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碘标白藜芦醇及其小鼠体内分布 总被引:1,自引:0,他引:1
通过碘131标记白藜芦醇探讨白藜芦醇在小鼠体内的分布代谢。采用过氧化物酶法对白藜芦醇进行131I标记;经乙酸乙酯萃取纯化,以聚酰胺薄膜为支持介质,V(三氯甲烷)∶V(丙酮)∶V(乙醇)∶V(水)=4∶4∶0.5∶0.4为展开剂,测定标记物的标记率和放化纯;KM小鼠尾静脉注射131I白藜芦醇(每只0.185MBq,n=5)。131I白藜芦醇标记率达69.3%,萃取分离后其放化纯为959%,3、7和15d后分别为92.0%、90.4%、90.1%;动物实验显示,131I白藜芦醇在小鼠体内广泛分布,主要经肝和肾进行代谢,5min时每克组织百分注射剂量率(%ID•g-1)分别为16.35、13.05,在肠中也有较高分布,10min时%ID•g-1为11.70;甲状腺的摄取率随时间的延长而增加。碘标白藜芦醇标记物较稳定,可用于进一步的微量示踪研究。 相似文献
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扩散过程是主导氡在铀矿岩中运移与析出的主要方式。铀矿原岩辐射较大且取样困难,不利于开展有关室内实验。为了解决以上问题,依据相似理论,以某花岗岩为原型,选取石英砂、铀尾砂、水泥、精铁粉和微硅粉等为原材料,制备了3种不同材料配比的圆柱形类铀矿岩试样,并测定了原型和试样的物理力学参数;然后采用密闭腔体法测量了原型和试样在不同包裹方式下的累积氡浓度,推导氡的扩散性能参数的计算公式,通过计算获得了原型和试样的氡扩散长度和扩散系数。实验结果表明:花岗岩原型与所制备的类铀矿岩的颗粒密度、抗压强度、抗拉强度、内聚力和内摩擦角相似比的均值分别为1.09∶1、3.93∶1、4.28∶1、3.47∶1和1.00∶1;花岗岩原型的扩散系数为0.146×10-6m2·s-1,类铀矿岩的扩散系数介于0.114×10-6~0.594×10-6m2·s-1之间,两者的相似比介于0.25∶1~1.28∶1之间。研究认为所制备的试样3在一定程度上可用来模拟花岗岩型铀矿岩,以满足室内实验的需求。 相似文献
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采用88Sr模拟放射性核素90Sr,Ce4+模拟四价锕系放射性核素。以分析纯SrCO3、CeO2和TiO2为主要原料,通过高温固相反应制备SrCeTi2O7人造岩石固化体。对固化体的烧成工艺、物理性能、晶体结构及微观形貌进行研究,并对固化体的热稳定性及抗浸出性能进行探讨。结果表明,选择配方n(SrCO3)∶n(CeO2)∶n(TiO2)=1∶1∶2,在1 450 ℃ 下保温5 h可合成结构致密、晶型发育完整的SrCeTi2O7人造岩石固化体;Dicvol程序指标化结果表明,该固化体化合物属四方晶系,晶胞参数为a=0.387 33(4) nm,c=0.388 07(5) nm;SrCeTi2O7人造岩石固化体具有良好的热稳定性,经高达800 ℃ 热处理后样品仍保持原有物相不变;PCT-B粉末浸泡法测试结果表明,SrCeTi2O7人造岩石固化体具有较好的抗浸出性能,浸泡周期28 d时Sr、Ce和Ti的浸出率分别为3.51×10-4、8.23×10-8和2.02×10-7 g /(m2·d)。 相似文献
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本文采用涂布法制备了一系列H310BO3/ZnS(Ag)闪烁体转换屏样品,对其成分配比进行了优化。结果表明,最佳的H310BO3/ZnS(Ag)质量比在1∶6~1∶7之间,最佳的黏合剂用量为总质量的25%。利用中子照相设备对转换屏的发光均匀性进行了成像分析,结果显示光输出非常均匀;对楔形镉条进行中子成像,并采用调制传递函数(modulation transfer function,MTF)方法计算了系统分辨率,结果显示,在MTF值为0.1时,对于厚度分别为270(11)、350(14)、404(9)及505(15)μm的转换屏,其相应的系统空间分辨率分别为255.6、315.9、371.0和471.3 μm。 相似文献
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合成了N,N′-二乙基-N,N′-二苯基-[2,2′-联吡啶]-6,6′-二硫代酰胺(Et-Ph-BCTABipy)萃取剂,并利用13C NMR和1H NMR对其进行了表征;研究了相接触时间、萃取剂浓度、水相初始酸度和Pd2+浓度等因素对Et-Ph-BCTABipy萃取Pd2+性能的影响,利用摩尔比法确定了Et-Ph-BCTABipy与Pd2+所形成的配合物组成;同时,在Ln(Ⅲ)与Pd2+共存体系中研究了Et-Ph-BCTABipy对Pd2+的萃取选择性。结果表明:Et-Ph-BCTABipy在HNO3体系中对Pd2+具有较强的萃取性能和较高的萃取选择性;萃取过程中Et-Ph-BCTABipy与Pd2+以1∶2的比例结合,其萃取平衡常数Kex=3.42×106。 相似文献
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本文以沸石、硅灰、石英砂为添加剂,按照质量比m(沸石)∶m(硅灰)∶m(石英砂)∶m(水泥)=1∶1∶3∶10配方对模拟放射性含氟废液进行水泥固化。由配方得到的水泥浆流动度和初、终凝时间满足桶内固化要求。测定了水泥固化体28 d的抗压强度、抗浸泡性和抗冻融性实验后的强度损失,进行了抗冲击性能测试和模拟核素浸出实验。结果表明,该配方可有效地固化模拟放射性含氟废液,固化体28 d抗压强度、各项实验强度损失和模拟核素浸出率均满足GB 14569.1-2011的要求。水泥固化体的F-浸出率很低,XRD显示F-以CaF2形式存在。废液中F-质量分数控制在1%较为合适,此时水泥固化体终凝时间为14 h,F-的42 d浸出率为2.54×10-3 cm/d。 相似文献
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合成了N,N′-二乙基-N,N′-二苯基-[2,2′-联吡啶]-6,6′-二硫代酰胺(Et-Ph-BCTABipy)萃取剂,并利用13C NMR和1H NMR对其进行了表征;研究了相接触时间、萃取剂浓度、水相初始酸度和Pd2+浓度等因素对Et-Ph-BCTABipy萃取Pd2+性能的影响,利用摩尔比法确定了Et-Ph-BCTABipy与Pd2+所形成的配合物组成;同时,在Ln(Ⅲ)与Pd2+共存体系中研究了Et-Ph-BCTABipy对Pd2+的萃取选择性。结果表明:Et-Ph-BCTABipy在HNO3体系中对Pd2+具有较强的萃取性能和较高的萃取选择性;萃取过程中Et-Ph-BCTABipy与Pd2+以1∶2的比例结合,其萃取平衡常数Kex=3.42×106。 相似文献
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B.S.Rajanikanth A.D.Srinivasan B.AryaNandiny 《等离子体科学和技术》2003,5(3):1825-1833
A cascaded system of electrical discharges(non-thermal plasma)and adsorption process was investigated for the removal of oxides of Nitrogen(NOx) and total hydrocarbons (THC) from an actual diesel engine exhaust.The non-thermal plasma and adsorption processes were separately studied first and then the casecaded procxess was studied.In this study,different types of adsorbents were used.The NOx removal efficiency processes and the removal efficiency was found almost invariant in time.When associated by plasma,among the adsorbents studied.Activated charcoal and MS-13X were more effective for NOx and THC removal respectively.The experiments were conducted at no load and at 50% load conditions.The plasma reactor was kept at room temperature throughout the experiment,while the temperature of the adsorbent reactor was varied.A relative comparison of adsorbents was discussed at the end. 相似文献
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23-羟基白桦酸的碘标记及其在荷肝癌HepA肿瘤鼠体内的分布 总被引:1,自引:0,他引:1
采用双氧水法对23-羟基白桦酸进行131I标记;以硅胶纸为支持介质,V=氧甲烷∶V甲醇=9∶1为展开剂,测定标记率及标记物放化纯;ICR小鼠和荷肝癌HepA肿瘤鼠尾静脉注射131I-23-羟基白桦酸(0.74 MBq/只)后考察标记物的药代动力学性质及荷瘤鼠体内分布.结果显示,131I-23-羟基白桦酸标记率达98%,其放化纯在1、4、8 d分别为98.5%、97.3%、95.8%.131I-23-羟基白桦酸在正常小鼠体内血液清除较快,其药代动力学模型符合二室模型.注射后0.5 h荷肝癌HepA肿瘤鼠肝摄取最高(9.14%ID·g-1组织),其次为肾、血、脾、肠、肺、肿瘤,脑中分布最少,仅为0.28%ID·g-1组织;肿瘤/肌肉比值>3.表明碘标23-羟基白桦酸标记率高,标记物稳定;碘标记物在荷肝癌HepA肿瘤鼠中的肿瘤靶向摄取提高2倍,可能是一新型增效的核素靶向治疗药物. 相似文献
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PE-AA辐射接枝共聚合的反应历程研究 总被引:1,自引:0,他引:1
研究了聚乙烯(PE)与丙烯酸(AA)、甲基丙烯酸(MAA)的接枝共聚反应,探讨了接枝反应过程及特征:单体首先在PE表面接枝,然后进入内部进行本体接枝。研究表明:表面接枝为动力学控制,本体接技系扩散控制,单体在膜内的扩散与单体极性及聚合物的结晶度等有关 相似文献
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为了探索前期自行合成的一种碘(131I)代二肽胺作为放射性药物的可能性,本文对其体外稳定性、亲脂性、急性毒性进行了考察。首先采用封管法对二肽胺进行了碘的标记,获得了标记率为85%左右的配合物;通过将配合物放置不同时间测量络合率的变化得到配合物的稳定性结果;采用摇瓶法来考察配合物的亲脂性;对配合物对实验动物的肝脏功能、外周血象的影响作了考察。结果说明,配合物是亲脂性的,毒性较低,3d后的脱碘率为13%左右。成功建立了VX2肝癌单发肿瘤兔模型,得到了配合物在正常小鼠和肿瘤大白兔体内的分布结果,配合物在动物模型以及在正常小鼠的体内分布趋势比较一致,配合物比较倾向于浓集于脂肪组织,在肿瘤组织中的滞留量相对较高,表现出作为肿瘤治疗药物的潜在可能性,但清除较快,可以作进一步的研究,提高标记物的体内稳定性,以延长配合物在靶向组织中的浓集时间。 相似文献
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Copper thin films were deposited by plasma-enhanced atomic layer deposition at low temperature, using copper(I)-N,N′-di-sec-butylacetamidinate as a precursor and hydrogen as a reductive gas. The influence of temperature, plasma power, mode of plasma, and pulse time, on the deposition rate of copper thin film, the purity of the film and the step coverage were studied.The feasibility of copper film deposition on the inner wall of a carbon fibre reinforced plastic waveguide with high aspect ratio was also studied. The morphology and composition of the thin film were studied by atomic force microscopy and x-ray photoelectron spectroscopy,respectively. The square resistance of the thin film was also tested by a four-probe technique. On the basis of on-line diagnosis, a growth mechanism of copper thin film was put forward, and it was considered that surface functional group played an important role in the process of nucleation and in determining the properties of thin films. A high density of plasma and high free-radical content were helpful for the deposition of copper thin films. 相似文献
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J. Kotakoski A.V. Krasheninnikov K. Nordlund 《Nuclear instruments & methods in physics research. Section B, Beam interactions with materials and atoms》2005,240(4):810-818
We have studied the low energy irradiation of carbon nanotubes (CNT) with K ions using classical molecular dynamics simulations with analytical potentials. The studied CNTs had diameters of about 0.5–1.2 nm and single or multiple walls. The average penetration depth and probabilities to introduce an impurity atom into CNT were studied with simulations on irradiating the CNT with single K ion. The number of potassium clusters, their average sizes and the damage produced into the CNT due to the irradiation were studied using multiple K ion irradiations. We found that the K ions are mobile in CNTs right after the implantation event and that they cluster together. For CNTs with 1–3 coaxial tubes, the highest ratio of K atoms in clusters per total number of K ions was obtained by using an irradiation energy of about 100 eV. Also the least damage per K ion was found to be produced into the CNT with this energy when those energies high enough for the ion to penetrate the outermost wall of the CNT were considered. 相似文献