Effect of a changed temperature regime on the benthos of a norwegian regulated river

The lowermost 20 km of the River Surna, north-western Norway receives cool water during summer from a hypolimnetic release mountain reservoir. The benthic fauna is completely dominated by insects. Benthic densities immediately below the power station are much lower than at all other localities. Although benthic densities increase downstream of the power station, they never exceed the densities above. The dominant insect group, chironomids, can be divided into four categories according to their abundance and distribution above and below the power station: (1) rare or absent above, but common or abundant below; (2) abundant or common above but rare or absent below; (3) slightly less abundant below; (4) unchanged abundance. No major differences in the species composition were recorded for stonefilies, mayflies and caddisflies.     

PECVD法低温形成新型SiO_xN_y薄膜的界面特性研究

研究了等离子体增强化学气相淀积（PECVD）方法低温形成新型SIOxNy薄膜的界面特性。研究侧重于PECVDSiOxNy薄膜良好界面特性的控制，探索出界面特性与微观组份、衬底工作温度、反应室气压、退火致密、金属化后退火的相互关系。同时给出了获取界面等特性优良的PECVDSiOxNy薄膜的最优化工艺条件，并对实验结果进行了理论分析与讨论。     

用Charpy试样研究核压力容器钢的韧性转变温度曲线

用一个标准Ｃｈａｒｐｙ试样及试验过的该试样的两个半截试样所获得的８个“再造Ｃｈａｒｐｙ复合试样”评定核压力容器用Ａ５０８ＣＬ３钢冲击韧性或断裂韧性的温度转变曲线。研究结果表明，用这种方法可得到一条较为可靠而完整的核压力容器钢的冲击韧性或断裂韧性随温度的转变曲线。这相当于在核监测计划中，只需取出一个Ｃｈａｒｐｙ试样即可得到完整的材料性能曲线，这对于提高核压力容器中子辐照脆化监测的可靠性很有价值，特别是对于运行时间较长（堆芯内监测试样数量已经不多）的核容器寿命预测和安全监视尤为重要。     

红外热释电传感器的温度稳定性

本文推出红外热释电传感器的响应率与温度的函数式，并提供和分析了实验结果，理论和实验表明，热释电传感器的性能很大程度上取决于其前放级的设计水平。     

环境热释光剂量计的自辐照与温度效应

自1976年起,用环境热释光剂量计连续六年测量了原子能所内外66个点的贯穿辐射剂量。剂量计用自制热释光CaSO_4:Dy粉末,密封在有机玻璃盒内,外加1mm厚的镀铬紫铜盒。取样周期为2—3个月,每年测量4—5次。测量时,剂量计悬挂于空旷地,离地面1m高处,以防止周围建筑物的影响。     

Effect of flexibility of substructures upon thermal behaviour of spherical double layer space truss domes. Part I: Uniform thermal loading

Double layer space trusses are one of the most popular lightweight structures selected for covering large span roofs. These highly redundant and stiff structures, which consist of thousands of members and joints, are normally single structural assemblies, without expansion joints, and are thus required to be free to expand and contract without restraints. The type and properties of supports, which may permit or restrain radial movements of the structures, can greatly influence their behaviour. The aim of this study is to present an assessment of the influence of support flexibility on the behaviour of double layer space truss domes subjected to uniform thermal loading.     

On the profile of temperature dependent series resistance in Al/Si3N4/p-Si (MIS) Schottky diodes

The temperature dependence of capacitance-voltage (C-V) and conductance-voltage (G/w-V) characteristics of metal-insulator-semiconductor (Al/Si₃N₄/p-Si) Schottky barrier diodes (SBDs) was investigated by considering series resistance effect in the temperature range of 80-300 K. It is found that in the presence of series resistance, the forward bias C-V plots exhibit a peak, and experimentally show that the peak positions with a maximum at 260 K shift toward lower voltages with increasing temperature. The C-V and (G/w-V) characteristics confirm that the interface state density (N_ss) and series resistance (R_s) of the diode are important parameters that strongly influence the electric parameters of MIS structures. The crossing of the G/w-V curves appears as an abnormality compared to the conventional behavior of ideal Schottky diode. It is thought that the presence of series resistance keeps this intersection hidden and unobservable in homogeneous Schottky diodes, but it appears in the case of inhomogeneous Schottky diode. In addition, the high frequency (C_m) and conductance (G_m/w) values measured under both reverse and forward bias were corrected for the effect of series resistance to obtain the real diode capacitance.     

New ISFET interface circuit design with temperature compensation

An integrated and new interface circuit with temperature compensation has been developed to enhance the ISFET readout circuit stability. The bridge-type floating source circuit suitable for sensor array processing has been proposed to maintain reliable constant drain-source voltage and constant drain current (CVCC) conditions for measuring the threshold voltage variation of ISFET due to the corresponding hydrogen ion concentration in the buffer solution. The proposed circuitry applied to Si₃N₄ and Al₂O₃-gate ISFETs demonstrate a variation of the drain current less than 0.1 μA and drain-source voltage less than 1 mV for the buffer solutions with the pH value changed from 2 to 12. In addition, the scaling circuitry with the V_T temperature correction unit (extractor) and LABVIEW software are used to compensate the ISFET thermal characteristics. Experimental results show that the temperature dependence of the Si₃N₄-gate ISFET sensor improved from 8 mV/°C to less than 0.8 mV/°C.     

The ‘Smart’ temperature sphere: Application in rotary drum mixers

This paper demonstrates the capability of the ‘Smart’ sphere to measure a temperature which varies with axial length and time in a non-stationary system such as a rotary drum mixer. The ‘Smart’ sphere is a low-cost, low-power, small, wireless (infrared), self-equipped data logger with a built-in temperature sensor, which moves freely when introduced inside the process and measures the surrounding temperature and subsequently stores measured data in its internal memory. This data is subsequently transferred by wireless means to the computer once the sphere is recovered at the end of the process. The ‘Smart’ sphere, when introduced into the rotary drum mixer, moves with the bulk particles and measures high resolution longitudinal (axial) temperature data. Thus, the capability of free moving measurements by a ‘Smart’ temperature sphere in rotary drum mixers has been experimentally demonstrated and found satisfactory. Moreover, the ‘Smart’ sphere measurement has been compared with the fixed point measurements taken at an instant in the drum. Axial temperature variation measured by the sphere in the rotary drum experiment is in good agreement with the reference temperature measured by the temperature probe. Thus, the ‘Smart’ sphere measurement fills the gaps between the fixed point measurements and provides high resolution temperature data which could be further used for modelling and prediction of such processes.