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991.
992.
本文介绍了一种双光纤探头式浓度检测系统的工作原理和结构设计。该系统利用双光路比较电压的测量和单片机控制的数据处理系统进行浓度的实时性测量。实验结果表明,该系统具有精度高、速度快等特点,在浓度测试中具有良好的应用前景。 相似文献
993.
光电振动传感技术新进展 总被引:3,自引:0,他引:3
光电振动传感器在振动测量领域占有重要地位,概要叙述了光电振动传感器近年来的最新进展。按测量原理分类介绍了相关技术的发展和取得的成果,并对技术趋势做了总结归纳,指出了一些热点方向。 相似文献
994.
A novel method for grabbing 3D shape of an object is proposed. It uses a pair of color-coded light sources to create a 3D-coordinated illumination space. The intensities of two modulation colors are complementally balanced, which makes the sum of the intensities of the colors a constant. This method demonstrates the abilities of uniquely representing any point in the 3D-coordinated illumination space, reducing the measuring problems in blind area, and compensating the effect caused by changes of surface color and reflection. In addition, this method has the ability of acquiring the 3D shape information in parallel and the algorithm is fairly simple, so the 3D imaging speed is basically restricted by the frame rate of the color CCD camera. 相似文献
995.
碳纳米管在生物化学传感及生物传输方面的应用 总被引:2,自引:0,他引:2
碳纳米管作为一种新型一维纳米材料具有独特的结构和性质,在生物传感、生物标记及生物传榆等研究中显示了巨大的潜力.碳纳米管在化学、生物及医药方面的研究应用具有重要的理论意义及实际意义.重点综述了碳纳米管在生物化学传感和生物传榆中的研究应用进展,并展望了其发展趋势和应用前景. 相似文献
996.
A novel amperometric nitric oxide sensor with a wide linear range, low detection limit and fast response time was developed.
The sensor was fabricated using a poly-brilliant cresyl blue (PBCB)/Nafion film modified glassy carbon electrode (GCE). The
PBCB on the working GCE surface dramatically improves the oxidation response of nitric oxide and lowers the required potential
for the two-step oxidation of NO. Otherwise, Nafion coated onto the film electrode surface does not only improve the selectivity
of the sensor, but also further lowers the active energy of the direct three-electron oxidation of NO to nitrate. The effect
of the preanodic time and the film thickness of the electropolymerization on the nitric oxide response as well as the volume
of Nafion coated onto the surface and the potential for amperometric detection were optimized. This novel sensor has been
applied to the determination of NO released from rat liver cells, and the result is satisfactory.
Correspondence: Sheng Shui Hu, Department of Chemistry, Wuhan University, Wuhan 430072, P.R. China 相似文献
997.
This paper presents an optical approach to measure the oxygen gradients in biofilms grown on stainless-steel 316L. The sensor is constructed by immobilizing an oxygen-quenchable fluorophore at the tip of an optical fiber. The response time and reversibility of fiber-optic sensor have been analyzed. By mounting the optical fiber using a computerized micromanipulator, the vertical profiles of oxygen are measured with 10 μm depth resolution across biofilms on metal coupons. Steep concentration gradients of oxygen have been observed within the biofilm, both perpendicular and parallel to the metal surface. Optical response of the biofilm grown metal surface is found to be a consistent measure of the oxygen profiles within biofilms. 相似文献
998.
本文从理论上通过对钕玻璃中Nd~(3+)离子光吸收特性的分析,阐明了其光吸收对温度依从性的原因.在实验中,试制了几种不同类型的钕玻璃光纤温度传感探头.对Nd~(3+)离子光吸收的温度特性进行了验证,其结果和理论分析相一致,实验表明钕玻璃是一种性能良好的光纤温敏传感材料. 相似文献
999.
Tungsten trioxide and two types of tin dioxide were compacted at different pressures and then sintered at different temperatures
in order to study how the microstructure formed is dependent on these parameters. The structures were studied using dilatometric
and porosimetric techniques and also using electron microscopy. X-ray diffraction was used to ascertain the completeness of
the decomposition reaction of SnSO4 being converted to SnO2. Tin dioxide, which was prepared from tin sulphate by calcining, was characterised by a large specific surface area. For
all three materials studied the mean pore size was found to increase and the specific surface area was found to decrease with
increasing sintering temperature. In the case of WO3 the total pore volume decreased markedly as the sintering temperature was increased from 900 to 1000° C. However, in the
case of SnO2, the total pore volume remained almost constant in the sintering temperature range of 600 to 1500° C. In the case of SnO2 derived from SnSO4 the sintered density was about 45% of the theoretical value while for the conventionally made SnO2 the sintered density was about 55% of the theoretical value. The sintered density of WO3 was found to show a marked increase, from 55% to 70% of the theoretical value, as the sintering temperature was raised from
1000 to 1100° C. 相似文献
1000.
A novel gas-sensing system based on a dynamic nonlinear response is reported to enhance the selectivity toward sample gases using a single detector. A periodic temperature change was applied to a semiconductor gas sensor and the resulting conductance of the sensor was evaluated by fast Fourier transformation (FFT). The dynamic nonlinear response to the sample gases was further characterized depending on the frequency of the temperature change. The characteristic sensor response under the application of a temperature change was theoretically simulated by considering the kinetics of gas molecules on the semiconductor surface. 相似文献