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91.
ZDRAVKOVICS SATARICM.V 《中国物理快报》2005,22(4):850-852
We compare optical and acoustical frequencies in the Peyrard-Bishop-Dauxois model, i.e. an extended Peyrard-Bishop model, of DNA molecules. We discuss how ratio of those frequencies depends on a value of the harmonic constant of the helicoidal spring K. Also, we suggest that the most favourable mode could be a resonance mode. 相似文献
92.
Pre—Separation Axioms in Fuzzifying Topology 总被引:1,自引:0,他引:1
K.M.AbdEl-Hakeim F.M.Zeyada 《模糊系统与数学》2003,17(1):28-36
1 IntroductionYing[5,6 ] introduced and elementally developed so called fuzzifying topology with the semanticmethod of continuous valued L ogic.Shen[7] introduced and studied T0 -,T1-,T2 (Hausdorff) -,T3(regularity) -,T4 (normality) -separation axioms in fuzzifying topology.In [3 ]the concepts of thefamily of fuzzifying pre-open sets,fuzzifying pre-neighbourhood structure of a point and fuzzifyingpre-closure are introduced and studied.It is worth to mention that pre-separation axioms are … 相似文献
93.
Nikolaos S. PAPAGEORGIOU Nikolaos YANNAKAKIS 《数学学报(英文版)》2005,21(5):977-996
This is the first part of a work on second order nonlinear, nonmonotone evolution inclusions defined in the framework of an evolution triple of spaces and with a multivalued nonlinearity depending on both x(t) and x(t). In this first part we prove existence and relaxation theorems. We consider the case of an usc, convex valued nonlinearity and we show that for this problem the solution set is nonempty and compact in C^1 (T, H). Also we examine the Isc, nonconvex case and again we prove the existence of solutions. In addition we establish the existence of extremal solutions and by strengthening our hypotheses, we show that the extremal solutions are dense in C^1 (T, H) to the solutions of the original convex problem (strong relaxation). An example of a nonlinear hyperbolic optimal control problem is also discussed. 相似文献
94.
H.Yurtseven H.Kaya 《中国物理快报》2003,20(1):35-38
This study gives our calculation for the specific heats CVI due to an Ising model using the observed Cp data for the Ⅱ-Ⅲ and Ⅱ-VI phase transitions in NH4I.By fitting to the CP data we determine the values of the critical exponent for the pressure of 0.14GPa(Ⅱ-Ⅲ phase transition)and for the pressures of 0.75,1.35and 1.97 GPa (II-IV phase transition)in NH4I.Our exponent values values are close to the predicted values of the specific heat in a three-dimensional Ising model.Our calculated CVI are in good agreement with the experimental CP for NH4I in most cases. 相似文献
95.
S.BOUZID Z.AZARI 《宁波大学学报(理工版)》2003,16(4):354-362
冲蚀过程是一个与颗粒反复冲击物体表面而移除物质相关的表面现象.本文研究了玻璃的冲蚀坑的几何尺寸和体积,给出了冲蚀移除物质如何依赖于颗粒流动速度、颗粒尺寸和冲击角的理论关系.通过理论与实验结果相比较,定义了一定冲蚀坑尺度的有效域. 相似文献
96.
ZhuZhiyong DuanJinlai SunYoumei Y.Maekawa H.Koshikawa M.Yoshida 《近代物理研究所和兰州重离子加速器实验室年报》2003,(1):68-70
Heavy ion irradiated polymers can be chemically etched to form track membrane with pores in the micro and sub-micro ranges. It has been reported that pore growth during etching can be related to track structures. A latent track has a track core inside and a track halo surrounding the track core. By single track etching it is observed that etching in the track core is much faster than in the track halo where the etching rate is even lower tlian that of bulk material. For multi-track etching, no such stages can be seen by the conductance measurements. 相似文献
97.
The interleukin 1β (IL-1β) cDNA was cloned from the red seabream (Pagrus major) by homology cloning strategy. A cDNA fragment was amplified by PCR using two degenerated primers, which were designed according to the conserved regions of other known IL-1β sequences, and elongated by 3' ends and 5' ends RACE PCR to get the full length coding sequence of red seabream IL-1β (RS IL-1β). The sequence contained 1252 nucleotides that included a 5' untranslated region (UTR) of 84bp, a 3' UTR of 410 bp and an open reading frame (ORF) of 759 nucleotides which could be translated into a putative peptide of 253 amino acids with molecular weight of 28.6 kD and putative isoelectric point pI of 5.29. The deduced peptide contained two potential N-glycosylation sites and an identifiable IL1 family signature, but lacked the signal peptide and the clear ICE cut site, which were common in other nonmammalian IL-1β genes. The RS IL-1β had the highest homology with piscine IL-1β according to phylogenetic tree analysis. 相似文献
98.
在《魔兽争霸3》中,Human一直是以防御见长的种族。Footman抵挡穿刺攻击的Defense技能,Paladin的防御光环和Priest的Inner Fire魔法都是用以加强部队防御力量的。而且Human是《魔兽争霸3》中综合移动速度最慢的种族。不但只有Knight具有比较快的移动速度,而且没有任何加速的光环和魔法加以辅助。基于Human的这种特点,以 相似文献
100.
The SmF_(2.01)was synthesized by reducing SmF_3 in H_2 stream.As it was doped inKM_gF_3 and KCaF_3.there was emission of Sm~(2+) in KMgF_3 but no emission of Sm~(2+) inKCaF_3 was observed. 相似文献