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The equations of state for liquids and liquid solutions with intermolecular hydrogen bonds were derived in the dichotomous noise model for these bonds. The analytically obtained PT and TC phase diagrams show that finite-lifetime bonds can be responsible for new experimentally found phase transitions. These are (i) stratification of solutions in a closed TC region (i.e., a region with upper and lower critical points) and in a low-concentration TC region and (ii) low-temperature stratification of monomolecular liquids into heavy and light phases. 相似文献
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We discuss the notion of spin squeezing considering two mutually exclusive classes of spin-s states, namely, oriented and non-oriented states. Our analysis shows that the oriented states are not squeezed while non-oriented
states exhibit squeezing. We also present a new scheme for construction of spin-s states using 2s spinors oriented along different axes. Taking the case of s=1, we show that the ‘non-oriented’ nature and hence squeezing arise from the intrinsic quantum correlations that exist among
the spinors in the coupled state. 相似文献
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Lyakhova KS Horvat A Zvelindovsky AV Sevink GJ 《Langmuir : the ACS journal of surfaces and colloids》2006,22(13):5848-5855
We have used dynamic self-consistent field (DSCF) theory to investigate the structural evolution of an ABA block copolymer thin film placed between a solid substrate and a free surface. In line with the few existing theoretical studies for pure homopolymers and mixtures, the free interface is introduced by a void component. In our calculations, the free surface experiences surface roughening and eventually the formation of terraces, as in the experiments. The kinetic pathway of the microstructures was compared to findings of an existing detailed experimental study (Knoll, A.; Lyakhova, K. S.; Horvat, A.; Krausch, G.; Sevink, G. J. A.; Zvelindovsky, A. V.; Magerle, R. Nat. Mater. 2004, 3, 886) and was found to be equivalent in detail. This corroborates our assumption in this earlier work that the pathway due to changing film thickness is similar to a pathway due to changing surface energetics. Moreover, our calculations show for the first time that microstructural transitions are a driving force of polymer/air interface curving and the formation of terraces. 相似文献
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The aim of this brief report is to study the behaviour of sheath structure in a multi-component plasma with dust-neutral collisions.
The plasma consists of electrons, ions, micron size negatively charged dust particles and neutrals. The sheath-edge potential
and sheath width are calculated for collisionally dominated sheath. Comparison of collisionless and collisionally dominated
sheath are made. 相似文献
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Hamley IW Castelletto V Mykhaylyk OO Yang Z May RP Lyakhova KS Sevink GJ Zvelindovsky AV 《Langmuir : the ACS journal of surfaces and colloids》2004,20(25):10785-10790
The mechanism of the transition from a lamellar phase to a gyroid phase in an aqueous solution of a diblock copolymer has been studied by time-resolved synchrotron small-angle X-ray scattering. The transition occurs via a metastable perforated lamellar structure. The perforations initially have liquidlike ordering before developing hexagonal packing. The transient phase of irregularly perforated layers is revealed by the development of diffuse scattering peaks, just below the Bragg peaks of the lamellar structure. The diffuse scattering is modeled by Monte Carlo simulations of perforated layers. Following the formation of perforations, Bragg peaks characteristic of a hexagonal structure signal an ordering into a hexagonal lattice (with the concomitant loss of diffuse scattering). Computer simulations based on a dynamic density functional model reproduce these features. The hexagonal perforated lamellar phase is rapidly replaced by the gyroid phase. The domain spacing of the gyroid phase is larger than that of the perforated lamellar structure. The perforated lamellar and gyroid phases coexist for a defined period. The reverse transition from gyroid to lamellae occurs directly, with no transient or metastable intermediates. 相似文献
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V. M. Mastikhin O. B. Lapina V. F. Lyakhova 《Reaction Kinetics and Catalysis Letters》1980,14(3):323-327
Systems V2O5–KHSO4 and V2O5–K2SO4 have been studied by the51V NMR method. The first system demonstrates the same states of vanadium as the previously studied V2O5–K2S2O7, in this system a compound with an equimolar ratio of components has been found. In V2O5–K2SO4 the state of vanadium differs from the above systems and the formation of a compound with V/K=4 is observed.
51V KHSO4–V2O5 K2SO4–V2O5. , K2S2O7–V2O5, . K2SO4–V2O5 V/K4.相似文献
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Horvat A Lyakhova KS Sevink GJ Zvelindovsky AV Magerle R 《The Journal of chemical physics》2004,120(2):1117-1126
The phase behavior of cylinder-forming ABA block copolymers in thin films is modeled in detail using dynamic density functional theory and compared with recent experiments on polystyrene-block-polybutadiene-block-polystyrene triblock copolymers. Deviations from the bulk structure, such as wetting layer, perforated lamella, and lamella, are identified as surface reconstructions. Their stability regions are determined by an interplay between surface fields and confinement effects. Our results give evidence for a general mechanism governing the phase behavior in thin films of modulated phases. 相似文献