共查询到17条相似文献，搜索用时 281 毫秒
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膨胀石墨对甲基橙废水吸附脱色的研究 总被引：5，自引：0，他引：5
本研究以利用酸洗技术制备的膨胀石墨为吸附剂,以浓度为100 mg/L的甲基橙溶液为模拟废水进行吸附脱色。试验主要从膨胀石墨的膨胀容积、膨胀石墨的用量以及脱色时间三个影响因素对膨胀石墨的吸附脱色性能进行讨论,通过多因素正交试验确定室温条件下的最佳脱色工艺条件为:25 mL模拟废水中加入0.25 g膨胀容积为350 mL/g的膨胀石墨,匀速振荡1.5 h。试验脱色时间短,且脱色效果显著,脱色率为99.99%。 相似文献
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[目的]探究多孔材料对黑曲霉生长的影响。[方法]以膨胀石墨和硅藻土为添加剂,将其加入PDA培养基中,观察其对黑曲霉的作用。[结果]培养24 h后,加入膨胀石墨的培养基中黑曲霉菌落直径大于对照。加入硅藻土的培养基中黑曲霉菌落直径与对照差异不显著。培养48 h后,加入膨胀石墨的培养基中黑曲霉菌落直径大于硅藻土,且2种培养基中的黑曲霉菌落直径均大于对照。[结论]培养24 h后,膨胀石墨对黑曲霉有促菌作用,而硅藻土无明显作用;培养48 h后,膨胀石墨对黑曲霉促菌作用优于硅藻土;72 h后,膨胀石墨及硅藻土对黑曲霉促菌作用差异不显著。 相似文献
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以浓硝酸为插入剂制备无硫可膨胀石墨 总被引：10，自引：0，他引：10
用浓硝酸和天然鳞片石墨反应制备无硫可膨胀石墨 ,最佳反应条件是 :石墨与浓硝酸的质量比为 1∶2 ,反应温度为 30℃ ,反应时间为 10min ,可膨胀石墨的膨胀容积为 30 0mL·g-1,不含硫。 相似文献
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为研制氨吸附制冷用活性炭一膨胀石墨的混合吸附剂,选用椰壳活性炭和可膨胀石墨,初步分析了氨在膨胀石墨添加比率为50％的混合吸附剂上的吸附平衡．吸附剂试样首先经由77K液氮在其上吸附数据的结构表征,然后应用根据容积法原理建立的吸附平衡测试装置,在温度293．15～303．15K、压力0—1MPa,测试了氨在试样上的吸附平衡数据,并通过等量吸附线标绘和Dubinin—Astakhov方程的模型分析,研究了氨在混合吸附剂上的吸附平衡．结果表明,添加膨胀石墨减小了混合吸附剂的比表面积和微孔容积,Dubinin—Astakhov方程在平衡压力较高区域的预测精度可达到4％,氨在混合吸附剂上的等量吸附热为16．94～27．78kJ／mol．添加膨胀石墨必须兼顾混合吸附剂的吸附容量和传热传质性能． 相似文献
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制备低硫可膨胀石墨的新工艺 总被引：5，自引：0，他引：5
用硫酸(98％)、硝酸(65％)和草酸的混合液与天然鳞片石墨反应制备低硫可膨胀石墨。最佳反应条件是：石墨、硫酸(98％)、硝酸(65％)、草酸的重量比为1：2．3：1．7：0．05，反应时间45min，反应温度为25℃，可膨胀石墨的含硫量为1．63％时，膨胀容积为250mL/g，其终端产品柔性石墨的含硫量为780mg/kg。 相似文献
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以复合插入剂制备低温可膨胀石墨 总被引：2，自引：0，他引：2
天然鳞片石墨为基质,以氯酸与冰醋酸作复合插入剂,以高锰酸钾为氧化剂,制备低温可膨胀石墨。其最佳工艺条件为天然石墨:硝酸:高锰酸钾:氯酸钾:冰醋酸=1∶0.6∶0.05∶0.2∶0.5(质量比),在室温下反应50min,再进行脱色、水洗、抽滤、烘干得产品,产品的起始膨胀温度为124℃,在600℃膨胀容积可达245 mL/g。 相似文献
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本文研究了隐晶质石墨原矿、中间石墨及高碳石墨，获得了不同阶段隐晶质的结构参数。隐晶质石墨结构同样在化学、物理作用下会发生变化、经过在似鳞片石墨的层间化合物。隐晶质石墨与酸、碱作用，其微晶中插入了某些基团，而杂质并未在衍射谱线上显示出来。本文对隐晶质原矿提纯也有参考意义。 相似文献
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通过式外光谱仪的分析测定，确定石墨残存化合物存在朱少官能团，这些官能团对石墨的结构有影响，对石墨的性能也有直接影响，通过电阻率的测定，发现了性能的重大变化，本文对其影响做了详细分析。 相似文献
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Kovalenko I Zdyrko B Magasinski A Hertzberg B Milicev Z Burtovyy R Luzinov I Yushin G 《Science (New York, N.Y.)》2011,334(6052):75-79
The identification of similarities in the material requirements for applications of interest and those of living organisms provides opportunities to use renewable natural resources to develop better materials and design better devices. In our work, we harness this strategy to build high-capacity silicon (Si) nanopowder-based lithium (Li)-ion batteries with improved performance characteristics. Si offers more than one order of magnitude higher capacity than graphite, but it exhibits dramatic volume changes during electrochemical alloying and de-alloying with Li, which typically leads to rapid anode degradation. We show that mixing Si nanopowder with alginate, a natural polysaccharide extracted from brown algae, yields a stable battery anode possessing reversible capacity eight times higher than that of the state-of-the-art graphitic anodes. 相似文献
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We report the synthesis of tubular graphite cones using a chemical vapor deposition method. The cones have nanometer-sized tips, micrometer-sized roots, and hollow interiors with a diameter ranging from about 2 to several tens of nanometers. The cones are composed of cylindrical graphite sheets; a continuous shortening of the graphite layers from the interior to the exterior makes them cone-shaped. All of the tubular graphite cones have a faceted morphology. The constituent graphite sheets have identical chiralities of a zigzag type across the entire diameter, imparting structural control to tubular-based carbon structures. The tubular graphite cones have potential for use as tips for scanning probe microscopy, but with greater rigidity and easier mounting than currently used carbon nanotubes. 相似文献
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Mao WL Mao HK Eng PJ Trainor TP Newville M Kao CC Heinz DL Shu J Meng Y Hemley RJ 《Science (New York, N.Y.)》2003,302(5644):425-427
Compressed under ambient temperature, graphite undergoes a transition at approximately 17 gigapascals. The near K-edge spectroscopy of carbon using synchrotron x-ray inelastic scattering reveals that half of the pi-bonds between graphite layers convert to sigma-bonds, whereas the other half remain as pi-bonds in the high-pressure form. The x-ray diffraction pattern of the high-pressure form is consistent with a distorted graphite structure in which bridging carbon atoms between graphite layers pair and form sigma-bonds, whereas the nonbridging carbon atoms remain unpaired with pi-bonds. The high-pressure form is superhard, capable of indenting cubic-diamond single crystals. 相似文献
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本文报道了应用Ｘ－射线衍射分析及其它一些实验手段，研究钼在石墨炉内石墨探针表面上的原子化机理。结果表明：钼的原子化源于它的碳化物的热离解。 相似文献
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Cai W Piner RD Stadermann FJ Park S Shaibat MA Ishii Y Yang D Velamakanni A An SJ Stoller M An J Chen D Ruoff RS 《Science (New York, N.Y.)》2008,321(5897):1815-1817
The detailed chemical structure of graphite oxide (GO), a layered material prepared from graphite almost 150 years ago and a precursor to chemically modified graphenes, has not been previously resolved because of the pseudo-random chemical functionalization of each layer, as well as variations in exact composition. Carbon-13 (13C) solid-state nuclear magnetic resonance (SSNMR) spectra of GO for natural abundance 13C have poor signal-to-noise ratios. Approximately 100% 13C-labeled graphite was made and converted to 13C-labeled GO, and 13C SSNMR was used to reveal details of the chemical bonding network, including the chemical groups and their connections. Carbon-13-labeled graphite can be used to prepare chemically modified graphenes for 13C SSNMR analysis with enhanced sensitivity and for fundamental studies of 13C-labeled graphite and graphene. 相似文献