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161.
煤气部分返回炼焦过程焦炭脱硫   总被引:3,自引:2,他引:3  
将半焦中的硫区分为无机硫和有机硫,在不同气氛和温度下进行脱硫实验;计算煤气返回对焦炉温度的影响和模拟炼焦过程返回煤气在炭化室的分布。结果表明:增加氢气浓度对有机硫和无机硫的脱除都有利,但是温度升高并不总是有利于脱硫;氢气脱硫效果要好于甲烷和一氧化碳;指出了炼焦后期在焦炉煤气返回之前预热煤气可以减少对炉温的影响,但是煤气的预热温度不能太高,否则甲烷裂解容易堵塞管道;煤气的最佳返回时机是在焦炭中孔隙分布较为均匀之时。  相似文献   
162.
A method has been developed for highly sensitive determination of haloperidol in human serum involving a simple extraction procedure followed by gas chromatographic separation. Target components were separated from the extracting solvents with a Van den Berg type solventless sample injector before introduction Into a DB-1 capillary separation column. A surface ionization detector (SID), which has highly selective sensitivity for Substituted amines, was employed for quantitation using bromperidol as an internal standard. Chloroform proved to be the best extracting solvent, yielding a quantitative detection limit of 5 ng/ml (S/N = 2). Comparison of the response to target compounds obtained by the SID, FTD (flame thermionic detector), and FID (flame ionization detector) showed the SID to be superior.  相似文献   
163.
陈朝方  李忠  郭建  罗玉玮 《色谱》2002,20(3):272-273
 建立了气相 质谱联用 (GC/MS)测定苯乙烯中阻聚剂对叔丁基邻苯二酚含量的方法。苯乙烯样品直接进样 ,通过毛细管柱 (HP 1,30m× 0 32mmi.d .× 0 2 5 μm)分离 ,由电子轰击 (EI)源于选择离子监测 (SIM)模式下进行检测。结果表明 ,对叔丁基邻苯二酚含量在 5mg/kg~ 5 0mg/kg时线性关系良好 (r2 =0 9987) ,回收率高 ;与美国材料测试标准ASTMD4 5 90中的分光光度测量法比较具有操作简捷、准确度高的特点。  相似文献   
164.
J. U. Keller 《Adsorption》1995,1(4):283-290
The gas adsorbed on the inner surface of a highly porous material like activated carbon or zeolite can be measured by slow damped oscillations of a torsional pendulum. The physical principles and the theory of this method are outlined. Formulas are given relating the increase in mass due to adsorption to changes of the frequency and the logarithmic decrement of slow, damped rotational oscillations of the pendulum. Preliminary measurements of gas adsorption equilibria of nitrogen on activated carbon show that the ratio of the mass adsorbedm, to the mass of the adsorbentm s , can be determined by this method with mean absolute error |m/m s |0.04%.Dedicated to the memory of Joseph Kestin (1913–1993).  相似文献   
165.
八—4—(四氢糠氧基)双酞菁衍生物钕(Ⅲ)、铕(Ⅲ)的合成和LB膜的气敏性张引*辛春梅王丹(吉林省教育学院化学系,长春130022)梁冰洁**陈文启席时权(中科院长春应用化学研究所,长春130022)关键词:希土双酞菁衍生物LB膜气敏性荧光性紫外可见...  相似文献   
166.
氧化锌脱硫中氢和氧的双气氛效应及动力学研究   总被引:4,自引:0,他引:4  
用热重法研究了氧化锌脱硫中氢氧的气氛效应以及氢氧共同存在下氧化锌脱硫的微观动力学行为。实验温区为200 ℃~320 ℃,氧化锌粒度为100目~120目。研究结果表明,在0%~40%的体积浓度范围内,氢可促进脱硫反应进行;氧则由于会引起氧化锌表面析硫使得脱硫过程随其浓度的变化复杂化。氢氧双气氛下,氧化锌脱硫动力学行为可用改良收缩核模型进行描述,表面反应活化能和固体扩散活化能分别为14.96 kJ/mol和46.77 kJ/mol。  相似文献   
167.
普鲁士蓝化合物的热分解过程,可分为三个阶段:(1)脱水;(2)Fe3+还原至Fe2+;(3)C≡N-键的断裂。H2气中的热分解由于发生了一系列的加氢反应,分解产物及所对应的分解温度都不同于He气中的情况,其产物的种类增加,C≡N-键的断裂温度降低。普鲁士蓝化合物中,CN-呈典型的双端基配位,可看作是一种双金属配位的活化模型,与CN-呈单端基配位的K3[Fe(CN)6]相比,C≡N-键的活化程度增加,不仅断裂温度降低,且能发生更深度的加氢反应。  相似文献   
168.
A nanostructural approach to analysis of proton ordering in gas hydrate cages has been worked out within the framework of the topological model of strong and weak H-bonds. The approach involves rejection of the periodic boundary conditions, decomposition of the H-bond net into spherical layers, and two-dimensional drawing of the structure of spherical (spheroidal) fragments in the form of conjugate Schlegel diagrams. To analyze proton ordering in the spherical fragments composed of gas hydrate voids, we used the simulated annealing procedure and the correlation extension method proposed earlier.  相似文献   
169.
《Electroanalysis》2003,15(18):1453-1459
A novel method for fabricating a micro gas sensor film on an indium tin oxide (ITO) electrode patterned using micro‐machining technology was developed. A micromanipulation system equipped with a counter electrode (Au; Ø10 μm) and a microsyringe, which was connected to a microinjection system, was first constructed. With this system, micro gas sensor arrays could be successfully prepared on ITO electrodes. Two kinds of micro gas sensor films were prepared, based on polythiophene (PTh) and poly(3‐n‐dodecylthiophene) (PD). The response behavior of conventional PTh and micro‐PTh films against NH3 at three different operating temperatures (25, 40 and 60 °C) was investigated by measuring the resistance of the film. With the micro‐PTh film, a reversible response was observed against NH3 when measured at 40 and 60 °C. In addition, the responsive characteristics of the microsensor films against different testing gases were examined at the three operating temperatures. The resistance of the microsensor films of PTh and PD changed considerably, depending on the type of testing gas, allowing these sensor films to be used for the detection of various gases. Furthermore, the microsensor films had a high stability compared with conventional films prepared from the same polymer.  相似文献   
170.
Many countries allow the treatment of foods with low doses of ionizing radiation to reduce microbial and insect infestations, inhibit maturation, and extend shelf life. Therefore, a reliable method is needed to identify irradiated foods and to determine their compliance with respect to allowable absorbed radiation dose. Several approaches for the identification of irradiated foods have been developed such as measurement of radiolytic products, chemiluminescence, and thermoluminescence, and the use of electron spin resonance spectroscopy to measure free radicals trapped in bone. A method for the determination of radiolytically produced hydrocarbons was developed in our laboratory to evaluate the utility of monitoring these compounds as indicators of food irradiation. The method involves the extraction of the radiolytic hydrocarbons from foods and their quantitation by gas chromatography. Concentrations of the radiolytically produced hydrocarbons increased linearly with radiation doses ranging from 0 to 6 kGy. The limit of detection appears to be approximately 1 kGy. The method was found to be useful for the identification of gamma-irradiated foods such as shrimp, frog legs, pork, beef, and poultry. Results of the method evaluation studies of these food matrices as well as factors affecting hydrocarbon production and determination will be presented.  相似文献   
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