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61.
One‐dimensional MoO3 nanofibers doped with Ce (MoO3 : CeO2) are synthesized by a method combining a sol‐gel process and an electrospinning technique. The resulting MoO3 : CeO2 is characterized by X‐ray diffraction (XRD), X‐ray photoelectron spectroscopy (XPS), Fourier transform infrared (FT‐IR) spectroscopy, and scanning electron microscopy (SEM). The catalytic degradation of rhodamine B and safranin‐T with MoO3 : CeO2 nanofiber catalyst is investigated in a continuous flowing mode using air (O2) as an oxidant. The results show that rhodamine B and safranin‐T are degraded effectively and the removal efficiencies are 98.3%, and 98.5%, respectively. In addition, the organic dyes are totally mineralized to simple inorganic species such as CO3–, Cl– and NO3–. 相似文献
62.
James C. Hower Jennifer M.K. O'Keefe Michael A. Watt Timothy J. Pratt Cortland F. Eble J.D. Stucker Allison R. Richardson Irena J. Kostova 《International Journal of Coal Geology》2009,80(2):135-143
Macrinite is a, generally, rare inertinite maceral, often incorporating remnants and fragments of other macerals, including vitrinite, liptinite, and other inertinite. The associated inertinites include multiple forms of funginite. Funginite is also commonly found in association with vitrinite of slightly elevated reflectance and with degraded varieties of vitrinite. Together with the highly degraded macrinite, the latter two associations are here inferred to be part of a continuum of fungal and microbial degradation of peat. In any case, the origin of some macrinite is potentially distinct from that of inertinite generated by fire. 相似文献
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64.
The chemical degradation characteristics of reinforced concrete reefs, which had been fully immersed in Tongyeong waters of South Korea for 18–25 years, were studied. In order to investigate the marine environmental impact on the concrete reefs, environmental factors, for example pH, have been observed between 1997 and 2002. Then, four reinforced concrete reefs recovered from different sites in Tongyeong waters were nondestructively tested. Finally, those test results were analyzed to determine the chemical deterioration. Based on the test results, it is shown that the reinforced concrete reefs have sound chemical properties and their originally estimated service life is secure enough for a further service period in water depths of 28–32 m. A concrete cover depth of 40 mm is recommended for the design of reinforced concrete reefs to achieve safety in marine environments and special events occurring during installation and construction. 相似文献
65.
Advanced characterization of marine dissolved organic matter by combining reversed-phase liquid chromatography and FT-ICR-MS 总被引:1,自引:0,他引:1
Boris P. Koch Kai-Uwe Ludwichowski Gerhard Kattner Thorsten Dittmar Matthias Witt 《Marine Chemistry》2008,111(3-4):233-241
Marine dissolved organic matter (DOM) was separated by reversed-phase (RP) liquid chromatography method and analyzed with fluorescence/absorption detection and Fourier transform ion cyclotron mass spectrometry (FT-ICR-MS). The three key characteristics of the RP method are: (a) The C18-RP column chosen provides enhanced separation when the aqueous phase is 100% buffer-free water, and it does not degrade over time; (b) the water eluent adjusted to pH 7 significantly improves the resolution of water soluble compounds; (c) the initial flow maintained at low levels improves the separation of polar compounds. In samples, containing “fresh” DOM, specific peaks were detected, which were absent in “old” DOM samples. The combination with size exclusion chromatography (SEC) also demonstrated the relation between polarity and molecular size of DOM. FT-ICR-MS was applied to evaluate the quality of separation on a molecular scale demonstrating that physico-chemical characteristics of DOM can be related to molecular formulas. Sample extracts were separated into 4 preparative fractions, and a large suite of the identified molecular formulas only occurred in specific fractions. This is an important basis for the application of further analytical techniques in order to perform a more target-oriented analysis aiming at the determination of source and process biomarkers for DOM. 相似文献
66.
青藏高原未来50a地表气温可能增高2.2~2.6℃,以高温、高含冰量冻土为特色的多年冻土区将延续退化的趋势,因此青藏铁路多年冻土区路基工程建设和维护必须采用冷却路基的原则,变传统消极被动保温为积极主动降温以维护路基热稳定性。为降低或消除工程建设及气候变暖造成的路基下多年冻土融化,目前青藏铁路实施的调控对流、调控传导和调控辐射的工程措施,基本上达到了保持或促进路基下伏多年冻土的效果。数值模拟结果表明路基工程建设和补强措施基本可以应对气候转暖的不良影响,但部分措施还需要进一步优化或组合。 相似文献
67.
ONTHEPREDICTIONOFTRANSIENTBEDLEVELSDUETOAGGRADATIONANDDEGRADATIONINCLUDINGARMOURINGA.B.PALANIAPPAN1,R.J.GARDE2andP.N.GODBOLE3... 相似文献
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69.
用GDX 102树脂从海洋浮游植物三角褐指藻(Phaeodactylum tricornutum)的分解产物和代谢产物中分离提取腐植类物质(DHS,EHS)及乙醇可溶物(DES,EES),用~1H-NMR,IR和UV光谱进行结构分析,并同海水中腐植质(HS)和乙醇可溶物(ES)做了比较。结果表明,DHS,EHS和HS都以高支链烷烃、碳水化合物和氨基酸结构为主要组分,另有少量芳烃和杂环化合物。它们的化学结构很相似,说明DHS和EHS是海水腐植质的重要来源。 相似文献
70.
José M. Echavarren 《社会与自然资源》2017,30(2):145-159
This article analyzes the effect of environmental degradation, the affluence hypothesis, and postmaterialist theory to assess the environmental concern of individuals in 51 countries. The hypotheses are tested using a multilevel analysis that employs an unprecedented number of objective indicators of environmental degradation, using the World Values Survey 6th wave (2010–2014). The results support the degradation hypotheses, where the importance of water scarcity in a country and national biodiversity are the major variables that explain individual environmental concern among all the indicators of environmental degradation. The affluence hypothesis is rejected and the postmaterialist theory is supported only at the individual level. 相似文献