發(fā)布時間：2021-01-02 20:31

　　隨著X射線在醫(yī)療領(lǐng)域應(yīng)用的不斷發(fā)展,X射線的防護(hù)成為輻射防護(hù)與環(huán)境保護(hù)的關(guān)鍵技術(shù)問題。傳統(tǒng)X射線防護(hù)方案關(guān)注X射線的透射率,即降低X射線對外部環(huán)境和人員的損傷,而在醫(yī)療檢測過程中X射線的反射率直接影響了病人的輻射損傷。本文設(shè)計了一種新的X射線防護(hù)方案,該方案同時兼顧降低X射線防護(hù)板的透射率和反射率,其是由不同金屬材料按一定比例混合而成,其主要材料有:BaSO4、Fe3O4、NMnO2、Cu、Smo、Gdo、Bio、Wo和不飽和聚酯樹脂,并采用基于蒙特卡羅模擬方法的MCNP軟件對該X射線防護(hù)方案性能進(jìn)行了計算,在模擬中所選取的X射線能量在60keV到200keV之間,防護(hù)板的厚度取在1mm到9mm之間,同時計算X射線的反射率和透射率。由于不同金屬原子對不同波長和能量的光子的吸收能力不同,本文所采用的X射線防護(hù)板是由不同原子所組成的,其比單金屬原子制作的防護(hù)板（比如鉛板）具有更高的吸收率,能有效降低透射率和折射率。本文的模擬主要是分為以下兩個部分:首先,對給定能量的X射線,計算了不同厚度防護(hù)板的反射率和透射率。其次,對于最佳厚度的防護(hù)板,計算了防護(hù)板的反射率和透射率。最后,由不同板厚、成本... 

【文章來源】：華北電力大學(xué)(北京)北京市 211工程院校 教育部直屬院校

【文章頁數(shù)】：56 頁

【學(xué)位級別】：碩士

【文章目錄】：
摘要
Abstract
Acronyms And Abbreviations
Chaterl Introduction
    1.1 Introduction
    1.2 Problem Statement
    1.3 Objective Of Thesis
    1.4 Thesis Outlines
Chapter 2 Background Of X-Ray
    2.1 Introduction To X-Ray
    2.2 Advantages And Risks Of X-Rays
        2.2.1 Advantages of X-Ray
        2.2.2 Risks Of X-Ray
    2.3 Characteristics of X-Ray Emission
    2.4 Elements Of X-Rays
    2.5 X-Rays Production
    2.6 Some Applications Of X-Rays
    2.7 Electron Energy
        2.7.1 Potential
        2.7.2 Kinetic
Chapter 3 Principle Of X-Ray Interaction,Protection And Absorption
    3.1 Principle Of X-Ray Interaction
        3.1.1 Coherent Scattering
        3.1.2 Compton Effect
        3.1.3 Photoelectric Effect
        3.1.4 X-Ray Photon Interactions Pair Production
        3.1.5 X-Ray Photon Interactions Photodisintegration
    3.2 Absorption Of X-Rays
    3.3 Radiation Protection Of X-Ray
    3.4 Criteria For The Selection Of A Shield Material
        3.4.1 Attenuation Neutrons
        3.4.2 Thermal Heat Removal
        3.4.3 Attenuation Of Neutron Particles
    3.5 X-Ray Rooms:Design,Materials And Protection Barriers
        3.5.1 Warning Signs
        3.5.2 Occupancy Of X-Ray Rooms:Calculation Of Safety Aspects
        3.5.3 Room Size
        3.5.4 Walls: Materials And Lead Equivalence
        3.5.5 Windows
    3.6 Shielding Calculations
        3.6.1 Exponential Attenuation Of X Rays
        3.6.2 Design Goal（P）
        3.6.3 Uncontrolled P=0.1 Mgy/Y Will Satisfy 0.25 Msv/Y
        3.6.4 Occupancy Factor,T
        3.6.5 X-Ray Beam Transmission
        3.6.6 Archer Equation For Transmission Curves
        3.6.7 Workload（W）
        3.6.8 Update On Workload Data
        3.6.9 Models For Diagnostic X-Ray Shielding Calculations
        3.6.10 Calculation Of Primary Kerma
        3.6.11 Scatter Radiation
        3.6.12 Leakage Radiation
Chapter 4 X-Ray Protection Plate Design And Simulation
    4.1 Methodology
    4.2 System Model
Chapter 5 Conclusion And Future Work
    5.1 Conclusion
    5.2 Future Work
References
Acknowledgements
Publications during master



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