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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, beijing 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 GM4D = 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

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

Cyclic Heating-Annealing and Boltzmann Distribution of Free Energies in a Spin-Glass System

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Communications in theoretical physics 2007年第7期48卷 179-182页

作者： ZHOU Hai-Jun institute of theoretical physics,the chinese academy of sciences,beijing 100080,china institute of theoretical physics the Chinese Academy of Sciences Beijing 100080 China

Ergodicity of a spin-glass is broken at low temperatures;the system is trapped in one of many ergodicconfigurational *** between different ergodic domains are achievable through a *** this experiment is repeated infinite times,all ergodic configurational domains will be visited with frequencesthat decreasing exponentially with their free *** mean free energy density of a spin-glass system on a randomgraph is calculated based on this free energy Boltzmann distribution in the present work,by means of the cavity approach.

关键词： spin-glass ergodicity-broken cavity method

From quantum spectra to classical orbits: Varying rectangular billiards

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Progress in Natural Science:Materials International 2008年第8期18卷 927-930页

作者： Jun Lu * Department of Foundational Science, beijing Union University, beijing 100101, china institute of theoretical physics, chinese academy of sciences, beijing 100080, china Department of Foundational Science Beijing Union University Beijing 100101 China institute of theoretical physics Chinese Academy of Sciences Beijing 100080 China

The quantum-spectrum function is introduced by means of the eigenvalues and the eigenfunctions in the system of varying rectangular billiards. It is found that the Fourier transform of the quantum-spectrum function corresponds with the classical orbits in the system. These results give new evidence about the classical-quantum correspondence.

关键词： Quantum spectrum Classical-quantum correspondence Semiclassical physics

Finding Signals for Plant Promoters

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Genomics, Proteomics & Bioinformatics 2003年第1期1卷 68-73页

作者： Weimou Zhenginstitute of theoretical physics, chinese academy of sciences, beijing 100080, china beijing Genomicsinstitute, chinese academy of sciences, beijing 101300, china institute of theoretical physics Chinese Academy of Sciences Beijing 100080 China beijing Genomics institute Chinese Academy of Sciences Beijing 101300 China

The strongest signal of plant promoter is searched with the model of single motif with two types. It turns out that the dominant type is the TATA-box. The other type may be called TATA-less signal, and may be used in gene finders for promoter recognition. While the TATA signals are very close for the monocot and the dicot, their TATA-less signals are significantly different. A general and flexible multi-motif model is also proposed for promoter analysis based on dynamic programming. By extending the Gibbs sampler to the dynamic programming and introducing temperature, an efficient algorithm is developed for searching signals in plant promoters.

关键词： for on is as et Pro Finding Signals for Plant Promoters been of into

SYNTHESIS AND CHARACTERIZATION OF NEW STABILIZERS WITH OPTIMAL MOLECULAR WEIGHT

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chinese Journal of Polymer Science 2001年第4期19卷 341-350页

作者： Jiang-qing Pan institute of Chemistry chinese academy of sciences, beijing 100080 china 中科院化学所北京

Over 2 x 10(8) tons of polymers are produced every year, and a large portion of polymers faces the degradation problem. There are many effective methods to protect polymers against degradation and the addition of stabilizers to polymer remains the most convenient and effective way of enhancing polymer life and performance. In this article, a series of effective stabilizers with optimal molecular weight (MW), including common, monomeric and polymeric stabilizers (antioxidant and light stabilizer) were synthesized using isocyanation, controlled isocyanation, hydrosilylation, epoxide addition, macroreaction of stabilizing functional compounds and polymerization of monomeric stabilizers. The structure and performance of these new stabilizers were characterized by using IR, NMR, MS, UV-spectra, XPS and elemental analysis. The current development of stabilizer synthesis was also reviewed.

关键词： preparation of stabilizer antioxidant hindered amine light stabilizer isocyanation hydrosilylation

Physical aging in Zr_(46.75)Ti_(8.25)Cu_(7.5)Ni_(10)Be_(27.5) typical bulk metallic glass manifested as enthalpy relaxation

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Science china(physics,Mechanics & Astronomy) 2008年第4期51卷 356-364页

作者： WEN Ping,ZHAO ZuoFeng & WANG WeiHua institute of physics,chinese academy of sciences,beijing 100080,china institute of physics Chinese Academy of Sciences Beijing China

Enthalpy recovery is not only an important characteristic of physical aging of glass,but also a good tool to investigate the physical aging. Using differential scanning calorimeter (DSC),the enthalpy recovery of Zr46.75Ti8.25Cu7.5Ni10Be27.5 bulk metallic glass (BMG) was studied. The typical characteristics of enthalpy recovery of glass including the sub-Tg peak and ‘overshot’ were found in BMG. The evolution of the sub-Tg peak and ‘overshot’ were described by the free volume theory and Hodge’s model,respectively. It was found that the former failed to describe the enthalpy recovery in the BMG,while the latter could give a qualitative explanation. In com-bination with the dynamics in the BMG,the origin of the enthalpy recovery in the BMG was discussed. The results show that BMGs are an ideal material to investi-gate the physical aging. The further understanding of physical aging of BMGs is useful to clarify the nature of glass and improve the application and device of new types of BMGs.

关键词： bulk metallic glass enthalpy recovery physical aging

Linear relationship between the interdecadal and interannual variabilities of North china rainfall in rainy season

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chinese Science Bulletin 2003年第10期48卷 1040-1044页

作者： LU Riyu institute of Atmospheric physics, chinese academy of sciences, beijing 100080, china institute of Atmospheric physics Chinese Academy of Sciences Beijing 100080 China

Interdecadal and interannual timescales are dominant in the North china rainfall in rainy season (July and August). On the interdecadal timescale, the North china rainfall exhibited an abrupt decrease at the end of 1970s. In this study, we examined the effect of this abrupt rainfall decrease on the association between rainfall and circulation on the interannual timescale, and found that the interdecadal variation does not change the physical mechanism responsible for the interannual variation of North china rainfall. There is a linear relationship between the interdecadal and interannual variabilities of North china rainfall in rainy season.

关键词：线性关系中国北部降雨量大气环流

Transformations and non-degenerate maps

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Science china Mathematics 2005年第z1期48卷 195-205页

作者： LI Baokui & WANG Yuefei institute of Mathematics, academy of Mathematics and System sciences, chinese academy of sciences, beijing 100080, china Graduate School, chinese academy of sciences, beijing 100080, china institute of Mathematics Academy of Mathematics and System Sciences Chinese Academy of Sciences Beijing China Graduate School Chinese Academy of Sciences Beijing China

We shall prove the equivalences of a non-degenerate circle-preserving map and a M(o)bius transformation in ^Rn, of a non-degenerate geodesic-preserving map and an isometry in Hn of a non-degenerate line-preserving map and an affine transformation in Rn. That a map is non-degenerate means that the image of the whole space under the map is not a circle, or geodesic or line respectively. These results hold without either injective or surjective, or even continuous assumptions, which are new and of a fundamental nature in geometry.

关键词： M(o)bius transformation, circle-preserving map, non-degenerate map.