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Progress of High Performance Proton Exchange Membranes for Fuel Cells

Qian GAO, Dan CHENG, Manhua DUAN, Wei XIAO

Abstract （426）

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Proton exchange membrane fuel cell (PEMFC) is characterized by high efficiency and environmental protection, and has great potential for development in solving energy and environmental problems.Proton exchange membrane (PEM) is one of the key components of PEMFC, which affects the performance and cost of the cell. Existing commercial Nafion type PEMs have a problems in balance of high cost, conductivity and mechanical properties. PEMs with low cost and excellent performance can improve the performance and commercialization of fuel cells. To address the compatibility problem of conductivity and mechanical properties of PEMs, researchers have designed a variety of enhanced PEM materials in terms of membrane constituent materials and microcosmic nano structures. Here, the requirements of PEMFC for PEM are briefly introduced, and the preparation methods of novel PEM based on doped nanomaterials, composite resin cross?linking and porous skeleton are mainly analyzed. The characteristics of membrane properties before and after modification are compared, and the problems in the preparation process of PEM are briefly analyzed, and the future research directions of PEM are further prospected.

2024, 37 (4): 66-75. DOI: 10.12422/j.issn.1006-396X.2024.04.009

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Determination of Original Oil Saturation for Chang 8 Layer in Northeastern Zhiluo Oilfield

Wang Zhongyuan, Wang Guicheng, Chang Weili, Wei Xiaodi

Abstract （308）

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Chang 8 layer in northeastern Zhiluo oilfield of Ordos basin is a structural lithologic reservoir controlled chiefly by lithology with many oil water layers. There are many oil water layers in this region. Aiming at this characteristic, on the basis of the methods of pressure coring, mercury injection and log data interpretation, the data of relative permeability analysis is used to to interpret and revise the original oil saturation in the area. The four methods are used to calculate the original oil saturation in Chang 8 layer of northeastern Zhiluo oilfield and the advantages and disadvantages of each method are analysized. The reasonable original oil saturation in Chang 8 layer of this area is determined, and the accuracy of calculation of reserves is improved. The method of relative permeability analysis data is the best method to calculate the original oil saturation in this area, eventually the original oil saturation value is 45.6%.

2016, 29 (2): 37-43. DOI: 10.3969/j.issn.1006-396X.2016.02.008

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The Rhizosphere Effect in Phytoremediation of the Petroleum Polluted Soil

WANG Jing， ZHANG Zhong-zhi， SU You-ming， WEI Xiao-fang， HE Feng， HE Wei

Abstract （288）

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The experiment studied on the rhizosphere effect in phytoremediation of the petroleum polluted soil by three kinds of grasses which were Pannicum， Eleusine indica(L.) Gaerth and Tall Fescue. After a period of 150 d ,this pot experiment show that the three kinds of plants rhizosphere accelerated the degradation of petroleum in different degrees.The results show that the plant roots improved the soil moisture which increased 5% compared with unplanted control soil .The dehydrogenas activity is 0.61～1.20 times higher.The number of microorganisms in the rhizosphere increased three orders of magnitude.The abduction of plant rhizosphere environment and the coercion of petroleum changed the distribution and activity of microorganisms.The petroleum degradation rates in the rhizosphere are 22.1%～30.3% higher than in the unplanted control soil.The effect of rhizosphere degeneration changed the component of petroleum obviously.It strengthened the degeneration degree of normal hydrocarbons that had low and moderate carbon.The plant rhizosphere environment is favorable to degenerate the high-carbon hydrocarbons into the low-carbon hydrocarbons.At the same time the peak area ratios of Pr/nC ₁₇,Ph/nC ^₁₈ and Pr/Ph have been enhanced 0.99,2.69 and 1.25 respectively.It accelerated the isomerization of normal hydrocarbons.

2008, 21 (2): 36-40.

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Construction of a Genetic Engineering Strain That Can Produce Extracellular Polyssacharidesin Higher Temperature for MEOR

YI Wen-jing, ZHANG Zhong-zhi*,SUN Shan-shan, WEI Xiao-fang, LUO Yi-jing

Abstract （286）

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A strain screened from the waste water of an oilfield can produce insoluble extracellular polysaccharide used in selective plugging which is instrumental in microbially enhanced oil recovery. However this strain is sensitive to high temperature and produces little extracellular polyssacharides above 40 ℃. Therefore pET-ecoRRF, pET-tteRRF and corresponding control plasmids were transformed into the strain. The new strain can grow in 45 ℃, and western-blot indicates that the RRF genes have been expressed noticeably in the transgene strains. It has been showed that the transgene strains are able to bear higher temperature, and the sustainable temperature is higher five to eight degrees than the original strain. Because Enterobacter sp. is related to Escherichia coli, the expression of RRF is better than the gene of Thermus thermophilus in the strain of JD. At last it is successful to get a genetic engineering microbe which can endure the temperature as high as 45 ℃ and produce extracellular polysaccharides.

2007, 20 (4): 25-27.

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Ex Site-Bioremediation of Petroleum-Contaminated Soil With Exogenous Microbe

WEI Xiao-fang, ZHANG Zhong-zhi﹡, GUO Shao-hui, JI De-kun, LUO Yi-jing, SU You-ming

Abstract （331）

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Experiment was undertaken for ex site-bioremediation of oil-contaminated soil which comes from Dagang oilfield, whether the exogenous microbes accelerate the rate of the bioremediation or not is studied and the impact factors on the biodegradation of the petroleum-contaminated soil were investigated too. The collected soil were divided into two groups then mixed, and the total petroleum hydrocarbon(TPH) was 8 416, 16 385 mg/kg respectively. The TPH of the soil was monitored during the treatment and the influence factors such as indigenous consortium, bio-stimulating, different exogenous microbe, bulk agent (sawdust), the varied initial TPH of the soil were investigated. The components changes of the bio-treated oil and the untreated oil were analyzed by GC-MS. The experiment was lasted for 300 d. When the water content of the soil is given, the exogenous microorganism can speed up the biodegradation of the petroleum greatly, and the reduction ratio of TPH reached to 79% with the combination of the exogenous microbe and bulk agent. The results of GC-MS show that the alkane can be better metabolized by microorganisms when their molecular weight are less than C ₂₈ and the microbes can biodegradate the polycyclic aromatic hydrocarbon efficiently.

2007, 20 (2): 1-4.