RESUMEN
In this paper, the SiCN(Ni)/BN ceramic with excellent electromagnetic wave (EMW) absorption performance was successfully prepared. The Ni and Ni3Si were in situ formed by the introduction of nickel acetylacetonate (NA), which effectively improved the impedance matching performance of SiCN(Ni)/BN ceramics. The EMW absorption properties of the SiCN(Ni)/BN ceramics showed a trend of first increasing and then decreasing with the increase in content of NA. When the NA content reached 7 wt%, the impedance matching range of SiCN-7 was optimal. The minimum reflection loss (RLmin) of SiCN-7 reached -53.47 dB at 4.2 mm and the effective absorption bandwidth (EAB) was 2.32 GHz at 3.48 mm. Through the analysis of electrical conductivity, it was found that the proportion of polarization loss in dielectric loss was more than 99%. It is worth noting that the radar cross section (RCS) value of SiCN-7 absorber was lower than that of the perfect electrical conductor (PEC) plate in the range of -90-90°, and showed a larger coverage angle, indicating that it possessed a good practical application prospect in the field of electromagnetic wave absorption.
RESUMEN
OBJECTIVE: To explore the laparoscopic surgery efficacy for the treatment of liver trauma. METHODS: From January 2009 to March 2014. 32 patients were received laparoscopic surgery for liver trauma treated in our hospital. There were 21 males and 11 females with an average age of 33.7 years old. Among the group, 23 cases were closed abdominal injury, 9 cases were open injury. 7 cases were Combined organ injuries. The patients' injuries arose from various causes, 13 due to falling, 10 due to be crushed, and 9 due to be cut. RESULTS: 32 patients were treated with laparoscopy completely. According Moore Classification standards. 2 cases were type I, 7 cases type II, 19 cases type III, 4 case type IV. 32 cases underwent electric coagulation, laparoscopic fibrin glue and soluble hemostatic gauze packing (n = 5), sutures to the broken liver (n = 20), debridement partial hepatectomy (n = 7). The patients combined with other organ injury were treated with laparoscope simultaneously. The operative duration time were 85 (30-210) mins. There was no postoperative death. CONCLUSION: Correct selection of indication and a deft laparoscopic liver resection help guarantee the laparoscopic surgery to be applicable way in treatment liver trauma.
