• 한국초지조사료학회지
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• 제42권4호
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• pp.264-269
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• 2022

본 연구에서는 미생물 첨가에 따라 거세한우 비육우 분의 이화학적 특성, 미생물 성상, 가스발생량 및 퇴비 부숙도에 미치는 영향을 규명하고자 수행하였다. 이상의 결과를 종합하면, 4주 후, 미생물 첨가구에서 수분, 유기물, 총질소 함량 및 pH가 낮았으며, 나머지 이화학적 특성에서는 차이가 나타나지 않았다. 유산균과 효모균 수는 증가하였으며, 대장균 수는 감소하였다. 12주 후, 미생물 첨가구에서 유산균과 고초균 수는 높았으나, 수분, 효모 및 대장균 수는 낮게 낮았다. 하지만 암모니아, 황화수소 발생량과 퇴비 부숙도는 미생물 첨가에 의한 효과가 나타나지 않았다. 따라서, 거세한우 분에 미생물을 첨가하면 유익균은 증가하고, 병원성 미생물은 감소하여, 비육우의 생산성은 증진될 것으로 사료되지만, 가스 발생량 및 퇴비 부숙도에 대한 추가적인 연구는 지속적으로 수행되어야 할 것으로 사료된다.

• 한국산학기술학회논문지
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• 제11권10호
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• pp.4069-4074
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• 2010

침전탄산칼슘 결정화계에서 첨가제인 ethylenediaminetetraacetic acid(EDTA), diethylene triaminepentaacetic acid(DTPA), citric acid(CIT), pyromellitic amid(PMA) 첨가에 의한 탄산칼슘 결정의 형상 변화를 연구하였다. 첨가제를 넣지 않았을 때 낮은 온도 $20^{\circ}C$에서는 calcite 결정이 생성되었고, 높은 온도 $80^{\circ}C$에서는 aragonite 결정이 생성되었으며 EDTA 와 DTPA 첨가에 의한 $40^{\circ}C$, $60^{\circ}C$ 중간온도에서는 aragonite 결정이 생성됨을 알 수 있었다. CIT와 PMA 첨가에 의해 aragonite의 성장이 지연 되었으며 calcite 단일상이 나타났다. 첨가제가 단일상의 탄산칼슘을 만드는데 중요한 요소임을 발견되었다.

• 대한환경공학회지
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• 제32권6호
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• pp.625-630
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• 2010

본 연구는 발전소등에서 발생하는 중유회를 재활용한 탈취패널 제조시 활성탄, 규조토등의 첨가제를 활용함으로써 포름알데히드 및 톨루엔에 대한 제거성능을 향상시켜 중유회의 탈취패널 원료로서의 사용가능성을 확인하였다. 단일 첨가제를 사용하여 제작된 중유회 재활용 탈취패널의 경우 포름알데히드에 대해서는 93% 이상, 톨루엔에 대해서는 97% 이상의 제거성능을 보였으나 기준 패널에 비하여 압축강도가 27~63% 감소하였다. 반면에 두 가지 첨가제를 여러 가지 비율로 혼합하여 제조된 것 중 활성탄과 규조토가 5 wt%씩 첨가된 패널은 포름알데히드 84%, 톨루엔 96%의 제거성능을 보였으며 압축강도는 기준패널보다 32%증가하였다. 따라서 첨가제의 혼합사용을 통하여 중유회재활용 탈취패널을 제조할 경우 유해가스 제거성능과 패널의 강도를 향상 시키는 것이 확인되었다.

• Tribology and Lubricants
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• 제4권1호
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• pp.43-55
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• 1988

A Study on the effect of the additives in lubricating oil was investigated on the basis of the thermal activated wear theory in terms of their wear behaviours, using four ballwear machine. The sample oils, which included diethyl-3, 5-di-t-butyi-4-hydroxy-benzyl phosphonate (DEP), ZDDP and TCP additives respectively, showed distinct wear characteristics depending upon the bulk oil temperature and the sliding velocity. The newly synthesized additive, viz., DEP showed excellent antiwear performance cornpared with the conventional additives, ZDDP and TCP. On the basis of the experimental results, it is reduced that the wear mechanism of the conventional additives, viz., ZDDP and TCP is the protective film formation and their antiwear capability is depending upon the shearing strength of the film formed. On the other hand, the new additive, DEP showed that the secondary activation energy was much eliminated and so, the thermal instability was reduced by the hydrogen scavenging reaction of the new additive, which was virtually an endothermic reaction process.In conclusion, a new concept of antiwear mechanism is estabilished and testified. And new chemical, which showed the function of hydrogen and free radical scavenging role, is synthesized and introduced as the new, highly antiwear effective lubricating oil additive.

• 한국임상약학회지
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• 제23권2호
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• pp.97-105
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• 2013

Background: This study was aimed to establish the systematic management methods of tar color additives used in Korea for drugs and quasi-drugs. Although tar color additives have been used in various areas, safety problems are continuously being reported by several studies. For that reason, major countries like US, Japan, Europe are trying to update the safety information of tar color additives and the related management methods, and Korea also need to complement them based on the updated information for their safer use. Method: This report includes the compared information of all legally used tar color additives of each country, such as color additive name, compound name and chemical abstracts service registry number. Conclusion: It is expected that these investigated results will be useful as the basic materials for proper management guidelines of tar color additives in Korea.

• Bulletin of the Korean Chemical Society
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• 제33권5호
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• pp.1603-1607
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• 2012

The effects of plating process on the surface coverage of the accelerator were investigated in terms of Cu superfilling for device metallization. When a substrate having 500 nm-wide trench patterns on it was immersed in an electrolyte containing poly (ethylene glycol) (PEG)-chloride ion ($Cl^-$)-bis(3-sulfopropyl) disulfide (SPS) additives without applying deposition potential for such a time of about 100s, voids were generated inside of the electrodeposit. In time-evolved electrochemical analyses, it was observed that the process (immersion without applying potential) in the electrolyte led to the build-up of high initial coverage of SPS-Cl on the surface, resulting in the fast saturation of the coverage. Repeated experiments suggested that the fast saturation of SPS-Cl failed in superfilling while a gradual increase in the SPS-Cl coverage through competition with initially adsorbed PEG-Cl enabled it. Consequently, superfilling was achievable only in the case of applying the plating potential as soon as the substrate is dipped in an electrolyte to prevent rapid accumulation of SPS-Cl on the surface.

• 펄프종이기술
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• 제43권4호
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• pp.40-48
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• 2011

In this study, we investigated the usability of new powdered additives in the paperboard industry. We manufactured the powdered additives from peanut husks and garlic stems by grinding. The chemical composition, particle size, particle size distribution, and particle shape were investigated to identify the basic properties of the powdered raw materials. To determine the effect of the powdered additives on paper properties, handsheets were prepared by adding the powdered additives to the pulp slurry. The chemical composition, such as the contents of holocellulose, lignin, and ash, showed similar values to those of other biomass materials. The particles of peanut husk powder were irregularly shaped, smaller, and had a broader particle size distribution than those of the garlic stem powder, which had the fibril form. The particles of the two powdered raw materials showed a positioning of expansion in the fiber network, resulting in increased bulk and a loss of strength. Handsheets containing garlic stem particles were stronger than handsheets containing peanut husk particles. Finally, the new powdered additives are beneficial to the bulk of paperboard.

• 공업화학
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• 제18권6호
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• pp.531-536
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• 2007

본 총설은 최근 제지 분야에 적용되어 종이의 품질을 향상시키고 생산효율을 개선하는 등 제지산업의 경제성 향상을 이끌어 내거나 장차 이끌어낼 것으로 기대되는 새로운 제지용 첨가제를 소개하기 위하여 작성되었다. 본 총설에서는 최근 개발되어 제지 현장에 적용된 새로운 첨가제에 대한 소개뿐만 아니라 그 적용 원리, 방법, 조절 및 점검 방안과 향후 발전 방향에 대하여 논의하였다. 기본적으로 2000년대에 들어선 지난 수년 동안 제지산업의 기술개발 노력은 기 개발된 기술의 최적화를 통한 경제성 확보 및 종이 품질과 생산 효율의 개선에 집중되어 왔다. 따라서 제지용 첨가제 분야에 혁신적인 변화는 없었다고 볼 수 있으나 기술적인 측면에서 몇 가지 중요한 첨가제의 개발이 보고되었으며 이를 바탕으로 기존의 제지공정에 대한 보다 합리적인 관리가 가능하게 되었다고 할 수 있다.

• 한국응용과학기술학회지
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• 제33권4호
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• pp.734-740
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• 2016

The micron-sized indium zinc tin oxide (IZTO) particles were prepared by spray pyrolysis from aqueous precursor solution for indium, zinc, and tin and organic additives such as citric acid (CA) and ethylene glycol (EG) were added to aqueous precursor solution for indium, zinc, and tin. The obtained IZTO particles prepared by spray pyrolysis from the aqueous solution without organic additives had spherical and filled morphologies, whereas the IZTO particles obtained with organic additives had more hollow and porous morphologies. The micron-sized IZTO particles with organic additives were changed fully to nano-sized IZTO particles, whereas the micron-sized IZTO particles without organic additives were not changed fully to nano-sized IZTO particle after post-treatment at $700^{\circ}C$ for 2 hours and wet-ball milling for 24 hours. Surface resistances of micron-sized IZTO's before post-heat treatment and wet-ball milling were much higher than those of nano-sized IZTO's after post-heat treatment and wet-ball milling. From IZTO with composition of 80 wt. % $In_2O_3$, 10 wt. % ZnO, and 10 wt. % $SnO_2$ which showed a smallest surface resistance IZTO after post-heat treatment and wet-ball milling, thin films were deposited on glass substrates by pulsed DC magnetron sputtering, and the electrical and optical properties were investigated.

• Carbon letters
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• 제15권3호
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• pp.187-191
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• 2014

This study reports on the influence of N-butyl-N-methylpyrrolidinium tetrafluoroborate ($PYR_{14}BF_4$) ionic liquid additive on the conducting and interfacial properties of organic solvent based electrolytes against a carbon electrode. We used the mixture of ethylene carbonate/dimethoxyethane (1:1) as an organic solvent electrolyte and tetraethylammonium tetrafluoroborate ($TEABF_4$) as a common salt. Using the $PYR_{14}BF$ ionic liquid as additive produced higher ionic conductivity in the electrolyte and lower interface resistance between carbon and electrolyte, resulting in improved capacitance. The chemical and electrochemical stability of the electrolyte was measured by ionic conductivity meter and linear sweep voltammetry. The electrochemical analysis between electrolyte and carbon electrode was examined by cyclic voltammetry and electrochemical impedance spectroscopy.