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1.
Kerogen is an important organic matter fraction widely spread in soils and sediments. It plays a major role in the sorption and sequestration of hydrophobic organic contaminants (HOCs) such as trichlorobenzene (TCB). It is known that kerogen is geochemically heterogeneous due to the differences in source materials and diagenesis history. We hypothesized that kerogen derived from different source materials and diagenetic history exhibits different sorption properties for TCB. We employed two different kerogen materials (coals) as the original materials and two series of kerogen for a given series with an identical source material but different alteration history were yielded through thermal treatment at temperature ranging from 200 to 500℃. The original and treated materials were characterized for their physicochemical properties. Sorption experiments were conducted with batch reactor systems using 1, 3, 5-TCB as the HOCs sorbates and the original and treated materials as the sorbents.  相似文献   

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The Saf’yanovka copper massive sulfide deposit is situated 10 km northeast from the town of Rezh, on the eastern slope of the Central Urals. The ore-hosting plagiorhyolite-dacitic sequence consists of tephrites and tuffites with interlayers of dark gray siliceous-carboniferous pelites and psephytes from 0.1 to 1.5 m thick. The shells of the Parathurammina tamarae L. Petrovae, 1981 foraminifer were identified in one of the lightened interlayers in the siliceous-carboniferous sequence. The samples for study were taken from the southern part of the orebody in the open-pit between prospecting lines 2 and 3, horizons 170 and 157. The inner part of the shell is composed of quartz and apatite, and the wall, by apatite with rare calcite grains. One shell contains a tacking disk allowing us to refer these foraminifers to the attached benthos typical of the shallow marine basin (sublitoral). In the Urals, the Parathurammina tamarae L. Petrovae, 1981 foraminifer is known in limestones from the Eifel-Givetian (Langurskii and Vysotinskii Horizons); the siliceous-carboniferous rocks from the ore-hosting sequence from the Saf’yanovka deposit has the same age.  相似文献   

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The Gurupi Belt (together with the São Luís cratonic fragment), in north-northeastern Brazil, has been described in previous studies that used extensive field geology, structural analysis, airborne geophysics, zircon U–Pb dating, and whole-rock Sm–Nd isotope and geochemical data as a polyphase orogenic belt, with the Rhyacian being the main period of crust formation. This was related to a 2240 Ma to 2140 Ma accretionary processes that produced juvenile crust, which has subsequently been reworked during a collisional event at 2100 ± 20 Ma, with little evidence of Archean crust. In this study, we use Lu–Hf isotopic data in zircon from granitoids (including gneiss) of variable magmatic series, and amphibolite to improve the knowledge of this scenario, and investigate additional evidence of recycling of Archean basement. Pre-collisional high Ba-Sr and ferroan granitoids and amphibolite formed in island arc (2180–2145 Ma), show only zircons with suprachondritic εHf values (ca. +1 to +8) indicating the large predominance of juvenile magmas. Only 10% of the data show slightly negative εHf values (0 to ?4), which have been observed in granodiorite-gneiss formed in continental arc (2170–2140 Ma), and in strongly peraluminous collisional granites (2125–2070 Ma), indicating the rework of older Paleoproterozoic to Archean components (HfTDM = 2.11–3.69 Ga). A two-component mixing model using both Hf and published Nd isotope data are in line with this interpretation and indicate more than 90% of juvenile material, and less influence of Archean materials. Comparing with other Rhyacian terranes that are interpreted to have been close to Gurupi in a pre-Columbia configuration (ca. 2.0 Ga), our results differ from those of SE-Guiana Shield, which show strong influence of Archean protoliths, and are very similar to those of the central-eastern portion of the Baoulé-Mossi Domain of the West African Craton, which has also been formed largely by juvenile magmas in an accretionary-collisional orogen.  相似文献   

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There occurred rifting on Hainan Island in the Late Palaeozoic. Bimodal volcanic rocks composed ofbasalt and rhyolite developed in the Carboniferous. Widespread in the Late Palaeozoic formations are severallayers of fluvial intermontane conglomerates whose distribution is controlled by rift faults. The Late Palaeozoicdeposits dominaled by clastic rocks are, for a major part, of marine facies and of continental facies in the lowerand upper parts. Lithological and lithochemical studies indicate that the detrital rocks were formed in atectonic setting of continental rifting. The evolution of the rifting terminated at the stage of transition form anintra continental rift to an intercontinental one and the rift basin was a bay opening westward to the sea.  相似文献   

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This paper proposes a scheme for the definition of the Lower Triassic Induan-Olenekian boundary(IOB) based on investigation of sections in Chaohu, Anhui Province, China as well as data accunulated from other studies elsewhere. The conodont Neospathodus waageni is suggested as the index fossil of the boundary. According to the FAD of N.waageni, the IOB is at the base of bed 25-2 of the West Pingdingshan Section in Chaohu,42.19 m above the Permian-Triassic boundary, and it is slightly higher than the base of the Flemingites-Euflemingites Ammonoid Zone at the section.  相似文献   

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《中国地球化学学报》2006,25(B08):I0002-I0002
Preface The International Symposium on Environmental Geochemistry, first held in London, Great Britain in 1985, has become a premier international forum for the presentation and discussion of advances in scientific understanding of environmental geochemistry. The 7^th International Symposium on Environmental Geochemistry is being held in Beijing, China. The symposium is sponsored by the State Key Laboratory of Environmental Geochemistry, Institute of Geochemistry, Chinese Academy of Sciences and the Chinese Society for Mineralogy, Petrology and Geochemistry.  相似文献   

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1 Introduction Because clay minerals have the characteristics ofadsorption, ion exchange capability and expandingcapacity, they are highly capable of adsorbing allkinds of pollutants in waters, thus making soilspossess self-purification functions. Clay m…  相似文献   

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Dr.HuangJing 《《幕》》2004,27(4):296-297
The 3^rd International Conference on Continental Earthquakes, Mechanism, Prediction, Emergency Management & Insurance (the 3^rd ICCE) was held on July 9-14, 2004 in Beijing, China. The ICCE has been held every decade since it was launched over twenty years ago. The first ICCE, with the title ““““International Symposium on Continental Seismicity and Earthquake Prediction““““(ISCSEP), had international sponsorship and was supported by e.g., UNESCO and hosted by the Seismological Society of China (SSC)in Beijing in 1982. In 1992 in response to the initiatives from the UN‘s International Decade for Natural Disaster Reduction (IDNDR),  相似文献   

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On the basis of researches over several years on biostratigraphy of Changhsingian at Meishan Section D in Changxing County, the abundant materials were accumulated. This paper studies the escostratigraphy and establishes 7 community zones (CZ), in ascending order, Sinoplatysomus-Gernitzina-Clarkina subcarinata, Tapashanites-Nodosaria-Clarkina subcarinata,Crurithyris-Geinitzina-Clarkina subcarinata,Glomospira-Clarkina changxingensis, Colaniella-Clarkina changxingensis,Rotodiscoceras-Palaeofusulina-Hindeodus typicalis,Clarkina meishanensis-Hypophiceras.The habitat type (HT) is diffent from upper shallow sea to the lower part of the lower shallow sea.  相似文献   

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Please refer to the attachment(s) for more details.  相似文献   

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The Gandise massif in Tibet, China, is one of the most important copper-multimetal metallogenic belt of Tibet region( Hou, et al,2001 ; Qu, et al, 2001 ;  相似文献   

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Adsorption of dissolved copper and phosphate by natural and peroxide-treated marine sediments was compared. A three-fold increase in copper adsorption and a six-fold increase in phosphate adsorption was caused by the peroxide treatment. Indigenous organic matter evidently interferes with adsorption.Clay minerals coated with heptadecanoic acid adsorbed somewhat less copper, phosphate, and hexadecane than uncoated clays, but slightly more nonadecanoic acid and anthracene.  相似文献   

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This work consists in estimating the role of climatic conditions in the degradation of two French limestones, tuffeau and Richemont stone, used in the construction and the restoration of the Castle of Chambord, the largest castle in the Loire Valley, France. Meteorological data, air temperature, air relative humidity and rainfall were statistically analysed in combination with stone data from thermal–humidity sensors inserted into the walls. The climatic conditions of the surrounding area were described to assess their role in enhancing the degradation of the stones through three weathering processes: thermal stress, condensation and freezing–thawing. The damage risks due to the weathering processes were taken into account not only through the bulk effects on the stone surfaces, but also their effects were extended to investigate the damage that occurs within the porous structure of the stone. Field observations showed that the main patterns of degradation affecting the stones of the castle are biological colonization and stone detachment in the form of stone spalling and exfoliation. The results of the analysis show that there is no risk of damage to the stones due to thermal stress. Moreover, the two stones experience similar overall trends against freezing–thawing processes. Finally, this study clearly highlights the important role of condensation in the degradation of the stones of the castle.  相似文献   

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