|
|
다운로드
(기관인증 필요)
|
|
초록보기
본 보고서는 국가회계기준 개선 프로젝트를 2020년부터 시행하기 위한 준비단계로 프로젝트 제안, 진행, 보고서 작성, 의견 수렴 및 개선안 마련 등 진행절차를 수립하고 각 절차별 전략과 산출물 등을 제시하였다. 각 과제별로 프로젝트 개요, 팀 보고서, 쟁점보고서, 자문보고서 및 제안초안으로 구분하여 진행절차와 운영방안을 제시하였으며, 2019년 시범수행 결과를 바탕으로 2020년 진행과제로 융자 회계처리지침 개정, 재무보고 개선 및 연금 회계처리 개선을 선정하여 과제별 이슈와 함께 프로젝트 개요서를 첨부하였다. 이와 더불어 2020년 이후 예정되어 있는 진행과제를 간략히 소개하였으며, 이는 지속적인 관계기관 및 외부 의견수렴 등을 통해 개선해나갈 예정이다. 국가회계재정통계 센터에서는 본 보고서를 통해 국가회계기준 개선 절차의 체계를 확립할 수 있는 토대를 마련하고자 한다.
|
|
|
다운로드
(기관인증 필요)
|
|
초록보기
Renewable energy provides an intermittent operation environment, so the electrodes of water electrolysis need high durability and long life time for hydrogen production. In this study, 3-electrode system prepared using NiZnFe electrodes plated under two different conditions and the degradation characteristics of the electrode were confirmed by the cathodic potential on/off test in the hydrogen generation evolution reaction. The on/off test was operated about 150 cycles in the range of about -1.3 V to 0 V and reverse current occurred in the off step. As a result of LSV(Linear sweep voltammetry) for electrochemical analysis, the HER activity of 80 mA/㎠, 2000 s electrode and 320 mA/㎠, 2000 s electrode decreased about 10% and 15%, respectively. This results show that Zn dissolution and reverse current are related to deactivation. 320 mA/㎠, 600 s electrode is relatively less deactivation and less peeling off coating layer than 80 mA/㎠, 2000 s electrode.
|
|
|
다운로드
(기관인증 필요)
|
|
초록보기
Currently, physical activation methods such as steam or carbon dioxide (CO2) activation exhibits much lower efficiency on developing the porosity compared to chemical activation such as potasium hydroxide (KOH) activation. In this work, we report the hydrogen peroxide (H2O2)/steam activation as a simple and green approach to improving the efficiency of physical activation in developing porosity on carbonaceous materials. And we have investigated the effect of oxygen functionalities generated during activation on CO2 capture under flue gas of coal-fired power plants. This study also provides evidence for physisorptive CO2 capture via VSA or pressure swing adsorption (PSA) processes of carbon materials, including practical applications.
|
|
|
다운로드
(기관인증 필요)
|
|
초록보기
In this work, the sulfur (S) -doped porous carbons (PCs) were derived from polythiophene (PTh) as a S-riched carbon precursor and prepared by chemical activation with potassium hydroxide (KOH). The lithium adsorption experiments were carried out to analyze the influence of porous texture properties changed by the chemical activation of PCs on adsorption rate. From the experimental results, it was observed that the extent of adsorption process depends on the sulfur (S) and oxygen (O) group increases. Consequently, it could be noted that lithium ion recovery behaviors are greatly influenced by the surface functional groups and textural properties of PCs surfaces, resulting in enhanced electron acceptor-donor interaction at interfaces.
|
|
|
다운로드
(기관인증 필요)
|
|
초록보기
Recently, many researchers have focused on the development of porous materials for hydrogen (H2) storage media. In case of hydrogen (H2) physisorption, subnanometer micropores of less than 1 nm are known for their excellent performances, but their exact contribution and temperature-dependent adsorption performance are still ambiguous. Until now, many adsorption models including Langmuir, Freundlich, and Toth have been proposedbefore, however, they could not contain the porosity of the materials, so there is still a difficulty in revealing the correlation between porosity and adsorption performance. We have proposed a new model based on DFT pore volumes to investigate the ambiguous correlation between H2 adsorption and micropores. Our approach is a completely different approach from the conventional adsorption models and enables the analysis of the physisorption behavior of the gases by applying the porosity of the materials.
|
|
|
다운로드
(기관인증 필요)
|
|
초록보기
현대 사회는 지속적인 화석 연료의 사용에 의해 대기중 이산화탄소 농도가 증가하게 되었습니다. 이렇게 증가된 이산화탄소는 지구온난화 및 여러가지 환경문제들의 주범으로 지목되고 있으며, 전 세계적으로 이산화탄소의 저장 또는 활용에 대한 해결법을 연구하고 있습니다. 여러 연구들 중에서도 빛 에너지를 이용한 이산화탄소의 광환원을 통한 메탄화가 주목받고 있습니다. 이는 친환경적일 뿐만이 아니라 무한한 에너지를 가진 태양광을 이용할 수 있다는 점에서 연구 가치가 있습니다. 본 연구에서는 이산화탄소 광환원의 대표적 광촉매인 ZnO를 바탕으로 SPR효과를 사용할 수 있는 Cu와 풍부한 전자를 가진 Graphene을 이용하여 CO2 광환원률을 증가 시키고자 하였습니다. 촉매는 수열합성법으로 합성되었습니다. XRD, HR-TEM를 이용하여 촉매의 격자 구조와 모양을 확인하였고, XPS를 이용하여 각 원소들의 산화 상태를 분석하였습니다.
|
|
|
다운로드
(기관인증 필요)
|
|
초록보기
In this study, thermal conductive film was prepared using epoxy as matrix and graphite as filler. To enhance the dispersion of graphite in the epoxy matrix, fluorination treatment was conducted at room temperature using F2 and N2 gas. The chemical compositions of surface of the fluorinated graphite were investigated by X-ray photoelectron spectroscopy (XPS) and the dispersion of graphite in matrix were investigated by UV-Vis transmittance. The thermal conductivity of the prepared films was measured using laser flash method. XPS shows after fluorination treatment, fluorine functional group was introduced about 12 at% on the surface of graphite. In addition, UV-Vis transmittance of fluorinated graphite increased up to 77% than pristine graphite, and its thermal conductivity also increased about 65% compared to pristine graphite/epoxy film. It is attribute to electrostatic repulsion effect by fluorine functional group introduced on the graphite surface that enhanced dispersion stability.
|
|
|
다운로드
(기관인증 필요)
|
|
초록보기
In this study, Graphene nanoplatelet (GnP) was used as flame retardant. GnP/Phenolic foam (PF)/Wood composite board was fabricated with different GnP contents as 5, 10, 20 wt%. The thermal properties of composite boards were investigated by thermogravimetric analysis and flame retardancy by limiting oxygen index (LOI) test. The initial decomposition temperature of composite board was delayed with increase of GnP content. Also, the char yield increased up to 9.7% when GnP was added with 20 wt%, whereas char yield of raw wood board and PF added board is 0 and 1.9%, respectively. In addition, LOI value of raw wood board was 23.8%, while that of GnP 20 wt% added composite board was 31.7%. It was confirmed that addition of GnP improves the flame retardancy of wood-based composite board. These results are attributed by higher char yield, which prevents the contact with oxygen and delays the combustion of composite board.
|
|
|
다운로드
(기관인증 필요)
|
|
초록보기
항공유를 구성하는 다양한 탄화수소류 화합물들은 대부분 파라핀 성분으로 구성되어 있는 것으로 알려져 있다. 또한 일정한 범위 및 분포를 지니는 탄소수를 가지는 탄화수소류 화합물들로 이루어져야 연료로서 지니는 다양한 물성들의 제어가 가능하고 사용될 수 있는 항공유로서의 용도 또한 달라진다. 항공유를 구성하는 파라핀 성분의 탄화수소류 화합물들은 대체적으로 이소-, 노말- 및 사이클로-파라핀들인 것으로 알려져 있으며, 이러한 파라핀 탄화수소류 화합물들의 탄소수 범위 및 분포, 그리고 조성에 따라 항공유로서 지니는 밀도, 어는점, 인화점 등의 연료물성이 달라진다. 본 연구에서는 항공유를 구성하는 다양한 노말-, 이소-, 사이클로-파라핀으로 구성된 탄화수소류 화합물의 탄소수 범위 및 분포, 조성 등이 항공유급 연료물성인 밀도, 어는점, 인화점 등에 미치는 영향을 살펴보았다.
|
|
|
다운로드
(기관인증 필요)
|
|
초록보기
Pharmaceuticals and PFASs (perfluoroalkyl substances) presented in water environment have gained immersing attention due to their potential harmfulness to human and ecosystem. In this study, the removal efficiencies of several representative pharmaceuticals and PFASs by various advanced drinking water treatment processes (ozonation, GAC adsorption, and RO process) were investigated. It was found that chemically-robust PFASs were hardly removed by ozonation, whereas GAC and RO processes showed relatively higher removal efficiency. Among the pharmaceuticals, carbamazepine, crotamiton and sulfamethoxazole were effectively removed by all the above processes, however, metformin showed relatively low removal efficiency due to its chemical stability and high hydrophilicity.
|
개인회원가입으로 더욱 편리하게 이용하세요.
아이디/비밀번호를 잊으셨나요?