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Boron isotopic fractionation in laboratory inorganic carbonate precipitation:Evidence for the incorpora-tion of B(OH)_3 into carbonate

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Science China Earth sciences 2008年第12期51卷 1776-1785页

作者： XIAO YingKai1,2, LI HuaLing1,3, LIU WeiGuo4. WANG XiuFang1 & JIANG ShaoYong5 1 Qinghai institute of Salt Lakes, chinese academy of sciences, Xining 810008, China 2 State Key Laboratory of Environmental Geochemistry, institute of Geochemistry, chinese academy of sciences, Guiyang 550002, China 3 {4. institute of Geology and Mineral Resources, {4. 2.0016, China 4.State Key Laboratory of Loess and Quaternary Geology, institute of Earth Environment, chinese academy of sciences, Xi’an 710075, China 5 State Key Laboratory for Mineral Deposits Research, Department of Earth sciences, {4. University, {4. 2.0093, China 1. Qinghai institute of Salt Lakes Chinese Academy of Sciences Xining 810008 China 2. State Key Laboratory of Environmental Geochemistry Institute of Geochemistry Chinese Academy of Sciences Guiyang 550002 China 3. nanjing institute of Geology and Mineral Resources 210016 Nanjing China 4. State Key Laboratory of Loess and Quaternary Geology Institute of Earth Environment Chinese Academy of Sciences Xi’an 710075 China 5. State Key Laboratory for Mineral Deposits Research Department of Earth Sciences Nanjing University Nanjing 210093 China

A laboratory inorganic carbonate precipitation experiment at high pH of 8.96 to 9.34.was conducted, and the boron isotopic fractionations of the precipitated carbonate were measured. The data show that boron isotopic fractionation factors (αcarb-3) between carbonate and B(OH)3 in seawater range 0.937 and 0.965, with an average value of 0.953. Our results together with those reported by Sanyal and collabo-rators show that the αcarb-3 values between carbonate and B(OH)3 in solution are not constant but are negatively correlated with the pH of seawater. The measured boron isotopic compositions of carbonate precipitation (δ11Bcarb) do not exactly lie on the best-fit theoretical δ 11B4.pH curves and neither do they exactly parallel any theoretical δ 11B4.pH curves. Therefore, it is reasonable to argue that a changeable proportion of B(OH)3 with pH of seawater should also be incorporated into carbonate except for the dominant incorporation of B(OH)4. in carbonate . Hence, in the reconstruction of the paleo-pH of sea-water from boron isotopes in marine biogenic carbonates, the use of theoretical boron isotopic frac-tionation factor (α4.3) between B(OH)4. and B(OH)3 is not suitable. Instead, an empirical equation should be established.

关键词： boron isotopic fractionation biogenic carbonate B(OH)3 incorporation

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Late Jurassic and Early Cretaceous Radiolarians from Zhilong,Gyangse,Tibet

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地学前缘 2009年第S1期16卷 275-276页

作者： Bo Xu,Hui Luo nanjing institute of Geology and Palaeontology,chinese academy of {4.,nanjing 2.0008,China.

Abundant well-preserved Late Jurassic-Early Cretaceous radiolarian fossils were extracted from 31 bedded green chert samples collected from Zhilong section,Gyangse,southern ***

关键词： Late Jurassic Early Cretaceous radiolarians Zhilong Gyangse Tibet

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Speciation of the genus Arthricocephalus Bergeron, 1899 (Trilobita) from the late Early Cambrian and its stratigraphic significance

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Progress in Natural Science:Materials International 2006年第6期16卷 614-623页

作者： YUAN Jinliang, ZHAO Yuanlong and YANG Xinglian (nanjing institute of Geology and Palaeontology, chinese academy of sciences, nanjing {4.008, China College of Resource and Environment of Guizhou University, Guiyang 550003, China) [a] nanjing institute of Geology and Palaeontology Chinese Academy of Sciences Nanjing China [b] College of Resource and Environment of Guizhou University Guiyang China

The genus Arthricocephalus Bergeron, 1899 is revised, and Halipanktos Balker & Peel, 1997 is suggested here as a senior synonym. The subgenus Arthricocephalus (Arthricocephalites) Chien & Lin in Lu et al. , 1974.is considered as a separate genus. Of the 20 previously assigned species of Arthricocephaius (Arthricocephalus) Bergeron, 1899, Arthricocephalus (Arthricocephalites) Chien & Lin in Lu et al. , 1974. Arthricocephalus (Euarthricocephalus) Ju, 1983 are lumped into eight species. The speciation trend of Arthricocephalus and Arthricocephalites is demonstrated based on their stratigraphic occurrences. It not only enhances the resolution of the biostatigraphic zonation in the uppermost Lower Cambrian, but also represents a potential candidate to define the Duyunian stage. The base of the stage is suggested at the first appearance datum (FAD) of Arthricocephalus chauveaui Bergeron, 1899 within the evolutionary lineage from Ar. jiangkouensis Yin in Yin & Li, 1978 to Ar. chauveaui in a global scale.

关键词： late Early Cambrian Duyunian stage speciation of Arthricocephalus and Arthricocephalites biostratigraphy.

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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 10004., China 3 Graduate University of the chinese academy of sciences, Beijing 10004., China 4.Department of Physics, {4. Normal University, {4. 2.0011, China 1. Key Laboratory of Optical Astronomy National Astronomical Observatories Chinese Academy of Sciences Beijing 100012 China2. Key Laboratory for Particle Astrophysics Institute of High Energy Physics Chinese Academy of Sciences Beijing 100049 China3. Graduate University of the Chinese Academy of Sciences Beijing 100049 China4. Department of Physics Nanjing Normal University Nanjing 210011 China

A sample consisting of 211 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

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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 {4.04., China 2. institute of Geographic sciences and Natural Resources Research, chinese academy of sciences, Beijing 100101, China nanjing Inst Meteorol Dept Geog Nanjing 210044 Peoples R China chinese Acad Sci Inst Geog Sci Beijing 100101 Peoples R China chinese Acad Sci Nat Resources Res Beijing 100101 Peoples R 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 30 years data from 4.2 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.

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SOTER-Based Soil Water Erosion Simulation in Hainan Island

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Pedosphere 2003年第2期13卷 139-146页

作者： ZHAO YUGUO, ZHANG GANLIN and GONG ZITONGinstitute of Soil Science, the chinese academy of sciences, nanjing 2.0008 (China) institute of Soil Science the Chinese Academy of Sciences Nanjing 210008 (China)

The actual and potential water erosion rates of soils with different landcovers in Hainan Island, China, were estimated based on the universal soil loss equation (USLE) anda 1:2.0000 Soils and Terrain Digital Database (SOTER) database, from which soil water erosionfactors could be extracted. 92.8% of the whole island had a current erosion rate of lower than 500 tkm^(-2) a^(-1). Soil erosion risk was considered to be high because of its abundant *** vegetation cover, the potential soil erosion rate would be extremely high and 90.8% of theisland would have a soil erosion rate higher than 2.00 t km^(-2) a^(-1). Relative erosionvulnerability of different soil zones, landform types, and lithological regions of the island wascompared by introducing a relative erosion hazard parameter a. Cambosols developed from siltstoneand mudstone in low hill regions were pinpointed as soils with the highest erosion risk in theisland.

关键词： hainan island soil erosion risk assessment SOTER USLE

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Sustainable Nutrient Management in chinese Agriculture: Challenges and Perspective

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Pedosphere 2006年第2期16卷 253-263页

作者： GAO Chao SUN Bo ZHANG Tao-Lin Department of geography Nanjing University Nanjing 210093 （China）. institute of Soil Science Chinese Academy of Sciences Nanjing 2100（78 （China）

China has to raise agricultural productivity in its limited and shrinking farmland to guarantee food security for its huge and ever-growing population. Sustainable soil nutrient management is of paramount importance to the world's most populous country. Critical challenges the country is facing in sustaining soil fertility and in alleviating the hazardous impact of intensive fertilizer use are discussed in this paper. It is emphatically pointed out that national strategies as well as area-specific action plans with respect to scientific nutrient management are urgently needed to balance productivity and sustainability in the future. Relevant proposals for addressing those challenges are also presented.

关键词： China food security nutrient management soil fertility water quality

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Geochemical Forms of Phosphorus in Sediments of Three Large, Shallow Lakes of China

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Pedosphere 2006年第6期16卷 726-734页

作者： ZHU Guang-Wei QIN Bo-Qiang ZHANG Lu LUO Lian-Cong nanjing institute of geography and limnology Chinese Academy of Sciences Nanjing 210008 China

A sequential extraction method for the fractionation of phosphorus （P） in lake sediments was used to analyze phos- phorus fractions of sediments taken from three large, shallow. eutrophic freshwater lakes of China-Talhu Lake. Chaohu Lake, and *** Lake. All three lakes are located in the lower reaches of the Changjiang River （Yangtze River）. In Taihu Lake and Chaohu Lake, algae blooms occurred every year, while Longgan Lake was a macrophyte-dominated lake. Results showed that exchangeable phosphorus fractions were much higher in the eutrophic lake sediments than in the macrophyte-flourishing lake sediment. Also, the ratio of Fe：P in the sediments of the algae-predomlnant lakes was generally much lower than that in the macrophyte-predominant lakes. Thus, the geochemical fractions of phosphorus in sediments had a closer relationship with the type of aquatic vegetation.

关键词： algal bloom macrophyte phosphorus sediment shallow lakes

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Sources of Cretaceous Bimodal Volcanic Rocks in the Coastal Region of Southeastern China -- Constrains of the Sr content and its isotopes

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Acta Geologica Sinica(English Edition) 1999年第1期73卷 84-92页

作者： XING Guanfu YANG Zhuliang and TAO Kuiyuan nanjing institute of Geology and Mineral Resources, chinese academy of Geological {4.,534.East Zhongshan Road, nanjing 2.0016 chinese Acad Geol Sci Nanjing Inst Geol & Mineral Resources Nanjing 210016 Peoples R China

Cretaceous volcanism in the coastal region of southeastern China was characteristized by occurrenceof bimodal volcanics consisting of basalts and rhyolites, the geneses of which are still controversial. Based on the factthat their isotopic compositions are similar but the Sr content of the former is much higher than that of the latter, thispaper discusses the respective sources of the two end-member rocks, and concludes that basalts were derived fromthe subduction-related enriched upper mantle wedge and their isotopic compositions had not been affected by crustalassimilation, whereas rhyolites were formed by remelting of the old metamorphic basement, but they were mixed upwith the underplating basaltic magmas to various degrees so that their Sr isotopic compositions varied significantlyfrom the sources and tended to be homogeneous to the latter.

关键词： Sr content and its isotopes Cretaceous bimodal volcanics coastal region of southeastern China

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Geophysical survey on the tectonic and sediment distribution of Qinghai Lake basin

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Science China Earth sciences 2006年第8期49卷 851-861页

作者： AN Zhisheng1, WANG Ping2, SHEN Ji3, ZHANG Yixiang2, ZHANG Peizhen4. WANG Sumin3, LI Xiaoqiang1, SUN Qianli1, SONG Yougui1, AI Li1, ZHANG Yechun2, JIANG Shaoren2, LIU Xingqi3 & WANG Yong31. institute of Earth Environment, chinese academy of sciences (CAS), Xi’an 710075, China 2. South China Sea institute of Oceanology, CAS, Guangzhou 510301, China 3. nanjing institute of geography and limnology, CAS, nanjing 2.0008, China 4. institute of Geology, China Earthquake Administration, Beijing 100029, China 1. institute of Earth Environment Chinese Academy of Sciences (CAS) Xi’an 710075 China 2. South China Sea institute of Oceanology CAS Guangzhou 510301 China 3. nanjing institute of geography and limnology CAS Nanjing 210008 China 4. institute of Geology China Earthquake Administration Beijing 100029 China

The intensive geophysical survey of Qinghai Lake reveals the buried depth of lake sediments and their distribution features. The result indicates that there are three important inter- phases of Qinghai Lake sediments: T1 is the rife interphase of the lake, above which sediments are spread all over the lake basin with roughly the same thickness; T5 is the interphase from which the neotectonic sedimentary cycle begins, and its above sedimentary environment is relatively stable; Tg is the base of the lake basin. Five west-northwest (WNW) fault belts defined the tectonic structure of Qinghai Lake basin: the central hunch around Haixin Shan with two subbasins both in its north and south. The thickness of the lake sediments varies at different places, the thickest sediments are found within the two subbasins. According to the depth that the Sparker System can reach, sediment in the northern subbasin is deeper than 560 m, while sediment in the southern subbasin is deeper than 700 m. The correlation between the seismic sequence stratigraph and the lithology of onshore core shows that Qinghai Lake sediments consist of muddy silt, clay silt, silty clay, gravel silty clay, etc.

关键词： sediment, geophysical survey, Qinghai Lake.

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