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Nanoscale metal oxides based binder-free electrodes have application prospects in the energy storage field. In this work, Fe2O3 nanosheets composited with carbon matrix were prepared via the electr...

One-dimensional (1D) transition metal oxides materials with unique mesoporous structure have potential applications in the energy conversion and storage field. In this work, 1D mesoporous Fe2O3 nanowires growth on strain steel substrate were prepared through a two-step solution method and used as anode materials for lithium batteries. The electrode delivers discharge capacity of 1460 mAh·g−1 at 100 mA g−1 density after 200 cycles. Furthermore, the electrode exhibited outstanding rate capability and its reversible capacity reaches to 700 mAh·g−1 at 800 mA g−1 density. Such excellent cycle performance may ascribe to the capacitive effect caused by the unique mesoporous nanowire structure. This work may provide a facile and efficient method for the preparation of high performance Fe2O3 anode materials.

This paper presented a regularization approach to construct Lyapunov function for judging the stability of non-linear systems. The gradient function is derived primarily from the state equation of the non-linear system. The gradient function coefficients is determined such that a negative positive derivative function of Lyapunov function is derived. Then a Lyapunov function is solved by the line integral to the gradient function. And then judging whether the solved Lyapunov function is positive definite. Application examples indicate there can construct a Lyapunov function for asymptotically stable non-linear system. This approach provides another way to judge the stability of some non-linear time-invariant systems.

This paper aims at exploring the modal analysis approach of a motion control system. Based on the inverse Laplace transformation, the step response of a control system is derived. Then this response is associated with the modal analyses in state space theory. And then the motion mode of a control system is analyzed with the modal analysis method. Application example indicates that this approach can be used to analyze the high-order control system successfully. This facilitates the motion mode analyses of high-order control system very much.

This paper aims at proving the complex impedance of the inductor and capacitor elements and applying the proved complex impedance concept to directly obtain the transfer function model of the complicated circuit network. Based on Laplace Transformation method, the complex impedances of the inductor and capacitor elements are proved. Using the proved complex impedances and the equivalent complex impedances in series and in parallel, both the transfer functions of the passive and active circuit networks are modeled. This facilitates the transfer function modeling of the complicated circuit network very much.

This paper aims at directly modeling the transfer functions of mass-spring-damper systems. Using complex stiffness of mass, spring, and damper elements and equivalent complex stiffness of these elements in series and/or in parallel, the transfer functions of the mass-spring-damper systems are modeled quickly. This is very convenient to the modeling of the complicated mechanical systems.

This paper models the electromagnetic force/torque of a long-stroke magnetically levitated planar motor. Based on the Lorenz force volume integral law and the force/torque superposition principle of rigid body, the electromagnetic force/torque is modeled. Experimenting results indicate the model is consistent with the measured results in sine distribution and sine period, and the errors between the model values and the measured values originate mainly from the measurement system. So this model represents analytically the electromagnetic forces and torques of the planar motor and it can be used to commutate and control the planar motor.

To explore the correlation of lumbar stenosis and knee osteoarthritis by establishing a rabbit lumbar spinal stenosis model and observing the hind limb movement function and pathological change of articular cartilage of knee joint.A total of 36 healthy adult rabbits were randomly divided into model group and control group. In the model group, spinal canal was filled with bone pieces to make lumbar spinal stenosis; in the control group, sham operation was performed and materials were inserted into spinal canal. Movement function was evaluated by Tarlov method and pathological features were observed by Mankin's scores under light microscope at 4, 8 and 12 weeks.Early degenerative changes of knee cartilage were observed in the model group at 4 and 8 weeks post-operation. There were synovial hyperemia and hyperplasia, increased synovial fluid effusion and lightly-stained cartilage. The Mankin score was 3.3 - 4.5 and Tarlov score 3 - 4. Intermediate stage changes of osteoarthritis were found in the model group at 12 weeks post-operation, showing synovial hyperplasia, decreased synovial fluid, fissure in cartilage surface, tangled cartilage cells and unevenly stained matrix. The Mankins score was 7 - 9 and Tarlov score 2 - 3. Most of articular cartilage was normal in the control group with Mankin score of 0 - 1 and Tarlov score of 4.Lumbar stenosis may be correlated with knee joint degeneration.