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Concentration Characteristics and Sources of Chemical Elements in Atmospheric Fine Particles (PM_(2.5)) in Autumn in Xi'an City

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Meteorological and Environmental Research 2011年第4期2卷 5-8页

作者： GAN Xiao-feng1,2, CAO Jun-ji2,3. WANG Qi-yuan4, SHEN Zhen-xing4, XU Hong-mei2 1. department of Environmental Science and Technology, Xi’an Jiaotong university, Xi’an 710049, China 2. State Key Laboratory of Loess and Quaternary geology, Institute of Earth Environment, Chinese Academy of Sciences, Xi’an 710075, China 3. Institute of Global Environmental Change, Xi’an Jiaotong university, Xi’an 710049, China 4. department of Environmental Engineering, Xi’an Jiaotong university, Xi’an 710049, China

[Objective] The aim was to study the concentration characteristics and sources of chemical elements in atmospheric fine particles (PM2.5) in autumn in Xi’an City. [Method] By means of mini-volume sampler, PM2.5 samples in atmosphere in Xi’an were collected in October 2009, and the concentration characteristics and sources of elements in PM2.5 were analyzed. [Result] The average mass concentration of PM2.5 in atmosphere in autumn in Xi’an City was 168.44 μg/m3.which was higher than that of Beijing and Pearl River Delta area, and the minimum and maximum value were 53.29 and 3.8.16 μg/m3. respectively. The mass concentration of S, Zn, K, Cl, Ca and Fe in PM2.5 was above 1.0 μg/m3. being at high pollution level. In addition, K had obvious correlation with organic carbon (OC) and element carbon (EC), with the correlation coefficients of 0.76 and 0.75 (Pmn and Cr mainly came from earth crust, rock weathering and other natural sources, while anthropogenic pollution sources had great effects on S, Zn, Cl, Pb, Br, Mo, Cd and As which were affected by soil dust and other natural sources slightly, and Cd had the highest enrichment factor and mainly came from metal smelting. In a word, coal combustion, biomass burning, vehicle emissions, metallurgical, chemical industry and dust were the main sources of PM2.5 in autumn in Xi’an. [Conclusion] The study could provide theoretical foundation for the control of urban environmental pollution.

关键词： Atmospheric fine particles Chemical element Enrichment factor Factor analysis China

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fMRI revealed neural substrate for reversible working memory dysfunction in subclinical hypothyroidism

fMRI revealed neural substrate for reversible working memory...

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中国神经科学学会第四次会员代表大会暨第八届全国学术会议

作者： De-Fa ZHU~(1,*),Zhao-Xin WANG~(2,6,*),Da-Ren ZHANG~2,Zhong-Lin PAN~3.Sheng HE~4,Xiao-Ping HU~5,Xiang-Chuan CHEN~(2,*), Jiang-Ning ZHOU~(2,*) 1 department of Endocrinology,Anhui Geriatric Institute,the First Affiliated Hospital of Anhui Medical university, Hefei 23.022,China 2 Hefei National Laboratory for Physical Science at Microscale,and School of Life Science,university of Science and Technology of China,Hefei,23.027,China 3.department of Radiology,PLA 105 hospital,Hefei,23.03.,China 4 department of Psychology,university of minnesota,minneapolis,mn 55455 5 department of Biomedical Engineering,Georgia Tech and Emory university,Atlanta,GA 3.3.2 6 Guangdong Key Lab of Medical Molecular Imaging,Shantou university Medical College,Shantou,515041,China

＜正＞Cognitive impairment has been found in thyroid hormone-related diseases（e.g.,hyperthyroidism and hypothyroidism） for a long ***,whether and how subclinical hypothyroidism（SCH） causes any deficits in brain functions,and whether a hormone replacement treatment is necessary for SCH patients,still remain controversial subjects. In the present study,functional magnetic resonance imaging（fMRI） was used to measure brain functions by asking euthyroid subjects,hyperthyroid patients,and SCH patients to perform the widely used digit n-back working memory task. After having been treated with L-thyroxine for about six months,the SCH patients were asked to do the same fMRI *** hypothyroid and SCH patients scored significantly lower in the 2-back task than either the hyperthyroid patients or the euthyroid subjects（P ＜ 0.012）.The fMRI showed that a common fronto-parietal network,including bilateral middle / inferior frontal gyri（M/IFG）,bilateral dorsolateral prefrontal cortex（DLPFC）,bilateral premotor areas（PreMA）,the supplementary motor area / anterior cingulate cortex（SMA/ACC）,and bilateral parietal areas（PA）,was activated by the nback task in all the *** quantitative analysis showed that the load effect of BOLD response appeared in all the five regions of interest（ROIs） in the euthyroid and hypothyroid *** the pre-treatment SCH patients,however,the load effect of BOLD response was only found in the PA and PreMA,but not in other frontal cortex ROIs（GLM,F ＜ 2.6,P ＞ 0.1）.After an approximately six-month treatment with LT4,the SCH patients exhibited the same load effects in all five ROIs as the euthyroid subjects（GLM,F ＞ 6,P ＜ 0.05） along with an improvement of performance in N-back *** results suggest that working memory（but not other memory functions） is impaired in SCH patients,mainly as far as disorders of the fronto-parietal network were *** the memory performance and frontal executive functions were improved after a

关键词： working memory functional magnetic resonance imaging(fMRI) frontal cortex subclinical hypothyroidism(SCH) L-thyroxine treatment

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Liable content of elements in karst ecological environments in south China-A case study in Nongla,Guangxi

Liable content of elements in karst ecological environments ...

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The First International Conference on Sustainable Development in Karst Regions & International Working Group Meeting of IGCP 448 World Correlation of Karst Ecosystems

作者： JIANG Zhongcheng (Institute of Karst geology,CAGS, Guilin,China,54100)ZHANG Dian ( department of Geography of the university of Hong Kong)

Study on liable content of elements in karst environments, one should consider soil, karstwater and soil water three kinds of carriers. Though the alkaline and cretaceous features of soilsin karst areas result in the low labile content of alkaline-earth elements in soil, the ionicconcentration of elements in karst water and soil water can make up the lack in some karst areas andbecome the important sources of liable elements for vegetation. Moreover, the liable content ofelements in soil, karst water and soil water is quite different in different rock areas and karst dynamicconditions. With the solution of rocks, the higher background value of elements in rock usually leadsto the higher liable content in karst areas. There are intense karst solution processes in Nongla, *** a result, not only soluble K, Na, Ca and Mg can be dissolved in water in greatconcentration, but also some un-soluble elements such as Si, Al, Fe and mn can be partly dissolved inkarst water and soil water, which make the vegetation to develop well, with diverse plant species andmany precious herbs.

关键词： liable element karst ecology karst mountains in south China.

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Cryptomelane(Kxmn(8-x)O(16)) Natural active octahedral molecular sieve(OMS-2)

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Chinese Science Bulletin 2003年第9期48卷 920-923页

作者： LU Anhuai, GAO Xiang, QIN Shan & WANG Changqiudepartment of geology, Peking university, Beijing 100871. China Correspondence should be addressed to Lu Anhuai (e-mail: ahlu@ ***) department of geology Peking University Beijing 100871 China

The Xiangtan manganese deposit (XTM) used to be considered a supergene oxide manganese ore in South China. We reported a new identification of the naturally outcropping cryptomelane by examining the physical, chemical and structural features of the XTM supergene oxide manganese ore. The mnO2 content was over 90%, K2O more than 3., and water from 2.2%-3.1% which is similar to one in zeolite. The cell parameters of the cryptomelane were given as a0 = 0.9974 nm, b0 = 0.2863.nm, c0 = 0.9693.nm and β91.47(. There was a larger pseduotetragonal tunnel in the natural cryptomelane that was formed by [mnO6] octahedral double chains with aperture of 0.462×0.466 nm2, filled with K cations resulting in some mn3. substituting for mn4+ to balance the negative charges of structure. The finding is important not only for prospecting manganese resources in South China, but also in application of octahedral molecular sieve of natural cryptomelane as that developed in the tetragonal molecular sieve of natural zeolite over the past century. The XTM cryptomelane (OMS-2) may be the real mineral of the active octahedral molecular sieve in nature.

关键词：隐钾锰矿天然活性分子筛 OMS-2 湘潭锰沉积物浅生矿床氧化物

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Hydrothermal origin of elevated iron,manganese and redox-sensitive trace elements in the c.63. Ma Doushantuo cap carbonate

Hydrothermal origin of elevated iron,manganese and redox-sen...

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中国科学院地质与地球物理研究所第11届（2011年度）学术年会

作者： JING HUANG~(1,2),XUELEI CHU~(1,2*),GANQING JIANG~3.LIANJUN FENG~1 & HUAJIN CHANG~4 1 Institute of geology and geophysics,Chinese Academy of Sciences,Beijing 100029,China 2 State Key Laboratory of Lithospheric Evolution,Beijing 100029,China 3.department of Geoscience,{3. of Nevada,Las Vegas,NV 89154-4010,usa 4 School of Life and Geography Sciences,Qinghai Normal {3.,Key Laboratory of Tibetan Plateau Environment and Resources,Ministry of Education,Xining 810008,China

Major and trace element,including REE,concentrations of the Doushantuo cap carbonate(c. 63. Ma) in South China show enrichment in Fe,mn and redox-sensitive elements and slightly negative Ce anomalies,indicating anoxic environments during cap carbonate *** Fe/Al ratios but very low concentration of extractable pyrites suggest ferruginous rather than euxinic *** REE + Y patterns of samples show enrichment of heavy REE(HREE),positive Eu anomalies and positive Y anomalies,implying a hydrothermal origin for elevated concentration of Fe,mn and redox-sensitive *** results suggest that ferruginous Ediacaran oceans may have rooted from hydrothermally induced iron accumulation in severely glaciated Cryogenian oceans.

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Origin of palaeo-waters in the Ordovician carbonates in Tahe oilfield,Tarim Basin:constraints from fluid inclusions and Sr C and O isotopes

Origin of palaeo-waters in the Ordovician carbonates in Tahe...

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中国科学院地质与地球物理研究所第11届（2011年度）学术年会

作者： K.LI~(1,2),C.CAI~1,H.HE~3.L.JIANG~(1,2),L.CAI~(1,2),L.XIANG~(1,2),S.HUANG~4 and C.ZHANG~5 ~1Key Lab of Petroleum Resources,Institute of geology and geophysics,Chinese Academy of Sciences,Beijing,China ~2Graduate university of Chinese Academy of Sciences,Beijing,China ~3.nstitute of Petroleum Exploration and Development,CENOPEC, Beijing,China ~4State Key Lab Oil Gas Reservoir geology and Exploitation,Institute of Sedimentary geology,Chengdu university of Technology,Chengdu,China department of Geochemistry,Yangtze university,Jingzhou,Hubei,China

Petrographic features,isotopes,and trace elements were determined,and fluid inclusions were analyzed on frac-ture -filling,karst-filling and interparticle calcite cement from the Ordovician carbonates in Tahe oilfield,Tarim basin,NW *** aim was to assess the origin and evolution of palaeo-waters in the *** initial water was seawater diluted by meteoric water,as indicated by bright cathodoluminescence(CL) in low-tempera-ture *** palaeoseawater was further buried to temperatures from 57 to 110℃,nonluminescent calcite precipitated during the Silurian to middle *** of meteoric water of late Devonian age into the carbonate rocks was recorded in the first generation of fracture- and karst-filling dull red CL calcite with temperatures from3.,low salinities(mn contents and high Sr/Sr ratios from 0.7090 to *** the early Permian,Sr-rich hydrothermal water may have entered the carbonate rocks,from which precipitated a second generation of fracture-filling and interparticle calcite and barite cements with salinities greater than 22.4 wt%,and temperatures from 120°C to 180°*** hydrothermal water may have collected isotopically light CO(possibly of TSR-origin) during upward migration,resulting in hydrothermal calcite and the present-day oilfield water havingδC values from -4.3.to -13.8‰and showing negative relationships of Sr/Sr ratios toδC andδO ***,higher temperatures(up to 187℃) and much lower salinities (down to 0.5 wt%) measured from some karst-filling,giant,nonluminescent calcite crystals may suggest that hydrothermal water was deeply recycled,reduced(Fe-bearing) meteoric water heated in deeper strata,or water generated from TSR during hydrothermal water *** of hydrothermal and local basinal water(or diagenetically altered connate water) with meteoric waters of late Permian age and/or later may have resulted in large variations in salinity of the present oilfield waters with

关键词： carbon isotopes carbonates fluid inclusion fracture-filling hydrothermal water strontium isotopes Tarim basin

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橄榄石-硅镁石多体系列晶格的系统畸变

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矿物学报 1987年第2期 97-106页

作者：薛纪越南京大学地质系

作者从文献资料中收集了27个橄榄石族和硅镁石族矿物及类似物的成分和晶胞参数数据。通过多元回归分析,发现该多体系列的晶格存在着系统的畸变。如晶格的畸变用根据晶胞参数推导而来的四个参数Ra、Rb、Rc和γh来描述,则这些参数随二价... 详细信息

作者从文献资料中收集了27个橄榄石族和硅镁石族矿物及类似物的成分和晶胞参数数据。通过多元回归分析,发现该多体系列的晶格存在着系统的畸变。如晶格的畸变用根据晶胞参数推导而来的四个参数Ra、Rb、Rc和γh来描述,则这些参数随二价阳离子平均半径〈r〉和四面体空隙被Si占位的比例TSi的变化而变化,并可用下列方程表示它们之间的数学关系:Ra=0.3.66〈r〉+0.2251TSi+1.1706;Rb=0.6200〈r〉-0.9251TSi+1.0651;Rc=0.6753.r〉+0.513.TSi+0.943.;γh=2.2051〈r〉+20.5117TSi+116.2924。作者还对上述四个方程的晶体化学意义作了解释,并用该多体系列之外的以六方紧密堆积为基础的淡硅锰石和羟硅锰石的晶胞参数,对这四个方程作了成功的检验。

关键词：橄榄石族矿物硅镁石族矿物多体系列晶格畸变

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Towards Understanding Paleosols in Southern Levantine Eolianites:Integration of Micromorphology,Environmental Magnetism and Mineralogy

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Journal of Mountain Science 2009年第2期6卷 113-124页

作者： Alexander Tsatskin Tatyana S.Gendler Friedrich Heller Igal Dekman Gitti L.Frey Laboratory of geology Zinman Institute of Archaeology University of HaifaHaifa 31905 Israel United Institute of Physics of the Earth RAS Bolshaya Gruzinskaya 10Moscow 123810 Russia Institut für Geophysik ETH ZürichCH-8092 Zürich Switzerland department of Materials Engineering Technion Haifa 32000 Israel

The paper addresses the controversial question of the role of clay-sized dust in the formation of paleosols in coastal eolianites, Israel. At the Habonim type section, the pedocomplex dated by archaeology and luminescence to 45-13. ka ago shows at least three paleosols, not separated by non-soil sediments. The oldest reddish paleosol （apparently related to MIS 5） is magnetically enhanced, leached from carbonates, with signs of bioturbation and strongly aged clay coatings. The reddening is due to very fine, -20 nm, poorly crystallized, superparamagnetic （SP） hematite, as determined by Mossbauer studies. In subsoil, lithorelics of eolianite are found. Over time, the soil surface aggraded due to accelerated fine dust accumulation alongside local slope wash. On younger materials formed magnetically depleted vertisols, dominated by smectite-type expandable paramagnetic clays. In thin sections, vertisols exhibit strong stipple-speckled and striated b-fabric due to shrink-swell processes, impregnative calcite nodules and Fe-mn redistribution. The uppermost hydric vertisol shows the strongest expression of juxtaposed features of recurrent calcite and Fe precipitation. This paleosol developed on colluvial soil materials, as evidenced by mixing of clay coated and uncoated grains of quartz and calcite allochems. M6ssbauer spectra show high amounts of Fe（III） incorporated in the clay structure, low amounts of SP goethite and absence of SP hematite. Whilst magnetic susceptibility drops in vertisols to minimal values, increase. The latter along ferrimagnetie grain sizes with differences in the hierarchy of microfabric features is taken as indication for lithologic discontinuities which may have resulted from continuous, albeit variable and low-intensity, input of eolian clay from both remote Saharan and local sources, roughly dated to the earlier to middle part of the Last Glacial.

关键词： Coastal sand loess deposition microfabrie hierarchy magnetic enhancement paramagnetic phyllosilicates MSssbauer effect

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Cryptomelane(Kxmn8-xO16) Natural active octahedral molecular sieve（OMS-2）

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Science Bulletin 2003年第9期 920-923页

作者： LU Anhuai, GAO Xiang, QIN Shan & WANG Changqiu department of geology, Peking university, Beijing 100871. China Correspondence should be addressed to Lu Anhuai (e-mail: ahlu@ ***)

The Xiangtan manganese deposit (XTM) used to be considered a supergene oxide manganese ore in South China. We reported a new identification of the naturally outcropping cryptomelane by examining the physical, chemical and structural features of the XTM supergene oxide manganese ore. The mnO2 content was over 90%, K2O more than 3., and water from 2.2%-3.1% which is similar to one in zeolite. The cell parameters of the cryptomelane were given as a0 = 0.9974 nm, b0 = 0.2863.nm, c0 = 0.9693.nm and β= 91.47°. There was a larger pseduotetragonal tunnel in the natural cryptomelane that was formed by [mnO6] octahedral double chains with aperture of 0.462×0.466 nm2, filled with K cations resulting in some mn3. substituting for mn4+ to balance the negative charges of structure. The finding is important not only for prospecting manganese resources in South China, but also in application of octahedral molecular sieve of natural cryptomelane as that developed in the tetragonal molecular sieve of natural zeolite o

关键词： cryptomelane natural octahedral molecular sieve xiangtan manganese deposit.

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滦河口区沉积物中元素的分布和环境的关系

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海洋通报 1983年第2期 60-70页

作者：周福根同济大学海洋地质系

滦河横贯河北省北部,全长1200公里,流域面积约45000平方公里,年平均迳流量为45.5亿立方米,每年把约1900万吨泥沙输入渤海,平均含沙量仅次于黄河而高于长江。大量泥沙堆积于河口外的浅海中,形成扇状三角洲。同时在河口外海域的东和东北... 详细信息

滦河横贯河北省北部,全长1200公里,流域面积约45000平方公里,年平均迳流量为45.5亿立方米,每年把约1900万吨泥沙输入渤海,平均含沙量仅次于黄河而高于长江。大量泥沙堆积于河口外的浅海中,形成扇状三角洲。同时在河口外海域的东和东北强风浪(最大风速可达20米/秒)的作用下,沿岸形成了一系列的滨岸沙坝,类似墨西哥湾西岸的里奥·格兰德(Rio Grande)河口。

关键词：曹妃甸周福沙坝河床地形沉积物样品浅滩水动力滨岸富集有孔虫权系数地质系河槽河床

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