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The experiment was conducted to explore the effect of the metabolites of Lactobacillus plantarum on the growth performance and intestinal health of Yellow-feathered broilers. A total of 828 one-day-old Yellow-feathered broilers were randomly divided into two groups, with six replicates in each group and sixty-nine broilers in each replicate. The broilers in the control group were fed with basal diet, and the experimental group added 300 mg/kg the metabolites of Lactobacillus plantarum into the basal diet. The experiment lasted for 63 days. The results showed that compared to the control group, F/G of Yellow-feathered broilers in 1-21 days of the experimental group was decreased by 1.8% (P<0.05), the gene expression of TNF-α, IL-1β, and IL-6 of jejunum were decreased by 50.5%, 72.6%, and 23.1%, respectively (P<0.05), and the score of dung morphology was decreased by 40.3% (P<0.05). The ADG of Yellow-feathered broilers in 22-63 days, the VH in jejunum and ileum, the VH/CD in ileum, and the microbial community abundance of Butyrate-producing bacteria in the experimental group were increased. The study indicates that the metabolites of Lactobacillus plantarum combined with the basal diet can improve the growth performance and intestinal health, and then improve the economic benefit. [ABSTRACT FROM AUTHOR]

A series of copolymers (P(AA-co-MPC)) with acrylic acid (AA) and 2-methacryloy-loxyethyl phosphorylcholine (MPC) monomers were synthesized via RAFT polymerization. Then the magnetic iron oxide nanoparticles were modified by these synthesized copolymers through chemical coprecipitation method. Copolymers and the nanoparticles were characterized by 1H NMR, FTIR, GPC, TG, TEM, XRD, Zeta potential and particle size analyser, and Squid-VSM magnetic measure system. The results show that the P(AA-co-MPC) with narrow molecular mass distribution is successfully synthesized by RAFT polymerization and the surface of the magnetic iron oxide nanoparticles is modified by these copolymers. The modified magnetic iron oxide nanoparticles by copolymer synthesized with the monomer molar ratio of AA:MPC of 1:1 exhibit the best dispersion, the smallest hydrodynamic particle size (36.54±4.00) nm, the narrowest particle size distribution and the highest Zeta potential (-30.98±1.25) mV. The saturation magnetization is 65.57A·m2·kg-1. The nanoparticles show superparamagnetism, with no residual magnetism and zero coercive force.

Topology optimization is at the phase of structural concept design and the result of it is foundation for succeeding design, therefore, structural topology optimization is more important to engineering design. in this thesis, in order to seek the optimal structure shape of the winch’s mounting bracket of ROV simulator, topology optimization design of it by finite element analysis software ANSYS was carried out. the results show that the topology optimization method is an effective optimization method and indicate that the method is correct and effective, it has a certain engineering application prospect.

A novel bi‐directional circularly polarized (CP) antenna with low profile, real planar configuration and broad axial ratio (AR) bandwidth is presented for S‐band satellite relay communication application. The designed antenna consists of four fan‐shaped patches, a sequentially rotating feed network and ground plane with annular gaps. Four fan‐shaped patches are directly integrated with the feed network on the same FR4 substrate for good impedance matching and compact size. To realize the two‐way radiation characteristics and excellent AR bandwidth, one parasitic annular groove on the ground plane is designed. The sequential rotation feeding network can provide good port characteristics within the available bandwidth and good AR. The properties of designed antenna was tested to validate its simulation. The final prototype is 83 × 83 × 0.8 mm3 in size and it can generate a broad impedance bandwidth for voltage standing wave ratio (VSWR) <2 of 36.6% (2.32–3.36 GHz), 3‐dB AR bandwidth of 21.3% (2.6–3.22 GHz) and gain over 5.4 dB in the bi‐directional direction. The miniaturization, low‐cost and good CP radiation for this proposed antenna make it a better candidate for future applications in the field of spacecraft relay communication. [ABSTRACT FROM AUTHOR]