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961.
阐述变压器油气体色谱分析与变压器内部故障之间的内在联系,通过色谱分析监测变压器的运行状况,并介绍变压器油气体色谱超标在线脱气处理方法。 相似文献
962.
辉光放电等离子体处理有机废水研究进展 总被引:1,自引:1,他引:1
辉光放电是一种环境友好的、新兴的电化学高级氧化技术,等离子体是由电极与其周围的电解液产生直流辉光来维持。本文综述了辉光放电等离子体在生物难降解有机废水处理方面的实验装置、特点及机理,介绍了辉光放电等离子体技术的国内外研究现状,探讨了该技术在有机废水处理中存在的问题及其应用前景。 相似文献
963.
β-环糊精是由7个D-吡喃葡萄糖单元通过α-1,4-糖苷键键连成环的超分子主体分子,“内疏水、外亲水”的独特结构赋予了其优异的分子识别能力;氧化石墨烯类材料凭借其优良特性成为近几年的研究热点。由β-环糊精和氧化石墨烯构筑的超分子杂化体在兼具二者特有性能的基础上又有新功能的引入。本文综述了β-环糊精-氧化石墨烯超分子杂化体的构筑方式,按二者间的连接方式,分别为共价键和非共价键两种连接方式,其中通过共价键连接是目前最主要的构筑方式;此外对β-环糊精-氧化石墨烯超分子杂化体的特征和表征进行了简述。同时对β-环糊精-氧化石墨烯超分子杂化体在水污染处理、电化学检测、药物控释和催化等领域的应用进展进行了综述。最后对该超分子杂化体在构筑和应用上的发展趋势进行了展望。 相似文献
964.
高档水基油墨粘度影响因素的研究 总被引:1,自引:0,他引:1
为获得高固低粘的油墨配方体系,通过油墨的分散实验,探讨了分散树脂和乳液及其助剂对水基油墨体系粘度的影响规律,润湿分散剂对水基油墨粘度的影响,胺化剂对水基油墨粘度的影响机理。研究表明,乳液聚合物具有高固低粘特性,拼混使用不同的聚合物可获得理想粘度和应用性能;润湿分散剂能改变体系的表面张力和润湿性能,从而降低水基油墨体系的粘度;拼混使用不同的胺化剂可以获得粘度稳定的水基油墨体系。 相似文献
965.
966.
967.
The surface compositions of a series of polystyrene‐b‐polydimethylsiloxane (PS‐b‐PDMS) and polystyrene‐g‐polydimethylsiloxane (PS‐g‐PDMS) copolymers were investigated using ATR‐FTIR and XPS technique. The results showed that enrichment of PDMS soft segments occurred on the surface of the block copolymers as well as on that of graft copolymers. And the magnitude order of the enrichment was as follows: PS‐b‐PDMS > PS‐g‐PDMS, which was attributed to the facilitating of the movement of the PDMS segments in PS‐b‐PDMS copolymer. Meanwhile, the solvent type and the contact medium had influence on the accumulation of PDMS on the surfaces. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci, 2006 相似文献
968.
Keiichi Okajima 《Electrochimica acta》2005,50(11):2227-2231
Modified activated carbon fibers (ACFs) were used as the electrodes of an electric double-layer capacitor and showed an enhanced capacitance effect after a RF-plasma treatment. The capacitance and the surface functional groups of the ACFs were studied. For the plasma-treated ACFs having a specific surface area of 1500 m2 g−1, the capacitance increased by 28% compared to the untreated sample and the highest electric capacitance value of 142 F g−1 was achieved with an oxygen feed concentration of 10 vol.%. The Brunauer-Emmett-Teller (BET) surface area was 2103 m2 g−1, which was 34% higher than that of the untreated sample. The pore volume was similarly increased to 483.1 cm3 g−1 STP, and from the pore distribution plot, quantities of mesopores of 10 nm or less and micropores also increased. However, in order to enhance the capacitance, the quinone functional group had a significant influence in addition to the BET surface area. The correlation between the capacitance and the number of quinone functional groups was confirmed because quinone is an electron acceptor. 相似文献
969.
Raman spectra of virgin and damaged graphite edge planes 总被引:1,自引:0,他引:1
First-order Raman spectra of virgin and ion irradiated highly oriented pyrolytic graphite were performed along the basal and edge planes. Ion irradiation was performed in the low fluence regime (≈ 1012–1013 ions cm−2) using a 400 keV Ar+ beam in order to a introduce controlled amount of defects in the structure. Virgin edge Raman spectra reveal the presence of a 1351 cm−1 structure (D*) shifted 10 cm−1 away from the disorder induced D-line found upon irradiating or grinding the graphite surface.The 1351 cm−1 D* structure is then considered as the feature coming from the rupture of the D6h4 space group symmetry. A comparison between D* and the classical 1360 cm−1 D-line is discussed in terms of induced disorder. 相似文献
970.
Chien-Chung Chen Chia-Fu Chen I-Hsuan Lee Chien-Liang Lin 《Diamond and Related Materials》2005,14(11-12):1897
Graphitic nanoflakes were fabricated on the carbon nanotubes templates for increasing the surface area utilizing bias assisted microwave plasma enhanced chemical vapor deposition (MWPECVD). The analysis of morphologies and structures were achieved by means of scanning electron microscopy and transmission electron microscopy. The surface area of graphitic nanoflakes, carbon nanotubes (CNTs) and graphitic nanoflakes/CNTs were 57.44 m2/g, 90.31 m2/g and 130.96 m2/g from BET measurement, respectively. The cyclic voltammetry was used to calculate the active area of platinum catalysts in 1 M sulfuric acid from hydrogen adsorption peak. An enhancement of activity could be observed from the calculation of CV results. This may be attributed to the small particle size and high dispersion of platinum particles coated on graphitic nanoflakes/CNTs. These high surface area materials could be used as catalysts supports or electrode for fuel cell applications. 相似文献