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哈士蟆油中脂肪酸的GC、GC-MS分析 总被引:5,自引:0,他引:5
用气相色谱(GC)与气相色谱-质谱(GC-MS)联用技术对哈士蟆油中的脂肪酸组成进行了定性与定量分析,共鉴定出10种脂肪酸并用气相色谱法作了定量,对所得的结果进行了讨论。 相似文献
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人参挥发油的提取和分析 总被引:7,自引:0,他引:7
应用GC-MS-DS联机分析人参挥发油是当前较好的方法,但人参挥发油的提取方法和GC-MS条件的选择明显影响人参挥发油这一复杂天然混合物的分离和鉴定。本工作严格控制提取条件,提高了挥发油收率,达0.95%;选择最佳GC-MS条件,鉴定出76种化合物,该法稳定重现性好。 相似文献
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用超临界流体萃取和固相萃取分析水中酚类污染物 总被引:3,自引:0,他引:3
使用自制的超临界流体萃取仪,比较了从Chromosorb,Porapark和GDX系列的8种吸附剂上萃取苯酚,邻硝基酚,邻氯酚,对氯酚,对二甲酚,2,4-二氯酚和2,4,6-三氯酚的回收率。并用萃取回收率比较高的GDX-301富集1L酸性水样中10^-7g/mL级的以上各酚,然后用超临界CO2脱附,回收率从32.5%到92.9%,同时还对超临界CO2脱附GDX-301上各酚的操作条件进行了优化,并 相似文献
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气相色谱/质谱法鉴定甲基异丁基酮产品中的杂质组分 总被引:1,自引:0,他引:1
采用GC/MS联用技术分离出甲基异丁基酮产品中6个杂质峰。将标准图谱库,质量色谱图等手段结合起来鉴定出7种杂质,并用标样,双柱对部分GC/MS的结果进行了证实,为产品质量控制提供依据。 相似文献
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生物降解ε—己内酯/d,l—丙交酯共聚物的合成与表征 总被引:6,自引:0,他引:6
采用一种新型的稀土配位化合物Y(CF3COO)3/Al(i-Bu)3为催化剂,制备了不同组成的ε-己内酯/d,l-丙交酯共聚物,并用GPC、NMR和DSC表征了共聚物的结构.结果表明通过改变初始投料中两种单体的比例,可以调节共聚酯的化学结构,而共聚物的形态则受结构影响很大. 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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电子鼻结合人工智能对呼出气进行检测、分析和识别已成为非侵入性医疗检测领域的研究热点。然而,目前已报道的气体传感材料尚不能同时满足高灵敏度、高选择性和稳定的室温检测,阻碍了气体传感器在医疗健康领域的应用及发展,寻找合适的传感材料具有重要的意义和挑战。新型二维层状纳米材料MXenes具有种类多、比表面积大、导电性能强、表面含有丰富的官能团以及能带宽度可调等优异性能,是高灵敏、低能耗气体传感器的明星候选材料。本综述针对MXenes基材料的特殊结构,总结梳理了MXenes基材料在气体传感中的最新研究成果,聚焦于MXenes材料的气体传感机理和改性方法,对MXenes材料用于气体传感依然存在的问题和挑战进行深入探讨。 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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A novel correlation for estimation of hydrate forming condition of natural gases 总被引:1,自引:0,他引:1 下载免费PDF全文
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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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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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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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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