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1.
The BMPPT(4-benzoyl-2,4-dihydro-5-methyl-2-phenyl-3H-pyrazol-3-thione)was synthesized from BMPP.Its m.p.is 106-108℃,The results of the element analysis are as follows:C,68.51%,H,4.51%,N,9.26%,S.11.47%,which are in conformity with the theoretical value(C,69.15%,H,4.76%,N.9.52%,S.10.90%),The solvent extraction of Th^4 from nitric acid solution by BMPPT in benzene was studied.The extraction ability of BMPPT is not so high as that of its parent (BMPP).The Th^4 distribution ratio(DTh)in creases with the increasing pH of the aqueous phase,and pH1/2 for Th^4 was 3.2([BMPPT]=0.10mol/L),When the pH increases,the distribution ratio of Th^4 increasdes linearly with the slope of 1.59,When the concentration of BMPPT increases,the distribution ratio of Th^4 increases rapidly.The lgDTh-lg[BMPPT]is linear with the slope of 1.42 and the extraction mechanism is the cation ion-exchange.  相似文献   

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The ring-and side-chain-~(14)C-labeled probimane, 1,2-bis (4-morpholinomethy1-3,5-dioxopiperazin-1-yl) propane were synthesized from acetic acid-1-~(14)C in 4 steps and from ~(14)C-formaldehyde in 1 step respectively. The radiochemical yeild for the ring labeling was 28.1%; for the side-chain labeling was 18.5%.  相似文献   

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田原  田淑浩 《同位素》1996,9(3):136-139
以NaB^3H4还原1-(2-氧-3-甲氧丙基)-2-硝基-1H-咪唑制得1-「2-^3H」(2-羟基-3-甲氧丙基)-2-硝基-1H-咪唑。产品经硅胶-H柱洗脱,蒸馏,Sep-Pak C18柱处理,并经HPLC及液闪检测,化学纯度〉99.9%,放射化学纯度〉97%,比活度为16.05TBq/mol。  相似文献   

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刘胜吾 《国外核动力》2005,26(4):7-12,59
1 引言 2050年,地球上的人口将会达到80~100亿,与现在60亿人口的数字相对照,他们当中几乎有20亿人没有电力供应!能源需求将会相当大地增加,因为人类总是会自然地追求生活条件的改善,而且渴望均等共享经济进步带来的更多好处。  相似文献   

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超声波法合成2—^18F—2—脱氧—β—D—葡萄糖的初步研究   总被引:7,自引:2,他引:5  
采用超声波法合成2-^18F-2-脱氧-β-D-葡萄糖(^18F-FDG),以提高其合成效率。实验结果表明:F取代前体2位上亲核反应进行的程度与相转移催化剂和温度有关。无相转移催化剂时,84℃超声反应10min,亲核反应进行了70%;而在10mg的K2.2.2存在下,室温(22℃)下超声反应10min,亲核反应进行了85%,在84℃下超声反应2min,亲核反应进行了95%。同经典方法相比,超声波合成法^18F-利用率提高了10%,反应管的放射性吸附下降了5%。超声法合成效率(EOS)为60%,校正校率(EOB)为78%,合成时间为40min。仅用一根C-18纯化柱纯化,超声法合成的^18F-FDG中^18F^-含量低于1%。因此,采用超声波法合成^18F-FDG可明显提高合成效率。  相似文献   

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Food irradiation is gaining popularity worldwide and this technology is important to improve quality and reduce the post harvest losses of food. Because of the rapid commercialization of irradiated foods throughout the world, compliance of different regulations relating to use of technology in different countries and demand of consumers for clear labelling of irradiated foods, there is need for the development of analytical methods to detect radiation treatment of food. Among several methods studied so far, thermoluminescence (TL) is an important method that can be used to find out the irradiation history of food that contain even a very minute amount of dust particles. In this study, the irradiated and unirradiated wheat and rice samples were analyzed using the TL method. The samples were purchased from the local market of Peshawar and irradiated to radiation doses of 0.5 and 1.0 kGy using Co-60 gamma irradiator at the Nuclear Institute for Food and Agriculture (NIFA), Peshawar. The mineral contaminants were isolated by jet water, ultrasonic treatment, and density gradient. TL glow curves of the isolated minerals from irradiated and unirradiated samples were recorded between the temperature ranges of 50-500℃ using a TL reader. Generally, the glow curves for irradiated samples showed much higher TL intensities (TL1) than the unirradiated samples. The results were normalized by rerradiation of mineral samples to gamma-ray dose of 1.0 kGy followed by determination of the second glow curves (TL2). The ratio of the area of first glow curve to that of second glow curve (TL1/TL2) was calculated for selected temperature intervals and compared with the recommended values for unirradiated and irradiated samples. Finally, the shapes of the glow curves for irradiated and unirradiated samples were also analyzed. On the basis of these results (comparison of TL-intensities, TL1/TL2 ratios and shapes of the glow curves), all the irradiated and unirradiated samples of wheat and rice were unequivocally identified.  相似文献   

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The paper is to study pharmacologic characteristics of 18F-FP-β-CIT (18F-N-(3-fluoropropyl)-2β- carbomethoxy-3β- (4-iodophenyl)nortropane) as an imaging agent for dopamine transporter. The radiochemical purity of 18F-FP-β-CIT in aqueous solution was over 95% after standing at room temperature for 4h. Biodistribution displayed rapid uptake in rat brain (1.375 %ID/organ at 5min and 0.100 %ID/organ at 180 min) and the striatal uptake was 1.444,0.731, 0.397, 0.230 and 0.146 %ID/g at 5, 30, 60, 120 and 180 min, respectively. The values of striatum/cerebellum,striatum/frontal cortex and striatum / hippocampus in rat's brain at 30 min were 3.38, 2.17 and 2.40 respectively. The uptake in striatum can be blocked by β-CFT, suggesting that 18F-FP-β-CIT binds to DAT peculiarly. The compound was rapidly cleared from monkey's blood. The striatal uptake was bilaterally decreased in the left-sided lesioned PD rats, compared with normal control. Brain PET imaging studies in normal monkey showed that 18F-FP-β-CIT was concentrated in striatum. The test of undue toxicity showed that the dose received by mice was 1250 times as by human, which indicates that 18F-FP-β-CIT is very safe. So 18F-FP-β-CIT is a promising PET imaging agent for DAT with safety and validity.  相似文献   

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Pulsed photo-stimulated luminescence (PPSL) is a simple screening method that can be employed qualitatively at the spot for the detection of eggs treated with ionizing radiation.Due to the variations in the results during storage,the eggs of ostrich,duck,hen,and quail were irradiated to doses of 0,1,2,and 3 kGy.Most of the samples were incorrectly identified during storage after four months of irradiation.Thermoluminescence (TL) technique was also tried by using egg shells in order to confirm the irradiation treatment in eggs.TL glow curves were recorded between the temperatures 50℃to 400℃at the rate of 5°/s for all the control and irradiated samples.On the basis of integrated areas of first glow curves (TL1),the glow curve ratios (TL1/TL2) and the shapes of maxima of TL1, the irradiation treatment of all the eggs was confirmed.Furthermore,the presence of calcite and aragonite minerals that cause the TL signal in the egg shells were studied using X-ray diffraction spectrometry.  相似文献   

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Soil samples in and around salt field area have been analyzed for natural radioactivity concentration using gamma ray spectrometer.The activity concentration for ~(232)Th,~(238)U and ~(40)K are ranged from 27.88 to 45.27 Bq/kg, from BDL to 13.30 Bq/kg,and from 135.54 to 381.28 Bq/kg,respectively.The measured activity concentrations for these radionuclides were compared with world average activity of soil.The average activity concentration of ~(232)Th in the present study is 1.19 times higher than world median value while the activity of ~(238)U and ~(40)K is found to be lower. The absorbed dose rates due to these radionuclides were calculated.The average absorbed gamma dose rate due to the presence of ~(232)Th,~(238)U and ~(40)K in soil samples is 36.99 nGy·h~(-1).These results indicate no radiological anomaly. The data presented in this study will serve as a base line survey for primordial radionuclides concentration in the study area.  相似文献   

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Due to relatively high uptake of glucose in the brain cortex, the use of FDG PET imaging is greatly limited in brain tumor imaging, especially for low-grade gliomas and some metastatic tumours. More and more tracers with higher specificity were developed lately for brain tumor imaging. There are 3 main types of non-FDG PET tracers: amino acid tracers, choline tracers and nucleic acid tracers. These tracers are now widely applied in many aspects of brain tumor imaging. This article summarized the general use of non-FDG PET in different aspects of brain tumor imaging.  相似文献   

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在军控核查中,核部件的质量、丰度、年龄属性需采用无损方法进行核查,NPL-NMC系统是一套利用中子多重性测量核部件质量属性的装置,为建立完善的属性测量系统,还需在NPL-NMC系统的基础上建立γ测量子系统。本文通过设计γ测量子系统在NPL-NMC系统上的布局及对中子屏蔽的优化,使系统能对铀部件的丰度、年龄属性进行测量。模拟计算结果表明,该γ测量子系统能很好地满足军控核查对铀部件丰度、年龄属性测量的要求。  相似文献   

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为有效实现数字射线扫描成像检测系统性能的定量分析评价,据此进行检测工艺参数的优化,对数字射线扫描成像检测系统调制传递函数(Modulation transfer function,MTF)进行了测试分析。采用刀口工具、双线型像质计、分辨率测试卡,对系统在不同焦点大小、放大倍数、运动方向的检测情况,分别进行了MTF的测试并进行了比较。结果表明,双线型像质计与分辨率测试卡的测试结果基本一致,但双线型像质计更便于对比度的定量计算;双线型像质计的对比度传递函数近似符合二次曲线,经转换得到的调制传递函数值高于刀口法的测试值,刀口法计算数值偏低的原因在于运动不平稳所带来的不利影响。分析表明,数字射线扫描成像系统性能受到多个因素的共同影响,MTF测试结果可较全面地对影响因素进行定量评价,可用于确定最佳的检测参数或找出等价的参数组合。  相似文献   

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Carbon fiber-reinforced advance composites have been used for structural applications,mainly on account of their mechanical properties.The main factor for a good mechanical performance of carbon fiber-reinforced com- posite is the interfacial interaction between its components,which are carbon fiber and polymeric matrix.The aim of this study is to improve the surface properties of the carbon fiber using ionizing radiation from an electron beam to obtain better adhesion properties in the resultant composite.EB radiation was applied on the carbon fiber itself before preparing test specimens for the mechanical tests.Experimental results showed that EB irradiation improved the ten- sile strength of carbon fiber samples.The maximum value in tensile strength was reached using doses of about 250 kGy.After breakage,the morphology aspect of the tensile specimens prepared with irradiated and non-irradiated car- bon fibers were evaluated.SEM micrographs showed modifications on the carbon fiber surface.  相似文献   

20.
基于物理体模CT图像的1岁儿童体素体模构建   总被引:1,自引:1,他引:0  
本文介绍了基于1岁儿童物理体模(Model 704-D)的CT图像和中国成年男性参考人体素体模(CRAM)的1岁儿童体素体模(CPP01)的构建,包括通过对物理体模扫描得到OCP01体模(基于儿童物理体模的CT图像建立的一粗略的体素体模),进而构建和优化CPP01。该体素体模的各器官组织的质量与GBZ/T 200.2-2007所给数据的相对偏差约在5%以内,且其外部轮廓和主要器官的位置与Model 704-D相匹配。  相似文献   

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