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Multipliers and Cyclic Vectors in Bloch Type Spaces

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Acta Mathematica Sinica,English Series 2003年第1期19卷 79-88页

作者： ZengJianLOU DaoJinSONG DepartmentofComputerSciences ZiboCollegeZibo255091 DepartmentofMathematics ShantouUniversityShantou515063

In this paper we study the coefficient multipliers, pointwise multipliers and cyclic vectors in the Bloch type spaces B^! and little Bloch type spaces $B^\alpha_0$ for 0 < ! < X. We give several full characterizations of the coefficient multipliers (B^!, B^#) and ($B^\alpha_0,$ $B^\beta_0$) for 0 < !, # < X and pointwise multipliers M (B^!, B^#) and M ($B^\alpha_0,$ $B^\beta_0$) for 1 p !, # ] (0, X). We also obtain some properties of cyclic vectors for Bloch type spaces.

关键词： Coefficient multipliers Pointwise multipliers Cyclic vectors Bloch type spaces

Approximation methods of mixed l_1/H_2 optimization problems for MIMO discrete-time systems

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Journal of Systems Engineering and Electronics 2004年第3期15卷 319-326页

作者：李昇平 DepartmentofMechatronicEngineering ShantouUniversityShantou515063P.R.China

The mixed l1/H2 optimization problem for MIMO (multiple input-multiple output) discrete-time systems is considered. This problem is formulated as minimizing the l1-norm of a closed-loop transfer matrix while maintaining the H2-norm of another closed-loop transfer matrix at prescribed level. The continuity property of the optimal value in respect to changes in the H2-norm constraint is studied. The existence of the optimal solutions of mixed l1/H2 problem is proved. Because the solution of the mixed l1/H2 problem is based on the scaled-Q method, it avoids the zero interpolation difficulties. The convergent upper and lower bounds can be obtained by solving a sequence of finite dimensional nonlinear programming for which many efficient numerical optimization algorithms exist.

关键词： MIMO system discrete-time systems mixed l1/H2 optimization.

Investigation and Modification of Coupling of Photonic Crystal Defects

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Chinese Physics Letters 2005年第7期22卷 1698-1701页

作者：林旭升陈雄文兰胜 DepartmentofPhysics ShantouUniversityShantou515063 Information&ElectronTechnologicalInstitute SouthChinaNormalUniversityGuangzhou510631

We investigate the coupling of photonic crystal (PC) defects by usingcoupled-mode theory. The PC molecules formed by the coupling of two identical PC atoms are the focusof our study. It is revealed that the flatness of the transmission spectra of the PC molecules isdetermined uniquely by the phase shift of the travelling wave between the two coupled PC atoms. Byproperly adjusting the distance between the two constitutional PC atoms, we are able to modify thetransmission spectrum of the resulting PC molecule. Theoretical analyses based on the coupled-modetheory are in good agreement with the simulation results obtained by the transfer matrix method andthe finite-difference time-domain technique.

关键词： WAVE-GUIDE MODES TRANSMISSION

Adsorption Behavior for CO on Modified MCM-41 with Zn and CuCl

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Chinese Chemical Letters 2002年第8期13卷 783-786页

作者： NongYueHE QiHongSHI 等 KeyLabofNewMaterialsandTechnologyofChinaNationalPackagingCorporation ZhuzhouEngineeringCollegeZhuzhou412008 DepartmentofChemistry ShantouUniversityShantou515063

The Zn-Cu(I)/HMCM-41 catalysts were successfully prepared in laboratory scale by solid-state ion exchange with CuCl salt, together with introduction of Zn to improve the dispersion degree of the active component Cu(I) on the surface. With increase of the amounts of Zn and CuCl from 0% to 9.0% and 25.0% respectively, CO adsorption the amounts of increased from 10.6 mmol/g to 183.0 mmol/g correspondingly. The in situ FT-IR spectra for CO adsorption demonstrated that there existed two dynamic equilibriums between surface carbonyl complexes: Cu(CO)3+ Cu(CO)2++ CO and Cu(CO)2+ Cu(CO)+ + CO. The equilibriums can be shifted reversibly by changing the temperature and pressure. Due to the modified MCM-41 mesoporous materials possess both of the acidic and metallic carbonyl centers, this kind of material can be developed into mesoporous bifunctional catalysts for carbonylation reactions, in which larger molecules are involved.

关键词： MCM-41 carbon monoxide adsorption carbonylation cuprous.

A Kinetic Evidence for the Nitroxyl Radicals Recycling Mechanism in the Photostabilizing Process of HALS

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Chinese Chemical Letters 2003年第10期14卷 1085-1088页

作者： XiaoXuanLIU XingHongZHANG GuangGuoWU JianWenYANG ZhaoHuaZENG YongLieCHEN DepartmentofChemistry ShantouUniversityShantou515063 InstituteofPolymerScience ZhongshanUniversityGuangzhou510275

The photoinduced bulk polymerization of a reactive-hindered amine light stabilizers (r-HALS), 4-acryloyl-2, 2, 6,6-tetramethylpiperidinyl (ATMP), was performed at 80 C by using a DPC technique. An unique periodic exponential attenuation-type oscillating curve was found when the polymerization was carried out in air, but this phenomenon was not found in nitrogen. It is supposed that this unique kinetic performance may be attributed to nitroxyl radicals that are produced in situ from the oxidation of ATMP. ATMP polymer with narrow polydispersity (d = 1.03) can be obtained by photoinduced solution polymerization of ATMP. The signal detected in ESR may be assigned to the nitroxyl radicals in the matrix of ATMP polymer. Since this kind of recycling of nitroxyl radicals is well documented for the photostabilizing mechanism of HALS, the present results may serve as a kinetic evidence for this mechanism.

关键词： Photopolymerization kinetics reactive-HALS (r-HALS) periodic exponential attenuation-type oscillating cycle photostabilizing mechanism nitroxyl radicals (>N-O).

Identification of Different Cobalt Nucleation on Glassy Carbon

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Chinese Chemical Letters 2004年第8期15卷 981-984页

作者： MinGU FangZuYANG LingHUANG ShiBingYAO ShaoMinZHOU DepartmentofChemistry ShantouUniversityShantou515063 DepartmentofChemistry StateKeyLaboratoryforPhysicalChemistryofSolidSurfacesXiamenUniversityXiamen361005

The nucleation mechanisms of cobalt from sulfate solutions were studied by utilizing the electrochemical technique, chronoamperometry. It was found that the recorded current-time transients introduced from 1.0 mol/L CoSO4 solution were complexes with unusual shapes. All characteristic features were identified as separate process. The instantaneous or progressive nucleation with 2D or 3D growth exists during the cobalt deposition, depending on the applied potentials.

关键词： Cobalt current transient nucleation mechanism.

Interaction of intense laser pulses with atomic clusters at different gas densities

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Chinese Optics Letters 2004年第9期2卷 497-499页

作者：李邵辉王成刘建胜王向欣李儒新倪国权徐至展 DepartmentofPhysics ShantouUniversityShantou515063 LaboratoryforHighIntensityOptics ShanghaiInstituteofOpticsandFineMechanicsChineseAcademyofSciencesShanghai201800

The interaction of intense femtosecond laser pulses with rare gas clusters was studied experimentally, the time-of-flight spectra of ions from exploding clusters at different gas densities have been measured. It is found that while the relative components of ions in low and high energy of the ion energy spectrum decrease with the increase of the gas density, the average ion energies are the same for different gas densities, which indicates that the effect of gas density on laser-cluster interaction is not important under our experimental conditions.

关键词： Atoms Density of gases Ultrashort pulses

THE　COMPUTATION　OF　SYMMETRY－BREAKING　BIFURCATION　POINTS　IN　Z_2×Z_2－SYMMETRIC　NONLINEAR　PROBLEMS

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Applied Mathematics(A Journal of Chinese Universities) 1995年第2期10卷 179-194页

作者： YERUISONG YANGZHONGHUA InstituteofMathematics ShantouUniversityShantou515063 DepartmentofMsthematics ShanghaiUniversityofScienceandTechnologyShanghai201800

This paper is mainly concerned with corank-2 and corank-3 symmetrybreaking bifurcation point in Z2×Z2-symmetric nonlinear problems. Regular extended systems are used to compute corank-2 and corank-3 symmetry--breaking bifurcation points. Two numerical examples are given. In addition, we show that there exist three quadratic pitchfork bifurcation point curves passing through corank-2 symmetry breaking bifurcation point.

关键词： Z_2×Z_2-symmetry symmetry-breaking bifurcation point extended system.

Spontaneous formation of tubular microstructure vesicle from PTA/SDS system

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Chinese Science Bulletin 2005年第9期50卷 857-861页

作者： WANGZhengwu CHENWenjun LIUXiaojun LIGanzuo ZHENGLiqiang ZHANGJin HUANGDongyang KeyLaboratoryofColloidandInterfaceChemistryofMinistryofEducation ShandongUniversityJinan250100China SchoolofChemicalandMaterialEngineering SouthernYangtzeUniversity//KeyLaboratoryofColloidandInterfaceChemistryofMinistryofEducationShandongUniversity//MedicalCollegeShantouUniversity KeyLaboratoryofCrystalMaterialofChina ShandongUniversityJinan250100.China MedicalCollege ShantouUniversityShantou515031China

Spontaneous vesicle formation and transforma- tion of vesicle to tubular microstructure have been observed in aqueous mixtures of tri-(n-dodecyl-dimethyl-hydroxy- propylammonium chloride) phosphate (PTA) and sodium dedecyl sulfate (SDS), which is supported by negative-stain- ing transmission electron microscopy (TEM), scan electron microscopy (SEM) and dynamic light scattering (DLS). Spherical vesicles aggregate to tubular microstructures with their diameters and lengths respectively of about 100 and 7000 nm in the freshly prepared sample at the molar ratio of PTA/SDS=3/7 and a total surfactant concentration of 0.01 mol/L. The diameter, the length and the quantity of tubular structures all increase with the increase of the total concen- tration of surfactant and the sample aging.

关键词：囊泡管状显微结构磷酸盐负着色TEM