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电化学储能器件的性能很大程度上决定于其电极材料。碳材料具有来源广泛、化学稳定性好、易于调控、环境友好等优点,被广泛应用于各类能量存储系统,但仍存在能量密度低、倍率性能差等问题。本文从碳材料孔结构调控、杂原子掺杂、与金属氧化物复合三个角度,综述了构建高性能碳基储能材料的设计合成策略,介绍了其在锂/钠离子二次电池、超级电容器等领域的研究进展,对几种方法策略的优缺点进行了总结,并对未来的研究方向进行了展望。本文对高性能碳基储能电极材料的设计开发具有积极意义。 相似文献
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采用XPS、XRD、FT IR、13C NMR、元素分析等手段分析表征了中低温煤焦油正庚烷沥青质(CT C7沥青质),系统研究了CT C7沥青质表面元素的赋存状态、相对含量以及其晶体结构。结果表明,该沥青质的主要结构为多环稠合芳香烃并富含杂原子,其芳香度(fa)明显大于一般原油沥青质;烷基链间距和芳香片层直径值较小,其芳环上烷基侧链短而少且难以形成堆积结构;表面C主要以sp2和sp3碳的形式存在,二者摩尔分数之和达699%,以C=O和COO-基团存在的C较少。该沥青质表面的杂原子以O原子为主,N和S原子较少,其中含氧官能团主要是酚羟基和醚氧基,摩尔分数达619%。含氮官能团主要以吡啶氮(N 6)和吡咯氮(N 5)为主,二者摩尔分数之和为805%;含硫官能团中,噻吩硫、烷基硫比较多,摩尔分数之和达517%。该C7沥青质表面加氢难度较大的N 6、N 5和噻吩硫的摩尔分数低于石油沥青质,这可能是煤焦油加氢工艺中N、S脱除效率较高的原因之一。 相似文献
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采用水热法在Si O2-Cr2O3-Co O-(TEA)2O-H2O-NH4F体系中((TEA)2O:氧化四乙基铵)合成了具有良好结晶的双杂原子Cr-Co-β沸石,通过XRD,FTIR,UV-Vis,TG-DTG,SEM等技术对试样的结构进行了表征。以H2O2为氧化剂氧化苯乙烯为探针反应,考察了Cr-Co-β沸石的催化活性,研究了溶剂种类、金属配比、H2O2与苯乙烯的摩尔比、催化剂用量、反应时间和反应温度等对反应的影响。实验结果表明,以丙酮为溶剂,以n(Si)∶n(Cr+Co)=20的Cr-Co-β沸石为催化剂,在催化剂用量60 mg、苯乙烯用量17 mmol、H2O2与苯乙烯的摩尔比3、反应温度70℃、反应时间7 h的条件下,苯乙烯转化率为88.4%,苯甲醛选择性为85.3%,环氧苯乙烷选择性为10.7%,苯甲醛收率为75.4%。 相似文献
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A. E. Chemodanov R. R. Akhmadullin V. A. Sudakov S. A. Usmanov R. K. Khayrtdinov 《Petroleum Science and Technology》2018,36(14):1100-1106
The purpose of this study is to detect lateral and vertical gradients of relative concentrations of compounds presented in oil, which allows assessing potential drainage zones in the reservoir during the reservoir production by steam injection. In this research new method for monitoring of steam chamber development in 2D model was created and tested. Methodology: Total hydrocarbon fraction was isolated from core extracts and analyzed by GCMS method (TIC) for detection of various compounds and assessment of lateral and vertical gradients of their concentration in lateral. It was found that the ratio of 4- and 1-methyldibenzothiophenes (MDBT) changes in lateral and in vertical directions. These changes are caused by biodegradation of organic matter. Laboratory research shows that 1-MDBT/4-MDBT ratio in native reservoir rocks is stable under high temperatures and pressure and can be easily measured by GC-MS. This measurement will allow assessment of location and direction of steam chamber propagation. In recent work the authors have developed geochemical model which can be used for assessment of oil flow directions during the development of heavy oil fields by SAGD method. 相似文献
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负离子电喷雾-傅里叶变化离子回旋共振质谱仪(Neg ESI FT-ICR MS)具有超高的分辨率,可用于分析重油中杂原子化合物的组成及分布.运用Neg ESI FT-ICR MS,研究委内瑞拉奥里常渣减黏裂化反应前后杂原子化合物,建立了分子组成的解析方法.结果表明,常渣中O_2类化合物的相对丰度最大,减黏产物中N_1类化合物的相对丰度最大.不同缩合度,质荷比小的O_2类化合物减黏裂化反应后显著增加.委内瑞拉常渣及其减黏产物中相对丰度最强的O_2类化合物均是双环环烷酸.减黏裂化反应使得O2类化合物发生了裂化反应,生成碳数更少、分子质量更小的化合物. 相似文献
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通过在AlPO-n分子筛中掺杂不同的金属或非金属元素制备杂原子AlPO-n分子筛,不仅具有AlPO-n分子筛的规整结构、良好热稳定和水热稳定性,还具有可调控的酸性质、离子交换位点、催化活性中心和择形性,使杂原子AlPO-n分子筛在催化、气体吸附和化学分离等方面展现巨大潜力。综述近年来杂原子AlPO-n分子筛的研究进展,介绍杂原子掺杂的制备方法、模板剂效应和取代性能变化,描述杂原子AlPO-n分子筛的应用前景。 相似文献
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Veronika V. Zlobina Alexey S. Kiryutin Igor A. Nikovskiy Oleg I. Artyushin Vitaly P. Kozinenko Alexander S. Peregudov Alexandra V. Yurkovskaya Valentin V. Novikov 《International journal of molecular sciences》2023,24(1)
Parahydrogen-induced nuclear polarization offers a significant increase in the sensitivity of NMR spectroscopy to create new probes for medical diagnostics by magnetic resonance imaging. As precursors of the biocompatible hyperpolarized probes, unsaturated derivatives of phosphoric acid, propargyl and allyl phosphates, are proposed. The polarization transfer to 1H and 31P nuclei of the products of their hydrogenation by parahydrogen under the ALTADENA and PASADENA conditions, and by the PH-ECHO-INEPT+ pulse sequence of NMR spectroscopy, resulted in a very high signal amplification, which is among the largest for parahydrogen-induced nuclear polarization transfer to the 31P nucleus. 相似文献
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