도로에서 소음저감에 대한 대책으로 방음벽, 포장 개선, 차량 속도 제한 등 여러 가지 대책이 제기되고 있으며 최근에는 차세대 표면처리 공법(Next Generation Concrete Surface, NGCS)이 사용되고 있다. 이러한 NGCS는 표면을 그라인딩 후 그루빙 공정을 진행하게됨에 따라 포장두께 감소 및 ITZ(Interfacial Transition Zone)의 표면 노출에 따른 내구성 감소가 발생할 수 있다. 이러한 내구성 감소는 교면포장에서 발생 시 안정성에 크리티컬한 영향을 미치게 됨에 따라, 본 연구는 교면포장에 주로 사용되는 라텍스 개질 콘크리트 (Latex-Modified Concrete, LMC)에 NGCS 적용 시 발생할 수 있는 내구성 감소 중 염해에 관한 연구를 진행하였다. 실제 공용 중인 LMC 교면포장의 현장 코어와 라텍스 혼입율(10, 15, 20%)에 따른 실내 배합을 진행하였으며 NGCS를 시험편에 적용하기 위하여 도로공사 표면처리공법 시방서를 기준에 따른 NGCS 모사 공법을 적용하여 염해 내구성 평가를 진행하였다. 시험 결과 현장코어의 경우 높은 수밀성과 염해저항성을 가지고 있어 NGCS 처리 시 뚜렷한 염해 내구성 저하가 나타나지 않았지만 상대적으로 낮은 수밀성을 가진 LMC 실내 배합의 경우 NGCS 적용 시 소폭의 염해 내구성이 감소함을 확인하였다.

본 연구에서는 상용 폴리염화비닐을 개질하여 두 종류의 PVC 기반 이온교환용 고분자를 성공적으로 제조하였다. 이후 개질된 두 이온교환 고분자를 활용한 전기방사 공정과 열 압착 공정을 거쳐 2차원 계면(2D-PVC-BPM)과 3차원 접합부 (3D-PVC-BPM)를 갖는 바이폴라막(BPM)을 제조하였다. 제조된 3D-PVC-BPM은 2D-PVC-BPM에 비해 우수한 물 분해 효율 및 안정성을 보였다. 구체적으로, 300 mA cm-2의 고전류 밀도에서 3D-PVC-BPM은 2D-PVC-BPM가 나타낸 전위보다 4.4 V 낮은 8.05 V의 막 전위를 나타냈다. 더욱이, PVC 주쇄가 가진 내화학성 덕분에 3D-PVC-BPM은 가혹한 조건에서도 높은 화 학적 안정성을 보였고, 이는 4 M H2SO4 및 4 M NaOH 용액에 28일간 침지한 후 관측된 질량 손실이 각각 2.8%와 2.1%에 그친 것을 통해 입증되었다. 끝으로, 3차원 접합부가 3D-PVC-BPM에 맞물림(interlocking) 효과와 넓은 계면면적을 제공해준 덕분에 3D-PVC-BPM의 인장 강도는 36 MPa를 초과했고 신장률 또한 약 50%에 이르는 등 우수한 기계적 물성을 나타냈다.

This study aims to reduce the use of chloride-based deicers by analyzing their residual quantities on road surfaces. The freezing conditions of road surfaces were quantitatively defined using needles of consistent weight and diameter, and indoor experiments were conducted to observe changes in surface conditions caused by residual deicers under various temperatures. To validate the equipment, a deicer currently used in Korea was applied to granite plates, and the correlation between the application rates and salinity measurements obtained using the SOBO3+ device was analyzed. Subsequently, the device was employed to measure salinity changes over time by assessing the variations in residual deicer quantities on roads with different traffic volumes and application rates. To identify issues in current reapplication methods, the deicer was reapplied at 2-h intervals, and the resulting changes in salinity were monitored. Results of laboratory experiments revealed that the interval for surface state changes decreases with the temperature despite increased deicer usage, and that similar surface change patterns are presented at higher (-2 °C, -4 °C) and lower temperatures (-6 °C, -10 °C). Across all temperatures, the coefficient of determination for the surface-change graph is approximately 0.90. Equipment verification shows that 10% of sodium chloride is underestimated, whereas aqueous calcium chloride is accurately measured and no correlation is indicated between measurement accuracy and road surface temperature. Field experiments confirmed that the deicer dispersion rates increases with the traffic volume. Furthermore, the final salinity increases after the reapplication of the deicer, except in cases of high traffic volume, and that repeated applications with reduced spray amounts are more effective than single applications with higher spray amounts under low traffic conditions. Based on the findings obtained, a plan to reduce deicer usage is proposed. Future research should incorporate additional variables that affect deicer loss and surface condition changes to further refine the results.

This study aims to propose an improvement of fire safety management plans for buildings, such as apartment complexes and schools, within a 10 km radius of industrial complexes. It utilizes an off-site consequence analysis program to reflect the toxic impact on national industrial complexes and surrounding areas. The ALOHA program was utilized to analyze the impact of toxicity due to a hydrogen chloride leak, a hazardous material. The results showed that the area with AEGL-2 and above ranged from 3.1 km to 10 km, the AEGL-3 area ranged from 1.9 km to 7.3 km. The ASET was measured to be between 3 and 24 minutes. Due to the impact of toxicity, it is necessary to prepare fire safety management plans for buildings, such as apartment complexes and schools that are within a 10 km radius from industrial complexes. These safety plans incorporate the hydrogen chloride risk assessment results, ASET, weather conditions, and coordination with the local community.

본 논문은 염해 환경에 노출된 CFRP Grid로 보강된 콘크리트 보의 휨 거동에 대한 실험적 연구를 보고한다. 실험을 위해 길 이 2,200 mm, 폭 250 mm, 높이 125 mm의 실험체가 제작되었다. 실험변수로 염화물 수용액의 종류(NaCl: 염화나트륨, CaCl2: 염화칼 슘), 사전 하중 가력의 유무 및 염화물 용액 침지 기간(40일, 120일)이 고려되었다. 제작된 실험체는 침지 후 3점 휨 실험이 수행되었다. 초기 균열 하중은 침지 40일 후 증가하였으나, 120일 이후 다시 감소하였다. 파괴 모드는 사전 하중 가력을 통해 균열이 발생되지 않은 실험체에서는 대부분 콘크리트 압축부가 파쇄되는 휨파괴 양상을 보였으며, 사전 하중 가력을 통해 균열이 발생된 실험체는 모두 Pull-Out 파괴가 발생되었다. 염화칼슘에 침지된 실험체에서는 120일 이후 약 10%의 극한하중의 감소가 나타났으며, 염화나트륨에 침지 된 실험체의 극한하중은 미미하게 증가하였다. 균열이 발생된 실험체에서는 모두 120일 이후 극한하중 및 처짐이 급격하게 감소되었다.

반응성 에시드 클로라이드인 트리멜리틱 안하이드라이드 클로라이드를 이용한 2-에티닐피리딘의 무촉매중 합을 통하여 트리멜리틱 부분을 측쇄로 갖는 이온성 공액구조 고분자를 합성하였다. 2-에티닐피리딘과 트리멜리틱 안하이드라이드 클로라이드를 1:1 몰비로 DMF 용매에서 반응시킨 결과 해당 공액구조 고분자를 높은 수율로 합성 할 수 있었다. 첫 번째 반응 단계에서 만들어진 단량체인 N-치환-2-에티닐피리디늄 염은 별도의 촉매 사용없이도 중합반응이 잘 진행되었다. NMR, IR, UV-visible 등의 분광분석기를 사용하여 합성 고분자의 구조를 분석한 결과 설계한 치환기를 갖는 공액구조 고분자가 합성되었음을 확인할 수 있었다. 합성 고분자의 전기-광학적 특성과 전기 화학적 특성을 측정하였다. 본 고분자는 자외선 영역뿐만 아니라 가시광선 영역에서 500 nm까지 넓은 흡수 피크 를 보였으며 PL 최대값은 539 nm에서 나타났다.

PURPOSES : Snow-removal performance is performed in this study to assess the feasibility of replacing calcium-chloride solution with sodium chloride solution at the minimum temperature of -5 ℃ during snowfall. METHODS : The atmospheric temperature distribution in Seoul was analyzed. The manufacturing, storage, and indoor melting performance of calcium-chloride and sodium-chloride solutions were evaluated, and on-site snow-removal performance was evaluated based on the solution type. RESULTS : According to the results of the melting performance test at -5°C, the melting capacity of the sodium chloride solution was expressed at a level exceeding 90% of that of the calcium chloride solution, indicating a similar melting performance between the two solutions. Additionally, based on the snow removal performance test using aqueous solutions, the snow removal performance of the sodium chloride solution was found to be approximately 96% compared to that of the calcium chloride solution, indicating minimal differences in snow removal performance due to changes in the type of solution. CONCLUSIONS : Similar snow-removal performance was achieved when the sodium chloride solution was used instead of calciumchloride aqueous solution at temperatures exceeding -5 ℃.

콘크리트는 우수하고 뛰어난 내구성에 의해 구조물 건설에 가장 많이 사용되는 재료 중 하나이다. 오늘날 급격한 경제의 발전 및 도시화 등에 의해 오늘날 구조물은 대형화 및 고층화되고 있다. 이에 따라 고강도, 고경량, 고내구 콘크리트 개발에 대한 다양한 연구가 진행되고 있다. 특히 나노소재가 첨 가된 콘크리트는 나노소재에 의해 미세공극이 충진되어 강도 및 내구성이 우수한 것으로 알려져있다. 그러나 기존 나노소재가 적용된 콘크리트는 단위중량이 높아 이를 구조물에 적용시 자중을 증가시키 는 단점이 있다. 이에 본 연구에서는 입자 직경이 10-100 μm이지만 입자 내부의 공극이 있어 단위 중량이 0.6t/m3인 Micro hollow sphere가 잔골재로 사용된 고경량, 고강도 콘크리트의 염화물 침투 특성을 평가하였다. 본 연구에서 사용된 실험변수로써 Micro hollow sphere의 잔골재 치환량(0%, 42%, 100%)가 고려되었으며, 이 시편의 단위중량은 각각 2.37 t/m3, 1.89 t/m3, 1.62 t/m3이다. Micro hollow sphere가 사용된 콘크리트의 염화물 침투 특성은 NT-Build 492 시험을 통해 평가되었다. 실 험결과 Micro hollow sphere 치환율이 0%, 42%, 100%인 실험체의 단위중량은 염화이온 확산계수는 각각 4.45 x10-13 m2/s, 2.57 x10-13 m2/s, 1.4x10-13 m2/s로 Micro hollow sphere 치환량이 증 가함에 따라 염화이온 침투 저항성이 증가하는 것으로 확인되었다. 따라서, Micro hollow sphere를 이용한다면 단위중량이 작으며 내구성이 큰 고경량, 고내구 콘크리트 배합이 가능할 것으로 판단된다.

Determination of Idarubicin (IDA) as an anthracycline derivative and extensively used treatment of leukemia was investigated by electrochemical method using carbon paste electrode (CPE) modified with NiO/SWCNTs nanocomposite and 1-ethyl-3-methylimidazolium chloride (EMCl). The NiO/SWCNTs nanocomposites and EMCl play an important catalytic role in improving the electron transfer process at surface of CPE to monitoring of IDA. Electrochemical method was used to investigation redox behavior of IDA at surface of the NiO/SWCNTs/EMCl/CPE. The oxidation signal of IDA amplified by modification of CPE by NiO/SWCNTs and EMCl was about 4.3 times and NiO/SWCNTs/EMCl/CPE detected IDA in concentration range of 0.001–160 μM with detection limit of 0.5 nM, respectively. The evaluation of analytical and recovery data confirms the mentioned method was completely validated and successfully employed for the determination of IDA in real samples.

Large-area porous carbon is easily produced for supercapacitors from polyvinylidene chloride (PVDC) and polyvinylidene fluoride (PVDF) precursors, composed of carbon backbone and attached heteroatoms. The released heteroatoms during pyrolysis leave the porous carbon. This study explored the activation of both precursors using chemical agents (ZnO, Mg(OH)2, and KOH) to develop carbon with multiple micropores and mesopores. The activation process and relevant precursors were studied to implement synthesized porous carbon as an electrode in supercapacitors. During the activation of PVDC-resin, ZnO served both as templates and activating agents, while Mg(OH)2 served only as a template, and KOH served as an activating agent. For activation of PVDF, ZnO acted as a template and activating agent, whereas Mg(OH)2 and KOH impeded activation owing to side reactions. Therefore, with the above chemical agents, PVDC-resin was converted to carbon with a higher surface area than PVDF. The porous carbon produced using PVDC-resin with KOH had the highest specific capacitance of 137 F g− 1 and rate performance of 79% at 50 mV s− 1 (vs. 5 mV s− 1) owing to the successful creation of micropores and mesopores. This study identifies optimal conditions for synthesizing porous carbon using polymer precursors and chemical agents for supercapacitors.

This study was conducted to reset the maximum residue limit (MRL) for didecyldimethylammonium chloride (DDAC) in broiler chickens. The disinfectant containing DDAC (10%, w/w) was diluted 160 times and evenly sprayed on the bodies of twenty-four broiler chickens at a rate of 15 mL per day per bird for 7 days. After the disinfectant treatment, tissue samples were collected from six broiler chickens at 0.25, 1, 3 and 5 days, respectively. Residual DDAC concentrations in poultry tissues were determined using LC-MS/MS. Correlation coefficient (0.99 >), the limits quantification (LOQ, 2.0~10.0 μg/kg), recoveries (86.9~118.6%), and coefficient of variations (<19.98%) were satisfied the validation criteria of Korean Ministry of Food and Drug Safety. In all tissues except for liver, DDAC was detected more than LOQ at 5 days after the disinfectant treatment. In liver tissues, DDAC was detected more than LOQ at 3 days after treatment. According to the European Medicines Agency’s guideline on determination of withdrawal periods, withdrawal period of DDAC in poultry tissues was established to 26 days. In conclusion, the developed analytical method is sensitive and reliable for detecting DDAC in poultry tissues. When DDAC disinfectant is sprayed on a poultry house in the presence of broiler chickens, it is necessary to keep the disinfectant from contacting the body of the livestock.

The design of buried underground flexible pipes proposed in domestic standards does not properly reflect changes in ground characteristics. Overseas standards suggest that pipe deflection must be considered while designing them. Therefore, in this study, the structural behavior of underground polyvinyl chloride pipes was investigated through experiments and the finite element analysis. In addition, when the pipe deflection occurred at 3% and 5%, the hydraulic characteristics of the polyvinyl chloride pipe showed a slight difference compared to the round pipe.

Background: Efficient gene editing technology is needed for successful knock-in. Homologous recombination (HR) is a major double-strand break repair pathway that can be utilized for accurately inserting foreign genes into the genome. HR occurs during the S/G2 phase, and the DNA mismatch repair (MMR) pathway is inextricably linked to HR to maintain HR fidelity. This study was conducted to investigate the effect of inhibiting MMR-related genes using CdCl2, an MMR-related gene inhibitor, on HR efficiency in HC11 cells. Methods: The mRNA and protein expression levels of MMR-related genes (Msh2, Msh3, Msh6, Mlh1, Pms2), the HR-related gene Rad51, and the NHEJ-related gene DNA Ligase IV were assessed in HC11 cells treated with 10 μM of CdCl2 for 48 hours. In addition, HC11 cells were transfected with a CRISPR/sgRNA expression vector and a knock-in vector targeting Exon3 of the mouse-beta casein locus, and treated with 10 μM cadmium for 48 hours. The knock-in efficiency was monitored through PCR. Results: The treatment of HC11 cells with a high-dose of CdCl2 decreased the mRNA expression of the HR-related gene Rad51 in HC11 cells. In addition, the inhibition of MMR-related genes through CdCl2 treatment did not lead to an increase in knock-in efficiency. Conclusions: The inhibition of MMR-related gene expression through high-dose CdCl2 treatment reduces the expression of the HR-related gene Rad51, which is active during recombination. Therefore, it was determined that CdCl2 is an inappropriate compound for improving HR efficiency.

Chloride is one of the most common threats to reinforced concrete (RC) durability. Alkaline environment of concrete makes a passive layer on the surface of reinforcement bars that prevents the bar from corrosion. However, when the chloride concentration amount at the reinforcement bar reaches a certain level, deterioration of the passive protection layer occurs, causing corrosion and ultimately reducing the structure’s safety and durability. Therefore, understanding the chloride diffusion and its prediction are important to evaluate the safety and durability of RC structure. In this study, the chloride diffusion coefficient is predicted by machine learning techniques. Various machine learning techniques such as multiple linear regression, decision tree, random forest, support vector machine, artificial neural networks, extreme gradient boosting annd k-nearest neighbor were used and accuracy of there models were compared. In order to evaluate the accuracy, root mean square error (RMSE), mean square error (MSE), mean absolute error (MAE) and coefficient of determination (R2) were used as prediction performance indices. The k-fold cross-validation procedure was used to estimate the performance of machine learning models when making predictions on data not used during training. Grid search was applied to hyperparameter optimization. It has been shown from numerical simulation that ensemble learning methods such as random forest and extreme gradient boosting successfully predicted the chloride diffusion coefficient and artificial neural networks also provided accurate result.

Sprouts have various health benefits. Specifically, wheat sprouts are rich in bioactive compounds, such as vitamins and polyphenols. Elicitation induces and enhances secondary metabolite biosynthesis in plants. Therefore, in this study, we investigated the effects of sodium chloride (NaCl) treatments on the growth profile, free amino acid content, and antioxidant activity of germinated wheat (Triticum aestivum). Wheat seeds were germinated at 20℃ for 10 days and treated with 0, 2, 4, 7.5, and 10 mM of NaCl 10 days before harvesting. Treating the soil bed with NaCl increased the nutritional component amounts, such as free amino acids and γ- aminobutyric acid. The chlorophyll a and b concentrations were the highest in the hydroponic system treated with 7.5 mM NaCl. In addition, the polyphenol and flavonoid contents of sprouts treated with 2 and 7.5 mM NaCl were 1.94 and 1.34 times higher than that of the control sprouts (0 mM NaCl, water only), respectively. These results suggest that 2 to 4 mM NaCl treatments improve the nutritional and food quality of wheat sprouts more than water only.

Corrosion is a natural, inevitable process, and is one of the world's most serious problems. Losses incurred due to corrosion are extremely expensive for society. Several technological strategies have been explored and implemented to address these losses. The use of inhibitors to prevent corrosion is a common and efficient method to reduce corrosion losses. This review covers Al and Al-composite corrosion inhibitors in chloride-containing solutions, because of their popularity in a broad array of industrial applications. A vast number of studies in the literature detail the common tendency of Al and Al-composites with reinforcements to deteriorate. Accordingly, it is worthwhile to employ inhibitors to protect them, as discussed in the present work. The emphasis is on selecting the smartest corrosion inhibitor and evaluating its performance. According to the study, the most commonly used corrosion inhibitors are 1,4-naphthoquinone (NQ), 1,5-naphthalene diol, 3-amino-1,2,4-triazole-5-thiol (ATAT), ammonium tetrathiotungstate, clotrimazole, amoxicillin, antimicrobial and antifungal drugs. Electrochemical impedance spectroscopy (EIS), potentiodynamic (PDP), and weight loss were among the most commonly used modern electrochemical technologies to test inhibitors’ efficacy under environmental conditions.