似文献   

7.
A nuclear microprobe with high spatial resolution and high analytical sensitivity was applied to analyze trace elements,especially lead,in vehicle exhaust of Shanghai city.The result shows that the chemical composition and its corresponding x-ray relative intensity are different among different vehicle exhausts.There are many kinds of metal elements in particles of vehicle exhaust.most are harmful to people,such as Ti,Cr,Mn,Pb,etc.We found that the lead concentration was 6820μg/g and the bromine concentration was 5300μg/g in the exhaust from Santana using leaded gasoline(SULG).which is higher than any other kinds of vehicle exhausts.We have also detected the minimum lead in the particles of unleaded gasoline and its content varies from one to another.Its mean concentration was 450μg/g and the highest reached 6210μg/g.The unleaded gasoline‘s Pb existed in the whole particle while the leaded gasoline‘s enriched in the surface of the particle and was more harmful to the human beings.  相似文献   

8.
章净霞  姚惠英 《核技术》1994,17(3):158-163
应用同步辐射X荧光微探针(SR-XMF)和扫描质子微探针(SPM)技术研究了基础医学领域中与微量元素有关的几个课题。初步实验结果表明,具有高灵敏度、高分辨率和对样品损伤小的SR-XMF和SPM技术特别适合于元素含量低的细胞和生物组织样品,这些技术是研究元素的细胞生理学,从细胞水平探讨微量元素的生物学作用机理以及从微观角度阐明疾病的致病机理等方面有独特作用的新手段。  相似文献   

9.
概述了大、中型托卡马克在D-D和D-T运行条件下聚变中子能谱和强度的测量的最新方法;推介了几种最新的聚变中子探测器和能谱仪及活化分析方法;评估了各种聚变中子探测器和能谱仪的优势,适用的范围和技术方面的局限性。对即将建成的HL-2A(中环流器二号A型)托卡马克的聚变中子的泄漏能谱和辐射强度的时、空分辨测量以及研究聚变中子在通过中子倍增剂过程中的能谱变化,在探测器方面提供了几种可供选择的技术方案。  相似文献   

10.
孙斌  孟纪群 《辐射防护》2017,37(3):200-205
采用TRPO萃取—单酰胺(NA)反萃—电沉积制源,以α谱仪测定237Np、239+240Pu、241Am、244Cm等常见核素的活度。该方法在事故应急监测以及液态流出物监测中,对低放废液中上述主要α核素的定性识别和定量分析有较好的应用。  相似文献   

11.
一、14C年代测定单板机的功能1.数据处理 1)被测样品的在线数据处理 14C年代测量时间较长,一般一个样品要测够1000分钟,每10分钟为一段,测量到预置的时间后,单板机就用“3σ”作判据对各段计数进行统计检验,对偏离值超过“3σ”的数据可剔除掉,若要求测量时间一致,还可再补充新的测量值,经过剔除和补充后,将得到“σ1”值,再用“3σ1”作判据,重新进行统计检验,直至全部偏离值没有超过“3σn”为止。仪器及电网负载工作状态正常时,偏离值超过“3σn”的机率只有3‰,所以一般不需要剔除和补充。当测量结束时,打印机打出样品的平均计数率、标准误差、试验误  相似文献   

12.
A noise measurement in the Swedish Ringhals-2 PWR was performed in January 2002 by using twelve gamma-thermometers and two in-core neutron detectors, all located on the same axial level in the reactor. The gamma-thermometers are very versatile tools since they allow estimating the core-averaged moderator temperature noise throughout the core. This core-averaged temperature noise was then used to estimate the MTC by noise analysis, via a new MTC noise estimator. It was shown that whatever the location of the neutron detector might be, the MTC is always correctly estimated by this new MTC noise estimator, without any calibration to a known value of the MTC prior to the noise measurement. For the purpose of comparisons, the MTC was also estimated by using a single gamma-thermomemeter and a single core-exit thermocouple, together with an in-core neutron detector. In such cases, the MTC was systematically underestimated, with a stronger bias for the core-exit thermocouple than for the gamma-thermometer. This shows that the main reason of the MTC underestimation by noise analysis in all the experimental work until now was due to the radially non-homogeneous temperature noise throughout the core. The resulting deviation from point-kinetics of the reactor response has a negligible effect.  相似文献   

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