• Journal of Pharmaceutical Investigation
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• v.23 no.3
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• pp.41-50
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• 1993

The iontophoretic delivery across rat skin of quaternary ammonium salts (isopropamide: ISP, pyridostigmine: PS), which are positively charged over a wide pH range, was measured ill vitro. The study showed that: (a) iontophoresis significantly enhanced delivery of ISP and PS compared to respective passive transport; (b) delivery of ISP and PS was directly proportional to the applied continuous direct current density over the range of $0-0.69\;mA/cm^2;$ (c) delivery of ISP and PS was also proportional to the drug concentration in the donor compartment over the range of $0-2{\time}l0^{-2}M:$ (d) sodium ion in the donor compartment inhibited the drug transport possibly due to decreasing the electric transference number of the drug; (e) delivery of ISP and PS increased as the pH of the donor solution increased over the pH range 2-7 suggesting permselective nature of the epidermis, and inhibition of the transference number of the drugs by hydronium ion; (f) some organic anions such as taurodeoxycholate, salicylate and benzoate which form lipophilic ion-pair complexes with ISP inhibited the delivery of ISP. The degree of inhibition by the organic anions was linearly proportional to the extraction coefficient $(K_e)$ of ISP from the partition system with each counteranion between phosphate buffer (pH 7.4) and n-octanol. For PS, however, taurodeoxycholate, but not salicylate and benzoate inhibited the iontophoretic delivery. It suggests that not only sodium ion and hydronium ion but also the counteranions which form lipophilic ion-pairs with quaternary ammonium drugs are not favorable components in formulating the donor solution of the drugs to achieve an effective iontophoretic delivery.

• Journal of the Korean Wood Science and Technology
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• v.10 no.3
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• pp.152-164
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• 1982

1. In order to make the improvement of plywood quality, this study has been made. The pretreatments applied to the veneers are as follows. a) The soaking treatment of the veneer in 30 percent methanol solution for 24 hours was applied to remove some resinous materials which may cause many stain discolouring on the face of finished plywood. b) The preservative treatment of the veneer in 2 percent malenit solution for 2 to 3 minutes was adopted to make resistance against decay and insect damages. c) The fire retardant treatment of the veneer in 40 percent ammonium phosphate solution for 2 hours was applied to give retardation effect against fire burning. 2. The results summarized in this study are as follows. a) One percent resinous materials was extracted, after the soaking of the veneers in 30 percent diluted methanol. b) No marks of the dirty stains of resinous materials on the face of the treated plywood was shown, although many quite dirty stains on the face of untreated plywood have contrary seen. c) However, the strip shear test strength of the treated plywood was not decreased. It means that there is no difference in the strength between the treated plywood and the untreated plywood. The strength values were 25.08 kg/$cm^2$ and 24.98 kg/$cm^2$, respectively. d) The strip shear test strength of plywood made of the treated veneers in 2 percent malenit solution was not decreased. e) The slight decrease of the strip shear test strength of the treated plywood made of the treated veneer in 40 percent ammonuim phosphate solution was shown. However, the remarkable difference of the fire retardation activities between the treated specimens and the untreated specimens has seen as in Table 10, that is, the fire proofed specimens had taken about 28 seconds to start to burn, while the untreated specimens had taken 15 seconds to reach to burning. This means that the fire retardation effect of the fire proofed plywood was greater than that of the unproofed plywood.

• 한국생물공학회:학술대회논문집
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• 2005.04a
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• pp.124-128
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• 2005

This studies were carried out to investigate optimal conditions for Lactic acid bacteria growth, which was grown in a batch fermenter. The optimal temperature was $30^{\circ}C$, optimal pH was 6.5 and agitation speed was 100rpm and didn't supply the air. Used media compositions were yeast extract 5g/L, peptone 10g/L, sugar 20g/L, beef extract 10g/L, tween 80 1ml/L, ammonium citrate 2g/L, sodium acetate 5g/L, magnesium sulfate 0.1g/L, manganese sulfate 0.05g/L, dipotassium phosphate 2g/L. These results would be useful for enhancing lactic acid bacteria concentration.

• Biotechnology and Bioprocess Engineering:BBE
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• v.10 no.6
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• pp.546-551
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• 2005

[ ${\beta}-1,3-Glucan$ ] (curdlan) is a water-insoluble polysaccharide composed exclusively of ${\beta}-1,3\;linked$ glucose residues. Extracellular curdlan was mostly synthesized by Agrobacterium species and Alcaligenes faecalis under nitrogen-limiting conditions. In this study, we screened the microorganisms capable of producing extracellular curdlan from soil samples. For the first time, we reported Gram-positive bacterium Bacillus sp. SNC 107 capable of producing extracellular curdlan in appreciable amounts. The effect of different carbon sources on curdlan production was studied and found that the yield of curdlan was more when glucose was used as carbon source. It was also found that maximum production was achieved when the initial concentration of ammonium and phosphate in the medium was 0.5 and 1.9 g/L respectively. In this study the curdlan production was increased from 3 to 7g/L in shake flask cultures.

• The Korean Journal of Ecology
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• v.17 no.4
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• pp.425-434
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• 1994

After two highly weathered soils were treated with glucose, ammonium nitrate, monobasic potassium phosphate and biocides, and incubated for 4 or 6 weeks, adsorption tests were carried out to determine their effect on P adsorption. Glucose addition generally decreased P adsorption. The addition stimulated microbial activity, which might contribure to the reduced adsorption, probably through chelation and anion competition. Consistent endency was not observed with N treatment. Addition of P initially decreased P adsorption, probably through blockage of adsorption sites. Biocides generally decreased adsorption, probably because the microbes that 몬 been killed. Soil 1 with naturally lower levels of C and higher levels of aluminium adsorbed more P than soil 2. These results suggest that in highly weathered soils, which are low in available P and high in exchangeable Al, cultivation techniques which increase soil organic matter will also result in higher levels of plant-available P.

• Economic and Environmental Geology
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• v.38 no.6 s.175
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• pp.657-662
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• 2005

Extractions fro fertilizer and soil samples were performed to yield the operationally defined fractions 'soluble' chromate (extractable with $NH_4NO_3$), 'exchangeable' chromate (extractable with phosphate buffer pH 7.2), and these results were compared with the data obtained by extractions with ammonium sulfate, borate buffer pH 7.2, saturated borax pH 9.6, and polyphosphate (Graham's salt). In order to maintain the pH of extractant solution about constant, the concentration of extractant buffer had to be raised to at least 0.5 M. The results strongly depended on the kind of extractant, and the solid: liquid ratio. For most of the samples investigated, the extraction efficiency increased in the order borate-sulfate-nitrate-phosphate. Whereas the recovery of $K_2CrO_4\;and\;CaCrO_4$ added to the samples of basic slags prior to the extraction was about complete, the recovery of added $PbCrO_4$ was highly variable. In soil extracts, the color reaction was interfered from co-extracted humics, which react with the chromate in weak acid solution during the time period necessary for color reaction (1 hour). However, this problem can be overcome by standard addition and subtraction of the color of the extractant solution. In soil extract of about pH < 7, organic material reduced chromate during the extraction period also, and standard addition of soluble chromate is recommended to prove recovery and the stability of chromate in the samples. In admixtures of soils and basic slags, results for hexavalent chromium were lower than from the mere basic slags. This effect was more pronounced in phosphate than in nitrate extracts. As a proficiency test, samples low in organic carbon from contaminated sites in Hungary were tested. The results from $NH_4NO_3$ extracts satisfactorily matched the results of the Hungarian labs obtained from $CalCl_2$ extractants.

• Journal of the Korean Ceramic Society
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• v.43 no.4 s.287
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• pp.235-241
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• 2006

Mullite short fibers have been fabricated by adapting the Kneading-Drying-Calcination (KDC) process and characterized. The effect of the addition of foaming agent and calcination temperature on the formation of mullite fibers from coal fly ash, was examined. In the present work, ammonium alum $NH_4Al(SO_4)_2\;12H_2O$ synthesized trom coal fly ash and sodium phosphate $Na_2HPO_4\;2H_2O$ were used as foaming agents. After calcination at $1300^{\circ}C$ for 10 h and then etching with 20% HF solution at $50^{\circ}C$ for 5 h using a microwave heating source, the alumina-deficient $(AI_2O_3/SiO_2$ = 1.13, molar ratio) orthorhombic mullite fibers with a width of ${\sim}0.8mm$ (aspect ratio >30), were prepared from the coal fly ash with $AI_2O_3/SiO_2$ = 0.32, molar ratio by the addition of $NH_4AI(SO_4)_2\;12H_2O$, and with further addition of 2 wt% sodium phosphate. The excessive addition of sodium phosphate rather decreased the formation of mullite fibers, possibly due to the large amount of liquid phase prior to mullitization reaction.

• ALGAE
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• v.18 no.2
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• pp.157-167
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• 2003

Effect of the effluent of the sewage and wastewater plants on the algal growth was investigated from the 19 plants located in the Nakdong river basin. Most of the samples showed high values of the algal growth potential (AGP) when they were mixed with natural river water at 20% of final concentration. At 20% of the mixing ratio, the mixed effluents of sewage and wastewater showed 3.5 and 1.8 times higher AGP than those of the natural river water. The higher AGP values are attributable to the high contents of phosphorus and ammonium in the effluent. The mixing ratio of effluents of the discharge/river flow was highest in the Kumho River (42.8%) followed by the middle of Nakdong River (22.7%), Kam Stream (13.9%), Byungsung Stream (13.3%), Yangsan Stream (7.9%), and Young River (5.4%). Comparison of the trophic state of the effluents with natural river water indicated that the effluents showed higher trophic values than natural water. Concentrations of total phosphorus, total nitrogen and conductivity in the effluents were 12.3, 4.9 and 5.3 times higher than the those found in natural river water respectively. The AGP values were highly related with the trophicity of the water especially on the concentrations of phosphate and ammonium. Toxicities of the treated sewage water, wastewater and livestock waste water tested by the luminescent bacteria, Vibrio fischerii were generally low.

• Microbiology and Biotechnology Letters
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• v.26 no.2
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• pp.173-178
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• 1998

This study presents the influence of ammonium-nitrogen on microorganisms in swine wastewater. For the anaerobic batch fermentation, two different methods were used. One is the dilution of wastewater with water. The other method is the elimination of ammonium-nitrogen from the wastewater. By addition of MgO into wastewater, non-soluble crystall was formed under alkaline condition as MgNH$_4$PO$_4$6$H_2O$ (MAP). The master culture was adapted in swine wastewater for more than 3 months, in water-dilution method, the dilution of wastewater with 25% water gave us the best result in efficiency of COD removal. Two hundred hours later MAP-treated wastewater showed the efficiency of the COD removal more than 80%. Under same condition obtained none MAP-treated wastewater about 50%. MAP treatment carried out the very effective anaerobic digestion with swine wastewater. The important result in this study is that the low ratio of C:N influenced on anaerobic microorganisms more than high concentration of ammonium nitrogen in swine wastewater. The struvite for the crystallforming has no toxic effect on methanogenic bacteria.

• Korean Journal of Soil Science and Fertilizer
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• v.40 no.6
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• pp.482-487
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• 2007

This study was conducted to investigate the effect of long-term continuous application of fertilizers for rice cultivation. Changes of physical and chemical properties of paddy soil and the rice yield by continuous application of NPK fertilizers, ammonium sulphate, and urea over fifty years, from 1954 to 2003, were investigated. The rice yield index of each treatment were 100 of NPK plots, 84 of ammonium sulphate plots, 81 of urea plots, and 62 of no fertilizer plots. The variance of yield was large according to the quality of irrigation water. Nutrient uptakes by rice plants in ammonium sulphate and urea plots were significantly smaller than those in NPK plots; 86 and 75% in T-N, 79 and 82% in $P_2O_5$, 64 and 58% in $K_2O$, and 94 and 90% in $SiO_2$, respectively. Bulk density of soil in NPK plots significantly decreased compared to those in no fertilizer, ammonium sulphate, and urea plots, whereas CEC in NPK plots increased compared to other plots. Soil pHs of all plots were higher than that before experiment which was 5.2; 6.0 in no fertilizer, 5.9 in urea and NPK, and 5.4 in ammonium sulphate plots. The available phosphate in soil increased by $2.5mg\;kg^{-1}\;yr^{-1}$ when $70kg\;ha^{-1}$ of P fertilizer applied for rice cultivation, and decreased by $1.8mg\;kg^{-1}\;yr^{-1}$ when no P fertilizer applied.