• Journal of Environmental Science International
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• v.10 no.4
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• pp.275-280
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• 2001

In an attempt to evaluate the possibility of producing an organic fertilizer using sediments from coastal farming areas, the chemical composition, bacteriological quality and heavy metals in the sediments alkalized by conditions : a 1:4 mixture of dry sediment to food wastes and the addition of 30% quicklime to the mixture. According to the classification standard for compost constituent by Higgins, all composts had a low or intermediate grade in T-N and $K_2O$ content, a low grade in $P_2O_5$ and a high grade in CaO and MgO content. Stabilization by quicklime and magnesium hydroxide is likely to inhibit th bacterial decomposition of organic matter and the actigity of pathogenic organic. Raising the pH of stabilized sediment to 12 for 2 hours(PSRP criteria of EPA) allowed 99.99% of the coliform group, fecal group and viable cell count to be reduced. the results suggested that the crude fertilizer produced by alkaline stabilization method was innoxious and thereby the sediments from coastal farming areas could be used as organic fertilizer.

• Journal of Environmental Science International
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• v.24 no.5
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• pp.615-622
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• 2015

East Asia is characterized by anthropogenic emissions resulting from the large population and fast economic growth of this region. Since the prevailing wind is westerly and northwesterly, emissions from Ul-jin can be expected to contribute to acidic deposition increase in downwind direction. Aerosols collected at the near coast site, Uljin geun, gyungbook and were analyzed for $NH_4{^+}$, $Mg^{2+}$, $Na^+$, $Ca^{2+}$, $Cl^-$, $SO_4{^{2-}}$, and $NO_3{^-}$ from Aug. 2012 to Feb. 2013. The seasonal averaged aerosol concentration showed the highest potassium and calcium ion in winter and the highest ammonium ion due to a meadow and high solar intensity in summer. Sodium and chloride ion showed the same ratio all seasons and sulfate and nitrate species showed the maximum value in winter Chemical components of aerosols collected at the near coast site, Uljin geun, gyungbook were lower by 16 to 73% than those collected at other similar environment site such as kanghwa, yangyang. Comparing air quality data at the near coast site, Uljin geun, gyungbook, There was found that Uljin coast site is less influenced by the sea salts(potassium, magnesium, calcium) and nss-$SO_4{^{2-}}$ percentage is 3~13% higher than similar condition site.

• Korean Journal of Soil Science and Fertilizer
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• v.46 no.6
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• pp.530-535
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• 2013

This study was carried out to investigate the effect of slurry composting and biofiltration (SCB) liquid manure application on shoot growth, fruit qualities and soil chemical properties in peach orchard. SCB liquid manure was fertigated ten times from April to October in SCB plot, whereas chemical fertilizer was treated two times as basal and additional fertilizers in control plot. The shoot growth, leaf nitrogen and potassium content, soil exchangeable K, fruit weight and yield were higher in SCB plot than in control. Soluble solid content and acidity, soil organic matter, soil available phosphate and soil exchangeable Mg showed no significant difference between treatments, and the leaf calcium and magnesium content were lower in SCB plot than in control. In conclusion, fertigating SCB liquid manure in peach orchard has positive effects on fruit weight and yield, and it is suggested that periodical soil testing is needed because of the possibility of K accumulation in SCB liquid manure treated soil when the orchard is fertigated based on the soil nitrogen content.

• 한국신재생에너지학회:학술대회논문집
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• 2010.11a
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• pp.89.2-89.2
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• 2010

고체산화물 연료전지는 $800{\sim}1000^{\circ}C$인 고온에서 작동하므로 적용되는 밀봉재의 요구조건은 매우 중요하다. 본 연구에서는 SOFC 밀봉재로서 $SiO_2-B_2O_3-RO$계 결정화 유리를 선정하였으며 작동온도 부근에서 결정화를 유도하여 고온점성유동을 제어하고자 하였다. 따라서 $SiO_2-B_2O_3-RO$계에 RO인 CaO, SrO, BaO, MgO를 상호 치환하였을 때 결정상의 생성, 생성온도, 생성결정의 종류가 sealing 특성에 어떠한 영향을 주는가를 검토하였다. 결정화유리를 $800^{\circ}C$로 유지하였을 때 생성되는 주 결정상은 Calsium silicate, Strontium silicate, Barium silicate, Magnesium silicate이였으며 Strontium silicate 의 생성속도가 가장 빨랐으며 결정상은 불산으로 에칭하여 SEM으로 관찰하였다. Barium silicate를 유도한 결정화 유리가 $800^{\circ}C$에서 1000시간 유지하였을 경우 가장 내화학성이 우수하며 강도값도 154MPa로 가장 높았다. 또한 부분 결정화를 통해 $800^{\circ}C$ 점성유동이 제어됨을 고온현미경을 통해 관찰하였다.

• Korean Journal of Soil Science and Fertilizer
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• v.46 no.6
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• pp.452-457
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• 2013

To obtain the useful data related to optimum nutrient management technique for pesticides-free jujube cultivation, nutrient contents of jujube leaves and fruits and the selected chemical properties of jujube orchard soils were investigated at 9 different orchards with pesticides-free cultivation in Boeun, Chungbuk, Korea. Soil and jujube leaf samples were collected from the different orchards in July and October, and jujube fruit samples were taken in October, 2012. Soil available $P_2O_5$ contents in the optimum level for jujube cultivation were 11% and 33% of total samples in July and October, respectively, but 56% of total samples was higher than the optimum level in both July and October. Exchangeable K and Ca ion contents were 44% and 67% of total samples, respectively, in both July and October, whereas exchangeable Mg ion content was 100% and 56% of total samples in July and October, respectively. Nutrient contents in jujube leaves were higher than those in fresh fruits. In addition, total nitrate, potassium and magnesium contents in the jujube leaves were higher in the samples collected in July than in October.

• Journal of the Microelectronics and Packaging Society
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• v.25 no.2
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• pp.9-17
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• 2018

Aluminum (Al) and its alloys have been used widely in a variety of industries such as structural, electronic, aerospace, and particularly automotive industries due to their lightweight characteristic, outstanding ductility, formability, high oxidation and corrosion resistance, and high thermal and electrical conductivity. Al have different kinds of alloys according to the various additional elements system and they should be selected properly depending on their effectiveness and suitability for their particular purpose. The major elements for Al alloys are silicon (Si), magnesium (Mg), manganese (Mn), copper (Cu), and zinc (Zn). In order for Al alloys to use for each industry, it is necessary to study of Al to Al joining and/or the Al to dissimilar materials joining to combine the individual parts into one. Many studies on joining technologies about Al to Al and Al to dissimilar materials have been performed such as press joining, bolted joint, welding, soldering, riveting, adhesive bonding, and brazing. This study reviews a variety of Al alloys and their joining method including its principles and properties with recent trends.

• Journal of Environmental Science International
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• v.24 no.10
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• pp.1253-1264
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• 2015

This study assessed the fertilizing value of struvite deposit recovered from swine wastewater in cultivating Chinese cabbage. Struvite deposit was compared with commercial fertilizers: complex, organic and compost to evaluate the fertilizing effect of struvite deposit. Laboratory pot test obviously presented that the struvite deposit more facilitated the growth of Chinese cabbage than organic and compost fertilizers even though complex fertilizer was the most effective in growing Chinese cabbage. It was revealed that the growth rate of Chinese cabbage was simultaneously controlled by phosphorus (P) and potassium (K). Also, the nutrients such as nitrogen (N), P, K, calcium (Ca) and magnesium (Mg) were abundantly observed in the vegetable tissue of struvite pot. Specifically, P was the most abundant component in the vegetable tissue of struvite pot. Meanwhile, the utilization of struvite as a fertilizer led to the lower accumulation of chromium ($Cr^{6+}$) than other pots, except for compost fertilizer pots, and no detection of cadmium (Cd), arsenic (As) and nickel (Ni) in the Chinese cabbage. The experimental results proved that the optimum struvite dosage for the cultivation of Chinese cabbage was 2.0 g struvite/kg soil. On the basis of these findings, it was concluded that the struvite deposits recovered from swine wastewater were effective as a multi-nutrient fertilizer for Chinese cabbage cultivation.

• Applied Biological Chemistry
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• v.32 no.4
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• pp.441-443
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• 1989

The major kernels$(7{\sim}10\;mesh)$ of naked barley were pearled to give an average yield for each pearling of about 5% flour, with 70% of the naked barley left as residual kernel. The contents of protein, fat and ash were in the highest in the fraction of 1,2 and 3, respectively. These fractions contained 1, 4 times of protein, 3.16 times of fat and 3.08 times of ash more than those values of original kernel. Residual kernels contained 62% of protein, 38% of fat and 35% of ash in the original kernel. Among minerals, the content of Ca, Na, Fe and Mn were in the highest in fraction 1 ; P, Mg and Zn in fraction 2 ; and K and Cu in fraction 3. Concentrations of these minerals were the lowest in the residual kernel. Magnesium showed the deepest concentration gradient, while iron was evenly distributed within the kernel.

• Korean Journal of Soil Science and Fertilizer
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• v.45 no.1
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• pp.83-85
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• 2012

The causes of blossom-end rot (BER) are still not understood clearly, although there was a lot of research on the development of BER over 100 years. This experiment was conducted to investigate the influence of Ca content of fruit on the incidence of BER in red pepper. BER affected fruits and healthy fruits had been harvested and the samples were divided into two parts, the upper and the lower, for chemical analysis to determine the content of mineral nutrients in the tissue. The content of nitrogen (N), phosphorus (P), potassium (K) and magnesium (Mg) was higher in the BER affected fruits and the difference of each nutrient content was revealed much larger in the lower part of the fruit but there were no significant differences in calcium content between the BER and the healthy fruits of red pepper, in this experiment. The results indicate that it is difficult to find a certain relation between the calcium content of the fruit and the occurrence of blossom-end rot.

• Korean Journal of Veterinary Research
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• v.48 no.4
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• pp.451-455
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• 2008

Body weights and blood biochemical values in chickens infected with reticuloendotheliosis virus (REV)-HI, a Korean isolate, were studied. REV-HI causes severe body weight depression in chickens inoculated but not in chicken contact-infected. Body weights of infected chickens in 3, 4, and 5 weeks after infection were 78%, 76% and 65% of those of control respectively. Blood glucose levels in REVinfected chickens were extremely high compared with those in control (226 $\geq$ 21 vs. 814 $\geq$91.3 mg/dl in week 2) during the experiment period. Triglyceride levels in REV-infected chickens were significantly higher in week 2 and 3, whereas in week 4, REV-infected chickens showed significantly lower levels than the control. Blood lipase, amylase and alkaline phosphatase levels of REV-infected chickens in week 2 were significantly higher, whereas cholesterol, magnesium and calcium values in week 4 were significantly lower than the control. Other blood biochemical values such as alkaline aminotransferase, aspartate aminotransferase, and $\gamma$-glutamyltransferase were nonsignificantly different from the control. These above results suggest that weight depression by REV may be related with increase of blood glucose, which indicated that REV-infected chickens could not use blood glucose as energy source.