~(60)Coγ辐射装置增源后剂量场最佳分布及剂量测定

在 60 Coγ辐射装置增源启用前 ,对源棒进行了合理排布 ,而获得辐射场最佳剂量分布。用砝码剂量仪和硫酸亚铁剂量计 ,准确测量了源到辐照位置的重复性和辐射场空间剂量率。剂量测试结果与国家计量院比对具有较好的一致性。     

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%.     

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。     

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.     

~(60)Co-γ辐照装置高剂量场的标定

根据重新制作的重铬酸钾(银)剂量计,对γ射线辐射场进行测量。结果表明,剂量计测量重复性较好,相对偏差为2.35%。辐射场的角向和径向剂量呈均匀性分布,而垂直方向在一定高度范围内呈均匀性分布。     

医用诊断螺旋计算机断层摄影装置（CT）X射线辐射源测量不确定度评定

以医用诊断螺旋计算机断层摄影装置（CT）X射线辐射源为例,分析了用剂量计测量医用诊断螺旋计算机断层摄影装置（CT）X射线辐射源的误差来源,并对各不确定度分量进行了评估,并在此基层上给出了扩展测量不确定度。     

聚苯乙烯量热计的研制及其应用

为测量３￣５ＭｅＶ电子束的吸收剂量，研制了一台聚苯乙烯量热计，并实现了计算机控制的在线测量，不仅可以简单，快速，可靠地测量电子束吸收剂量，而且可以作为标准剂量计刻度传递剂量计和工作剂量计。     

光纤γ辐照感生损耗的研究

对几种国产光纤进行了γ辐照感生损耗谱的测量．发现光纤经辐照后，在０．６～０．７μｍ波段产生强烈吸收峰，在０．８～１．２μｍ区域感生损耗变化平缓，大于１．２μｍ有上升的趋势；同时给出了多模梯度光纤在０．８５μｍ波长下辐照感生损耗随辐照剂量变化的经验公式．γ辐照引起的顺磁缺陷中心导致光纤γ辐照感生损耗的产生．     

γ射线对Ge-As-Se硫系玻璃的辐照效应

对Ge-As-Se玻璃系统,进行了高能γ射线辐照试验。结果表明:辐照使样品的密度(ρ),热膨胀系数(α)和光学带隙(Eopt)等参数产生了变化,并与组成有关。样品的组成为化学计量比时,其辐照灵敏度与As2Se3含量具有线性规律,而非化学计量比组成的样品无明显规律性关系。这是γ射线引起玻璃化学键和结构变化而产生的效应。硒化物硫系玻璃在作为剂量计材料应用方面具有良好的前景。     

组分含量对PVG膜剂量计偏差的影响

对辐射致色薄膜剂量计（ＰＶＧ膜剂量计）的辐照响应过程进行了研究,计算出了ＰＶＧ膜剂量计中孔雀绿（ＭＧ＾＋）的辐射化学产额Ｇ（ＭＧ＾＋）当膜中组分隐色孔雀绿（ＬＭＧ）的量含量为８０μｍｏｌ·ｇ＾－１,有机卤代物（ＲＸ）与ＬＭＧ的质量比为０．５时,其Ｇ值为０．２３６μｍｏｌ·Ｊ＾－１,考查了膜中组分ＬＭＧ和ＲＸ的量含量变化对Ｇ（ＭＧ）的影响,表明ＰＶＧ膜剂量计中由于ＬＭＧ和ＲＸ的量含量波动而引起的偏差     

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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