关于叶绿素a测定萃取时间的探讨

在叶绿素a的测定过程中，萃取时间长短对测定结果产生影响，得出了萃取时间5小时可满足叶绿素a测定要求的结论。     

Use of diffuse reflectance spectrometry in spot test reactions for quantitative determination of cations in water

Diffuse reflectance spectroscopy can be successfully used for the quantitative determination of small amounts of pollutants like metals. The remission function was found to be linearly proportional to the concentration, when we applied the Kubelka–Munk equation. The color reactions of Cu(II), Co(II), and Ni(II) with dithiooxamide, were realised on filter paper. Reaction between Fe(III) and ammonium thiocyanate was realized on filter paper and gelatine matrix. All measurements were accomplished with a laboratory-constructed reflectometer. We have obtained a calibration curve by plotting the optical density of reflectance A_R vs log of the mol l⁻¹ concentration. Limits of detection at the 10⁻⁴ M level were estimated for all the compounds. Linear dynamic range extend over one order of magnitude and shows the potential of device for the quantitative analysis of environmental pollutants.     

用于汽车安全气囊的气体发生器产气性能研究

建立了模拟汽车碰撞过程的实验系统;利用该系统模拟汽车碰撞时产生的撞击信号触发气体发生器开始工作,对模拟安全气囊的密闭、定容积的充气筒内产生的p-t曲线、气体发生器内部的p-t曲线、撞击时产生的a-t曲线进行测试并得到相关测试参数值;从而对气体发生器的产气性能进行研究。测试结果表明,温度对安全气囊的工作有一定影响。利用该测试系统测试得到的数据与美国BREED公司对同类产品的测试结果比较,有很好的相比性,测得的数据可作为气体发生器生产质量的检验依据。     

基于超声脉冲法的火灾损伤后混凝土裂纹深度检测

检测或诊断裂纹深度是火灾后混凝土结构受损综合评判的重要依据。开发一种专用的火灾后混凝土裂纹深度检测仪器,是一项填补国内该领域空白的重要研究课题。在研讨和分析超声脉冲法检测混凝土表面损伤裂纹深度的单面平测法、逐层穿透法和损伤层厚度判定3种测试方法的基础上,笔者设计开发了一种超声测试诊断仪,采用高精度计时电路、传感器驱动电路和自动增益电路,提高了仪器计时精度和抗干扰性。经对多组火灾损伤后的结构混凝土试件的测试,获取了6组共60个声时数据,用给出的方法进行了计算,得出的裂纹深度值与观察结果能较好地吻合。理论与实测表明,提出的裂纹检测方法和开发出的测试仪器具有实用性。     

苏南地区新近沉积土的动剪切模量比与阻尼比--试验研究

苏南地区的场地土主要为漫滩相、湖沼相或冲湖相新近沉积软弱土，结构松散，沉积零乱，成分复杂，饱水可液化粉细砂层及粉土层较为发育，在地震或动力荷载的作用下有可能发生软土震陷或砂土液化。通过对苏南地区淤泥质粉质粘土、粘土、粉质粘土、粉质粘土与粉细砂互层土、粉土、粉砂、细砂和中粗砂等8类新近沉积土155个原状土样历时4年的试验研究，给出了该地区上述8类新近沉积土的动剪切模量比G／Gmax和阻尼比D随剪应变幅值γ变化的平均拟合曲线及其参数的推荐值。为便于一般工程应用，给出了这8类新近沉积土的G/Gmax-γ，和D—γ关系曲线的推荐值及其标准差。     

深部岩体分区破裂化模拟试验模型几何尺寸的确定

为了揭示深部岩体在开挖时所发生的一系列变化情况,需要进行模拟试验研究。简要介绍了深部岩体在开挖洞室或巷道时发生的分区破裂化现象及其发展规律。根据分区破裂化力学现象、模拟试验背景和试验加载条件,运用弹性力学的基本理论,通过分析与计算,确定了采用b/a≥10作为模型几何参数的选取原则。在实验室条件下,可以采用石膏半径b=1 000 mm,钻孔半径a=100 mm的圆柱体模型来模拟深部岩体的分区破裂化现象及其规律。     

Effects of a tropical cyclone on the drinking-water quality of a remote Pacific island

The effect of a cyclone (Ami, January 2003) on drinking-water quality on the island of Vanua Levu, Fiji was investigated. Following the cyclone nearly three-quarters of the samples analysed did not conform to World Health Organisation (WHO) guideline values for safe drinking-water in terms of chlorine residual, total and faecal coliforms, and turbidity. Turbidity and total coliform levels significantly increased (up 56 and 62 per cent, respectively) from pre-cyclone levels, which was likely due to the large amounts of silt and debris entering water-supply sources during the cyclone. The utility found it difficult to maintain a reliable supply of treated water in the aftermath of the disaster. Communities were unaware they were drinking water that had not been adequately treated. Circumstances permitted this cyclone to be used as a case study to assess whether a simple paper-strip water-quality test (the hydrogen sulphide, H(2)S) kit could be distributed and used for community-based monitoring following such a disaster event to better protect public health. The H(2)S test results correlated well with faecal and total coliform results as found in previous studies. A small percentage of samples (about 10 per cent) tested positive for faecal and total coliforms but did not test positive in the H(2)S test. It was concluded that the H(2)S test would be well suited to wider use, especially in the absence of water-quality monitoring capabilities for outer island groups as it is inexpensive and easy to use, thus enabling communities and community health workers with minimal training to test their own water supplies without outside assistance. The importance of public education before and after natural disasters is also discussed.     

霉菌试验技术分析与探讨

分析了霉菌试验技术对试验结果的影响,并从试验菌种、霉菌孢子、灭菌方法以及试验结果评定等方面对提高霉菌试验结果的可靠性进行了深入探讨.     

人工加速老化测试--氙灯试验箱

讨论两种常见的、不同类型、测试条件一致的氙灯试验箱。详述了其不同的配置对光谱、辐照度控制、过滤器类型、潮湿、湿度控制、温度控制和校准等的影响。阐述了样品安置、设备的维护保养等实际操作方面的问题以及老化测试标准。     

彗星试验的改良及其在工业废水监测中的应用

为了探讨彗星试验在工业废水监测中的应用,本文将常规的细胞暴露方式改良为浸泡染毒,既提高了实验的敏感性,又使得该试验直接用于监测工业废水的遗传毒性成为可能．作者用改良彗星试验直接检测了几种工业废水所引起的V79细胞DNA损伤．结果表明,所测的各种工业废水均含有DNA损伤剂,能够诱发培养的V79细胞DNA链断裂,其中以制革厂废水的DNA损伤作用最强．本研究显示出改良彗星试验在综合评价各种废水遗传毒性方面的广阔应用前景．