共查询到20条相似文献,搜索用时 15 毫秒
1.
2.
3.
In this paper, an axicon, which is combined a symmetrically cubic phase plate with a perfect lens, is introduced. Based on stationary phase method and the numerical calculation, the diffraction field behind the axicon is investigated. It is shown that, by using this kind of axicons, we can obtain the uniform-intensity focal segment within the desired range. 相似文献
4.
5.
Álvaro González García Jasper V. Maring Joeri Opdam Henricus H. Wensink Henk N. W. Lekkerkerker 《Molecular physics》2018,116(21-22):2757-2772
ABSTRACTFree volume theory (FVT) is a versatile and tractable framework to predict the phase behaviour of mixtures of platelets and non-adsorbing polymer chains in a common solvent. Within FVT, three principal reference phases for the hard platelets are considered: isotropic (I), nematic (N) and columnar (C). We derive analytical expressions that enable us to systematically trace the different types of phase coexistences revealed upon adding depletants and confirm the predictive power of FVT by testing the calculated diagrams against phase stability scenarios from computer simulation. A wide range of multi-phase equilibria is revealed, involving two-phase isostructural transitions of all phase symmetries (INC) considered as well as the possible three-phase coexistences. Moreover, we identify the system parameters, relative disk shapes and colloid–polymer size ratios, at which four-phase equilibria are expected. These involve a remarkable coexistence of all three-phase states commonly encountered in discotics including isostructural coexistences I1–I2–N–C, I–N1–N2–C and I–N–C1–C2. 相似文献
6.
7.
8.
9.
10.
11.
Non-additivity effects in coupled dynamic-stochastic systems are investigated. It is shown that there is a mapping of the
replica approach to disordered systems with finite replica indexn on Tsallis non-extensive statistics, if the average thermodynamic entropy of the dynamic subsystem differs from the information
entropy for the probability distribution in the stochastic subsystem. The entropic indexq is determined by the entropy difference ΔS. In the case of incomplete information, the entropic indexq=1−n is shown to be related to the degree of lost information. 相似文献
12.
13.
14.
15.
B. I. Stepanov Institute of Physics, Academy of Sciences of Belarus, 70, F. Skorina Ave., Minsk, 220072, Belarus. Translated
from Zhurnal Prikladnoi Spektroskopii, Vol. 62, No. 2, pp. 200–205, March–April, 1995. 相似文献
16.
17.
Metsaev和Tseytlin(MT)给出的AdS5S5背景中Green-Schwarz(GS) IIB超弦的Polyakov作用量可以写成等价的Nambu-Goto形式.对于这种形式,给出了新的与靶空间的流有关的投影算子,并用其构造了使作用量不变的局域κ-变换.κ-对称性的这种新方案是由Schwarz对于GS模型提出的.由于MT模型与GS模型有所不同,文中所构造的局域κ-变换有一些新的特点,且适用于其他类似于MT模型的系统.文中分别以AdS5S1背景中IIB弦及Polyakov新提出的模型为例,构造了κ-对称性的靶空间形式.
关键词:
Green-Schwarz超弦
κ-对称性')" href="#">κ-对称性
AdS5S5')" href="#">AdS5S5
AdS5S1')" href="#">AdS5S1 相似文献
18.
19.
20.