原子吸收光谱法测定裂解汽油中铅

报道了用火焰原子吸收光谱法测定裂解汽油中铅的方法。用碘 二甲苯溶液对汽油进行氧化处理,用稀硝酸进行萃取,萃取后浓缩液用原子吸收光谱法进行测定。铅含量在0～7.0μg·ml-1范围内符合比耳定律。对汽油样品进行分析时,相对标准偏差小于3.95%,对样品进行加标回收试验,回收率为97.7%～101.7%,方法的精密度和准确度良好。     

Highly tilted antiferroelectric (R) enantiomers useful for the formulation of eutectic mixtures

ABSTRACT

Novel chiral three-ring (R) enantiomers were synthesised using optically active (R)-(?)-2-octanol. Properties, such as the sequence of phases, the transition temperatures and enthalpies, were tested by a polarising optical microscope and differential scanning calorimeter. An antiferroelectric smectic phase (SmC_A*) with a direct transition from the antiferroelectric to the isotropic phase (SmC_A*-Iso) was observed for three esters with an achiral C₃F₇CH₂O(CH₂)₃O– terminal chain. Bi- and multicomponent mixtures with a broad temperature range of the antiferroelectric phase and good electro-optical properties were formulated. Helical pitch of pure esters and mixtures was measured by spectrophotometry method.     

Simultaneous determination of cobalt,copper, iron and vanadium in crude petroleum oils by HPLC

Summary A method has been developed for the simultaneous formation and solvent extraction of cobalt (II), copper (II), iron (II) and vanadium (IV) complexes of bis (acetylpivalylmethane)ethylenediamine (H₂APM₂en) in methyl isobutyl ketone. The complexes are eluted from a reversed phase HPLC column with a mixture of methanol:water:acetonitrile and detection was at 260 nm. The method has been applied to the simultaneous determination of cobalt, copper, iron and vanadium in crude petroleum oils at the ng level.     

Mesoscopic structure and properties of liquid crystalline mesophase pitch and its transformation into carbon fiber

The history and present state of the art in the chemistry of mesophase pitch, which is an important precursor for carbon fiber and other high-performance industrial carbons, are reviewed relative to their structural properties. The structural concepts in both microscopic and macroscopic views are summarized in terms of the sp(2) carbon hexagonal plane as a basic unit common to graphitic materials, its planar stacking in clusters, and cluster assembly into microdomains and domains, the latter of which reflect the isochromatic unit of optical anisotropy. Such a series of structural units is described in a semiquantitative manner corresponding to the same units of graphitic materials, although the size and stacking height of the hexagonal planes (graphitic sheets) are very different. Mesophase pitch is a liquid crystal material whose basic structural concepts are maintained in the temperature range of 250 to 350 degrees C. The melt flow and thermal properties are related to its micro- and mesoscopic structure. The structure of mesophase-pitch-based carbon fiber of high tensile strength, modulus, and thermal conductivity has been formed through spinning, and has inherited the same structural concepts of mesophase pitch. Stabilization settles the structure in successive heat treatments up to 3000 degrees C. Carbonization and graphitization enable growth of the hexagonal planes and their stacking into units of graphite. Such growth is governed and controlled by the alignment of micro- and mesoscopic structures in the mesophase pitch, which define the derived carbon materials as nanostructural materials. Their properties are controlled by the nanoscopic units that are expected to behave as nanomaterials when appropriately isolated or handled.     

Origin of immature sulfur-rich oil in Jianghan oil field

Chemical structure of immature sulfur-rich kerogen and composition of immature sulfur-rich crude oil in Jianghun oil field have been studied. In molecular level, crude oil differs from thermolysed and chemolysed products of kerogen but does resemble the bitumen in immature sulfur-rich source rock. Therefore, immature sulfur-rich oil may be derived from the expelling of bitumen rather than from thermal cracking of kerogen.     

超大比表面石油沥青基碳纤维微电极研究

作者研制了一种以石油沥青基碳纤维为电极材料的微电极,基于此种材料的特殊性能,经氧化处理后可获得较一般微电极为大的比表面积,因而其电流响应亦较一般微电极为大。且由于其表面在一定条件下可生成大量的碳氧基团,故其电极电位会随溶液ｐＨ值而线性变化,以至该电极亦可用作测量ｐＨ值的微电极。     

SPORES AND POLLEN IN CRUDE OILS AND PETROLEUM SOURCE OF TARIM BASIN

One hundred and forty-seven species of spores and pollen referred to 77 genera found in the crudeoil samples taken from four petroliferous provinces of the Tarim Basin of Xinjiang Provincehave been studied in this paper. By means of these spore and pollen fossils, the geological ages anddistribution of the petroleum source rocks of the basin are judged. Also, the principles and methodsto judge the petroleum source of a petroleum province by spore/pollen and other microfossils in crudeoils are explained.     

双烯合成反应与气相色谱法联合测定油品中共轭二烯烃含量的研究 Ⅱ.短毛细管柱气相色谱法

在填充柱气相色谱法的基础上，使用１２ｍ×０．２２ｍｍｉ．ｄ．的ＳＥ－３０短毛细管柱（ＷＣＯＴ），分析了乙烯生产副产物——未加氢裂解汽油（５５℃～２２０℃馏分）中共轭二烯烃的含量，分析一次需２２ｍｉｎ，内标物正十六烷得到了很好的分离。     

石油焦与煤混合燃料热重分析研究

石油焦与煤混合燃烧是高效处理石油焦的有效方法，作者对选用的石油焦和煤不同配比的混合燃料进行了热重分析研究。使用常压高温热天平研究、分析了各配比混合燃料的热解特性和燃烧特性。并根据化学动力学方法计算了各过程的化学动力学参数，即活化能E和频率因子A0。结果表明，各混合燃料热解起始温度大致相同，随煤焦比减小，挥发分析出速率变缓，最大释放速度所对应的温度升高，最终失重率减小，挥发分释放特性指数减小；随煤焦比增大，混合燃料着火温度和燃尽温度逐渐降低，最大燃烧速率所对应的温度降低，燃烧特性指数增大；随煤焦比减小，活化能和频率因子增大。