To improve the flame retardancy and mechanical properties of epoxy (EP), a novel intercalated layered double hydroxides (ILDHs) were synthesized by a solution intercalation method using ammonium alcohol polyvinyl phosphate as intercalator. The ILDHs were examined by X-ray diffraction, Fourier transform infrared spectroscopy (FTIR), energy-dispersive spectrometry and scanning electron microscopy (SEM). The conditions for synthesis of ILDHs have been optimized. Thermogravimetric analysis indicated a good char-forming property of ILDHs. The flame retardancy of epoxy was improved by adding ILDHs. The EP composites containing 30-40 mass% ILDHs passed UL-94V-0 rating. Tensile strength was also enhanced by adding 30-40 mass% ILDHs, which was attributed to the involvement of physical cross-linking network among layered particles and polymer chains. The morphology and structures of residues generated during LOI test were investigated by SEM and FTIR to support a fundamental analysis for the mechanism of char formation. SEM observations of residues of the ILDHs/EP confirmed the formation of an incompact charred layer during combustion, which could inhibit the transmission of heat and mass during combustion. It may be inferred that ILDHs acted as a catalyst for esterification, dehydration and compact char formation of EP system.

The purpose of this study was to develop a quantitative method to acquire and analyze the transverse relaxation time (T2 relaxation) of the magnetic resonance imaging of in-vivo knee joint articular cartilage. To reveal the practical significance of this research, participants who underwent weight-bearing cross-country running were assessed by MR T2 imaging and knee functional test. As a result, temporary changes in the cartilage relaxation time at regions of interest were observed shortly post the running (P < 0.05), accompanying with EMG signal monitored in muscles around knee. This study shows the potentials of utilizing quantitative MRI T2 imaging technique as a non-invasive approach to detect the knee articular cartilage loading and stress, which is important for earlier prevention and intervention of cartilage lesions.

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The fluid-driven clamping devices extensively used in the manufacturing industry nowadays are unable to adapt to the development requirements for green manufacturing technology owing to their low energy utilization, severe problems of noise and environment pollution. This article describes a clamping technology sparing the need of hydraulic pump and air compressor. It causes the thermal sensitive material to quickly expand or shrink linearly with the help of semiconductor heating/refrigeration conversion technology; then with the area effect stroke amplifier, the linear extension generated by the material is amplified around 100 times, and is output and passed to the clamping element in a linear motion manner to clamp the workpiece. This clamping device is an intelligent controlled electromechanical-hydraulic integrated system, featuring high energy utilization, extra low noise and fluid leakage etc.

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