The Solid‐Oxide‐Oxygen‐Ion conducting membrane (SOM) technology offers great potential for environment friendly and energy‐efficient extraction of high‐energy‐content metals. This work was performed to demonstrate the technical viability of the SOM technology to produce tantalum metal and tantalum–niobium alloy directly from tantalum oxide and ore concentrates. An electric potential is applied to dissociate the tantalum oxide source, reduce the Ta metal at the cathode, pump the oxygen ions through the membrane (SOM), and oxidize them at the anode. The process can be used to efficiently produce tantalum metal without the expensive pre‐processing of raw materials and generation of harmful byproducts. The work reported in this paper demonstrates that the SOM process can produce high‐purity tantalum metal. The electrochemical behavior of the cell and the method to increase membrane stability are also discussed.

In terms of detection of antibiotics within complex media, the nonspecific adsorption is an enormous challenge and antifouling sensing interfaces capable of reducing the nonspecific adsorption from complex biological samples are highly desirable. In this work, a novel antifouling electrochemical immunosensor was explored based on the self-assembly of two kinds of poly­(N-isopropylacrylamide) microgels on the surface of graphene oxide for sensitive detection of streptomycin (STR). The microgels modified with glycidyl methacrylate (GMA) and zwitterionic liquid 1-propyl-3-vinylimidazole sulfonate (PVIS) were prepared. The microgels with GMA were used by combining specific recognition of anti-STR. The rapid specific binding of antigen and anti-STR resulted in a decrease of current density to generate electrochemical responsive signals. Zwitterionic liquid-modified microgels were used for antifouling, which can form stronger hydration and show excellent antifouling ability. As a result, we achieved efficient and sensitive detection of STR in the complex sample with evidently resisted nonspecific adsorption effect, the wide linear range toward STR was from 0.05 to 100 ng mL–1, with a detection limit down to 1.7 pg mL–1. The immunosensor based on the surface functionalization of microgels showed promising applications for the detection of antibiotics in complex media.

The CaZrO3 complex oxide ceramic was synthesized in the development of the potential refractory for melting of titanium alloy, the crucible ( 40XH40mm) was prepared by the solid sintering of mixture of powder (CaO:ZrO2 =1:1) with a small amount of TiO2 as additive at 1750°C. The melting of TiNi and Ti6Al4V was carried out in the inducting furnace under vacuum or/and Ar atmosphere. The interfacial reaction between the melts of alloys and CaZrO3 refractory was investigated by scanning electron microscope (SEM) with energy dispersive X-ray spectroscopy (EDS). It is found that, the thickness of interfacial reaction layer between the ceramic CaZrO3 and the melt of titanium alloys (TiNi and Ti6Al4V) is approximately 30-300 μm, there are few elements such as Ca, Zr, Ti, and Ni diffused through the interfacial reaction layer. These results may provide the basement to designing a novel refractory for melting of titanium alloys.

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Helicopter tail rotors adopt a segmented driveline connected by flexible couplings, and dry friction dampers to suppress resonance. Modeling for this system can provide a basic foundation for parameter analysis. In this work, the lateral-torsional vibration equation of the shaft with continuous internal damping is established. The static and dynamic effects caused by flexible diaphragm couplings subject to parallel and angular misalignment is derived. A novel dual rub-impact model between the shaft and dry friction damper with multiple stages is proposed. Finally, a model of a helicopter tail rotor driveline incorporating all the above elements is formulated. Numerical simulations are carried out by an improved Adams–Bashforth method following the design flowchart. The dynamics of multiple vibration suppression, and the static and dynamic misalignment are analyzed to illustrate the accuracy and characteristics of the model. The coeffect of the rub impact and the misalignment on shafts and dampers are presented through the results of simulation and experiment. It provides an accurate and comprehensive mathematical model for the helicopter driveline. Response characteristics of multiple damping stages, static and dynamic misalignment, and their interaction are revealed.