검색결과

검색조건
좁혀보기
검색필터
결과 내 재검색

간행물

    분야

      발행연도

      -

        검색결과 59

        1.
        2024.04 KCI 등재 구독 인증기관 무료, 개인회원 유료
        Graphene-modified melamine sponges (RGO-MSs) were prepared, as adsorbents with photothermal conversion ability, utilizing solar energy to achieve heavy oil temperature rise, viscosity reduction, and efficient adsorption recovery of highly viscous oil. The RGO-MSs were prepared through a simple impregnation method. The photothermal performance and heavy oil adsorption performances of RGO-MSs with different densities and thicknesses were observed. It was found that as the density increases, the thermal conductivity of RGO-MS increases too, leading to the increase of the average oil absorption rate. The reduction of thickness is beneficial to improving of the adsorption rate. The prepared RGO-MS with a density of 21.5 mg/cm−3 and a height of 1 cm (RGO-MS-3-1) shows excellent mechanical properties and fatigue resistance. Cyclic adsorption–desorption of RGO-MS-3-1 was achieved through extrusion/ ethanol washing. After 10 cycles of reuse through extrusion, the adsorption capacity decreased from 52.90 to 50.02 g g− 1, with a loss of 5.4%. The material was then washed with petroleum ether and ethanol in turn. Its adsorption capacity can restored to 98.8% of the initial value, showing a promising application prospect on heavy oil leakage treatment. The easily prepared RGO-MS exhibits excellent light absorption and photothermal oil adsorption properties, providing a good solution for the problem of heavy oil leakage at sea.
        4,500원
        2.
        2024.03 KCI 등재 구독 인증기관 무료, 개인회원 유료
        스펀지 도시는 도시가 물을 효율적으로 사용한다는 개념을 강조한다. 도로의 스펀지화는 스펀지 도시 의 가장 직접적인 구현이며, 도시의 침수 및 물 부족 문제를 해결할 수 있다. 본 연구에서는 지닝시 성화 로를 대상으로 하여 성화로 이용에 대한 인식 및 개선수요를 분석하기 위하여 성화로 주민, 환경미화원, 지닝시 택시운전자 및 도로 계획가를 대상으로 현장 인터뷰 및 설문조사를 실시하였다. 조사내용을 바 탕으로 성화로 이용빈도에 대한 인식과 인구통계학적 특성의 유의성을 검증하기 위해 교차분석을 수 행하였다. 선행연구와 성화로 이용 인식분석을 통해 스펀지형 도로, 친환경 생태도로 및 안전형 도로의 3대 도로유형을 설정하였다. 도로유형의 각 항목의 중요도가 성화로침수에 미치는 영향관계를 결정하 기 위해 선형회귀분석을 수행하였으며, 성화로 개선의 방향을 결정하기 위해 AHP 계층분석법을 이용 하여 가중치를 계산하여 각 항목의 중요도 점수를 분석하였다. 분석결과 성화로는 LID 기술, 생태형 비 탈면 설계 및 식생배치가 도로 스펀지화 개선의 주요방향임을 알 수 있다.
        4,000원
        3.
        2024.03 KCI 등재 구독 인증기관 무료, 개인회원 유료
        Wearable sensors with highly flexible and sensitive characteristics have attracted research interests in the promising field of electronic skin, health monitoring, and soft robotics. However, the developing of high-performance piezoresistive sensor is full of challenges due to the expensive equipment and complex procedures. Herein, we fabricate a reduced graphene oxide/ polyurethane composite sponge (GPCS) pressure sensor combining with dual-templates. The polyurethane (PU) sponge provides an elastic structure as solid template. Meanwhile, air bubbles as gas template are used to uniformly disperse graphene oxide (GO) sheets. The burst of air bubbles in the process of thermal treatment makes GO coating on the surface of PU skeleton, avoiding the aggregation of reduced graphene oxide. Therefore, the GPCS exhibits excellent compressibility and uniform coating structure. As a result, it also possesses high sensitivity (Gauge Factor = 3.00 in the range of 0–10% strain), fast response time (35 ms), and excellent cyclic piezoresistive stability (5000 loading–unloading cycles) when applied in the pressure sensor field. Moreover, the flexible wearable stress–strain sensor assembled by the GPCS can be easily adhered on the surface of human skin and precisely detect human movements such as elbow bending and finger bending. Such low-cost procedure and excellent sensing performance enable GPCS sensor to demonstrate tremendous application potential in the field of advanced wearable devices.
        4,000원
        4.
        2022.11 KCI 등재 SCOPUS 구독 인증기관 무료, 개인회원 유료
        Piezoelectric composite films which are enabled by inorganic piezoelectric nanomaterials-embedded polymer, have attracted enormous attention as a sustainable power source for low powered electronics, because of their ease of fabrication and flexible nature. However, the absorption of applied stress by the soft polymeric matrices is a major issue that must be solved to expand the fields of piezoelectric composite applications. Herein, a flexible and porous piezoelectric composite (piezoelectric sponge) comprised of BaTiO3 nanoparticles and polydimethylsiloxane was developed using template method to enhance the energy conversion efficiency by minimizing the stress that vanishes into the polymer matrix. In the porous structure, effective stress transfer can occur between the piezoelectric active materials in compression mode due to direct contact between the ceramic particles embedded in the pore-polymer interface. The piezoelectric sponge with 30 wt% of BaTiO3 particles generated an open-circuit voltage of ~12 V and a short-circuit current of ~150 nA. A finite element method-based simulation was conducted to theoretically back up that the piezoelectric output performance was effectively improved by introducing the sponge structure. Furthermore, to demonstrate the feasibility of pressure detecting applications using the BaTiO3 particles-embedded piezoelectric sponge, the composite was arranged in a 3 × 3 array and integrated into a single pressure sensor. The fabricated sensor array successfully detected the shape of the applied pressure. This work can provide a cost-effective, biocompatible, and structural strategy for realizing piezoelectric composite-based energy harvesters and self-powered sensors with improved energy conversion efficiency
        4,000원
        5.
        2022.08 KCI 등재 구독 인증기관 무료, 개인회원 유료
        The purpose of this study was to investigate the possibility of using air potato (Dioscorea bulbifera) powder to make sponge cakes. The sponge cake batter was made by adding 0, 10, 20, 30, and 40% of air potato powder, and the resultant anti-oxidative properties and quality characteristics were analyzed. The study showed that the height, batter yield, and loss rate of sponge cakes decreased as increasing amounts of air potato powder were added, but the weight, viscosity, moisture content, and specific gravity increased. An evaluation of the color showed that the L and b values were highest in the control group but the a value was highest in the 40% group. There was no significant difference between samples in terms of cohesiveness, although the study showed a significant increase in the hardness, chewiness, and gumminess as the quantity of air potato powder in the sponge cakes increased. The total polyphenol content and DPPH radical scavenging activity increased noticeably as more air potato powder was added to the sponge cakes. The results thus showed that the study groups with the addition of air potato powder showed higher antioxidant activity than the control group.
        4,000원
        6.
        2022.08 KCI 등재 구독 인증기관 무료, 개인회원 유료
        In this study, the quality properties were compared by replacing allulose with a ratio of 0%-100% instead of sugar used in sponge cake. There was no significant difference in specific gravity, pH, and degree Brix of the dough according to the allulose content, but the brightness decreased and the redness, and yellowness increased as the allulose content increased. The volume of the sponge cake decreased as the content of allulose increased. Symmetry was uniform in the cakes replaced with allulose compared to 100% sugar. There was no significant difference in baking loss and moisture content. Hardness, gumminess and chewiness increased as the replacement rate of allulose increased, and adhesiveness was highest in 100% allulose. In the hedonic evaluation, 100% sugar and allulose 25% samples showed no difference, and the other samples were evaluated lower than the control. The maximum replacement ratio of allulose for sponge cake is considered to be 50%.
        4,000원
        7.
        2022.02 KCI 등재 구독 인증기관 무료, 개인회원 유료
        This study investigated the physicochemical and antioxidant properties of sponge cakes made using different amounts (2 and 4%) of barley sprout powder (BSP) and green tea powder (GTP), respectively. The results showed that the baking loss rate of GS2 (2% green tea) and GS4 (4% green tea) was 12.39% and 11.96%, respectively in the green tea addition group, which was higher than that of the barley sprout group, but significantly lower than that of the control group at 13.34% (p<0.05). The specific volumes of the sponge cake containing barley sprout and green tea 2% and 4% were between 2.84- 2.95 mL/g, which was significantly higher compared to the control group at 2.69 mL/g (p<0.05). The sugar content was significantly higher in the control group and the barley sprout addition group at 2.30oBrix (p<0.05). As for the volume index, the control group with the lowest value at 13.43 showed a significant difference compared to the addition groups. The volume index significantly decreased as the addition amount increased, measuring 14.07 in BS4 (4% BSP) compared to 14.87 of BS2 (2% BSP) in the barley sprout group (p<0.05). In cross-sectional photography, the color became darker than that of the control group as the quantum of additives increased. In terms of the DPPH and ABTS radical scavenging activity, the total phenol content, and total flavonoid content, the groups with the addition of barley sprout and green tea showed higher antioxidant activity than the control group (p<0.05).
        4,000원
        8.
        2020.09 KCI 등재 구독 인증기관 무료, 개인회원 유료
        스펀지 도시는 도시재생 측면에 있어, 우수를 도시 내 흡수, 침투, 정화할 수 있도록 하는 도시 물 순환 시스템의 개념이다. 이 개념은 2012년 중국 저탄소 도시 및 지역 경제 발전과학 기술포럼에서 처음으로 제기되었으며, 이로 인해 스펀지 도시에 관한 중요성이 부각되었다. 하지만, 스펀지 도시 내 중요한 역할을 하는 스펀지형 도시공원은 일반적인 개념 외 실제 적용되는 설계원칙에 대한 내용이 미비하다. 따라서 본 논문은 중국 스펀지 도시의 시범 도시인 싼야(三亚)시가 추진한 솽슈(双修)와 솽청(双城) 프로젝트인 싼야시 동안(东岸) 습지공원을 연구 대상으로 선정하여 선행연구를 통해 추출된 7가지의 스펀지형 도시공원 설계원칙을 대상으로 현장답사를 하였다. 또한, 대상지 이용 시민, 정부 건설 담당 부처의 공무원, 공원 관리인원 등 3개 그룹으로 나누어 인터뷰 조사·분석 방법론을 적용했다. 연구 결과는 다음과 같다. 동안습지공원은 연결성 측면에서 상당히 양호한 연계를 구축하고 있다고 분석되었다. 기능 측면에서는 젊은층과 어린이를 고려한 공간 설계가 없으므로 모든 연령층을 고려한 설계방식이 적용되어야 한다. 또한 인프라 시설 측면에서 공원은 더욱더 많은 휴식과 편의 시설이 필요하다고 분석된다. 스펀지성을 분석한 결과 잔도교(栈道桥)와 계단식 홍수 방지 댐을 조성하여, 양호한 홍수 방지 저류시설이 조성되어 있다. 마지막으로 경제적 측면에서 공원의 유지 보호에 적어도 80명에 달하는 유지 인력이 소요되어 이를 유지할 수 있는 경제적 측면이 고려되어야 함을 알 수 있다. 현재 중국의 스펀지 도시는 여전히 탐색 단계에 대량 실천성 탐구가 필요하다. 즉, 본 연구에서 도출한 연결성, 기능성, 생태성, 지역성, 안전성, 스펀지 도시성, 경제성 등 7개 유형의 스펀지형 도시공원 기본 설계 원칙을 적용한다면 기존 스펀지형 도시공원뿐만 아니라, 향후 새롭게 조성할 스펀지형 도시공원에 기초 자료를 제시할 수 있을 것으로 판단된다.
        4,200원
        9.
        2019.12 KCI 등재 구독 인증기관 무료, 개인회원 유료
        This study was performed to examine the physicochemical and antioxidative properties of the sponge cakes with different contents (0, 2, 4, 6, 8%, w/w) of lemon balm (Melissa officinalis) powder (LBP). An increase in LBP content in the cake led to a significant increase in the baking loss rate, specific volume, DPPH radical scavenging activity, ABTS radical scavenging activity, total phenol contents and total flavonoid contents of the cakes (p<0.05). As the LBP content increased, significant decreases were shown in the specific gravity of batter, sugar contents, pH, lightness, redness and yellowness of the cakes (p<0.05). Ash contents, uniformity index and other textural properties of hardness, springness, cohesiveness, and brittleness did not show any significant differences between the sample groups (p>0.05). These results suggest that LBP can be applied to sponge cakes to achieve positive textural properties such as uniform pore formation and increased volume with increased antioxidant properties.
        4,000원
        13.
        2017.12 KCI 등재 구독 인증기관 무료, 개인회원 유료
        본 연구에서는 사군자탕 구성 재료의 기능성을 연구하고자 사군자탕가루를 스폰지 케이크에 첨가하여 제조하였다. 케이크에 대한 한약재의 첨가량은 6%로 5개(S1(사군자탕가루), S2(인삼가루), S3(백복령가루), S4(백출가루), S5(감초가루))의 첨가군으로 구성하였다. 한약 재료의 첨가에 따라 완제품의 부피감소가 SC> S1>S3>S2>S4>S5 순으로 낮게 나타났다. 제품의 저장 중 미생물학적 품질 평가에서 생균수는 SC에서 가장 높게 나타났으며 SC는 저장 7일째에 9x107 CFU/g로 가장 높다가 저장 10일째에는 2.5x106 CFU/g 으로 감소하였다. 한약재가 들어간 다른 시료에서는 낮게 나타나 특히 S5의 경우 같은 7일째에 1.2x102 CFU/g 으로 적게 나타났다. 제품의 조직특성은 견고성, 점착성, 씹힘성이 SC에 비해 다 높은 값을 가졌다. 항산화성을 측정한 결과 과산화기질 생성억제효과의 크기는 스폰지 케이크에서 S5>S4>S3>S2>S1>SC의 순으로 나타나 한약 재료의 첨가군의 항산화효과가 나타났다. 관능검사에서는 전체적인 기호도는 SC에 비해 S3가 가장 유의적으로 높은 점수를 나타냈고, S3>SC,S2>S1>S5>S4순으로 전체적인 기호도를 나타내었다.
        4,000원
        14.
        2017.12 KCI 등재 구독 인증기관 무료, 개인회원 유료
        White sponge nevus (WSN) is a rare autosomal dominant disorder characterised by rough thickening, fissure formation, and a whitish colour change in the oral mucosa. This disorder predominantly affects the nonkeratinized stratified squamous epithelium of the mucosa. We experienced a familial case of WSN (i.e., a mother and her two daughters) and performed keratin gene analysis and immunohistochemical staining. The results of a mutation analysis revealed the presence of a heterozygous missense mutation 344T to G in KRT13, predicting an amino acid change leucine (L) to arginine (R), in the 1A domain of the KRT13 polypeptide. Immunohistochemically, the loss of keratin 4 expression was found.
        4,000원
        16.
        2017.06 KCI 등재 구독 인증기관 무료, 개인회원 유료
        An agricultural waste, pomegranate (Punica granatum L.) peel is known to be rich in total phenolics, which are flavonoids having strong antioxidant effects. In this study, pomegranate peel sponge cakes were prepared with varying ratios of freeze dried pomegranate peel powder (0, 1, 3, 5, 7% (w/w)) to examine their effect on quality characteristics, retrogradation and antioxidant activities. The specific gravity and moisture contents of 3, 5, and 7% pomegranate peel powder showed higher values than the control and 1% group. Addition of pomegranate peel powder increased the batter yield, while there was a significant decrease in baking loss. Increasing pomegranate peel powder content significantly decreased the lightness (L) (from 75.03 to 57.04) and pH values, whereas redness (a), yellowness (b) and ΔE were increased. Increasing concentration of the peel powder also increased the hardness and chewiness, while the springiness and cohesiveness decreased. Considering the Avrami equation, Avrami exponene (n) decreased from 1.8055 (control) to 0.9199 (7% pomegranate peel powder). Time constant (1/k) was lowest in control (at 17.64) and highest in the 7% group (39.84). Total polyphenol, flavonoid content, DPPH and ABTS radical scavenging activities significantly increased with increments in the content of pomegranate peel powder. A sensory evaluation by the 7-point scaling method showed that the sponge cake containing 7% pomegranate peel powder had the highest scores in color, flavor, sweetness, chewiness and overall acceptability. Hence, it is considered that sponge cake supplemented with 7% pomegranate peel powder is the most appropriate for quality characteristics, retrogradation and antioxidant activities.
        4,500원
        18.
        2016.12 KCI 등재 구독 인증기관 무료, 개인회원 유료
        This study investigated the quality characteristics, antioxidant activities, and retarding retrogradation of sponge cakes made with 0%, 1%, 3%, 5% and 7% pumpkin (Cucurbita moschata Duch.) leaf powder. Specific capacity significantly increased with the addition (0.33~0.38), but baking loss and dough yield were not significantly different (p<0.05). In color, there was a decrease in the L-value, a-value and b-value, but △E increased in proportion to the amount of pumpkin leaf powder. Moisture content increased in the 0~3% additions, from 27.90~31.68%, but decreased in 5% and 7% (22.37% and 28.15%, respectively). pH tended to decrease significantly according to the amount of pumpkin leaf powder (p<0.05). Hardness increased with the addition of pumpkin leaf powder, and pumpkin leaf groups presented higher springiness and cohesiveness than the control. Chewiness was not significantly differ (p<0.05). In retarding retrogradation, Avrami exponent (n) showed that addition of 5% (0.1329) had more retarding retrogradation effect than the control (0.4319), whereas time constant (1/k) showed both 3% (100.00) and 5% (70.42) addition had more effect than control (18.45). Total phenols and flavonoids content increased proportionate to the addition levels. ABTS radical scavenging activity tended to increase according to the level of pumpkin leaf powder. In sensory properties, 5% addition showed maximum color, and 3% addition had the highest scores in flavor, moistness, sweetness, chewiness and overall acceptability. These results suggested that pumpkin leaf was a good addition to improve the quality characteristics, health and sensory preferences. The most appropriate proportion to have the effect of retarding retrogradation in sponge cake is 3%.
        4,000원
        1 2 3