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Vertical quantitative and dominant population distribution of the bacteria isolated from the Muztagata ice core

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Science China Earth Sciences 2005年第10期48卷 1728-1739页

作者： XIANG Shurong1, YAO Tandong1, 2. AN Lizhe1, 3. WU Guangjian2. XU Baiqing2. MA Xiaojun 3. LI Zhen1, WANG Junxia1 & YU Wusheng1 1. Key Laboratory of Ice Core and Cold Regions Environment, Cold and Arid Regions Environmental and Engineering Research Institute, Chinese Academy of Sciences, Lanzhou 73.000, China 2. Institute of Tibetan Plateau Research, Chinese Academy of Sciences, beijing 100085, China 3. College of Life Science, Lanzhou University, Lanzhou 73.000, China Key Laboratory of Ice Core and Cold Regions Environment Cold and Arid Regions Environmental and Engineering Research Institute Chinese Academy of Sciences Lanzhou China Institute of Tibetan Plateau Research Chinese Academy of Sciences beijing China College of Life Science Lanzhou University Lanzhou China

Vertical distribution of the main bacteria isolated from the Muztagata ice core (about 2..4 m) was investigated by means of cultivation and 16S rRNA sequence analysis. The results showed that the amount of culturable bacteria fluctuated with ice core depth, and was more in dirty layer than in clean ice, which suggested the close corresponding relationship between high input of the bacteria deposited by wind and snowflow and dirty layer. Most of the bacteria were psychrophiles and psychrotolerants, including α- and γ-proteobacteria, Cryobacterium psychro-philum, CFB (Cytophaga-Flavobacterium-Bacteroides) group, high-G+C gram-positive bacteria (HGC). Acinetobacter sp. and HGC repeatly occurred in different ice depths, and their quantita-tive distribution was consistent with the change of the total amount of culturable bacteria with depth, which suggested the main bio-indicator; while Flavobacterium, Cryobacterium psychro-philum, and α-proteobacteria, also functioned as a secondary indicator of climatic and environ-mental changes. This study is the first report concerning continuous quantitative variation and pattern of the main culturable bacteria in ice core section.

关键词： Pamirs Plateau, ice core, pattern of bacteria, bio-indicator.

Mineralogy and crystal structure determination of Mg-fillowite

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Science China Earth Sciences 2005年第5期48卷 635-646页

作者： MA Zhesheng 1 , SHI Nicheng 1 & YE Danian 2.1. China University of Geosciences, beijing 100083. China 2. Institute of Geology, Chinese Academy of Sciences, beijing 10002., China 1. China University of Geosciences 100083 Beijing China 2. Institute of Geology Chinese Academy of Sciences 100029 Beijing China

Accurate crystal structure determination of complex phosphate Mg-fillowite ? Na2.a(Mn4Mg2.e)7[PO4]6 has been finished. Mg-fillowite occurs in muscovite-pegmatite in the Altay area, Xinjiang, China. It is of the trigonal lattice, with space group R-3. unit cell a=1.5143.3. nm, c=4.3.91(2. nm, V=8.573. nm3. Z = 18. The R-factor of the determination accuracy is R (I > 2. ( I )) = 0.0776. The cationic polyhedra consist of two kinds of structural units: compound col- umn and screw column. In three-dimensional space, they are linked with each other through corner sharing or edge sharing to build the entire structure. There are 45 atoms in an asymmetric unit and 72. atoms in a unit cell. In terms of types and connection manners of the coordination polyhedra, the degree of complicity is rarely seen in all mineral crystal structures. Study of such a structure is significant for the classification of phosphate and the building rule of coordination polyhedra in a complex crystal structure.

关键词： Mg-fillowite, complex phosphate, crystal structure, coordination polyhedron.

In situ reproductive organs of Early Cretaceous ferns from northeast China

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Chinese Science Bulletin 1997年第23期42卷 1977-1980,2026页

作者： DENG Shenghui and CHEN Fen1. Research Institute of Petroleum and Development, beijing 100083.2. China University of Geosciences, beijing 100083. China Research Institute of Petroleum and Development Beijing China University of Geosciences Beijing China

FILICOPSIDA is a predominant group of the Early Cretaceous floras of northeast China, whichapproximates 100 species and accounts for more than one third of the floras. The majority ofthis group are of great importance and significance in stratigraphy. The previous studies ofthese ferns are mainly morphological, with only a few concerning the in situ spores andsporangia. In recent years. the authors have carried out a research project on the in situreproductive organs of the Early Cretaceous ferns from/ basins of Inner Mongolia, Liaoning,Jilin and Heilongjiang of northeast China. The study focuses on 3. species of 17 genera be-longing to 10 families. The present note briefly introduces the results of this study by listingsome representative species.

关键词： northeast China Early Cretaceous Filicopsida in situ reproductive organs.

Simulation of Thermodynamics and Kinetics for KR Desulphurization

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Journal of Iron and Steel Research International 2011年第S2期18卷 98-106页

作者： XU An-jun1, ZHANG Mao-lin2. ZHANG Hui-ning1, LI An-dong3.(1. School of Metallurgical and Ecological Engineering, University of Science and Technology beijing, beijing 100083.China 2. Steel-Making and Continuous Casting Engineering Institute, Capital Engineering and Research Incorporation Limited, beijing 100176,China 3. Stainless Steel Company, Baosteel group, Shanghai 2.1900,China) Univ Sci & Technol beijing Sch Met & Ecol Engn Beijing 100083 Peoples R China Capital Engn & Res Inc Ltd Steel Making & Continuous Casting Engn Inst Beijing 100176 Peoples R China Stainless Steel Co Baosteel Grp Shanghai 201900 Peoples R China

This paper seeks to optimize parameters, reduce the cost of desulphurization and the consumption of operation about KR pretreatment of hot metal at the Stainless Steel Company, Baosteel group. Based on the theoretical analysis of physical chemistry in metallurgy, simulation experiments of the KR desulphurization of hot metal were conducted in a laboratory and the composition of the desulphurization was optimized, by means of chemical analysis, DSC, SEM and EDS. The water modeling displays the fluid flow characteristics of KR desulphurization. Combination of the techniques and production at the Stainless Steel Company, Baosteel group, the optimized parameters of the process are put forward.

关键词： desulphurization of hot metal KR, desulphurization thermodynamics water model

Corrosion and electrochemical behavior of as-cast Mg-5Y-7Gd-1Nd-0.5Zr magnesium alloys in 5%NaCl aqueous solution

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Progress in Natural Science:Materials International 2011年第4期21卷 314-321页

作者： Xin ZHANG~(1,2.3.,Kui ZHANG~1,Xing-gang LI~1,Cong WANG~4,Hong-wei LI~(2.3.,Chang-shun WANG~(2.3.,Xia DENG~1 1.State Key Laboratory for Fabrication and Processing of Nonferrous Metals, beijing General Research Institute for Nonferrous Metals,beijing 100088,China 2.beijing Engineering Research Center for Advanced Manufacturing and Evaluation of Special Vehicle Parts,beijing 100072.China 3.Institute of Technology,beijing north Vehicle group corporation,beijing 100072.China 4.Fengtai Military Representative Office,beijing Military Representative Office,PLA,beijing 100072.China [a] State Key Laboratory for Fabrication and Processing of Nonferrous Metals Beijing General Research Institute for Nonferrous Metals Beijing 100088 China [b] beijing Engineering Research Center for Advanced Manufacturing and Evaluation of Special Vehicle Parts Beijing 100072 China [c] Institute of Technology Beijing North Vehicle Group Corporation Beijing 100072 China [d] Fengtai Military Representative Office Beijing Military Representative Office PLA Beijing 100072 China

The corrosion mechanism of the as-cast Mg-5Y-7Gd-1Nd-0.5Zr magnesium alloy immersed in 5%NaCl aqueous solution was investigated by electrochemical test and *** electrochemical results indicate that the corrosion resistance of Mg-5Y-7Gd-1Nd-0.5Zr alloy in 5%NaCl aqueous solution gradually deteriorates with immersion time increasing from 2.h,2. h,60 h,to 108 h,which is consistent with the SEM observation of corrosion *** Cl-anion leads to the initiation and development of the corrosion pits,and Mg-5Y-7Gd-1Nd-0.5Zr alloy exhibits filiform type of attack under significant anodic control of magnesium solution *** corrosion potential becomes noble with increasing immersion time.

关键词： magnesium alloys Mg-5Y-7Gd-1Nd-0.5Zr corrosion electrochemical behavior

Electroluminescent properties of three ternary europium complexes with different phenanthroline derivatives

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Science China Chemistry 2004年第4期47卷 326-334页

作者： BIAN Zuqiang1,2. GAO Deqing1, GUAN Min1, XIN Hao1, LI Fuyou1, HUANG Chunhui1, WANG Kezhi2.& JIN Linpei2.1. State Key Laboratory of Rare Earth Materials Chemistry and Applications, Peking University, beijing 100871, China 2. Department of Chemistry, beijing Normal University, beijing 100875, China 1. State Key Laboratory of Rare Earth Materials Chemistry and Applications Peking University 100871 Beijing China 2. Department of Chemistry Beijing Normal University 100875 Beijing China

Three ternary Eu(III) complexes with general formula of Eu(DBM)3.N (DBM = dibenzoylmethanate, and LN (N = 1-3.) stand for three different 1,10-phenanthroline derivatives) have been synthesized for vacuum deposition films-based electroluminescent devices. The complex Eu(DBM)3.3.(L3.= 2.phenyl-3.[3.(carbazol-9-yl)propyl]imidazo[4,5-f]1,10-phenan-throline) was designed with an effort to combine the electron-transporting phenanthroline platform and the hole-transporting carbazole group into one molecule expecting to improve both electron and hole transporting properties simultaneously. The results show that the variation of the neutral ligands in Eu(III) mixed ligand complexes is a simple and effective approach to the improvement in the thermal stability, PL and EL properties of materials. A double-layer device with the configuration of ITO/TPD (50 nm)/Eu(DBM)3.3.(50 nm)/Mg0.9Ag0.1 (2.0 nm)/Ag (100 nm) exhibited Eu(III)-based pure red emission with a maximum brightness of 561 cd/m2.at 16 V, and an onset driving voltage of 8 V. A device with the configuration of ITO/TPD (50 nm)/[Eu(DBM)3.3.(5 nm):BCP (5 nm)]4/BCP (2. nm)/AIQ (10 nm) Mg0.9Ag0.9 (110 nm)/Ag (100 nm) gave high efficient and pure red light emission with a luminance of 1419 cd/m2. Keywords dibenzoylmethane - electroluminescence - lanthanide - N ligands

关键词： dibenzoylmethane electroluminescence lanthanide N ligands

Similar component analysis

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Progress in Natural Science:Materials International 2006年第12期16卷 1343-1347页

作者： ZHANG Hong~1**, WANG Xin~1, LI Junwei~2.and CAO Xianguang~1(1. Image Center, Astronautics School, BeiHang University, beijing 100083. China 2. The 2.7th Institute of the Second Academy of China Aerospace Science Industry {2., beijing 100854, China) [a]Image Center Astronautics School BeiHang University Beijing China [b]The 2.7th Institute of the Second Academy of China Aerospace Science Industry corporation Beijing China

A new unsupervised feature extraction method called similar component analysis (SCA) is proposed in this paper. SCA method has a self-aggregation property that the data objects will move towards each other to form clusters through SCA theoretically, which can reveal the inherent pattern of similarity hidden in the dataset. The inputs of SCA are just the pairwise similarities of the dataset, which makes it easier for time series analysis due to the variable length of the time series. Our experimental results on many problems have verified the effectiveness of SCA on some engineering application.

关键词： clustering feature extraction similar component.

Wave tectono-sedimentary processes in Tarim basin

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Science China Earth Sciences 2005年第11期48卷 1949-1959页

作者： JIN Zhijun1,2. ZHANG Yiwei1 & CHEN Shuping1 1. Key Laboratory for Hydrocarbon Accumulation, Ministry of Education, China University of Petroleum, beijing 102.49, China 2. Exploration and Production Research Institute, China Petroleum & Chemical corporation, beijing 100083. China 1. Key Laboratory for Hydrocarbon Accumulation Ministry of Education China University of Petroleum 102249 Beijing China 2. Exploration and Production Research Institute China Petroleum & Chemical Corporation 100083 Beijing China

Based on the unconformities, the formation times of structures, and geological wave filtering applied to basin fills of typical wells around the Manjiaer area in the Tarim basin, the wave tectono-sedimentary processes in the Tarim Basin are discussed. The results of geological wave filtering of basin fills of typical wells show that, in time domain, the evolution of the Tarim basin was controlled by various wave processes with the periods of 740±Ma, 2.0±Ma, 100±Ma and 3.±Ma. The analyses of basin fills, basin subsidence and unconformities show that the trends of the sedimentary facies belts, depocenters, and centers of subsidence migrated and interchanged periodically with periods of 2.0±Ma. These show the propagation of wave movements in space domain. The wave evolution of the Tarim basin is of significance to understanding the formation of the oil and gas reservoirs in the basin.

关键词： Tarim basin, tectonics, sedimentation, crustal undation, wave evolution

The precipitation and effect of nano nitrides in HSLC steel

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Science China(Technological Sciences) 2008年第7期51卷 989-998页

作者： FU Jie1, LIU YangChun1,2.& WU HuaJie1,3.1 School of Metallurgical and Ecological Engineering, University of Science and Technology beijing, beijing 100083. China 2.Shougang Technology Research Institute, Shougang (group) {3., beijing 100041, China 3.Metallurgical Engineering Research Institute, University of Science and Technology beijing, beijing 100083. China 1. School of Metallurgical and Ecological Engineering University of Science and Technology Beijing Beijing 100083 China 2. Shougang Technology Research Institute Shougang (Group) Corporation Beijing 100041 China 3. Metallurgical Engineering Research Institute University of Science and Technology Beijing Beijing 100083 China

The existing forms of N and Al in HSLC (high strength low carbon) steel produced by TSCR (thin slab casting and rolling process), the precipitation thermodynamics and kinetics of AlN, and its effects on structure and mechanical property are studied. The experimental results show that only a small quantity of nitrogen is com- bined into AlN in HSLC steel produced by TSCR and most of the nitrogen in steel is still free nitrogen. Aluminum-nitride is mainly precipitated during the period of slow air cooling after coiling, but not during rolling and water cooling. The acid-soluble aluminum has no obvious effect on the grain size and mechanical property of HSLC steel produced by TSCR whose acid-soluble aluminum content is 0.005%―0.043.. The precipitation of AlN is not the main cause of grain refinement of HSLC steel produced by TSCR, nor is AlN the dominating precipitate that has precipitation strengthening effect. The nano nitrides are not pure AlN, but have complex compositions.

关键词： thin slab casting and rolling high strength low carbon steel AlN nano nitride precipitation strengthening