The molybdenum powder with crystalline icositetrahedron morphology was produced by hydrogen reduction of MoO 3. The particle size and morphology of MoO 3 were specified to control the reaction rate. The phase change and microstructure during the MoO 3 -MoO 2 reduction were highlighted to obtain MoO 2 , which tended to form polyhedral Mo powder. Reduction conditions such as temperature profile, hydrogen dew point, and flow rate were optimized systematically to favor the nucleation and growth of new phases. The molybdenum powder thereof was sintered with conventional method, and the microstructure of the postsinter plate was determined. The density of 10.15 g/cm 3 was achieved. The mechanism of the polyhedral powder formation and the sintering performance of 99 pct theoretical density were discussed.

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In order to drive the development strategy in response to innovate and promote the construction of sponge city in Changde, the green industrial chain model of new biomass material was constructed based on the byproducts of spongy city construction, such as reed and pennisetum were used as substrates. 18 invention patents were created, such as "A herbaceous plant based weatherproof stealth plate and its preparation method". The technical principles based on the series of invention patents were expounded, the innovation of core patent technology was analyzed, some works of patent technology transformation and application were presented, and the technical economic value and application prospect of core patents were discussed. The results show that the new biomass materials, such as 3D printing consumables, outdoor weatherproof materials, absorbing stealth plates and mechanical engineering materials, which are the base material for the construction of the spongy city, have a broad application prospect and great technical and economic value 1 .

Non-orthogonal multiple access (NOMA) collaborative communication is extremely beneficial to the users with poor channel conditions. It is essential to examine the performance of different NOMA users with superior cooperative forwarding protocols. This paper addresses the user cooperative NOMA system where one strong user (U2) assists one weak user (U1) to forward messages, and investigates the outage performance of both users with hybrid decode-and-amplify forwarding (HDAF) protocol. First, we derive the outage probability of U2 and U1 with HDAF. Secondly, we provide the closed-form expression for outage probability of U1 with the incremental hybrid decode-and-amplify forward (IHDAF) protocol at U2, which can further enhance the outage performance of U1 compared with HDAF. Moreover, we also present the system throughput expression and provide deep analysis on the effect of different forwarding protocols. Numerical results and Monte Carlo simulations jointly confirm the correctness of all the analytic derivations. In addition to saving the energy consumption of U2, IHDAF can make U1 achieve superior outage performance to HDAF. However, the system throughput almost overlap for both schemes given a threshold rate pair.