• Journal of the Korean Wood Science and Technology
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• v.43 no.3
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• pp.320-326
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• 2015

Mechanical properties of woods are easily affected by the differences of site environment such as soil and climate changes. In this study, the relationship between mechanical properties and growth factors for Cryptomeria japonica stands in Jeollanam-do Province, Gyeongsangnam-do Province and Je-ju island was analyzed. From these plot data, bending strength, compressive strength, and shear strength were analyzed by Duncan's new multiple range test. The results of Duncan's new multiple range test analysis indicated that bending strength, compression strength, and shear strength were positively related to tree mean height, and stem number per ha, respectively, while they were inversely proportional to DBH (diameter at breast height), elevation, and soil drainage. As a result of this study, there are high correlations between mechanical properties of wood and stand characteristics of Cryptomeria japonica by the region, this findings are very useful to apply the silvicultural treatment system to produce high quality timber as a basic data on this species (distributed in southern region of Korea).

• Korean Journal of Soil Science and Fertilizer
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• v.35 no.5
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• pp.272-279
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• 2002

A field experiment was conducted to investigate the effect of N-use efficiency and rice yield by rapeseed cake(organic fertilizer) application at panicle initiation stage in machine transplating cultivation from 1999 to 2000. The rice yield increased by 4% in "50% rapeseed cake application", by 2% in "30% rapeseed cake application" at panicle initiation stage, respectively. Amount of fertilizer N uptake was high according to increasing amount of rapeseed cake application at panicle initiation stage compared with conventional treatment, but percentage recovery of fertilizer N was higher in 30% rapeseed cake application than in 50% rapeseed cake application at panicle initiation stage. Thus, this result was thought that there was more adventageous in 30% rapeseed cake application than 50% rapeseed cake application at panicle initiation stage in the fertilizer reduction or N-use efficiency respects in rice paddy.

• Korean Journal of Soil Science and Fertilizer
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• v.29 no.3
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• pp.288-296
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• 1996

The effect of shading on the mineral components, free amino acid, and fatty acid content of tea shoot was examined under different shading conditions. The results are summarized as follows. The content of Total-Nitrogen and theanine in the tea leaves was the highest in the 95% shading as 5.49% and 15580 mg/kg, respectively, while they were the lowest in the unshading. The contents of total free acid were ranged from 24670 to 30210 mg/kg, showing higher content in the 95% shading than that in the unshading. The contents of ammonium nitrogen, potassium, and magnesium were higher in the all treatments of shading than that of unshading but vise versa in calcium content. The content of total fatty acid was the highest in the 55% + 95% shading as 27990 mg/kg, while that of unshading was the lowest as 24356 mg/kg showing the increasing order of $C_{18:3}$, $C_{18:2}$, $C_{18:0}$, $C_{18:1}$, $C_{18:0}$. The quality of tea leaves was improved with the treatment of shading compared to that of unshading showing the best in the 95% shading.

• Korean Journal of Soil Science and Fertilizer
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• v.29 no.1
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• pp.8-14
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• 1996

Use of phosphate coated urea to decrease ammonia volatilization from directly seeded paddy under dryland condition at early stage was tested. Effect on urea hydrolysis was investigated through laboratory study comparing with use of thiourea, a urease inhibitor, under different water content. A field measurement of volitilized ammonia with phosphate-glycerol ammonia absorber was conducted for surface treated urea, phosphate coated urea, phosphate coated slow-release fertilizer and organic fertilizer. Through laboratory study, hydrolysis rate of phosphate coated urea at three days after treatment was lower than that of urea, however, the rate after one week was same. Thiourea addition retarted urea hydrolysis. By field measurement, ammonia volatilization was effectively reduced by use of phosphate coated urea.

• The Korean Journal of Soil Zoology
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• v.8 no.1_2
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• pp.13-16
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• 2003

Disposal possibility of raw food wastes which have various characters without any washing and composting process was tested directly using the earthworm, Eisenia andrei. The amount of feeding treatment a day by the earthworm was investigated according to input amount of 1.5 kg/m$^2$ or 3.0 kg/m$^2$ of fifteen food wastes with the different pH and EC. Earthworm disposed an average of 0.87 kg/m$^2$/day of food wastes at the constant temperature of 15$^{\circ}C$ and 1.01 kg/m$^2$/day at 2$0^{\circ}C$. The most disposal among fifteen food wastes was the food waste with pH 5.3 and EC 17.7 as 1.59 kg/m$^2$/day at 15$^{\circ}C$ and as 1.63 kg/m$^2$/day at 2$0^{\circ}C$. The least disposal was the food waste with pH 3.9 and EC 17.7 as 0.31 kg/m$^2$/day at 15$^{\circ}C$ and as 0.53 kg/m$^2$/day at 2$0^{\circ}C$. It took an average 4 days to dispose the amount of 3 kg raw food wastes at 15$^{\circ}C$ and 3.3 days at 2$0^{\circ}C$.

• Journal of the Korea Organic Resources Recycling Association
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• v.9 no.2
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• pp.77-86
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• 2001

As construction and expansion of wastewater treatment works is continuing, generation of sludge is increasing. Bur most sludge is not used appropriately but disposed by landfill dumping to sea. Furthermore direct landfilling of sludge cake containing moisture content over 75% has been legally prohibited since 2001 that's enforcement will be more strict in 2003. Such a situation means nowadays recycling of organic waste such as sludge and food waste is necessary. Composting is one of recycling methods commonly and used as an effective means of stabilizing organic waste and then compost can be used as fertilizer. However fertilizer law management which include standard of compost products and other fertilizers applied all sludge products indiscriminiately and was not flexible. So MOE has graded organic composts according to land applications to improve recycle of organic wastes. The classified organic compost which contains low contaminants has been possible to use as various purpose. This study enalyzed 30 samples which were raw materials for compost and compost products management well and to estimate the quality of compost products. Heavy metals were measured in Raw materials and OM/N, NaCl and VS were tested in compost products as well as heavy metals. As a result, approximate 10% of raw materials was not suitable to the grade A and 6.7% over the grade B of the regulation on raw materials for compost. In the case of 30 produced compost propducts approximate, 57% of composts was not compatible with the grade A and B of the regulation on composting product. The qualities of compost products were worse than raw materials, because the compost products have more regulation item raw materials have.

• Korean Journal of Medicinal Crop Science
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• v.3 no.3
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• pp.246-250
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• 1995

Scions from the one- and two-years old and the nodes of Ligusticum chuanxiong stem were used to study the rooting ability with the treatment of plant growth regulators planted to different bed soils as the alternative propagation for the present method by rhizome. The rooting ratio in the scion from the one- and the two-years old plants showed any difference, but that was ranged from 94% to 100% in the first node and from 56% to 64% in the second node from the bottom of the stem. The scion of first node from both the plants showed more than 90% in the root ratio and 16 in the number of rooting and growed more than 31cm in the root length. The Rootone-F and 250ppm of NAA were most effective for the promotion of rooting. Rooting ratios in the sand and in the mixture of vermiculite and perlite as bed soils were about 18%, but that in the cultured soil considerably decreased.

• Proceedings of the Korean Society of Soil and Groundwater Environment Conference
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• 2001.04a
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• pp.107-110
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• 2001

제철소에서 매년 대량 발생되어 주로 매립처분되고 있는 제강분진의 재활용 방안으로서, 폐수처리분야에 널리 사용되고 있는 펜톤산화공정의 반응촉매원인 Fe 공급원으로서 제강분 진의 활용 가능성에 대한 연구를 수행하였다. 본 연구에서는 포항제철소에서 제철부산물로 발생되는 제강분진을 전처리 없이 산화촉매로 사용하여 김포 수도권 매립지의 침출수 처리 공정에서 펜톤산화조에 유입되는 원수를 대상으로 과산화수소에 의한 산화처리 실험을 수행하였다. 반응은 회분식으로 수행하였으며, 일반적으로 알려진 펜톤산화반응의 주요 반응조 건인 운전 pH, 과산화수소 주입량 및 분할주입, 제강분진의 주입량 등의 변화에 따른 각 조 건별 시간에 따른 반응결과를 알아보았다. 또한 기존의 Fe 공급원으로 사용되고 있는 FeSO$_4$와 처리성능 및 적용조건에 대한 비교 실험도 수행하였다. 침출수 수질변화는 TOC (Total Organic Carbon) analyzer를 사용하여 측정한 TOC값으로 나타냈으며, pH controller 와 정량펌프를 사용하여 HCl과 NaOH주입을 통해 반응기간동안 일정 pH를 유지하였다. 본 연구결과, 최적 pH 조건인 4에서 최대 75% TOC 제거율을 나타내었으며, 대부분의 반응은 30분 이내에 이루어졌다. 주어진 실험조건에서 FeSO$_4$와 비교하여 반응속도와 처리효율에서 향상된 결과를 나타내었으며 반응 후 응집침전실험에서도 보다 높은 처리효과를 얻을 수 있었다. 결론적으로, 과산화수소/제강분진 시스템을 이용한 화학적 산화처리방법은 경제성과 처리성능에서 기존의 펜톤산화공정의 대체방안으로서 향 후 적용가능성이 높을 것으로 기대된다.g, 200 mg/kg, 300 mg/kg의 순서로 함량이 점차 감소하는 결과를 얻을 수 있었다. 이상의 결과를 종합하여 볼 때 가자 메탄올추출물은 PQ 유도독성을 신장 및 폐조직에서 효과적으로 경감시키는 것으로 나타났다.ted retailers ("sellers") must accept end-of-life items returned to them by the consumers. At the local level, Taipei City implements a pay-as-you-throw program, whereby citizens pay waste collection and treatment fees through the purchase of special trash bags approved by the Taipei City Government. However. recyclables that are separated by citizens are collected free-of-charge by the City. Taichung City and Kaohsiung City, on the other hand, enforce mandatory sorting schemes, whereby citizens face penalties if they don't separate recyclables from the trash before pick-up. These programs have resulted in a significant reduction in municipal waste. Per capita waste collected per day has dropped from 1.143

• Journal of Life Science
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• v.20 no.2
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• pp.231-236
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• 2010

Antibiotics in veterinary medicine have been used to treat disease, promote growth rate and improve feed efficiency. However, alternative sources are needed because of of bacterial resistance to antibiotics and residues of antibiotics. The present study was carried out to evaluate the effect of CS682, a fermentation product of Korean soil bacteria, on safety, growth rate and feed efficiency, and to evaluate its value as an alternative for antibiotics used as a feed additive. Two dosages of CS682 (0.1% and 1%) were fed to chickens for 28 days. The results showed that, when compared to chickens in the control group, growth and feed efficiency was improved. Also, mortality, hematology, general clinical signs and necropsy were examined. Chickens in the treatment groups showed no adverse effects. A total of 72 weaning pigs were used to confirm the effects of CS682 at one dose level (0.1%) regarding feed efficiency. Supplementation with 0.1% CS682 also resulted in improved weight gain and feed efficiency ratio. Based on these results, CS682 may be effective in improving feed efficiency safely as a feed additive.

• Molecules and Cells
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• v.40 no.12
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• pp.966-975
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• 2017

Excessive salt disrupts intracellular ion homeostasis and inhibits plant growth, which poses a serious threat to global food security. Plants have adapted various strategies to survive in unfavorable saline soil conditions. Here, we show that humic acid (HA) is a good soil amendment that can be used to help overcome salinity stress because it markedly reduces the adverse effects of salinity on Arabidopsis thaliana seedlings. To identify the molecular mechanisms of HA-induced salt stress tolerance in Arabidopsis, we examined possible roles of a sodium influx transporter HIGH-AFFINITY $K^+$ TRANSPORTER 1 (HKT1). Salt-induced root growth inhibition in HKT1 overexpressor transgenic plants (HKT1-OX) was rescued by application of HA, but not in wild-type and other plants. Moreover, salt-induced degradation of HKT1 protein was blocked by HA treatment. In addition, the application of HA to HKT1-OX seedlings led to increased distribution of $Na^+$ in roots up to the elongation zone and caused the reabsorption of $Na^+$ by xylem and parenchyma cells. Both the influx of the secondary messenger calcium and its cytosolic release appear to function in the destabilization of HKT1 protein under salt stress. Taken together, these results suggest that HA could be applied to the field to enhance plant growth and salt stress tolerance via post-transcriptional control of the HKT1 transporter gene under saline conditions.