In order to compare the dosimetric properties of two kinds of solid state detectors used for monitoring ex- ternal exposures,experiments were performed for the GD-300 series of radiophotoluminescent glass detectors (R...In order to compare the dosimetric properties of two kinds of solid state detectors used for monitoring ex- ternal exposures,experiments were performed for the GD-300 series of radiophotoluminescent glass detectors (RPLGD)and the GR-200 series of thermoluminescent detectors(TLD).X-rays and ^(137)Cs and ^(60)Coγ-rays were used to irradiate the RPLGDs and TLDs,their dose linearity,uniformity/reproducibility of signal,fading effect and energy dependence were compared.Both kinds of the detectors have generally good dosimetric properties.The dose linearity and energy dependence of the GD-351 dosimeters and the TLDs are nearly the same,but the RPLGD is much better than the TLD in terms of the uniformity and fading effect.展开更多
The Delta4 3D dose verification device was commissioned in the current work for pre-treatment quality assurance (QA) of Intensity Modulated Radiotherapy (IMRT) and Volumetric Modulated Arc Therapy (VMAT) plans. The cr...The Delta4 3D dose verification device was commissioned in the current work for pre-treatment quality assurance (QA) of Intensity Modulated Radiotherapy (IMRT) and Volumetric Modulated Arc Therapy (VMAT) plans. The cross calibration and relative array calibration were performed to enable absolute dose comparison. The linearity of response with dose and temperature sensitivity tests were also conducted to investigate dosimetric properties of the Delta4 device. The need to modify the original CT image of the Delta4 phantom for accurate dose calculation and comparison is addressed in this work, applying a CT extension algorithm. A number of test plans varying from simple 4—field conformal to IMRT and VMAT plans were measured to evaluate the accuracy of this device. It was found that the Delta4 device measured dose accurately to within ±1%. In order to maintain this level of accuracy the machine output fluctuations need to be corrected prior to each measurement and the relative array calibration needs to be performed every six months.展开更多
为了研究光释光（OSL）技术,设计了OSL剂量探测系统。采用Landauer单点剂量片作探测器,敏感材料为Al2O3：C,并在CW-OSL模式下对系统进行了本底评估、剂量线性和最小可探测剂量（MDD）测试。实验结果表明,该系统本底控制在150 cps的较低...为了研究光释光（OSL）技术,设计了OSL剂量探测系统。采用Landauer单点剂量片作探测器,敏感材料为Al2O3：C,并在CW-OSL模式下对系统进行了本底评估、剂量线性和最小可探测剂量（MDD）测试。实验结果表明,该系统本底控制在150 cps的较低水平,处于国内领先水平;探测器经60Co标准源辐照后,在1～100 m Gy剂量范围内具有良好的线性响应;MDD为1μGy。展开更多
针对国内数字电子个人剂量计种类繁多、测量原理不同导致其性能差异显著进而不利于个人剂量的有效监督的情况。按照国家标准和规程要求,设计新一代个人剂量计Nt2000,并在标准辐射场中对该仪器进行了相对固有误差、剂量线性、重复性、能...针对国内数字电子个人剂量计种类繁多、测量原理不同导致其性能差异显著进而不利于个人剂量的有效监督的情况。按照国家标准和规程要求,设计新一代个人剂量计Nt2000,并在标准辐射场中对该仪器进行了相对固有误差、剂量线性、重复性、能量响应和角响应测试。测试结果表明：Nt2000个人剂量计主要性能指标满足国标要求,能量响应（48--1 250 ke V）优于±28%,可部分替代国外同类仪器。展开更多
基金Supported by the National Natural Science Foundation of China(Grant No.10675036)
文摘In order to compare the dosimetric properties of two kinds of solid state detectors used for monitoring ex- ternal exposures,experiments were performed for the GD-300 series of radiophotoluminescent glass detectors (RPLGD)and the GR-200 series of thermoluminescent detectors(TLD).X-rays and ^(137)Cs and ^(60)Coγ-rays were used to irradiate the RPLGDs and TLDs,their dose linearity,uniformity/reproducibility of signal,fading effect and energy dependence were compared.Both kinds of the detectors have generally good dosimetric properties.The dose linearity and energy dependence of the GD-351 dosimeters and the TLDs are nearly the same,but the RPLGD is much better than the TLD in terms of the uniformity and fading effect.
文摘The Delta4 3D dose verification device was commissioned in the current work for pre-treatment quality assurance (QA) of Intensity Modulated Radiotherapy (IMRT) and Volumetric Modulated Arc Therapy (VMAT) plans. The cross calibration and relative array calibration were performed to enable absolute dose comparison. The linearity of response with dose and temperature sensitivity tests were also conducted to investigate dosimetric properties of the Delta4 device. The need to modify the original CT image of the Delta4 phantom for accurate dose calculation and comparison is addressed in this work, applying a CT extension algorithm. A number of test plans varying from simple 4—field conformal to IMRT and VMAT plans were measured to evaluate the accuracy of this device. It was found that the Delta4 device measured dose accurately to within ±1%. In order to maintain this level of accuracy the machine output fluctuations need to be corrected prior to each measurement and the relative array calibration needs to be performed every six months.
文摘为了研究光释光（OSL）技术,设计了OSL剂量探测系统。采用Landauer单点剂量片作探测器,敏感材料为Al2O3：C,并在CW-OSL模式下对系统进行了本底评估、剂量线性和最小可探测剂量（MDD）测试。实验结果表明,该系统本底控制在150 cps的较低水平,处于国内领先水平;探测器经60Co标准源辐照后,在1～100 m Gy剂量范围内具有良好的线性响应;MDD为1μGy。
文摘针对国内数字电子个人剂量计种类繁多、测量原理不同导致其性能差异显著进而不利于个人剂量的有效监督的情况。按照国家标准和规程要求,设计新一代个人剂量计Nt2000,并在标准辐射场中对该仪器进行了相对固有误差、剂量线性、重复性、能量响应和角响应测试。测试结果表明：Nt2000个人剂量计主要性能指标满足国标要求,能量响应（48--1 250 ke V）优于±28%,可部分替代国外同类仪器。
