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1.
LIU Xiao-ying XIA Shi-fa LI Fang-yu 《重庆大学学报(英文版)》2005,4(4):243-246
1 Introduction a In theoretical physics, the problem of calculating the quantum entropy on black hole background is a hotspot. Much efforts have been devoted to study the quantum entropy via brick-wall model [1] in the last 20 years, and most conclusions [2-6] are the quantum entropy according with Bekenstein-Hawking equation, i.e. S = Ah / 4 where S is the quantum entropy; and Ah is the area of the black hole horizon. But recent research [7,8] shows that the quantum entropy also has the log… 相似文献
2.
Topological inverse semigroups 总被引：5，自引：0，他引：5
ZHUYongwen 《重庆大学学报(英文版)》2004,3(1):82-85
That the projective limit of any projective system of compact inverse semigroups is also a compact inverse semigroup,the injective limit of any injective system of inverse semigroups is also an inverse semigroup, and that a compact inversesemigroup is topologically isomorphic to a strict projective limit of compact metric inverse semigroups are proved. It is alsodemonstrated that Horn (S,T) is a topological inverse semigroup provided that S or T is a topological inverse semigroup withsome other conditions. Being proved by means of the combination of topological semigroup theory with inverse semigroup theory,all these results generalize the corresponding ones related to topological semigroups or topological groups. 相似文献
3.
This thesis focus on the analysis of the motive of the two murders made by Bigger Thomas, a black man. The black people＇s miserable living condition is one of the reasons why the two murders happened. The white＇s bias towards the black is also responsible for them. Bigger Thomasg deformed, distorted personality is also part of the explanations for the murders. 相似文献
4.
Using φ-mapping method and topological current theory,the topological structure of disclination lines in 2-dimensional liquid crystals is studied.By introducing the strength density and the topological current of many disclination lines,it is pointed out that the disclination lines are determined by the singulaities of the director field,and topologically quantized by the Hopf indices and Brouwer degrees,Due to the equivalence in physics of the director fields n(x) and -n(x),the Hopf indices can be integers or half-integers,representing a generalization of our previous studies of integer Hopf indices. 相似文献
5.
Architecture singularity of a parallel mechanism with five degrees of freedom (DOF) is analyzed. Such mechanism consists of a movable platform connected to the base by five active limbs. Four of them are identical 6-DOF limbs and the last one has the same DOF as the specified DOF of the movable platform. Based on the kinematics analysis, two categories of architecture singularities for such mechanism are proposed. Then the sufficient condition for each singularity is researched. Results show that the mechanism is singular when it employs each category of the proposed architecture, provided that it satisfies the corresponding sufficient condition. It can be concluded that the proposed two categories of architecture singularities should be avoided with the following dimensional synthesis of such mechanism. 相似文献
6.
As an important type of polynomial approximation, approximation of functions by Bernstein operators is an important topic in approximation theory and computational theory. This paper gives global and pointwise estimates for weighted approximation of functions with singularities by Bernstein operators. The main results are the Jackson＇s estimates of functions f∈ （Wwλ）2 andre Cw, which extends the result of （Della Vecchia et al., 2004）. 相似文献
7.
The structure phase transformations of graphite and carbon black induced by pulsed laser were studied in this paper.Under irradiation with laser beam of 1.06 μm wavelength and power density of 106 W·cm-2,both graphite structure and carbon black structure were changed obviously.The results of Raman analyses and Transmission Electron Microscopy(TEM)observations show that graphite transforms into nanodiamond about 5 nm and carbon black is graphitized.It is demonstrated that graphite is the intermediate phase in the transformation from carbon black to diamond,and graphite is easier to transform into diamond by laser irradiation than carbon black. 相似文献
8.
Hydroxyapatite bioceramics is simulated by using finite element method (FEM).The influences of porosity,hole shape,angle of crack and other parameters on the ceramics are analyzed.The results show that with the increase of the angle between crack and horizontal direction,the stress intensity factor KⅠdecreases gradually,but stress intensity factor K II increases at first and then it decreases.The value of K Ⅱ reaches maximum when the angle between crack and horizontal direction is 45°.KⅠ and K Ⅱ rise with the increase of porosity,and they are almost the same for the circular and hexagonal holes.For elliptical holes,KⅠand KⅡreach maximum when the long axis of ellipse is perpendicular to the loading direction and they reach minimum when the same axis is parallel to the loading direction.Moreover,with the increase of the angle between the long axis and loading direction,KⅠ and KⅡ increase gradually. 相似文献
9.
Two-photon Jaynes-Cummimgs model is generalized to the case of Kerr medium in this paper,The field and atom are prepared initially in two-photon superposition state and ground state respectively.Nonlinear coefficient affects the dynamic behaviors of the field and atom.Evolutions of the squeezing for the operators of field and atom and the quantum inversion are discussed.In particular,the higher-order squeezing for atomic dipole and the effects of nonlinearity on it,which have not been studied by other authors,are investigated,Increasing the nonlinear coefficient will decrease the squeezing depth of atomic dipole. 相似文献
10.
Generalized cone-subconvexlike set-valued maps and applications to vector optimization 总被引：1，自引：0，他引：1
The definitions of cone-subconvexlike st-valued maps and generalized cone-subconvexlike set-valued maps in topological vetor spaces are defined by using the relative interiors of ordering cone.The relationships between the two classes of set-valued maps are investigated.and some properties of them are shown.A Gordan type alternative theorem under the assumption of generalized cone-subconvexlikeness of set-valued maps is proved by applying convex separation theorems involoving the relative interiors in infinite dimensional spaces.Finally a necessary optimality condition theorem is shown for a general kind of set-valued vector optimization in a sense of weak E-minimizer. 相似文献
11.
A rice mutant with Yaponica 9522 cultivar background Oryza sativa extraordinary glume 1 （Oseg 1） was identified from the M2 mutant pool mutagenized by ^60Co γ-ray. Compared with wild type plants, Oseg 1 developed longer empty glumes and rudimentary glumes. In some Oseg 1 mutants, the number of stamens of flowers was reduced and leaf-like lodicules occurred, and excessive lemma/palea-like organ could be observed in some mutant spikelets. This indicated that OsEG1 could regulate the development of rudimentary glumes, empty glumes, lemma/palea, lodicules, and stamens. Genetic analysis indicated that Oseg 1 came from a single recessive genetic locus. To clone OsEG1 gene, F2 population was constructed by a cross between Oseg 1 （Japonica） and Guangluai4 （Indica）. Using map-based cloning approach, OsEG1 was mapped on chromosome 4, between INDEL marker OS407 and WHM0466 with genetic distance of 2.0 cm and 1.0 cm, respectively. These results are useful for further cloning and functional analysis of the OsEG1 gene. 相似文献
12.
In this note, we prove that the convergence rate of the modified Gauss-Seidel (MGS) method with preconditional I Sa isa monotonic function of preconditioning parameter a. Based on this result, to achieve better convergence rate we suggest proformingtwice preconditoning when applying the MGS method to solve a linear system whose coefficient matrix is an irreducible non-singularM-matrix. 相似文献
13.
Exchange coupling and magnetization reversal mechanism in two series of Co_xNi_(1-x)/CoO(30 nm)(x=0.2 and 0.4)bilayers are studied by vector magnetometer.Two components of magnetization are measured parallel and perpendicular to the applied field.At low temperatures,coercivity H_c∝(t_(FM))~(-n),n=1.5 and 1.38 for x=0.2 and 0.4,respectively,in agreement with the random field model.At room temperature,the coercivity is nearly proportional to the inverse FM layer thickness.In addition to the exchange field and the coercivity,the characteristic of the magnetization reversal mechanism was found to change with temperature.At temperatures below 180 K,magnetization reversal process along the unidirectional axis is accompanied only by nucleation and pinning of domain wall while magnetization rotation is also involved at high temperatures. 相似文献
14.
几乎正则图的全符号控制 总被引：1，自引：2，他引：1
1IntroductionFor notation and graph theory terminology we ingeneral follow[1].LetG=(V,E)be a graph with thevertex setVand the edge setE,andletvbe a vertexinV.The open neighborhood ofvisN(v)={u∈V|uv∈E}and the closed neighborhood ofvisN[v]={v}∪N(v).The d… 相似文献
15.
n-soliton-like solutions of three non-isospectral equations, the non-isospectral mKdV equation, the non-isospectral sine-Gordon equation and the non-isospeetral nonlinear Schroedinger equation were obtained by using the Hirota method. 相似文献
16.
The Bacillus firmus was immobilized into Ca-alginate beads according to the different initial biomass concentration, calcification time and activation time.Three types of immobilized Bacillus firmus beads were packed respectively in trickling biofilter to purify xylene contained waste gases,and the performance of immobilized-cell biofilter was compared with traditional biofilm attached biofilter packed with two types of ceramic pellets.The results showed that three types of immobilized beads had different capabilities for removing xylene and life-spans.Higher initial biomass in immobilized beads resulted in better performance but shorter life-span.Activation process can remarkably enhance the activity of bacteria,and the removal efficiency of xylene can substantially be improved.Calcification time had influence on life-span of immobilized beads.Without acclimation,the cell-entrapped biofilter can obtain the maximum elimination capacity of 92.4 g/(m~3·h).However,compared with biofilm attached biofilter,it has a poorer intrinsic drawback in volatile organic compounds (VOCs) removal due to the existence of excess mass transfer resistance. 相似文献
17.
A laboratory-scale trickling biofilter column,filled with Raschig rings and inoculated with Pseudomonas putida (ATCC 1785)was used to purify chlorobenzene contained waste gases.Sodium dodecyl sulfonate(SDS)was used to enhance the performance of trickling biofllter.Purification performance of the trickling biofilter was examined for chlorobenzene inlet concentration of 1.20～5.04 g/m~3 at different EBRTs between 76～153 s.Without SDS addition,with simultaneous increase in chlorobenzene inlet loading rate and gas flow rate,100% removal efficiency was achieved at EBRT of 109 s and inlet loadings below 5120 mg/m~3.Addition of SDS to nutrient solution led to improvement of trickling biofilter purification performance. By introducing 25 mg/L SDS,the removal efficiency was increased by 21% and elimination capacity up to 234 g/(m~3.h)was achieved at chlorobenzene inlet loading of 241 g/(m~3.h).Although SDS concentration experienced a low rate reduction after continuous nutrient solution recirculation,this result has little influence on trickling biofilter's removal efficiency in monitoring period. 相似文献
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19.
In this paper we study the scaling behavior of nucleotide cluster in 11 chromosomes of Encephalitozoon cuniculi Genome. The statistical distribution of nucleotide clusters for 11 chromosomes is characterized by the scaling behavior of P（S） ∝ e^-αs＇ where S represents nucleotide cluster size. The cluster-size distribution P（S1＋S2） with the total size of sequential C-G cluster and A-T cluster S1＋S2 were also studied. P（S1＋S2） follows exponential decay. There does not exist the case of large C-G cluster following large A-T cluster or large A-T cluster following large C-G cluster. We also discuss the relatively random walk length function L（n） and the local compositional complexity of nucleotide sequences based on a new model. These investigations may provide some insight into nucleotide cluster of DNA sequence. 相似文献
20.
In an effort to find the effect of mass transfer ,surface tesion and drag forces on the velocity distribution,the mathematical model of the velocity profile of a nascent hollow fiber during membrane formation in the air gap region was numerically simulated by using the Runge-Kutta method (fourth-order method).The effect of mass transfer on velocity distribution based on the complicated function(G(Ch^s))was presented and the dffects of a complicated function were studied in two cases:in the first case,G(Ch^s) was constant;in the second,G(Ch^s) was variable.The latter was done by varying with the concentration of solvent in a nascent hollow fiber through the air-gap region.One empirical equation was used to describe this change and the predected values had a better agreement with the experimental values.To verify the moedl hypotheses,hollow fiber membranes were spun from 20:80 polybenzimidazole/polyetherimide dopes with 25.6 wt％ solid in N,N-dimethylacetamide (DMAc) using water as the external and internal coagulants.Based on the experimental results of dry-jet wet-spinning process for the fabrication of hollow fiber membranes,it is found that the model calculated values were in a good agreement with the experimental values. 相似文献