NASOPHARYNGEAL CARCINOMA RADIOSENSITIVITY PREDICTION BY CYTOKINESIS－BLOCK MICRONUCLEUS ASSAY

ＮＡＳＯＰＨＡＲＹＮＧＥＡＬ　ＣＡＲＣＩＮＯＭＡ　ＲＡＤＩＯＳＥＮＳＩＴＩＶＩＴＹ　ＰＲＥＤＩＣＴＩＯＮ　ＢＹ　ＣＹＴＯＫＩＮＥＳＩＳ－ＢＬＯＣＫ　ＭＩＣＲＯＮＵＣＬＥＵＳ　ＡＳＳＡＹＹａｎｇＸｉｎｇ（杨星）；ＳｈｉＪｉａｎｈｕｉ（史剑慧）ａｎｄＣｈ...     

BODY SURFACE EXPOSURE DISTRIBUTION OF EXAMINEES RECEIVED UPPER G．I．T．X－RAY EXAMINATION

ＢＯＤＹ　ＳＵＲＦＡＣＥ　ＥＸＰＯＳＵＲＥ　ＤＩＳＴＲＩＢＵＴＩＯＮ　ＯＦ　ＥＸＡＭＩＮＥＥＳ　ＲＥＣＥＩＶＥＤ　ＵＰＰＥＲ　Ｇ．Ｉ．Ｔ．Ｘ－ＲＡＹ　ＥＸＡＭＩＮＡＴＩＯＮＦｅｎｇＤｉｎｇｈｕａ（冯定华）ａｎｄＣｈｅｎｇＱｉｊｕｎ（程祺钧）（Ｆａｃｕ...     

STUDIES ON RADIATION INDUCED CROSSLINKING OF CIS 1，4－POLYBUTADIENE BY ~（13）C NMR

ＳＴＵＤＩＥＳ　ＯＮ　ＲＡＤＩＡＴＩＯＮ　ＩＮＤＵＣＥＤ　ＣＲＯＳＳＬＩＮＫＩＮＧ　ＯＦ　ＣＩＳ　１，４－ＰＯＬＹＢＵＴＡＤＩＥＮＥ　ＢＹ　~（１３）Ｃ　ＮＭＲＺｈａｏＸｉｎ；ＤｕＹｏｕｒｕａｎｄＹｅＣｈａｎｈｕｉ（ＬａｂｏｒａｔｏｒｙｏｆＭａｇｎｅ?..     

STUDY ON BEHAVIOUR OF CR FORMULATION OF THIOBENCANB IN A MODEL PADDY FIE

ＳＴＵＤＹＯＮＢＥＨＡＶＩＯＵＲＯＦＣＲＦＯＲＭＵＬＡＴＩＯＮＯＦＴＨＩＯＢＥＮＣＡＮＢＩＮＡＭＯＤＥＬＰＡＤＤＹＦＩＥＬＤＳｕｎＪｉｎｈｅ（孙锦荷）；ＬｉＸｉｎｇｍｉｎｇ（李兴明）；ＣｈｅｎＺｉｙｕａｎ（陈子元）ａｎｄＺｈａｎｇＱｉｎｚｈｅｎｇ（张...     

DETERMINATION OF SUPERFICAL ABSORBED DOSE FROMEXTERNAL EXPOSURE OF WEAKLY PENETRATING RADEATIONS

ＤＥＴＥＲＭＩＮＡＴＩＯＮＯＦＳＵＰＥＲＦＩＣＡＬＡＢＳＯＲＢＥＤＤＯＳＥＦＲＯＭＥＸＴＥＲＮＡＬＥＸＰＯＳＵＲＥＯＦＷＥＡＫＬＹＰＥＮＥＴＲＡＴＩＮＧＲＡＤＥＡＴＩＯＮＳＣｈｅｎＬｉｓｈｕ（陈丽姝）（ＣｈｉｎａＩｎｓｔｉｔｕｔｅｏｆＡｔｏｍｉｃＥｎ...     

CONCLUSION OF INTERNATIONAL SYMPOSIUM ON NUCLEAR ENERGY AND THE ENVIRONMENT AT BEIJIN ON 14～18 OCT.1996

ＣＯＮＣＬＵＳＩＯＮＯＦＩＮＴＥＲＮＡＴＩＯＮＡＬＳＹＭＰＯＳＩＵＭＯＮＮＵＣＬＥＡＲＥＮＥＲＧＹＡＮＤＴＨＥＥＮＶＩＲＯＮＭＥＮＴＡＴＢＥＩＪＩＮＯＮ１４～１８ＯＣＴ．１９９６Ｂ．Ｇ．Ｂｅｎｎｅｔ（ＵＮＳＣＥＡＲ）Ｗｅｈａｖｅｃｏｍｅｔｏｔｈｅｅｎ...     

RADIOIMMUNOTOXICOLOGICAL EFFECT OF ENRICHED URANIUM ON CENTRAL AND PERIPHERAL IMMUNE CELLS AND THE PROTECTIVE ACTION OF IL－1 AND IL－2

ＲＡＤＩＯＩＭＭＵＮＯＴＯＸＩＣＯＬＯＧＩＣＡＬＥＦＦＥＣＴＯＦＥＮＲＩＣＨＥＤＵＲＡＮＩＵＭＯＮＣＥＮＴＲＡＬＡＮＤＰＥＲＩＰＨＥＲＡＬＩＭＭＵＮＥＣＥＬＬＳＡＮＤＴＨＥＰＲＯＴＥＣＴＩＶＥＡＣＴＩＯＮＯＦＩＬ－１ＡＮＤＩＬ－２￥ＺｈｕＳｈｏｕｐｅ...     

LARGE VOLUME IONIZATION CHAMBER USED AS LABORATORY REFERENCE FOR LOW ENERGY X－RAY MEASUREMENT

ＬＡＲＧＥ　ＶＯＬＵＭＥ　ＩＯＮＩＺＡＴＩＯＮ　ＣＨＡＭＢＥＲ　ＵＳＥＤ　ＡＳ　ＬＡＢＯＲＡＴＯＲＹ　ＲＥＦＥＲＥＮＣＥ　ＦＯＲ　ＬＯＷ　ＥＮＥＲＧＹ　Ｘ－ＲＡＹ　ＭＥＡＳＵＲＥＭＥＮＴＹａｎｇＧｕｏｓｈａｎ；ＸｕｅＹｏｎｇｋｕａｎｄＣａｉＦａｎｇｏ...     

EXTRACTION OF AMERICIUM AND LIGHT RARE EARTHS BY 2－ETHYL HEXYL PHOSPHONIC ACID 2－ETHYL HEXYL ESTER

ＥＸＴＲＡＣＴＩＯＮ　ＯＦ　ＡＭＥＲＩＣＩＵＭ　ＡＮＤ　ＬＩＧＨＴ　ＲＡＲＥ　ＥＡＲＴＨＳ　ＢＹ　２－ＥＴＨＹＬ　ＨＥＸＹＬ　ＰＨＯＳＰＨＯＮＩＣ　ＡＣＩＤ　２－ＥＴＨＹＬ　ＨＥＸＹＬ　ＥＳＴＥＲＺｈｕＹｏｎｇｊｕｎ（朱永）ａｎｄＪｉａｏＲｏｎｇｚｈ...     

A DYNAMIC FOOD CHAIN MODEL FOR HONG KONG BASED ON RADFOOD MODEL AND BIRCHALL－JAMES ALGORITHM

Ａ　ＤＹＮＡＭＩＣ　ＦＯＯＤ　ＣＨＡＩＮ　ＭＯＤＥＬ　ＦＯＲ　ＨＯＮＧ　ＫＯＮＧ　ＢＡＳＥＤ　ＯＮ　ＲＡＤＦＯＯＤ　ＭＯＤＥＬ　ＡＮＤ　ＢＩＲＣＨＡＬＬ－ＪＡＭＥＳ　ＡＬＧＯＲＩＴＨＭＫ．Ｎ．Ｙｕ（余君岳）；Ｋ．Ｐ．Ｎｇ（吴国斌）；Ｔ．Ｃｈｅｕｎｇ（...     

用扫描质子探针与中子活化分析方法研究微量铂赋存状态

用中子活分分析确定四川新街铂矿的矿化特征，用扫描质了探针作铂的微区分布研究。首次在该矿原位找到微米粒度的砷铂矿物。结果表明，新街铂矿为富铂钯型铂矿。微量铂主要以砷铂矿物独立存在。     

Applications of proton and nuclear microprobes in ore deposit mineralogy and metallurgy

The micro-PIXE technique usefully complements the analytical capabilities of the electron microprobe in many investigations of ore deposit mineralogy and metallurgy. Unfortunately, micro-PIXE has not been widely used, largely because of a paucity of accessible proton/nuclear microprobes designed with sample- and data-handling facilities suitable for mineralogical targets.Ore deposit mineralogy studies are performed to achieve a wide range of objectives: from the identification of parameters useful for mineral exploration through an understanding of the genesis of ore deposits to a complete characterization of the minerals, necessary to provide guidance for mineral beneficiation and metal extraction. Trace-element information, to calculate partition coefficients between co-existing minerals, or on fluid inclusions, provides geothermometric data on ore deposits. Dating of mineral deposits can be done by measuring the trace quantities of U, Th and Pb in zircon crystals. Efficient metal extraction depends on knowledge of the mineralogical distribution of elements of economic interest (e.g., Ag, Au, Pt-group) as well as knowledge of those which can contaminate the environment or the efficiency of metallurgical processes (e.g., Se, As).The specific requirements for an ideal proton microprobe for mineral analyses are discussed. In addition, new analytical data are presented for sulphide minerals (troilite and pentlandite), an oxide mineral (chromite), and for copper anodes.     

Micro-SR-XRF and micro-PIXE studies for archaeological gold identification - The case of Carpathian (Transylvanian) gold and of Dacian bracelets

Trace-elements are more significant for provenancing archaeological metallic artifacts than the main components. For gold, the most promising elements are platinum group elements (PGE), Sn, Te, Sb, Hg and Pb. Several small fragments of natural Transylvanian gold - placer and primary - were studied by using micro-PIXE technique at the Legnaro National Laboratory AN2000 microbeam facility, Italy and at the AGLAE accelerator, C2RMF, Paris, France and by using micro synchrotron radiation X-ray fluorescence (micro-SR-XRF) at BESSY synchrotron, Berlin, Germany. The goal of the study was to identify the trace-elements, especially Sn, Sb and Te. A spectacular application to five Dacian gold bracelets authentication is presented (Sn and Sb traces).     

伟晶花岗岩型铀矿石堆浸工艺研究与应用

介绍某低品位伟晶花岗岩型铀矿石矿物特性。研究在混合氧化剂存在条件下的这种难浸矿石的堆浸工艺。500 t半工业结果表明:试验解决了该类型矿石堆浸工艺,达到了工业生产要求的技术指标。     

Nuclear microprobe analysis of brain tissue: Quantitative aspects and concentration variability of minor and trace elements

Specimen mass loss, major element loss, and alterations in minor and trace elements during nuclear microprobe bombardment were studied for various types of human brain tissues. The results were quite similar to those of an earlier study on bovine liver (Van Lierde et al., 1995). Special efforts were made to obtain accurate micro-PIXE concentration data (expressed in μg/g dry weight). This involved determination of the local specimen mass thickness. From a comparison of the micro-PIXE data with the results of macro-PIXE it was concluded that micro-PIXE data with an accuracy of better than 20% can be obtained. The variability in elemental concentrations over various types of brain tissue and within a single tissue type were examined. From a scan over the substantia nigra, it appeared that Fe exhibits a complex concentration pattern in this tissue type.     

基于Micro-PIXE能谱的大气单颗粒物污染源模式识别研究

来自不同排放源的大气气溶胶,其化学组成特别是微量元素组成具有各自的特征,在Micro-PIXE上呈现不同的特征峰。因此单个气溶胶颗粒物的Micro-PIXE能谱特征可作为其指纹,查找污染源。本文提出了适应于Micro-PIXE谱的模式识别算法,并对这种以Micro-PIXE能谱特征溯源的方法进行了可靠性检验。结果表明以此种方法进行源解析具有较高的可信度。相应的模式识别算法具有准确,快速的特点。     

The use of the maximum entropy method for the improvement of the spatial resolution of the micro-PIXE maps

The deconvolution procedure based on the maximum-entropy method is applied to improve both resolution and noise characteristics of micro-PIXE maps. The procedure is simple to execute, fast, easily automated and assumes no a priori information. The best improvement is observed for data with low statistics. Special emphasis is given to the difficulties and limitations of processing micro-PIXE data. Examples of applications for biomedical samples are presented.     

Three-dimensional measurement of elemental distribution in minute samples by combination of in-air micro-PIXE and STIM

A technique of measuring three-dimensional (3D) distribution of trace elements in a minute sample was studied using the in-air micro-PIXE (Particle Induced X-ray Emission) system. A 3D distribution was acquired by means of reconstructing numbers of projection images of the sample obtained by micro-PIXE analyses from different directions. This is basically the same technique as X-ray CT (Computed Tomography). However, when this technique was applied to the in-air micro-PIXE analysis, the X-ray yields should be corrected in taking account of such parameters as the X-ray production cross section, the X-ray attenuation coefficient, the energy of an incident particle, and the 3D densities of major elements in the analysis sample. In this study, STIM (Scanning Transmission Ion Microscopy)-CT was used to obtain the 3D density map of the sample. Corrected 3D distributions of sulfur and iron in a minute test sample were successfully measured with this technique in combination of STIM-CT and in-air micro-PIXE.     

Micro-PIXE study of Ag in digestive glands of a nano-Ag fed arthropod (Porcellio scaber, Isopoda, Crustacea)

Micro-proton induced X-ray emission (micro-PIXE) method was applied to study the micro-localization of silver (Ag) in digestive glands of a terrestrial arthropod (Porcellio scaber) after feeding on silver nanoparticles (nano-Ag) dosed food. The aim of our work was to assess whether feeding on nano-Ag results in the assimilation of silver (Ag) in digestive gland cells. To study micro-localization and elemental distribution of Ag, the animals were fed on food dosed with nanoparticles for 14 days under controlled laboratory conditions. At the end of the feeding exposure, the animals were dissected and digestive glands prepared for micro-PIXE analyses and TEM investigation. The results obtained by micro-PIXE documented high amounts of Ag inside S-cells of the digestive gland epithelium; however, TEM investigation did not show particle aggregates inside digestive gland cells. Also no adverse effect on feeding behavior was recorded what is a measure of toxic effects. We explain the presence of Ag inside the cells as a result of the assimilation of dissoluted Ag ions from ingested nano-Ag particles. Assimilation of excessive amounts of ingested metal ions in S-cells is a well known metal detoxification mechanism in isopods. We discuss the advantages of using micro-PIXE for the micro-localization of elements in biological tissue in studies of interactions between nanoparticles and biological systems.