In this study, graphene oxide (GO) was synthesized by the improved Hummers’ method. The degree of oxidation from graphite (Gi) to GO was determined through interlayer spacing calculated from X–ray diffraction. Besides, the effect of KMnO4: Gi ratios (X1), H2SO4 volume (X2), oxidation temperature (X3), oxidation time of stage 1 (X4), and oxidation time of stage 2 (X5) was screened by the Plackett–Burman model. The simultaneous impact of three factors that influenced the degree of oxidation (X1, X2, and X3) was studied by the Box–Behnken experimental model of response surface methodology to achieve suitable conditions for the GO synthesis process. The characterization of GO product was investigated via the modern analytical methods: X-ray diffraction, Raman spectroscopy, Fourier transform infrared spectroscopy, UV–Vis spectroscopy, field emission scanning electron microscopy, transmission electron microscopy, and atomic force microscopy. Inaddition, the study was also carried out on a pilot scale for orientation in industrial application with the yield of 14 g/batch.

본 연구는 경기도 베이비붐세대와 에코세대의 세대별 주거만족도 영향요인을 분석함으로써, 경기도 세 대별 주거만족도 향상을 위한 정책적 함의를 제시하는 것이 목적이다. 이를 위해서 ‘2020 경기도민 삶의 질 조사’ 자료를 활용하여 이분형 로짓분석을 적용한 실증분석을 진행하였다. 분석결과, 베이비붐세대(고령 세대)가 에코세대(청년세대)보다 주거만족도가 높았으며, 베이비붐세대의 경우 경기북부지역보다 경기남부 지역에서 주거만족도(공간적 분포)가 높았다. 청년세대인 에코세대는 전·월세에 거주하는 경우 주거만족도 가 베이비붐세대보다 높았고, 고령세대인 베이비붐세대는 1인가구일수록 주거만족도가 높았다. 이런 결과 를 봤을 때, 베이비붐세대와 에코세대의 세대별 주거만족도 향상을 위한 정책적 함의는 다음과 같다. 첫째, 베이비붐세대의 경우 1인가구(소형주택) 중심의 주택공급 전략이 필요하다. 둘째, 베이비붐세대의 주거안정 을 위해서는 주택공급의 다양화가 필요하다. 셋째, 에코세대의 주거안정을 위해서는 임대주택 중심의 주택 공급이 필요하다. 넷째, 에코세대를 타깃으로 한 주거비지원과 금융지원이 필요하다. 마지막으로, 에코세대 의 주거만족도 향상을 위해서는 지역별 차별화 전략이 필요하다. 본 연구는 세대별 주택정책 수립을 통해 경기도민의 주거복지를 향상시키는 데 기초자료로 활용될 것으로 기대된다.

본 연구의 목적은 스마트시티 구축의 핵심인 수소연료전지의 활용형태를 분석하고 해결방안을 제시하는 것이다. 수소연료전지를 활용하는 발전소의 경우 간헐성 문제가 없다는 장점 때문에 향후 가장 유망한 사용 형태로 분석됐다. 다만 많은 장점에도 불구하고 폭발 우려와 특정 수소 생산방식의 경우 이산화탄소 발생 문제 등으로 지역주민들의 반발이 지속적 으로 나타나고 있어 이를 해결하는 것이 스마트시티 구축의 주요 관건이 될 것으로 분석된다. 마지막으로 현재의 수소 생산 방식을 분석하고 이에 따른 문제점을 파악하여 스마트시티의 완전한 구축을 위한 해결책을 제시하였다.

본 연구는 식품 영역에서 제품 패키지의 광택이 소비자들이 인식하는 기업 친환경성과 제품 품질에 미치는 영향을 확인하고, 최종적으로 구매의도에 차이를 유발하는지 확인하고자 실시되었다. 실험 참가자들은 패키지에 광택이 도 는 유광 조건과 광택이 없는 무광 조건으로 무선 할당되었으며, 케첩과 감자칩 제품을 보고 기업 친환경성 인식, 품질인식, 구매의도를 묻는 문항들에 응답하였다. 연구 결과, 소비자들은 무광 패키지 제품을 제조한 기업이 유광 패키지 제품을 제조한 기업보다 더 유기농 재료를 사용할 것이며, 더 친환경적일 것이라고 인식하였다. 또한 소비자 들은 기업이 친환경적일 것이라고 인식할수록 제품의 품질을 높게 평가하였으며, 더 높은 구매의도를 보였다. 본 연구는 패키지 광택의 효과를 친환경 식품 영역에서 기업 이미지 인식에까지 확장하였으며, 패키지 광택을 이용한 친환경 마케팅 방식을 제안했다는 점에서 이론적, 실무적 의의를 가진다. 본 연구의 한계, 가능한 향후 연구 방향도 함께 논의하였다.

PURPOSES : In this study, an eco-friendly mastic asphalt backfill material is developed to reduce production and construction temperatures by 40 ℃ compared with those recorded when using conventional hot-mix mastic asphalt backfill materials. METHODS : To reduce the production and construction temperatures, SIS polymer modifiers and gum rosin were selected, and gum rosin-modified SIS materials were applied to the mastic asphalt binder mix design. SIS is less viscous than SBS at high temperatures owing to its thermal characteristics, and incorporating gum rosin into SIS causes the latter to exhibit a loose and soft structure. To improve the performance of the mastic asphalt modified with SIS and gum rosin, three different filler mixes, i.e., 100% PMMA, 50% PMMA and 50% calcium carbonate, and 40% PMMA and 60% calcium carbonate were applied. RESULTS : The rosin-modified SIS reduces the viscosity of the developed mastic asphalt binders. In particular, incorporating 3.7% of gum rosin is beneficial to the mastic binder and does not degrade its low-temperature performance. Similarly, using 100% PMMA as a filler improves the performance but results in workability issues at high temperatures. CONCLUSIONS : Rosin-modified SIS and PMMA are promising alternatives for increasing the workability at high temperatures while maintaining the target performance of grade PG82-22 binders if the appropriate ratio of calcium carbonate is mixed with PMMA and an alternative filler comprising calcium carbonate is used.

돌발성 해충인 매미나방의 방제체계 수립을 위해 시판 유기농업자재 21종에 대한 살충 활성을 실내 검정하였다. 90% 이상의 살충 활성을 보인 유기농업자재 11종을 선발하였으며, 유효성분들을 분석하였다. PLS 제도의 대응하여 본 연구 결과는 돌발성 매미나방의 친환경 방제 및 향후 유기농업자재의 개발에도 활용이 가능할 것으로 생각된다.

The overall process, from the pre-treatment of aluminum substrates to the eco-friendly neutral electroless Ni-P plating process, was observed, compared, and analysed. To remove the surface oxide layer on the aluminum substrate and aid Ni-P plating, a zincation process was carried out. After the second zincation treatment, it was confirmed that a mostly uniform Zn layer was formed and the surface oxide of aluminum was also removed. The Ni-P electroless plating films were formed on the secondary zincated aluminum substrate using electroless plating solutions of pH 4.5 and neutral pH 7.0, respectively, while changing the plating bath temperature. When a neutral pH7.0 electroless solution was used, the Ni-P plating layer was uniformly formed even at the plating bath temperature of 50 oC, and the plating speed was remarkably increased as the bath temperature was increased. On the other hand, when a pH 4.5 Ni-P electroless solution was used, a Ni-P plating film was not formed at a plating bath temperature of 50 oC, and the plating speed was very slow compared to pH 7.0, although plating speed increased with increasing bath temperature. In the P contents, the P concentration of the neutral pH 7.0 Ni-P electroless plating layer was reduced by ~ 42.3 % compared to pH 4.5. Structurally, all of the Ni-P electroless plating layers formed in the pH 4.5 solution and the neutral (pH 7.0) solution had an amorphous crystal structure, as a Ni-P compound, regardless of the plating bath temperature.

In this paper, cycle performance analysis of two-stage compression two-stage expansion refrigeration system using eco-friendly refrigerants is presented to offer the basic design data for the operating parameters of the system. Eco-friendly refrigerant R600a(Isobutane) for freon refrigerant R22 were used working fluids in this study. The coefficient of performance(COP) of R600a is about 5% greater than that of R22 two-stage compression refrigeration system in the range of evaporation temperature –30℃∼-60℃. The coefficient of performance of two-stage compression and two-stage expansion refrigeration system decreases with the increasing condensation temperature and superheating degree but increases with the increasing evaporation temperature, subcooling degree and mass flow rate ration of intercooler.

In the 21st century, the demand for eco-friendly leather, such as eco-leather and vegan leather, is steadily increasing. This study examines the influence of eco-friendliness on consumers’ purchasing intentions and the possibility of eco-friendly changes in the fashion accessory market, which is dominated by leather material and leather substitutes. This study administered a questionnaire survey to 227 males and females between 20 and 60 years of age in Korea. With a 5-point Likert scale, data were collected on evaluation criteria when purchasing shoes and bags and purchasing intention of various leather substitute materials according to the democratic variables. The eco-friendliness attitude was divided into eco-consciousness and green behavior. As the eco-friendly attitude increased, most purchasing standards increased, but the purchasing criteria, such as trends, brands, and prices, did not correlate with the eco-friendly attitude. The eco-consciousness of a consumer had a high correlation with the design evaluation criteria, while the green behavior of the consumer aligned with durability and comfort criteria when purchasing a bag. There was a preference for recycled leather, vegetable leather, synthetic leather, and chemical leather, and the fabric type was ranked as natural fiber, biodegradable fiber, and synthetic fiber. Consumers with both green behavior and eco-consciousness are more likely to purchase biodegradable textiles and vegetable leather for the material of shoes and bags.

Various eco-friendly seed disinfection technologies have been developed due to the increase in the global demand for organic food. In order to produce sustainable and eco-friendly agricultural products in Korea, seed disinfection technologies for the production of wholesome seedlings have been researched in diverse ways compared to how they were examined in advanced countries. Both domestically and internationally, the eco-friendly seed disinfection technologies to secure the horticultural crops have been treated by biological or physical methods, such as hot water treatment with ultrasonic disinfection technology, or applying organic agricultural materials like organic acids in plant extracts. However, from a practical perspective, various applied technologies can be implemented in farm fields to disinfect significant agricultural crops, such as lettuce, Chinese cabbage, radish, watermelon, cucumber, paprika, red pepper, ginger, ginseng, and sesame seeds.