We use vdW-corrected density functional theory (DFT) calculations with additional electron distribution correction to study the water binding chemistry of an Au nanoparticle supported on CeO2(111) with a linear step-edge. The initial structural model of Au/CeO2 used for DFT calculations is constructed by stabilizing a Au9 nanoparticle at the linear step-edge on a CeO2(111) slab. The calculated binding energy of a water molecule clearly shows that the interfacial site between Au and CeO2 binds water more strongly than the binding sites at the surface of Au nanoparticle. Subsequent water dissociation calculation result shows that the interface-bound water can be relatively easily dissociated into–OH and –H, providing a hydroxyl group that can be utilized as an oxygen source for CO oxidation. Based on the low dissociation energy of the interface bound water molecule, we suggest that the water at the Au-CeO2 interface can facilitate further oxidation of Au-bound CO. Our results point out that Au-CeO2 interface-bound water is beneficial for low-temperature oxidation reactions such as the water-gas shift reaction or preferential CO oxidation reaction.

Identifying the water circulation status is one of the indispensable processes for watershed management in an urban area. Recently, various water circulation models have been developed to simulate the water circulation, but it takes a lot of time and cost to make a water circulation model that could adapt the characteristics of the watershed. This paper aims to develop a water circulation state estimation model that could easily calculate the status of water circulation in an urban watershed by using multiple linear regression analysis. The study watershed is a watershed in Seoul that applied the impermeable area ratio in 1962 and 2000. And, It was divided into 73 watersheds in order to consider changes in water circulation status according to the urban characteristic factors. The input data of the SHER(Similar Hydrologic Element Response) model, a water circulation model, were used as data for the urban characteristic factors of each watershed. A total of seven factors were considered as urban characteristic factors. Those factors included annual precipitation, watershed area, average land-surface slope, impervious surface ratio, coefficient of saturated permeability, hydraulic gradient of groundwater surface, and length of contact line with downstream block. With significance probabilities (or p-values) of 0.05 and below, all five models showed significant results in estimating the water circulation status such as the surface runoff rate and the evapotranspiration rate. The model that was applied all seven urban characteristics factors, can calculate the most similar results such as the existing water circulation model. The water circulation estimation model developed in this study is not only useful to simply estimate the water circulation status of ungauged watersheds but can also provide data for parameter calibration and validation.

기름/물 분리막은 다른 분리 기술들에 비해 낮은 에너지 비용과 높은 성능 수준을 갖고 있다. 초친수성과 수중에 서 소유성은 효과적인 기름/물 분리막을 개발하는 데 가장 중요한 요인으로 작용한다. 이와 더불어 방오속성과 생분해성도 효과 적인 기름/물 분리막을 개발할 때에 고려되는 중요한 요소들이다. 본 리뷰 논문에서는 다양한 화학성분과 형태를 변형시켜 개발된 기름/물 분리막의 특성과 분리 효율을 개선한 연구들을 소개한다.

The purpose of this study is to analyze outcome of the project to improve old water supply facilities in Airforce Base to improve water revenue rate. To achieve the objective of this study, First, literature review is conducted to clearly define the concept of water revenue rate improve project. Second, WASCO project on 2 Airforce base review and smart water management pilot project on 1 Airforce base is conducted. Third, economical analysis of project is conducted to examine the outcome. As a result, WASCO and smart water management pilot project on Airforce base was effective to improve water revenue rate. Finally, the improvements were suggested after investigating the key factors on water revenue rate improve project. In the future, this study will be used as a baseline for developing water revenue rate improve project.

이 논문은 섬과 관련된 시를 어떻게 읽을 것인가를 논의한다. 라지브 S. 파트키는 최근 좋은 저서 『섬과 시: 물질성과 창조적 상상력』이라는 저서를 출간했는 데, 이것은 영문학분야에서 앞으로 본 분야에 대한 논의를 활성화할 것으로 기대한다.

In this study, four types of water-heavy fuel oil hybrid emulsion oil were manufactured depending on the moisture content ratio in order to reduce exhaust emissions of heavy fuel oil(Bunder-C), which is necessarily used in vessels, power plants and boilers. The components of the manufactured emulsion oil were analyzed using the ISO standard testing method. The analysis result showed that in the EM25 fuel with a maximum moisture content ratio of 25.0%, the moisture content was 25.0%, the sulphur content was 0.20%, the kinematic viscosity was 144.8mm2/s, the specific gravity was 0.9382, and the flash point was 100 Celsius degrees or above.

본 연구는 여대생 900명을 대상으로 물 섭취량과 커피 섭취량에 따른 건강체력 및 비만에 대한 차이를 알아보고자 하였다. 측정은 건강체력요인 체력에 근력(악력, 배근력), 근지구력(윗몸일으키기),유연성(앉아앞으로굽히기) 심폐지구력(하버드스텝)을 측정하였고, 체성분 측정기기 Inbody를 이용하여 신체조성(세포내액, 세포외액, 단백질, 무기질, 체수분량, 근육량, 제지방량, 체지방량)과 비만(BMI, 체지방률, 복부지방률, 비만도)의 각 항목을 측정하였다. 자료처리는 SPSS를 이용하여 이원변량분석과 일원변량분석을 실시하였다. 그 결과 건강체력과 비만에 대한 물과 커피 섭취량 집단 간 상호작용은 나타나지 않았다. 각 독립변인 별 일원변량분석을 실시한 결과 건강체력요인 중 체력요인은 물과 커피 섭취량에 따른 유의미한 차이는 나타나지 않았다. 그러나 신체조성(세포내액, 단백질, 무기질, 체수분량, 근육량, 제지방량)에서 물 7잔 이상 섭취 집단이 1∼4잔 섭취 집단보다 유의미하게 높았으며, 커피는 3∼4잔 섭취 집단이 미섭취 집단에 비하여 유의미하게 높았다. 비만요인의 경우 물 섭취량에 따라 유의미한 차이는 나타나지 않았지만, 커피의 경우 비만도에서 3∼4잔 섭취 집단이 미섭취 집단에 비하여 비만도가 높게 나타나, 커피는 물과 달리 비만과 관련이 있음을 알았다. 차후 물과 커피와 같은 다양한 음료 섭취에 대한 성별, 연령대별 차이에 관한 연구가 진행되어 진다면 보다 나은 건강을 위한 개인별 특성에 따른 수분 섭취방법으로 활용될 수 있을 것이다.

Pumpkin sweet potato (Ipomoea batas L.) has been known as a traditional remedy and food source, not only in South Korea but worldwide. It is rich in fiber, potassium, vitamin C, and other minerals and vitamins, making it a nutritional food loved by many. showed that pumpkin sweet potato had antioxidant biological effects. The in vitro study showed that both splenocytes and cytokine production byactivated peritoneal macrophages increased when water extracts were supplemented at 100 and 250 μL/mL. Notably, the production of IL-1β, TNF-α, and IFN-γ by splenocytes was significantly increased at 100 μL/mL. The results suggest that supplementation with pumpkin sweet potato (Ipomoea batas L.) water extract may enhance immune function by stimulating splenocyte proliferation and improving cytokine production, activating macrophages in vitro.

ODA finance in the water sector has decreased after reaching a peak in 2012 although total ODA commitments have steadily increased according to OECD DAC data. However, climate finance in the water sector has increased so much since 2013 according to 7 MDB Joint report on Climate Finance. Water, especially, in climate change is the main issue for adaptation, and the total finance in the water sector reached 50% of the international public adaptation finance in 2016. However, the procedures for approval and the requirements of the proposals for climate funds are different from those for development finance. Notwithstanding the changes in money flows in the water sector, most korean engineering consulting firms in the water infrastructure area are not ready to win the funds relating to climate change. Therefore, It is important to understand a variety of sources of climate funds, characteristics, funding scale on each purpose and procedures for approval. Korean government needs to provide the firms the opportunities to buildup experiences by getting involved in climate adaptation projects with the financial support for developing PPFs, concept notes, and proposals.

Cerium oxide (ceria, CeO2) is one of the most wide-spread oxide supporting materials for the precious metal nanoparticle class of heterogeneous catalysts. Because ceria can store and release oxygen ions, it is an essential catalytic component for various oxidation reactions such as CO oxidation (2CO + O2 2CO2). Moreover, reduced ceria is known to be reactive for water activation, which is a critical step for activation of water-gas shift reaction (CO + H2O → H2 + CO2). Here, we apply van der Waals-corrected density functional theory (DFT) calculations combined with U correction to study the mechanism of water chemisorption on CeO2(111) surfaces. A stoichiometric CeO2(111) and a defected CeO2(111) surface showed different water adsorption chemistry, suggesting that defected CeO2 surfaces with oxygen vacancies are responsible for water binding and activation. An appropriate level of water-ceria chemisorption energy is deduced by vdW-corrected non-local correlation coupled with the optB86b exchange functional, whereas the conventional PBE functional describes weaker water-ceria interactions, which are insufficient to stabilize (chemisorb) water on the ceria surfaces.

Synthesizing one-dimensional nanostructures of oxide semiconductors is a promising approach to fabricate highefficiency photoelectrodes for hydrogen production from photoelectrochemical (PEC) water splitting. In this work, vertically aligned zinc oxide (ZnO) nanorod arrays are successfully synthesized on fluorine-doped-tin-oxide (FTO) coated glass substrate via seed-mediated hydrothermal synthesis method with the use of a ZnO nanoparticle seed layer, which is formed by thermally oxidizing a sputtered Zn metal thin film. The structural, optical and PEC properties of the ZnO nanorod arrays synthesized at varying levels of Zn sputtering power are examined to reveal that the optimum ZnO nanorod array can be obtained at a sputtering power of 20W. The photocurrent density and the optimal photocurrent conversion efficiency obtained for the optimum ZnO nanorod array photoanode are 0.13 mA/cm2 and 0.49 %, respectively, at a potential of 0.85 V vs. RHE. These results provide a promising avenue to fabricating earth-abundant ZnO-based photoanodes for PEC water oxidation using facile hydrothermal synthesis.

In this paper, internal and external flow analysis of nozzle for a automatic bike washing machine was performed using Ansys Fluent, by varying nozzle injection pressure and angle. The pressure and velocity distributions generated at the nozzle outlet from internal flow analysis were applied for inlet condition of the external flow analysis of the nozzle. As a criterion for the cleaning efficiency, the shear stress condition provided by EHEDG[5] was used and an area of shear stress of 3 Pa or more according to the spray angle and pressure was compared. It is expected that the results of this paper will be applied to the development of automatic contactless bike washing nozzle.

Due to global climate change, Korea is experiencing flooding and drought severely. It is hard to manage water resources because intensive precipitation during short periods and drought are commonly occurred in Korea, recently. Severe drought occurred in 2015 and 2017 in the islands, and coastal and inland areas in Korea, and the citizens experienced decreased water supply and emergency water service by using bottled water. Therefore, the Korean government provided additional governmental funds such as the grant of drought disaster. In this study, we tried to calculate the cost of water for drought response based on the cost of tap water for the regional local governments in Korea and the grant of drought disaster by the Ministry of the Interior and Safety in Korea, etc. The estimated costs of water for drought responses in coastal and inland areas which have a chance to apply alternative water sources such as brackish or seawater desalination and water reuse in Korea were higher than in other areas in Korea. Additionally, as the novel approach of drought response, the 300 m3/day-scale desalination vessel was suggested to provide desalinated water for the islands in Korea. The estimated expenses of water supply for the target island areas (Sinan-gun and Jindo-gun) by the desalination vessel was lower than those by emergency water service by using bottled water.