Despite having a low electrical conductivity, graphene oxide (GO) is used as an anode material in lithium-ion batteries (LIBs) owing its good processability in large quantities. GO is reduced by chemical or thermal treatments to enhance its electrical conductivity. In this study, high-performance GO anodes with polydopamine (PDA) and polyethylenimine (PEI) as binders were fabricated. Gamma (γ)-ray irradiation was applied to the GO–PDA–PEI hybrid sheets to covalently cross-link the GO sheets and binders with an amide bond. The covalent crosslinking was confirmed by Fourier-transform infrared spectroscopy analysis. Further, X-ray photoelectron spectroscopy results showed that γ-ray irradiation produced a reduced GO sheet, which resulted in an increase in the electrical conductivity by 30%. By characterizing the electrochemical properties, we found that the γ-ray irradiation facilitates the stability and increases the charge/discharge capacity by crosslinking GO and PDA–PEI binders and reducing the GO sheets.

본 연구는 스마트건설 지원을 위한 드론 활용의 활성화를 위해 RTK 드론 기반의 항공측량 정밀도를 분석하고자 GPS만을 사용하는 방식, GCP를 설치하는 방식, RTK 드론을 이용한 방식의 정사영상의 위치정확도를 분석하였고 사업의 목적과 대상지의 형태에 따른 드론 활용의 기준을 제시하였다. 또한 상용 드론을 이용한 체적기반의 토공량 산출을 2.5D 환경에서 산출하여 기존 방법과 비교해서 드론영상을 효율적으로 활용할 수 있는 방법을 제시하였다. 본 연구로 대규모 건설현장의 작업효율 및 드론 활성화가 기대된다.

Bisphenol A (BPA), a representative endocrine disrupting chemicals, has adverse effects on growth, development and reproduction in aquatic organisms. The object of this study was to investigate the modulation of antioxidant enzyme - coding genes using quantitative real time RT - PCR (qRT - PCR), enzyme activity and total protein content, to understand oxidative stress responses after exposure to BPA for 48 h in brackish water flea Diaphanosoma celebensis. The BPA (3 mg L-1) significantly upregulated the expression of Cu / Zn - SOD, Mn-SOD, and catalase (CAT ) mRNA. Three GST isoforms (GST-kappa, GST-mu, and GST-theta) mRNA levels significantly increased at the rate of 0.12 mg L-1 of BPA. In particular, GST-mu showed the highest expression level, indicating its key role in antioxidant response to BPA. SOD activity was induced with a concentration - dependent manner, and total protein contents was reduced. These findings indicate that BPA can induce oxidative stress in this species, and these antioxidants may be involved in cellular protection against BPA exposure. This study will provide a better understanding of molecular mode of action of BPA toxicity in aquatic organisms.