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1.
Proton induced X-ray emission (PIXE) technique and factor analysis were used to study the recovery of making-technology of Chinese Longquan celadon made in the late Southern Song Dynasty (1127–1279 CE). Based on factor analysis, for the raw material for body and the recipe for glaze, there is a close but slightly different relationship between these Longquan celadons unearthed from the core area of Dayao and the non-core area, despite all the Longquan celadons belong to the high-calcium-glaze system. The chemical compositions of most of the tentative body and glaze samples are very close to those of Longquan celadons unearthed from the core area of Dayao and the non-core area. This study can provide a guidance for recovery of making-technology of Longquan celandon.  相似文献   
2.
A technique for measuring optical dot gain, i.e. the relative difference between the actual screen dot and the optically perceived one, is presented. By combining measurements from the non-optical nuclear microprobe with data from image analyzing technique the optical dot gain can be determined. The procedure to reach pixel by pixel correlation on a micrometer scale is discussed. In the newsprint sample studied in this investigation a typical optical dot gain between 15 and 20% was deduced. The variation in the optical dot gain was correlated with other characteristic parameters of the print and newsprint and especially a positive correlation to the mass density of the newsprint was observed.  相似文献   
3.
用质子激发X荧光分析法测定48只家兔在挠骨骨折愈合过程中骨骼中多种微量元素含量的变化。结果表明,Fe和Sr分别呈鼓凸形和下凹形规律性变化,故Fe和Sr含量的变化可作为骨折愈合过程的指示剂。在骨折愈合过程中发现骨骼和血液中元素钙的相对含量保持不变,故无法为西医用补充钙来治疗骨折的疗法提供依据,但我们的研究结果却表明中医补充微量元素治疗骨折的疗法是有道理的。  相似文献   
4.
头发是人体排泄微量元素的器官之一,头发中微量元素的含量间接地反映人体中微量元素的含量。头发中微量元素的含量能反映一定时间内人体微量元素含量的情况。它可以作为环境条件和人体功能的“指示器”,给出环境污染和人体健康与疾病的信息。而发样又  相似文献   
5.
用质子激发X射线分析方法进行人发微量元素的分析研究   总被引:1,自引:0,他引:1  
一、序言 质子激发X射线分析方法是瑞典人约翰逊在1970年首先提出来的。由于它具有灵敏度高、取样少、无损伤、快速、适用范围广等特点,使它在十余年中在生物医学、环境科学、地质、冶金、考古学和法学等领域得到了广泛的应用。我们应用质子激发X射线分析方法分析了人发中的微量元素。  相似文献   
6.
X‐ray absorption near edge structure (XANES) spectroscopy at the P K‐edge was used to monitor ZDDP antiwear film thickness with rubbing time. Thermal immersion films of varying thickness were generated from the ZDDP and analysed using XANES spectroscopy and the particle induced X‐ray emission (PIXE) technique. P K‐edge XANES edge jumps and (1s → np) peak heights of the spectra were plotted against PIXE mass thickness values in order to establish calibration curves. Antiwear films were analysed using XANES spectroscopy, and average mass thicknesses were extrapolated from the calibration curves. A set of antiwear films formed in the presence of ZDDP and then further rubbed in base oil (no ZDDP) showed no significant decrease in film thickness. A set of antiwear films rubbed in the presence of ZDDP for various lengths of time showed an increase in film thickness, followed by thinning of the film. The decrease in film thickness is believed to be due to wear caused by the ZDDP solution decomposition products acting as an abrasive in the contact region. This revised version was published online in July 2006 with corrections to the Cover Date.  相似文献   
7.
Abstract

The prerequisite for bioactive glasses to bond to living bone is the formation of biologically active apatites on their surface in the body. Reactions and bioactivity mechanisms between bioactive glasses and bone depend on the glass composition. We study a glass in the SiO2‐Na2O‐CaO‐P2O5‐K2O‐Al2O3‐MgO system. To characterise physicochemical reactions at the materials periphery, we immersed the glass pastilles into biological fluids for periods of 5, 10, and 20 days. The surface changes were studied at the micrometer scale by a Particle Induced X‐ray Emission (PIXE) method associated with Rutherford Backscattering Spectroscopy (RBS). After 20 days of immersion, elemental maps showed the formation of a calcium‐phosphate layer at the surface of the glass pastilles. The thickness of this layer was around 15 µm. Thanks to the PIXE method, we demonstrated the presence of traces of Mg in this layer. The glass doped with MgO leads to the formation of an apatite which incorporates magnesium. Formation of this Ca‐P‐Mg layer represents the bioactive properties of the studied glass. This biologically active layer improves the properties of the glass and will permit a chemical bond between the ceramic and bone.  相似文献   
8.
Particle induced X-ray emission, particle induced γ-ray emission studies has been carried out to analyse normal and carcinoma tissues and blood samples of gallbladder of both sexes and seventeen trace elements namely Na, Mg, Al, K, Ca, Ti, Cr, Mn, Fe, Co, Ni, Cu, Zn, As, Se, Br and Pb were estimated in the tissue and blood samples. In the present study, concentration of Zn in the carcinoma gallbladder tissue is less than that of the normal gallbladder tissue. Tobacco habit could be one of the important factors to decrease the elemental concentrations in blood and tissue samples.  相似文献   
9.
We have developed the two-dimensional mapping technique with in-air-PIXE (2D-PIXE) using a metal capillary as a guide to extract ion beam to air. The metal capillary is the conventional injection needle with a 200 μm inside diameter. For the target which is the character made of the copper wires on aluminum basement, 2D-PIXE measurements were performed by irradiating 3 MeV proton beam. As a result, the character was tend to be restored clearly by this method. We discuss about the result of the two-dimensional map from a viewpoint of the signal-to-noise ratio and the resolution. This technique is expected to be applicable to various fields such as biology, nano-technology, archeology and so on.  相似文献   
10.
用X射线荧光分析法对珍贵邮票进行快速鉴定的技术   总被引:4,自引:0,他引:4  
在有关邮票鉴定实验结果的基础上,编写了X射线荧光分析技术对珍贵邮票快速鉴定的在线分析程序,该程序将测量,数据获取,判别分析,邮票数据库调整等工作集中在一起,在测量的同时可完成数据获取和判别分析等工作,使得分析判别工作在测量过程中完成,并将判别结果及时反馈,以便测量者决定测量工作的进行与否,使鉴定结果在尽可能短的时间内给出,从而使得鉴定技术趋于实用化。  相似文献   
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