Thermal entanglement in molecular spin rings

The thermal entanglement in the triangular molecular spin ring with Dzyaloshinskii-Moriya interaction is studied. The concurrences of arbitrary two spins of the triangular molecular spin ring for various cases are evaluated. The tendency of the concurrence with Dzyaloshinskii-Moriya interaction and temperature is analysed and discussed. We note that the concurrence arrives at its maximum in the regime with the large Dzyaloshinskii-Moriya interaction and low temperature, and gradually decreases to zero with the increase of temperature. The concurrence has different features for the ferromagnetic and antiferromagnetic cases. For completeness, we also numerically calculate the concurrence of spin rings with N 〉 3 spins and analyse their behaviours.

Spin transport in a chain of polygonal quantum rings with Dresselhaus spin-orbit coupling

Using a transfer matrix method, we investigate spin transport through a chain of polygonal rings with Dresselhaus spin-orbit coupling（DSOC）. The spin conductance is dependent on the number of sides in the polygons. When DSOC is considered in a chain which also has Rashba spin-orbit coupling（RSOC） of the same magnitude, the total conductance is the same as that for the same chain with no SOC. However, when the two types of SOC have different values, there results a unique anisotropic conductance.

Study on Properties of Jute Fibres Spun on Ring Spinning System

Jute fibre properties,viz. linear density,mechanical properties,and fibre staple length were analyzed in this paper. Morphology,lignin content,and composition analysis for jute fibres were investigated in order to give further understanding of the fibre properties changing during the chemical treatment and yarn producing processes. The results show that jute properties are greatly changed during the processes of chemical treatment,breaking carding,and finisher carding,whereas slight changes can be found in the processes of drawing,roving,and spinning.

Analysis and Discussion of Fiber Motion in the Spinning Triangle of Ring Spinning

In order to analyze the effect of the spinning triangle on yarn structure,a shape model of the spinning triangle is established.The fiber motion in the spinning triangle can be divided into three stages,and the relationship between yarn structure and fiber duration as well as the force acting on the fibers in the three stages is analyzed.The fiber elongation in different location of the spinning triangle is variational.The difference is that the elongation of fiber in the middle spinning triangle is bigger than that in the edge of it and the difference will be amplified with the increase of spinning triangle width,which has an effect on the characteristic of yarns structure.Research results for further study on compact yarn structure and improving spinning frame structure provide theory basis.

Rieter Presents A New Ring Spinning Machine at the ITMA ASIA in Shanghai

On their Stand B03in Hall W2at the ITMA ASIA+CITME2010in Shanghai,Rieter will present the new G32ring spinning

Global entanglement in ground state of {Cu_3} single-molecular magnet with magnetic field

We investigate global entanglement in the ground state of single-molecular magnet Na9[Cu3Na3（H2O）9（α- AsW9O33）2]-26H2O with an external magnetic field. The concurrence, tangle, and measure function Q, which characterize the pairwise entanglement, 3-party entanglement and total entanglement, respectively, are calculated numerically at zero temperature. The results show that the magnitude and direction of the applied magnetic field play a significant role in the properties of three kinds of entanglement measures. We give a physical interpretation of the variation of the global entanglement with the magnetic field. Finally, the phase diagram of the global entanglement characterized by the critical magnetic fields is presented.

Exact solution of a topological spin ring with an impurity

The spin-1/2 Heisenberg chain coupled to a spin-S impurity moment with anti-periodic boundary condition is studied via the off-diagonal Bethe ansatz method.The twisted boundary breaks the U(1)symmetry of the system,which leads to that the spin ring with impurity can not be solved by the conventional Bethe ansatz methods.By combining the properties of the R-matrix,the transfer matrix,and the quantum determinant,we derive the T–Q relation and the corresponding Bethe ansatz equations.The residual magnetizations of the ground states and the impurity specific heat are investigated.It is found that the residual magnetizations in this model strongly depend on the constraint of the topological boundary condition,the inhomogeneity of the impurity comparing with the hosts could depress the impurity specific heat in the thermodynamic limit.This method can be expand to other integrable impurity models without U(1)symmetry.