PbCrO4-V2O5系陶瓷湿敏电阻材料初探

报导了在体控型湿敏材料ＰｂＣｒＯ４中引入Ｖ２Ｏ５的研究结果。实验表明，随着Ｖ２Ｏ５含量的增加，材料在低温范围内感湿灵敏度下降，当ＰｂＣｒＯ４与Ｖ２Ｏ５的摩尔比为１：１时，材料几乎失去感湿特性，当比例为１：０．３时，在温度为４０￣８０℃相对湿度为３０％￣９０％ＲＨ的范围内，材料的湿阻特性几乎与温度无关，据此有可能制备不加温度补偿即可直接使用的湿度传感器。     

(CoMgNi)O 系材料的高温缺陷研究

通过对（ＣｏＭｇＮｉ）Ｏ系氧敏材料的电导率与氧分压及电导率与温度的关系分析讨论了材料的氧敏机理和缺陷结构,由缺陷理论得出高温下材料的缺陷类型主要是单电离和双电离的金属缺位并导致ｐ型电导,由实验曲线得到了材料的某些参数。     

缺陷交互作用对陶瓷半导体导电性能的影响

本文借助于缺陷化学反应过程，分析了陶瓷半导体内缺陷间的交互作用，得到了陶瓷半导体实验研究的三个重要启示：（1）强还原（或氧化）或施主（或受主）掺杂对同一样品不能同时起到最佳效果；（2）本征原子空位对施主或受主的补偿导致电导率的非线性增长；（3）缺陷的缔合降低了半导化杂质的有效浓度，从而使电导性能发生异常变化。     

TiO2—V2O5—Li2O系湿敏陶瓷材料的改性研究

研究了掺杂ＺｎＯ对ＴｉＯ２－Ｖ２Ｏ－Ｌｉ２Ｏ系湿敏材料结构及性能的影响。结果表明：参杂ＺｎＯ改善了材料微结构，提高了材料的硬度，烧结温度，湿度灵敏度及稳定性，改性材料以ＴｉＯ２为主相，粒界生成ＬｉＺｎＶＯ４感湿玻璃，其中低Ｖ２Ｏ５掺杂的材料Ａ孔隙度及灵敏度较高，高Ｖ２Ｏ５掺杂的材料Ｂ固有阻值低。     

压阻式微型动态压力传感器的灵敏度温度补偿

压阻式压力传感器具有灵敏度高,体积小,使用频带宽,结构简单等特点。但也存在着受溫度影响大,需进行溫度补偿的问題。灵敏度温度补偿是其中重要的一项。补偿方法主要有以下几种: 恒流源补偿依靠电源对电流的稳定性,使传感器工作电流不受温度影响,理论上可消除温度对灵敏度的影响。当采用恒压源供电时,通常在电桥的电源廻路上进行线路补偿。按补偿元件与被补偿元     

智能一氧化碳报警器原理与设计

介绍一种新型家用的一氧化碳（ＣＯ）报警器的原理与设计。其采用ＭＯＴＯＲＯＬＡ半导体的ＭＧＳ１１００一氧化碳传感器作为ＣＯ敏感元件，辅之温度补偿，由ＭＯＴＯＲＯＬＡ半导体的ＭＣＵ６８ＨＣ０５Ｐ９进行实时控制和特性修正。文中对ＣＯ传感器温度补偿方法、ＣＯ浓度测量温度修正及环境湿度影响，进行了分析和讨论。实际调试证明，本设计也适合采用其他公司的ＣＯ传感器来进行。     

高性能磁盘阵列I/O服务时间的分析

在对常规策略的Ｉ／Ｏ服务时间进行分析的基础上,认为磁盘阵列系统中、当所有磁盘均进行Ｉ／Ｏ操作且只作一次时,系统的Ｉ／Ｏ服务时间最短,性能最佳,为此提出了一种改进策略,这种策略通过对Ｉ／Ｏ子命令进行归并,对分析数据进行调整使磁盘只作一次Ｉ／Ｏ操作最后,在实时操作系统环境下测试了一且数据,并将测试结果进行了分析比较。     

Mn（NO3）2溶液热扩散的TiO2压敏电阻—电容性能

对于Ｎｂ２Ｏ５施主掺杂的ＴｉＯ２半导瓷，掺入ＢａＣＯ３，Ｂｉ２Ｏ３可形成晶界绝缘层并可降低烧结温度，采用Ｍｎ（ＮＯ３）２溶液热扩散的方法使Ｍｎ＾２＋进入晶界可提高晶界热垒，从而提高压敏电压及非线性系数，大幅度降低介电损耗。     

闭环全光纤电流互感器温度补偿方法研究

分析了闭环全光纤电流互感器(FOCT)的温度误差影响因素,设计了FOCT系统的温度补偿方案,完成了样机研制及全温范围(-40℃～70℃)内不同长度1/4波片和不同圈数传感环的系统性能测试。仿真结果表明,当1/4波片的相位延迟角在101°～103°范围内时,1/4波片和Verdet常数对FOCT的温度误差影响可相互抵消。试验测试结果表明,当1/4波片长度在2.4mm,即1/4波片的相位延迟角为102.86°时,FOCT的温度性能最好,和仿真结果一致。     

基于PC总线模板的并联式温度补偿器件优选

并联式温度补偿具有近似性，特别是当传感器和温度补偿器件特性分散性都较大时。利用标准总线模板研制了一专用系统，该系统能对传感器和温度补偿器件进行优化组合，最大限度的改善补偿效果。     

Numerical study of hydrogen permeation flux in ytterbium doped strontium cerate and thulium doped strontium cerate (II)

This study analyses the hydrogen permeation flux model with (1) modifications in the defect concentration calculations where the concentration of substitutional cation on cerium site is utilised as the independent variable for the calculation, instead of the previous step-wise calculation with the concentration of oxygen vacancy as the independent variable and (2) the additional terms to include the oxygen partial pressure gradients for calculation of hydrogen permeation flux. The modification in the defect concentration method allows a short model simulation run time, which consequently allows incorporation of the concentration constraints in the parametric sensitivity analysis, but still produces the same set of defect concentrations as calculated in the previous methods. It is also found in this study that the discrepancy between the model and experimental results (in terms of the effect of changes in hydrogen partial pressure gradients on the hydrogen permeation flux) is not due to the influence of oxygen partial pressure gradients. Parametric sensitivity analysis shows that there is no significant difference in the sensitivity of the model by comparing Case A and B. The result of parameter tuning to predict the hydrogen permeation flux for 5% thulium doped strontium cerate in Case B shows a similar trend to the previous study (Case A). These results suggest negligible oxygen ion conductivities in these types of membrane, as reported in the literature.     

TiO2薄膜氧敏特性研究

金属氧化物随氧分压不同，有改变电导率这一性质而被广泛地用来制作氧敏传感器，传统的传感器大多是体材料或厚膜材料，工作时需加高温。本文描述的是ＴｉＯ２薄膜材料与Ｐｔ薄膜形成的肖特基势垒高度随氧分压不同而改变的氧敏现象，测定了该肖特基二极管的氧敏特性，并讨论了它的敏感机理。     

Kinetic behavior of resistive oxygen sensor using cerium oxide

In order to decrease exhaust gas emissions, oxygen gas sensors with fast response are required. We evaluated two kinds of fast response time (<1 s) for two oxygen sensors with different cerium oxide particle sizes and crystallite sizes, using two methods: the commonly used jump method and the so-called dynamic method. The dynamic method consists of comparing the amplitude of oxygen partial pressure with that of the sensor output, following the changes in oxygen partial pressure produced by periodic modulation of the hydrostatic pressure with the composition of the atmosphere kept constant. The response times obtained with the jump method and dynamic method are defined as t₉₀ and t_b, respectively. Further, we evaluated the relationship between the amplitude magnitude of the oxygen sensor output (A_n) and the frequency of the oxygen partial pressure (f), using the dynamic method. The results obtained were as follows. The value of t_b for the oxygen sensor with a crystallite size and grain size of about 100 nm was 134 ms or less at 1173 K. The value of t₉₀ was 20 and 1 ms when the oxygen partial pressure changed from high to low and from low to high, respectively. From a plot of log A_n versus log f, it was concluded that the kinetics of a sensor using cerium oxide with crystallite and grain sizes from 100 to 300 nm were controlled by diffusion when the oxygen partial pressure was periodically changed in the shape of a sine wave. It was found that the newly developed equipment was able to evaluate two kinds of response times less than 50 ms.     

高温压力传感器温度漂移补偿研究

针对高温压力传感器耐高温和高压的测量的要求,设计了压阻式压力传感器硅杯式芯片版图,采用SIMOX(separationbyimplantedoxygen)技术SOI(silicononinsulator)晶片,在微加工平台上制作了该芯片,获得了差动等臂等应变的惠斯登检测电桥。对采用耐高温封装后的传感器的热零点漂移、热灵敏度漂移和零位输出的补偿作了研究,设计了补偿电路,推导了热灵敏度漂移补偿的计算公式,在通用型高温压力传感器的研发中证明其可行性和实用性,并总结出了经验公式。     

Improving Blood Compatibility of Intravascular Oxygen Sensors Via Catalytic Decomposition of S-Nitrosothiols to Generate Nitric Oxide In Situ

Reliable, real-time, in vivo sensing (intravascular) of blood gases and electrolytes remains a difficult challenge owing to biocompatibility issues that occur when chemical sensors are implanted into the blood stream. Recently, local release of nitric oxide (NO) at the sensor/blood interface has been suggested as a potential solution to this problem. However, the lifetime of NO release from thin polymer films coated on implanted sensors is limited by the reservoir of NO donor loaded within the polymeric coating. To continuously produce NO at the sensor/blood interface, a novel approach to catalytically decompose endogenous S-nitrosothiols (RSNOs) in blood to generate NO in situ is reported herein. Metallic copper particles of two different sizes (3 μm and 80 nm) are embedded as catalysts in thin polymer coatings on the surface intravascular electrochemical oxygen sensing catheters. Oxygen levels (partial pressure of oxygen; PO(2)) provided by the copper particle/polymer coated sensors are, on average, more accurate than values obtained from non-NO generating control sensors when both types of sensors are implanted in porcine arteries for 19-20 h. Upon termination of each in vivo study, catheters were explanted and examined for surface thrombosis via both visual image and lactate dehydrogenase (LDH) assay. The results indicate that the Cu(0)-catalyst coatings significantly reduce the occurrence of surface thrombosis, likely from the ability to generate NO from endogenous RSNO species at the sensor/blood interface.     

变频式氧传感器输出特性的研究

介绍了一种新式氧化锆固体电解质变频式氧传感器,其结构由敏感电池和氧泵两部分复合构成。理论推导在浓差电势E1~E2范围的响应时间t与被测氧分压p1呈正比关系。实验测试数据显示:在保持浓差电势E1,E2在均不超过200 mV的范围时,时间t与被测氧分压p1之间的确呈现出非常好的正比关系,线性相关系数R均大于0.986。但当电势E1,E2超过200mV后,实验结果却与理论严重不符。经过初步分析,当浓差电势超过一定值后,空腔内的较低氧分压改变了固体电解质性质,使氧泵的电导率发生了变化导致理论推导的偏差。     

Temperature compensation of fluorescence intensity-based fiber-optic oxygen sensors using modified Stern–Volmer model

In practical sensing applications, temperature effects are of particular concern, and hence it is necessary to develop the means to correct the fluorescence intensity measurement in accordance with the working temperature. Accordingly, this study develops a modified Stern–Volmer model to compensate for the temperature drift of oxygen concentration measurements obtained using fiber-optic sensors. The oxygen sensors considered in this study are based on teraethylorthosilane (TEOS)/n-octyltriethoxysilane (Octyl-triEOS) or n-propyltrimethoxysilane (n-propyl-TriMOS)/3,3,3-trifluoropropyltrimethoxysilane (TFP-TriMOS) composite xerogels doped with platinum meso-tetrakis(pentafluorophenyl)porphine (PtTFPP).

The experimental results are fitted to the modified Stern–Volmer model in order to compute suitable values for a temperature compensation coefficient at different working temperatures. It is found that the proposed temperature compensation method reduces the difference in the oxygen concentration measurement for working temperatures in the range of 25–70 °C as compared to data without compensation. The linearity and sensitivity of PtTFPP-doped n-propyl-TriMOS/TFP-TriMOS sensor are better than PtTFPP-doped TEOS/Octyl-triEOS sensor for working temperatures in the range of 25–70 °C.

The proposed approach could provide a straightforward and effective means of improving the accuracy of fiber-optic oxygen sensors if a variable attenuator is designed according to the temperature compensation coefficient. Thus, the fiber-optic oxygen sensor with a variable attenuator could work in a broad temperature range without using a temperature sensor.     

液体电解质氧传感器输出特性研究

对液体电解质氧传感器在不同氧体积分数、氧分压下的输出特性进行研究.测量氧传感器在不同氧体积分数、氧分压下的输出值,利用最小二乘法对输出值进行处理,得到氧传感器的输出特性曲线.对特性曲线进行分析,结果表明:液体电解质氧传感器对氧体积分数、氧分压的测量具有良好的线性度.压力冲击对传感器工作电极造成损害从而影响传感器性能,加入粉末冶金层能够克服这一问题,但传感器的响应时间有所增长.     

醋酸-水团簇中氢键作用的初步研究

介绍Gaussian94对nCH3COOH-H2O团簇体系进行的研究。对若干构型在6－31g和6－31 g（d,p）基组下进行了结构优化和相互作用能计算，并对氢键成键情况作了初步探讨。