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991.
This study assesses the displacement of coalbed methane by CO2 migration along a fault into the coal seam in the Yaojie coalfield. Coal and gas samples were collected continuously at various distances in NO.2 coal seam from F19 fault. Vitrinite reflectance, maceral, and pore distributions and proximate analysis of fourteen coal samples were performed. Gas components, concentrations, carbon isotopes of 28 gas samples were determined. We examined the coal–gas trace characteristics of coalbed methane displaced away from the fault by CO2 injection after geological ages. From east to west, away from the F19 fault, the CO2 concentration decreased, whereas the CH4 concentration increased gradually. The δ13C values for CO2 varied between ?9.94‰ and 1.12‰, suggesting a metamorphic origin. A wider range of values (from ?9.94‰ to 20‰) was associated with the mixing of microbial carbon dioxide, isotopic fractionation during CO2 migration through the microporous structures of coals, and/or carbon isotope fractionation during gas–water exchange and dissolution of CO2. Away from the F19 fault, the volumes of micropores, mesopores and macropores decrease gradually. The Dubinin–Radushkevich (DR) micropore volume decreased from 0.0059 to 0.0037 cm3 g‐1, and the mesopore and macropore volumes decreased from 0.066 to 0.026 cm3 g‐1. The CO2 injection can mobilize aromatic hydrocarbons and mineral matter from coal matrix, resulting in the decrease in the absorption peak intensity for coal samples after supercritical CO2 treatment, which indicates that chemical reactions occur between coal and CO2, not only physical adsorption. 相似文献
992.
J. Zhu Y. Zhang T. Wang C. H. Zhao J. C. Yu M. D. Glascock C. S. Wang 《Archaeometry》2014,56(4):562-572
The traditional thermal expansion method using a dilatometer fails to accurately determine the original firing temperatures of low‐fired ancient pottery. For this reason, we have developed an improved method of determining firing temperatures for low‐fired pottery. This paper explains the theory of the improved method and presents the reasonably satisfactory results obtained on ancient pottery from the Donghulin site (c. 10 000 bp ). The method and the results are very important for the study of ancient pottery culture and clay moulds used for bronze casting. 相似文献
993.
目前看来,西游学界主要从中原文化中探寻《西游记》故事的演变过程,少有学者从民族的视角去审视藏文化与《西游记》的关系。殊不知,西游学界忽略了一个重要的历史事实,在《西游记》故事获得重大发展的元代及明代前中期,正是藏文化,特别是藏传佛教大量传入中原时期。从《西游记》《金瓶梅》等明代小说中出现的藏传佛教元素,足可证明,西藏文化直接或间接地影响了元明时期内地的文学创作。近年来,随着西游学研究视野的拓宽,以及大量藏学文献的汉译,为深入研究西藏文化与《西游记》关系,提供了更为便利的条件。 相似文献
994.
Wang Shuo Cheng PengPhoto 《中国西藏(英文版)》2014,(1):F0002-F0002
<正>The 9th award ceremony of Dorampa Geshi Degree,the advanced degree in the Tibetan Buddhism,was held in the High-level Tibetan Buddhism College of China,Beiji... 相似文献
995.
Feng Chen Yujiang Yuan Wenshou Wei Shulong Yu Huaming Shang Tongwen Zhang Ruibo Zhang Huiqin Wang Li Qin 《Geochronometria》2014,41(3):234-244
We developed a Faxon fir (Abies faxoniana) tree-ring width chronology at the timberline in the western Qinling Mountains, China. Herein February–July mean temperature was reconstructed for Zhouqu in the western Qinling Mountains back to AD 1650 based on the standard chronology. The climate/tree-growth model accounts for 43.5% of the instrumental temperature variance during the period 1972–2006. Spatial correlation analyses with the gridded temperature data shows that the temperature reconstruction captures regional climatic variations over central and southeast China, and strong teleconnections with the nearby High Asia. There is a good agreement with cold and warm periods previously estimated from tree-rings in Nepal, India and southwest China. The temperature re-construction indicates that there was pronounced cooling in Zhouqu during the Maunder Minimum (late 1600s to early 1700s). The cold period (1813–1827) of the temperature reconstruction coincide with the volcanic eruptions. Significant spectral peaks are found at 56.9, 22.3, 11.4, 2.9, 2.8, 2.6, 2.2 and 2.0 years. The spatial correlation patterns between our temperature reconstruction and SSTs of the Atlantic and Pacific Oceans suggest a connection between regional temperature variations and the atmospheric circulations. It is thus revealed that the chronology has enough potential to reconstruct the climatic variability further into the past. 相似文献
996.
电视媒体既要服从市场规律,又要服从政府意志,政府控制与市场动力之间的复杂关系成为中国电视业的显著特征。当今中国社会发展变革的新环境,使中国电视媒体不可避免地具有了意识形态宣传机构和市场盈利机构的"双重身份"。如何正确处理两者的关系,是中国电视业未来发展的关键。 相似文献
997.
998.
为了充分反映精神文明建设情况,体现社会变迁中人们思想道德的重大变化,广东在第二轮省志中设《专记·精神文明建设》。《精神文明建设》(送复审稿)虽然全面系统记述了广东省精神文明创建活动,但是仍存在记述范围不广、程度不深以及公文化倾向等问题。修志过度依赖行政手段,修志队伍不稳定,资料来源单一,传播渠道过度狭窄,缺乏社会反馈等修志路径是产生上述问题的主要原因。为了打破这种依赖,提高省志编修质量,最终实现修志一用志一修志的良性循环,可以采用如下改进措施:完善修志工作体制,打破对行政手段的过度依赖;重视地情资料搜集、考订,打破对档案资料的过度依赖;培养修志专家,打破临时拼凑修志班子的现象;加强地情研究,打破千志一面的现象;提高传播能力,打破“皇帝女儿不愁嫁”的现象。 相似文献
999.
随着20世纪70年代中期以来神木石峁遗址调查资料的相继刊布[1],人们逐渐开始重新检视海外各学术机构和博物馆收藏的中国古玉,将许多重要藏品特别是风格独特的墨绿色牙璋类器物的产地追溯到了石峁遗址。据称大英博物 相似文献
1000.