This study aimed to develop a powderization strategy using porcine by-products (kidney, liver, and heart) by evaluating the effects of raw material type, pretreatment, and additives (hydroxypropyl methyl cellulose P645 and gelatin) on powder characteristics. Powders from kidney tissue were analyzed for yield, particle structure, compressibility, and size distribution, based on the drying method and additive composition. The spray-dried sample with gelatin at 1:0.5 (w/w) showed 20.4% compressibility and the smallest, most uniform particles, indicating excellent flowability. Due to its superior structural stability, gelatin was selected over HPMC P645. Liver and heart samples that underwent enzymatic hydrolysis and the Maillard reaction were spray-dried with gelatin and assessed for yield and microstructure. The Alcalase-treated liver sample showed the highest yield. Surface analysis confirmed that gelatin formed a protective film enhancing particle stability. These findings suggest gelatin-based spray drying is effective for producing high-quality powders from protein-rich by-products.
Interest in high-permittivity dielectric materials suitable for classical systems has been increasing, and competition for commercial applications continues. However, despite the development of such dielectric materials, additional compositional improvements are still required to achieve low-temperature sintering that would allow co-firing with Cu internal electrodes in multilayer structures, and research in this area remains insufficient. In this study, we aimed to optimize a low-temperature sintering composition based on Pb0.94La0.06(Zr0.83Ti0.17)O3, which, in preliminary experiments, exhibited a dielectric constant above 1,300 at sintering temperatures exceeding 1300 °C. As the amount of Na ion addition increased, low-temperature sintering was effectively promoted. However, the dielectric constant simultaneously decreased. When K ions were further added to the Lead Lanthanum Zirconate Titanate (PLZT)+Na composition, the low-temperature sintering properties were maintained or improved, and the dielectric constant increased compared with Na-only addition. To precisely readjust the MPB region under the influence of large additive content, the Zr ion fraction was varied from 0.84 to 0.92. Within this range, the MPB composition was found to shift slightly as the Zr content increased. As a result, the optimal composition among the PLZT ceramics sintered at 950 °C was determined to be Zr 0.86, which exhibited a dielectric constant of approximately 900 and an energy storage density of about 2 J/cm3. These findings suggest that such a composition could be applicable for low-temperature co-firing with Cu electrodes in Multi-Layer Ceramic Capacitors (MLCCs) for classical systems.
This study investigates the changes in the surface characteristic, electrical and mechanical properties of copper foils electrodeposited in electrolytes with added various additives (Janus Green B (JGB), 3–mercapto–1–propane sulfonic acid (MPSA), Polyethylene glycol (PEG) and Chloride ion) under high current density. The main effect of additives on these properties was analyzed. In the group with added JGB, the crystal size on the surface became finer, and a homogeneous surface was observed. However, dented areas were observed, which decreased with an increase in chloride ions. When 100 ppm of PEG and 10 ppm of JGB were added, the fine dents on the surface increased. When a certain amount or more of additives were added, defects on the surface occurred due to competition between additives. The addition of JGB induced crystal growth in the direction of the (111) plane. Copper foils with excellent yield strength, tensile strength, and elongation could be obtained with an appropriate crystal size. The addition of JGB mainly affected crystal size and the direction of crystal growth, which is an important factor for controlling mechanical properties. PEG mainly affected elongation, and chloride ions had a primary effect on surface roughness, resistivity, and corrosion rate. Therefore, controlling additives is an effective way to significantly affect the manufacture of copper foil and produce various suitable properties in high demand.
Plastic wastes such as polyethylene terephthalate have recently been incorporated into coal as additives in coke manufacturing. Plastic waste results in the reduction of high-quality coal usage while protecting the environment. Using coal tar pitch as an additive in the coal blend causes an increase in fluidity during carbonization. The volatile matter released during carbonisation affects coal thermoplasticity, hence the carbon structural parameters. This paper investigates the role of polyethylene terephthalate and the mixture of polyethylene terephthalate and coal tar pitch on carbon structure formation during coal to coke transformation. The additives were blended with coking coal in 2, 3, 4, 5, and 10% wt. The results imply that incorporating coal tar pitch into the coal/ polyethylene terephthalate mixture improves the crystallite height of the resulting semi-coke. The addition of coal tar pitch and polyethylene teraphthalate blend to coking coal at a percentage below 5%wt. leads a positive impact on the crystallite height of the resulting coal char. The incorporation of coal tar pitch into the blend decreased the average interlayer spacing. At elevated temperatures, the polyethylene terephthalate in the blend causes an increase in the mean tortuosity. However, incorporating coal tar pitch into the blend led to about 3.3% decrease in mean tortuosity.
Sixty dried agricultural products were collected from February to July 2024. Among these, 16 samples were randomly purchased from large supermarkets and local markets in Gwangju, and 44 were obtained from online marketplaces. Only products labeled with phrases such as “No Food Additives” or “100% Raw Ingredients” were selected for analysis. The aims of this study were to determine the concentrations of sulfur dioxide, preservatives, artificial colorants, and toxic heavy metals (lead and cadmium) in dried agricultural products, assess their risk indices, and provide foundational data to establish relevant regulatory standards. The results revealed that sulfite compounds were detected in some samples, with the highest sulfur dioxide concentrations found in gourds (82.99- 1046.95 mg/kg), apricots (10.87-529.45 mg/kg), and konjac powder (23.59-475.92 mg/kg). The highest sulfur dioxide risk index was observed in persimmons, with values ranging from 4.74% to 16.61% for male and 6.26% to 26.84% for female consumers. Sweet potatoes followed, with risk index values of 6.87% and 11.29% for male and female consumers, respectively. All the samples exhibited sulfur dioxide risk indexes below 100%, indicating safety. No preservatives or artificial colorants were detected in any of the samples, suggesting that sulfites can be used as alternatives to preservatives in certain products. The concentrations of lead in dates (9.55-137.09 μg/kg) and gourds (10.76-49.14 μg/kg) and cadmium in gourds (16.36-51.76 μg/kg) were within safe limits, with risk indexes below 100%. This study provides crucial baseline data for evaluating the safety of dried agricultural products. Furthermore, it underscores the need for more comprehensive risk assessments that consider the interactions between sulfur dioxide, heavy metals, and consumption patterns. Lastly, it highlights the necessity of strengthening regulatory standards to better protect consumers.
지속저인 산업발전은 화석 연료사용과 에너지 사용을 증가시켰으며, 각 국가별 온실가스 배출은 증가하고 있는 실정이다. 국제사회는 지구 온난화 방지를 위해 1997년 교토 의정서를 채택하였고, 이산화탄소(CO2) 순 배출량 0을 목표로 하여 자체적으로 온실가스 배출 목표를 정하고 실천하고자 2015년 '파리기후변화협정'을 채택하였다. 우리나라는 2015년 '파리기후변화협정' 체결 후 2030년까지 2017년 총 배출량 대비 24.4 % 감축을 목표로 설정하였다.(외교부, 2020) 국내 사회 각 분야에서는 온실가스 감축을 위해 노력하고 있으며, 도로분야에서는 온실가스 저감을 위한 환경친화형 도로 설계와 시 공기술 개발을 위한 연구들이 검토되고 있다. 그 중 가열 아스팔트 혼합물 제조 시 사용되는 기존의 연료(중유, 벙커씨유, 정제유 등) 를 상대적으로 탄소배출량이 적은 연료(LPG, LNG)로 전환하거나, 플랜트 생산온도를 낮추어 사용되는 연료를 저감하는 방법 등 다양 한 연구를 진행하고 있다. 따라서 본 연구에서는 일반 가열 아스팔트 혼합물보다 약 50℃ 낮은 상태에서 생산할 수 있게 도와주는 탄소저감형 첨가제를 적용 한 저가열 아스팔트의 특성을 파악하고자 하였다. 기본 물성시험으로는 연화점, 신도, 회전점도를 시험하였으며, 공용성 등급 시험을 통하여 PG 등급을 확인하였다. 또한 기존에 상용화된 제품과 차이를 보기 위해, 첨가제가 투입되지 않은 일반 아스팔트와 중온 첨가 제 2종(고상형, 액상형)이 적용된 중온 아스팔트도 동일한 시험을 진행하였고, 저가열 아스팔트와 비교·분석 하였다.
This study was conducted to find a way to improve quality by observing changes in quality and microbial communities according to whether corn silage was treated with additives and the storage period, and to utilize them as basic research results. The experimental design was performed by 2˟4 factor desigh, and the untreated (CON), and the additive inoculated (ADD) silage were stored and fermented for 30 (TH), 60 (ST), 90 (NT), and 120 (OHT) days, with each condition repeated 3 times. There was no change in the nutrient content of corn silage according to additive treatment and storage period (p>0.05). However, the change in DM and the increase in the relative proportions of lactic acid content and Lactobacillales according to the storage period (p<0.05) indicate that continuous fermentation progressed until OHT days of fermentation. Enterobacterales (33.0%), Flavobacteriales (14.4%), Sphingobacteriales (12.7%), Burkholderiales (9.28%) and Pseudomonadales (6.18%) dominated before fermentation of corn silage, but after fermentation, the diversity of microorganisms decreased sharply due to the dominance of Lactobacillales (69.4%) and Bacillales (11.5%), Eubacteriales (7.59%). Therefore, silage maintained good fermentation quality with or without microbial additives throughout all fermentation periods, but considering the persistence of fermentation even in long-term storage and the aerobic stability, it would be advantageous to use microbial additives.
In recent years, the energy storage sector has experienced a notable transition toward the use of organic electrodes. This shift is largely attributed to their superior energy density, cost-effectiveness, and eco-friendliness. However, there is a main drawback that the organic molecules oftentimes suffer shuttle phenomenon across the separator due to their high solubility in the organic electrolyte. In addition, the low electrical conductivity of organic materials is also detrimental, thereby requiring a large amount of carbon additives (up to 40 wt. %) in the electrode. In this perspective, addition of carbon additives with the desirable amount, which can prevent organic molecules from being dissolved into the liquid phase as well as provide the electrical conductivity. While N,Nʹ-dimethylphenazine (DMPZ) was investigated as a model material, we compared two carbon additives with different surface areas and functional groups. We carefully scrutinized the structural effect of carbon additives on the cycle-life performance of the organic electrode.
본 연구에서는 고투과성 및 높은 염 제거율을 가지는 역삼투막의 성능향상을 위하여 다양한 첨가제 및 계면중합 시 경화 온도 및 시간에 따른 특성평가에 대한 연구가 수행되었다. 첨가제가 없는 막과 첨가제를 첨가한 막의 모폴로지는 모 두 “ridge-and-valley” 구조를 나타내어, 폴리아미드 층이 다공성 지지층 표면에 성공적으로 중합되었음을 확인하였다. 또한 2-Ethyl-1,3-hexanediol (EHD) 첨가함으로써 향상된 친수성과 수투과율 가졌으며, 이는 접촉각 측정을 통해서 확인되었다. 최 종적으로 97.78%와 98.7%의 NaCl 및 MgSO4 제거율과 3.31 L/(m2⋅h⋅bar)의 높은 수투과율을 가진 고투과성 계면중합막을 제조하였다.
PURPOSES : This study was conducted to evaluate the physical properties of the RAP 50 asphalt mixture containing polymer modified rejuvenator and warm-mix additive to improve the recycling rate of RAP and reduce CO2 emission. METHODS : Mix design of Polymer Modified Warm-mix Asphalt Mixture(RAP 50), and Hot Mix Asphalt Mixture(RAP 30) were produced and the properties of asphalt mixture such as Marshall Stability, ITS, Deformation Strength, TSR, and Dynamic Stability were compared between the two asphalt mixtures. RESULTS : The RAP 50 asphalt mixture showed superior or similar performances compared to the RAP 30 asphalt mixture in all the tests conducted. The results of the Marshall stability and dynamic stability in particular were 13,045N and 3,826 pass/mm, which were 11.37% and 76.7% greater than the RAP 30 asphalt mixture, which indicated that high plastic deformation resistance may be expected. CONCLUSIONS : The results obtained from laboratory tests on the two types of mixtures indicated that the use of polymer modified rejuvenator and warm-mix additive not only allows to increase the proportion of RAP but also improves its properties under lower temperature condition than RAP 30 asphalt mixture. Additionally, it was confirmed that plastic deformation resistance was high and moisture resistance and crack resistance were improved for a RAP 50 asphalt mixture.
This study aimed to investigate the effects of amino acid complex additives, such as protected vitamin C (VC) or detoxified sulfur (DS), on the growth and metabolism of Hanwoo cattle under high-temperature conditions. Accordingly, farms in Temperature-Humidity Index (THI) regions ranging from 78 to 89 for over 100 days were selected. The experimental groups were control, T1 (lysine + methionine + VC, 50 g/head/day), and T2 (lysine + methionine + DS, 50 g/head/day) with 70, 77, and 71 animals each. The range of the THI for 115 days was 78-89, and this occurred in most of the experiment days. The results showed that there was no significant difference in rectal temperature among the groups. The body weight increased to 786.4 and 809.0kg in the T1 and T2 groups, respectively, compared to the control group (p<0.05). Linoleic acid showed a high result of 2.01% in the T1 group compared to the control group (p<0.05). Unsaturated fatty acids were higher at 55.70 and 56.54% in the T1 and T2 groups, respectively, compared to the control group (p<0.05), and the omega 6/3 ratio was reduced to 20.10% (p<0.05). These findings indicate that T1 has a positive impact on growth, meat quality, and fatty acid composition compared to the control group. In conclusion, amino acid complex with VC improved the body weight of Hanwoo steers and the unsaturated fatty acids and essential amino acids of their meat; however, further research is needed to clarify this impact on carcass performance.
Asphalt concrete, which is used as a road base material, accounts for >90% of a road pavement. A huge amount of waste concrete and waste asphalt concrete aggregates are generated. Recently, carbon neutrality is promoted across all industries for sustainability. Therefore, to achieve carbon neutrality in the asphalt concrete industry, waste asphalt concrete aggregates should be recycled. Additionally, road base materials are prepared using additives to ensure structural stability, durability, and economic efficiency. In this study, recycled asphalt concrete aggregates were used to evaluate the physical properties of road base materials according to the type of polymer additive and mixing method, and the applicability of road base each material was evaluated. Results showed that when the acrylate-based polymer additive was mixed, the uniaxial compressive strength was 30% higher. Furthermore, the compressive strength of the split mix was improved by ~29% compared to the total mix.
목적 : 최근 전자기기의 발달로 인해 근거리 작업이 증가하고 있으며, 이로 인해 안 건강에 대한 우려가 증가함 에 따라 청광 차단에 대한 관심이 증가하고 있다.
방법 : 유해 광선 차단이 가능한 기능성 콘택트렌즈 소재 개발을 위해 reactive yellow 86을 안료 중합체에, 그리고 propyl gallate를 실리콘 하이드로겔 소재에 첨가제로 각각 사용하여 안 의료용 소프트 콘택트렌즈 제조에 적용하였다.
결과 : propyl gallate의 첨가량에 따라 접촉각이 68.25~42.50˚로 측정되었으며, 습윤성이 향상되는 것으로 나타났다. 또한, 제조된 컬러 소프트 콘택트렌즈는 산소투과성 및 습윤성이 우수함과 동시에 자외선 및 청광 차단 효과를 나타내었다.
결론 : reactive yellow 86 및 propyl gallate가 적용된 컬러 콘택트렌즈의 재료의 경우, 기본적인 안 의료용 하이드로젤 렌즈의 물성을 만족시킴과 동시에 우수한 자외선 및 청광차단 효과를 가지는 것으로 판단된다.