International Journal of Modern Physics B

This paper presents an analysis of interactions between a pair of Stone–Wales (SW) defects in a single-walled carbon nanotube (SWCNT) that has been subjected to an external torque. Defect pairs, representing the different combinations of SW defect of A (SW-A) and B (SW-B) modes, were incorporated in SWCNT models of different chirality and diameter and solved using molecular mechanics. Defect–defect interaction was investigated by evaluating the C–C steric interactions in the defect that possesses the highest potential energy, E, as a function of inter-defect distance, D. This study reveals that the deformation of the C–C bond is attributed to bond stretching and bending. In the SW-B defects, there is an additional contributor arising from the dihedral angular deformation. The magnitude of E depends on the type of defect but the profile of the E versus D curve depends on the orientation of the defects. The largest indifference length, D₀, beyond which two defects cease to interact, is approximately 30 Å. When the angular displacement of the tube increases two-fold, E increases, but the profile of the E versus D curve is not affected. The sense of rotation affects the magnitude of E but not the profile of the E versus D curve.

A new magnetorheological (MR) fluid was synthesized by dispersing Fe₈₄Nb₃V₄B₉ nanocrystalline powders in a nonvolatile ionic liquid (N,N-diethyl-N-methyl-N-(2-methoxyethyl) ammonium tetrafluoroborate), which is stable from 282K to 573K. The structure, morphology, and magnetization of Fe₈₄Nb₃V₄B₉ nanocrystalline powders prepared by mechanical alloying were analyzed by using an X-ray diffractometer (XRD), a vibrating sample magnetometer (VSM), and a scanning electron microscopy (SEM), respectively. The magnetic clusters of the synthesized MR fluid were observed by using a digital microscope, and its MR properties were measured by using a cone-plate type viscometer. The experimental results showed that Fe₈₄Nb₃V₄B₉ nanocrystalline powders with an average grain size of 10–20 nm can be prepared by mechanical alloying. The MR fluid is magnetic-field-responsive, behaves like non-Newtonian fluids, and its magnetorheological properties are influenced by the applied magnetic flux density and the width of magnetic clusters.

The high-pressure induced structural phase transitions and pressure induced elastic and anharmonic behavior of boron compounds viz. BN, BP, and BAs have been investigated using an inter-ionic potential approach based on charge transfer effect. These compounds go to NaCl phase (B1) under pressure from zinc blende phase (B3). The variations of second-order elastic constants and their combinations follow a systematic trend with pressure, identical to that observed in other compounds of zinc blende structure family. Shear stiffness constants decrease with increasing pressure up to phase transition pressure. The bulk moduli of these compounds are in reasonably good agreement with other theoretical and experimental data. The values of phase transition pressure of these compounds obtained by using the present approach are also in good agreement with those predicted by using the pseudo potential approach. The present approach has also succeeded in predicting the Born and relative stability criterion for stable zinc blende phase of these compounds. We also present a set of third-order elastic constants and pressure derivatives of second-order elastic constants for boron compounds.

Due to the high cost of the qubit generating device (QGD) (the single photon source), QGD may not be available at the same time in both communicating parties (Alice and Bob) who have to execute the quantum bit string commitment (QBSC) protocol for some application environments. All the existing QBSC protocols allow one-way commitment i.e., only the party (Bob) who possesses the QGD is allowed to commit a bit string to Alice who does not have the QGD, but not the other way around. However, what happens if Alice, who does not have the QGD, is required to commit a bit string to Bob? The current QBSC protocols fail to provide a solution in this case. Therefore, the purpose of this paper is to allow Alice, who is not equipped with the QGD, to commit a bit string to Bob who has the QGD. With our proposed protocol, together with previously proposed QBSC protocols, Alice and Bob can perform two-way commitment, even though Bob is the only party who is equipped with the QGD.

We studied the structure and electronic properties of Al₇OH clusters using density functional theory with generalized gradient approximation. OH prefers to the ontop site of Al atoms, and the hollow form is not stable. The Al₇ moieties can keep their structures in ontop form Al₇OH cluster, while it dramatically changes for bridge form ones. The binding strength between Al₇ and OH are much larger than that of Al₇I and Al₇H. The bonding characteristic of Al₇–OH is mainly ionic according to the population analysis. Large binding energy, HOMO–LUMO gap, and high ionization potential imply that Al₇OH cluster is physically high and chemically stable.

An amorphous/nanocrystalline 50Ni–50Ti powder was produced from elemental Ti and Ni powders by solid state synthesis utilizing low energy mechanical alloying with times up to 100 h. The morphology, microstructure, and phase composition of the milling products were evaluated by using scanning electron microscopy and X-ray diffraction analysis. The results indicated that there was no chemical reaction between the elements during the milling process, which led to the direct formation of an amorphous/nanocrystalline structure without any intermediate phase (intermetallic and/or solid solution phase) formation. It seems that the second kind of amorphization process proposed by Weeber and Bakker is governed. It was shown that the formation of amorphous phase was started after 80 h and developed during the milling for 100 h.

By virtue of the entangled state representation, we show that the quantum teleportated state in Bob, after Alice makes an Einstein–Podolsky–Rosen measurement and Bob makes an appropriate unitary transformation on hearing Alice's measurement result via a classical channel, is described by

With the effects of Dzialoshinski–Moriya interaction and external magnetic field, the entanglement transfer has been investigated in a parallel spin-chain system. Our results imply that the perfect transfer can be realized at some special times, and the transfer time can be greatly condensed with the rising of the spin-orbit coupling strength. The entanglement sudden death phenomenon is sensitive to the initial condition. In addition, due to the application of magnetic field on the channel spins, the reliability and efficiency of the transmission are greatly challenged.

Flower-type ZnO nanorods were synthesized by two-step low temperature solution growth and dye-sensitized with phenosafranine for the first time. The scanning electron microscope result shows that the diameter and the length of a single rod of the flower-type nanostructures depend on the method of synthesis. Optical absorption analysis shows a visible absorption at 517 nm, which was otherwise absent in nano ZnO. The photoluminescence spectra of ZnO and dye-sensitized ZnO nano flowers were also analyzed.

In this paper, a fractional-order hyperchaotic system evolved from Liu system is proposed. Based on the theory of fractional calculus, a novel circuit diagram is designed for hardware implementation of the fractional-order hyperchaotic Liu system. Furthermore, implementation results reveal that hyperchaos can be generated in the hyperchaotic Liu system with the system order as low as 3.6 and numerical analysis results demonstrate that the lowest order of the fractional-order Liu system is 0.4.

In this journal, Gerhard Gerlich and Ralf D. Tscheuschner claim to have falsified the existence of an atmospheric greenhouse effect.¹ Here, we show that their methods, logic, and conclusions are in error. Their most significant errors include trying to apply the Clausius statement of the Second Law of Thermodynamics to only one side of a heat transfer process rather than the entire process, and systematically ignoring most non-radiative heat flows applicable to the Earth's surface and atmosphere. They claim that radiative heat transfer from a colder atmosphere to a warmer surface is forbidden, ignoring the larger transfer in the other direction which makes the complete process allowed. Further, by ignoring heat capacity and non-radiative heat flows, they claim that radiative balance requires that the surface cool by 100 K or more at night, an obvious absurdity induced by an unphysical assumption. This comment concentrates on these two major points, while also taking note of some of Gerlich and Tscheuschner's other errors and misunderstandings.

It is shown that the notorious claim by Halpern et al. recently repeated in their comment that the method, logic, and conclusions of our "Falsification Of The CO₂ Greenhouse Effects Within The Frame Of Physics" would be in error has no foundation. Since Halpern et al. communicate our arguments incorrectly, their comment is scientifically vacuous. In particular, it is not true that we are "trying to apply the Clausius statement of the Second Law of Thermodynamics to only one side of a heat transfer process rather than the entire process" and that we are "systematically ignoring most non-radiative heat flows applicable to Earth's surface and atmosphere". Rather, our falsification paper discusses the violation of fundamental physical and mathematical principles in 14 examples of common pseudo-derivations of fictitious greenhouse effects that are all based on simplistic pictures of radiative transfer and their obscure relation to thermodynamics, including but not limited to those descriptions (a) that define a "Perpetuum Mobile Of The 2nd Kind", (b) that rely on incorrectly calculated averages of global temperatures, (c) that refer to incorrectly normalized spectra of electromagnetic radiation. Halpern et al. completely missed an exceptional chance to formulate a scientifically well-founded antithesis. They do not even define a greenhouse effect that they wish to defend. We take the opportunity to clarify some misunderstandings, which are communicated in the current discussion on the non-measurable, i.e., physically non-existing influence of the trace gas CO₂ on the climates of the Earth.