• Korean Journal of Soil Science and Fertilizer
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• v.30 no.3
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• pp.242-247
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• 1997

This study was conducted to investigate the combined effects of oyster shell, fly ash and gypsum on rice yield and quality. The four treatments of soil amelioration were oyster shell 4, fly ash 80, fly ash 56 + gypsum 24 and oyster shell 0.8 + fly ash 40 + gypsum 24 ton/ha. Rice yield were in the order of oyster shell, fly ash and control plats. The pH, EC values and OM, Ca, $SO_4$, moisture contents of the top-soil after rice harvesting in soil amelioration treatments were increased, while Mg, Na, Fe, Zn and Al were decreased than those of control. Rice quality was the best in the fly ash plat due to lower T-N and higher Mg/K ratio.

• Korean Journal of Soil Science and Fertilizer
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• v.40 no.2
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• pp.145-150
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• 2007

This study was conducted to evaluate the application effects of phospho-gypsum fertilizer (PGF) as reclamation material in the newly reclaimed paddy fields located in Goheung and Youngam, Jeonnam province in Korea. The PGF used in this experiment was produced by Namhae Chemical Co. as the name of Soil-Saver$^{TM}$. Prior to rice transplanting, the PGF was applied as soil amendment as the amount of $3,000kg\;ha^{-1}$. The PGF increases rice plant height and number of tiller at the heading stage by 119.9 cm and 9.1, respectively, in Youngam area. The harvest index of brown rice increased up to 5 and 13% more in the PGF applied paddy field from both sites than in the non-application of PGF at paddy field before rice transplanting, and the ripening ratio in increased in both sites to 81 and 90%. Protein content of brown rice was also greater than in the non-application of PGF at the both sites. For the effects of the reclamation by PGF in the paddy field soils, we found that PGF reduced exchangeable Na to 18 and 28% for both sites, respectively, and increased exchangeable Ca and $SO_4$. And we found relatively higher amounts of $K_2O$, CaO and MgO in the rice plants from both sites applied with PGF.

• KCID journal
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• v.8 no.1
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• pp.70-79
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• 2001

This study was Performed to analyze desalinization effects of gypsum treatments in reclaimed tidal lands and to obtain the basic data for developing prediction techniques of desalinization to be applicable to reclaimed tidal lands at the beginning stage.

• Horticultural Science & Technology
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• v.34 no.4
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• pp.587-595
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• 2016

Salt stress in crops in reclaimed tidal lands can be reduced by applying soil amendments. To evaluate the effects of compost, gypsum, and phosphate on the growth of Chinese cabbage in saline-sodic soil conditions, we conducted a pot experiment in 2013 and 2014. The treatments consisted of a standard fertilizer application of a mix of compost and N-P-K fertilizer (S) and standard fertilizer applications with additional compost (S + C), gypsum (S + G), phosphate (S+P), and gypsum and phosphate (S + GP). The mean dry matter yield of cabbage in 2014 was three times as great as that in 2013, although soil EC (Electrical conductivity) in 2014 was not decreased. However, the mean ratio of sodium ion in soil solution ($SAR_{1:5}$) significantly decreased from $17.3{\pm}1.1$ in 2013 to $11.2{\pm}2.7$ in 2014. Application of gypsum had the greatest positive impact on the growth of Chinese cabbage. The S + G treatment increased dry matter yield by 7.0 (48.2) and 7.9 g/plant (16.6%) in 2013 and 2014, respectively, compared to the S treatment. Applying gypsum increased soil EC, but decreased $SAR_{1:5}$ by 14 and 38% in 2013 and 2014, respectively. The application of compost and phosphate had a small effect on the growth of Chinese cabbage. These results suggest that applying gypsum in reclaimed tidal lands can reduce the sodicity of the soil and improve crop growth.

• Korean Journal of Environmental Agriculture
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• v.28 no.1
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• pp.25-31
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• 2009

The effect of application of gypsum (G), popped rice hulls (PRH), and zeolite (Z) in exchangeable cations concentrations of reclaimed tideland soil in Kyehwado was investigated for 3 years from 2004 to 2006 in a pot experiment with bermuda grass (Cynodon dactylon). Treatments with three soil conditioner and with three applications were established with three replications; G1 (1,550 kg $10a^{-1}$), G2 (3,100), and G3 (6,200) for gypsum, H1 (1,000), H2 (2,000), and H3 (3,000) for PRH, and HZ1 (200), HZ2 (400), and HZ3 (800) for co-application of zeolite with PRH at the 1,500 kg $10a^{-1}$. At 60, 90, 120 days after treatment (DAT), exchangeable cations ($K^+$, $Na^+$, $Mg^{2+}$, and $Ca^{2+}$) were analyzed Gypsum application significantly decreased $k^+$, $Na^+$, $Mg^{2+}$ in the soil probably due to exchange and subsequent leaching of these cations by $Ca^{2+}$ from the gypsum applied. Overall, $K^+$ concentration was gradually decreased by continuous application of soil conditioners and was in the order of 2004>2005>2006 regardless of the kinds and application rate of soil conditioners. Comparing $K^+$ concentrations among the soil conditioners in the same year, its concentration was in the order of gypsum$Na^+$ concentration; i.e. $Na^+$ concentration was in the order of gypsum$\ll$PRH$Mg^{2+}$ also showed a similar pattern to $Na^+$. Gypsum application significantly increased $Ca^{2+}$ concentration and in the gypsum treated soil $Ca^{2+}$ concentration increased with years.

• Korean Journal of Environmental Agriculture
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• v.30 no.3
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• pp.243-251
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• 2011

BACKGROUND: Gypsum($CaSO_4{\cdot}2H_2O$) is known as an ideal amendment to improve soil quality of the reclaimed coastal land. Since gypsum has very high concentration of electron acceptor like ${SO_4}^{2-}$, its application might be effective on reducing $CH_4$ emission during rice cultivation, but its effect has not been studied well. METHODS AND RESULTS: The effect of gypsum on $CH_4$ emission and rice growth characteristics was studied by pot test, which was packed by reclaimed paddy soils collected from Galsa, Hadong, Gyeongnam province. Chemical-grade gypsum was applied in two soils having EC 2.25 and 9.48 dS/m at rates of 0, 0.5, 1.0 and 2.0%(wt/wt). $CH_4$ emission was characterized a week interval by closed chamber method during rice cultivation. $CH_4$ emission rate was significantly decreased with increasing salt accumulation and gypsum application levels. With increasing gypsum application, dissolved ${SO_4}^{2-}$ concentration in the leachate water was significantly increased, which might have suppressed $CH_4$ production in soil. Total $CH_4$ flux was dramatically decreased with increasing gypsum application. In contrast, rice yield was increased with increasing gypsum application and then achieved maximum productivity at 1.0% gypsum application in two soils. CONCLUSION(s): Gypsum is a very good soil amendment to suppress $CH_4$ emission in reclaimed coastal paddy soils, and improve rice productivity and soil properties. The optimum application level of gypsum is assumed at ca. 1% to improve soil productivity with reducing effectively $CH_4$ emission during rice cultivation.

• Korean Journal of Soil Science and Fertilizer
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• v.43 no.5
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• pp.764-769
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• 2010

We investigated influence of continious application of gypsum (G: $CaSO_4{\cdot}2H_2O$), popped rice hulls (H) and zeolite (Z) on soil aggregation of reclaimed sandy loam soils. The application rates amended to fine sandy loam from reclaimed soils at Kyehwado were varied as follows:1550 (G1), 3100 (G2), 6200 (G3), 1000 (H1), 2000 (H2), 3000 (H3), and 200 (HZ1), 400 (HZ2) and 800 (HZ3) added to 1500(H) kg $10a^{-1}$, respectively. Soil aggregates were analyzed for 60, 90 and 120 days after treatments (DAT). At 60 DAT, The amount of aggregate from soil samples treated with gypsum was slightly increased with G1 while the aggregation was decreased by 4.66% for G3 for soil aggregates than thar of control. The treatments of H or HZ were effective in soil aggregation. The effect of treatment was in the order of H > HZ > G. At 90 DAT, increasing amount of gypsum attributed to decrease in soil aggregates. Therefore, we could conclude that suitable amounts of gypsum for soil aggregation in fine sandy loam might be 1550 kg $10a^{-1}$ or less. H1 increased aggregation by 7% for aggregate size between 1.0 and 2.0 mm. HZ1 was most effective in aggregation by 52.78% among the treatments while H2 and HZ3 51.50% and 48.51% at 120 DAT, respectively. As a result, we found that the effect of the treatment for soil amendments was in order of H > HZ > G.

• Journal of the Korean Crystal Growth and Crystal Technology
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• v.7 no.4
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• pp.673-680
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• 1997

NaOH, $Na_2CO_3, CaO, Ca(OH)_2$ and $CaCO_3$ are widely used counteractives for neoutralizing the waste sulphuric acid produced during the metal surface treatment process and/or the metal refining process. To reduce the tremendous expenses for the neutralization treatment of the waste sulphuric acid, the sludge from calcination plant and the stainless refining dust in POSCO (Pohang Iron ＆ Steel co. Ltd.) was utilized. For the sludge, it will be effective to use calcined and then hydrated sludge in strong acid region (pH<2) and to use the sludge itself in weak acid region (pH>2), The gypsum, the by-product of this treatment, was tested to fit the industrial standard of gypsum, so it is expected that it will solve the lack of gypsum supply. For the stainless refining dust, the phase and the morphology of produced gypsum from waste suiphuric acid neutralization was compared with those from pure sulphuric acid. Because of high reactivity and reaction temperature, $CaSO_4$ non-hydrate was obtained in pure sulphuric acid. But $CaSO_4$ dihydrate was obtained in waste sulphuric acid. It is also judged to be a good material for a counteractive of the waste sulphuric acid.

• Maxillofacial Plastic and Reconstructive Surgery
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• v.27 no.3
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• pp.218-225
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• 2005

본 연구의 목적은 치아 회분말과 연석고 및 알긴산을 혼합하여 이식한 후 초기 골 형성을 알아보는 데 있다. 백서 30마리의 두개골에 8mm 직경의 골결손부를 형성한 후 인간의 치아 회분말과 연석고 및 알긴산을 혼합하여 이식한 후 대조군, 치아 회분말과 연석고 처치군, 그리고 치아 회분말과 연석고 및 알긴산 혼합 처치군에서 각각의 골 결손부 치유과정을 조직병리학적, 조직형태계측학적으로 비교 관찰하였다. 통계학적으로 주간 변화(4주, 8주)는 유의하지 않았고, 각 그룹 간에 있어도 치아 회분말과 연석고 처치군과 치아 회분말과 연석고 및 알긴산 혼합 처치군 간 모두(4주, 8주) 유의한 차이가 없었다. 그러나 이들 치아 회분말과 연석고 처치군과 치아 회분말과 연석고 및 알긴산 혼합 처치군은 대조군에 비해서는 유의하게 우수한 신생골 형성을 보였다. 비록 통계학적으로는 치아 회분말과 연석고 처치군과 치아 회분말과 연석고 및 알긴산 혼합 처치군이 유의한 차이를 보이지 않았지만 치아 회분말과 연석고 및 알긴산 혼합 처치군에서 보다 더 우수한 신생골 형성 경향을 보였다. 뿐만 아니라, 신생골의 내용면에서도 치아 회분말과 연석고 및 알긴산 혼합 처치군에서 좀더 많은 신생 직조골의 융합이나 골 소주형성이 관찰되어 신생골의 형성 및 성숙에 알긴산이 역할을 담당하는 것으로 사료되었다. 결론적으로 골결손부 치료 방법으로 치아 회분말과 연석고 처치군 또는 치아 회분말과 연석고 및 알긴산 혼합 처치로 결손부에 이식하는 것은 신생골 형성의 양적, 질적 개선에 통계학적으로 유의하며, 알긴산을 이식재와 함께 처리한 경우에 신생골 형성의 양적, 질적 개선에 도움을 줄 수 있을 것으로 사료된다.$1^{\circ}C$ 냉수로 세척하고 PETE tray로 포장하여 $4^{\circ}C$로 저장한 경우 깻잎 고유의 초록색과 향을 유지하고 있어 저온냉수 세척과 tray 포장이 세척 청경채의 선도 유지에 효과가 있는 것으로 나타났다.1%,\;pendimethalin\;1.3{\sim}2.9%$ 및 $3.8{\sim}10.8%,\;ethoprophos\;0.6{\sim}2.7%$ 및 $0.1{\sim}0.3%$이었다. 인공강우실험 후 공약의 토심별 분포를 살펴 본 결과 alachlor와 ethopropho는 토심 $10{\sim}15cm$까지 이동하였고, ethalfluralin과 pendimethalin는 대부분 토심 5 cm 이내에 잔류하였다. 경사도 30%의 경우가 10%에 비하여 각 농약의 유실량이 $0.2{\sim}1.9$ 배 증가하였는데 유출수에 의한 농약의 유실량 차이는 유출수 중 농도 차이로 판단되며, 유실토양에 의한 농약 유실량 차이는 토양 유실량과 관계되는 것으로 생각되었다. 농약의 강우에 의한 유실은 복잡하게 작용하는 많은 환경적 요인에 의하여 영향을 받지만 정교하게 구성된 환경 시나리오에 의하여 예측 가능할 것으로 판단되었다.고 도라지는 물에 우려 푹 삶았고, 감자, 송이 등은 잘게 썰어 쌀과 함께 밥을 조리하였다. 4. 약선 음식조리방법 약선음식의 재료는 평상시 식생활에 사용되고 있던 식품들의 기능성분과 약이성을 이용하여 만성적인 질병과 급성적인 복통 설사 등에 재료의 전처리를 통해 죽으로 많이 이용하였다. 특히 곡류 등은

• Journal of the Korea Organic Resources Recycling Association
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• v.21 no.2
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• pp.41-50
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• 2013

We investigated influence of continuous application of gypsum(G:$CaSO_4{\cdot}2H_2O$), popped rice hulls(H) and zeolite(Z) on soil aggregation of reclaimed silt loam soils. The application rates amended to silt loam from reclaimed soils at Saemangeum of Mangyeong were varied as follows; 1550(G1), 3100(G2), 6200 (G3) gypsum kg/10a, 1000(H1), 2000(H2), 3000(H3) popped rice hulls kg/10a, and 200(HZ1), 400(HZ2), 800(HZ3) zeolite kg/10a added to 1500 popped rice hulls kg/10a, respectively. In addition, the bermuda grass was growing, and the soil aggregates were analyzed for 60, 90 and 120 days after treatments(DAT). At 60 DAT, the effect of treatment was in order of G>H${\geq}HZ$, and the 1550kg/10a(G1) was the highest as 52.48%. At 90 DAT, the effect of treatment was also in order of G>H>HZ. Those was 3.78-3.12, 2.03-3.03 and 1.79-2.57 times in compared with the control, respectively. At 120 DAT, the effect of treatment was similar continued in order of G>H>HZ. Those was 3.00-2.20, 1.06-1.64 and 0.92-1.23 times in compared with the control, respectively. In conclusion, we found that the continuous application for two year of gypsum, popped rice hulls and zeolite was excellent above the 1 year, and the effect of the treatment for soil amendments of reclaimed silt loam soil was excellent in order of G>H>HZ.