산화에틸렌은 IARC ‘Group 1’ 발암물질이나, 국내 노출 기준은 8시간 시간가중평균(이하 ‘TWA’) 1 ppm으로 단일화되어 있어 멸균기 개방 시 발생하는 단시간 고농도 노출(Peak exposure) 관리에 한계가 있다. 본 연구는 2024~2025년 서울 소재 37개 1·2차 로컬 의료기 관의 130개 시료를 대상으로 TWA, 최고노출기준(이하 ‘Ceiling’) 농도 및 피멸균물 포장 재 내 잔류 가스를 분석하였다. 분석 결과, TWA 기하평균은 0.2803 ppm으로 기준치 이내 였으나, Ceiling 기하평균은 3.0679 ppm, 지역 시료 최대치는 14.096 ppm으로 나타나 미 국 NIOSH 권고 기준(5 ppm)을 크게 상회하는 단시간 노출 위험이 확인되었다. 특히 피멸 균물 포장재 내부 잔류 농도는 최대 235.5 ppm에 달해 국내 TWA 기준의 235배를 초과하 는 심각한 수치를 보였다. 이러한 결과를 토대로 본 연구는 세 가지 측면에서 기대효과를 제시한다. 첫째, 실증 데이터를 근거로 국내 산화에틸렌 노출 기준에 STEL 또는 Ceiling을 추가하는 법·제도적 개선의 근거 자료로 활용될 수 있다. 둘째, 피멸균물 잔류 가스의 위험성을 제시함으로써, 멸균 종료 후 즉시 반출하는 관행을 개선하고 추가 환기 절차를 의무화하는 표준작업절차(SOP) 수립에 기여할 수 있다. 셋째, ESG 사회적 책임(S) 관점에 서 의료기관이 근로자 건강권 보호를 위한 선제적 공학적 관리 체계를 구축하는 데 실질 적인 정책 방향을 제시하여, 지속 가능한 의료기관 경영 모델 확립에 기여할 것으로 기대 된다.

Maintaining the postharvest freshness of Allium microdictyon Prokh, a highly perishable wild vegetable rich in bioactive compounds, remains a major challenge due to its susceptibility to ethylene-induced deterioration. This study aimed to develop an eco-friendly and efficient active packaging system using torrefied wood–based ethylene scavengers to extend the shelf life of A. microdictyon. Oak (Quercus variabilis) biomass was torrefied at 255 ℃ to produce porous, carbon-rich scavenger chips, which were integrated into polymer films composed of LDPE, HDPE, PP, and PVC. The ethylene absorption capacity and preservation performance of these composite packaging materials were evaluated over 30 days of storage at 27 ± 2 ℃ and 65 ± 5% relative humidity. The results demonstrated that torrefied wood effectively reduced internal ethylene concentration by over 70% in most polymer matrices, with HDPE + scavenger and LDPE + scavenger films showing the highest adsorption efficiencies. The treated samples exhibited significantly lower weight loss, higher moisture retention, and reduced chlorophyll degradation compared with the control (p < 0.05). Sensory and color analyses confirmed that ethylene scavenger–integrated packaging preserved the freshness and green coloration of A. microdictyon for up to 30 days, whereas control samples deteriorated rapidly. These findings highlight that torrefied wood is a safe and sustainable alternative to chemical absorbers, offering a promising bio-based solution for active packaging applications to enhance postharvest quality and reduce food waste in ethylene-sensitive crops.

Ethylene tar pitch (ETP), primarily derived from the residues of carbon black production and naphthalene purification in ethylene tar processing, is a polycyclic aromatic hydrocarbon with high carbon content and low ash content. It is considered a promising precursor for high-quality synthetic carbon materials. Thermal conversion is a critical step in the preparation of pitch-based carbon materials, as it largely determines the final structural quality of the carbon product. In this study, ETP was selected as the research subject, and a combination of analytical techniques, including group composition analysis, elemental analysis, Fourier Transform Infrared Spectroscopy (FTIR), polarized optical microscopy (POM), Raman spectroscopy, and X-ray diffraction (XRD) were employed to investigate the evolution of the average molecular structure and carbon microstructure during the thermal conversion process. The results indicate that with increasing thermal conversion temperature and duration, the degree of aromatic condensation in the ETP-derived products gradually increases. Simultaneously, the internal carbon microcrystals become more ordered and larger in size. Notably, when the thermal conversion temperature reaches 480 °C, the aromaticity index (Iar) sharply increases to 0.42, and anisotropic structures begin to appear under POM. This suggests that 480 °C is a critical temperature point at which ETP undergoes intensified thermal polycondensation and exhibits enhanced molecular reactivity. This study provides both theoretical and experimental support for the efficient utilization of ETP in the production of advanced carbon materials.

Shell & Tube type 중 “S”type 열교환기는 열팽창에 유리하여 산업현장에서 많이 사용하 고 있으나, 여러가지의 취성파괴 요인을 안고 있어 사고발생의 위험이 높다. 특히 “S”type 열교환기는 Floating Head를 Tube Sheet 반대편에서 잡아주는 Backing Device라는 필수적 인 부품을 사용하고 있는데, Backing Device는 형상적 특성, 사용유체, 온도환경, 기밀시 험 등 에 따라 여러 취성취약 요인을 갖고 있다. 본 연구는 지난 2022년 2월에 발생한 에틸렌 공장의 열교환기 폭발 사고의 사고원인 조사 에 기초하여, Backing Device 파단 부위와 파단면 분석, 강도 시뮬레이션 등을 통해 해당 사고에서 나타난 Backing Device의 취성 취약요인을 제시하였다. 본 연구를 통해 “S”type열교환기의 취성 취약성을 사업장의 안전관리를 위한 실무자료로 활용하고, 석유화학공장 에틸렌공정의 사고 예방을 통한 ESG 경영에 기여하길 기대한다.

The mass production of highly crystalline carbon nanotubes (CNTs) is highly demanded, yet achieving it remains challenging due to incomplete understanding of how synthetic parameters, except temperature, affect the crystallinity of CNTs. Notably, the choice of carbon precursor significantly influences CNT synthesis, but its impact on crystallinity remains unclear. Here, we employed a data analytics approach to examine the effect of carbon precursors on CNT crystallinity during their synthesis in a fluidized bed reactor. We compared ethylene, acetylene, and a mixture of these. Using Bayesian optimization (BO), we optimized synthesis conditions to maximize IG/ID of CNTs for each precursor. Key parameters considered were reaction temperature, precursor concentration, and hydrogen concentration. We conducted three separate BO processes to evaluate the effectiveness of each carbon precursor on CNT crystallinity. The results indicated no significant difference in IG/ID of CNTs among the carbon precursors. In addition, multiple linear regression analysis did not support a synergetic effect between acetylene and ethylene. Interestingly, contour plots demonstrated consistent relationships between synthesis parameters and IG/ID across different carbon precursors. This data analytics approach allowed us to successfully assess the impact of carbon precursors on the CNT crystallinity and analyze the relationship between synthesis parameters and CNT crystallinity.

Hyperoxaluria is a disorder associated with an increased risk of renal stones, one of the most common conditions. For people with hyperoxaluria, there are a limited number of effective therapeutic options. The aim of this study was to examine whether an oxalate-degrading enzyme, oxalate decarboxylase (OxdC), can inhibit crystallization of calcium oxalate (CaOx) in vitro, and whether it can prevent nephrolithiasis caused by CaOx induced by ethylene glycol (EG) in rats. When OxdC was applied at various concentrations to CaOx in vitro, there was a significant reduction in the crystallization of CaOx. The OxdC was found to inhibit crystal formation as well as the formation of crystals that had sharp edges. In animal experiments, rats that had been treated with EG showed impaired renal filtration functions, as well as increased deposition of CaOx crystals and the creation of kidney stones. It has been found that oral administration of OxdC to rats with chronic EG-induced nephrolithiasis that is characterized by CaOx intratubular crystal deposits with hyperoxaluria dramatically reduces the severity of the disease. The results of this study point to a potential therapeutic approach for treating human hyperoxaluria as well as CaOx nephrolithiasis that could be achieved by the oral administration of OxdC.

Carbon fibers of polyacrylonitrile (PAN) type were coated with nickel nanoparticles using a chemical reduction method in alkaline hydrazine bath. The carbon fibers were firstly heated at 400 °C and then chemically treated in hydrochloric acid followed by nitric acid to clean, remove any foreign particles and functionalized its graphitic surfaces by introducing some functional groups. The functionalized carbon fibers were coated with nickel to produce 10 wt% Cf/Ni nanocomposites. The uncoated heat treated and the nickel coated carbon fibers were investigated by SEM, EDS, FTIR and XRD to characterize the particle size, morphology, chemical composition and the crystal structure of the investigated materials. The nickel nanoparticles were successfully deposited as homogeneous layer on the surface of the functionalized carbon fibers. Also, the deposited nickel nanoparticles have quazi-spherical shape and 128–225 nm median particle size. The untreated and the heat treated as well as the 10 wt% Cf/Ni nanocomposite particles were further reinforced in ethylene vinyl acetate (EVA) polymer separately by melt blending technique to prepare 0.5 wt% Cf-EVA polymer matrix stretchable conductive composites. The microstructures of the prepared polymer composites were investigated using optical microscope. The carbon fibers as well as the nickel coated one were homogenously distributed in the polymer matrix. The obtained samples were analyzed by TGA. The addition of the nickel coated carbon fibers to the EVA was improved the thermal stability by increasing the thermal decomposition temperature Tmax1 and Tmax2. The electrical and the mechanical properties of the obtained 10 wt% Cf/Ni nanocomposites as well as the 0.5 wt% Cf-EVA stretchable conductive composites were evaluated by measuring its thermal stability by thermogravimetric analysis (TGA), electrical resistivity by four probe method and tensile properties. The electrical resistivity of the fibers was decreased by coating with nickel and the 10 wt% Cf/Ni nanocomposites has lower resistivity than the carbon fibers itself. Also, the electrical resistivity of the neat EVA is decreased from 3.2 × 1010 to 1.4 × 104 Ω cm in case of the reinforced 0.5 wt% Cf/Ni-EVA polymer composite. However, the ultimate elongation and the Young’s modulus of the neat EVA polymer was increased by reinforcing with carbon fibers and its nickel composite.

기후 변화에 따른 위험성은 전 세계적으로 오랜 기간 강조되고 있으며, 이를 극복하기 위한 노력은 해운분야에서도 국제해사 기구를 중심으로 이어지고 있다. 연소과정에서 발생한 매연을 제어하기 위하여 매연 생성 특성에 관한 연구는 필수적이다. 본 연구에서는 에틸렌 가스를 기반으로 한 대향류 확산화염에서 불활성 기체인 질소를 혼합하여 화염온도, 화염형태, 매연 생성 관련된 화학종의 상태변 화를 확인하기 위해 광소멸법과 화학반응 수치해석을 수행하였다. 연구 결과. 질소의 혼합비율이 증가함에 따라 화염온도 감소와 매연체 적분율 감소로 이루어졌다. 매연 입자가 분포하는 구간도 감소하였으며, 30% 이상 혼합비율이 높아지면 체적분율 감소율이 감소하였다. 매연 성장에 관여하는 화학종들의 몰분율도 감소하였다. HACA 반응 관련 화학종은 탄화수소 연료 비율에 따라 영향을 받으나, 홀수탄소 경로 관련 화학종은 탄화수소 연료 비율뿐만 아니라 화염온도 영향을 받는 것을 확인하였다.

Ethylene-mediated premature floral senescence influences the postharvest quality and longevity of rose flowers. In recent years, studies have unveiled the action of ethylene during the development and senescence of rose flowers. However, despite the evidence that ethylene is highly produced in ethylene-sensitive roses, there is not always a direct interrelationship between ethylene sensitivity and rose flower longevity. In addition, ethylene sensitivity and ethylene-related gene expressions in roses are still not clearly understood. In this review, we summarized and discussed ethylene synthesis and sensitivity, role of ethylene-related genes, and impacts of ethylene on the postharvest quality of cut roses. By combining the mechanism of ethylene biosynthesis and signaling with ethylene sensitivity, we also highlighted the potential use of ethylene inhibitors for ethylene control and to improve the postharvest quality of cut rose flowers. We believe that this review will provide sufficient information about ethylene biology in rose flowers and contribute in developing effective methods to extend the postharvest life of roses by preventing ethylene damage.