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Distribution of Carbon and Oxygen Isotopes in theSequence Stratigraphic Framework of the Middle andUpper Proterozoic in the Ming Tombs Area, Beijing

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Acta Geologica Sinica(English Edition) 1998年第2期72卷 207-216页

作者： li rufeng University of Petroleum Shuiku Road Changping Beijing 102200

Abstract: This paper discusses the distribution pattern and geological significance of the carbon and oxygen isotopes (δ13C and δ18O) in the depositional sequences of Gaoyuzhuangian, Yangzhuangian and Wumishanian ages of the established Middle and Upper Proterozoic sequence stratigraphic framework in the Ming Tombs area lying in western Yanshan Mountain of Beijing. Besides, sketchy determination of δ13C and δ18O was also performed for other formations and members. The analytical results show the following: under the condition of clear-water carbonate sediments, δ13C and δ18O, featuring smaller variation of δ13C but larger variation of δ18O, can well delineate the relative change of sea level, which reflects the difference of primary sedimentary settings; in the presence of terrigenous substances, δ13C values vary greatly while δ18O slightly; the carbon and oxygen isotopes show marked changes at sequence boundaries. Besides, particular patterns can be found in regard to the distribution of carbon and oxygen isotopes within the sequences.

关键词： Ming Tombs in the western Yanshan Mountains of Beijing Middle and Upper Proterozoic sequence stratigraphy carbon and oxygen isotopes

Multiphase redistribution differences of polycyclic aromatic hydrocarbons （PAHs） between two successive sediment suspensions

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Frontiers of Environmental Science & Engineering 2016年第2期10卷 381-389页

作者： rufeng li Chenghong FENG Dongxin WANG Baohua li Zhenyao SHEN The Key Laboratory of Water and Sediment Sciences (Ministry of Education) School of Environment Beijing Normal University Beijing 100875 China

Successive sediment suspensions often happen in estuary, yet little research has probed into the difference in the release behaviors of organic compounds among different suspensions. This study took polycyclic aromatic hydrocarbons （PAHs） as typical organic contaminants and investigated the release behaviors between two successive suspensions with a particle entrainment simulator （PES）. Results showed that successive sediment suspensions lowered the concentration of dissolved PAHs in the overlying water via facilitating the re-adsorption of dissolved PAHs onto the suspended particles. Fast-release and slow-release periods of PAHs were successively observed in the both suspensions. The concentration changes of dissolved PAHs in the second suspension were generally similar with but hysteretic to those in the first suspension. More vigorous desorption and re-absorp- tion of PAHs were induced in the second suspension. Successive sediment suspensions obviously decreased the concentrations of mineral composition and organic matters in the overlying water, which significantly affects multi- phase distribution of PAHs.

关键词： sediment suspension PAHs multiphase dis-tribution distribution coefficients

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减重手术对炎症因子影响的研究进展

广州医药 2024年第5期55卷 463-471,477页

作者：谢娟李汝峰陈婧李珉珉暨南大学附属第一医院临床检验中心广东广州510630 暨南大学附属第一医院减重中心广东广州510630

肥胖是一种以慢性低度炎症为特征的进展性疾病,与多种代谢性疾病的发生、发展密切相关。脂肪组织作为一种内分泌和免疫器官,可分泌多种生物活性物质及炎症因子,参与肥胖患者体内的代谢过程。减重手术是治疗病态性肥胖及相关代谢性疾病... 详细信息

肥胖是一种以慢性低度炎症为特征的进展性疾病,与多种代谢性疾病的发生、发展密切相关。脂肪组织作为一种内分泌和免疫器官,可分泌多种生物活性物质及炎症因子,参与肥胖患者体内的代谢过程。减重手术是治疗病态性肥胖及相关代谢性疾病的有效方法之一,能够调节机体内的炎症反应、有效改善代谢状态。但减重手术对于炎症因子的作用如何,目前国内外的文献证据仍有争议。本文将系统阐述肥胖与代谢性炎症的关系以及减重手术对炎症因子的影响,旨在为肥胖代谢外科的诊疗过程提供参考。

关键词：减重手术炎症因子肥胖脂肪组织巨噬细胞

维普期刊数据库博看期刊

Main Structural Styles and Deformation Mechanisms in the Northern Sichuan Basin,Southern China

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Acta Geologica Sinica(English Edition) 2008年第3期82卷 543-553页

作者： TANG liangjie GUO Tonglou JIN Wenzheng YU Yixin li rufeng State Key Laboratory of Petroleum Resource and Prospecting Beijing 102249 China Basin and Reservoir Research Center China University of Petroleum Beijing 102249 China Key Laboratory for Hydrocarbon Accumulation Mechanism Ministry of Education Beijing 102249 China Southern Exploration and Development Division Company SINOPEC Chengdu 610041 Sichuan China

The Triassic Jialingjiang Formation and Leikoupo Formation are characterized by thick salt layers. Three tectono-stratigraphic sequences can be identified according to detachment layers of Lower-Middle Triassic salt beds in the northern Sichuan Basin, i.e. the sub-salt sequence composed of Sinian to the Lower Triassic Feixianguan Formation, the salt sequence of the Lower Triassic Jialingjiang Formation and Mid-Triassic Leikoupou Formation, and the supra-salt sequence composed of continental clastics of the Upper-Triassic Xujiahe Formation, Jurassic and Cretaceous. A series of specific structural styles, such as intensively deformed belt of basement-involved imbricated thrust belt, basement-involved and salt-detached superimposed deformed belt, buried salt-related detached belt, duplex, piling triangle zone and pop-up, developed in the northern Sichuan Basin. The relatively thin salt beds, associated with the structural deformation of the northern Sichuan Basin, might act as a large decollement layer. The deformation mechanisms in the northern Sichuan Basin included regional compression and shortening, plastic flow and detachment, tectonic upwelling and erosion, gravitational sliding and spreading. The source rocks in the northern Sichuan Basin are strata underlying the salt layer, such as the Cambrian, Silurian and Permian. The structural deformation related to the Triassic salt controlled the styles of traps for hydrocarbon. The formation and development of hydrocarbon traps in the northern Sichuan Basin might have a bearing upon the Lower-Middle Triassic salt sequences which were favorable to the hydrocarbon accumulation and preservation. The salt layers in the Lower-Middle Triassic formed the main cap rocks and are favorable for the accumulation and preservation of hydrocarbon.

关键词： structural style deformation mechanism detachment layer salt-related strucrure hydrocarbon accumulation northern Sichuan Basin

Cycle-Sequences,Carbon Isotope Features and Glacio-Eustasy of the Triticites Zone in Southern Guizhou

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Acta Geologica Sinica(English Edition) 1997年第2期71卷 217-226页

作者： li rufeng liu Benpei and Zhao Chenglin University of Petroleum, Beijing China University of Geosciences, Beijing University of Petroleum, Beijing University of Petroleum Beijing China University of Geosciences Beijing [?]li rufeng Born in 1962 got his doctor's degree in 1995 at China University of Geosciences (Beijing). He is now undertaking postdoctoral research work of carbonate sequence stratigraphy and petroleum geology in Petroleum University (Beijing).

In light of the principle of sequence stratigraphy, detailed analysis of depositionalsequences and systematical carbon isotope measurements were done for the Triticites zone ofthe typical Late Carboniferous section in the Dushan area of southern Guizhou. Two sequencesand seventeen parasequences, which can be correlated with the two sequences and seventeensubsequences in the North American Midcontinent, are distinguished in the Gzhelian, whichprovides convincing evidence of the global synchroneity of the depositional records. The inter-nal relations between carbon isotope evolution and eustasy were studied and the evolutionarycharacteristics of carbon isotopes in depositional sequences have been summarized.

关键词： Upper Carboniferous carbonate sequence stratigraphy eustasy Triticites zone carbon isotope

AN EVIDENCE OF CARBON ISOTOPE TO THE DETERMINATION OF THE CARBONIFEROUS/PERMIAN BOUNDARY

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Scientia Geologica Sinica 1997年第2期 40-44页

作者： li rufeng and Zhou Jinsong(University of Petroleum, Beijing 102200)

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铁路局工程设计管理信息系统研究与应用

中国铁路 2010年第11期 45-47页

作者：李儒峰西安铁路局总工程师室

以铁路局工程设计管理为背景,对铁路局工程设计管理信息系统进行研究,提出管理信息系统的总体目标、研究思路和研究方法。以"工程设计管理为主线"制定系统总体架构,以基本建设项目设计管理为例,对系统的实现和功能进行说明。

关键词：铁路局工程设计管理信息系统研究应用

Observation and Research on the Twisting Characteristics of Flare Loop System

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天文研究与技术 1999年第S1期 438-441页

作者： li rufeng, Bi Shaolan, Dun Jinping (Yunnan Observatory, The Chinese Academy of Sciences, Kunming 650011, China)$$$$

We analyze the evolution of Hβ monochromatic images and Hβ velocity fields of the flare loops system on June 4, 1991. It is the first time to demonstrate directly the dynamic process of the energy storage, transport... 详细信息

关键词： flare loop system twisting energy storage

Fastness and Homogeneous Character of Coating Film on Big Telescope

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天文研究与技术 1999年第S1期 127-129页

作者： Qin Songnian, li rufeng, Gao Cai (Yunnan Observatory, The Chinese Academy of Sciences, Kunming 650011, China)

The paper reports the consideration for fastness and homogeneous character of coating film on large telescope. After coating film, we obtain that the optical homogeneous character of whole mirror is in 1/20 λ, and reflective rate is about 92%. We found that the thin film doesn’t tick to offset paper, and the film is still well after two years.

关键词： Fastness and Homogeneous Character of Coating