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为了构建内蒙古扎鲁特地区无烟煤的分子结构模型,采用工业分析、元素分析、核磁共振碳谱、高分辨率透射电镜和X射线光电子能谱等测试方法对该地区无烟煤的分子结构进行研究。结果表明无烟煤分子结构中以芳香碳为主,脂肪碳以短烷基侧链和环烷烃为主。煤分子结构中氧原子主要以酚羟基和醚氧基的形式存在,氮原子主要以吡咯型氮和吡啶型氮的形式存在,硫原子主要的赋存形态是硫醇硫酚。结合由核磁共振碳谱测得的煤结构参数和由高分辨率透射电镜测得的芳香环尺寸和含量,构建了无烟煤大分子平均结构模型。对构建的模型进行了结构优化与能量分析,发现煤分子结构的芳香片层趋于平行排列,非键结势能中的范德华力是保持煤结构稳定的主要因素。本研究为采用分子动力学模拟从分子尺度研究扎鲁特地区无烟煤在石墨化过程中,其芳香碳层的拼叠过程及其反应路径提供了模型基础。 相似文献
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陈儒庆 《大地构造与成矿学》1995,19(4):344-353
角岩化无烟煤首见于湖南省骑田岭花岗岩周围晚二叠世煤层中,它是一种低级热接触变质岩。本文在研究角岩化无烟煤岩石学特征的基础上,详细分析了其岩石化学、微量元素、稀土元素和碳同位素的地球化学特征及其有机物的X射线衍射、红外光谱和喇曼光谱特征。并探讨了角岩化无烟煤发现的地质意义。 相似文献
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The Lackawanna synclinorium of Pennsylvania contains abundant coal that was altered to anthracite rank during the Late Paleozoic Alleghanian orogeny. Why did the coal in the synclinorium undergo anthracitization? Two alternatives have been suggested. (1) The region was buried deeply during and/or after the Alleghanian orogeny and thus became hot in response to Earth's geothermal gradient; and (2) hot fluids migrating from the orogen toward the foreland carried heat into the coal and caused anthracitization. If the second hypothesis is correct, the region should contain evidence that hot fluids passed through the coal. Field observations, illite-crystallinity studies and fluid-inclusion analyses indicate that the coal-bearing Pottsville and Llewellyn Formations, and an underlying detachment fault, called the Pottchunk fault (at or slightly below the base of the Pottsville Formation), acted as a regional aquifer for the migration of hot fluids during the Alleghanian orogeny. The presence of quartz veins and the hydrothermal minerals tosudite and pyrophyllite in strata above the Pottchunk fault, and the apparent absence of an illite-crystallinity burial gradient in the underlying strata, suggest that fluids migrated through large pores in coarse-grained sandstones, through abundant fractures that developed in response to Alleghanian deformation, and along the Pottchunk fault. The quartz veins, tosudite and pyrophyllite mineralization do not occur below the Pottchunk fault (except at one locality), suggesting that fluid flow was greater above the fault, perhaps because fracturing accompanying deformation increased permeability of the fault's hanging wall. Fluid inclusions in the Pottsville and Llewellyn Formations indicate fluids achieved a minimum temperature of 270 °C at a depth of 3.1–8.5 km. Heat-flow calculations constrained by fluid-inclusion data show the heat carried by the migrating fluids through the coal-bearing strata was sufficient to elevate the rock temperature to anthracite-grade conditions (250 °C), assuming that the fluid event lasted about 1 year. Thus, deep burial (6–9 km) of the coal-bearing strata in the Lackawanna synclinorium was not required for anthracitization. Anthracitization was likely the result of stratigraphically controlled hot fluid migration through the coal-bearing strata at shallow depths (≤5 km). 相似文献
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无烟煤泥岩夹矸的岩石矿物学特征及其研究意义 总被引：2，自引：0，他引：2
对山西晋城矿区3号无烟煤层进行了实地观测，采集了一定数量的标本，通过显微镜下鉴定、差热分析、X射线粉晶衍射分析、红外吸收光谱分析等一系列测试手段对无烟煤层中泥岩夹矸的岩石矿物学特征进行了研究，对其主要成分高岭石发生变化的主要原因及影响因素进行了探讨。结果发现，无烟煤层中泥岩夹矸的主要成分高岭石因受不同因素的影响而向不同方向发生转化，主要表现在高岭石向伊利石转化，并有伊利石-蒙脱石(I/S)混层矿物及蒙脱石出现。造成这种煤的变质程度升高而其夹矸成分转化的主要原因可能是区域变质作用及周围介质条件影响所致。 相似文献
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汝箕沟煤中矿物的成因研究及其意义 总被引：1，自引：0，他引：1
本文在较大量和详细的煤岩煤质研究之后，进而用电子探针、扫描电镜及显微镜热台等对宁夏汝箕沟无烟煤中矿物的分成、晶形、微量元素、包裹体温等进行了成因研究。结果表明，汝箕沟煤中的次生矿物及原生矿物的次生变化均与中－低温热液作用有关，这将为该区煤变质成因提供直接证据。 相似文献
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Simultaneous In Situ Analysis of Carbon and Nitrogen Isotope Ratios in Organic Matter by Secondary Ion Mass Spectrometry 
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下载免费PDF全文 Akizumi Ishida Kouki Kitajima Kenneth H. Williford Michael L. Tuite Takeshi Kakegawa John W. Valley 《Geostandards and Geoanalytical Research》2018,42(2):189-203
An in situ measurement method for simultaneous determination of carbon and nitrogen isotope ratios in organic matter was developed by secondary ion mass spectrometry with a spatial resolution of ~ 12 μm. Secondary ion intensities of 12C?2, 12C13C?, 12C14N? and 12C15N? were simultaneously measured by three Faraday cups and one electron multiplier. Ions of 12C2H? were measured to monitor hydride interferences and to correct for mass bias. The analytical precisions of δ13C and δ15N values of a reference material (UWLA‐1 anthracite) were 0.16‰ and 0.56‰, respectively (2s). A negative correlation was observed between the mass bias of carbon and 12C2H?/12C?2 ratios of examined reference materials. In contrast, there was no correlation between mass bias and hydrogen concentration for nitrogen. The δ13CVPDB and δ15NAir values of twenty‐two individual globules of organic matter, found in carbonate rock of the 1878 Ma Gunflint Formation, were determined by the new procedure, ranging from ?33.8‰ to ?33.3‰ and +4.2‰ to 5.8‰, respectively. Means of δ13CVPDB and δ15NAir values, ?33.5 ± 0.25‰ and +5.2 ± 0.81‰, are consistent with reported values from bulk sample analysis within analytical precision. 相似文献
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炼钢增碳剂—一种类石墨的研制 总被引：2，自引：0，他引：2
以优质无烟煤为原料,经选矿提纯,提高煤的碳含量,现经石墨化处理制得炼钢增碳剂。产品主要技术指标：ｗ（Ｃ）≥９０％,ｗ（灰分）〈７％,ｗ（挥发分）〈３％,ｗ（Ｓ）＝０．４３％,ｗ（Ｐ）＝０．０６％,颗粒电阻〈１．０Ω／粒,抗压强度为２１．０ｋｇ／粒。 相似文献
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The results of the study of optical properties of 13 anthracites from different parts of the world are presented in this paper. Measurements of reflectance values were made on non-oriented vitrinite grains for a minimum of 300 points per sample. The reconstruction of Reflectance Indicating Surfaces (RIS) were made by Kilby's method [Kilby, W.E., 1988. Recognition of vitrinite with non-uniaxial negative reflectance characteristics. Int. J. Coal Geol. 9, 267–285; Kilby, W.E., 1991. Vitrinite reflectance measurement — some technique enhancements and relationships. Int. J. Coal Geol. 19, 201–218]. It was found that the use of Kilby's method for strongly anisotropic materials like anthracites did not give unambiguous results. Some improvement in Kilby's method, consisting of the division of the cumulative cross-plot into several elemental components, is suggested. Each elemental cross-plot corresponds to a textural class of anthracite, which is characterized by the values of RIS main axes RMAX(k), RINT(k) and RMIN(k) (k=1,2,…n; n — number of classes). The global texture of anthracite is characterized as a RIS with main axes calculated as the weighted means of
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and
for each class of this anthracite.The division of cumulative Kilby's cross-plot on elemental components makes possible the calculation of new coefficients Ht and H10 characterizing the heterogeneity of the structure and texture of anthracites. The results of our study show that all anthracites have biaxial negative textures, but their heterogeneity varies in a wide range of Ht and H10 coefficients depending upon the individual coal basin. 相似文献
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