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Variation of the Fe/Mn ratio of ferromanganese crusts from the Central North Pacific: implication for paleoclimate changes

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Progress in Natural Science:Materials International 2005年第6期15卷 530-537页

作者： LU Zunli1**, LING Hongfei1*, ZHOU Feng1, JIANG Shaoyong1, CHEN Xiaoming1 and ZHOU Huaiyang2(1. State Key Laboratory for Mineral Deposits Research, department of earth sciences, Nanjing {3., Nanjing 210093. china 2. guangzhou Institute of Geochemistry, Chinese Academy of sciences, guangzhou 510640, china)department of earth & Environmental Science, {3. of Rochester State Key Laboratory for Mineral Deposits Research Department of Earth Sciences Nanjing University Nanjing 210093 China department of earth & Environmental Science University of Rochester guangzhou Institute of Geochemistry Chinese Academy of Sciences Guangzhou 510640 China

Contents of Fe, Mn and other elements in four ferromanganese crusts recovered from the central North Pacific are analyzed at high depth-resolution by electron microprobe for reconstructing factors controlling their deposition. Manganese (IV) in hydrogenetic ferromanganese crusts is mainly supplied as colloidal precipitates from the Oxygen Minimum Zone (OMZ), which concentrates high amounts of dissolved Mn (II). The iron is derived from carbonate dissolution and silicate particles of eolian dust. An increase in paleoproductivity during cooler climate would potentially lead to a decrease in Mn deposition due to enlargement of the OMZ which has a “temporary storage” effect for Mn. On the other hand, not affected by the OMZ, the iron entering the Fe-Mn crust would likely increase with the eolian dust input and surface productivity at glacial stages. As a result, the increasing Fe/Mn ratio should indicate a cooling climate. This is supported by the following observations. In the profile of the past 1 Ma, the variations of Fe/Mn ratio coincide with benthic oxygen isotope fluctuation in glacial-interglacial cycles. Three episodes with high Fe/Mn ratios, approximately at 2.6, 1.8 and 0.8 Ma, are detected within the past 3.Ma and coincide with major climate transitions and cooling events. The secular evolution pattern of Fe/Mn ratio in the Cenozoic is similar to the Pb isotope evolution which is mainly controlled by eolian dust and related to climate. The Fe/Mn evolution pattern is also broadly consistent with the global deep-sea oxygen isotope records. Therefore, Fe/Mn ratio recorded in the ferromanganese crusts may be a new proxy for climate change.

关键词： Fe/Mn ratio ferromanganese crust central North Pacific paleoclimate.

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Orthogonality in Banach spaces and orthogonal multiscale L^1-approximation

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Chinese Science Bulletin 1999年第1期44卷 25-35页

作者： YANG Lihuadepartment of Scientific Computing and Computer Applications, School of Mathematics and Computing Science, zhongshan (Sun Yatsen) university,{3., china Institute of Mathematics, Chinese Academy of sciences, Beijing 100080, china department of Scientific Computing and Computer Applications School of Mathematics and Computing Science Zhongshan (Sun Yatsen) University Guangzhou China Institute of Mathematics Chinese Academy of Sciences Beijing China

The orthogonality in Hilbert spaces is extended to the general Banach spaces and a concrete shift-invariant orthogonal family in L^1(R) is constructed. The corresponding projection approximation theorems and the algor... 详细信息

关键词： Banach spaces orthogonality approximation multiscale analysis.

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A comparison analysis between developed and undeveloped depressions over the South china Sea

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Acta Oceanologica Sinica 1989年第2期8卷 199-208页

作者： Liang Biqi Zhang Qiuqing department of Atmospheric sciences, zhongshan university, {3., china National Research Center for Marine Environment Forcasts, Beijing, china Dept. of Atmospheric sciences Zhangshan Univ. Guangzhou China. China

-- In this paper, by using two sets of composite data of developed and undeveloped depressions over the South china Sea, we analyze and compare the dynamic structures, the heating fields and the vorticity budget residuals of two different types of depressions. Our conclusions are as follows:The two types of depressions are similar in thermodynamical and dynamical structures. The main differ ences are : in the high layer of developed depression there is a divergence field, with a center near the zero line of vertical wind shear, and over undeveloped depression, the divergence field is weaker and the vertical wind at its center is greater than 5 m s-1. The thermodynamical field of the former is asymmetrical and that of the latter is quasi - symmetrical. As far as the dynamics structure is concerned, the convergence in the lower layer and the difference of divergence between the upper and lower layers of developed depression is three tmies larger than that of undeveloped depression. The upward motion and heating field at the center of developed depression is also stronger than that of undeveloped *** vorticity budget of the two types of depressions is mainly determined by the divergence term, the vorticity advection term and the vertical transport term. The residual term is also *** principal contribution comes from the divergence term . This is more significant for developed depression than for undeveloped depression.

关键词： over A comparison analysis between developed and undeveloped depressions over the South china Sea

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Resistless photochemical etching of a silicon wafer by UV laser with an H_2O_2 and HF aqueous solution

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Chinese Science Bulletin 2002年第2期47卷 164-167页

作者： YANG Jie, LIU Yanfa & M. Murahara State Key Laboratory of Ultrafast Spectroscopy of zhongshan university, guangzhou 510275, china {3. of Electrical Engineering of Tokai university, Japan State Key Lab. Ultrafast Spectrosc. Zhongshan University Guangzhou 510275 China

A new resistless etching method has been de-veloped for Silicon wafers. This new method uses an aqueous solution consisting of hydrogen peroxide (H2O2) and hydro-gen fluoride (HF) as the activating etchants. A 193.nm ArF excimer laser and a 266 nm fourth harmonic generation Nd:YAG laser were used as the photon sources. Results showed that pattern etching has been achieved without any photoresist film. In the case of the 193.nm laser, the optimal etching appeared at a 1.3.H2O2/HF ratio, where an etchdepth of 210 nm was achieved with a fluence of 29 mJ/cm2 and shot number of 10000. At the same conditions, the etch depth with H2O2 and HF solution was three times of that by using H2O and HF mixture. In the case of the 266 nm Nd : YAG laser, the optimal etching appeared at twice ratio of H2O2/HF, where the etch depth of 420 nm was achieved witha fluence of 12 mJ/cm2 and shot number of 3.000. Results showed that the etch effect of the 266 nm Nd : YAG laser was more desirable than that of the 193.nm ArF

关键词： UV laser resistless photochemical etching hydrogen peroxide (H2O2).

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Leaching experiment research on host rocks of Qiaogashan gold deposit in Shanshan County, Xinjiang, china

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Chinese Science Bulletin 1999年第S2期44卷 216-218页

作者： ZHAI Wei, YANG Rongyong, LI Zhaolin and WU Jianjun department of earth sciences, Zhougshan {3., guangzhou 510275, china State Key Laborntory of Metallogenesis, Nanjing {3., Nanjing 210093. china

1 Geological setting of the deposit THE Qiaogashan gold deposit is located at contact zone of middle Tianshan terrance and south Tianshanback-arc basin, and near the latter side. The orebodies are controlled by middle Tianshan brittle-ductileshear zone. The main ore types are auriferous quartz veins and fractured and alterated rocks. The southpart of the deposit is hosted in striking sheared Devonian rocks, while the north part in a diorite body,which was deformed by a nape shear zone. 2 Geology and geochemistry of host rocks The host rocks of south part of the deposit are Devonian detrital stone of terrigenous origin, interlayering volcanic detrial stone of back-arc basin facies, which locally suffered intensive ductile-brittle shearing. The rock type is composed mainly of gray-green siltstone, poststone, metasiltstone, etc., and a se-

关键词： leaching experiment host rocks Qiaogashan gold deposit Xinjiang.

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Landscape ecological analysis of urban vegetation in guangzhou,china

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Journal of Environmental sciences 1999年第2期11卷 33-39页

作者： Guan Dong sheng, Wang Li rong, Li Zhen College of earth & Environment Science, zhongshan university, guangzhou 510275,{3.

The compositions, patches and landscape heteorogentity of guangzhou urban vegetation are studied by using the principles of landscape ecology in this paper. The results showed that the area of urban vegetation was 26901 4hm 2, and the distribution of vegetation types and regional vegetation coverage were uneven. The patch areas of vegetation were large in scenery vegetation and shelter vegetation, and small in street corner vegetation and small garden vegetation. Most of patches fell in range between 100 and 10000 m 2. Only 1.13. of patches were larger than 1000000 m 2. Structure features of vegetation landscape in old urban areas were small patch, high scattering degree, high diversity, random distribution of vegetation patches and high heterogeneity. In new urban areas, the features were big patches, fine planning, medium landscape heterogeneity. Some suggestions are made according to landscape character of urban vegetation in guangzhou.

关键词： landscape ecology heterogeneity urban vegetation guangzhou.

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Zircon SHRIMP U-Pb geochronology and petrogenesis of the plagiogranites from the Lagkor Lake ophiolite,Gerze,Tibet,china

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Chinese Science Bulletin 2007年第5期52卷 651-659页

作者： ZHANG YuXiu1,2, ZHANG KaiJun1,3. LI Bing1,2, WANG Yang1,2, WEI QingGuo1,2 & TANG XianChun1,2 1 Key Laboratory of Marginal Sea Geology, guangzhou Institute of Geochemistry, Chinese Academy of sciences, guangzhou 510640,{3. 2 Graduate university, Chinese Academy of sciences, Beijing 10003.,{3. 3.department of earth sciences, Nanjing university, Nanjing 210093.{3. Key Laboratory of Marginal Sea Geology Guangzhou Institute of GeochemistryChinese Academy of Sciences Guangzhou 510640 China

地关系与 petrographical 一起， petrological ，和 geochemicalcharacteristics ，和锆石人口，显示从在 Bangong-Nujiang 缝术地区的 Lagkor Lakeophiolite 的 plagiogranites (～ Gerze 县的 20 km 南方，中央西藏，中国)，由在海洋的外壳的运输期间的可锻的砍源于含水的斑粝岩的 anatexis 。因此，这种 plagiogranite 比传播海洋的外壳晚对或很少同时代。锆石虾 166 ±使 2.5 妈变老因为 plagiogranites 显示海洋的盆在中间的侏罗记在 Bangong-Nujiang 地区的西方的部分存在。

关键词：西藏改则县拉果错湖泊蛇绿岩斜长花岗岩锆SHRIMP U-Pb地质年代岩石成因

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Studies on the Preparation of Lanthanum-Copper Alloy by Molten Salt Electrolysis

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Journal of Rare earths 1991年第3期9卷 173-176页

作者： Tong Ye-Xiang Yang Qi-Qin Liu Guan-Kun Chen Qing-Song Zhou Xian-Zhi (department of Chemistry,zhongshan university,{3. 510275,china)

The electrochemical behaviour of copper electrode in molten NaCl-KCl-LaCl_3.has been *** La-Cu alloy is formed at first and then the metallic lanthanum is deposited when the La^(3.)is reduced on the copper *** technological conditions of preparing La-Cu alloy by consumable cathode have been dis- *** La-Cu alloy contained lanthanum over 90wt% was *** composition of alloy was LaCu_2 and *** current efficiency was 85% and the recovery of lanthanum was near 90%.

关键词： Lanthanum-copper alloy Molten salt Electrolysis Preparation

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Research on the dynamics of the South china Sea opening:Evidence from analogue modeling

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Science china earth sciences 2006年第10期49卷 1053-1069页

作者： SUN Zhen1,2, ZHOU Di1, ZHONG Zhihong3. XIA Bin2, QIU Xuelin1, ZENG Zuoxun4 & JIANG Jianqun5 1. CAS Key Laboratory of Marginal Sea Geology, South china Sea Institute of Oceanology, Chinese Academy of sciences, guangzhou 5103.1, china 2. CAS Key Laboratory of Marginal Sea Geology, guangzhou Institute of Geochemistry, Chinese Academy of sciences, guangzhou 510640, china 3. department of Technology, Shenzhen Branch of CNOOC, guangzhou 510240, china 4. Faculty of earth sciences, china university of Geosciences, Wuhan 43.074, china 5. Hainan Oil & Gas Exploration Company, Liaohe Oilfield Petrochina, Panjin 124010, china 1. CAS Key Laboratory of Marginal Sea Geology South China Sea Institute of Oceanology Chinese Academy of Sciences Guangzhou 510301 China 2. CAS Key Laboratory of Marginal Sea Geology Guangzhou Institute of Geochemistry Chinese Academy of Sciences Guangzhou 510640 China 3. department of Technology Shenzhen Branch of CNOOC Guangzhou 510240 China 4. Faculty of earth sciences China University of Geosciences Wuhan 430074 China 5. Hainan Oil & Gas Exploration Company Liaohe Oilfield PetroChina Panjin 124010 China

Independent of Indochina extrusion, the South china Sea experienced a process from passive continental rifting to marginal sea drifting. According to the fault patterns in the Beibu Gulf basin and the Pearl River Mouth basin, the continental rifting and early spreading stage from 3. to 26 Ma were controlled by extensional stress field, which shifted clockwise from southeastward to south southeastward. From 24 Ma on, the sea spread in NW-SE direction and ceased spreading at around 15.5 Ma. Integrated geological information with the assumption that the South china Sea developed along a pre-Cenozoic weakness zone, we did analogue experiments on the South china Sea evolu- tion. Experiments revealed that the pre-existing weakness zone goes roughly along the uplift zone between the present Zhu-1 and Zhu-2 depression. The pre-existing weakness zone is composed of three segments trending NNE, roughly EW and NEE, respectively. The early opening of the South china Sea is accompanied with roughly 15° clockwise rotation, while the SE sub-sea basin opened with SE extension. Tinjar fault was the western boundary of the Nansha block (Dangerous Ground), while Lupar fault was the eastern boundary of the Indochina, NW-trending rift belt known as Zengmu basin developed between above two faults due to block divergent of Indochina from Nansha. In the experiment, transtensional flower structures along NW-trending faults are seen, and slight inversion occurs along some NE-dipping faults. The existence of rigid massifs changed the orientations of some faults and rift belt, and also led to deformation concentrate around the massifs. The rifting and drifting of the South china Sea might be caused by slab pull from the proto South china Sea subducting toward Borneo and/or mantle flow caused by India-Asia collision.

关键词： South china Sea, rifting and drifting, clockwise rotation, analogue modeling, rigid massifs.

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Two new diterpenoids from the marine Soft coral Clavularia viridis

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Chinese Journal of Chemistry 1992年第2期10卷 155-160页

作者： SU,Jing-Yu ZHONG,Yong-Li ZENG,Long-Mei department of Chemistry,zhongshan university,{3. 510275 department of Chemistry Zhongshan University Guangzhou 510275

Two new dolabellane diterpenoids named clavudiol B(2)and clavirolide F(5),have been iso- lated from the soft coral Clavularia viridis,collected from Xisha Islands in the South china *** structures have been determined... 详细信息

关键词： Two new diterpenoids from the marine Soft coral Clavularia viridis ppm

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