• 한국환경보건학회지
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• 제15권1호
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• pp.75-79
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• 1989

This study was carried out to investigate water quality of mineral water located in Nam san. 8 sites were pointed out by ramdom sampling and tested for 12 items in May and December 1988. The results were as follows: 1. The range of pH value in all sites was 5.4 - 6.8. 2. NH$_{3}$-N concentrations were suitable for drinking water criteria in winter season but site 1 was not for drinking water criteria. 3. NO$_{3}$-N concentrations were suitable for drinking water criteria in all samples. 4. Most of heavy metals were detected small amount, and espically zinc were detected much amount in all sites (0.01-0.32). 5. Coliform was not detected in all sites .in summer season but site 4 and 8 were detected in winter season.

• 상하수도학회지
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• 제25권1호
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• pp.7-14
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• 2011

This study was motivated by the purpose of improving the O-Index, currently used to quantify water tasty. The authors first develop the M-Index after normalizing Ca, K, and $SiO_{2}$ concentrations in the spring water, in that the concentrations are subject to their log-normal distributions. The M-Index is then compared with the O-Index based on the results of sensory tests, revealing that sensory tests are correlated with the M-Index much more than the O-Index. Furthermore, the developed index is applied to evaluate water sampled from 53 springs in Korea. It is concluded that water, sampled from five most famous springs, has high values in M-Index. In addition, water, collected from springs that are relatively accessible, contains low values, and thus is expected not to tasty good.

• Korean Chemical Engineering Research
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• 제55권4호
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• pp.443-455
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• 2017

This article provides an exclusive overview of the synthesized aragonite precipitated calcium carbonate and its applications in various fields. The last decade has seen a steady increase in the number of publications describing the synthesis, characterization and applications of calcium carbonate morphologies. Mainly, two kinds of processes have been developed for the synthesis of aragonite precipitated calcium carbonate under controlled temperature, concentrations and aging, and the final product is single-phase needle-like aragonite precipitated calcium carbonate formed. This review is mainly focused on the history of developed methods for synthesizing aragonite PCC, crystal growth mechanisms and carbonation kinetics. Carbonation is an economic, simple and ecofriendly process. Aragonite PCC is a new kind of functional filler in the paper and plastic industries, nowadays; aragonite PCC synthesis is the most exciting and important industrial application due to numerous attractive properties. This paper describes the aragonite PCC synthetic approaches and discusses some properties and applications.

• 한국초지조사료학회지
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• 제30권1호
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• pp.15-24
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• 2010

본 연구는 돈분의 발효 형태에 따른 추가적인 화학비료가 옥수수의 생산성과 이에 의한 환경오염에 미치는 영향에 대한 연구로서 lysimeter에서 옥수수에 대한 톱밥발효돈분, 팽연왕겨발효돈분 및 액상발효돈분 단독시용 및 추가적인 요소의 시용수준에 따라 $NO_3$-N $NH_4$-N 및 $PO_4$-P 용탈에 의한 환경오염에 미치는 영향을 정확히 규명하여 가축분뇨의 자원화는 물론 가축분뇨에 의한 환경오염 방지대책 수립을 하고자 수행하였다. 톱밥발효돈분, 팽연왕겨발효돈분 및 액상발효돈분에 각각 추가적인 요소의 첨가에 따른 옥수수의 건물수량은 톱밥발효돈분, 팽연왕겨발효돈분 및 액상발효돈분 단독시용구보다 유의적으로 증가하였으며 추가적인 요소시용수준의 증가에 따라 증가하는 경향이었다. 톱밥발효돈분 및 액상발효돈분에 요소 100 kgN/ha 시용했을때의 건물수량은 화학비료 시용구와 비슷한 경향을 보였으며 50 kgN/ha 시용했을때 보다는 현저하게 높았다. 톱밥발효돈분 및 액상발효돈분 단독시용했을때의 건물수량은 팽연왕겨발효돈분 단독시용구보다 현저하게 증가하였다. 톱밥발효돈분, 팽연왕겨발효돈분 및 액상발효돈분에 각각 추가적인 요소의 첨가에 따른 옥수수내 전질소 함량은 돈분뇨의 단독시용구보다 현저하게 증가하였다. 톱밥발효돈분, 팽연왕겨발효돈분 및 액상발효돈분에 각각 추가적인 요소의 첨가에 따른 전질소함량은 화학비료처리구 보다 낮았으나 액상발효돈분에 각각 추가적인 요소의 100 kgN/ha 첨가구는 화학비료 처리구와 비슷한 경향을 나타냈다. 톱밥발효돈분, 팽연왕겨발효돈분 및 액상발효돈분에 각각 추가적인 요소의 첨가에 따른 용탈수에서 $NO_3$-N 농도는 톱밥발효돈분, 팽연왕겨발효돈분 및 액상발효돈분 단독처리구와 화학비료 처리구의 보다 유의적으로 증가하였다. 톱밥발효돈분 및 액상발효돈분에 각각 추가적인 요소의 100 kgN/ha 첨가에 따른 용탈수에서 $NH_4$-N 농도는 화학비료처리구와 비슷한 경향을 보였으나 추가적인 요소의 50 kgN/ ha 처리구보다 증가하였다. 톱밥발효돈분, 팽연왕겨발효돈분 및 액상발효돈분에 각각 추가적인 요소의 첨가에 따른 용탈수에서 $PO_4$-P 농도는 돈분뇨 단독처리구보다 증가하였다 그리고 화학비료 처리구와 액상발효돈분에 추가적인 요소 100 kgN/ha 처리구는 비슷한 경향을 보였다. 그리고 $NO_3$-N $NH_4$-N 및 $PO_4$-P 농도는 추가적인 요소시용수준이 증가함에 따라 증가하는 경향을 보였으며 시험기간동안 최고 $NO_3$-N $NH_4$-N 및 $PO_4$-P 농도 각각 3.46 mg/L, 1.11 mg/L and 0.14 mg/L를 나타냈다.

• 한국광물학회지
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• 제21권3호
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• pp.261-269
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• 2008

몽골 서부 할잔-부룩테이 알칼리 복합체에서 산출되는 페그마타이트는 Nb-Y-Zr-F의 부화가 특징적인 NYF 유형의 함희유금속 페그마타이트이다. 이들 함희유금속 페그마타이트는 할잔-부룩테이 섬장암 및 알칼리 장석 화강암의 분화물로서 알칼리 화강암류에 비해 십 배 이상의 희유금속이 농집되어 있다. 할잔-부룩테이 함희유금속 페그마타이트의 경제성은 페그마타이트맥의 연장성 및 국부적 품위 변화에 의해 좌우될 것으로 생각된다.

• Journal of Nutrition and Health
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• 제40권3호
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• pp.235-241
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• 2007

The aim of this study was to define an arginine effect when added to a diet. The influence of arginine supplements on bone mineral density and content were studied in young female Sprague-Dawley rats fed either an arginine supplemented diet or control diet. Twenty four rats (body weight $83{\pm}5g$) were randomly assigned to one of two groups, consuming casein or casein with supplemented arginine diet. All rats were fed on experimental diet and deionized water ad libitum for 9 weeks. Bone mineral density (BMD) and bone mineral content (BMC) were measured using PIXImus (GE Lunar Co, Wisconsin, USA) in spine and femur 3, 6, and 9 weeks after feeding. The serum and urine concentrations of Ca and P were determined. Diet did not affect weight gain and mean food intake. The serum concentration of Ca and P were not changed by arginine supplementation. Urinary Ca excretion was significantly decreased by arginine supplementation. Spine BMD was significantly increased by arginine supplementation on 3 and 6 weeks after feeding. Femur BMD was significantly increased in the group of arginine supplementation on 3, 6, and 9 weeks. Rats fed the arginine-supplemented diet had better bone mineral content than did control diet rats in the experimental period. Therefore, arginine supplementation may be beneficial on spine and femur BMD increment in growing female rats. These are thought to be associated with an arginine-induced growth hormone release. The exact mechanism of this effect remains to be elucidated.

• Computers and Concrete
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• 제20권6호
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• pp.705-710
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• 2017

The effectiveness of mineral additives in suppressing alkali-silica reactivity has been studied in this work. Experimentation has been performed in accordance with the procedures prescribed in ASTM C 1567. In the scope of the investigation, a quarry aggregate which was reactive according to ASTM C 1260 was tested. In the experimental program, prismatic mortar specimens measuring $25{\times}25{\times}285mm$ were produced. Ten sets of production, three specimens for each set, were made. Length changes were measured at the end of 3, 7, 14 and 28 days and then expansions in percentage have been calculated. Fly ash, silica fume, and metakaolin have been used as cement replacement in different ratios for the testing of the alkali-silicate reactivity of the aggregate. In the mixes performed, the replacement ratios were 20%, 40%, and 60% for the fly ash, and 5%, 10%, and 15% for the silica fume, and 5%, 10%, and 15% for the metakaolin. Mixes without mineral additives were also produced for comparison. The beneficial effect in suppressing alkali-silica reactivity is highly noticeable as the replacement ratios of the mineral additives increase regardless of the type of the mineral additive used. Being more concise, the optimum concentrations of using silica fume and metakaolin in mortar in suppressing ASR is 10%, respectively, while it is 20% for fly ash.

• 한국재료학회지
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• 제31권7호
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• pp.386-391
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• 2021

The formation of CaCO₃ in microalgal culture is investigated and applied for effective separation of microalgae. The presence of several cationic ions in the culture medium mediates the formation of 3 types of mineral precipitates depending on the concentration of mineral precursors, Ca²⁺ and CO₃^2-, amorphous nano-flakes, rhombohedral calcites, and spherical vaterites. While amorphous phased precipitates are formed for all concentrations of mineral precursor, only calcites are formed for 30 mM solutions of mineral precursor, and mixtures of calcites and vaterites are formed for 50 and 100 mM solutions of mineral precursor. The harvesting efficiency is also dependent on the concentration of the mineral precursor: from 90 % for 10 mM to 99 % for 100 mM after 60 mins' of gravitational sedimentation. The formation of nano-flakes on the surface of microalgal cells induces the flocculation of microalgae by breaking the stable dispersion. The negatively charged surface of the microalgal cell is compatible not only with nano-flake attachment but also with the growth of calcitic crystals in which microalgal cells are embedded.

• 생물환경조절학회지
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• 제11권3호
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• pp.133-138
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• 2002

본 실험은 가지과 작물의 염 스트레스에 대한 생장 특성 및 생리적 반응을 구명하기 위하여 수행되었다. 생육단계에 따라 NaCl을 농도별로 처리한 결과는 다음과 같았다. 초장, 생체중 등 생육은 유묘기 및 영양 생장기 모두 NaCl 농도가 높을수록 모든 작물에서 억제되었다 특히 토마토 및 가지에서는 NaCl 40mM 이상에서, 그리고 고추에서는 20mM 이상에서 작물의 생육이 크게 억제되었다. 수량은 토마토 및 가지에 서는 NaCl 20 mM 이상에서, 그리고 고추에서는 10 mM 이상에서 감소하였다. 이러한 수량감소는 낮은 농도에서는 착과수의 감소에, 그리고 농도가 높을수록 착과수의 감소와 더불어 평균과중의 감소의 영향이 컸다. 광합성 속도는 NaCl 농도가 높을수록 감소하는 경향이었으며. 고추가 가장 낮았고, 토마토, 가지 순으로 낮았다. 잎의 수분포텐셜과 기공 전도도도 광합성과 같은 경향을 나타냈다. 경엽의 무기 양분 함량에서는 질소, 인산, 칼슘, 마그네슘 및 칼륨 함량은 NaCl 농도가 증가할수록 감소하였으나 Na 및 Cl 함량은 증가하였다.

• Asian-Australasian Journal of Animal Sciences
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• 제6권1호
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• pp.99-105
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• 1993

This study determined the macro-mineral levels in plants and sheep, at different times during the year, at three farms in northern China. Samples of plants, animal tissues and faeces were collected at 5 to 8 times during the year from each site. They were analysed for calcium, sodium, phosphorus, magnesium and potassium. Sodium concentrations in plants were below those recommended for optimum animal production at all sites for all or part of the year (0.01-1.66 g/kg DM). Low concentrations of sodium in faeces were measured and signs of sodium deficiency (soil ingestion) were observed on one farm. There were seasonal trends in other mineral levels in plants and animals. Plants were lowest in potassium (2.3-13.4 g/kg DM), magnesium (1.28-4.82 g/kg DM) and phosphorus (0.24-1.62 g/kg DM) in winter and spring. However, high levels of these elements were supplied in the feed supplements used at this time of the year. During the periods of rapid pasture growth, in summer and autumn, supplements of feed and salt are often not provide even though pasture concentrations of phosphorus and sodium are low. It may be at these times that sheep will be most susceptible to deficiencies of these elements.