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        검색결과 466

        1.
        2026.04 KCI 등재 구독 인증기관 무료, 개인회원 유료
        Lithium-ion batteries (LIBs) are widely used as key components in electric vehicles (EVs) and energy storage systems (ESS) owing to their high energy density, long cycle life, and stable operation. The rapid expansion of the EV market has intensified the demand for advanced graphite anode materials that combine cost competitiveness with superior electrochemical performance, including fast-charging capability and structural stability. This study presents an integrated approach for optimizing the physical spheronization of natural graphite and synthesizing a high-performance coating pitch (CP) for chemical spheronization. The correlation between mechanical stress and morphological evolution during the process was quantitatively analyzed using an Air Classifier Mill (ACM). Optimal spheronization was achieved by aligning theoretically calculated stress levels (≈ 3.72 MPa for particle rounding and > 14.86 MPa for fracture) with experimental results. High-performance coating pitches were prepared via stepwise polymerization of pyrolysis fuel oil (PFO), followed by Thin Layer Evaporation (TLE)-based molecular weight distribution tailoring. The resulting pitch exhibited a softening point of 279.4 °C, coking value of 70.7%, and zero quinoline insoluble (QI) content, and was applied as a coating precursor. The optimized spheronized graphite anode showed excellent electrochemical properties, including an initial Coulombic efficiency of 92.6% and 97.4% capacity retention after 50 cycles. Electrochemical impedance spectroscopy (EIS) and galvanostatic intermittent titration technique (GITT) analyses further confirmed efficient lithium-ion diffusion at both the surface and core, demonstrating suitability for fast-charging LIB applications.
        5,700원
        2.
        2026.03 구독 인증기관·개인회원 무료
        The integrity of interlayer bonding in asphalt pavements is a critical factor to ensure the structure behaves as a unified, monolithic system. Common issues like dust contamination on the receiving surface and inadequate tack coat application create weak interfacial planes that promote localized shear deformation specifically in high-traction zones like braking and turning areas. This study introduces a transferable framework that integrates lab-based interlayer bond characterization, composite fatigue testing, and finite element (FE) modeling to assess pavement performance under realistic field conditions.Two tack coats were used in this study, including regular tack coat (RSC-4) and clean tack coat (ILT-4) and considered 0%, 50% (remaining 50% was covered with dust), and 100% of the contact surface area, at three distinct tack coat application rates. Peak shear strength, initial stiffness, and fractured energy were determined from monotonic shear tests for quantifying bonding state and for FE simulations. Four-point bending (4PB) test was used to characterize fatigue performance, using normalized stiffness s(N), fatigue life and mid-life degradation rate or damage rate (DR). To relate the findings with field behavior, FE simulations estimate shear demand during braking, allowing a demand-to-capacity comparison. Results indicate that dust samples have 10%-30% lower bonding strength and must reach shear fail at the service life at the breaking zone with -0.93 midlife damage rate. Considering DR as a primary performance indicator, the framework provides the ultimate recommendations such as ensure surface cleanliness, uniform tack coat application, and quality control in high-stress zones.
        3.
        2025.12 KCI 등재 구독 인증기관 무료, 개인회원 유료
        The co-sintered phosphor of cerium-doped yttrium aluminum garnet (YAG:Ce) and aluminum nitride (AlN) is a promising material for next-generation light-emitting diode lighting applications. Despite AlN’s excellent thermal conductivity, its high sintering temperature and surface reactivity limit its industrial use in co-sintered phosphors, and effective methods to improve its sinterability without compromising properties remain underexplored. In this study, the sinterability of the AlN and YAG:Ce composite is improved by coating AlN particles with a soluble carbon material (SCM) prior to sintering. SCM coating leads to a 6.75% increase in photoluminescence (PL) intensity under 15 W laser excitation and a 6.85% improvement in thermal conductivity, which suppresses thermal quenching. The enhanced thermal conductivity also minimizes PL decay over time, thereby maintaining high luminosity for extended periods. Furthermore, the hardness and handling properties of the obtained sintered body are significantly improved, with hardness increasing by 112.3% when SCM-coated AlN is used. Notably, the SCM does not remain in the final product, as it is fully removed during sintering, leaving no impurities or adverse effect on the material’s properties. Given its ability to easily and uniformly coat ceramic particles, SCM coating holds promise for broader application in enhancing the sinterability and performance of various ceramic-based materials.
        4,000원
        4.
        2025.12 KCI 등재 구독 인증기관 무료, 개인회원 유료
        Medial patellar luxation is a common orthopedic disorder in dogs, and advanced cases with severe skeletal deformities or femoropatellar osteoarthritis are often unresponsive to conventional techniques. Patellar groove replacement (PGR) has been proposed as an alternative surgical option; however, systematic comparisons of coating technologies for veterinary PGR implants remain limited. This study aimed to evaluate the physicochemical properties, biological compatibility, and functional performance of a newly developed titanium nitride (TiN)–coated PGR system compared with a clinically available amorphous diamond-like carbon (ADLC)–coated device. TiN-coated prototypes were fabricated using Ti-6Al-4V alloy by injection molding combined with arc ion plating, which requires simpler equipment and lower production costs than the vacuum plasma deposition used for ADLC. Physicochemical evaluations, including corrosion resistance, hardness, surface roughness, and coating thickness, were conducted following International Organization for Standardization (ISO) and Korean Industrial Standards (KS) guidelines. In vitro biocompatibility was assessed using MTT and cell adhesion assays with L-929 fibroblasts, while inflammatory cytokine profiling (interleukin [IL]-1β and IL-6) in a rat subcutaneous model was used to evaluate local tissue responses. Functional feasibility was examined in a canine femoral model bilaterally implanted with TiNor ADLC-coated PGR systems and monitored for one year through clinical, radiographic, computed tomography (CT), magnetic resonance imaging , and micro-CT assessments. Both coatings demonstrated excellent corrosion resistance and absence of cytotoxicity. TiN-coated implants showed slightly greater hardness and coating thickness, with comparable surface roughness and biocompatibility. All implants maintained stable fixation, proper patellar tracking, and satisfactory bone–implant integration. These findings indicate that TiN-coated PGR implants achieve biological and mechanical performance equivalent to ADLC devices while offering advantages in manufacturing simplicity, scalability, and cost-efficiency, supporting their clinical applicability in veterinary orthopedics.
        4,900원
        5.
        2025.12 KCI 등재 구독 인증기관 무료, 개인회원 유료
        Silicon based anode materials offer high theoretical capacity but suffer from severe volume expansion and unstable interfacial properties during repeated lithiation and delithiation, resulting in rapid performance degradation. In this study, a thin aluminum oxide coating layer was deposited on Si/SiOx Carbon anode materials using a powder atomic layer deposition (PALD) process to address these limitations. EDS mapping and XRD analyses confirmed the uniform formation of an amorphous aluminum oxide coating with increasing thickness as the deposition cycles increased. Electrochemical evaluation showed that the electrode coated with 5 PALD cycles exhibited approximately 78% higher capacity retention after 100 cycles at 1 A g-1 and a higher initial Coulombic efficiency compared to the bare electrode. The coated electrode also delivered approximately 22% higher capacity at a high current density of 5 A g-1, indicating enhanced rate capability. Cyclic voltammetry analysis revealed increased surface controlled reaction contributions and improved reaction kinetics. These results demonstrate that PALD derived aluminum oxide coatings effectively stabilize the electrode electrolyte interface and enhance the electrochemical performance of silicon based anodes, highlighting their potential for next generation high capacity lithium ion batteries. generation high capacity lithium ion battery anode materials.
        4,000원
        7.
        2025.12 KCI 등재 구독 인증기관 무료, 개인회원 유료
        The engineered materials arresting system (EMAS) is a safety facility installed at the end of runways to safely stop aircraft when runway overruns occur. The EMAS comprises porous panels composed of specialized materials; however, direct exposure to environmental factors, such as moisture infiltration, freeze–thaw cycles, and ultraviolet radiation, may cause performance degradation. In regions with four distinct seasons and significant temperature variations, such as South Korea, changes in the physical properties and durability of porous panels can pose significant challenges. Therefore, a protective top coating must be applied to EMAS panels to protect the panels from environmental stress and ensure long-term durability. This study presents a preliminary investigation into the development of a high-performance polyureabased top coating to effectively protect the components of an EMAS and crushable concrete panels as well as to maintain the system’s long-term durability and arresting performance. First, optimal formulations were determined via a design study, where the index ratio (the equivalent ratio of polyurea resin to the curing agent) and the NCO content of the isocyanate component were varied. Second, the curing behavior, mechanical properties, and temperature dependence were evaluated. Polyurea—a high-performance elastomer formed by the reaction between isocyanate and amine-based curing agents—exhibits rapid reactivity, complete waterproofing, excellent flexibility, and elasticity, thus satisfying the essential requirements of EMAS top coatings. Considering the balance between stiffness and flexibility, an index ratio of 1.05 and an NCO content of 16.0% were identified as the optimal mix design. Mechanical testing demonstrated a high tensile strength of 20.0 MPa, an outstanding elongation at break of 388%, and a tear strength of 100 N/mm, thus indicating sufficient durability and flexibility to withstand aircraft jet blast and temperature fluctuations. Temperature-dependence tests confirmed that the elongation remained at 136% (at -20 °C) and the tensile-strength ratio at 68% (at 60 °C), thus demonstrating that the coating can maintain stable performance in environments with significant seasonal temperature variations.
        4,000원
        8.
        2025.10 KCI 등재 구독 인증기관 무료, 개인회원 유료
        It is important to secure numerical accuracy while ensuring adhesion with high transparency and low yellowing properties to protect against physical impacts outside the drone. In addition, in order to derive high-quality results for preventing damage and discoloration from ultraviolet rays and atmospheric chemicals, a release layer process technology in which a silicone-based release is coated at a certain thickness and then cured at an appropriate temperature and time, and a technology for optimizing adhesion of adhesive thickness and solid content during adhesive coating were confirmed, and the protective film confirmed the results of surface suitability, retention, and stability evaluation over time for drone aircraft and external parts over a long period of time.
        4,000원
        10.
        2025.05 KCI 등재 SCOPUS 구독 인증기관 무료, 개인회원 유료
        Lithium- and manganese-rich layered oxide (LMRO) is considered a promising cathode material for lithium-ion batteries owing to its high capacity and energy density. However, operation at a high voltage of 4.8 V leads to several issues including low Coulombic efficiency, poor cycle life, slow kinetics, and voltage decay due to spinel phase transition, hindering commercialization. Herein, we synthesized a cobalt-free LMRO cathode and studied the effect of Nb2O5 and Sb2O3 coating layers on electrochemical performance. The Nb2O5 coating facilitated the formation of a LiNbO3 layer, which enhanced the initial electrochemical performance, including Coulombic efficiency and energy density. Meanwhile, Sb2O3 not only coated the surface but also doped into the bulk structure, thereby increasing capacity and improving rate capability. Comparative analysis using materials with different structural solubility revealed how oxide coatings influenced lithium-ion transport and electrochemical behavior. This study highlights the importance of interfacial engineering for optimizing LMRO cathodes for high-performance lithium-ion batteries.
        4,000원
        11.
        2025.05 KCI 등재 구독 인증기관 무료, 개인회원 유료
        Maintaining probiotic viability during storage, freeze-drying, and gastrointestinal transit is essential to ensure efficacy. The present study evaluated VitaShield Coating® (VSC), an innovative stabilization technology incorporating vitamins A, C, and E, for enhancing the viability of Bifidobacterium strains. VSC-coated B. bifidum BGN4 exhibited a significantly higher freeze-drying recovery rate (43.91±4.69%) compared to that of the uncoated group (15.31±6.53%, p<0.0001), with scanning electron microscopy (SEM) confirming preservation of structural integrity. Gastrointestinal stability also improved, as coated cells retained 26.21±2.41% viability in simulated gastric fluid, significantly outperforming uncoated cells (3.20±2.30%, p<0.0001). Gas chromatography-mass spectrometry (GC-MS) revealed a significant increase in polyunsaturated fatty acids (PUFAs) in coated cells, indicating enhanced membrane stability. Furthermore, storage stability of four Bifidobacterium strains (AD011, BORI, BGN4, and RAPO) was evaluated over 16 weeks at 25℃ and 30℃. The findings indicate that the VSC coating effectively protects probiotic strains under harsh storage conditions, mitigating viability loss over time. Overall, this study showed that the VSC coating serves as a multifunctional stabilization technology that provides mechanical, osmotic, and oxidative stress protection. Its ability to improve probiotic survival under harsh conditions enables its practical and scalable use in formulations and enhances stability.
        4,000원
        13.
        2025.02 KCI 등재 구독 인증기관 무료, 개인회원 유료
        For the commercialization of bipolar plates, several properties must be considered together. Electrical conductivity, corrosion resistance, contact resistance, mechanical strength, and light weight are essential evaluation factors, with corrosion resistance and durability being significant for unitized regenerative fuel cells (URFCs), which must operate in electrolysis and fuel cell mode. However, improving both properties is challenging, since corrosion resistance is largely inversely proportional to conductivity. In this study, to improve both properties together, composites composed of Pb and Zn with excellent conductivity and corrosion resistance were prepared with graphite powder and formed as a coating layer on the surface of 304 stainless steel (SS304) and evaluated for electrical conductivity and corrosion resistance. Among the ZnPb/C composites prepared at various ratios, Zn8Pb2/C exhibited the lowest transmittance resistance of 1.566 Ω, and improved electrical conductivity and durability compared to bare SS304.
        4,000원
        15.
        2024.10 KCI 등재 구독 인증기관 무료, 개인회원 유료
        높은 종횡비와 원자 수준의 얇은 두께를 갖는 다공성 2D 소재는 고성능 분리막 제작에 활용된다. 이를 위해서는 다공성 2D 소재를 다공성 지지체 위에 균일하게 도포할 수 있는 코팅법이 필수이다. 본 연구는 이를 위한 제올라이트 MFI 나노막의 간단하면서도 효과적인 코팅법을 제시한다. 직접합성법으로 합성된 제올라이트 MFI 나노막은 물에 분산되면서 동 시에 표면 활성을 보여, 이 특성을 활용하여 소수성 계면에 흡착시키는 것이 가능하다. 소수성 개질을 다양한 형태의 지지체 에 적용하여, 이들 표면에 고밀도의 나노막 흡착 코팅이 가능함을 보였다. 또한, 이 흡착코팅의 반복 수행을 통해 나노막의 완전피복을 달성하고, 이를 연속적인 MFI 필름 및 멤브레인으로 성장시킬 수 있었다. 이 간단한 코팅법은 제올라이트 나노막 뿐만 아니라, 표면활성을 보이는 다른 2D 소재에도 적용 가능할 것으로 보이며, 2D 소재의 활용도를 제고할 수 있을 것이다.
        4,200원
        16.
        2024.10 구독 인증기관·개인회원 무료
        본 논문에서는 다양한 기상 조건에서 시인성과 내구성을 향상시키도록 설계된 도로 표시용 UV 경화 코팅 시스템 개발을 위해 수행한 연구의 결과를 나타내었다. 제조된 UV 코팅을 사용해 차선 표시의 재귀반사도와 내마모성을 강화하고 포장가속시험(APT), 휠 트래킹 내구성 테스트 등 다양한 테스트를 통해 성능을 평가하였다. 이 결과를 바탕으로 도로 안전을 위한 야간 시인성 및 미끄럼을 개선하 고자 한다.
        18.
        2024.09 KCI 등재 SCOPUS 구독 인증기관 무료, 개인회원 유료
        Organic-inorganic hybrid coating films have been used to increase the transmittance and enhance the physical properties of plastic substrates. Sol-gel organic-inorganic thin films were fabricated on polymethylmethacrylate (PMMA) substrates using a dip coater. Metal alkoxide precursor tetraethylsilicate (TEOS) and alkoxy silanes including decyltrimethoxysilane (DTMS), 3-glycidoxypropyltrimethoxysilane (GPTMS), phenyltrimethoxysilane (PTMS), 3-(trimethoxysilyl)propyl methacrylate (TMSPM) and vinyltrimethoxysilane (VTMS) were used to synthesize sol-gel hybrid coating solutions. Sol-gel synthesis was confirmed by the results of FT-IR. Cross-linking of the Si-O-Si network during synthesis of the sol-gel reaction was confirmed. The effects of each alkoxy silane on the coating film properties were investigated. All of the organicinorganic hybrid coatings showed improved transmittance of over 90 %. The surface hardness of all coating films on the PMMA substrate was measured to be 4H or higher and the average thickness of the coating films was measured to be about 500 nm. Notably, the TEOS/DTMS coating film showed excellent hydrophobic properties, of about 97°.
        4,000원
        19.
        2024.09 KCI 등재 구독 인증기관 무료, 개인회원 유료
        With medical use of hemp, many medicinal cultivars were bred worldwide. Propagating cultivar using seed has a high cost. On the other hand, vegetatively propagating cultivar has various merits including short breeding period and uniformity. This study aimed to determine optimal conditions for propagating hemp after cutting, including sterilizing of rooting media, rooting hormone, and mixing ratio of growing media and sand of rooting media. Korean landrace strain of hemp plant was grown in Wagner pot (size: 1/2,000 a) for 60 days. Its branches were cut to 70∼80 mm in length and used for cutting slips. The rooting medium, a horticultural nursery medium, was autoclaved for 3 hours at 120 ℃. The mixing ratio of sand and nursery media was 9:1, 7:3, 5:5, or 3:7 in weight. Cutting slips were coated with rooting hormone (1-naphthylacetamide 0.4%) just before planting. Cutting materials were planted in a tray pot of 72 cells and grown in a walk-in-chamber for 28 days with a temperature of 25 ℃ and an intensity of radiation of 800 μmol/㎡/sec. Seedling rates were 61.1%, 77.8%, and 63.0% for mixing ratios of 1:9, 3:7, and 5:5 of sand mixed with horticultural nursery medium. These seedling rates were significantly higher than a seedling rate of 31.5 % for a mixing ratio of 7:3. Root lengths were 97 mm, 91 mm, and 81 mm for mixing ratios of 1:9, 3:7, and 5:5 of sand mixed with horticultural nursery medium. These root lengths were significantly longer than a root length of 37 mm for a mixing ratio of 7:3. Rooting rates were 81.1 % and 91.2 % for slips coated with rooting hormone and sterilized rooting media, respectively. They were 40.0 % and 18.3 % for slips not coated with rooting hormone or sterilized rooting media, respectively. Thus, for vegetative propagating (cutting) of medicinal hemp, sterilizing of rooting media and coating slips with rooting hormone will be essential to conducting the propagation process.
        4,000원
        20.
        2024.07 KCI 등재 구독 인증기관 무료, 개인회원 유료
        This study comprehensively investigates three types of graphite materials as potential anodes for potassium-ion batteries. Natural graphite, artificial carbon-coated graphite, and mesocarbon microbeads (MCMB) are examined for their structural characteristics and electrochemical performances. Structural analyses, including HRTEM, XRD, Raman spectroscopy, and laser particle size measurements, reveal distinct features in each graphite type. XRD spectra confirm that all graphites are composed of pure carbon, with high crystallinity and varying crystal sizes. Raman spectroscopy indicates differences in disorder levels, with artificial carbon-coated graphite exhibiting the highest disorder, attributed to its outer carbon coating. Ex-situ Raman and HRTEM techniques on the electrodes reveal their distinct electrochemical behaviors. MCMB stands out with superior stability and capacity retention during prolonged cycling, attributed to its unique spherical particle structure facilitating potassium-ion diffusion. The study suggests that MCMB holds promise for potassium-ion full batteries. In addition, artificial carbon-coated graphite, despite challenges in hindering potassium-ion diffusion, may find applications in commercial potassium-ion battery anodes with suitable coatings. The research contributes valuable insights into potassiumion battery anode materials, offering a significant extension to the current understanding of graphite-based electrode performance.
        4,600원
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