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chinese Science Bulletin 2000年第11期45卷 1047-1052页

作者： GAO Jun, ZHANG Lifei & LIU Shengwei1. institute of geology, chinese academy of geological sciences, beijing 10003.,{4. 2. Department of geology, Peking University, beijing 100871, Chin institute of geology Chinese Academy of Geological Sciences Beijing China Department of geology Peking University Beijing China

The 4.Ar/39Ar ages indicate that the eclogite facies rocks of the Hasiate slice in the western Tianshan Mountains were formed at the early stage of Devonian （4.1 Ma） and had been uplifted to the greenschist facies tectonic level in the middle stage of Devonian （381 Ma）. The formation and uplift of the blueschists of the Akesayi slice are constrained to the late stage of Devonian （370-364.Ma）. The different tectonic slices in the high-pressure metamorphic belt have experienced the different uplift history.

关键词： western Tianshan Mountains eclogite blueschist 4.Ar/39Ar age.

CONVERGENCE AND SUPERCONVERGENCE OF HERMITE BICUBIC ELEMENT FOR EIGENVALUE PROBLEM OF THE BIHARMONIC EQUATION

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Journal of Computational Mathematics 2001年第2期19卷 139-142页

作者： Dong-sheng Wu (institute of Systems Science, academy of Mathematics and Systems sciences, chinese academy of sciences, beijing 100080, china ) 中科院系统科学所北京 100080

Provides information on a study which discussed the convergence and superconvergence for eigenvalue problem of the biharmonic equation using the Hermite bicubic element. Discussion on eigenvalue problem for biharmonic equation; Background on asymptotic error expansions and interpolation postprocessing; Superconvergence approximations to the eigenvalue and eigenfunction.

关键词： Hermite bicubic element biharmonic equation interpolation postprocessing eigenvalue problem

Seismic multi-arch structures in East china

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Science china Earth sciences 2006年第2期49卷 133-146页

作者： YANG Wencai1 & CHEN Zhide2 1.institute of geology, chinese academy of geological sciences, beijing 10003.,{4. 2.Daqing institute of Petroleum Exploration and Production, Daqing 163712,{4. institute of geology Chinese Academy of Geological Sciences Beijing China Daqing institute of Petroleum Exploration and Production Daqing China

In previous papers (Wencai, 2002, 2003), the author has analyzed the deep seismic reflection profiles along some of the Mesozoic plutons in East china, and has pointed out that the crustal structures around these intrusions usually correlate with a special seismic fabric called the seismic multi-arch structure. This paper will continue to show main characteristics of the seismic multi-arch structures and discuss their relationship with mantle-origin magmatism and the lithospheric thinning process. Calibration of seismic reflectors in chinese continental drilling sites shows that small-scale arch-like reflectors can be generated by fractured eclogites or other plutons, they do not belong to the multi-arch structure specially discussed in the paper. The multi-arch structure is char-acterized by several arch-like reflectors distributed in both the upper and lower crust with granitoid plutons or stocks exposed on the surface, which do not have obvious negative Europium anomalies. Based on the distribution pattern of arch reflectors, the multi-arch magmatic structures can be divided into three main types, namely the simple vertical combination type, the spread arch magmatic struc-ture and the arch-bouquet structure. All of them correlate to mantle-origin magmatism, but occur in different places. The spread arch magmatic structures occur within a Mesozoic/Cenozoic rift zone with very thin and hot lithosphere. The vertical combination type of the multi-arch structures occurred near the rift zones where lithosphere was thin and hot. The arch-bouquet magmatic structures occur far from the rift zones where the lithosphere is not hot. The continental rifting acted as the late episode of the lithospheric thinning process seeing that the rift zones usually coincide with the thinnest parts of the lithosphere in East china. In different locations within the lithospheric thinning areas, mantle-origin magmatic activities have different characteristics, which might generate different

关键词： deep seismic reflection, multi-arch structure, eclogite bodies, mantle-origin magmatism, East china.

Effects of cosmological constant on motion of UHECR particles

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Science china(Physics,Mechanics & Astronomy) 2005年第1期48卷 44-56页

作者： CHEN Shaoxia & CHANG Zhe institute of High Energy Physics, chinese academy of sciences,{4., china Graduate School of chinese academy of sciences,{4., china institute of High Energy Physics Chinese Academy of Sciences Beijing 100039 China Graduate School Chinese Academy of Sciences Beijing 100039 China

Recent astronomical observations manifest that about two-thirds of the whole energy in the Universe is contributed by a small positive cosmological constant A (> 0). Then, an asymptotically de Sitter spacetime is premised naturally. However, physics in the de Sitter spacetime is very different from that in the Minkowski spacetime. As the first step, a covariant formalism of the kinematics in the de Sitter spacetime is presented here. By solving exactly the equations of motion for a field, we obtain the dispersion relation of a free particle. It is noticed that the dispersion relation is dependent on the degree of freedom of angular momentum of the particle. We show the threshold anomaly of the ultra high energy cosmic ray disappears naturally in the framework of the de Sitter kinematics.

关键词： ultrahigh energy cosmic ray, cosmological constant, curved spacetime.

PREPARATION AND PROPERTIES OF ETHYL-CYANOETHYL CELLULOSE/POLYACRYLIC ACID COMPOSITE FILMS WITH REFLECTION COLORS

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chinese Journal of Polymer Science 2001年第3期19卷 277-282页

作者： Yong Huang institute of Chemistry, chinese academy of sciences, {4. 100080 china Laboratory of Cellulose and Lignocellulosics Chemistry Guangzhou institute of Chemistry chinese academy of sciences, Guangzhou 510650, china 中科院化学所北京

Ethyl-cyanoethyl cellulose [(E-CE)C]/acrylic acid (AA) becomes a cholesteric liquid crystalline solution withvivid colors when the (E-CE)C concentration is 4. wt%～52 wt%. (E-CE)C/polyacrylic acid (PAA) composites withcholesteric structure were prepared by polymerzing AA in (E-CE)C/AA liquid crystalline solutions. The layers of orderedpolymer chains in the cholesteric phase were inclined during polymerization and the degree of the inclination depended onthe polymerization temperature and the concentration of the solution before polymerization. The cholesteric structure in thecomposites could not be changed when temperature was lower than 100℃. Cross-linking of the PAA in compositesimproved their water-resistance. The cholesteric order of the composites without cross-linking was destroyed when theywhere immersed in water. The color derived from the selective reflection of the cholesteric phase of the cross-linkedcomposites turned from blue to red after the composites absorbed water. The color of the composites could be returned to theoriginal one when the absorbed water was removed from the swollen composites.

关键词： Cholesteric structure Composites Selective reflection Liquid crystalline solutions

Stability of proton and maximally symmetric minimal unification model for basic forces and building blocks of matter

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Science china(Physics,Mechanics & Astronomy) 2007年第3期50卷 303-310页

作者： WU YueLiang institute of Theoretical Physics, chinese academy of sciences, {4. 100080, china institute of Theoretical Physics Chinese Academy of Sciences Beijing China

With the hypothesis that all independent degrees of freedom of basic building blocks should be treated equally on the same footing and correlated by a possible maximal symmetry, we arrive at a 4.dimensional space-time unification model. In this model the basic building blocks are Majorana fermions in the spinor repre- sentation of 14.dimensional quantum space-time with a gauge symmetry GM4. = SO(1,3)×SU(32)×U(1)A×SU(3)F. The model leads to new physics including mirror particles of the standard model. It enables us to issue some fundamental questions that include: why our living space-time is 4.dimensional, why parity is not con- served in our world, how the stability of proton is, what the origin of CP violation is and what the dark matter can be.

关键词： gauge symmetry space-time symmetries beyond standard model and unification

Malanite——A New Cupric Platinum (Pt^(3+)) and Iridium (Ir^(3+)) Sulphide

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Acta Geologica Sinica(English Edition) 1997年第2期71卷 152-157,233页

作者： Yu Zuxiang institute of geology, chinese academy of geological sciences, beijing, {4. institute of geology Chinese Academy of Geological Sciences Beijing 100037 [?]Yu Zhuxiang Born in Nov. 1930 graduated from the Specialty of Petrology and Mineralogy of the Department of geology Beijing College of Geology in 1953. He has long engaged in the study of mineralogy as Research Professor at the Institute of Geology Chinese Academy of Geological Sciences.

Malanite was first found in veinlets of disseminated copper-nickel ores inZunhua County, Hebei Province, and then in platinum-bearing chromite ores in ShuangfengVillage, Yanshan. In the former case, malanite appears as octahedrons or dodecahedrons asso-ciated with pyrrhotite, pentlandite, sperrylite and cooperite; while in the latter case, it is massiveor present in anhedral glomerocrysts, filling in cracks of iridisite and associated with osmiride,ferrian platinum and iridisite. Malanite is steel-grey in colour, opaque with metallic lustre andblack streaks and brittle with no magnetism. H_M=5.0, VHN_(20)=4.7kg/mm^2, cleavage {111}sometimes observed. The calculated density is 7.57g/cm^3. The reflective colour is white with alight green tint. Internal reflections are not observed. This mineral is isotropic, showing nobireflection or reflection pleochroism in air. By means of electron microprobe analysis, the em-pirical formula (based on 7 atoms) is expressed as (Cu_(0.93)Fe_(0.06))_(∑0.99)(Pt_(1.03)Ir_(0.66)Rh_(0.04.Pd_(0.03)Co_(0.20)Ni_(0.03))_(1.99)S_(4.03) or (Cu_(0.95)Fe_(0.07))_(∑1.02)(Pt_(1.37)Ir_(0.4.)Co_(0.11)Rh_(0.08))_(∑2.01)S_(3.97). Five strongestlines (hkl, d, I) of X-ray powder diffraction data of malanite are 311,2.98(6); 4.0,2.4.(5);333, 1.90(7); 4.0, 1.75(10); 731, 1.29(5). It was known on the basis of X-ray powder diffractiondata that malanite is cubic, and the space group is Fd3m with α=0.994.nm, V=0.9821(3)nm^3 and Z=4. The type material of malanite is deposited at the geological Museum of china(GMC)s

关键词： new mineral malanite chrome ore

Relationship between Environmental Pollution of Coal Mine and Spectral Characteristics of Nearby Plants

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Journal of University of Science and Technology beijing 2001年第1期8卷 10-14页

作者： Liqing Lei institute of Geographic sciences and Natural Resources Research, chinese academy of sciences, beijing 100101, china Inst. of Geogr. Sci./Nat. Rsrc. Res. Chinese Academy of Sciences Beijing 100101 China

Remote sensing technology, as the most advanced method for collecting data, along with the common ways often used in the past on research of environmental science, was integrated to study the relationship between environmental pollution of coal mine and spectral characteristics of nearby plants. With compositive index and mean reflectivity at near infrared, a regression equation was established, and a conclusion was made that spectral reflectivity can be used to distinguish regions with different pollution degree. Through testing with real status of the research region, it is verified that this kind of integration and conclusion not only are helpful for human being in controlling the movement law of pollutants and the corresponding change of coal mine environmental quality but also bring a new way for the research of environment problems of coal mine.

关键词： remote sensing spectral characteristics reflectivity pollution index compositive index atmospheric pollution

^(14.C measurement of forest soils in Dinghushan Biosphere Reserve

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chinese Science Bulletin 1999年第3期44卷 251-256页

作者： SHEN Chengde , LIU Dongsheng (LIU Tungsheng) , PENG Shaolin, SUN Yanmin , JIANG Mantao , Yl Weixi , XING Changping , GAO Quanzhou , LI Zhi’an and ZHOU Guoyi Guangzhou institute of Geochemisry, chinese academy of sciences, Guangzhou 51064.,{4. institute of geology, chinese academy of sciences , beijing 100029,{4. South{4. institute of Botany, chinese academy of sciences, Guangzhou 510650,{4. Guannzhou institute of Geochemisry Chinese Academy of Sciences Guanazhou China institute of geology Chinese Academy of Sciences Beijing China South china institute of Botany Chinese Academy of Sciences Guangzhou China

Organic carbon in forest soils of Qingyunsi and Wukesong profiles can be divided into fast and slow components. Δ14. values of these profiles decrease with increasing of depth. The Δ14. values in 30—4. cm depth int... 详细信息

Organic carbon in forest soils of Qingyunsi and Wukesong profiles can be divided into fast and slow components. Δ14./sup>C values of these profiles decrease with increasing of depth. The Δ14./sup>C values in 30—4. cm depth interval of Wukesong profile are decreasing sharply until a very low value,showing that a strong geological environment change occurred about 1 560 years ago. The 14./sup>C apparent ages of Wukesong profile show that the coniferous and broad-leaf mixed forests around Wukesong profile have been developing since 4.5 a BP, which is consistent with historical documents. The penetrating depths of "bomb 14./sup>C" in Qingyunsi and Wukesong profiles are 10 and 20 cm, respectively.

关键词： Dinghushan forest soil 14. tracing 14. apparent age.

Recent advances in the data analysis method of functional magnetic resonance imaging and its applications in neuroimaging

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Progress in Natural Science:Materials International 2006年第8期16卷 785-795页

作者： TIAN Jie, YANG Lei and HU Jin (institute of Automation, chinese academy of sciences, {4. 100080, china Graduate School of chinese academy of sciences, beijing 10003., china) institute of Automation Chinese Academy of Sciences Beijing 100080 China Graduate School of chinese academy of sciences Beijing 100039 China

Functional magnetic resonance imaging (fMRI) has opened a new area to explore the human brain. The fMRI can reveal the deep insights of spatial and temporal changes underlying a broad range of brain function, such as motor, vision, memory and emotion, all of which are helpful in the clinical investigation. In this paper, we introduce some recent-developed algorithms for fMRI signal detection such as model-driven method (general linear model, deconvolution model, non-linear model, etc. ) and data-driven method (principle component analysis, independent component analysis, self-organization mapping, clustered constrained non-negative matrix factorization, etc. ). We also propose several important applications of neuroimaging and point out their shortcomings and future perspectives.

关键词： fMR1 data analysis neuroimaging.