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Experimental study on the interaction between peat,lignite and germanium-bearing solution at low temperature

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Science China Earth Sciences 2005年第9期48卷 1411-1417页

作者： QI Huawen1,2. HU Ruizhong1 & QI Liang1 1. Key Laboratory of Ore Deposit Geochemistry, Chinese academy of Sciences, Guiyang 550002. China 2. Department of Earth Science, nanjing University, nanjing 2.0093. China Key Laboratory of Ore Deposit Geochemistry Chinese Academy of Sciences Guiyang China Department of Earth Science Nanjing University Nanjing Chin

The interaction between peat, lignite and germanium(Ge)-bearing solution with an initial Ge concentration of 5 mg/L was studied at 2.―100℃ and at pH 2.96―12.08. The results show that the apparent transfer ratios of peat and lignite for Ge in the solution were positively correlated with temperature in acid environment (initial pH=2.96), and the ratios (up to 86.5%) of lignite were obviously higher than those (up to 58.5%) of peat, but the organic transfer ratios of lignite were lower than those of peat. The activation energy values for interaction between peat, lignite and Ge-bearing solution are 3..96 and 15.67 kJmol?1, respectively. The strong acid (initial pH=2.96) and the strong alkaline (initial pH=12.08) environment contribute to the transfer of Ge in the solution. At 43.) conduces to the transfer of Ge into lignite. The interaction between peat, lignite and Ge-bearing solution are mainly attributable for the complexation of Ge with organic substrate. The experimental results from this study provide direct experimental evidence for the hydrothermal sedimentary genesis of abnormal enrichment of Ge in coal.

关键词： low temperature, peat, lignite, Ge4+, complexation.

Narrow line Seyfert 1 galaxies: where are the broad line regions?

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Science China(Physics,Mechanics & Astronomy) 2010年第12期53卷 2307-2311,2339-2343页

作者： MAO WeiMing 1,2.3., HU Chen 2., WANG JianMin 2., BIAN WeiHao 4 , ZHANG Shu 2.& ZHAO Gang 1 1 Key Laboratory of Optical Astronomy, National Astronomical Observatories, Chinese academy of Sciences, Beijing 100012. China 2.Key Laboratory for Particle Astrophysics, Institute of High Energy Physics, Chinese academy of Sciences, Beijing 100049, China 3.Graduate University of the Chinese academy of Sciences, Beijing 100049, China 4 Department of Physics, nanjing Normal University, nanjing 2.0011, China Key Laboratory of Optical Astronomy National Astronomical Observatories Chinese Academy of Sciences Beijing China Key Laboratory for Particle Astrophysics Institute of High Energy Physics Chinese Academy of Sciences Beijing China Graduate University of the Chinese academy of Sciences Beijing China Department of Physics Nanjing Normal University Nanjing China

A sample consisting of 2.1 narrow line Seyfert 1 galaxies (NLS1s) with high quality spectra from the Sloan Digital Sky Survey (SDSS) is selected to explore where broad line regions are in these objects. We find that the Hβ profile can be fitted well by three (narrow, intermediate and broad) Gaussian components, and the FWHM ratios of the broad to the intermediate components hold a constant of 3.0 roughly for the entire sample. If the broad components originate from the region scaled by the well-determined Hβ reverberation mapping relation, we find that the intermediate components originate from the inner edge of the torus, which is scaled by dust K-band reverberation. We find that the IC and the BC are strongly linked dynamically, but the relation of their covering factors is much more relaxed, implying that both regions are clumpy.

关键词： black hole physics galaxies: evolution quasars: general

Whole fossil plants of Ephedra and their implications on the morphology,ecology and evolution of Ephedraceae (Gnetales)

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Chinese Science Bulletin 2010年第15期55卷 1511-1519页

作者： WANG Xin 1,2.& ZHENG ShaoLin 3.1 nanjing Institute of Geology and Palaeontology,Chinese academy of Sciences,nanjing 2.0008,China 2.Fairy Lake Botanical Garden,Shenzhen 518004,China 3.Shenyang Institute of Geology and Mineral Resources,Shenyang 11003.,China nanjing Institute of Geology and Palaeontology Chinese Academy of Sciences Nanjing China Fairy Lake Botanical Garden Shenzhen China Shenyang Institute of Geology and Mineral Resources Shenyang China

Although there are many reports of fossil Ephedraceae,whole plant fossil record remains *** to a lack of trust on partially preserved fossil materials,scholars working on molecular clock proposed a recent origin of Ephedra and cast doubt on the earlier origin time of *** better the understanding on this interesting group,here we report whole plants of Ephedra hongtaoi ***.(Ephedraceae,Gnetales) from the Yixian Formation (Early Cretaceous) in western Liaoning,*** whole plants of Ephedra demonstrate clearly the characters of Ephedra,including shrubby growth habit,decussate branching pattern,and terminal ovuliferous unit with micropylar *** whole-plant preservation of the fossils provides more convincing fossil evidence of Early Cretaceous Ephedra,helps to resolve the controversy over the origin time of Ephedra,and sheds light on the whole plant morphology,growth habit,ecology and evolution of Ephedraceae.

关键词：化石植物生态学麻黄形态学进化材料保存早白垩世生长习性

Detection of water in petroleum inclusions and its implications

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Science Bulletin 2006年第12期51卷 1501-1507页

作者： CAO Jian1, YAO Suping1, HU Wenxuan1, ZHANG Yijie2. WANG Xulong3. ZHANG Yueqian3.& TANG Yong3.1. State Key Laboratory for Mineral Deposit Research, Department of Earth Sciences, nanjing University, nanjing 2.0093. China 2. Research Institute of Exploration and Development, PetroChina, Bei- jing 100083. China 3. Research Institute of Exploration and Development, Xinjiang Oilfield Company, PetroChina, Karamay 83.000, China State Key Laboratory for Mineral Deposit Research Department of Earth Sciences Nanjing University Nanjing China Research Institute of Exploration and Development PetroChina Beijing China Research Institute of Exploration and Development Xinjiang Oilfield Company PetroChina Karamay China

FTIR spectra of inclusions sampled from fault-zone reservoirs of the northwestern Junggar Basin show that water, with different abundances, does exist in petroleum inclusions. It is thus implied that petroleum inclusions can seldom form without water. Different inclusions hosted in one single grain, and formed in one oil charging phase, have a largely varied ratio of water to oil and slightly changed CH3.CH2.ratio. This likely provides evidence for fault-related episodic migration and accumulation of hydrocarbons.

关键词： water in petroleum inclusions forming mechanism of inclusions episodic migration and accumulation of hydrocarbons FTIR microspectroscopy Junggar Basin.

Schmeissneria:An angiosperm from the Early Jurassic

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Journal of Systematics and Evolution 2010年第5期48卷 326-335页

作者： 1,2.in WANG 1(nanjing Institute of Geology and Palaeontology,Chinese academy of Sciences,nanjing 2.0008,China) 2.Fairylake Botanical Garden,Shenzhen 518004,China) (nanjing Institute of Geology and Palaeontology Chinese Academy of Sciences Nanjing 210008 China) (Fairylake Botanical Garden Shenzhen 518004 China)

The origin of angiosperms has been a focus of intensive research for a long *** so-called pre-Cretaceous angiosperms,including Schmeissneria,are usually clouded with *** expel the cloud around the enigmatic Schmeissneria,the syntype and new materials of Schmeissneria collected previously in Germany and recently in China are *** materials include female inflorescences and *** latter are old materials but were under-studied *** microscopy and scanning electron microscope observations indicate that the fruits in these infructescences have in situ seeds enclosed,and that the ovaries are closed be fore *** the plants meet two strict criteria for angiosperms:angiospermy plus *** Schmeissneria in angiosperms will extend the record of angiosperms up to the Early Jurassic,more compatible with many molecular dating conclusions on the age of angiosperms,and demanding a reassessment of the current doctrines on the origin of *** the phylogenetic relationship of Schmeissneria to other angiosperms apparently is still an open question,this study adds to research concerning the origin of angiosperms.

关键词： angiosperm earliest evolution flower fossil Germany Jurassic origin.

A new method to prepare clean cuticular membrane from fossil leaves with thin and fragile cuticles

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Science China Earth Sciences 2011年第2期54卷 223-227页

作者： WANG Li1,2.& LENG Qin1,3.1 State Key Laboratory of Palaeobiology and Stratigraphy,nanjing Institute of Geology and Palaeontology,Chinese academy of Sciences,nanjing 2.0008,China 2.Graduate School of Chinese academy of Sciences,Beijing 100049,China 3.Department of Science and Technology,Bryant University,Smithfield RI 02.17,USA State Key Laboratory of Palaeobiology and Stratigraphy Nanjing Institute of Geology and Palaeontology Chinese Academy of Sciences Nanjing China Graduate School of Chinese academy of Sciences Beijing China Department of Science and Technology Bryant University Smithfield USA

Leaf cuticle analysis has long been a powerful tool for fossil plant identification, systematics, and palaeoclimatological recon- struction. In recent decades the application of stomatal frequency data that are relied on precise calculation of stomata on plant fossil cuticles to reconstruct ancient atmospheric CO2.concentration made the preparation of cuticular membrane with sufficient size a critical technique in palaeoclimatological research. However, for plants with originally thin and fragile cuticles, e.g., most deciduous plants, conventional techniques sometimes fail to obtain cuticular membranes with sufficient size, or sometimes unable to recover any. This has largely hampered the usage of fossil cuticle analysis in palaeobotanical and palaeo- climatological research. Here, we describe a new method using clear nail polish as a medium to ＂strengthen＂ the originally thin and fragile cuticles prior to maceration procedures. We demonstrate the method by using middle Eocene Metasequoia fossils that were notorious for the difficulty of recovering large-sized clean cuticular membranes due to their thin and fragile nature. Metasequoia, with well-documented and widely-distributed fossil records since the Late Cretaceous and with a living repre- sentative, 114. glyptostroboides, as a comparative reference, bas been widely used as a model genus for the study of evolution of plants, palaeoclimatological reconstruction, and plant adaptation to climate changes. But its deciduous habit produces thin cuticles and makes the preparation of clean cuticular membranes a tedious process. The new method successfully allows us to recover its delicate cuticular membranes with sufficient sizes for SEM observation and stomatal frequency analysis.

关键词： fossil leaf cuticle Metasequoia new method thin and fragile cuticle SEM observation stomatal frequency CO2

A general model for estimating actual evaporation from non-saturated surfaces

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Journal of Geographical Sciences 2002年第4期12卷 479-484页

作者： QIU Xinfa1,2. ZENG Yan3. LIU Changming3.1. Dept. of Urban && Resource Science, nanjing University, nanjing 2.0093. China 2. Dept. of Geography, nanjing Institute of Meteorology, nanjing 2.0044, China 3. Inst. of Geographic Sciences and Natural Resources Dept. of Urban & Resource Science Nanjing University Nanjing China Dept. of Geography Nanjing Institute of Meteorology Nanjing China Inst. of Geographic Sciences and Natural Resources Research CAS Beijing China

Based on energy balance equation and mass transfer equation, a general model to estimate actual evaporation from non-saturated surfaces was derived. Making use of two concepts, “relative evaporation” and “relative drying power”, a relationship was established to account for the departure from saturated conditions. Using this model, the actual evaporation (evapotranspiration) can be calculated without the need of potential evaporation estimation. Furthermore, the model requires only a few meteorological parameters that are readily and routinely obtainable at standard weather stations. Based on nearly 3. years data of 43.0}meteorological stations and 512.hydrological stations in China, in combined with GIS, nine typical river basins were selected. Using the data of the selected river basins, the model was tested. The results show that the actual evaporation rate can be estimated with an error of less than 10% in most areas of China, except few years in the Yellow River Basin.

关键词： potential evaporation actual evaporation

Estimation of annual actual evapotranspiration from nonsaturated land surfaces with conventional meteorological data

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Science China Earth Sciences 2004年第3期47卷 239-246页

作者： QIU Xinfa1, ZENG Yan2. MIAO Qilong1 & YU Qiang2.1. Department of Geography, nanjing Institute of Meteorology, nanjing 2.0044, China 2. Institute of Geographic Sciences and Natural Resources Research, Chinese {2. of Sciences, Beijing 100101, China Department of Geography Nanjing Institute of Meteorology Nanjing 210044 China Inst. of Geogr. Sci./Nat. Rsrc. Res. Chinese Academy of Sciences Beijing 100101 China

Views diverge greatly on the relationship between actual evapotranspiration (AE) and potential evapotranspiration (PE). Penman showed that AE is determined in intensity by PE and changes proportionally as a function of PE. In contrast, Bouchet indicated that AE deter-mines PE and varies inversely with PE. Based on nearly 3. years data from 43.0}weather stations and 512.hydrological stations in China, the two different theories, Penman抯 assumption and Bouchet抯 complementary relationship between AE and PE, were tested on nine river basins. With data integration technique, the complementary relationship between AE and PE was dis-played entirely. A general model to estimate the actual evapotranspiration from nonsaturated surfaces by routine meteorological observations has been established on the basis of thorough analysis of the concept of PE. The results show that the calculations are all in error control of <10%, except for a few years over the Yellow River Basin.

关键词： complementary relationship of evapotranspiration, potential evapotranspiration, actual evapotranspiration.

Temporal-spatial variations of euphotic depth of typical lake regions in Lake Taihu and its ecological environmental significance

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Science China Earth Sciences 2006年第4期49卷 431-442页

作者： ZHANG Yunlin1, 2. QIN Boqiang1, HU Weiping1, WANG Sumin1, CHEN Yuwei1 & CHEN Weimin1 1. nanjing Institute of Geography & Limnology, Chinese academy of Sciences, nanjing 2.0008, China 2. Graduate School of the Chinese academy of Sciences, Beijing 10003., China nanjing Institute of Geography & Limnology Chinese Academy of Sciences Nanjing China Graduate School of the Chinese academy of Sciences Beijing China

By using the data of underwater irradiance measured in the different lakeregions of Lake Taihu during 1998—2.04 and total suspended solids (TSS), wind speeds of the total13.stations in typical lake regions during 1993.2.03. this paper analyzes the factors ofinfluencing on PAR (pho-tosynthetically available radiation) attenuation, euphotic depth, andpresents the temporal and spatial variations of euphotic depth of typical lake regions in LakeTaihu, and the spectral distributions of euphotic depth at station 2. The results show that theconcentration of TSS is the most important factor impacting PAR attenuation, followed by chlorophylla; chromophoric dissolved organic matter (CDOM) has little impact on the PAR euphotic depth. During1993.2.03. the mean yearly PAR euphotic depths of the typical lake regions ranged from 1.04 to1.95 m with a mean value of 1.3.±0.2. m. The PAR euphotic depth fell into 3.spatial zone types:Type Ⅰ, the lowest, including the lake center and the inflows of rivers; Type Ⅱ, intermediate,including Meiliang Bay, Wulihu Lake and Gonghu Bay; Type Ⅲ, the greatest, including the East LakeTaihu; corresponding mean depths were approximately 1.1, 1.4, 2.0 m, respectively. The seasonalvariations of euphotic depths were not quite the same in different lake regions. In the lake center,the mean values of PAR euphotic depth in summer and autumn were significantly greater than those inwinter and spring; in the Meiliang Bay, winter means were significantly greater than in the otherthree seasons; in the East Lake Taihu, winter means were significantly less than in the other threeseasons. However, no distinct seasonal change was recorded in the Wulihu Lake, Gonghu Bay and theinflows of rivers. The spectral distributions of euphotic depth present a minimal value at the bluelight wave band of 400 nm, and a peak at the green light wave band of around 580 nm. In 1998 and1999, based on the seasonal many-day continuous measurements, the PAR euphotic depths at station 2.

关键词： lake taihu euphotic depth diffuse attenuation coefficient total suspendedsolid ecological