人发中微量元素与某些呼吸系统疾病关系的研究

用仪器中子活化法测定了正常人和慢性支气管炎,肺气肿,肺心病患者头发中Ｃａ,Ｍｇ,Ｆｅ,Ｓｅ,Ｃｕ,Ｚｎ等１９种元素的含量。测得患者发中Ｃａ,Ｍｇ含量低于正常人,Ｆｅ,Ａｓ,Ｃｏ等含量高于正常人;慢性支气管炎急发期患者发中Ｃａ,Ｍｇ含量低于缓解期患者,Ｆｅ含量高于缓解期患者,均有显著性差异（Ｐ＜０．０５－０．０１）。人发Ｃａ与Ｍｇ呈高度正相关（Ｐ＜０．００１）。还测定了用于治疗慢性支气管炎的中药“咳     

用PIXE技术分析山东省胃癌高,低发区饮水中的微量元素

介绍了用ＰＩＸＥ技术分析饮水中微量元素的方法，给出了山东省胃癌高发区栖霞县与低发区苍山县饮水中的微量元素谱。两地饮水中微量元素含量的检验显示，Ｔｉ，Ｖ，Ｃｕ，Ｆｅ和Ｆｒ等５种元素栖霞均显著高于苍山县。     

EDXRF法测定人发中Ca,Fe,Cu和Zn的含量

本文介绍了国产管激发能量色散Ｘ射线荧光分析仪同时测定人发中Ｃａ、Ｆｅ、Ｃｕ和Ｚｎ的分析方法。该方法采用在人发样品中加入内标元素Ｙ，用化学法溶解人发，制成分析试样，用Ｘ射线荧光分析仪测定试样中的上述元素。此方法对这４种元素的检测限依次为７×ｌ０￣（－６）、ｌ×１０￣（－６）、４×１０￣（－６）和３×１０￣（－６），其变异系数分别为６％、ｌ％、２％和２％。     

用计算机模式识别法和PIXE法研究人发中元素在食管癌诊断中的作用

用ＰＩＸＥ方法对华北地区的４１４例食管癌、食管上皮重度增生病人和正常人的头发样品中的１２种元素进行了测定。经过ｔ检验发现，癌症病人与正常人比较，１０种元素（Ｓｉ，Ｓ，Ｃａ，Ｃｒ，Ｍｎ，Ｆｅ，Ｎｉ，Ｃｕ，Ｐｂ，Ｓｒ）有显著差异；食管上皮重度增生病人和正常人比较，９种元素（Ｓｉ，Ｐ，Ｓ，Ｃａ，Ｃｒ，Ｍｎ，Ｆｅ，Ｎｉ，Ｚｎ）有显著差异，说明头发中微量元素的变化先于人体内食管的癌变。用计算机模式识别法对上     

用INAA法和ICP-MS法对蚯蚓样品作多元素测定比较

用仪器中子活化分析方法对６例蚯蚓样品进行了Ａｓ、Ｂａ、Ｃｄ、Ｃｏ、Ｃｒ、Ｃｕ、Ｆｅ、Ｍｎ、Ｈｇ、Ｒｂ、Ｓｂ、Ｓｅ和Ｚｎ的元素含量测定,并用等离子质谱分析方法和人发标准参考物质进行了比较和核对。结果表明,两种测定方法分析结果相符,大多数元素的相对偏差在±２０％以内。     

放射性铈在模拟水稻田中的行为

研究了１４１Ｃｅ在模拟水稻田中的迁移、积累和分布。结果表明，１４１Ｃｅ进入田水后向土壤和水稻迁移，水中１４１Ｃｅ浓度迅速下降。水稻中１４１Ｃｅ浓度显著地高于土壤和田水。田水和土壤中的１４１Ｃｅ浓度随时间延长基本上单调降低，而水稻中１４１Ｃｅ浓度则在经历某一最大值后便下降。土壤对１４１Ｃｅ的吸附迅速，吸附率较高，９５％以上的１４１Ｃｅ滞留于表层４ｃｍ之内；土壤中１４１Ｃｅ浓度与离表面深度呈单项指数负相关。     

用Monte—Carlo模拟计算中子源在媒介质中的中子注量率分布

本文简单叙述了利用中子感性瞬发γ射线进行物料分析的原理和方法，针对其中的问题对＾２４１Ａｍ－Ｂｅ和＾２２２Ｃｆ中子源在煤介质中的中子注量分布进行了模拟计算，并给出了比较结果和结论。     

眼晶体中某些元素含量与白内障关系的研究

用中子活化分析法测定了正常人眼晶体及老年性白内障晶体中的Ｋ、Ｃａ、Ｎａ、ＣＩ、Ｓ、Ｓｅ、Ｚｎ、Ｍｇ、Ｆｅ、Ｒｂ、Ｃｓ、Ｃｒ、Ｃｏ、Ｃｅ、Ｍｎ、Ｓｂ、Ｓｃ、Ｅｕ和Ｔｈ等１９种元素的含量，发现在白内障晶体中Ｃａ、Ｎａ、Ｃｌ、Ｅｕ、Ｓｂ、Ｆｅ等元素含量显著高于正常晶体；Ｋ、Ｒｂ、Ｃｓ、Ｃｒ、Ｍｎ、Ｃｏ、Ｓｃ和Ｃｅ等元素含量显著低于正常晶体。其中Ｎａ、Ｃｌ、Ｃａ之间；Ｋ、Ｒｂ、Ｃｓ之间存在显著性正相关。Ｎ     

山东省胃癌高低发生地区主要食物中微量元素的PIXE分析

介绍了用ＰＩＸＥ技术分析食物中微量元素的方法,给出了山东省胃癌高发区栖霞县和低发区苍山县当地产主要食物的微量元素谱。ｔ检验结果显示,栖霞县食物中Ｓｒ、Ｎｉ、Ｃｕ、Ｍｎ和Ｆｅ的含量显著高于苍山县,而Ｓｅ的含量则相反。     

不同甲状腺激素水平病人红细胞中的微量元素

用质子激发Ｘ荧光和中子活化分析方法测量了不同甲状腺激素水平的甲状腺病人红细胞中的微量元素Ｋ,Ｃａ,Ｆｅ,Ｃｕ,Ｚｎ,Ｓｅ和Ｒｂ等的含量。用ＳＰＳＳ／ＰＣ软件中的单因素方差分析和相关性分析检验了不同组之间甲状腺激素和微量元素的差异和相关性。结果表明,不同甲状腺激素水平病人红细胞中Ｓｅ元素含量未见显著性差异。     

铀尾矿废渣回填治理区植物中铀放射性水平调查

为了解北方某铀矿尾渣回填区内放射性核素铀在植物体中富集情况,为进一步探讨利用植物修复技术对铀矿区进行土壤修复的可行性,以及寻找放射性核素污染土壤治理的方法提供理论依据,采集矿区内堆浸工位与矿区外尾渣回填治理区常见植物样本,采用ICP-MS测定植物和土壤中放射性铀水平,针对植物对铀的耐受性和富集能力进行评估,筛选出富集能力较强的植物,进一步探索利用植物修复技术对放射性废物治理。结果表明,经对采集的植物中铀含量检测发现植物的地下部分铀含量高于地上部分,铀主要集中在根部,植物各部位铀含量由高到低分别为根、叶、茎。矿区内堆浸工位处的大籽蒿根部铀活度为 64.26 Bq/kg;在矿区外尾渣回填区同一植物根部铀活度为0.86 Bq/kg。所调查的北方某铀矿尾渣回填区内所采集的植物中铀含量极低,远小于矿区内堆浸工位所采植物样品中铀含量。深埋回填铀矿尾渣是切实有效可行的。     

碳化硅探测器的最大线性电流研究

本文研究了电流型碳化硅探测器的最大线性电流特性,给出了最大线性电流计算方法,分析了辐射类型、灵敏区面积、灵敏区厚度和耗尽区电场强度对最大线性电流的影响,利用强脉冲X射线加速器和紫外激光源实验研究了碳化硅探测器的最大线性电流特性。研究结果表明,灵敏区面积4 cm2的碳化硅探测器可获得4 A以上的线性电流,不同规格碳化硅探测器最大线性电流的理论和实验结果最大相对偏差约23%。     

PET detector using waveshifting optical fibers and microchannelplate PMT with delay line readout

We are developing a positron emission tomography (PET) detector with depth of interaction (DOI) sensitivity for breast and small animal imaging. The detector uses layers of high density scintillators sandwiched between orthogonal ribbons of wavelength shifting optical fibers. The fibers are coupled to microchannel plate (MCP)-based position sensitive photomultiplier tubes (PSPMTs) containing a crossed delay line readout anode. Preliminary measurements have been made using blue-green waveshifting fiber ribbons coupled to Lu₂(SiO₄)O:Ce (LSO). The measured photoelectron yield due to wavelength shifted light from the fibers is sufficient to ensure a Poisson probability of only 1.0% that no photoelectron is generated in a given MCP PSPMT. Measurement of internally reflected scintillation light permits energy resolution of better than 25% at 511 keV. Optical fiber readout of high density inorganic crystals provides a significantly larger detective area per unit phototube area than do one-to-one coupling schemes using PSPMTs. With its ability to accurately image single photons, the MCP PSPMT solves problems that have prevented other types of PSPMTs from being used in such a configuration, namely poor resolution at the low light output level of the optical fibers     

山东省胃癌高低发地区主要食物中微量元素的PIXE分析

介绍了用PIXE技术分析食物中微量元素的方法,给出了山东省胃癌高发区栖霞县和低发区苍山县当地产主要食物的微量元素谱．t检验结果显示,栖霞县食物中Sr、Ni、Cu、Mn和Fe的含量显著高于苍山县,而Se的含量则相反．     

EDXRF方法在土壤重金属污染评价中的应用

高灵敏度CUT-3000型能量色散X射线荧光(EDXRF)分析仪采用低能X光管和同位素源双激发方式，以电致冷半导体探测器作为探测系统，使该分析仪具有分辨率高、检出限低、分析元素多的特点。采用该仪器成功地分析了攀枝花地区土壤中重金属的含量，评价了该区土壤重金属污染的特征，结果表明该区重金属污染主要与工矿活动有关。     

Analysis of Contour Map of Natural Radiation in Japan

Natural background radiation in Japan was analyzed based on surveyed data which were rearranged from macroscopic points of view. The background levels were classified into seventeen groups from which a contour map was made by simple interpolations. The general pattern obtained showed that high levels are prominent in Hida Mountains-Wakasa Bay area and Joetsu-northern Kanto provinces, and low levels are prominent in Hokkaido and northern Tohoku districts along with Kanto Plain. The whole area was further divided into two classes according to whether the level is higher than the country-wide mean level. A boundary between the two classes seen in Chubu District was found almost exactly coincides with Itoigawa-Shizuoka Tectonic Line. Kanto Mountainland was found to have higher levels than its neighborhood, which supports the current idea that old geology of granitic rocks gives high level radiation. A good correspondence could be seen between the radiation contours and every tectonic line proposed as the eastern border of Fossa Magna which is important in the tectonics of Japan Islands. It was then anticipated that informations of the natural radiation will give valuable side evidences to infer the geologic history of Japan Islands.     

A proposal for an aseismic design method of equipment and piping for NPPs in a low seismicity area

Recently a regulatory code for an aseismic design of high-pressure gas facilities became effective by the order of the Ministry of International Trade and Industry (MITI) in Japan. This order includes details of the aseismic design of vessels whose “factor of importance” are relatively lower than Class A (Class I) items in nuclear power plants.The author develops his idea on an aseismic design method of equipment and piping of nuclear power plants in a Low Seismicity Area (LSA) based on his experience of the new code for petro-chemical industries and oil refinaries pertaining to high pressure gas facilities mentioned above.The definition of LSA is usually the area whose maximum intensity has never exceeded MMI VI or VII. However, there are two types of LSA, one is really such a low seismicity area, and the other type is the area which has the possibility of stronger earthquake occurrence than those mentioned above, even though it is low. One of the typical examples is the area subjected to “New Madrid Earthquake-1812”. The author develops his concept along these two lines.He briefly describes the new code for high-pressure gas facilities in Japan. This code describes the design methodology of both types of aseismic design analysis, that is, rather sophisticated dynamic methods for facilities whose potential hazard is as high as those in a nuclear power plant, such as liquified chlorine gas storage, and simplified dynamic and static methods for most of the equipment and vessels in those plants. One of the features of this code is the use of design formulae and charts to simplify their design procedure as well as the set of specific computer codes by the MITI. These computer codes are prepared by the MITI or approved by the MITI for providing equivalent capability to the practice designated in the MITI order.The author's philosophy for the code of equipment and pipings in LSA is that they must be as simple as possible, and most of the analytical work for the design should be eliminated, or at least limit the use of simplified methods, such as the static seismic coefficient method or the modified seismic coefficient method with a simplified response spectrum. The use of general design criteria or a guideline of structural details may be better than a sophisticated design analysis as a result.     

Dose and Dose Rate Dependence of 8080a Microprocessor Failures

The occurrence of transient upset and catastrophic failure in 8080A microprocessors was investigated over a dose-rate range of 6 × 10-4 to 3 × 10+10 rads/sec. The transient upset and catastrophic failure levels depended on both dose and dose-rate. For example, the dose at which catastrophic failure occurs is 10 times greater at the highest dose-rates investigated than at the lowest. Irradiation was performed using both low energy (45 kV x-ray tube, 200 kV flash x-ray source) and high energy (Co 60, Linac) sources. The observed transient upset and catastrophic failure levels were significantly higher for low energy irradiation than for high energy irradiation. These results have important implications for models of ionizing radiation effects in MOS devices.     

Analyses on the Ionization Instability of Non-Equilibrium Seeded Plasma in an MHD Generator

Recently,closed cycle magnetohydrodynamic power generation system research has been focused on improving the isentropic efficiency and the enthalpy extraction ratio.By reducing the cross-section area ratio of the disk magnetohydrodynamic generator,it is believed that a high isentropic efficiency can be achieved with the same enthalpy extraction.In this study,the result relating to a plasma state which takes into account the ionization instability of non-equilibrium seeded plasma is added to the theoretical prediction of the relationship between enthalpy extraction and isentropic efficiency.As a result,the electron temperature which reaches the seed complete ionization state without the growth of ionization instability can be realized at a relatively high seed fraction condition.However,the upper limit of the power generation performance is suggested to remain lower than the value expected in the low seed fraction condition.It is also suggested that a higher power generation performance may be obtained by implementing the electron temperature range which reaches the seed complete ionization state at a low seed fraction.