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This article established a 3-D transient melting calculation model of the electromagnetic rail launcher (EMRL), considering the combined effects of electromagnetic fields, structural fields, heat transfer, and armature motion. To verify the accuracy of the multiphysics field coupling model, an experiment platform of EMRL that is capable of retrieving the launched armature is set up. Compared with the armature surface profiles obtained from the experiment, the simulation model describes the locations of deeper melting accurately but is not precise enough for the shallower melting. Through analyzing the evolution of the melting region, it is found that the deepest crater forms at the point where the armature begins to melt. Analysis of the heat sources shows that contact resistance heat and body heat are two critical factors in the process of armature melting. Despite the high power of the frictional heat, there is no melting in the region where it exists. It is proven that the proposed model can predict the melting performance of the armature.

Muzzle voltage is often used to describe the contact state of armature–rail interface, which can be divided into induced voltage, contact resistance, and armature resistance. In this article, the calculation method of mutual inductance coefficient and induced voltage is proposed based on the simplified 2-D model, and the calculation is carried out based on the current waveform in the experiment. A comparison between theoretical calculations and experimental results shows that the muzzle voltage of the conventional railgun is much greater than the induced voltage. It is generally believed that the armature resistance is negligible, so the contact resistance is the main component of the muzzle voltage. Then, it is feasible to judge the contact state of the armature–rail interface by the change of the muzzle voltage. In contrast, the muzzle voltage of the augmented railgun is mainly from the induced voltage, and it is not easy to determine whether a transition has occurred. We need other methods to determine whether the augmented railgun is fired successfully or not.

In order to effectively remove grease for the detection of sulfonamides, a non-toxic and low-cost hierarchical porous zirconia material was synthesized using the dual template method. The lipid impurities in an animal-derived food matrix can be absorbed by hierarchical zirconia. A ZrO2prepolymer was synthesized by mixing amphiphilic triblock copolymer poly(ethylene glycol)-block-poly(propylene glycol)-block-poly(ethylene glycol) (P123) with tannin extract as the double template and Zr(SO4)2as the metal source. After aging, drying and calcination at high temperature, the prepolymer transforms into a hierarchical porous structure. The synthesized materials were characterized using SEM, XRD, FT-IR, and BET. The results show that the material has an abundant pore structure and hierarchical pore structure. The adsorption conditions were optimized. The hierarchical porous ZrO2synthesized by this method is relatively uniform, and is characterized by large specific surface area as well as high lipid impurity adsorption capacity. Through the optimization experiment of adsorption conditions, we found that hierarchical porous ZrO2can reach the maximum adsorption capacity in 60 min under weak acidic conditions. The samples are used for actual sample testing such as HPLC of sulfadiazine (SD), sulfamethazine (SM2), sulfamethoxydiazine (SMD), sulfamethoxazole (SIZ) and sulfadimethoxine (SDM), and the recovery experiment of sulfonamides in chicken was carried out. The recoveries were 80.9–97.6% and the detection limit was 3.8–17.6 μg L−1. This work provides a new strategy for oil removal using hierarchical porous materials.

Leptin (LEP) is reported to play important roles in controlling energy balance in vertebrates, including birds. However, it remains an open question whether an authentic “LEPgene” exists and functions in birds. Here, we identified and characterized a LEPgene (zebra finch LEP[zbLEP]) encoding a 172-amino acid precursor in zebra finches. Despite zbLEP showing limited amino acid sequence identity (26%–29%) to human and mouse LEPs, synteny analysis proved that zbLEPis orthologous to mammalian LEP. Using a pAH32 luciferase reporter system and Western blot analysis, we demonstrated that the recombinant zbLEP protein could potently activate finch and chicken LEP receptors (zbLEPR; cLEPR) expressed in human embryonic kidney 293 cells and enhance signal transducer and activator of transcription 3 phosphorylation, further indicating that zbLEP is a functional ligand for avian LEPRs. Interestingly, quantitative real-time RT-PCR revealed that zbLEPmRNA is expressed nearly exclusively in the pituitary and various brain regions but undetectable in adipose tissue and liver, whereas zbLEPRmRNA is widely expressed in adult finch tissues examined with abundant expression noted in pituitary, implying that unlike mammalian LEP, finch LEP may not act as an adipocyte-derived signal to control energy balance. As in finches, a LEPhighly homologous to zbLEPwas also identified in budgerigar genome. Strikingly, finch and budgerigar LEPs show little homology with chicken LEP (cLEP) previously reported, suggesting that the so-called cLEP is incorrect. Collectively, our data provide convincing evidence for the existence of an authentic functional LEP in avian species and suggest an important role of brain- and pituitary-derived LEP played in vertebrates.