• Korean Architects
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• no.3 s.335
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• pp.82-87
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• 1997

이번호부터 소개되는 건축가 김중업편에서는 출생후 평양과 일본동경에서의 생활(1922~1945)을 시작으로 해방후 남한에서의 생활(1946~1951), 유네스코주최 제1회 세계예술가회의에 한국대표의 한 사람으로 참석하면서부터 르꼬르뷔제의 문하에서의 생활, 귀국후의 활발한 건축활동 시기(1952~1971) 그리고 또다시 9년간의 외국생활이후 남은 건축인생기(1972~1988)등으로 구분하여 먼저 김중업의 일생(1회:부인 김병례여사와의 대담내용을 중심으로)에 대하여 소개한다. 그리고 다음 2회와 3회에서는 필자가 김중업 선생 생전에 대담한 내용을 정리ㆍ소개하고 그의 건축가로서의 역정과 작품에 대한 필자의 해석을 싣고자 한다.

• Journal of Ginseng Research
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• v.25 no.1
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• pp.53-58
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• 2001

To clarify a significant difference between red-colored phenomena (RCP) and microbes isolated from rhizosphere soil of healthy ginseng (HES) and red-colored ginseng (RCS), we have examined growth and cellulase activities of the microbes according to pH variation and iron status. The soil microbes could not grow at pH 3.0 on the YEB medium. The growth of bacterium isolated from RCG at pH from 5.0 to 9.0 showed small differences and the growth of bacterium HES was lower than that of others. The growth of bacteria from RCS and surface soil (SUS) at pH 5.0 were also lower than that of pH 7.0 and pH 9.0. However, the bacteria isolated from red-colored ginseng (RCG) and RCS are able to grow on the medium contained 2 mM Fe$\^$3+/ at pH 3.0. Furthermore, the growth of bacterium from RCG increased about two times in the medium contained iron at pH 7.0 compared with minus iron. The cellulase activity of isolated bacteria increased two times in the medium contained 2 mM Fe$\^$3+/ compared with minus iron. The activity of extra-cellular cellulase was higher by one hundred times than that of intracellular level. The cellulase activity of the bacterium from RCS at pH 5.0 was higher by two times than that of pH 7.0. Especially, intracellular activity of the bacterium from RCS on the medium contained 2mM Fe$\^$3+/ increased about six to seven times compared with control (minus iron). Also, extra-cellular activity increased about eleven to twelve times compared with control. These results indicate that the soil microbes seem to be related iron redoxidation by proton extrusion and with cell wall digestion by secreted cellulase.

• Proceedings of the Korean Society of Soil and Groundwater Environment Conference
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• 2003.04a
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• pp.279-282
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• 2003

충적층 지하수 개발이 활발히 이루어짐에 따라 철, 망간이 충적층 지하수를 이용한 취수원 확보 시에 정수처리의 주요관심대상이 되고 있다. 이에 본 연구에서는 기존 충적층 지하수의 개발이 이루어졌거나 검토되었던 지역을 중심으로 철, 망간의 분포특성을 고찰하여 보았다. 연구지역은 크게 금강권역, 낙동강권역, 영산-섬진강권역, 한강권역으로 나누었고, 조사 관정이 밀집된 권역들은 더 세분된 지구로 나누어 연구를 수행하였다. 철의 경우, 563개의 시료가 망간의 경우, 483개 시료가 수집 분석되었다. 수집된 충적층 지하수 시료들의 철, 망간 농도를 살펴보면, 철의 경우는 전체 조사 관정의 약 27%, 망간의 경우는 약 39%가 음용수 수질기준(WHO)을 상회하였다. 본 연구에서는 철, 망간의 분포특성을 고찰하기 위하여 철, 망간 농도에 대한 다양한 통계 분석을 수행하였다 수집 분석된 철의 산술평균 농도는 2.7ppm이며, 망간의 산술평균 농도는 0.4ppm로 이들 산술평균 역시, 모두 음용수 수질 기준을 상회하는 것으로 나타났다 그러나 철 및 만간 농도의 중간 값은 각 각 50 및 20 ppb이며, 실제 이들 농도가 기하학적 분포를 한다고 가정할 경우, 이들의 대표 값인 기하평균은 모두 먹는 물 수질기준을 만족하는 것으로 나타났다.

• Proceedings of the KSLP Conference
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• 2001.11a
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• pp.175-175
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• 2001

• Applied Biological Chemistry
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• v.1
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• pp.12-20
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• 1960

고위생산답(高位生産畓) 22개(個)와 매년(每年) 호마엽고병(胡麻葉枯病)을 발생(發生)시키는 저위생산답(低位生産畓) 18개토양(個土壤)을 분석(分析)하고 활성철(活性鐵)과 열염산(熱鹽酸)에 녹는 철(鐵)의 분포상태(分布狀態)를 조사(調査)하였으며 그 결과(結果)는 아래와 같다. 1. 작토중(作土中)의 활성철(活性鐵)의 함량(含量)과 청취(聽取)한 정조수량간(正粗收量間)에는 밀접(密接)한 정상관(正相關) (${\gamma}=0.68$, 고등(高等)의 유의성(有意性)이 있음)이 있다. 2. 고위생산답(高位生産畓) 토양(土壤)의 활성철(活性鐵) 및 열염산가용철(熱鹽酸可溶鐵)은 저위생산답(低位生産畓) 토양(土壤)에서의 그것보다 현저(顯著)히 많았으며 각(各) 토양별(土壤別) I 층(層)의 그 평균함량(平均含量)과 열염산가용철(熱鹽酸可溶鐵)에 대(對)한 활성철(活性鐵)의 비율(比率)은 아래와 같다. 고위생산답(高位生産畓) 조사점수(調査點數) 활성철(活性鐵)% 활성철(活性鐵)/염산가용철(鹽酸可溶鐵) 잔적토(殘積土) 6 1.313 0.374 하성토(河成土) 9 1.334 0.335 해성토(海成土) 5 1.120 0.382 평균(平均) 20 1.224 0.359 저위생산답(低位生産畓) 조사점수(調査點數) 활성철(活性鐵)% 활성철(活性鐵)/염산가용철(鹽酸可溶鐵) 잔적토(殘積土) 5 1.15 0.370 하성토(河成土) 8 0.472 0.191 해성토(海成土) 5 1.068 0.362 평균(平均) 18 0.808 0.288 그러나 표(表)에서와 같이 잔적토(殘積土) 저위생산답(低位生産畓) 각층(各層)의 철(鐵)은 고위생산답(高位生産畓)에서 보다 낮지 않았다. 3. 해수(海水)의 영향(影響)을 받지 않은 고위생산답(高位生産畓)에서는 표층토(表層土)의 세탈(洗脫)이 적었으나 동(同) 저위생산답(低位生産畓) 및 해성토(海成土)에서는 그 세탈(洗脫)이 크고 동세탈물(同洗脫物)은 심층(心層)에 집적(集積)되여 있다. 4. 해성토(海成土)에서는 고위생산답(高位生産畓)이나 저위생산답(低位生産畓)을 막론(莫論)하고 집적층직하(集積層直下)에 활성철량(活性鐵量)이 심(甚)히 적은 층(層)이 있다. 그리고 집적층(集積層)은 고위생산답(高位生産畓)에서는 II-III층(層)(지표면(地表面)으로부터 60cm이내(以內))에 저위생산답(低位生産畓)에서는 I-II층(層)(지표면(地表面)으로부터 대개(大槪) 30cm이내(以內))에 위치(位置)한다. 5. 같은 고위생산답(高位生産畓) 및 저위생산답(低位生産畓)에서는 토성간(土性間)의 활성철함량(活性鐵含量)에 큰 차이(差異)가 없다. 6. 내산씨(內山氏)의 4개(個)기본(基本)토양형별(土壤型別)로는 동일(同一)토양형((土壤型)이라도 고위(高位) 저위생산답별(低位生産畓別)로 활성철(活性鐵)의 함량(含量)에는 차이(差異)가 크다.

• Journal of the Mineralogical Society of Korea
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• v.21 no.4
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• pp.425-434
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• 2008

Arsenic contamination in soil and groundwater has recently been one of the most serious environmental concerns. This arsenic contamination can be originated from natural or anthropogenic sources. It has been well known that arsenic behavior in geo-environmental is controlled by various oxides or hydroxides, such as those of iron, manganese, and aluminum, and clay minerals. Among those, particularly, iron (oxy)hydroxides are the most effective scavengers for arsenic. For this reason, this study characterized arsenic adsorption of magnetite which is a kind of iron oxide in nature. The physicochemcial features of the magnetite were investigated to evaluate adsorption of arsenite [As(III)] and arsenate [As(V)] onto magnetite. In addition to experiments on adsorption equilibria, kinetic experiments were also conducted. The point of zero charge (PZC) and specific surface area of the laboratory-synthesized magnetite used as an arsenic adsorbent were measured 6.56 and $16.6\;g/m^2$, which values seem to be relatively smaller than those of the other iron (oxy)hydroxides. From the results of equilibria experiments, arsenite was much more adsorbed onto magnetite than arsenate, indicating the affinity of arsenite on magnetite is larger than arsenate. Arsenite and arsenate showed adsorption maxima at pHs 7 and 2, respectively. In particular, adsorption of arsenate decreased with increase in pH as a result of electrical repulsion caused by anionic arsenate and negatively-charged surface of magnetite. These results indicate that the surface charge of magnetite and the chemical speciation of arsenic should be considered as the most crucial factors in controlling arsenic. The results of kinetic experiments show that arsenate was adsorbed more quickly than arsenite and adsorption of arsenic was investigated to be mostly completed within the duration of 4 hours, regardless of chemical speciation of arsenic. When the results of kinetic experiments were fitted to a variety of kinetic models proposed so far, power function and elovich model were evaluated to be the most suitable ones which can simulate adsorption kinetics of two kinds of arsenic species onto magnetite.

• Resources Recycling
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• v.12 no.5
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• pp.50-56
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• 2003

To be recycled iron and heat source in EAF, EAF dust and mill scale generated from steelmaking plant should be made to iron carbide. Behavior of reduction and carburization in EAF dust and mill scale is studied to get fundamental data. EAF dust and mill scale are carburized at $650^{\circ}C$ by 100% CO gas. The carbon content of iron carbide(about 9 wt,% C) is higher than that of cementite without free carbon. The 1.2 times of calculated carbon content is suitable for reduction of EAF dust. The reduction temperature is appropriate to $900^{\circ}C$ in EAF dust and $1000^{\circ}C$ in mill scale. The carburization rate of mill scale are faster than those of EAF dust. The composition of super iron carbide is almost $Fe_2$C.

• Proceedings of the Korean Ceranic Society Conference
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• 2003.04a
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• pp.52.2-52
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• 2003

• Journal of Soil and Groundwater Environment
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• v.14 no.6
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• pp.101-107
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• 2009

Carboxymethyl cellulose (CMC) as stabilizer is expected to facilitate in-situ delivery of zero-valent iron (ZVI) nanoparticles in a contaminated aquifer because it increases dispersity of ZVI nanoparticles. This work investigated the transport of CMC-stabilized ZVI nanoparticles (CMC-Fe) using column breakthrough experiments. The ZVI nanoparticles (100 mg/L Fe) were transportable through sand porous media. In contrast, non-stabilized ZVI nanoparticles rapidly agglomerate in solution and are stopped in sand porous media. At pH 7 of solution approximately 80% CMC-Fe were eluted. When the pH of solution is below 5, 100% CMC-Fe were eluted. These results suggest that the mobility of CMCFe was increased as pH decreases. In the mobility test under different ionic strengths using $Na^+$ and $Ca^{2+}$ ions, there was no signigficant difference in the mobility of CMC-Fe. Also, in the experiments of effect of clay and natural organic mater (NOM) on the mobility of ZVI, there was no significant difference in the mobility of CMC-Fe not only between 1 and 5% clay, but 100 and 1000 mg/L NOM. The results from this work suggests that the CMC-Fe nanoparticles could be easily delivered into the subsurface over a broad range of ionic strength, clay and NOM.

• Journal of the Mineralogical Society of Korea
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• v.22 no.3
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• pp.177-189
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• 2009

Iron (oxyhydr)oxides commonly form as secondary minerals of high reactivity and large surface area resulting from alteration and weathering of primary minerals, and they are efficient sorbents for inorganic and organic contaminants. Accordingly, they have a great potential in industrial applications and are also of substantial interest in environmental sciences. Goethite (${\alpha}$-FeOOH) is one of the most ubiquitous and stable forms of iron (oxyhydr)oxides in terrestrial soils, sediments, and ore deposits, as well as a common weathering product in rocks of all types. This study focused on adsorption reaction as a main mechanism in scavenging arsenic using goethite. Goethite was synthesized in the laboratory to get high purity, and a variety of mineralogical and physicochemical features of goethite were measured and related to adsorption characteristics of arsenic. To compare differences in adsorption reactions between arsenic species, in addition, a variety of experiments to acquire adsorption isotherm, adsorption edges, and adsorption kinetics were accomplished. The point of zero charge (PZC) of the laboratory-synthesized goethite was measured to be 7.6, which value seems to be relatively higher, compared to those of other iron (oxyhydr)oxides. Its specific surface area appeared to be $29.2\;m^2/g$ and it is relatively smaller than those of other (oxyhydr)oxides. As a result, it was speculated that goethite shows a smaller adsorption capacity. It is likely that the affinity of goethite is much more larger for As(III) (arsenite) than for As(V) (arsenate), because As(III) was observed to be much more adsorbed on goethite than As(V) in equivalent pH conditions. When the adsorption of each arsenic species onto goethite was characterized in various of pH, the adsorption of As(III) was largest in neutral pH range (7.0~9.0) and decreased in both acidic and alkaline pH conditions. In the case of As(V), the adsorption appeared to be highest in the lowest pH condition, and then decreased with an increase of pH. This peculiarity of arsenic adsorption onto goethite might be caused by macroscopic electrostatic interactions due to variation in chemical speciation of arsenic and surface charge of goethite, and also it is significantly affected by change in pH. Parabolic diffusion model was adequate to effectively evaluate arsenic adsorption on goethite, and the regression results show that the kinetic constant of As(V) is larger than that of As(III).