This paper presents a multidiscipline coupled-field analysis method to study the temperature distribution of an automotive magnetorheological brake with double coils placed on side housing. First, a new apparent viscosity definition was employed to connect the communication of magnetic field, fluid dynamics, and temperature field. Then, the dynamic model of the brake was established to evaluated the rotation law of the brake disk and the total brake time. At last, multi-physics modeling was established with sequencetial coupling methods, which were based on the Maxwell equations, Naiver-Stokes equations and conjugate heat transfer equations. The results indicate that the overall temperature distribution of the MR brake is relatively uniform at a zero magnetic field during the steady state, and the maximum temperature difference is about 9.7°C. During braking process, the temperature variation regularity for radial and axial points is basically the similar, and the maximum temperature appears in the axial working gap, the maximum value is 113°C which is less than the maximum allowable working temperature of the chosen MR fluid. The results can be taken as reference to the design of the MR brake.

A new dissymmetrical oxamidate ligand has been used to construct a metal-organic network. Using this ligand, a novel coordination polymer, namely {[Cu(obea)]2Cu・CH3OH・H2O}n (1) [H3obea = N1-(2-carboxyphenyl)-N2-(2-hydroxyethyl)oxalamide] has been synthesized and characterized by single-crystal X-ray analysis. The structure of complex 1 consists of neutral trinuclear complex units. Through syn-anti carboxylate bridges, the complex features a 2D structure with a helical substructure. Its magnetic properties have been investigated.

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Borehole-wall collapse mostly occurs in fractured-rock layers during geological and oil drilling. Steel-casing installation，though with high cost and low efficiency，is currently one of the most fundamental methods for mending broken bore-hole walls. Manufactured casing formed by hot melting，however，provides us an alternative. In order to enhance its qualities，like strength and the capacity of resisting corrosion，of the material，we added bentonite as additive to explore some certain links between properties such as density，porosity, abrasion resistance and different sintering temperatures as well as soaking time.

Transformation of the microstructure of molybdenum disilicide heating unit in nitrogen atmosphere at 1700°C was investigated by XRD, SEM and EDS. The results showed that MoSi2 was transformed to polyhedral Si3N4 crystals groups distributed across in the matrix with irregular geometry Mo5Si3 and Mo3Si crystals, and the Si3N4 crystal groups were dense areas, while the Mo5Si3 and Mo3Si groups were loose areas after being heated in nitrogen atmosphere at 1700°C for 3h. The thickness of conversion zone of MoSi2 matrix was about 30μm and the loose Mo5Si3 and Mo3Si areas can damage the dense structure of MoSi2 matrix.