• Korean Journal of Soil Science and Fertilizer
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• v.13 no.3
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• pp.77-83
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• 1981

In order to obtain an imformation on the exchangeable potassium and it's activity ratio to other cations in wet paddy top soil grown by rice, soil samples were taken from bottomless middle size (60cm in dia, and height, respectively) round concrete pot being car ride out with an experiment on the split application of potassium in relation to lime and analysed. The pot experiment was being conducted from 1974 at a farm of the City University of Seoul and the wet soil samples were taken from the paddy in the year of 1976. The samples were extracted with $0.1N-AlCl_3$ solution and analysed regarding the elements. Results obtained are as follows : 1. Less exchangeable potassium was extracted from the soils limed than those unlimed when the same amount of potassium was applied immediatly after flooding. However, when the Potassium was applied two weeks after flooding, the reverse was observed. The fact that the exchangeable potassium is increased in the case that potassium fertilizer applied two weeks after flooding explained as due either to the prohibiting effect of iron or less abserption of potassium by the crop. 2. A remarkable decrease of exchangeable potassium of soils was observed during the vigorous growth stage of rice. 3. The activity ratio of $\frac{K}{(Fe^{{+}{+}}){\frac{1}{2}}}$ was remarkabley low after July 16th at which the soil was considerably reduced. 4. The activity ratio $\frac{K^+}{NH^+}$ of limed soil lasted highly until July 16th. It may be resulted from slow progress of ammonification caused by high pH. 5. A positive correlation was found between $Fe^{{+}{+}}$ and $Ca^{{+}{+}}$ under reduced condition. But there was no correlation between $Fe^{{+}{+}}$ and $K^+$ or $NH^+_4$, because that the concentrations of $K^+$ and $NH^+_4$ in soil fluctuates during growing season.

• Korean Journal of Soil Science and Fertilizer
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• v.30 no.1
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• pp.56-61
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• 1997

A study was carried out to find out the basic information in physical properties for selection and manufacturing the good seedling media through the analysis of the physical properties, such as particle size, water retention and three phases of the major horticultural substrates. Easily available water(EAW), the water contents between 1kPa and 5kPa water potental, was highest in peatmoss with 39%, and perlite 34.0%, vermiculite 16.9%, but the values of osmunda and bark were lower than 4.8%. Water buffering capacity(WBC), the water content between 5kPa and 10kPa, was 6.1% in peatmoss and 2.3% in vermiculite but it was lower than 1.0% in other substrates. To adjust the suitable range of water potential at crossing point of water and air curves to 1.5~2.5kPa, more finer materials were needed in osmunda and bark, and more coarser materials must be added to peatmoss, perlite and vermiculite. Water potentials of substrates in saturated pot condition were equivalent to 2.2kPa in peatmoss and others were ranged in 1.0kPa to 4.3kPa of water potential in pressure chamber.

• Korean Journal of Plant Resources
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• v.32 no.5
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• pp.486-498
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• 2019

This study was conducted to investigate the leaf growth and flowering characteristics of 85 Hosta cultivars. The 85 cultivars were grown in a pot in Useful Plant Resources Center in Yangpyeong, Korea. H. 'Abiqua Blue Crinkles', H. 'Abiqua Drinking Gourd', H. 'Dancing in the Rain', H. 'Elegance', H. 'Inniswood', and H. 'Venus' were classified as a large size group (> 50 cm), while 27 cultivars including H. 'Abby', H. 'Birchwood Parky's Gold', H. 'Blue Cadet', and H. 'Blue Edge' were classified as a small size group (< 20 cm). The others were classified as a medium size groups. 79% of Hosta cultivars had leaf variegation. Leaf variegation type was divided into 5 types (standard, marginata, mediovarigata, albomaculata, striata). Among them 31 cultivars including H. 'Abby', H. 'Abiqua Moonbeam', and H. 'Atlantis' has a variegation type of marginata in the leaf. 36 cultivars including H. 'Abby', H. 'Abiqua Drinking Gourd', and H.'Abiqua Moonbeam' bloomed in late May and 9 cultivars including H. 'Black Hills', H. 'Boeun', and H. 'Fragrant Bouquet' started to flower on late August. Most flowers were below 3.0 cm in length, while H. 'Avocado' was longest on 10.0 cm. Most flowers have a lavender color group (63.5%), and 14 cultivars of Hosta showed white color group (16.5%). 12 cultivars including H. 'Blue Mouse Ears', H. 'Captain Kirk', and H. 'Fragrant Bouquet' had the fragrance in their flowers. H. 'Cherry Berry' and H. 'Revolution' had a colorful stalk, red and yellow, respectively.

• Resources Recycling
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• v.20 no.3
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• pp.68-76
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• 2011

For the separation of aluminum and iron from platinum mixtures, extraction resins were synthesized and separation efficiencies were compared with those by commercial one, $P_{204}$. During synthesis, the suspension polymerization method was adopted with D2EHPA as an extractant. Also, benzoyl peroxide as a starter was divided into 3parts and injected for the uniform size and dispersion of resin particles. Comparison tests resulted in 100% separation of Fe and Pt for both synthetic and $P_{204}$ resins. In case of Al and Pt, synthetic and $P_{204}$ resin gave extraction efficiencies of 99.9% and 98.9%, respectively. Difference in extractant contents of synthetic resin(61.8%) and $P_{204}$(60%) was considered to give differences in separation efficiencies of aluminum and iron elements. For both resins, separation efficiencies of Al and Fe increased up to $55^{\circ}C$. According to FT-IR analyses of both resins, specific peaks of D2EHPA and crosslinked polystyrene were identified at the wavenumber of $1000cm^{-1}$ and $2900cm^{-1}$ respectively.

• Korean Journal of Soil Science and Fertilizer
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• v.45 no.6
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• pp.1094-1099
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• 2012

Green manure cultivation affects soil productivity and nutrient conservation in paddy soil at winter season. This study was to evaluate nitrogen behavior released from chinese milk vetch (CMV) as green manure by using stable $^{15}N$ trace during rice cultivation. The CMV used in the experiment was 29.9 of C/N ratio and 14.1 g N $kg^{-1}$ ($^{15}N$ 0.388 atom % excess) and was applied at rates of 10 and $30Mg\;ha^{-1}$ in pot of 1/2000a size. Rice growth and N uptake increased with higher levels of CMV application at harvesting stage. Among total N uptake, 14.6 and 26.8 % of nitrogen was released respectively from the two different rates of CMV application. Stable $^{15}N$ recovery by rice biomass was 60%, 54% to the $^{15}N$ input, respectively, of CMV application, which decreased in order of grain, root, and straw of rice biomass. Total N content in the soil after rice harvest was 1.9 and 2.1 g N $kg^{-1}$, respectively, with increasing N input by the different rates of CMV application and the rate of $^{15}N$ recovery derived from CMV in the soil was 3.8 and 4.8 %, respectively. N input by CMV application induced rice growth and productivity during rice cultivation. However, it might need proper managements to reduce N loss because about 36-41 % of nitrogen was lost from N input by CMV application.

• Journal of Korean Society of Environmental Engineers
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• v.30 no.1
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• pp.90-96
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• 2008

In order to meet the stringent requirement of sludge disposal and to find ecological alternative, aerobic digestion coupled with alkaline pretreatment was studied. The treated sludge was tested for the potential of liquid fertilizer. In the aerobic digestion, it was obvious that the performance of digester B(fed with the sludge pretreated by NaOH) was better than that of digester A(fed with raw sludge) in terms of COD and SS removal. SS and VSS removal rates in digester B were 66% and 69%, respectively. At 5 days, TSS removal rate reached 47% in the digester B, which was 71% of final TSS removal rate. It revealed that the pretreatment process can shorten the retention time of aerobic digestion. 94.1% of TCOD in the raw sludge was reduced by alkaline pretreatment and aerobic digestion. Final SCOD was in the range of 220$\sim$230 mg/L implying the sludge was stabilized. Nitrification and pH drop were observed in the aerobic digestion. Final nitrate concentrations in digester A and B were 445.4 and 223.1 mg/L and final pH in digester B was 3.0. Biological assays reported that leaf size of cucumber seedling increased with nitrate concentration and sludge to soil ratio. The sludge treated by alkaline and aerobic digestion promoted the growth of seedling leaf and stem remarkably compared to raw sludge. In contrast, the aerobically digested sludge without pretreatment improved leaf growth and inhibited stem growth.

• IMMUNE NETWORK
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• v.3 no.3
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• pp.219-226
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• 2003

Background: Phage display is the most widely used technique among display methods to produce monoclonal antibody fragment with a specific binding activity. Having a large library for efficient antibody display/selection is quite laborious process to have more than $10^9$ members of transformants. To overcome these limitations, several in vitro selection approaches have been reported. Ribosome display that links phenotypes, proteins, directly to genotype, mRNA, is one of the in vitro display methods. Ribosome display can reach the size of scFv library up to $10^{14}$ molecules and it can be further diversified during PCR steps. To select the high affinity scFv from one pot library, we established ribosome display technique by modifying the previously reported eukaryotic translation system. Methods: To establish the antibody selection system by ribosome display, we used 3D8, anti-DNA antibody. A 3D8 scFv was synthesized in vitro by an in vitro transcription-translation system. The translated 3D8 scFv and the encoding 3D8 mRNA are connected to the ribosome. These scFv-ribosome-mRNA complexes were selected by binding to their specific antigens. The eluted mRNAs from the complexes are reverse transcribed and re-amplified by PCR. To apply this system, antibody library from immunized mouse with terminal protein (TP)-peptide of hepatitis B virus DNA polymerase TP domain was also used. This TP-peptide encompasses the 57~80 amino acid residues of TP. These mRNA/ribosome/scFv complexes by our system were panned three times against TP-peptide. The enrichment of antibody from library was determined by radioimmunoassay. Results: We specifically selected 3D8, anti-DNA antibody, against ssDNA as a model system. The selected 3D8 RNAs sequences from translation complexes were recovered by RT-PCR. By applying this model system, we enriched TP-peptide-specific scFv pools through three cycles of panning from immunized library. Conclusion: We show that our translating ribosome complexes are well maintained and we can enrich the TP-specific scFv pools. This system can be applied to select specific antibody from an antibody library.

• Journal of Bio-Environment Control
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• v.26 no.4
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• pp.242-248
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• 2017

This study was conducted to develop a cylindrical paperpot manufacturing equipment which is capable of continuously producing paperpots with a constant size. The equipment consists of the soil supply part, the paper supply part, the pot manufacturing part, the paperpot cutting part and its process for manufacturing paperpot from the soil supply to the paperpot cutting is continuously performed. As a result of the performance test using this equipment, we suggest that the optimal moisture content and injection pressure to supply soil are 50%~60%, and 0.5 Mpa respectively. Moreover the appropriate temperature for adhesive strength is $150{\sim}160^{\circ}C$ taking into account the performance of device and adhesion time. Also, considering the cutting speed and safety, it is appropriate to adopt a straight blade having a clean plan at a minimum angle of $30^{\circ}$. In addition, the manufacturing capacity of the developed equipment was 3300 pots per hour.

• Korean Journal of Environmental Agriculture
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• v.33 no.3
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• pp.220-230
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• 2014

BACKGROUND: Excessive metals in the soil have become one of the most significant environmental problems. Phytoremediation has received considerable attention as a method for restoring the contaminated soils. The microbes having remarkable metal tolerance and plant growth-promoting abilities could also play a significant role in remediation of metal-contaminated soils, because bioaugmentation with such microbes could promote phytoextraction of metals. Therefore, the present study was focused on evaluating the phytoextraction of heavy metals (Co, Pb and Zn) in Helianthus annuus (sunflower) induced by bioaugmentation of a phosphate solubilizing bacterium. METHODS AND RESULTS: A phosphate solubilizing bacterium was isolated from metal-contaminated soils based on the greater halo size (>3 mm) with solid NBRIP agar medium containing 10 g glucose, 5 g $Ca_3(PO_4)_2$, 5 g $MgCl_2{\cdot}6H_2O$, 0.25 g $MgSO_4.7H_2O$, 0.2 g KCl, 0.1 g $(NH_4)_2SO_4$ in 1 L distilled water. Isolated bacterial strain was assessed for their resistance to heavy metals; $CoCl_2.6H_2O$, $2PbCO_3.Pb(OH)_2$, and $ZnCl_2$ at various concentrations ranging from $100-400{\mu}g/mL$ (Co, Pb and Zn) using the agar dilution method. A pot experiment was conducted with aqueous solutions of different heavy metals (Co, Pb and Zn) to assess the effect of bacterial strain on growth and metal uptake by Helianthus annuus (sunflower). The impact of bacterial inoculation on the mobility of metals in soil was investigated under laboratory conditions with 50 mL scaled polypropylene centrifuge tubes. The metal contents in the filtrate of plant extracts were determined using an atomic absorption spectrophotometer (Perkinelmer, Aanalyst 800, USA). CONCLUSION: Inoculation with Enterobacter ludwigii PSB 28 resulted in increased shoot and root biomass and enhanced accumulation of Co, Pb and Zn in Helianthus annuus plants. The strain was found to be capable of promoting metal translocation from the roots to the shoots of H. annuus. Therefore, Enterobacter ludwigii PSB 28 could be identified as an effective promoter of phytoextraction of Co, Pb and Zn from metal-contaminated soils.

• Horticultural Science & Technology
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• v.32 no.6
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• pp.906-911
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• 2014

A new coreopsis cultivar, 'Uridream Pink', was developed by mutation breeding using gamma-ray irradiation. Rooted cuttings of 'Uridream 01', developed at Uriseed Company, were exposed to various gray ranges of gamma-rays from a $^{60}CO$ source for 24 h in 2009 at the Korea Atomic Energy Research Institute. Using gamma-rays with the range of 10-100 Gy, a chimeric mutant with pastel pink flowers was induced at 30 Gy from 'Uridream 01', which blooms red-purple flowers (Red-purple group, 59A). Clones that produced flowers with modified pink color were separated from the chimeric mutant and fixed by more than three rounds of cutting back from 2009 to 2010. The separated mutant clones with modified pink color were found to bloom flowers with marketable color and be free of any abnormal plant characteristics. The typical color of the flowers was pastel pink (Red-purple group, 67B), and the clones were registered as 'Uridream Pink' at the Korea Seed and Variety Service (plant variety protection number: 4410). Although the size of flowers and leaves of 'Uridream Pink' are smaller than those of 'Uridream 01', the number of flowers per plant is greater. 'Uridream Pink' can be used as both a pot and a garden plant because of its long blooming period from late spring to late autumn.