식품 포장 분야에서 바이오센서와 바이오폴리머 기반 나 노복합체, 즉 바이오나노복합체의 통합이 점차 산업 전문 가들에 의해 인식되고 있으며, 이는 식품의 품질과 안전 에 대한 우려가 증가함에 따라 주도되고 있습니다. 식품 포장에 내장된 바이오센서는 포장된 상품의 미생물에 의 한 변질을 지속적으로 모니터링함으로써 식품의 완전성을 유지하는 핵심 요소로 업계를 변화시킬 준비가 되어 있다. 동시에, 탁월한 기계적, 열적, 광학적, 항균적 특성으로 인 해 바이오폴리머 기반 나노복합체의 연구와 적용이 크게 확대되었다. 이러한 특성은 이들을 혁신적인 포장 솔루션 에 적합한 주요 재료로 만든다. 그러나 지능형 식품 포장 시스템 발전에 바이오센서와 바이오나노복합체를 사용하 는 잠재적인 장애물과 전망을 탐구하는 것은 아직 충분하 지 않다. 바이오나노복합체와 바이오센서의 융합을 제안 하는 것은 스마트 포장 산업을 재정의하는 획기적인 단계 로, 이 기술들을 더 깊이 이해하여 지속 가능하고 경제적 으로 실행 가능한 스마트 포장 옵션의 개발을 촉진할 필 요성을 강조한다. 이 리뷰는 바이오센서와 바이오나노복 합체에 대한 기존 연구와 개발 동향을 철저히 검토하고, 가까운 미래에 스마트 식품 포장 산업에서 진전을 이끌어 낼 앞으로의 도전과 기회를 강조하는 데 전념하고 있다.
Interim dry cask storage systems comprising AISI 304 or 316 stainless steel canisters have become critical for the storage of spent nuclear fuel from light water reactors in the Republic of Korea. However, the combination of microstructural sensitization, residual tensile stress, and corrosive environments can induce chloride-induced stress corrosion cracking (CISCC) for stainless steel canisters. Suppressing one or more of these three variables can effectively mitigate CISCC initiation or propagation. Surface-modification technologies, such as surface peening and burnishing, focus on relieving residual tensile stress by introducing compressive stress to near-surface regions of materials. Overlay coating methods such as cold spray can serve as a barrier between the environment and the canister, while also inducing compressive stress similar to surface peening. This approach can both mitigate CISCC initiation and facilitate CISCC repair. Surface-painting methods can also be used to isolate materials from external corrosive environments. However, environmental variables, such as relative humidity, composition of surface deposits, and pH can affect the CISCC behavior. Therefore, in addition to research on surface modification and coating technologies, site-specific environmental investigations of various nuclear power plants are required.
호접란은 세계적으로 분화뿐만 아니라 절화로도 판매되는 주 요 화훼작물이다. 상업적 종묘 대량생산은 조직배양 기술에 의 해 이루어지고 있으나 우리나라는 아직까지 균일하고 우수한 발근묘 생산 기술이 확립되지 않았다. 생육이 고르고 우수한 발근 배양묘를 생산하기 위한 적정 배양 신초수를 찾기 위해 용적 500mL 유리 배양병에 호접란 2품종(‘Lovely Angel’과 ‘UniVivace’)의 신초를 1, 4, 7, 10개씩 배양한 후 3개월에 지상부 및 지하부 초기 생육 특성을 조사한 결과, 7개의 신초를 배양하였을 때 신초의 생육이나 뿌리 유도 및 생육에 효과적이 었다. 또한, 배양병 재질이 발근묘 생육에 미치는 영향을 확인하 고자 용적이 500mL로 동일한 유리 배양병과 플라스틱 배양병 에 신초 7개 배양 3개월 후 2품종의 생육 특성을 비교한 결과, 2품종 모두 플라스틱 배양병 보다는 유리 배양병이 유의적으로 생육에 효과적인 것으로 확인되었다. 기내 발근묘 생산을 위한 배양병 재질의 영향은 이후까지 지속적으로 영향을 미치는 것으 로 확인되었다. 결론적으로, 균일한 호접란 발근묘 생산은 플라 스틱 재질보다는 유리병 재질의 배양병이 적합하며, 특히, 용적 이 500mL인 유리 배양병의 경우 신초를 7개(묘당 재식면적 5.4㎠) 이내로 배양하는 것이 바람직한 것으로 확인되었다.
최근 국내외 화장품과 식품산업에서 다양하게 사용되어 지고 있는 콜라겐 단백질 제품은 점차 그 용도와 특성에 따라 보다 고도화, 기능화 되어 가고 있다. 피부 건강의 지표인 콜라겐은 다양한 용도로 개발되어 사용되고 있으 며, 콜라겐의 소비가 증가함에 따라 용도에 적합한 최적 화된 콜라겐 제품의 개발이 중요한 연구 분야이다. 특히 여러 기업과 연구기관들에 의해서 콜라겐의 흡수율을 높 이기 위한 다양한 노력이 이루어지고 있다. 따라서 본 연 구에서는 프란즈(Franz) 세포 시스템을 이용하여 국내에서 판매되는 다양한 분자량별 콜라겐 제품의 경피 및 구강 상피세포 투과성을 비교하였다. 그 결과, 피부 표피/진피 조직과 비교하여 구강점막 조직의 콜라겐 흡수율이 분자 량 500달톤과 1,000달톤의 경우 모두 통계적으로 유의하 게(각각 약 10배, 2배) 높은 것으로 확인되었다. 또한, 분 자량별 구강점막 조직 흡수율을 비교한 결과, 분자량 500 달톤의 콜라겐이 분자량 1,000달톤 제품에 비해 흡수율이 2-3배 증가함을 확인하였다. 분자량 500달톤의 경우 Cmax 와 AUCt 값이 가장 높게 나타났으며, 피부 표피/진피 세 포에 비해 구강점막세포 시험군의 모든 지표가 높은 것으 로 나타났다. 본 연구 결과는 피부 흡수보다는 구강 점막 세포를 통한 콜라겐의 흡수방법이 콜라겐 체내 흡수증가 에 유효한 수단임을 시사하며, 분자량 1,000달톤 이하에서 도 보다 더 작은 500달톤의 저분자 콜라겐의 흡수율이 증 가되는 것으로 보아 콜라겐의 분자량이 흡수율 증가의 주 요한 요소임을 확인할 수 있었다.
Carbon nanomaterials (CNMs) have been the subject of extensive research for their potential applications in various fields, including photovoltaics and medicine. In recent years, researchers have focused their attention on CNMs as their high electrical conductivity, low cost, and large surface area are promising in replacing traditional platinum-based counter electrodes in dye-sensitized solar cells (DSSC). In addition to their electrical properties, CNMs have also displayed antibacterial activity, making them an attractive option for medical applications. The combination of CNMs with metal oxides to form composite materials represents a promising approach with significant potential in various fields, including energy and biology. Here, we introduce porous carbon nanospheres (PCNS) derived from Cocos nucifera L. and its ZnO composite (PCNS/ZnO) as an alternative material, which opens up new research insights for platinum-free counter electrodes. Bifacial DSSCs produced using PCNS-based counter electrodes achieved power conversion efficiencies (PCE) of 3.98% and 2.02% for front and rear illumination, respectively. However, with PCNS/ZnO composite-based counter electrodes, the efficiency of the device increased significantly, producing approximately 5.18% and 4.26% for front and rear illumination, respectively. Moreover, these CNMs have shown potential as antibacterial agents. Compared to PCNS, PCNS/ZnO composites exhibited slightly superior antibacterial activity against tested bacterial strains, including gram-positive Bacillus cereus (B. cereus) and Staphylococcus aureus (S. aureus), and gram-negative Vibrio harveyi (V. harveyi) and Escherichia coli (E. coli) with MIC values of 125, 250, 125, and 62.5 μg/ml, respectively. It is plausible that the outcomes observed were influenced by the synergistic effects of the composite material.
Exploring highly efficient, and low-cost oxygen reduction reaction (ORR) and oxygen evolution reaction (OER) catalysts is extremely vital for the commercial application of advanced energy storage and conversion devices. Herein, a series of graphene-like C2N supported TMx@C2N, (TM = Fe, Co, Ni, and Cu, x = 1, 2) single- and dual-atom catalysts are designed. Their catalytic performance is systematically evaluated by means of spin-polarized density functional theory (DFT) computations coupled with hydrogen electrode model. Regulating metal atom and pairs can widely tune the catalytic performance. The most promising ORR/OER bifunctional activity can be realized on Cu2@ C2N with lowest overpotential of 0.46 and 0.38 V for ORR and OER, respectively. Ni2@ C2N and Ni@C2N can also exhibit good bifunctional activity through effectively balancing the adsorption strength of intermediates. The correlation of reaction overpotential with adsorption free energy is well established to track the activity and reveal the activity origin, indicating that catalytic activity is intrinsically governed by the adsorption strength of reaction intermediates. The key to achieve high catalytic activity is to effectively balance the adsorption of multiple reactive intermediates by means of the synergetic effect of suitably screened bimetal atoms. Our results also demonstrate that lattice strain can effectively regulate the adsorption free energies of reaction intermediates, regarding it as an efficient strategy to tune ORR/OER activity. This study could provide a significant guidance for the discovery and design of highly active noble-metal-free carbon-based ORR/OER catalysts.
In this paper, iron ore tailings (IOT) were separated from the tailings field and used to prepare cement stabilized macadam (CSM) with porous basalt aggregate. First, the basic properties of the raw materials were studied. Porous basalt was replaced by IOT at ratios of 0, 20 %, 40 %, 60 %, 80 %, and 100 % as fine aggregate to prepare CSM, and the effects of different cement dosage (4 %, 5 %, 6 %) on CSM performance were also investigated. CSM’s durability and mechanical performance with ages of 7 d, 28 d, and 90 d were studied with the unconfined compression strength test, splitting tensile strength test, compressive modulus test and freeze-thaw test, respectively. The changes in Ca2+ content in CSM of different ages and different IOT ratios were analyzed by the ethylene diamine tetraacetic acid (EDTA) titration method, and the micro-morphology of CSM with different ages and different IOT replaced ratio were observed by scanning electron microscopy (SEM). It was found that with the same cement dosage, the strengths of the IOT-replaced CSM were weaker than that of the porous basalt aggregate at early stage, and the strength was highest at the replaced ratio of 60 %. With a cement dosage of 4 %, the unconfined compressive strength of CSM without IOT was increased by 6.78 % at ages from 28 d to 90 d, while the splitting tensile strength increased by 7.89 %. However, once the IOT replaced ratio reached 100 %, the values increased by about 76.24 % and 17.78 %, which was better than 0 % IOT. The CSM-IOT performed better than the porous basalt CSM at 90 d age. This means IOT can replace porous basalt fine aggregate as a pavement base.
High-entropy alloys (HEAs) have been reported to have better properties than conventional materials; however, they are more expensive due to the high cost of their main components. Therefore, research is needed to reduce manufacturing costs. In this study, CoCrFeMnNi HEAs were prepared using metal injection molding (MIM), which is a powder metallurgy process that involves less material waste than machining process. Although the MIM-processed samples were in the face-centered cubic (FCC) phase, porosity remained after sintering at 1200°C, 1250°C, and 1275°C. In this study, the hot isostatic pressing (HIP) process, which considers both temperature (1150°C) and pressure (150 MPa), was adopted to improve the quality of the MIM samples. Although the hardness of the HIP-treated samples decreased slightly and the Mn composition was significantly reduced, the process effectively eliminated many pores that remained after the 1275°C MIM process. The HIP process can improve the quality of the alloy.
This review explores the potential of pillared bentonite materials as solid acid catalysts for synthesizing diethyl ether, a promising renewable energy source. Diethyl ether offers numerous environmental benefits over fossil fuels, such as lower emissions of nitrogen oxides (NOx) and carbon oxides (COx) gases and enhanced fuel properties, like high volatility and low flash point. Generally, the synthesis of diethyl ether employs homogeneous acid catalysts, which pose environmental impacts and operational challenges. This review discusses bentonite, a naturally occurring alumina silicate, as a heterogeneous acid catalyst due to its significant cation exchange capacity, porosity, and ability to undergo modifications such as pillarization. Pillarization involves intercalating polyhydroxy cations into the bentonite structure, enhancing surface area, acidity, and thermal stability. Despite the potential advantages, challenges remain in optimizing the yield and selectivity of diethyl ether production using pillared bentonite. The review highlights the need for further research using various metal oxides in the pillarization process to enhance surface properties and acidity characteristics, thereby improving the catalytic performance of bentonite for the synthesis of diethyl ether. This development could lead to more efficient, environmentally friendly synthesis processes, aligning with sustainable energy goals.
This research introduces an innovative approach for evaluating the degree of densification of carbon nanotube (CNT) sheets produced through direct spinning and subsequently treated with organic solvent (specifically ethanol). Analysis of the morphological features of the CNT sheets from the FE-SEM image affirms that the sheet’s structure becomes more densified following the treatment. Based on this, the treated CNT sheet was comprehensively evaluated using Raman spectroscopy. The results indicate a downward shift in the G′ band, signifying the densification of the CNT sheet’s structure due to the C–C bond weakening by the cohesive force. Following ethanol treatment, the CNT sheet exhibited enhanced electrical conductivity and tensile strength, measuring approximately 1.7 × 105 S m− 1 and 138.7 MPa, respectively, a remarkable improvement of roughly 300% compared to the untreated CNT sheet. This study underscores the efficacy of Raman spectroscopy as a powerful tool for assessing the densification of CNT sheets.
Traditional culture contributes to the diversification of modern fashion design and the inheritance of local cultural identity. This study aims to identify the characteristics of traditional handicrafts reflected in modern fashion design in India. For this purpose, it focused on Sabyasachi Mukherjee, Manish Malhotra, and Ritu Kumar, who are currently leading the Indian fashion design field. The methodology involved conducting literature research and analyzing case studies. In the literature, the techniques of Indian traditional crafts such as embroidery, dyeing, and weaving were examined and five design elements of traditional crafts were defined. Through content analysis of 30 images from the three designers’ Instagram accounts, the design characteristics of traditional handicrafts expressed in contemporary Indian fashion design were derived: cultural inheritance using traditional Indian clothing items, traditional materials and practices applied to contemporary clothing, craftsmanship that artistically improves complex details using embroidery techniques, various combinations based on the traditional meaning of colors, and narrative expression using patterns containing India’s cultural identity. Incorporating these traditional handicrafts into fashion design, closely linked to everyday life, aids in conveying and enhancing their significance. The cases demonstrate the successful integration of conservation into contemporary fashion design. This study sheds light on the application of traditional culture in modern fashion design.