A hybrid radiation detector for simultaneous spatial and temporal dosimetry

In this feasibility study an organic plastic scintillator is calibrated against ionisation chamber measurements and then embedded in a polymer gel dosimeter to obtain a quasi-4D radiation detector. This hybrid dosimeter was irradiated with megavoltage x-rays from a linear accelerator, with temporal measurements of the dose rate being acquired by the scintillator and spatial measurements acquired with the gel dosimeter. The detectors employed in this study are radiologically equivalent; and we show that neither detector perturbs the intensity of the radiation field of the other. By employing these detectors in concert, spatial and temporal variations in the radiation intensity can now be detected and gel dosimeters can be calibrated for absolute dose from a single irradiation.     

A high resolution spatial population database of Somalia for disease risk mapping

Background  

Millions of Somali have been deprived of basic health services due to the unstable political situation of their country. Attempts are being made to reconstruct the health sector, in particular to estimate the extent of infectious disease burden. However, any approach that requires the use of modelled disease rates requires reasonable information on population distribution. In a low-income country such as Somalia, population data are lacking, are of poor quality, or become outdated rapidly. Modelling methods are therefore needed for the production of contemporary and spatially detailed population data.     

微机化神经感觉探测仪的研制

本文介绍了一种微机化神经感觉探测仪。它通过光电压力传感器实时测量动物或人体肢体对压力的反应灵敏度，适用于神经感觉类及＂医学行为学＂方面疾病的诊断和医学科学实验研究。     

微机腹力探测仪的研制

本文介绍了一种微机腹力探测仪。它通过复合式传感器实时测量腹壁变形量及反弹力，经单片微机数据处理后打印腹力等级的判断结论及原始测量数据表。试用表明，该机有助于腹诊水平的提高。     

A fast, high spatial resolution optical tomographic scanner for measurement of absorption in gel dosimetry

A fast tomographic optical density measurement system has been constructed and evaluated for application in Fricke 3D gel dosimetry. Although the potential for full three-dimensional radiation dosimetry with Fricke gel dosimeters has been extensively reported, its application has been limited due to a lack of fast optical density measurement systems. In this work, the emphasis of the design has been to achieve a short scan time through the use of precision optics and minimal moving parts. The system has been demonstrated in the laboratory to be able to achieve better than 1mm resolution and a scanning time per tomographic slice of 2.4 seconds. Full volumetric sampling of a 10 cm diameter by 7cm long cylinder can be achieved in 3 minutes. When applied with a Fricke based gel dosimeter a linear response between reconstructed CT number and absolute dose was better than 3%.     

饮用水中16种多环芳烃的高效液相色谱-荧光-二极管阵列同时测定法

目的建立饮用水中16种多环芳烃(PAHs)的高效液相色谱-荧光-二极管阵列(HPLC-FLD-DAD)同时测定法。方法将1 L水样经Bond Elut Plexa固相萃取柱吸附,二氯甲烷和乙酸乙酯洗脱,洗脱液经氮吹后用乙腈定容至0.5 ml,经0.45μm滤膜过滤,用Pursuit PAHs色谱柱分离,柱温30℃;用乙腈-水作流动相梯度洗脱,流速为1.8 ml/min;FLD采用波长切换方式测定萘、苊、菲、芴、蒽、荧蒽、芘、苯并[a]蒽、苯并[b]荧蒽、苯并[k]荧蒽、苯并[a]芘、二苯并[a,h]蒽、苯并[g,h,i]苝、茚并[1,2,3-cd]芘15种PAHs,DAD采用254 nm波长检测苊烯;进样体积为5.0μl。结果在0.000 5~100 mg/L的线性范围内,16种PAHs的回归方程均呈较好的线性关系(r0.998)。本方法的检出限为0.04~0.50 ng/L,定量下限为0.13~1.67 ng/L;日内和日间RSD分别为1.0%~3.1%和1.5%~3.8%;加标回收率为77.7%~96.9%,加标RSD为1.1%~4.2%。结论该方法快速、准确、灵敏,适用于饮用水中16种PAHs的测定。     

A study of spatial resolution in pollution exposure modelling

Background  

This study is part of several ongoing projects concerning epidemiological research into the effects on health of exposure to air pollutants in the region of Scania, southern Sweden. The aim is to investigate the optimal spatial resolution, with respect to temporal resolution, for a pollutant database of NO_x-values which will be used mainly for epidemiological studies with durations of days, weeks or longer periods. The fact that a pollutant database has a fixed spatial resolution makes the choice critical for the future use of the database.     

二极管阵列检测器和荧光检测器联合测定饮用水中多环芳烃

目的:探讨二极管阵列检测器(DAD)和荧光检测器(FLD)联用,高效液相色谱法测定饮用水中多环芳烃的应用。方法:进行二极管阵列检测器(DAD)和荧光检测器(FLD)联用分离条件和样品处理试验,得出最佳色谱条件。结果:选定条件下,6种多环芳烃在测定范围内线性关系良好,相关系数0.9935~0.9999;荧蒽、苯并(b)荧蒽、苯并(k)荧蒽、苯并(a)芘、苯并(ghi)芘、茚(1,2,3-CD)芘方法检出限分别为1.40,1.73,1.01,2.46,1.83,8.28(ng/L);回收率70%~110%。结论:DAD和FLD联用具有较强定性能力,重现性好,灵敏度高,成功应用于饮用水中多环芳烃监测。     

CT图象空间分辨率影响因素的理论研讨

详述了描述空间分辨率的方法，并对影响CT图象空间分辨率的主要因素进行了理论研讨。     

Design and characteristics of a scintillation gamma camera with high spatial resolution and fast response

The second generation of the scintillation gamma camera gamma KC-2 has been recently produced in lots. Compared to the first Soviet model gamma KC-1 it features advanced spatial resolution, maximum count rate, and image uniformity. A built-in microprocessor controls in real time corrections for distortions thus providing a marked gain in serviceability and expanded diagnostic capacity.     

煤工尘肺胸膜病变的高分辨率CT形态学表现及其诊断价值

目的　通过煤工尘肺胸膜病变的CT和高分辨率CT(HRCT)检查研究煤工尘肺胸膜病变的可靠的诊断技术。方法　煤矿井下采掘混合工煤工尘肺患者 13 1例 (其中 ,0 14例、Ⅰ期 46例、Ⅱ期 58例、Ⅲ期 13例 )及对照组 2 0例 (均摄有同期高仟伏胸片 ) ,在胸部常规CT扫描后 ,另在 4个固定水平上及感兴趣区加作HRCT扫描 ,而后进行观察对比研究。结果　参照国家尘肺诊断标准中对胸膜病变 -胸膜斑的判定方法 ,共发现胸膜病变者 68例 (51.91% ) ,其中 ,尘肺Ⅰ期 12例 (17.65% )、Ⅱ期 43例 (63 .2 4% )、Ⅲ期 13例 (19.12 % )。据胸膜病变在HRCT的形态表现可分为 :结节型(73 .3 8% )、扁平型 (18.71% )、不规则型 (7.91% )、混合型 ;病变位于胸壁胸膜者占 65.0 2 %、纵隔面占2 2 .16%、心包占 12 .80 %。本组病例肺尖和肋膈角区均未见受累表现 ,胸膜病变厚度以 5～ 10mm者为多见 (88.17% )。结论　煤矿工人胸膜损害并非罕见。HRCT是显示胸膜病变的可靠检查方法 ,是常规CT的补充手段 ,具有重要的诊断和实用价值 ,但需进一步进行影像学与病理学的对照研究     

饮料中色素含量的高效液相色谱-二极管阵列测定法

目的建立高效液相色谱仪-二极管阵列检测器测定饮料中的5种色素的方法。方法用Inertsil ODS-SP色谱柱(250 mm×4.6 mm,5μm),以0.02 mol/L的乙酸铵-甲醇为流动相,梯度洗脱,柱温30℃,二极管阵列检测器在波长460 nm处进行检测。结果 5种人工合成色素在浓度0.25~10 mg/L范围内线性关系良好,回归系数均0.999,相对标准偏差(RSD)为1.45%~4.21%。5种色素的最低检出限范围为0.05~0.09 mg/kg,平均加标回收率范围为92.3%~100.7%。结论该方法方便简单,样品分析时间短,具有较高的样品回收率和较低的检出限,可用于食品安全风险监测的样品测定。