• Journal of Environmental Health Sciences
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• v.15 no.1
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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.

• Journal of Korean Society of Water and Wastewater
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• v.25 no.1
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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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• v.55 no.4
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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.

• Journal of The Korean Society of Grassland and Forage Science
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• v.30 no.1
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• pp.15-24
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• 2010

This study was conducted to investigate the effects of swine manure (SM) application with additional nitrogen (N) fertilizer on productivity of corn and environmental pollution in com cultivation soil. The experiment was conformed in lysimeter which was constructed with 30 cm diameter, and 100 cm height. Swine manures used in this study were the compost of swine manure fermented with sawdust (SMFWS) and soft rice hulls treated with high temperature and high pressure (SRH), and swine slurry (SS). The application rates of the additional N, as urea, with swine manure were 50 and 100 kgN/ha on each plot. This study was arranged in completely randomized design with three replication. DM yields in SM treatments with mineral N were increased significantly compared to those in SM treatment without mineral N (zero-mineral N) (P<0.05) and increased as the rate of mineral N application increased (P<0.05). DM yields in SMFWS and SS treatments with mineral 100 kgN/ha showed trends similar to those of chemical fertilizer (control) but higher than those of 50 kg N/ha. DM yields tended to be higher in SMFWS and SS treatments than in SRH treatment. Total N contents in SMFWS, SRH and SS treatments with mineral N were increased, compared with SM treatment without mineral N. N contents in SM treatments with mineral N were lower than those of chemical fertilizer treatment, but N content of chemical fertilizer treatment showed trends similar to that of SS treatments with mineral 100 kgN/ha. $NO_3$-N concentration in SM treatments with mineral N were increased significantly, compared to those in SM treatment without mineral N and in chemical fertilizer (P<0.05). $NH_4$-N concentrations in SMFWS and SS treatments with mineral 100 kgN/ha showed trends similar to those of chemical fertilizer, but higher than those of 50 kg N/ha. $PO_4$-P concentration in SM treatments with mineral N were increased significantly, compared to those in SM treatment without mineral N (P<0.05). $PO_4$-P concentration in chemical fertilizer treatment showed trends similar to that of SS treatments with mineral 100 kgN/ha. The concentrations of $NO_3$-N $NH_4$-N and $PO_4$-P increased as the rate of mineral N application increased (P<0.05). The concentrations of $NO_3$-N $NH_4$-N and $PO_4$-P were highly elevated in the concentrated rainy season in the early stage among experimental period. The maximum $NO_3$-N $NH_4$-N and $PO_4$-P concentrations in the leaching water were 3.46 mg/L, 1.11 mg/L and 0.14 mg/L, respectively.

• Journal of the Mineralogical Society of Korea
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• v.21 no.3
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• pp.261-269
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• 2008

A NYF-type (Nb-Y-Zr-F) Khaldzan-Buregtei pegmatite containing rare-earth metals occurs within alkali granitoid complex of the western Mongolia. The pegmatites are considered as differentiates of syenites and alkali feldpar granitic rocks, showing that their rare-earth element concentrations are enriched tens times higher than those from the adjacent alkali granitic rocks. It is suggested that econemic aspects of the pegmatites can be controlled by the magnitude of lateral and vertical extensions and local grade variation of REE-bearing pegmatites.

• Journal of Nutrition and Health
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• v.40 no.3
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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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• v.20 no.6
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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.

• Korean Journal of Materials Research
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• v.31 no.7
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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.

• Journal of Bio-Environment Control
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• v.11 no.3
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• pp.133-138
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• 2002

This study was conducted to investigate the effece of NaCl concentrations on the growth, photosynthetic rate and mineral uptake of tomato, red pepper, and egg Plant in Pot culture. The growth such as plant height, plant fresh and dry weight, root fresh and dry weight and dried matter rate was decreased as NaCl concentrations were increased. Specially, the growth inhibition of tomato and egg plant was shown at over 40 mM NaCl, and that of red pepper at 20 mM NaCl. Yield of tomato and egg Plant was reduced at over 20 U NaCl, that of red pepper at over 10 mM NaCl. Yield reduction was affected by the number of fruit at low concentration and by mean weight and number of fruit at high concentration. Photosynthetic rate, water potential and stomatal conductance were decreased as NaCl concentrations were increased. The higher the concentration of NaCl, the lower the mineral uptake such as T-N, P, K, Ca and Mg, however, the higher the content of Na and Cl.

• Asian-Australasian Journal of Animal Sciences
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• v.6 no.1
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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.