• Korean Journal of Plant Resources
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• v.14 no.2
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• pp.175-181
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• 2001

Dormancy of intact zoysiagrass seeds hinders its seed propagation in which presowing seed treatment must be done to overcome it. The study was done to remodel the presowing treatments of zoysiagrass seeds by determining the treatment effects of seedcoat softening, prechilling, drying and combined light treatment with them or during germination stage. Seedcoat softening with different chemicals (NaOH 20%, KOH 20%, $H_2SO_4\;8M, acetone 20%) and periods (10, 30, 60 min.), prechilling with different periods at 3$^{\circ}C$, and drying with 4 hours at 35$^{\circ}C$ was done. Light sources were also applied with 660 nm red LED light, commercial fluorescent and incandescent light and darkness. Germination test was done in alternative day and night temperature of 35 and 2$0^{\circ}C$ to check the daily germination rates. With seeds treated with NaOH 20% for 30 minutes, red and incandescent light showing similar responses inclined their germination rates compared to dark conditions. Drying resulted in its higher rate than non-drying but fluorescent light treatment forced during drying more enhanced the rate than red light. While mean germination rate considering all the seedcoat softening treatment periods was the greatest in $H_2SO_4$ in comparison with NaOH, KOH and acetone, NaOH treatment for 30 minutes showed the best rate among the all the treatment levels. In the conditions of sowing them to no-mulching field, presowing treatment procedure of zoysiagrass seeds was remodeled: the seedcoat softening treatment with NaOH 20% for 30 minutes was done, washed, and chilled at 3$^{\circ}C$ for 2 weeks before dried under 4 hour fluorescent light illumination at 35$^{\circ}C$.

• Journal of the Korean Institute of Telematics and Electronics
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• v.22 no.3
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• pp.1-5
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• 1985

CulnSe2 single crystals were grown by the Bridgman method. The n.CulnSe2 single cry seals with a carrier concentration of 2.6$\times$1016/㎤ were obtained by a thermal treatment of the grown CulnSe2 single crystals in selenium atmosphere. The solar cell of n.CulnSe2-3M KOH+3M Na2 S+4M S junction was prepared by using n.Culnsel single crystal as a photoanode, 3M KOH+SM Nat S+4M S as Polysulfide solutions. The FF of the solar cell was 0.44 under 100 mW/cml illumination condition, and the conversion efficiency was 5.67%.

• Ocean Science Journal
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• v.42 no.4
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• pp.223-230
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• 2007

To understand the origin and biogeochemistry of the organic matter in surface sediments of Lake Shihwa and Lake Hwaong, organic nitrogen, inorganic nitrogen, labile organic carbon, and residual organic carbon contents as well as stable isotope ratios for carbon and nitrogen were determined by KOBr-KOH treatment. Ratios of organic carbon to organic nitrogen $(C_{org}/N_{org})$ (mean = 24) were much higher than ratios of organic carbon to total nitrogen $(C_{org}/N_{tot})$ (mean= 12), indicating the presence of significant amounts of inorganic nitrogen in the surface sediments of both lakes. Stable isotope ratios for organic nitrogen were, on average, $5.2\%_{\circ}$ heavier than ratios of inorganic nitrogen in Lake Shihwa, but those same ratios were comparable in Lake Hwaong. This might be due to differences in the origin or the degree of degradation of sedimentary organic matter between the two lakes. In addition, stable isotope ratios for labile organic carbon were, on average, $1.4\%_{\circ}$ heavier than those for residual organic carbon, reflecting the preferential oxidation of $^{13}C$-enriched organic matter. The present study demonstrates that KOBr-KOH treatment of sedimentary organic matter can provide valuable information for understanding the origin and degradation state of organic matter in marine and brackish sediments. This also suggests that the ratio of $(C_{org}/N_{org})$ and stable isotope ratios for organic nitrogen can be used as indexes of the degree of degradation of organic matter.

• Textile Coloration and Finishing
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• v.4 no.3
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• pp.91-96
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• 1992

The crystalline character of NaOH and KOH-cellulose complex having different tension ratio was studied using X-ray diffraction analysis. Cellulose crystalline lattices in tension alkali treatment cotton were identified by measuring and indexing the 101, 101, and 002 reflections. According as alkali treatment tension ratio increased on, cellulose gave rise to the formation of I rather than cellulose II. It seemed that a part of the fine structure of cellulose increased orientation with antiparaell and parallel chain crystal structure. The high tension ratio alkali treatment cotton resulted in lower dye sorption and in higher breaking strength and crease recovery.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.29 no.6
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• pp.370-375
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• 2016

In this paper, we investigated the electrical properties of crystalline silicon solar cell fabricated with Ni/Cu/Ag plating. The laser process was used to ablate silicon nitride layer as well as to form the selective emitter. Phosphoric acid layer was spin-coated to prevent damage caused by laser and formed selective emitter during laser process. As a result, the contact resistance was decreased by lower sheet resistance in electrode region. Low sheet resistance was obtained by increasing laser current, but efficiency and open circuit voltage were decreased by damage on the wafer surface. KOH treatment was used to remove the laser damage on the silicon surface prior to metalization of the front electrode by Ni/Cu/Ag plating. Ni and Cu were plated for each 4 minutes and 16 minutes and very thin layer of Ag with $1{\mu}m$ thickness was plated onto Ni/Cu electrode for 30 seconds to prevent oxidation of the electrode. The silicon solar cells with KOH treatment showed the 0.2% improved efficiency compared to those without treatment.

• Journal of the Korean Ceramic Society
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• v.40 no.5
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• pp.468-474
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• 2003

Activated carbon fibers were prepared from stabilized PAN fibers by physical and chemical activation to compare their characteristics. In this study, stabilized PAN fibers were activated by physical activation with steam and CO$_2$, and by chemical activation with KOH. The fabricated activated carbon fibers were evaluated and compared such as specific surface area, pore size distribution, pore volume, and amount of iodine adsorption. In the steam activation, a specific surface area of 1635 m$^2$/g was obtained after heat treatment at 990$^{\circ}C$. Otherwise, in the CO$_2$ activation, produced activated carbon fibers had been a specific surface area of 671 m$^2$/g after heat treatment at 990$^{\circ}C$. In chemical activation using KOH, a specific surface area of 3179 m$^2$/g was obtained with a KOH/ stabilized PAN fiber ratio of 1.5 : 1 at 900$^{\circ}C$. Nitrogen adsorption isotherms for fabricated activated carbon fibers showed type I and transformation from type I and II in the Brunauer-Deming-Deming-Teller (B.D.D.T) classification. Increasing specific surface area Increased the amount of iodine adsorption in both activation methods. Because the ionic radius of iodine was smaller than the interior micropore size of activated carbon fibers.

• Food Engineering Progress
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• v.13 no.4
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• pp.262-268
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• 2009

A dark brownish pigment in the crude polysaccharide from Auricularia auricula was adsorbed by activated charcoal. The leaching of the pigment adsorbed on activated charcoal and regeneration of activated charcoal used was investigated with eight kinds of solvents. The highest leaching capacity was obtained with the alkaline solution (KOH). The optimum volume of 1 M KOH solution per activated carbon was 45 mL/g, and the treatment for 10 min during single stage leaching was sufficient to achieve the leaching equilibrium. Second-order kinetic model provided the best fitting for the pigment leaching. The pigment leaching capacity of 88.9% was obtained by seven times of treatment with 1 M KOH solution at 25$^{\circ}C$, while at 95$^{\circ}C$, leaching capacity of 82.6% was achieved with single stage alone showing the significant increase of leaching capacity with increasing temperature. The regenerated activated charcoal was nearly as effective as fresh activated charcoal in pigment adsorption of crude polysaccharide from Auricularia auricula.

• Korean Journal of Soil Science and Fertilizer
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• v.45 no.5
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• pp.810-816
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• 2012

In order to develop liquid fertilizer using rendering by-product, rates and velocities of degradation from rendering by-product using pig cadaver investigated under different amount of injection and time with degradation agents (KOH, NaOH, $HNO_3$ and $H_2SO_4$). The amount of residue by degradation agent of $HNO_3$ treatment method was higher than that in KOH, NaOH and $H_2SO_4$ treatment methods. The degradation velocities (K; $hr^{-1}$) of rendering by-product in KOH treatment method were higher in the order of 25% ($0.0309hr^{-1}$) > 30% ($0.0268hr^{-1}$) > 20% ($0.0142hr^{-1}$) > 15% ($0.0111hr^{-1}$) > 10% ($0.0102hr^{-1}$) of weight of rendering by-product. In all conditions, the degradation velocity of rendering by-product using $H_2SO_4$ 30% of weight of rendering by-product was rapid than that for KOH, NaOH and $HNO_3$ treatment methods. Degradation rates of rendering by-product using NaOH were similar to that of KOH and $H_2SO_4$ except for $HNO_3$ under injecting 25% and 30% of rendering by-product weight.

• Korean Journal of Medicinal Crop Science
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• v.4 no.2
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• pp.172-177
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• 1996

The influences of testa-removal of seed, partial cutting of embryo, xylene treatment, growth regulator, chemical treatment and low temperature treatment on the seed germination of Lycoris aurea were investigated. The germination rate of the testa-removed seeds was higher than that of the whole seeds, and the seeds treated by testa-removal+xylene was 63% of germination. $GA_3$ was more effective than kinetin treatment, and seeds treated with $GA_3$ 200ppm showed 60% of germination. $KNO_3$ was more effective than KOH treatment, and seeds treated with 0. 1% $KNO_3$ was 76% of germination. The seeds, stored for two months at $5^{\circ}C$, showed the highest germination rate with 93%

• Journal of Environmental Science International
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• v.20 no.11
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• pp.1499-1507
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• 2011

Practical disposal of transformer insulation oil laden with PCBs (polychlorinated biphenyls) by a chemical treatment has been studied in field work. The transformer insulation oil containing PCBs was treated by the required amounts of PEG (polyethylene glycol) and KOH, along with different reaction conditions such as temperatures and times. The reaction of PEG with PCBs under basic condition produces arylpolyglycols, the products of nucleophilic aromatic substitution. Removal efficiencies of PCBs in insulation oil before and after chemical treatment were examined. The removal efficiency of PCBs was very low at lower temperatures of 25 and $50^{\circ}C$. Under the reaction condition of PEG 600/KOH/$100^{\circ}C$/2hr, removal efficiency of PCBs was approximately 70%, showing completely removal of PCBs containing 7~9 chlorines on biphenyl frame which appear later than PCB IUPAC Number 183 (2,2',3,4,4',5',6-heptaCB) in retention time of GC/ECD. However, when increasing the reaction temperature and time to $150^{\circ}C$ and 4 hours, removal efficiency of PCBs reached 99.99% without any formation of PCDDS/PCDFs during the process. Such reaction conditions were verified by several official analytical institutions. In studying the reaction of PEG with PCBs, it confirmed that the process of chemical treatment led to less chlorinated PCBs through a stepwise process with the successive elimination of chlorines.