초임계 이산화탄소 조건에서 다중벽 탄소 나노튜브(MWCNT)에 공유결합으로 조합된 폴리(2-에티닐피리디 늄 염) 복합체를 제조하였다. 초기 반응 단계에서 MWCNT 표면에서 형성된 4차염화 2-에티닐피리디늄 염의 활성 화된 아세틸렌 삼중 결합이 MWCNT 표면에서 연속적으로 중합되어 폴리(2-에티닐피리디늄 염)이 공유결합으로 조 합된 MWCNT가 용이하게 제조되었다. MWCNT/폴리(2-에티닐피리디늄 염)의 전기 광학 및 전기화학적 특성을 측 정하고 분석하였다. 해당 복합체의 광발광 피크는 2.04 eV의 광자 에너지에 해당하는 610 nm에서 관찰되었다. SnO2:F/TiO2/N719 염료/고체 전해질/Pt 장치가 있는 준고체 DSSC를 MWCNT/P2EP로 제조하였는데, 이의 최대 에 너지 변환효율은 5.33%였다.

해당 연구는 산업 폐수에서 염료를 효율적으로 제거하기 위한 고급 박막 나노복합체(TFN) 기반 나노여과막을 개 발하여 효과적인 폐수 처리 방법을 제시합니다. 최근 연구의 동향을 보면, 나노카본, 실리카 나노스피어, 금속-유기 프레임워 크(MOF) 및 MoS2와 같은 혁신적인 재료를 포함하는 TFN 막의 제조에 중점을 둡니다. 주요 목표는 염료 제거 효율을 향상 시키고 오염 방지 특성을 개선하며 염료/염 분리에 대한 높은 선택성을 유지하는 것입니다. 이 논문은 넓은 표면적, 기계적 견고성 및 특정 오염 물질 상호 작용 능력을 포함하여 이러한 나노 재료의 뚜렷한 이점을 활용하여 현재 나노여과 기술의 제 한을 극복하고 물 처리 문제에 대한 지속 가능한 솔루션을 제공하는 것을 목표로 합니다.

The pursuit of sustainable and durable cementitious composites has led to a growing interest in alternative materials that can improve mechanical performance while reducing CO2 emissions. Nanomaterials, in particular, offer promising avenues due to their unique properties, including high surface area to volume ratio and increased reactivity. This study investigates the efficacy of Cellulose Nanofibers (CNF) in enhancing the durability of mortar exposed to sulfate attacks and alkali-silica reactions (ASR). Both MgSO4 and Na2SO4 solutions were employed to simulate sulfate attacks, while the role of CNF in mitigating ASR was also evaluated. Results indicate that CNF incorporation positively impacts the resistance of mortar against sulfate attacks and ASR, paving the way for eco-friendly and durable cement-based structures with extended service life.

The significance of this study lies in addressing critical issues prevalent in the worldwide construction sector, particularly concerning the durability and sustainability of cement-based materials. Plain cement composites commonly suffer from deficiencies in tensile strength and strain capacity, resulting in the formation of nano-cracks under relatively low tensile loads. These nano- cracks pose a significant challenge to the longevity and resilience of cement matrices, contributing to structural degradation and reduced service life of infrastructure. To mitigate these challenges, the integration of cellulose nanofibers (CNF) as reinforcements in cement composites presents a promising solution. CNF, renowned for their exceptional material properties including high stiffness, tensile strength, and corrosion resistance, offer the potential to significantly enhance the mechanical performance and durability of cement-based materials. Through systematic experimentation, this study investigates the effects of CNF reinforcement on the mechanical properties of cement composites. By leveraging ultrasonically dispersion techniques, CNF extracted from bamboo, broad leaf, and kenaf are uniformly dispersed within the cement matrix at varying concentrations. Compressive and flexural tests are subsequently conducted to evaluate the impact of CNF on the strength characteristics of the cement composites. By elucidating the efficacy of CNF reinforcement through rigorous experimentation, this study aims to provide valuable insights into the development of construction materials with improved durability and sustainability. Ultimately, this research contributes to addressing critical challenges in the construction industry, offering potential solutions to enhance the performance and longevity of cement-based infrastructure.

다양한 원인으로 콘크리트 구조물에 하중이 작용되며, 이에 대한 적절한 대응이 이루어지지 않으면 구조물에 열화가 발생하고, 붕괴와 같은 대규모 재난을 초래할 수 있다. 구조물에 발생하는 하중을 감 지하는 연구는 지속적으로 이루어지고 있지만, 안전성 모니터링을 위한 혁신적인 시스템에는 여전히 부족함이 존재한다. 탄소나노튜브/폴리우레탄 복합체는 다양한 공학 분야에서 구조물 건전성 모니터링 을 위한 센서로 활용되어 센싱 효과가 뛰어난 것으로 알려져 있다. 따라서 본 연구에서는 다양한 공학 분야에서 구조물 건전성 모니터링 센서로 활용되고 있는 탄소나노튜브/폴리우레탄 복합체를 제작하여 모니터링 시스템을 개발하였다. 다양한 하중에 대한 센싱 성능을 파악하기 위해 인장, 압축, 충격 시험 을 진행하였고, 동시에 센서의 전기적 변화를 분석하였다. 추가적으로 본 센서가 구조물 표면에 적용 됨에 따라 온도, 습도와 같은 환경적 영향성을 분석하여 활용 가능성을 평가하였다. 또한, 최대 48행, 48열의 다중 계측이 가능한 IoT 기반 다중 모니터링 시스템을 개발하고, 이를 구조물에 적용된 센서 와 연계하여 스마트 모니터링 시스템으로서의 성능을 평가하였다. 이를 통해 탄소나노튜브/폴리우레탄 복합체 기반 센서는 구조물 하중 감지 시스템으로 활용이 가능할 것으로 판단되었다.

Composite-based piezoelectric devices are extensively studied to develop sustainable power supply and selfpowered devices owing to their excellent mechanical durability and output performance. In this study, we design a leadfree piezoelectric nanocomposite utilizing (Ba0.85Ca0.15)(Ti0.9Zr0.1)O3 (BCTZ) nanomaterials for realizing highly flexible energy harvesters. To improve the output performance of the devices, we incorporate porous BCTZ nanowires (NWs) into the nanoparticle (NP)-based piezoelectric nanocomposite. BCTZ NPs and NWs are synthesized through the solidstate reaction and sol-gel-based electrospinning, respectively; subsequently, they are dispersed inside a polyimide matrix. The output performance of the energy harvesters is measured using an optimized measurement system during repetitive mechanical deformation by varying the composition of the NPs and NWs. A nanocomposite-based energy harvester with 4:1 weight ratio generates the maximum open-circuit voltage and short-circuit current of 0.83 V and 0.28 A, respectively. In this study, self-powered devices are constructed with enhanced output performance by using piezoelectric energy harvesting for application in flexible and wearable devices.

상변화 물질(PCM)은 상전이 동안 에너지를 흡수하거나 방출할 수 있는 잠열 저장 물질로 활용된다. 최근 수십 년 동 안, 연구자들은 다양한 온도 적용을 위한 건설 물질로의 다양한 PCM의 통합을 탐구해 왔다. 그러나, PCM을 통합하는 콘크리트 의 기계적 및 열적 반응은 통합 방법에 의해 영향을 받는다. PCM을 콘크리트에 추가하기 위한 여러 기술이 제안되었다. 그럼 에도 불구하고, 콘크리트에 마이크로 캡슐화 PCM(m-PCM)의 통합은 종종 기계적 강도의 상당한 감소를 초래한다. 기존 콘크리 트에 m-PCM의 추가와 관련된 한계를 극복하기 위해, 예외적인 강도 및 내구성 특성으로 인해 초고성능 시멘트 복합체(UHPCC) 가 선호된다. 따라서, 본 연구에서는 기존 기술의 단점을 해결하기 위해 PCM을 통합한 신규 나노 엔지니어링 UHPCC를 개발하 였다. 또한, 시멘트 복합체의 기계적 및 열적 성능을 향상시키기 위해 다중 벽 탄소 나노튜브(MWCNT)를 추가하였다. 결과는 MWCNT의 포함이 기계적 성능을 향상시켰을 뿐만 아니라 시멘트 복합체의 열적 성능을 향상시켰다는 것을 보여 주었다.

Inorganic-organic composites find extensive application in various fields, including electronic devices and light-emitting diodes. Notably, encapsulation technologies are employed to shield electronic devices (such as printed circuit boards and batteries) from stress and moisture exposure while maintaining electrical insulation. Polymer composites can be used as encapsulation materials because of their controllable mechanical and electrical properties. In this study, we propose a polymer composite that provides good electrical insulation and enhanced mechanical properties. This is achieved by using aluminum borate nanowhiskers (ABOw), which are fabricated using a facile synthesis method. The ABOw fillers are created via a hydrothermal method using aluminum chloride and boric acid. We confirm that the synthesis occurs in various morphologies based on the molar ratio. Specifically, nanowhiskers are synthesized at a molar ratio of 1:3 and used as fillers in the composite. The fabricated ABOw/epoxy composites exhibit a 48.5% enhancement in mechanical properties, similar to those of pure epoxy, while maintaining good electrical insulation.

In this study, a new type of composite material combined with carbonyl iron, a relatively strong ferromagnetic material, was prepared to overcome the current application limitations of Prussian blue, which is effective in removing radioactive cesium. The surface of the prepared composite was analyzed using SEM and XRD, and it was confirmed that nano-sized Prussian Blue was synthesized on the particle surface. In order to evaluate the cesium removal ability, 0.2 g of the composite prepared for raw cesium aquatic solution at a concentration of 5 μg was added and reacted, resulting in a cesium removal rate of 99.5 %. The complex follows Langmuir’s adsorption model and has a maximum adsorption amount (qe) of 79.3 mg/g. The Central Composite Design (CCD) of the Response Surface Method (RSM) was used to derive the optimal application conditions of the prepared composite. The optimal application conditions achieved using Response optimization appeared at a stirring speed of pH 7, 17.6 RPM. The composite manufactured through this research is a material that overcomes the Prussian Blue limit in powder form and is considered to be excellent economically and environmentally when applied to a cesium removal site.

Tin-antimony sulfide nanocomposites were prepared via hydrothermal synthesis and a N2 reduction process for use as a negative electrode in a sodium ion battery. The electrochemical energy storage performance of the battery was analyzed according to the tin-antimony composition. The optimized sulfides exhibited superior charge/discharge capacity (770 mAh g-1 at a current density of 100 mA g-1) and stable lifespan characteristics (71.2 % after 200 cycles at a current density of 500 mA g-1). It exhibited a reversible characteristic, continuously participating in the charge-discharge process. The improved electrochemical energy storage performance and cycle stability was attributed to the small particle size, by controlling the composition of the tin-antimony sulfide. By optimizing the tin-antimony ratio during the synthesis process, it did not deviate from the solubility limit. Graphene oxide also acts to suppress volume expansion during reversible electrochemical reaction. Based on these results, tin-antimony sulfide is considered a promising anode material for a sodium ion battery used as a medium-to-large energy storage source.

Despite the long history of mushroom use, studies examining the genetic function of mushrooms and the development of new varieties via bio-molecular methods are significantly lacking compared to those examining other organisms. However, owing to recent developments, attempts have been made to use a novel gene-editing technique involving CRISPR/Cas9 technology and genetic scissors in mushroom studies. In particular, research is actively being conducted to utilize ribonucleoprotein particles (RNPs) that can be genetically edited with high efficiency without foreign gene insertion for ease of selection. However, RNPs are too large for Cas9 protein to pass through the cell membrane of the protoplasmic reticulum. Furthermore, guide RNA is unstable and can be easily decomposed, which remarkably affects gene editing efficiency. In this study, nanoparticles were used to mitigate the shortcomings of RNP-based gene editing techniques and to obtain transformants stably. We used Lentinula edodes (shiitake mushroom) Sanjo705-13 monokaryon strain, which has been successfully used in previous genome editing experiments. To identify a suitable osmotic buffer for the isolation of protoplast, 0.6 M and 1.2 M sucrose, mannitol, sorbitol, and KCl were treated, respectively. In addition, with various nanoparticle-forming materials, experiments were conducted to confirm genome editing efficiency via the formation of nanoparticles with calcium phosphate (CaP), which can be bound to Cas9 protein without any additional amino acid modification. RNPs/NP complex was successfully formed and protected nuclease activity with nucleotide sequence specificity.