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Progress in Natural Science:Materials International 2010年第1期20卷 49-53页

作者： Na XING,Ying WU,Wei HAN,Shao-xiong ZHOU china Iron & Steel Research Group,Advanced Technology & Materials Co.,ltd.,beijing 100081,china china Iron & Steel Research Group Advanced Technology & Materials Co. Ltd. Beijing 100081 China

The as-cast Mg-10Ni-2Mm(mole fraction,%)alloy was prepared by a simple and low-cost two-step method of pre-alloying and vacuum induction *** nanocrystalline alloy was obtained by the melt-spun process with the surface velocity of copper wheel of 10.5 m/*** hydrogen storage properties were examined by PCT *** enthalpy(ΔH)and entropy(ΔS)of the alloy determined by van’t Hoff plots indicate that the thermodynamic performance of the nanocrystalline alloy is improved by fast diffusion ability of hydrogen in the nanocrystalline microstructure embedding nano-particles of intermetallics compounds Mg2Ni and *** reaction kinetics of the melt-spun alloy is greatly improved due to short diffusion path of hydrogen in the nanocrystalline microstructure,resulting in better overall hydrogen storage *** hydrogen storage capacity is 5.09%(mass fraction,hereinafter the same),and the amount of hydrogen desorption is 4.86%.The hydrogen desorption rate of 95.5%in the alloy is available.

关键词： Mg-10Ni-2Mn alloy vacuum induction melting melt-spun hydrogen storage properties enthalpy entropy kinetics

Microorganisms desulfurization of coal

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Journal of Environmental Sciences 1993年第1期5卷 83-89页

作者： Zhong Huifang and Li YaqinInstitute of Microbiology, Chinese Academy of Sciences, beijing 100080, china

A culture of Thiobacillus ferrooxidans strain T-4, isolated from Song Zao Coal Mining, china, is able to use pyrite from coal as a source of energy. The bacterial culture solution with 108 -109 cells/ml, pH 1.55 - 1.70 was employed in the nine coal samples with -200 mesh have been studied at initial pH 1.7.30℃ , 20-30% coal pulp density. The bacterial removal sulfur from coal in samples 3, 4, 6 and 7 were reduced to 1.05 - 1.33% and 86.11% of pyritic sulfur can be removed in 4-24 hours.

关键词： Thiobacillus ferrooxidans microorganisms desulfurization.

Special relativity and theory of gravity via maximum symmetry and localization

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Science china Mathematics 2008年第4期51卷 568-603页

作者： GUO HanYing Institute of Theoretical Physics Chinese Academy of Sciences beijing 100080 china Institute of Theoretical Physics Chinese Academy of Sciences Beijing China

Like Euclid, Riemann and Lobachevski geometries are on an almost equal footing, based on the principle of relativity of maximum symmetry proposed by Professor Lu Qikeng and the postulate on invariant universal constants c and R, the de Sitter/anti-de Sitter (dS/AdS) special relativity on dS/AdS-space with radius R can be set up on an almost equal footing with Einstein’s special relativity on the Minkowski-space in the case of R→∞.Thus the dS-space is coin-like: a law of inertia in Beltrami atlas with Beltrami time simultaneity for the principle of relativity on one side, and the proper-time simultaneity and a Robertson-Walker-like dS-space with entropy and an accelerated expanding S 3 fitting the cosmological principle on another side.If our universe is asymptotic to the Robertson-Walker-like dS-space of R ? (3/Λ)1/2, it should be slightly closed in O(Λ) with entropy bound S ? 3πc 3 k B /ΛG?. Contrarily, via its asymptotic behavior, it can fix on Beltrami inertial frames without ‘an argument in a circle’ and acts as the origin of inertia.There is a triality of conformal extensions of three kinds of special relativity and their null physics on the projective boundary of a 5-d AdS-space, a null cone modulo projective equivalence [ $ \mathcal{N} $ ] ? ? P (AdS 5). Thus there should be a dS-space on the boundary of S 5 × AdS 5 as a vacuum of supergravity.In the light of Einstein’s ‘Galilean regions’, gravity should be based on the localized principle of relativity of full maximum symmetry with a gauge-like dynamics. Thus, this may lead to the theory of gravity of corresponding local symmetry. A simple model of dS-gravity characterized by a dimensionless constant g ?(ΛG?/3c 3)1/2 ～ 10?61 shows the features on umbilical manifolds of local dS-invariance. Some gravitational effects out of general relativity may play a role as dark matter.The dark universe and its asymptotic behavior may already indicate that the dS special relativity and dS-gravity be the foundati

关键词： special relativity de Sitter invariance gravity local de Sitter invariance umbilical manifold 83A05 83D05 53A35 53B50

The Greatest Prime Factor of the Integers in a Short Interval (Ⅳ)

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Acta Mathematica Sinica,English Series 1996年第4期12卷 433-445页

作者： Jia Chaohua Institute of Mathematics Academia Sinica beijing, 100080 china Institute of Mathematics Academia Sinica Beijing China

Let P（x） denote the greatest prime factor of ∏x1/2n. In this paper, we shall prove that P（x）>x0.728holds true for sufficiently large x.

关键词： Math In The Greatest Prime Factor of the Integers in a Short Interval

Some Applications of Projection Operators in Wavelets

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Acta Mathematica Sinica,English Series 1995年第1期11卷 105-112页

作者： Han Bin Institute of Mathematics Academia Sinica beijing,100080 china Academia Sinica

By rewriting the projection operator P0 in wavelets in another formula,we obtain a characterization of dim JV0（x）where V0 is a Γ-shift-invariant subspace of L2（Rn）derived from a dual wavelet basis and prove that there does not exist a wavelet function ψ ∈ L2（R）such that （?）has compact support and ∪k∈ZZ（supp■+4πk）=R up to a zero subset of R.

关键词： Some Applications of Projection Operators in Wavelets

DYNAMICS IN NEWTONIAN-RIEMANNIAN SPACETIME (Ⅰ)

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Applied Mathematics and Mechanics(English Edition) 2000年第7期21卷 825-835页

作者： Zhang Rongye (Institute of Mathematics, Academia Sinica, beijing 100080, P R china) Institute of Mathematics Academia Sinica Beijing P R China

By the theory of Modern Geometry, the mechanical principle and advanced calculus, the dynamics in Newtonian_Galilean spacetime is generalized to Newtonian_Riemannian Spacetime, and the dynamics in N_R spacetime is est... 详细信息

关键词： Riemannian manifold connection absolute differential Lie derivative exterior differential co_moving time derivative fiber bundle duality pairing

Existence of SURU estimators in SURE model with special covariance structures

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Chinese Science Bulletin 1997年第14期42卷 1149-1151页

作者： WU QiguangInstitute of Systems Science, Chinese Academy of Sciences, beijing 100080, china Institute of Systems Science Chinese Academy of Sciences Beijing China

THROUGHOUT this note, the following notations are used: For a matrix A, A>0 means thatA is positive definite symmetric; R （A）, A′and A- stand for the column space, transposeand any g-inverse of A respectively; PA = A （A′A）- A′and PA = Ik - PA, where Ik is theidentity matrix of order k that is the number of rows in A. Rm×n is the totality of m×n realmatrices.

关键词： seemingly unrelated regression equations (SURE) model uniformly minimum risk unbiased (UMRU) estimator uniform covariance structure serial covariance structure.

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, beijing 100080, china Graduate School of Chinese Academy of Sciences, beijing 100039, 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.

PURE STATE APPROACH TO C(X) x_αZ_n

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Chinese Annals of Mathematics,Series B 1995年第1期16卷 75-86页

作者： LI BINGREN LIN QING (Institute of Mathematics, Academia Sinica, beijing 100080, china.) 中科院数学所北京

Consider a C*-system (C(X), z n, α), where α is a homeomorphism of X such that α￣n= *** authors characterize the pure state space of C(X) xα z n) the transition probability and orientation on it. Two special case... 详细信息

关键词： C*-crossed product Pure state space Transition probability Orientation.

The Simulation of Influence of Different Coals on the Circulating Fluidized Bed Boiler's Combustion Performance

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Journal of Thermal Science 2003年第2期12卷 185-187,184页

作者： Yumei Yong Qinggang LuInstitute of Engineering Thermophysics, Chinese Academy of Sciences, 100080 beijing, china Institute of Engineering Thermophysics Chinese Academy of Sciences Beijing China

The combustion performance of the boiler largely depends on the coal type. Lots of experimental research shows that different fuels have different combustion characteristics. It is obvious that fuel will change the whole operating performance of Circulating Fluidized Bed Combustion (CFBC). We know even in a pilot-scale running boiler, the measurement of some parameters is difficult and costly. Therefore, we developed the way of simulation to evaluate the combustion performance of Chinese coals in CFB. The simulation results show that, different coals will result in different coal particle diameter and comminution depending on their mineral component and the change will affect the distribution of ash in CFBC system. In a word, the computational results are in accordance with experimental results qualitatively but there are some differences quantitatively.

关键词： coal circulating fluidized bed combustion simulation.