검색결과

검색조건
좁혀보기
검색필터
결과 내 재검색

간행물

    분야

      발행연도

      -

        검색결과 51

        2.
        2024.02 KCI 등재 구독 인증기관 무료, 개인회원 유료
        Aqueous Zn-ion batteries (ZIBs) are very attractive owing to their high safety and low cost. Among various cathode materials, organic materials-based electrodes incorporating various redox functional groups have gained significant attention in the field of ZIBs due to their benefits of a tunable structural design, facility, eco-friendly, and possibility of multivalent energy storage. Herein, we demonstrate the nanostructured organic active materials deposited onto the CNT networks (HyPT@ CNT) for flexible ZIBs. This HyPT nanorods were obtained reassemblying the herringbone structured 3,4,9,10-tetracarboxylic dianhydride through a hydrothermal process in the presence of acid. These HyPT@CNT hybrids were electronically conductive and redox active, as well as could be fabricated into a flexible electrode achieving flexibility from mechanical integrity of robust networked structure. The as-fabricated flexible ZIBs delivered the high capacity of 100 Ah g− 1 at a current density of 0.1 A g− 1 and long-term cycling performance exceeding 5000 cycles. Consequently, these electrochemical performances are associated with the redox reactivity of carbonyl groups as verified by spectroscopic and electrochemical characterizations and the hybridization of HyPT nanorods with CNT networks.
        4,800원
        3.
        2023.10 구독 인증기관·개인회원 무료
        We investigated the behavioral attractive responses of a lepidopteran larva parasite, Exorista japonica to 10 synthetic herbivore-induced plant volatiles (HIPVs). These synthetic HIPVs have been revealed the attractive effect on several parasites. For each of the HIPVs, we asked the following two questions : (1) Which volatiles show the attractiveness to this parasitoid, (2) Whether the attractant directly or indirectly affects the host settlement and parasitism of the parasitoid. To experimentally address these questions, we performed 2 and 4 choice indoor cage tests. E. japonica adults were significantly attracted to benzaldehyde and (Z)-3-hexen-1-ol showing higher settlement and parasitic rates on Spodoptera litura of treatments. Compared to the untreated plots, the average parasitism of E. japonica on S. litura larvae in the benzaldehyde treatments increased by approximately 20%.
        6.
        2022.08 KCI 등재 구독 인증기관 무료, 개인회원 유료
        One of the promising supercapacitors for next-generation energy storage is zinc-ion hybrid supercapacitors. For the anode materials of the hybrid supercapacitors, three-dimensional (3D) graphene frameworks are promising electrode materials for electrochemical capacitors due to their intrinsic interconnectivity, excellent electrical conductivity, and high specific surface area. However, the traditional route by which 3D graphene frameworks are synthesized is energy- and time-intensive and difficult to apply on a large scale due to environmental risks. Here, we describe a simple, economical, and scalable method of fabricating grafoil (GF) directly into a graphite–graphene architecture. Both synthesizing of a porous structure and functionalization with interconnected graphene sheets can be simultaneously achieved using electrochemically modified graphite. The resultant graphite electrode provides a high capacitance of 140 mF/cm2 at 1 mA/cm2, 3.5 times higher than that of pristine grafoil, keeping 60.1% of its capacitance when the current density increases from 1 to 10 mA/cm2. Thus, the method to produce 3D graphene-based electrodes introduced in the current study is promising for the applications of energy storage devices.
        4,000원
        8.
        2021.08 KCI 등재 구독 인증기관 무료, 개인회원 유료
        Graphene fiber is considered as a potential material for wearable applications owing to its lightness, flexibility, and high electrical conductivity. After the graphene oxide (GO) solution in the liquid crystal state is assembled into GO fiber through wet spinning, the reduced graphene oxide (rGO) fiber is obtained through a reduction process. In order to further improve the electrical conductivity, herein, we report N, P, and S doped rGO fibers through a facile vacuum diffusion process. The precursors of heteroatoms such as melamine, red phosphorus, and sulfur powders were used through a vacuum diffusion process. The resulting N, P, and S doped rGO fibers with atomic% of 6.52, 4.43 and 2.06% achieved the higher electrical conductivities compared to that of rGO fiber while preserving the fibrious morphology. In particular, N doped rGO fiber achieved the highest conductivity of 1.11 × 104 S m−1, which is 2.44 times greater than that of pristine rGO fiber. The heteroatom doping of rGO fiber through a vacuum diffusion process is facile to improve the electrical conductivity while maintaining the original structure.
        4,000원
        10.
        2020.09 KCI 등재 구독 인증기관 무료, 개인회원 유료
        Influenza A virus (IAV) causes respiratory disease in birds and mammals, including pigs and humans. Infection by IAV in pigs increases not only economic losses in the swine industry but also the emergence of novel IAV variants via gene reassortment, which is important due to the susceptibility of both birds and humans to IAV. This study provides serological data obtained during a study to detect IAV infections in pigs in the Republic of Korea during 2018 and 2019. A total of 1,559 samples were collected from 74 domestic pig farms. Hemagglutination inhibition (HI) assays were performed using the A/Swine/Korea/25-13(H1N1), A/Swine/Korea/E102 (H1N2), and A/Swine/Korea/Cy10/2007 (H3N2) viruses as antigens. The HI assay results showed that 266 of the 1,559 samples were seropositive (17.0%). Among these, H1N1, H1N2, and H3N2 comprised 7.3% (114), 6.0% (93), and 8.8% (137) of the 1,559 samples, respectively. Co-infections of H1N1/H1N2, H1N1/H3N2, H1N2/H3N2 and H1N1/H1N2/H3N2 were observed in 2.1% (31), 1.5% (23), 1.5% (24), and 0.8% (13) of the 1,559 samples, respectively. Interestingly, IAV infections were detected in all nine provinces of the country.
        3,000원
        11.
        2019.06 KCI 등재 구독 인증기관 무료, 개인회원 유료
        In this paper, nitrogen (N)-doped ultra-porous carbon derived from lignin is synthesized through hydrothermal carbonization, KOH activation, and post-doping process for CO2 adsorption. The specific surface areas of obtained N-doped porous carbons range from 247 to 3064 m2/g due to a successful KOH activation. N-containing groups of 0.62–1.17 wt% including pyridinic N, pyridone N, pyridine-N-oxide are found on the surface of porous carbon. N-doped porous carbon achieves the maximum CO2 adsorption capacity of 13.6 mmol/g at 25 °C up to 10 atm and high stability over 10 adsorption/desorption cycles. As confirmed by enthalpy calculation with the Clausius–Clapeyron equation, an adsorption heat of N-doped porous carbon is higher than non-doped porous carbon, indicating a role of N functionalities for enhanced CO2 adsorption capability. The overall results suggest that this carbon has high CO2 capture capacity and can be easily regenerated and reused without any clear loss of CO2 adsorption capacity.
        4,000원
        12.
        2019.06 KCI 등재 구독 인증기관 무료, 개인회원 유료
        We studied the infection rate of and various metacercariocidal approaches to controlling Gymnophalloides seoi for prevention of human infection in cultured and natural oysters in Korea. The selected survey areas were Aphae-do (Shinan-gun, Jeollanam-do), which is an endemic area for G. seoi, and Tongyeong (Geonsangnam-do), which is the main production area of oysters in Korea. In the Tongyeong area, the metacercariae of G. seoi were not detected in cultured oysters (0/201) or wild oysters (0/134). Seventy-two G. seoi metacercariae were observed in 33 of 265 natural oysters collected from Aphae-do; however, metacercariae were not detected in the cultured oysters (0/1101) purchased from the Daejeon Fish Market. To investigate the viability of G. seoi metacercariae, various metacercariocidal treatments were used with 3.5% saline and oyster juice used as positive controls. The metacercariae survived for 75.4 h in 3.5% saline and 112.6 h in oyster juice. After the metacercariocidal treatment, G. seoi metacercariae were survived for 13.29 min in tap water, < 20 sec in 4.3% vinegar, no effect in a rinse of the whole oyster body in 70°C water for 1 sec, but 1 sec in a rinse of the whole oyster body in 90°C water for 1 sec. The greatest metacercariocidal effect on G. seoi was from rinsing oysters in 90°C water followed by those from treatment with 20% ethyl alcohol, 4.3% vinegar, and tap water. However, we suggest that the most actual prevention to G. seoi human infection is rinsing the oysters with tap water for at least 30 min.
        3,000원
        13.
        2019.04 KCI 등재 구독 인증기관 무료, 개인회원 유료
        Chlorella-derived activated carbon (CDAC) with a high specific surface area and hierarchical pore structure was prepared as a CO2 adsorbent and as a supercapacitor electrode material. During KOH activation of Chlorella-derived carbon, metallic K gas penetrated from the outer walls to the inner cells, and pores formed on the outer frame and the inner surface. Micropores were dominant in CDAC, contributing toward a high specific surface area (> 3500 m2/g) and a hierarchical pore structure owing to the cell walls. Consequently, CDAC exhibited a high CO2 adsorption capacity (13.41 mmol/g at 10 atm and room temperature) and afforded high specific capacitance (142 F/g) and rate capability (retention ratio: 91.5%) in supercapacitors. Compared with woody- and herbaceous-biomass-derived activated carbons, CDAC has a superior specific surface area when the precursors are used without any pretreatment under the same conditions due to their soft components such as lipids and proteins. Furthermore, developing microalgae into high-value-added products is beneficial from both economic and environmental perspectives.
        4,000원
        15.
        2018.10 구독 인증기관·개인회원 무료
        Gonggeom-ji is designated wetland protected area by the Ministry of Environment of Korea in 2011 because of it’s high biodiversity and historic value. It contains a reservoir, paddy and forest site which has diverse niches for insects. Three transect lines of 50m were designated. Data were collected in May, October, November in 2017 represented as seasons for spring, summer and autumn respectively. Quantitative methods were conducted along each transect line by sweeping and pitfall trap. Based on this study total of 1079 individuals of insect fauna were collected, representing 170 species in 60 families and 8 orders. The highest diversity, richness and evenness index were observed in the forest site in May(4.77, 8.6 and 0.91 respectively) and the highest dominance index was observed in the forest site in November(0.64). The highest similarity index was observed in the reservoir site in May and August(0.519).
        16.
        2018.10 구독 인증기관·개인회원 무료
        The mandible character of the Lucanidae is vary by considering of developmental difference in male individual specimen. Especially, species of Genus Cyclommatus Parry, 1862 presents strong mandibular allometry. In this research, The species group which related to Cyclommatus montanellus Möllenkamp, 1904 has been evaluated for the first time in this research with inner teeth composition and positioning to establish clear taxonomic key to each species.
        17.
        2018.05 구독 인증기관·개인회원 무료
        Piezoelectric harvester for road power generation was installed on test roads owned by Korea Highway Corporation. 24 harvesters were installed on the concrete pavement and the remaining 12 harvesters were installed on the asphalt pavement. After installation, power generation performance and environmental tests were carried out with three types of vehicles: compact / passenger cars / trucks. The running speed of the vehicle was 30 km/h, 60km/h, 90 km/h. The test results show that the larger the weight of the vehicle, the higher the power generation, the concrete road than the asphalt road, and the exposed type rather than the buried type. The generation amount according to the depth of buried was at least 2.2 times at the depth of 1cm than 5cm depth. When the delegator lighting test was performed using 12 harvesters, it was possible to light up more than 20 seconds in one vehicle due to the improvement of the charging circuit. In addition, the wireless communication module driving test enabled temperature sensing and data transmission for 25 seconds. In addition, there was no breakage of the pavement when driving more than 180 times, and the generation amount was maintained more than 90%. However, Test for the durability of the pavement and the self-durability of the harvester is required more than 180 times of vehicle driving conditions and required more than minimum of 6-12 months of long-term monitoring.
        18.
        2018.01 KCI 등재 구독 인증기관 무료, 개인회원 유료
        Hierarchically porous, chemically activated carbon materials are readily derived from biomass using hydrothermal carbonization (HTC) and chemical activation processes. In this study, empty fruit bunches (EFB) were chosen as the carbon source due to their sustainability, high lignin-content, abundance, and low cost. The lignin content in the EFB was condensed and carbonized into a bulk non-porous solid via the HTC process, and then transformed into a hierarchical porous structure consisting of macro- and micropores by chemical activation. As confirmed by various characterization results, the optimum activation temperature for supercapacitor applications was determined to be 700°C. The enhanced capacitive performance is attributed to the textural property of the extremely high specific surface area of 2861.4 m2 g–1. The prepared material exhibited hierarchical porosity and surface features with oxygen functionalities, such as carboxyl and hydroxyl groups, suitable for pseudocapacitance. Finally, the as-optimized nanoporous carbons exhibited remarkable capacitive performance, with a specific capacitance of 402.3 F g–1 at 0.5 A g–1, a good rate capability of 79.8% at current densities from 0.5 A g–1 to 10 A g–1, and excellent life cycle behavior of 10,000 cycles with 96.5% capacitance retention at 20 A g–1.
        4,000원
        19.
        2017.12 KCI 등재 구독 인증기관 무료, 개인회원 유료
        배초향은 항동맥경화나 항박테리아의 특성을 가지는 한약재에 널리 사용되는 영년생 약용식물이다. 연구의 목적은 수경재배에서 배양액의 종류와 PPFD값에 따른 배초향의 생장 및 항산화 물질의 변화를 조사하는 것이다. 배초향은 주야간 16:8 시간의 일장조건에서 150과 200 μmol·m-2·s-1 PPFD 조건과 일본원시(HES), 서울시립대(UOS), 유럽채소연구소(EVR), 오오츠카 배양액(OTS)을 이용하여 6주간 재배하였다. OTS 배양액조 건에서 자란 배초향의 지상부 및 지하부 건물중은 다른 배양액 처리구와 비교하여 유의적으로 높았다. 배초향의 틸리아닌 함량은 OTS 처리에서 가장 높았으며 다음으로 EVR, HES, UOS 순서로 낮아졌다. 총 아카세틴의 함량은 EVR처리에서 가장 높았으나 OTS처리와는 유의적 차이를 보이지 않았다. 또한 200 μmol·m-2·s-1 PPFD 조건에서 자란 배초향은 PPFD 150처리구와 비교하여 유의적으로 생체중과 건물중이 증가하였으며 기능성 물질은 틸리아닌과 아카세틴의 함량도 높았다. 본 연구는 수경재배 방식을 이용하여 식물공장에서 배초향을 재배할 경우 200 μmol·m-2·s-1 PPFD 조건과 OTS 배양액 조건에서 경제적인 광원조건으로 최적 바이오매스 생산량과 틸라아닌과 아카세틴의 함량을 증가시킬 수 있을 것으로 제안한다.
        4,000원
        20.
        2016.06 KCI 등재 구독 인증기관 무료, 개인회원 유료
        High pollutant-loading capacities (up to 319 times its own weight) are achieved by three-dimensional (3D) macroporous, slightly reduced graphene oxide (srGO) sorbents, which are prepared through ice-templating and consecutive thermal reduction. The reduction of the srGO is readily controlled by heating time under a mild condition (at 1 10–2 Torr and 200°C). The saturated sorption capacity of the hydrophilic srGO sorbent (thermally reduced for 1 h) could not be improved further even though the samples were reduced for 10 h to achieve the hydrophobic surface. The large meso- and macroporosity of the srGO sorbent, which is achieved by removing the residual water and the hydroxyl groups, is crucial for achieving the enhanced capacity. In particular, a systematic study on absorption parameters indicates that the open porosity of the 3D srGO sorbents significantly contributes to the physical loading of oils and organic solvents on the hydrophilic surface. Therefore, this study provides insight into the absorption behavior of highly macroporous graphene-based macrostructures and hence paves the way to development of promising next-generation sorbents for removal of oils and organic solvent pollutants.
        4,000원
        1 2 3