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Journal of Systems Engineering and Electronics 1990年第1期1卷 32-36,47页

作者： Chen Jingxiong(beijing institute of Radio Measurement, beijing.{3.) beijing institute of Radio Measurement Beijing China

In this paper a method of eigenfunction expansion associated with 2nd order differential equation is developed by using the concept of theory of distribution. An application of the method to the infinite long antenna ... 详细信息

关键词： Eigenfunction expansion lnfinite domain.

ADVANCE IN Ti_3.Al AND TiAl INTERMETALLICS RESEARCH IN CISRI

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Acta Metallurgica Sinica(English Letters) 1995年第Z1期8卷 531-541页

作者： ZHONG Zengyong ZO U Dunxu LI Shiqiong (Central Iron and Steel Research institute, beijing 100081 . china) Central and Steel Research Inst Beijing China

Recent work on Ti_3.l base alloy,TAC-1, developed in CISRI, including investigations of effects of modification in alloying and TMP on microstructural characteristics and mechanical behaviour,indicates that alloy TAC -1 is very promising structural material for a number of elevated temperature applications. Stuody dealing with a reverse relation between RT ductility and toughness found on TiA base alloy, TAC-2, led to development of a special heat treatment technique for producing a fine filly lamellar microstructure (FFL), which gives a high and balancing ductility and toughness. This is also of significance for promoting engineering applications of this alloy.

关键词： Ti_3.l TiAl intermetallics

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羌塘盆地构造单元划分及含油气远景评价

同济大学学报（自然科学版） 2002年第12期30卷 1462-1467页

作者：杨辉王永涛姚政道吕金海石油大学CNPC物探重大实验室中国石油集团地球物理勘探局河北涿州072751

对 14条近 40 0 0km的大地电磁测深资料进行了一维及二维连续介质反演 .根据反演结果及地面地质资料解释确定了侏罗系、上三叠统底界面海拔高度图以及前泥盆系顶界面海拔高度图。

关键词：羌塘盆地构造单元划分含油气远景评价大地电磁测探

Possibility of Reducing Formations of NO_x and SO_2 Simultaneously during Coal Combustion

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International Journal of Minerals,Metallurgy and Materials 2000年第3期14卷 165-169页

作者： Chunbao Xu, Shengli Wu, Daqiang Cang ( Metallurgy School, University of Science and Technology beijing, beijing 100083. china {3. for Chemical Reaction Science, Tohoku University, Japan) Metallurgy School University of Science and Technology Beijing Beijing 100083 China institute for Chemical Reaction Science Tohoku University Japan

Comparing with other NO_x and SO_2 control technologies, in-bed reducing NO_x and SO_2 simultaneously during coal combustion may lower the investment and operation cost. However, there are several possible contradictions between the reduction of NO_x and the capture of SO2 during combustion: 1) CO rich atmosphere is favorable for the reduction of NO_x, whereas O_2 rich favorable for the capture of SO_2; 2) higher preheating temperature of coal is favorable for reducing NO_x, but unfavorable for reducing SO_2; 3. sulphation of some minerals may deactivate their catalytic effect on the reduction of NO_x. The attempts to eliminate such contradictions by coating coal granules with thin layer of monometallic oxides and mixed oxides were proposed. Ni_2O_3.and Fe_2O_3.showed high activity on NOx reduction and CaO and Cr_2O_3.showed good effect on sulfur capture. The mixed metallic oxides, e.g., Fe_2O_3.iO, etc., showed effective for both NO_x reduction and SO_2 retention. It is possible to in-bed reduce NO_x and SO_2 simultaneously if the adhering materials are properly chosen to be difunctional materials of both active catalysts for NO_x reduction reactions and better sorbents for SO_2 retention.

关键词： coal combustion purification of NO and SO catalyst sorbent

Mafic and felsic magma interaction during the construction of high-K calc-alkaline plutons within a metacratonic passive margin:The Early Permian Guyang batholith from the northern North china Craton

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Mafic and felsic magma interaction during the construction o...

Farming and forestry land use changes in china and their driving forces from 1900 to 1980

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： Xiaohui Zhang~(a,*),Qian Mao~a,Hongfu Zhang~a,Mingguo Zhai~a,Yueheng Yang~a,Zhaochu Hu~b a State Key Laboratory of Lithospheric Evolution,institute of geology and geophysics,{3. academy of Sciences,beijing 100029,china b State Key Laboratory of Geological Processes and Mineral Resources,china University of Geoscience,Wuhan 43.074,china

Zircon U-Pb and hornblende Ar/Ar dating document an Early Permian emplacement time for the Hercynian Guyang batholith from the northern margin of the North china Craton(NCC),with a variety of lithologies including:gabbro-gabbroic diorite-leuconorite,diorite and granodiorite,microgranular magmatic enclaves(MME),mafic dyke and *** relations,petrological,elemental,whole-rock Sr-Nd and zircon Hf isotopic data show that(1) the gabbros and gabbroic diorites exhibit strong enrichment of large ion lithophile element(LILE) and lightrare earth element(LREE),depletion in high field strength element(HFSE), and have moderately enriched isotopic compositions with Sr/Sr ranging from 0.7050 to 0.7053.ε(t) from - 8.08 to - 10.2 and zirconε(t) from - 6.7 to - 12.0;while the leuconorites are characterized by low REE contents,conspicuous positive Eu anomaly and comparable Sr-Nd compositions to gabbroic *** features suggest that they may represent complementary products from a parental magma derived from a subduction-related metasomatized sub-continental lithospheric mantle(SCLM) source;(2) the monzogranites range from 74.3.to 75.6%SiO,with high Sr-Ba abundances and elevated Sr/Y and La/Yb *** high-silica adakitic affinity,plus their indistinguishable isotopic compositions from the mafic ones(Sr/ Sr = 0.7053.to 0.7055,ε(t) = - 10.5 to - 11.3.zirconε(t) = -8.5 to -11.8),indicates a felsic parental magma from partial melting of mixed protoliths composed of newly underplated mafic lower crustal and ancient mafic lower crustal materials;(3. the diorites and granodiorites contain abundant MME and display various scales of petrologic textures indicative of magma *** also have intermediate geochemical compositions between gabbroic diorite and *** with their evolved isotopic compositions(Sr/ Sr = 0.7050 to 0.7064,ε(t) = -8.3. to -13.9,zirconε(t) = - 7.9 to -15.5),they are inferred to be formed by mixing between SCLM-derived mafic magma and cru

关键词： Early Permian Magma mixing High-K calc-alkaline batholith Post-collisional Metacraton North china Craton

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Science china Earth Sciences 2005年第10期 181-191页

作者： GE Quansheng & DAI Junhu institute of Geographic Sciences and Natural Resources Research, chinese academy of Sciences, {3. 100101, china

A variety of agricultural and forestry land use materials, especially those in the first half of 20th century, were collected. According to land use change in this period, the whole country is demarcated into seven regions, Northeast china, North china, Northwest and Loess Plateau, Southeast and Coastal Region, Southwest china, Qinghai-Tibetan Plateau, Inner Mongolia and Xinjiang, in proper order by using Cluster Analysis. The farming and forestry land use change in these regions were analyzed. The results show that the total cultivated land areas increased in this period, especially in the 1950s and 1960s the cultivated land area increased more significantly, but differed in different regions, and the most rapid increasing rate was 2.63.percent a year. On the other hand, the forestry land area was increasing in most parts of this period, especially after 1949. But in most regions, the decrease of forestry land area at the end of 1970s is also very obvious. It is regarded that the population increase, food production, natural disasters and some related government policies were among the main driving factors for farming and forestry land use change.

关键词： land use change cultivated land forestry land driving factors 20th century.

A note on the derivation of the derivatives of invariants of stretch tensor to the right Cauchy-Green tensor

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Progress in Natural Science:Materials International 2006年第1期16卷 96-99页

作者： TIAN Dongyan, JIN Ming and DUI Guansuo (institute of Engineering Mechanics, School of Civil Engineering and Architecture, beijing Jiaotong University, beijing 100044,{3.) [a]beijing Jiaotong University Institute of Engineering Mechanics School of Civil Engineering and Archtecture Beijing China

A new approach for the derivation of the principal invariants of the stretch tensor with respect to the right Cauchy- Green tensor is presented in this paper. According to the definition of the derivation of tensor function, the three first-order derivatives for the principal invariants of the stretch tensor are obtained through derivation directly to the right Cauchy-Green tensor by incremental method. Then the three second-order derivatives are yielded by the derivation to the right Cauchy-Green strain tensor directly. Furthermore, an explicit expression of the tangent modulus of the general Varga material is given as an example.

关键词： continuum mechanics invariant strain energy tangent modulus.

Correlation of Dust Storms in china with Chlorophyll a Concentration in the Yellow Sea between 1997-2007

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Atmospheric and Oceanic Science Letters 2012年第2期5卷 140-144页

作者： TAN Sai-Chun 1,2 and SHI Guang-Yu 1 1 State Key Laboratory of Numerical Modeling for Atmospheric Sciences and Geophysical Fluid Dynamics,institute of Atmospheric Physics,chinese academy of Sciences,{3. 100029,china 2 Key Laboratory of Meteorological Disaster of Ministry of Education,Nanjing University of Information Science and Technology,Nanjing 210044,china [a] State Key Laboratory of Numerical Modeling for Atmospheric Sciences and Geophysical Fluid Dynamics Institute of Atmospheric Physics Chinese Academy of Sciences Beijing 100029 China[b] Key Laboratory of Meteorological Disaster of Ministry of Education Nanjing University of Information Science and Technology Nanjing 210044 China

Based on daily observation data at 222 meteorological stations in china,the characteristics of dust storms between 1997 and 2007 were ***,the relationship between dust events and chlorophyll (Chl) a concentration in the Yellow Sea was *** were six regions with high annual frequencies of dust *** seasonal distribution of dust storms showed spatiotemporal *** six regions with highest annual frequencies also exhibited high frequencies of dust storms in *** storms in most regions occurred in *** all dust storms in china,sixty-five percent of all dust storms occurred during the *** area and frequency of dust storms were smaller in fall and winter than in spring and summer.A significant correlation was found between dust events and Chl a concentration in the Yellow *** correlation regions included Qinghai-Xizang region,part of the Hexi Corridor,the western Inner Mongolia and Hetao Regions,and the Hunshandake *** high correlation may be induced by the high ratio of dust storms in the abovementioned regions that arrive over the Yellow Sea,as inferred through a forward trajectory analysis;especially notable is dust transported at a lower altitude (3.km).

关键词： dust storm spatial distribution seasonal variation chlorophyll Yellow Sea

INVESTIGATION ON 1/3.111] FRANK LEDGE DISLOCATIONS ATα_2/γINTERFACE IN HOT-DEFORMED Ti-45Al-10Nb ALLOY

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Acta Metallurgica Sinica(English Letters) 1997年第4期10卷 323-328页

作者： J.G WanG L.C Zhang G.L. Chenand HQ. Ye(State Key Laboratory for Advanced Metals and Materials, Unborsity of Science and Technology beijing,beijing 100083. china)(Laboratory of Atond Imaging of Solids, {3. of Metal Research, chinese academy of Scienc Univ of Science and Technology Beijing Beijing China

The dislocation ledges at the α2/7 intedece in a hot-dejormed Ti-45Al-10N alloywere analyzed by high-resolution tmnsmission electron microscopy. A new type ofdislocation ledge containing 1/3.111] Frank partial was found. The height of the ledgestDas always three [111]γplanes. The Burpers vectore of these diBlocation ledges weredetermined to be 1/2[110] and 1/23. *** partials at noral ledges, i.e. 90 dep. ShockIey Partial dislocation +1/3.111]Frank partial dislocation; and 3. deg. Shockley partial dislocation + 1/3.111] Frankparfial dislocations. The jormation mechanism of this new tare of dislocation ledgewas discussed.

关键词： titanium aluminide thermomechanical treatment phase interface tmnsmission electron microscopy

Non-metallic Inclusions in Continuously Cast Aluminum Killed Steels

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International Journal of Minerals,Metallurgy and Materials 2000年第3期14卷 193-196页

作者： Wenjun Wang, Xinhua Wang, Jiongming Zhang, Wanjun Wang, Youyu Zhou ( Metallurgy School, University of Science and Technology beijing, beijing 100083. china Steelmaking Research {3., Wuhan Iron and Steel Group, Wuhan 43.080, china) Metallurgy School University of Science and Technology Beijing Beijing 100083 China Steelmaking Research institute Wuhan Iron and Steel Group Wuhan 430080 China

In aluminum killed steels, the size, shape, quantity and formation of non-metallic inclusions in ladle steel (before and after RH vacuum treatment) and in tundish as well as in slabs were studied by EPMA (Electron Probe Microanalysis) and by analyzing the total oxygen. The results showed that in the slabs the total oxygen was quite low and the inclusions discovered were mainly small-sized angular alumina inclusions. This indicates that most inclusions have been removed by floating out during the continuous casting process. In addition, the countermeasures were discussed to decrease the alumina inclusions in the slabs further.

关键词： aluminum killed steel non-metallic inclusion alumina continuous casting