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将纯聚乙烯醇(PVA)和掺有维生素C的PVA作为敏感试剂,通过旋转甩涂法分别研制出了PVA薄膜/锡掺杂玻璃光波导元件和VC-PVA薄膜/锡掺杂玻璃光波导元件并检测其气敏特性.实验结果表明,PVA薄膜/锡掺杂玻璃光波导元件对二甲苯气体有良好的选择性响应,其响应浓度范围为10-4~10-7(体积比);加入VC后,使此敏感元... 相似文献
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以FeSO4.7H2O,H3PO4,LiOH.H2O,AgNO3及Y(NO3)3.6H2O为原料,利用水热法一步合成出了LiFe1-0.01xY0.005xAg0.005xPO4粉体(x=0.5,1.0),并将该材料作为敏感试剂,用旋转-甩涂法做成纳米薄膜固定在锡掺杂玻璃光波导表面,在不同温度下进行热处理。采用紫外-可见分光光度计、测厚仪以及自组装的玻璃光波导气敏测试仪研究了热处理对LiFe1-0.01xY0.005xAg0.005xPO4薄膜光学及气敏特性的影响。研究结果表明:在450℃下进行热处理的薄膜元件具有良好的光学透明及较好的气敏特性。相同浓度的不同挥发性有机气体中,该传感元件对二甲苯气体有很好的选择性响应,其检测响应范围为1×10-7~1×10-3(V/V),响应-恢复时间分别小于5和100 s。 相似文献
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为提高LiFePO_4敏感薄膜元件的灵敏度,以铂(Pt)作为掺杂元素,用水热法一步合成出LiFe_(0.98)Pt_(0.02)PO_4粉末;利用旋涂法将其固定在锡掺杂玻璃光波导表面,制备了LiFe_(0.98)Pt_(0.02)PO_4薄膜/锡掺杂玻璃光波导元件。将敏感薄膜在不同温度下热处理,通过比较各个敏感薄膜元件对苯类挥发性有机气体的响应讨论薄膜处理温度对LiFe_(0.98)Pt_(0.02)PO_4薄膜元件光学特性及气敏性的影响。结果显示,在450℃下处理的薄膜因具有光学透明性好、折射率高、光传播损失小等特点对苯类气体显出较大的响应,能够检测出浓度为1×10~(-7)~1×10~(-3)V/V_0的二甲苯气体。当气体浓度小于1×10~(-6)V/V_0时,其他苯类气体不会对二甲苯的检测产生影响。 相似文献
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用溶胶-凝胶法制成了NiO掺杂的ZnFe2O4溶胶,并用浸渍提拉法将其固定在锡掺杂玻璃光波导表面,研制了NiO-ZnFe2O4复合薄膜/锡掺杂玻璃光波导气敏元件,并对无机有毒气体进行了检测。 实验结果表明,在室温下,该传感元件对H2S气体具有一定的选择性响应,而对相同浓度的其它无机气体的响应相对较小,能够检测到1.0×10-9(体积比)的H2S气体,其响应和恢复时间分别是6和8 s。 该元件具有灵敏度高、响应-恢复快、可逆性和重复性好、容易制备,在室温下便于操作等特点。 相似文献
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《化学研究与应用》2015,(10)
将水热合成的Li Fe1-0.01xNi0.01xPO4(x=0.5,1.0)粉体作为敏感试剂,用旋转-甩涂法涂于锡掺杂玻璃光波导表面,在不同温度下进行热处理。采用紫外-可见分光光度计,测厚仪和平面玻璃光波导气敏测试系统(自组装)研究了薄膜干燥温度对Li Fe1-0.01xNi0.01xPO4薄膜光学及气敏特性的影响。研究结果表明,450℃下干燥的薄膜具有良好的光学透明性并对应的敏感元件显出良好的气敏特性。相同浓度的不同挥发性有机气体中,Li Fe0.99Ni0.01PO4传感元件对二甲苯气体有较大的响应,其检测响应范围为1×10-7~1×10-3(V/V0),响应-恢复时间分别小于5s和70s。 相似文献
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偶氮苯-PVP复合薄膜光波导传感器检测苯乙烯 总被引:1,自引:0,他引:1
将掺杂偶氮苯(Azo)的聚乙烯吡咯烷酮(PVP)作为敏感试剂,利用旋转甩涂法将其固定在钾离子(K+)交换玻璃光波导表面,研制了Azo-PVP复合薄膜/K+交换玻璃光波导气敏元件,并对其气敏特性进行研究。实验结果表明,该敏感元件对苯乙烯蒸汽有较好的选择性响应,其最低检测浓度为1.0×10-8体积比(V/V0),响应-恢复时间分别为9 s和24 s。在浓度1.0×10-81.0×10-3(V/V0)范围内,气体浓度与输出光强度之间有较好的线性关系。 相似文献
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采用浸渍-提拉法,将铁酸锌溶胶固定在锡掺杂玻璃光波导元件表面,通过不同的热处理温度(400℃,500℃,600℃)得到ZnFe2O4薄膜/锡掺杂玻璃复合光波导敏感元件,且对低浓度的苯乙烯蒸汽进行检测。在500℃热处理的传感元件对苯乙烯(相同浓度的挥发性气体中)的响应较大,并在体积比2.0×10-10~2.0×10-6范围内有较好的响应。响应时间和恢复时间分别为17s和60s。 相似文献
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This paper compares three methods for natural gas dehydration that are widely applied in industry:(1) absorption by triethylene glycol, (2) adsorption on solid desiccants and (3) condensation. A comparison is made according to their energy demand and suitability for use. The energy calculations are performed on a model where 105 Nm3/h water saturated natural gas is processed at 30 °C. The pressure of the gas varies from 7 to 20 MPa. The required outlet concentration of water in natural gas is equivalent to the dew point temperature of -10 °C at gas pressure of 4 MPa. 相似文献
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本文采用低温气相色谱法分析了火焰气体的成份和深度,色谱柱固定相为PoraparkQ,柱温范围-99-250℃氦气作载气。在所选择的实验条件下,火焰气体中的N2和O2有效地得到分离,可迅速精确地分析确定N2的浓度以及其他成份和浓度。 相似文献
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A novel correlation for estimation of hydrate forming condition of natural gases 总被引:1,自引:0,他引:1
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An inherent problem with natural gas production or transmission is the formation of gas hydrates, which can lead to safety hazards to production/
transportation systems and to substantial economic risks. Therefore, an understanding of conditions where hydrates form is necessary to
overcome hydrate related issues. Over the years, several models requiring more complicated and longer computations have been proposed for
the prediction of hydrate formation conditions of natural gases. For these reasons, it is essential to develop a reliable and simple-to-use method
for oil and gas practitioners. The purpose of this study is to formulate a novel empirical correlation for rapid estimation of hydrate formation
condition of sweet natural gases. The developed correlation holds for wide range of temperatures (265–298 K), pressures (1200 to 40000 kPa)
and molecular weights (16−29). New proposed correlation shows consistently accurate results across proposed pressure, temperature and
molecular weight ranges. This consistency could not be matched by any of the widely accepted existing correlations within the investigated
range. For all conditions, new correlation showed average absolute deviation to be less than 0.2% and provided much better results than the
widely accepted existing correlations. 相似文献
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Estimating the feasibility of acid gas geological disposal requires the knowledge of the water content of the gas phase at moderate pressures and temperatures (typically below 50 MPa, below 380 K) and up to 6 mol NaCl. In this paper, a non-iterative model is developed to predict the water content of sour and acid gases at equilibrium with pure water and brine. This model is based on equating the chemical potential of water and using the modified Redlich–Kwong equation of state to calculate the fugacity of the gas phase. The water content of pure CH4, CO2 and H2S are represented with average absolute deviations of less than 3.36, 7.04 and 8.4%, respectively. Experimental data of the water content of mixtures of the acid gases were reproduced with average absolute deviations of less than 6.32%. 相似文献
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Catherine M. Zimmerman William J. Koros 《Journal of Polymer Science.Polymer Physics》1999,37(12):1235-1249
Despite efforts by the membrane community to develop polymeric materials with improved O2/N2 separation performance, limited progress has occurred for almost a decade. Molecular sieving media, which can exhibit gas separation properties superior to polymers, tend to be brittle and uneconomical to produce for large‐scale membrane separation processes. Considering this, the polymer structures investigated in this work were designed to mimic aspects of the structure of molecular sieving media such as zeolites and carbon molecular sieves while maintaining the processability associated with polymers. Significantly attractive gas separation material properties were obtained using hyper rigid polypyrrolone copolymers with controlled packing disruptions between flat, packable segments. The gas transport properties in the materials changed dramatically as a result of different average interchain spacing. Moreover, all of the polypyrrolones studied in this work exhibited performance lying on or above the existing O2/N2 upper bound trade‐off line between permselectivity and permeability. These results, therefore, may point the way to a new cycle of membrane materials improvements for gas separations. © 1999 John Wiley & Sons, Inc. J Polym Sci B: Polym Phys 37: 1235–1249, 1999 相似文献
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气敏传感器已在生物、化学、航空、军事等领域获得了广泛的应用。鉴于WO3基气敏传感器是检测H2S、NOx、O3和NH3等气体最有前景的新型氧化物气敏传感器之一,本文以不同的敏感气体为分类依据系统阐述了近年来WO3基气敏传感器的研究进展,详细探讨了制备方法及贵金属掺杂对上述各种气体气敏性能的影响,并指出了目前WO3基气敏传感器在研究过程中存在的问题。 相似文献
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