• Proceedings of the Korean Institute of Building Construction Conference
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• 2023.11a
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• pp.115-116
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• 2023

In this study, it was confirmed whether kaolin can play a role as a bed materials and a role in reducing clinkers by using kaolin with a bed materials for the purpose of removing clinkers such as slagging and fouling generated in circulating fluidized bed combustion furnaces using solid fuel.

• Journal of the Microelectronics and Packaging Society
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• v.15 no.1
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• pp.45-50
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• 2008

The effects of electrolytes and additives on the electropolishing of 50 and $20{\mu}m$ diameter copper via were investigated to flatten 3D SiP through via. The termination time was determined with analysis of applied potential on anode and cathode to avoid excess electropolishing. Acetic acid played a role of accelerator and glycerol played a role of inhibitor in phosphoric acid electrolytes. The overplated copper on the through via was effectively electropolished in the phosphoric electrolytes with acetic acid and glycerol addition. The electropolishing was terminated at the point of abrupt change of applied potential to remove only overplated copper on the through via.

• Advances in concrete construction
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• v.11 no.2
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• pp.163-171
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• 2021

This paper studies the effect of using multi-scale reinforcement additives on mechanical strengths, damage performance, microstructure, and water absorption of cementitious composites. Small dosages of carbon nanotubes (CNTs) or polypropylene (PP) microfibers; 0.05%, 0.1%, and 0.2% by weight of cement; were added either separately or simultaneously into cement mortar. The experimental results show the ability of these additives to enhance the mechanical behavior of the mortar. The best improvement in compressive and flexural strengths of cement mortar reaches 28% in the case of adding a combination of 0.1% CNTs and 0.2% PP fibers for compression, and a combination of 0.2% CNTs and 0.2% PP fibers for flexure. Adding CNTs does not change the brittle mode of failure of plain mortar whereas the presence of PP fibers changes it into ductile failure and clearly enhances the fracture energy of the specimens. Scanning electron microscopic (SEM) images of the fracture surfaces highlights the role of CNTs in improving the adhesion between the PP fibers and the hydration products and thus enhance the ability of the fibers to mitigate cracks propagation and to enhance the mechanical performance of the mortar.

• Tribology and Lubricants
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• v.40 no.3
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• pp.78-83
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• 2024

The development of eco-friendly alternative energy sources has become a global priority owing to the depletion of fossil fuels and an increase in environmental concerns. Hydrogen energy has emerged as a promising clean energy source, and hydrogen compressors play a crucial role in the storage and distribution of compressed hydrogen. However, harsh operating conditions lead to the rapid deterioration of conventional lubricants in hydrogen compressors, thereby necessitating the development of advanced lubrication technologies. This study introduces micrometer-sized silicone rubber powders as lubricant additives to enhance the lubrication performance of hydraulic oils in hydrogen compressors. We prepare silicone rubber powders by varying the ratio of the silicone rubber base to the curing agent and investigate their effects on interfacial properties, friction behavior, and wear characteristics. The findings reveal that the incorporation of silicone rubber powders positively influences the surface affinity, wettability, friction reduction, and wear resistance of the lubricants on the 304SS substrate. Moreover, we identify the optimal lubricant formulations, with a 15:1 ratio demonstrating the most effective friction reduction and a 5:1 ratio exhibiting the highest wear resistance. The controlled surface modification by the silicone rubber powder and the enhanced interfacial characteristics of the powder-containing lubricants synergistically contribute to the improved lubrication performance. These results indicate the potential of silicone rubber powder additives for the development of long-life lubrication solutions for hydrogen compressors and related applications, ultimately contributing to the advancement of sustainable energy technologies.

• Archives of Pharmacal Research
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• v.7 no.1
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• pp.1-9
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• 1984

Polyethylene glycol 20, 000 and 6, 000 were found to have an upper consolute temperature, called "cloud point", and the effects of various additives on the polythylene glycols were investigated in this study. Electrolytes lowered the cloud point in proportion to their concentrations through dehydration and electrostriction. It was found that anions played a more important role than cations and the effects of both the cations and the anions clearly followed the classical Hofmeister series. However, the Schultze Hardy rule holds for the effect of anions, and fails for the effect of cations. Salts of large polarizable anions such as iodide and thiocynate rather raised the cloud point, and their effects were ascribed to the fact that they break the water structure and weaken hydrophobic bonding of the polyxyethylene moiety. Nitrates of polyvalent cations also raised the cloud point. This was ascribed to the complex formation between the polyvalent cations and ether oxygens of the polyoxyethylenes. This explained the failure 'of the Schultz-Hardy rule for cations. Uncharged aromatic compounds drastically lowered the clound point, while aliphatic alcohols slightly lowered the cloud point, This result suggests that there might be some interaction between ether oxygens and aromatic nucleus.c nucleus.

• Journal of Hydrogen and New Energy
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• v.19 no.3
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• pp.189-198
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• 2008

Cooperative effects of Rh, Ce and Zr added to Fe-based oxide mediums were investigated using temperature programmed redox reaction (TPR/TPO) and isothermal redox reaction in the view point of hydrogen storage and release. As the results of TPR/TPO, Rh was a sale additive to remarkably promote the redox reaction on the medium as evidenced by the lower highest peak temperature, even though its addition was to accelerate deactivation of the mediums due to sintering. On the other hand, Ce and Zr additives played an important role to suppress deactivation of the medium in repeated redox cycles. The medium co-added by Rh, Ce and Zr (FRCZ) exhibited synergistic performance in the repeated isothermal redox reaction, and the amount of hydrogen produced in the water splitting step at 623 K was highly maintained at ca. $17\;mmol{\cdot}g^{-1}-Fe$ during three repeated redox cycles.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.24 no.2
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• pp.156-161
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• 2011

The present study introduces a novel wet etching technique for nanostructure fabrications which usually requires low surface roughness. Using the current method, acquired profiles were smooth even in the nanoscale, which cannot be easily achieved with conventional wet or dry etching methods. As one of the most popular single crystal silicon etchant, potassium hydroxide (KOH) solution was used as a base solvent and two additives, antimony trioxide (Sb2O3) and ethyl alcohol were employed in. Four experimental parameters, concentrations of KOH, Sb2O3, and ethyl alcohol and temperature were optimized at 60 wt.%, 0.003 wt.%, 10 v/v%, and $23^{\circ}C$, respectively. Effects of additives in KOH solution were investigated on the profiles in both (110) and (111) planes of single crystal silicon wafer. The preliminary results show that additives play a critical role to decrease etch rate significantly down to ~2 nm/min resulting in smooth side wall profiles on (111) plane and enhanced surface roughness.

• Journal of Environmental Science International
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• v.32 no.10
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• pp.741-744
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• 2023

This study focused on high school laboratory research and the main purpose was to develop alternative additives for livestock waste and ammonia volatilization methods with high school students as participants and to provide information to business owners based on the results. Compared to the control groups, The bentonite and illite treatment groups had similar ammonia volatilization, pH, EC, and total nitrogen content. In particular, the alum and aluminum chloride mixed treatment group showed low pH and ammonia volatilization, and high EC and total nitrogen content for poultry litter. As a result, when focusing on high school laboratory research, the alum and aluminum chloride mixed agent treatment fulfilled its role as an alternative additive for ammonia reduction. In addition, this approach can be suggested as a method to solve difficulties in adapting to the field through a practical cooperative relationship with livestock farms.

• Journal of Environmental Science International
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• v.11 no.3
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• pp.235-240
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• 2002

The blocks using flyash were prepared in this study. The characteristic of sound absorption of flyash block was investigated. It was revealed that the chemical additives and flyash played an important role to determine the characteristic of sound absorption. Chemical additive affects the capability of sound absorption while flyash affects the characteristic of sound absorption, i.e. high value of the sound absorption coefficient at the specific frequencies(1KHz and 2KHz). The flyash block showed higher sound absorption coefficient than that of the commercial concrete block having carpet on the surface. It was also shown that the sound absorption coefficient increases with increase of the content of flyash in the block. However, it was found that the 70wt% of flyash in the flyash block was the optimum content to obtain the highest sound absorption coefficient.

• Korean Journal of Poultry Science
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• v.39 no.1
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• pp.53-62
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• 2012

In the past, poultry nutrition has focussed on increasing the production efficiency to meet the progress achieved in the genetic potential of broilers and layers. Future directions in poultry nutrition will be driven by not only by the need to maximise biological and economic performance of birds, but also by societal issues (environment, antibiotic growth promoters, welfare, traceability and use of genetically modified ingredients). Key advances in poultry nutrition are discussed and future directions, which can be expected, are highlighted. Given the tightening supply and ever-increasing cost of raw materials, there will be more pressure to extract every unit of energy and nutrients from feed ingredients. In this context, a number of feed additives are expected to play an increasingly significant role. Feed enzymes and crystalline amino acids, in particular, will have a profound effect on future sustainability of the poultry industry. Future nutritional research need to focus on identifying the barriers to effective digestion and utilisation of nutrients and, to achieve this objective, nutritionists must combine their expertise with those of specialising in other biological sciences, including immunology, microbiology, histology and molecular biology.