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1.
Francisco M. Baena-Moreno Mónica Rodríguez-Galán Fernando Vega Luis F. Vilches Benito Navarrete 《International Journal of Green Energy》2019,16(5):401-412
Biomethane production through biogas upgrading is a promising renewable energy for some industries which could be part of the equilibrium needed with fossil fuels consumption to achieve a sustainable society. This paper presents a comprehensive list of biogas upgrading technologies focused on carbon dioxide removal as well as recent advances reported by researcher with wide expertise in this topic. Additionally, an extensive costs–performance comparison among the technologies studied is discussed. Among the different alternatives, chemical scrubbing stood out to achieve high biomethane purities while cryogenic technologies proved to be effective against methane losses. Regarding the different costs, water scrubbing and membrane separation seem to be the most affordable techniques. 相似文献
2.
为了探究重金属对肺表面活性物质(PS)膜的影响,利用Langmuir–Wilhelmy膜天平,研究了不同种类和浓度的重金属离子与PS单层膜的相互作用.发现Cr3+、Cu2+、Hg2+、Pb2+、Cd2+、Ni2+6种重金属离子均使PS单层的π-A等温线G-LE相变阶段外扩,而Fe3+可诱导单层缩合.随后,选取Cd2+,Cu2+,Hg2+,Fe3+4种离子进一步探究了重金属浓度对PS单层膜表面活性的影响规律,进行了可压缩模量分析,并结合红外光谱(FTIR)和原子力显微镜(AFM)探究其作用机理,发现Cu2+,Fe3+和Hg2+均会以浓度依赖的方式与PS单层的极性头部发生络合作用,形成复合物,改变膜的稳定性;而Cd2+的影响明显弱于其他3种金属离子,但也能使得PS单层有序性增强. 相似文献
3.
对螯合树脂在线富集,火焰原子吸收光度法进行了条件试验。试验证实方法对Cu、Pb、Zn、Cd4个元素检出浓度可达μg/L级,校准曲线性、样品重现性及准确度可满足测定要求。 相似文献
4.
采用火焰原子吸收分光光度法测定鱼内脏及河流底泥中的铜。鱼内脏经组织捣碎机捣成匀浆后,加硝酸消解;底泥则经氢氟酸和高氯酸消化。该方法具有灵敏度高,精密度和回收率较好等特点。 相似文献
5.
Goyal SK 《Environmental monitoring and assessment》2003,89(3):305-314
Sodium arsenite (modified Jacobs and Hochheiser method; hereafter referred as SA), the most widely used manual monitoring method for determination of nitrogen dioxide (NO2) in ambient air, particularly in developing countries has been evaluated and compared with US EPA recommended equivalent method of TGS-ANSA (hereafter referred as ANSA). NO2 concentrations generated from laboratory test atmosphere were analyzed by these two methods and were compared statistically. Laboratory evaluations showed that SA method has high sensitivity to different sampling conditions, which normally vary during actual field monitoring. Hence, correction factors for absorption efficiency were estimated for SA and ANSA methods. Absorption efficiency of NO2 in SA method was found to be much lower (64%) as against the reported value of 82% at the method recommended sampling conditions, whereas for ANSA method, it was found 1.0 as against the reported value of 0.93. After applying derived correction factors, both the methods produced almost similar concentration values of NO2. 相似文献
6.
7.
研究了表面活性剂(乳化剂OP)存在下,铁、邻菲罗啉、曙红的显色反应.该离子缔合物的最大吸收波长为545 nm,摩尔吸光系数为9.4×104 L·mol-1·cm-1,铁含量在0-0.4 mg/L内符合比耳定律.以自来水为基体进行铁的回收实验,回收率在99%以上. 相似文献
8.
9.
对铜的 3条谱线 (2 49.2 nm、2 61 .4nm,3 2 4.8nm ) ,铅的 2条谱线 (2 83 .3 nm、2 1 7.0 1 nm )以及锌的 2条谱线(3 0 7.6nm、2 1 3 .9nm ) ,共 7条谱线的灵敏度、检测限、线性范围进行了归纳性总结 ,并对多种共存元素可能存在的干扰情况进行了研究 ,认为利用元素不同分析谱线的分析灵敏度差异 ,根据被测元素在样品消解液中含量 ,选择合适的谱线进行分析 ,既降低工作强度 ,又能获得满意结果 相似文献
10.
Toral MI Beattie A Santibañez C Richter P 《Environmental monitoring and assessment》2002,76(3):263-274
A first derivative spectrophotometric method has been developedfor the determination of parathion and p-nitrophenol in vegetabletissues. Ethanol was used as solvent for extracting the compoundsfrom the tissues and subsequently the samples were evaluated against a vegetable tissue blank, directly by derivative spectrophotometry. The simultaneous determination of these compounds can be carried out using the zero-crossing approach for parathion at 253.0 nm and for p-nitrophenol at 273.1 nm. In the samples each analyte was determined in the presence of one another in the ranges between 4.9 to 3883.5 g g-1 forparathion and 4.9 to 3285.3 g g-1 for p-nitrophenol.The detection limits (3) were found to be 1.5 and 1.4 g g-1 for parathion and p-nitrophenol, respectively. The relative standard deviations were in all instances less than1.8%. The proposed method was applied to the determination ofthe analytes in spiked leafs of corn. The results show a goodrecovery and they are in agreement with those obtained bypolarography. 相似文献