• 한국재료학회:학술대회논문집
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• 한국재료학회 2006년도 춘계학술발표대회 및 제10회 신소재 심포지엄 논문개요집
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• pp.17.1-17.1
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• 2006

• 펄프종이기술
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• 제48권1호
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• pp.111-118
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• 2016

The effects of pulp beating degree and bulky promotor concentration on the properties of handsheet including a bulk and strength have been investigated during manufacturing of low density paper (high bulk paper) with cationic fatty acid bulky promotor. It was found that paper bulk increased with increasing cationic fatty acid bulky agent concentration, while tensile strength decreased. On the other hand the opacity of handseets also increased with increasing cationic fatty acid bulky agent concentration, while brightness decreased slightly. With increasing pulp beating degree, paper bulk as well as tensile strength increased, while opacity decreased. Brightness did not show a significant difference with increasing pulp beating degree. The highest bulk and strength values were observed when 1.5% (SwBKP) and 2% (HwBKP) of bulky promotor was treated into the 450 mL CSF pulp slurry.

• 한국축산시설환경학회지
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• 제14권2호
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• pp.91-96
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• 2008

The odours from spreading the slurry, manure storage tanks, and the stall are a source of annoyance for the neighbors and sometimes even become a case for civil appeal. Reducing the odourant and ammonia emission is an urgent need to be addressed. It is known that brown coal and oak charcoal have an ability to absorb odour. We designed an experiment set in lab scale and used the brown coal and oak charcoal as additives in the test to reduce odour. The test are divided into two categories; namely aeration and no-aeration. The additives were added to the each sample at a concentration of 5% and 10% of total base solids, besides the control samples. We carried out the Phenate Method for ammonia analyzing. In the non-aerated case, the results showed a reducing efficiency of 23.7% and 26.4% with an addition rate of 5% and 10% of additives, respectively. In the aerated test, the reducing efficiency of ammonia was 17.8% and 21.0% with an addition rate of 5% and 10% of additives, respectively. In case of oak charcoal, non-aeration showed removal efficiencies of ammonia at 15.9% and 16.1% with addition rates of 5% and 10%, respectively, With aeration, they were 11.4% and 26.4% with addition rates of 5% and 10% oak charcoal, respectively. The tests show that brown coal and oak charcoal have a reducing effect on ammonia emissions.

• 한국축산시설환경학회지
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• 제8권1호
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• pp.17-24
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• 2002

본 연구는 돈분 완숙퇴비에서 돼지분뇨 악취제어 효과가 뛰어난 효모를 분리하고, 그들의 특성을 조사하여 악취미생물에 관한 기초자료를 얻고자 수행하였다. 10% 돈분배지에서 성장이 우수한 균주를 선발하고 10% 돈분액체배지에 접종하여 28$^{\circ}C$ 72시간 배양한 후 가스경지간을 이용하여 암모니아와 아민류를 측정하여 이들에 대한 기질 선호성을 가진 호모를 악취유용 미생물로 CY-10을 선발하였다. 이의 형태적, 생화학적 특성에 따라 희비에서 분리한 CY-10은 Candida rugosa로 동정되어 본 시험에 공시로 Candida rugosa CY-10으로 하였다. 이의 악취저감능을 조사하기 위해서 돈분 액체배지에 성장시키면서 이들 배양액의 휘발성 지방산을 분석한 결과 대조구에 비해 CY-10의 경우 iso- butric acid와 busic acid를 100% 감소시켜 뷰틸산류에 기질특이성이 있는 것으로 나타났으며 또한 이의 처리구는 대조구에 비해 $NH_4$-N, Soluble-N, BOD즐 각각 20%, 12.6%, 9.82%를 감소시키는 효과가 있었다

• 한국세라믹학회지
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• 제51권3호
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• pp.145-149
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• 2014

A hydroxyapatite microsphere was prepared using a spray-drying method. The change in the shape as a function of the slurry concentration and the change in the degree of shrinkage according to the heat-treatment temperatures were observed. To obtain biomaterials with improved bio-stability, $CaHPO_4{\cdot}2H_2O$ and $Ca(OH)_2$ were mixed at a ratio of 6 : 4 and then ball-milled to synthesize hydroxyapatite. The hydroxyapatite microsphere was prepared using 30 wt% ~ 80 wt% hydroxyapatite slurry by a spray-drying method. For concentrations lower than 50 wt% or higher than 80 wt%, doughnut-shaped microspheres were produced. However, perfect microspheres were produced when using slurry concentrations of 50 wt% ~ 70 wt%. A dense microstructure was observed after a heat treatment at temperatures higher than $1100^{\circ}C$ and the size was reduced by 24.3% at these temperatures.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2005년도 추계학술대회 논문집 Vol.18
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• pp.68-69
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• 2005

BTO ($BaTiO_3$) thin film is one of the high dielectric materials for high-density dynamic random access memories (DRAMs) due to its relatively high dielectric constant. It is generally known that BTO film is difficult to be etched by plasma etching, but high etch rate with good selectivity to pattern mask was required. The problem of sidewall angle also still remained to be solved in plasma etching of BTO thin film. In this study, we first examined the patterning possibility of BTO film by chemical mechanical polishing (CMP) process instead of plasma etching. The sputtered BTO film on TEOS film as a stopper layer was polished by CMP process with the self-developed $BaTiO_3$- and $TiO_2$-mixed abrasives slurries (MAS), respectively. The removal rate of BTO thin film using the$ BaTiO_3$-mixed abrasive slurry ($BaTiO_3$-MAS) was higher than that using the $TiO_2$-mixed abrasive slurry ($TiO_2$-MAS) in the same concentrations. The maximum removal rate of BTO thin film was 848 nm/min with an addition of $BaTiO_3$ abrasive at the concentration of 3 wt%. The sufficient within-wafer non-uniformity (WIWNU%)below 5% was obtained in each abrasive at all concentrations. The surface morphology of polished BTO thin film was investigated by atomic force microscopy (AFM).

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2006년도 영호남 합동 학술대회 및 춘계학술대회 논문집 센서 박막 기술교육
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• pp.101-102
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• 2006

BTO ($BaTiO_3$) thin film is one of the high dielectric materials for high-density dynamic random access memories (DRAMs) due to its relatively high dielectric constant, It is generally known that BTO film is difficult to be etched by plasma etching, but high etch rate with good selectivity to pattern mask was required. The problem of sidewall angle also still remained to be solved in plasma etching of BTO thin film. In this study, we first examined the patterning possibility of BTO film by chemical mechanical polishing (CMP) process instead of plasma etching. The sputtered BTO film on TEOS film as a stopper layer was polished by CMP process with the sell-developed $BaTiO_3$- and $TiO_2$-mixed abrasives slurries (MAS). respectively. The removal rate of BTO thin film using the $BaTiO_3$-mixed abrasive slurry ($BaTiO_3$-MAS) was higher than that using the $TiO_2$-mixed abrasive slurry ($TiO_2$-MAS) in the same concentrations. The maximum removal rate of BTO thin film was 848 nm/min with an addition of $BaTiO_3$ abrasive at the concentration of 3 wt%.

• Environmental Engineering Research
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• 제10권3호
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• pp.138-143
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• 2005

Laboratory batch experiments were conducted to evaluate the Fenton degradation rates of phenanthrene. Fenton reactions for the degradation of phenanthrene were carried out with aqueous and slurry phase, to investigate the effects of sorption of phenanthrene onto solid phase. Various types of surfactants and electrolyte solutions were used to evaluate the effects on the phenanthrene degradation rates by Fenton's reaction. A maximum 90% removal of phenanthrene was achieved in aqueous phase with 0.9% of $H_2O_2$ and 300 mg/L of $Fe^{2+}$ at pH 3. In aqueous phase reaction, inhibitory effects of synthetic surfactants on the removal of phenanthrene were observed, implying that surfactant molecules acted as strong scavenger of hydroxyl radicals. However, use of $carboxymethyl-{\beta}-cyclodextrin$ (CMCD), natural surfactant, showed a slight enhancement in the degradation of phenanthrene. It was considered that reactive radicals formed at ternary complex were located in close proximity to phenanthrene partitioned into CMCD cavities. It was also show that Fenton degradation of phenanthrene were greatly enhanced by addition of NaCl, indicating that potent radical ion ($OCI^-$) played an important role in the phenanthrene degradation, although chloride ion might be acted as scavenger of radicals at low concentrations. Phenanthrene in slurry phase was resistant to Fenton degradation. It might be due to the fact that free radicals were mostly reacting with dissolved species rather than with sorbed phenanthrene. Even though synthetic surfactants were added to increase the phenanthrene concentration in dissolved phase, low degradation efficiency was obtained because of the scavenging of radicals by surfactants molecules. However, use of CMCD in slurry phase, showed a slight enhancement in the phenanthrene degradation. As an alternative, use of Fenton reaction with CMCD could be considered to increase the degradation rates of phenanthrene desorbed from solid phase.

• 한국건축시공학회지
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• 제12권1호
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• pp.22-30
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• 2012

Four types of foaming agents, including Alcohol Ethoxy Sulfate (AES), Alpha Olefin Sulfonate (AOS), Vegetable Soap (VS), and Fe-Protein (FP), are widely used in the construction field. These have different surface tensions and viscosities in water of the same concentration, affecting the flow speed of liquid, size and distribution of foam, and foam stability. However, there is a lack of data regarding the properties of foam concrete using various foam agents. The purpose of this study is to investigate influence of foaming agents on the properties of foamed concretes with various densities. We find that the foaming agent type has little effect on the density, compressive strength, and thermal conductivity of foam concrete, but considerably affects the unit weight of foam, flow and flexural strength of foamed concrete. While almost all properties of foam concrete are affected by density in fresh or hardened state, the potential energy changed by slurry density and the viscosity of foam are dominant factors in the flowability of foam slurry.

• 한국초전도ㆍ저온공학회논문지
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• 제19권1호
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• pp.17-21
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• 2017

Vanadium slags is a kind of vanadiferous solid waste from steelmaking process. It not only occupies land, pollutes environment, but also leads to waste of resources. Based on the difference of magnetic susceptibility of different particles caused by their chemical and physical properties from vanadium slag, a new technology, superconducting high gradient magnetic separation was investigated for separation and extraction of valuable substances from vanadium slag. The magnetic concentrate was obtained under optimal parameters, i.e., a particle size -200 mesh, a magnetic flux density of 0.8 T, a slurry concentration of 5 g/L, an amount of steel wools of 25 g and a slurry flow velocity of 2 L/min. The content of $Fe_2O_3$ in concentrate could be increased from 39.6% to 55.0% and $V_2O_5$ from 2.5% to 4.0%, respectively. The recovery rate is up to 42.9%, and the vanadium slag has been effectively reused.