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91.
92.
Dragan DJURCIC Aleksandar TORGASEV 《数学学报(英文版)》2006,22(3):689-692
In this paper, we prove some properties of the Seneta sequences and functions, and in particular we prove a representation theorem in the Karamata sense for the sequences from the Seneta class SOc. 相似文献
93.
Elói Medina Galego 《Monatshefte für Mathematik》2002,136(2):87-97
We study the relation of to the subspaces and quotients of Banach spaces of continuous vector-valued functions , where K is an arbitrary dispersed compact set. More precisely, we prove that every infinite dimensional closed subspace of totally incomparable to X contains a copy of complemented in . This is a natural continuation of results of Cembranos-Freniche and Lotz-Peck-Porta. We also improve our result when K is homeomorphic to an interval of ordinals. Next we show that complemented subspaces (resp., quotients) of which contain no copy of are isomorphic to complemented subspaces (resp., quotients) of some finite sum of X. As a consequence, we prove that every infinite dimensional quotient of which is quotient incomparable to X, contains a complemented copy of . Finally we present some more geometric properties of spaces.
Received 8 November 2000; in revised form 7 December 2001 相似文献
94.
Marston Conder Aleksander Malnič Dragan Marušič Primž Potočnik 《Journal of Algebraic Combinatorics》2006,23(3):255-294
A list is given of all semisymmetric (edge- but not vertex-transitive) connected finite cubic graphs of order up to 768. This
list was determined by the authors using Goldschmidt's classification of finite primitive amalgams of index (3,3), and a computer
algorithm for finding all normal subgroups of up to a given index in a finitely-presented group. The list includes several
previously undiscovered graphs. For each graph in the list, a significant amount of information is provided, including its
girth and diameter, the order of its automorphism group, the order and structure of a minimal edge-transitive group of automorphisms,
its Goldschmidt type, stabiliser partitions, and other details about its quotients and covers. A summary of all known infinite
families of semisymmetric cubic graphs is also given, together with explicit rules for their construction, and members of
the list are identified with these. The special case of those graphs having K1,3 as a normal quotient is investigated in detail.
Supported in part by N.Z. Marsden Fund (grant no. UOA 124) and N.Z. Centres of Research Excellence Fund (grant no. UOA 201)
Supported in part by “Ministrstvo za šolstvo, znanost in šport Slovenije”, research program no. 101-506.
Supported in part by research projects no. Z1-4186-0101 and no. Z1-3124-0101. The fourth author would like to thank the University
of Auckland for hospitality during his visit there in 2003. 相似文献
95.
96.
Measurement of small-signal and large-signal responses of packaged laser modules at high temperature
Ning Hua Zhu Ji Min Wen Hai Peng Song Shang Jian Zhang Liang Xie 《Optical and Quantum Electronics》2006,38(15):1245-1257
In this paper, the pulsed injection method is extended to measure the chip temperature of various packaged laser modules,
such as the DFB laser modules, the FP laser modules, and the EML laser modules. An optimal injection condition is obtained
by investigating the dependence of the lasing wavelength on the width and period of the injection pulse in a relatively wide
temperature range. The small-signal frequency responses and large-signal performances of packaged laser modules at different
chip temperature are measured. The adiabatic small-signal modulation characteristics of packaged LD are first extracted. In
the large-signal measurement, the effects of chip temperature, bias current and driving signal on the performances of the
laser modules are discussed. It has been found that the large-signal performances of the EML modules depend on the different
red-shift speeds of the DFB and EAM sections as chip temperature varying, and the optimal characteristics may be achieved
at higher temperature. 相似文献
97.
Yu ZHANG Ji Tao SUN 《数学学报(英文版)》2006,22(3):813-818
In this paper, we will extend the strict stability to impulsive differential equations. By using Lyapunov functions, we will get some criteria for the strict stability of impulsive differential equations, and we can see that impulses do contribute to the system's strict stability behavior. An example is also given in this paper to illustrate the efficiency of the obtained results. 相似文献
98.
Chen Hou Chunnuan Ji Chunhua Wang Rongjun Qu 《Journal of polymer science. Part A, Polymer chemistry》2006,44(1):226-231
The reverse atom‐transfer radical polymerization (RATRP) technique using CuCl2/2,2′‐bipyridine (bipy) complex as a catalyst was applied to the living radical polymerization of acrylonitrile (AN). A hexasubstituted ethane thermal iniferter, diethyl 2,3‐dicyano‐2,3‐diphenylsuccinate (DCDPS), was firstly used as the initiator in this copper‐based RATRP initiation system. A CuCl2 to bipy ratio of 0.5 not only gives the best control of molecular weight and its distribution, but also provides rather rapid reaction rate. The rate of polymerization increases with increasing the polymerization temperature, and the apparent activation energy was calculated to be 57.4 kJ mol?1. Because the polymers obtained were end‐functionalized by chlorine atoms, they were used as macroinitiators to proceed the chain extension polymerization in the presence of CuCl/bipy catalyst system via a conventional ATRP process. © 2005 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 44: 226–231, 2006 相似文献
99.
Chen Hou Rongjun Qu Chunnuan Ji Chunhua Wang Chengguo Wang 《Journal of polymer science. Part A, Polymer chemistry》2006,44(1):219-225
FeCl3 coordinated by isophthalic acid was first used as a catalyst in the azobisisobutyronitrile‐initiated reverse atom transfer radical polymerization of acrylonitrile. N,N‐Dimethylformamide was used as a solvent to improve the solubility of the ligand. An FeCl3‐to‐isophthalic acid ratio of 0.5 not only gave the best control of the molecular weight and its distribution but also provided rather a rapid reaction rate. The effects of different solvents on the polymerization of acrylonitrile were also investigated. The rate of the polymerization in N,N‐dimethylformamide was faster than that in propylene carbonate and toluene. The molecular weight of polyacrylonitrile agreed reasonably well with the theoretical molecular weight in N,N‐dimethylformamide. The rate of polymerization increased with increasing polymerization temperature, and the apparent activation energy was calculated to be 59.9 kJ mol?1. Reverse atom transfer radical polymerization was first used to successfully synthesize acrylonitrile polymers with a molecular weight higher than 80,000 and a narrow polydispersity as low as 1.22. © 2005 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 44: 219–225, 2006 相似文献
100.
Many sets of the soliton and periodic travelling wave solutions for the quadratic χ^(2) nonlinear system are obtained by the Backlund transformation and the trial method. The property of the propagation for some travelling waves is investigated. 相似文献