• 자원리싸이클링
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• 제28권5호
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• pp.42-50
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• 2019

본 연구에서는 바나듐을 회수하기 위하여 수용액의 바나듐과 염화암모늄 침전반응에 관하여 고찰하였다. 바나듐 함유 수용액 pH 9.2 ~9.4에서는 결정구조가 [$NH_4VO_3$]인 암모늄메타바나데이트가 침전되었고, 바나듐 함유 수용액의 pH를 황산으로 조절하면 결정구조가 [$(NH_4)_2V_6O_{16}$]인 암모늄폴리바나데이트가 침전되었다. 암모늄폴리바나데이트[$(NH_4)_2V_6O_{16}$]는 바나듐 함유 수용액 pH 2에서는 침전온도 $80{\sim}90^{\circ}C$에서, 그리고 수용액 pH 6 ~ 8에서는 침전온도 $40^{\circ}C$에서 침전되었다. 또한 수용액 pH 2인 산성 영역에서 99% 이상의 침전률을 얻기 위해서는 수용액의 바나듐 함량이 3,000 mg/L 이상은 되어야 하며, 침전온도는 $80^{\circ}C$ 이상으로 유지해야 한다. 알칼리 영역에서 암모늄메타바나데이트를 침전시킬 때, 바나듐 함량은 10,000 mg/L 이상 그리고 침전온도는 $40^{\circ}C$로 유지해야 침전률을 높일 수 있었다. 알루미늄은 수용액의 바나듐 함량 및 pH에 상관없이 거의 침전이 일어나지 않았으나, 철 성분은 염화암모늄과 반응하여 암모늄 자로사이트 형태로 침전되며, 따라서 바나듐의 회수율을 높이기 위해서는 Fe 성분을 우선적으로 제거해야만 한다.

• 환경위생공학
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• 제13권1호
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• pp.57-68
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• 1998

This study was surveyed to examine the removable ability of residual aluminum with the coagulants(LAS, PAC) and the auxiliary coagulants(Loess, R-calmont) on raw water. The leaching test of the auxiliary coagulant showed that the loess contained a lot of Al, Fe and Mn. On the reverse, the R-calmont was a little. Most of the loess were composed of $SiO_{2}$ 53.25%, $Al_{2}O_{3}$ 29.28%, $Fe_{2}O_{3}$ 10.73% and Si/Al ratio was 3.08. In using both LAS vs. loess and PAC vs. loess as the coagulated material, the removal of residual aluminum was the highest as 96.3%, 96.6% respectively, and that of the residual turbidity was 95.0% when PAC vs. R-calmont was dosed 0.2mg/L. Also, loess showed better than R-calmont in the removable efficiency of aluminum and turbidity. When the setting time of auxiliary coagulant was input ar the same time with coagulant, the removal aluminum was the highest as 93.3% to 96.6%.

• 자원환경지질
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• 제41권3호
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• pp.299-314
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• 2008

북동 방향의 호남전단대는 한국의 옥천대 남쪽 경계와 선캠브리아기 영남육괴 사이를 지나는 광역적인 우수향 주향 이동 단층대로 동아시아의 두드러진 지나 변형의 방향과 평행하다. 이 논문에서는 호남전단대의 한 지류인 예천전단대 명호지역의 선캠브리아기 압쇄 석영-백운모 편마암과 엽리상 각섬석-흑운모 화강암의 지화학 및 Nd-Sr 동위원소자료를 보고하고자 한다. 엽리상 각섬석-흑운모 화강암류를 $SiO_2$ 대 $Na_2O+K_2O$의 분별도에 도시하면 $SiO_2$의 함량은 61.9-67.lwt% 그리고 $Na_2O+K_2O$의 함량은 5.21-6.99wt%로 화강섬록암 영역에 대부분이 점시된다. 선캠브리아기 압쇄 석영-백운모 편마암은 화강암의 영역에 점시된다. $SiO_2$에 대한 수정된 알칼리-라임 지수 및 Fe#($FeO_{total}/(FeO_{total}+MgO)$)에 의한 관계도에서 엽리상 각섬석-흑운모 화강암류는 캘크-알카리 계열의 마크네슘 성분이 우세한 코딜러리안(Cordilleran)형 중생대 화강암류의 지화학 특징과 잘 부합된다. 또한 이들 암석들은 $Al_2O_3/(CaO+Na_2O+K_2O)$가 $0.89{\sim}1.10$로 중알루미나에서 약한 고알루미나질의 I형에 해당한다 하지만, 원남층의 압쇄 편마암은 $1.11{\sim}1.22$의 과알루미나질을 보여준다. 연구지역 엽리상 각섬석-흑운모 화강암류 및 압쇄 편마암류의 미량원소 성분을 초생맨틀(Primitive mantle) 값으로 규격화한 거미 성분도상에서는 저장력 원소(large ion lithophile element)이며 불호정성 원소인 Rb, Ba, Th 및 U이 부화되어 있고 Ta, Nb, P, Ti 가 상대적으로 다른 원소보다 결핍되어 있으며 이러한 지화학적 특징은 호상형(Arc-type) 화강암류와 전형적인 활동성 대륙연변부의 지각물질로부터 유래한 화강암류와 유사하다. ${\varepsilon}_{Nd}(T)$와 Sr 초생값은 엽리상 각섬석-흑운모 화강암류가 상부지각의 기원물질로부터 형성된 마그마로부터 생성되었음을 지시해 주고 있다. 연구지역을 포함한 영주저반의 엽리상 각섬석-흑운모 화강암류는 전단대에서 멀어지면서 변형에 의한 특정 원소들(Ti, P, Zr, V 및 Y)의 변화경향이 관찰되지 않는다. 이러한 원인으로, 많은 유체를 가지고 있는 엽리상 각섬석-흑운모 화강암류에서는 전단운동 변형동안 전단대 내와 외부의 유체의 흐름에 의한 질량 전달이 동일하게 일어나 암석 내의 부피변화 및 지화학 변질들을 야기 시키지 않았을 것으로 추정된다.

• Environmental Engineering Research
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• 제23권2호
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• pp.181-188
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• 2018

Photocatalytic oxidation in the presence of Fe-doped, Zn-doped or Fe-Zn co-doped $TiO_2$ was used to effectively decompose humic acids (HAs) in water. The highest HAs removal efficiency (65.7%) was achieved in the presence of $500^{\circ}C$ calcined 0.0010% Fe-Zn co-doped $TiO_2$ with the Fe:Zn ratio of 3:2. The initial solution pH value, inorganic cations and anions also affected the catalyst photocatalytic ability. The HAs removal for the initial pH of 2 was the highest, and for the pH of 6 was the lowest. The photocatalytic oxidation of HAs was enhanced with the increase of the $Ca^{2+}$ or $Mg^{2+}$ concentration, and reduced when concentrations of some anions increased. The inhibition order of the anions on $TiO_2$ photocatalytic activities was $CO{_3}^{2-}$ > $HCO_3{^-}$ > $Cl^-$, but a slightly promotion was achieved when $SO{_4}^{2-}$ was added. Total organic carbon (TOC) removal was used to evaluate the actual HAs mineralization degree caused by the $500^{\circ}C$ calcined 0.0010% Fe-Zn (3:2) co-doped $TiO_2$. For tap water added with HAs, the $UV_{254}$ and TOC removal rates were 57.2% and 49.9%, respectively. The $UV_{254}$ removal efficiency was higher than that of TOC because of the generation of intermediates that could significantly reduce the $UV_{254}$, but not the TOC.

• Nuclear Engineering and Technology
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• 제40권6호
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• pp.497-504
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• 2008

In a study of the optimum operational condition for a melting decontamination, the effects of the basicity, slag type and slag composition on the distribution of depleted uranium were investigated for radioactively contaminated metallic wastes of iron-based metals such as stainless steel (SUS 304L) in a direct current graphite arc furnace. Most of the depleted uranium was easily moved into the slag from the radioactive metal waste. The partitioning ratio of the depleted uranium was influenced by the amount of added slag former and the slag basicity. The composition of the slag former used to capture contaminants such as depleted uranium during the melt decontamination process generally consists of silica ($SiO_2$), calcium oxide (CaO) and aluminum oxide ($Al_2O_3$). Furthermore, calcium fluoride ($CaF_2$), magnesium oxide (MgO), and ferric oxide ($Fe_2O_3$) were added to increase the slag fluidity and oxidative potential. The partitioning ratio of the depleted uranium was increased as the amount of slag former was increased. Up to 97% of the depleted uranium was captured between the ingot phase and the slag phase. The partitioning ratio of the uranium was considerably dependent on the basicity and composition of the slag. The optimum condition for the removal of the depleted uranium was a basicity level of about 1.5. The partitioning ratio of uranium was high, exceeding $5.5{\times}10^3$. The slag formers containing calcium fluoride ($CaF_2$) and a high amount of silica proved to be more effective for a melt decontamination of stainless steel wastes contaminated with depleted uranium.

• Applied Biological Chemistry
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• 제40권4호
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• pp.283-288
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• 1997

1% linoleic acid를 함유하는 수용성 완충용액과 LDL(low-density lipoprotein, 1 mg protein/ml)을 함유하는 수용성 완충용액 각각에 $H_2O_2$와 $FeCl_2$를 가하여 유발된 산화과정 중 한국산 홍삼 extract(red ginseng extract; RGE)에 대한 산화방지활성을 비교물질로 ${\alpha}-tocopherol$을 사용하여, HPLC를 이용한 MDA(malondialdehyde) 정량법과 fluorometry를 이용하여 측정 비교하였다. LDL(0.25 mg protein/ml)에서 생성된 conjugated diene도 spectrometry로 측정하였다. Linoleic acid를 기질로 사용한 경우, MDA 생성량으로 비교한 산화방지효과에 있어서 1000 ppm RGE의 첨가로 71.8%의 우수한 산화저해율이 나타났으며, 이때 비교물질로 사용한 100 ppm ${\alpha}-tocopherol$의 경우에는 76.1%이었다. LDL(1 mg/ml)을 기질로 사용하였을 경우에는 RGE 200 ppm 첨가시 가장 우수한 항산화효과가 나타났으며, 이때의 산화저해율은 25.2%이었고, 100 ppm ${\alpha}-tocopherol$의 경우는 21.2%이었다. 또한 LDL(0.25 mg protein/ml)을 기질로 사용하여 생성된 c-diene을 측정한 경우에도 50 ppm RGE의 첨가로 44.2% 저해효과가 입증되었다.

• 암석학회지
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• 제18권2호
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• pp.93-114
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• 2009

옥천대 서남부에 위치한 함평 지역의 백악기 화산암류에 대하여 암석학적, 암석화학적 특성 및 조구적 위치에 대하여 야외지질조사와 주원소, 미량원소 및 희토류원소의 분석을 통하여 수행하였다. 화산암류의 $SiO_2$함량 범위는 50.8${\sim}$77.2 wt.%이며, $SiO_2$함량이 증가함에 따라 $Al_2O_3$, $Fe_2O_3\;^T$, $TiO_2$, MnO, CaO와 MgO 함량은 감소, $K_2O$함량은 증가하는 경향을 보이나, $Na_2O$함량은 경향에서 벗어나 다소 분산된다. TAS성분도와 AFM성분도에서, 함평 지역의 백악기 화산암류는 칼크-알칼리암계열에 속하며, $SiO_2$에 대한 $K_2O$의 성분도에서는 고-K 암석계열에 속한다. 특징적으로 높은 LILE/HFSE 비와 LREE 원소의 부화 현상을 보여주는 화산암류의 미량원소 함량과 희토류원소의 변화 경향은 섭입대 환경에 연관된 대륙연변호의 칼크-알칼리암의 전형적인 특성을 보여준다. Ba/Ta와 Ba/La의 비에서도 화산호 환경에서의 마그마 작용에 연관되어 있음을 지시한다. 함평지역의 백악기 화산암류는 백악기 동안 태평양형 지체구조 환경에 연관된 유라시아 대륙판의 경계부에 위치한다.

• 한국환경과학회지
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• 제17권2호
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• pp.203-210
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• 2008

The batch tests were performed to determine the ratio of Fenton reagent on diesel contaminated soil. The objective of a column test was to determine and optimize the hydrogen peroxide requirements for the remediation of a soil contaminated with diesel fuel. The batch test were done on 5 g diesel contaminated soil containing hydrogen peroxide (35%) and Iron (II) sulfate. The $H_2O_2(g):Fe^{2+}(g)$ ratio varied 1:0, 30:1, 15:1, 5:1, 1:1, with contact reaction time 120min. Initial diesel concentration were 2,000 mg/kg, 5,000 mg/kg, and 10,000 mg/kg. Average diesel removal from the contaminated soil is 97% after 2hrs. Results of this study showed possible application of without addition of iron source. In column test, treatment of a diesel-contaminated soil (initial diesel concentration: 2,000 mg/kg, 5,000 mg/kg, and 10,000 mg/kg) with hydrogen peroxide (35%) only was containing natural-occurring minerals. The time required for the column test was approximately 90min, 180min, 270min; column length was 5 em, 10 em, and 15 em. The most effective stoichiometry (final diesel cone.: $200{\sim}300mg/kg$) of 0.2 g peroxide consumed/mg diesel degraded. Further investigation is required to identify the effect of soil organic matter and soil mineral.

• 한국재료학회지
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• 제27권5호
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• pp.281-288
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• 2017

In this study, Fe-Ni slag, converter slag and dephosphorization slag generated from the steel industry, and fly ash or bottom ash from a power plant, were mixed at an appropriate mixing ratio and melted in a melting furnace in a mass-production process for glass ceramics. Then, glass-ceramic products, having a basalt composition with $SiO_2$, $Al_2O_3$, CaO, MgO, and $Fe_2O_3$ components, were fabricated through casting and heat treatment process. Comparison was made of the samples before and after the modification of the process conditions. Glass-ceramic samples before and after the process modification were similar in chemical composition, but $Al_2O_3$ and $Na_2O$ contents were slightly higher in the samples before the modification. Before and after the process modification, it was confirmed that the sample had a melting temperature below $1250^{\circ}C$, and that pyroxene and diopside are the primary phases of the product. The crystallization temperature in the sample after modification was found to be higher than that in the sample before modification. The activation energy for crystallization was evaluated and found to be 467 kJ/mol for the sample before the process modification, and 337 kJ/mol for the sample after the process modification. The degree of crystallinity was evaluated and found to be 82 % before the process change and 87 % after the process change. Mechanical properties such as compressive strength and bending strength were evaluated and found to be excellent for the sample after process modification. In conclusion, the samples after the process modification were evaluated and found to have superior characteristics compared to those before the modification.

• 한국식품영양과학회지
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• 제27권2호
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• pp.220-226
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• 1998

This study was undertaken to analyze proximate comosition, mineral contents and fatty acid composition of pure jemsosojoo(PJ) and jemsosojoo added medicinal herb(JMH). Mositure, ash, crude protein and crude fat of pure jemsosojoo were higher than those of the JMH, but carbohydrate content was higher in the JMH. Among minerals, Ca, Mg, Fe, Zn content of the JMH were higher than those of the PJ, while P and Na were higher in the PJ and those difference were significant between the PJ and the JMH(p<0.05). U/S (unsaturaed fatty acid/saturated fatty acid) ratio was higher in the JMH than those of the PJ, the ratio o fglycolipid was 1.75 in the PJ and that of neutral lipid was 3.07 in the JMH. Octadecenoic acid, hexadecanoic acid, octadecenoic acid and hexadecenoic acid were major fatty acids in the total lipids, neutral lipids glycolipids and phospolipids of the PJ and the JMH. Especially, octadecadienoic acid and octadecatrienoic acid were higher in the JMH than those of the PJ.