丙氨酸应用于辐射治疗水平的剂量学性能研究

研究自制的丙氨酸剂量计应用于辐射治疗水平吸收剂量测量的剂量测量重复性、剂量率依赖性、剂量响应线性。利用电子直线加速器产生的6MVΧ射线辐照丙氨酸剂量计,测得其剂量测量的重复性为2.6%(1σ);剂量率范围为1~6G y/m in时,剂量响应变化为1.9%(1σ);利用钴治疗机发射的γ射线,照射剂量范围为(1~10G y),测得ESR响应值随吸收剂量变化的线性相关系数为0.9996。丙氨酸剂量计的合成标准不确定度为3.3%,能满足辐射治疗水平剂量测量的要求,但剂量测量的重复性有待改进。     

CdZnTe个人剂量计能响特性的Monte Carlo模拟

为了获得合适的CdZnTe(CZT)个人剂量计的剂量-能量响应补偿方案,利用Monte Carlo程序MCNP4C对CZT、CZT加各种补偿物质和CZT在不同电子学下阀的剂量-能量响应特性进行了模拟计算。通过模拟得到了2种CZT个人剂量计剂量补偿方案:在CZT(5mm×5mm×5mm)前加15mm Pb(带有阶梯孔)和2mm Pb(带有孔面积为Pb截面面积3%的孔,并分高、低能两能量道计数)。为今后的CZT个人剂量计设计提供了理论依据。     

~(60)Co-γ射线辐照绿豆对其贮藏期及品质影响的研究初报

利用0.1KGy剂量的~(60)Co—γ射线辐照绿豆,可以完全杀灭绿豆象,进行绿豆长期贮藏,在此剂量下绿豆营养成份,发芽率等未见明显变化。     

OWG辐射变色剂量计测量方法的研究——751G型单光束分光光度计的应用

1 引言1981年美国Kronenberg和McLaughlin等首先使用辐射变色三苯甲基氰化物无色染料溶液和含氟塑料细管研制出0WG(0ptical Wave-Guide)辐射剂量计,1983年美国远西技术公司就批量生产5cm长的FWT—70 OWG辐射剂量计及与之配套的FWT-98专用读数计,使之迅速达到了实用化阶段。该剂量计的研制之所以能发展如此迅速,是由于其具有尺寸小、结构坚固、辐照前后存放稳定性好,操作使用方便,剂量复盖范围适中(10—10~4Gy),很适合于某些辐射加工领域尤其是食品辐射加工中的吸收剂量监测及质量控制。     

丙氨酸—ESR剂量计剂量学基本特性的研究

研究了丙氨酸-ESR 剂量计剂量学基本特性,以及剂量计元件的制备工艺.在0.1～10kGy 的剂量范围内有良好的线性响应,ESR 信号主峰幅值与相应剂量之间线性相关系数大于0.9999.为了提高测量精度,设计一种装置,使样品管位置下端固定,剂量计元件信号幅值的单次测量相对偏差从±1.1%改善到±0.45%.修正了 ESR 波谱仪增益系数之间的线性关系.对1kGy一组剂量计元件信号幅值分散性进行了检验,其相对标准偏差为±0.55%.剂量计元件辐照温度响应值的校正系数为0.20%±0.02%℃~(-1).吸收剂量在1.1kGy 点的总不确定度小于4.5%.     

PVG膜剂量计线性响应范围的估计

对辐射致色薄膜剂量计（ＰＶＧ）的辐照响应过程进行了研究，发现其剂量响应曲线上有一极大点，考查了隐色孔雀绿（ＬＭＧ）的极大转化率Ｃｅｘｔ与隐色孔雀绿（ＬＭＧ）和有机齿代物（ＲＸ）量含量的关系，进而讨论了ＰＶＧ膜剂量计线性响应范围的上限与膜中ＬＭＧ是含量的关系。在该体系中当ＬＭＧ量含量在２０～１００μｍｏｌ·ｇ＾－１范围内时，其线性响应范围时上限估计在１４０～１１０ｋＧｙ范围内。     

^60Coγ射线辐照明胶的研究

~(60)Coγ射线辐照明胶是解决其细菌污染和粘度下降问题的有效方法。试验结果表明,适宜辐照剂量范围为3—5KGy,生产应用一般可控制在3.5KGy。在适宜剂量范围内,对其营养成分无不良影响,18种氨基酸总量比未辐照的对照微增。九十天动物喂养试验证明,对生长发育无不良影响,并有促进作用。血液化验、内脏器官观察和病理检验结果,均无异常改变。微核、染色体致畸、Ames试验均呈阴性。生产应用证明,经辐射可有效地提高产品质量和档次,社会、经济效益十分显著。     

薄膜剂量计聚乙烯—丙烯酸接枝膜的制备及染色

用丙烯酸接枝后的聚乙烯薄膜,可用一些水溶性的染料进行染色,制成有色聚乙烯薄膜剂量计.采用~(60)Co-γ射线引发基膜与单体共辐照的方法进行接枝,研究了剂量率对接枝率的影响.本法操作简便并可降低接枝剂量.同时还研究了染料浓度,染色温度及接枝率对染色的影响,确定了最佳染色条件.     

蜂胶黄酮Pinobanksin-3-acetate对结肠癌HCT-116细胞增殖及凋亡的影响

 为探讨蜂胶黄酮(Pinobanksin-3-acetate, PB3A)对结肠癌HCT-116 细胞增殖及细胞凋亡的影响, 采用四甲基偶氮唑盐(MTT)比色法, 检测不同浓度、不同时间PB3A、5-氟尿嘧啶(5-FU)及两种药物联合作用对HCT-116 细胞生长所产生的影响, 倒置显微镜观察细胞的形态学变化特点, Annexin V-FITC/PI 双染色、流式细胞仪检测药物作用24 h 后的细胞凋亡率。结果显示, PB3A 对HCT-116 细胞增殖有明显的抑制作用, 并呈浓度和时间依赖性。其抑制活性与5-FU 几乎没有显著性差异, 联合用药具有协同效应; 在一定剂量范围内, 可见凋亡细胞明显增多。流式细胞仪分析结果表明, 细胞凋亡率明显上升, 呈剂量依赖性。PB3A 对HCT-116 细胞具有明显的增殖抑制和诱导细胞凋亡作用。     

光纤布拉格光栅湿度传感器研究

基于光纤布拉格光栅(FBG)的应力传感特性,提出了一种湿度传感方法,给出了湿度传感器的设计和实验测量系统。理论推导显示,涂有湿敏材料的FBG对湿度的传感可转化为对应变的快速响应,结合温度的有效补偿,可以共同反映在FBG中心反射波长的漂移上。研究结果表明,FBG湿度传感器能在较大温度范围内保持线性特性,并具有稳定性持久、响应速度快等优点。     

Markedness and its Interpretation in Language Use

Language markedness is a common phenomenon in languages, and is reflected from hearing, vision and sense, i.e. the variation in the three aspects such as phonology, morphology and semantics. This paper focuses on the interpretation of markedness in language use following the three perspectives, i.e. pragmatic interpretation, psychological interpretation and cognitive interpretation, with an aim to define the function of markedness.     

Features of Women's language

Language is a means of verbal communication. People use language to communicate with each other. In the society, no two speakers are exactly alike in the way of speaking. Some differences are due to age, gender, statue and personality. Above all, gender is one of the obvious reasons. The writer of this paper tries to describe the features of women＇s language from these perspectives： pronunciation, intonation, diction, subjects, grammar and discourse. From the discussion of the features of women＇s language, more attention should be paid to language use in social context. What＇s more, the linguistic phenomena in a speaking community can be understood more thoroughly.     

低渗透非均质砂岩油藏启动压力梯度研究

理论推导与室内实验相结合,建立了低渗透非均质砂岩油藏启动压力梯度确定方法。首先借助油藏流场与电场相似的原理,推导了非均质砂岩油藏启动压力梯度计算公式。其次基于稳定流实验方法,建立了非均质砂岩油藏启动压力梯度测试方法。结果表明:低渗透非均质砂岩油藏的启动压力梯度确定遵循两个等效原则。平面非均质油藏的启动压力梯度等于各级渗透率段的启动压力梯度关于长度的加权平均;纵向非均质油藏的启动压力梯度等于各渗透率层的启动压力梯度关于渗透率与渗流面积乘积的加权平均。研究成果可用于有效指导低渗透非均质砂岩油藏的合理井距确定,促进该类油藏的高效开发。     

On Tragic Consciousness In The Works By Ernest Hemingway

As an American modern novelist who were famous in the literary world, Hemingway was not a person who always followed the trend but a sharp observer. At the same time, he was a tragedy maestro, he paid great attention on existence, fate and end-result. The dramatis personae's tragedy of his works was an extreme limit by all means tragedy on the meaning of fearless challenge that failed. The beauty of tragedy was not produced on the destruction of life, but now this kind of value was in the impact activity. They performed for the reader about the tragedy on challenging for the limit and the death.     

Achieving Unusual States of Matter Under High Pressure

正The periodicity of the elements and the non-reactivity of the inner-shell electrons are two related principles of chemistry,rooted in the atomic shell structure.Within compounds,Group I elements,for example,invariably assume the+1 oxidation state,and their chemical properties differ completely from those of the p-block elements.These general rules govern our understanding of chemical structures and reactions.Using first principles calcula-     

Exchange-Correlation and Electronic Excitation Energies from Pairing Matrix Fluctuations

We have developed an adiabatic connection to formulate the ground-state exchange-correlation energy in terms of pairing matrix linear fluctuations.This formulation of the exchange-correlation energy opens a new channel for density functional approximations based on the many-body perturbation theory.We illustrate the potential of such approaches with an approximation based on the particle-particle Random Phase Approximation(pp-RPA).This re-     

Density Functional Theory for the Response of Periodic Systems to Electric Fields Based on the Vector Potential Approach

正The electronic and nuclear(structural/vibrational)response of 1D-3D nanoscale systems to electric fields gives rise to a host of optical,mechanical,spectral,etc.properties that are of high theoretical and applied interest.Due to the computational difficulty of treating such large systems it is convenient to model them as infinite and periodic(at least,in first approximation).The fundamental theoretical/computational problem in doing so is that     

On the Thermodynamic Limit for Responses to Static Electromagnetic Fields

For molecular systems,the quantum-mechanical treatment of their responses to static electromagnetic fields usually employs a scalar-potential treatment of the electric field and a vector-potential treatment of the magnetic field.Although the potential for each field separately is associated with the choice of an(unphysical)origin,the precise choice of the origin for the electrostatic field has little consequences for the results.This is different for the     

Call for Papers

<正>"The Journal of Shanghai Normal University:Mathematics"is published by Shanghai Normal University as regular issues of The Journal of Shanghai Normal University each year from 2014 in English.The editors-in-chief of the issues are professors Yuhao Cong and Maoan Han.The Journal of Shanghai Normal University was started in 1958 with     

Journal of Donghua University ( English Edition) Contents of Volume 31

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