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北京石油化工學院2026年研究生招生接收調(diào)劑公告

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本帖產(chǎn)生 1 個翻譯EPI ，點擊這里進行查看

wanghaiju

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[求助] 高分子論文翻譯求助

After the investigation of the double-layer as-received woven fabrics, the absorption potentials of samples of both as-received and heat-treated layer double-layer combinations were examined. The absorption potentials of combinations of PN-H and heat-treated S8 (S8-H) fabrics with as-received ZE8 fabrics at various frequencies are compared in Table 4. It can be observed that a combination of S8-H fabrics had a slightly higher absorption potential than one of PN-H types. As there is little difference in the conductivity of heat-treated S8- and PN-type woven fabrics, the better absorption potential of the S8-type woven fabrics is believed to be a result of its smoother surface, which eliminates internal reflections.
In the final case, double-layer combinations of heat-treated fabrics were assembled. Table 5 lists the absorption potential of all combinations of heat-treated fabrics. The S8-H and ZE8-H combination proved to have the best absorption potential among all samples. In the heat-treated condition, the ZE8 revealed the highest conductivity due to localized oxidation, and combinations containing the ZE8-H fabric as the second layer resulted in better absorption. A double-layer combination of ZE8-H-type woven fabrics did not improve its electromagnetic wave absorption property, as the high conductivity of the combination strengthened reflection loss.
The surface condition of the fabrics was also important in their electromagnetic wave absorption potentials. The S8 and ZE8 samples had a satin weave, and hence their surfaces were smoother than that of the plain type PN. As the smoother surface suppressed multiple reflection losses from the surface of the materials, the surface characteristics of a fabric can also be said to be important for electromagnetic wave absorption. The absorption potentials of double-layer combinations of S8 and ZE8 fabrics are shown in Fig. 8. As-received and S8-H- and ZE8-type combinations revealed similar absorption potentials, which are higher than 90% in the 18.5–26.5 GHz frequency range. This result demonstrates that heat treatment did not necessarily mean an improvement in the absorption potential of SiC-based ceramic woven fabrics, but rather that heat treatment may be used to create woven fabrics with different electrical conductivities. In this regard, with a proper sequence of woven fabrics (low-conductivity layer before high-conductivity layer), better absorption potentials can be achieved. However, if a high electrical conductivity layer is placed in front of a low-conductivity layer, the absorption potential of the combination decreases
(Fig. 8), since a significant portion of the incident electromagnetic waves were reflected from the surface before transmitting through the material. The high absorption potential of the double-layer combinations of SiC-based ceramic woven fabrics in the GHz range renders them useful as electromagnetic wave-absorbing material systems.

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wanghaiju: 金幣+38, 翻譯EPI+1, ★★★★★最佳答案 2014-06-12 12:31:00

研究了雙層收貨狀態(tài)的織物后，檢驗收貨狀態(tài)和經(jīng)熱處理后的雙層組合樣件的吸收能力。PN-H和熱處理后S8（S8的ZE8織物在不同頻率下吸收能力的對比如表4所示。可以發(fā)現(xiàn)S8-H織物的組合有略高于PN-H類型的吸收能力。由于熱處理后S8和PN類型織物的電導率區(qū)別很小，有理由認為S8類型織物較好的吸收能力源于能消除內(nèi)部反射的較平滑表面。
最后一例組合了雙層熱處理后織物。表5列出了各種熱處理后織物組合的吸收能力。S8-H和ZE8-H的組合證實具有所有樣件中最好的吸收能力。熱處理狀態(tài)下，ZE8因局部氧化表現(xiàn)出最高的電導率，將ZE8-H織物作為第2層的組合因此具有更好的吸收能力。雙層ZE8-H類型織物的組合沒有改進電磁波吸收性能，因為組合的高電導率增強了反射損失。
織物的表面狀態(tài)對其電磁波吸收能力也有重要。S8和ZE8樣件使用緞紋編織，因此表面較平紋的PN型更平滑。由于平滑的表面抑制材料表面的多重反射損失，也可以說織物的表面特性對電磁波吸收很重要。S8和ZE8織物雙層組合的吸收能力如圖8所示。收貨狀態(tài)及熱處理后的S8和ZE8型的組合顯示出相似的吸收能力，在18.5-26.5GHz頻率范圍高于90%。結(jié)果顯示，熱處理對基于SiC的陶瓷織物的吸收能力沒有明顯改進，但可用于制作不同電導率的織物。因此，適當?shù)目椢锝M合（低電導率層在高電導率層之前）能產(chǎn)生更好的吸收能力。然而如果高電導率層放在低電導率層之前，組合的吸收能力降低（圖8），因為相當部分的入射電磁波在穿過材料前從表面反射。
基于SiC的陶瓷織物的雙層組合在GHz范圍的高吸收能力使它們成為有用的電磁波吸收材料系統(tǒng)。

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2樓2014-06-12 10:18:13