• KOREAN JOURNAL OF CROP SCIENCE
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• v.37 no.3
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• pp.237-243
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• 1992

To determine effects of simulated acid rain on the growth and yield of rice, soybean and sesame, and on the soil acidity, two cultivars of rice, soybean and sesame were exposed twice a week to one of four simulated rain acidities[pH 2. 6, 3. 6, 4. 6 and 5. 6(control)]. The plants were protected from ambient rain by a polyethylene film cover. No visible damage due to the simulated acid rain was observed at any stage of growth for either of the crops. In rice, heading date, plant height and yield components except ripening ratio were not significantly affected by the pH ofsimulated rain, but the ripening ratio and rough rice yield linearly decreased as the pH of simulated rain was decreased. In soybean, maturing date and yield components except 100 seed weight were not significantly influenced by the pH of simulated rain, but the 100 seed weight and yield linearly decreased as the pH of simulated rain was decreased. Seed yield and the other agronomic characteristics of sesame were not significantly affected by the pH of simulated rain. Soil pH after cropping rice, soybean and sesame decreased as pH of simulated rain was decreased.

• Journal of Environmental Health Sciences
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• v.30 no.2
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• pp.149-153
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• 2004

The influences of pH on hydrogen production were also investigated over the pH range from 4.1 to 8.0 at HRT 10 hours. The hydrogen content for the produced gas was changed from 41 to 71% with corresponding pHs throughout this experiment. The produced hydrogen/carbon dioxide ratio was not vary significantly up to 6.0, then steepenly increased with increases in the pH. The maximal hydrogen yield was found to be 3.16 $\ell$/g sucrose at pH 5.0. Acetate production yield increased with increased pH, but butyrate production yield decreased with increased pH. Biomass yield increased with increased pH.

• The Korean Journal of Mycology
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• v.11 no.1
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• pp.1-7
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• 1983

Nutritional characteristics and conditions for mycelial yield of Pleurotus ostreatus and Auricularia auricula-judae in shaking culture were investigated. Among the sugar substances, glucose and mannitol showed the good effect for mycelial yield of P. ostreatus, and mannitol and fructose were good for the mycelial yield of A. auricula-judae. Among the various organic acids, fumaric acid were good for the mycelial yield of P. ostreatus and A. auricula-judae. Among the nitrogen sources, peptone and urea showed the good result for mycelial yield of P. ostreatus, and peptone and casamino acid were good for mycelial yield of A. auricula-judae. Among the various amino acids, asparagin and threonine showed the good result for mycelial yield of P. ostreatus, and serine and threonine were good for mycelial yield of A. auricula-judae. Among the various vitamins, folic acid and thiamine were suitable for mycelial yield of P. ostreatus, and folic acid, inositol and riboflavin were suitable for mycelial yield of A. auricula-judae. Mycelial yield of P. ostreatus and A. auricula-judae were enhanced by the addition of $MgSO_4\;and\;KH_2PO_4$ at the concentration of 0.08 and 0.2% respectively. The optimum temperature and pH for mycelial yield were from $25\;to\;30^{\circ}C$ and pH 5.5 to 6.5 in P. ostreatus, and from $25\;to\;30^{\circ}C$ and pH 6.0 to 7.0 in A. auricula-judae.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.33 no.1
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• pp.12-22
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• 1988

The effects of pH and Aluminum treatment on the seedling growth were examined with 11 cultivar under three levels of pH in nutri-culture.. Growth and yield responses of soil pH and nitrogen fertilization were also studied with five cultivars under 3 levels of soil pH and 3 levels of nitrogen application in the field experiment. The effect of pH on the seedling growth was not significant, but Aluminum treatment significantly decreased the seedling growth in nutri-culture except Dusan ＃12. Chlorophyll contents of leaves, dry weight of plants, culm length, spike numbers per unit area, grain numbers per spike, grain weight, and yield were decreased as the decrease of soil pH, and thus highly significant correlation between soil pH during barley growth and yield was observed in all cultivars examined. The stable cultivars to different soil pH with high yield was not found although the decreases of yield were different with cultivars. The increase of nitrogen fertilization significantly increased the nitrogen and chlorophyll contents of leaves, and dry weight of plants, while showed a little effects on the culm length, spike number per unit area, grain number per spike, grain weight and yield. The yield was significantly correlated with culm length, dry weight of plants, grain numbers per spike and 1000 grain weight at each pH levels.

• 한국생물공학회:학술대회논문집
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• 2003.10a
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• pp.422-427
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• 2003

Rhodopseudomonas palustris P4 can produce $H_2$ either from CO by water-gas shift reaction or from various sugars by anaerobic fermentation. Fermentative $H_2$ production by P4 is fast, but its yield is relatively low due to the formation of various organic acids. In order to increase $H_2$ production yield from glucose, P4 was investigated for the photo-fermentation of acetate which is a major by-product of fermentative $H_2$ production. Experiments were performed in batch modes using both light-grown and dark-grown cells. When the dark-grown P4 was challenged with light and acetate, $H_2$ was produced with the consumption of acetate after a lag period of 25 h. $H_2$ production was inhibited when a nitrogen source, especially ammonium, is present. When the dark-fermentation broth containing acetate was adopted for photo-fermentation with light-grown cells, $H_2$ production and concomitant acetate consumption occurred without a lag period. The $H_2$ yield was estimated as 2.4 - 2.8 mol $H_2/mol$ acetate and the specific $H_2$ production rate was as 9.8 ml $H_2/g$ cell${\cdot}$h, The fact that a single strain can perform both dark- and light-fermentation gives a great advantage in process development Compared to a one-step dark-fermentation, the combined dark- and light-fermentation can increase the $H_2$ production yield on glucose by two-fold.

• Transactions of the Korean hydrogen and new energy society
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• v.25 no.4
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• pp.337-343
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• 2014

This study was conducted to evaluate the characteristics of dark fermentative $H_2$ production from microalgae (Chlorella vulgaris) using batch reactors under mesophilic (25, $35^{\circ}C$) and thermophilic (45, $55^{\circ}C$) conditions. The $H_2$ yield and $H_2$ production rate increased with increasing temperature. The maximum $H_2$ yield and $H_2$ production rate were 56.77 mL $H_2/g$ dcw, 3.33 mL $H_2/g\;dcw{\cdot}h$ at $55^{\circ}C$, respectively. The activation energy calculated using Arrhenius equation was 36.24 kcal/mol, which was higher than that of dark $H_2$ fermentation of glucose by anaerobic mixed culture. Although the concentration of butyrate was maintained, the concentrations of lactate and acetate increased with increasing temperature. The $H_2$ yield was linearly proportional to acetate/ butyrate ratio.

• 한국신재생에너지학회:학술대회논문집
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• 2007.11a
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• pp.89-92
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• 2007

Partail oxidation(POX) of n-butane was investigated in this research by employing ceria-promoted Ni/calcium hydroxyapatite catalysts ($Ce_xNi_{2.5}Ca_{10}(OH)_2(PO_4)_6$ ; x = $0.1{\sim}0.3$) which had recently been reported to exhibit good catalytic performance in POX of methane and propane. The experiments were carried out with changing ceria content, $O_2/n-C_4H_{10}$ ratio and temperature. As the $O_2/n-C_4H_{10}$ feed ratio increased up to 2.75, n-$C_4H_{10}$ conversion and $H_2$ yield increased and the selectivity of methane and other hydrocarbons decreased. But with $O_2/n-C_4H_{10}$ = 3.0, $n-C_4H_{10}$ conversion and $H_2$ yield decreased. This is considered due to that too much oxygen may inhibit the reduction of Ni or induce the oxidation of Ni, which results in poor catalytic activity. The optimum $O_2/n-C_4H_{10}$ ratio lay between 2.50 and 2.75. $Ce_{0.1}Ni_{2.5}Ca_{10}(OH)_2(PO_4)_6$ showed the highest $n-C_4H_{10}$ conversion and $H-2$ yield on the whole. In durability tests, higher hydrogen yield and better catalyst stability were obtained with the $O_2/n-C_4H_{10}$ ratio of 2.75 than with the ratio of 2.5.

• The Korean Journal of Mycology
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• v.15 no.2
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• pp.108-115
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• 1987

Nutritional characteristics and cultural conditions for trehalose synthesis and mycelial yield of Pleurotus sajor-caju and Pleurotus ostreatus 201 in submerged culture were investigated. The results were as follows: Among the carbon sources, glucose was most excellent for trehalose synthesis and mycelial yield. The optimal concentration of glucose was 1%. Among the nitrogen sources, peptone was most excellent for trehalose synthesis and mycelial yield. The optimal concentration of peptone was 0.05%. The optimal concentration of $KH_2PO_4$ and $MgSO_47H_2O$ for trehalose synthesis and mycelial yield was 0.1%,0.04% and 0.2%,0.04-0.08%, respective­ly. The optimal temperature and pH for trehalose synthesis were $25^{\circ}C$ and pH 5.5. but optimal temperature and pH for mycelial yield were $30^{\circ}C$ and pH 5.5. The maximum yield of trehalose was obtanined after 10 day cultivation.

• Applied Biological Chemistry
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• v.1
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• pp.43-47
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• 1960

1). By means of the F.H. Allene and James Allenes method of the ${\alpha}-methylindole$ synthesis, 2-methylindole was prepared with the Acetyl-o-toluidine and $NaNH_2$. yield; 88%, mp. $56.5{\sim}57^{\circ}C$. 2). 23.7 gr of 3-(-Nitro-1-phenylethyl)-2-melthylindole was prepared with 0.1 mol. of the 2-methylindole and 0.1 mol. of the ${\beta}-Nitrostyrene$. yield: 84.6%, mp. $104{\sim}105^{\circ}C$. 3). Analytical results. Calcd. for $C_{17}H_{16}N_2O_2$: C, 72.84; H, 5.63; N, 9.99. Found: C, 72.62; H, 5.63; N, 9.79.

• Transactions of the Korean hydrogen and new energy society
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• v.25 no.5
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• pp.468-474
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• 2014

This study was conducted to evaluate the characteristics of mesophilic fermentative $H_2$ production from food waste which was treated by food waste disposer. It was found that $H_2$ yield and lag phase were affected by particle size of food waste. The $H_2$ yield decreased with increasing particle size while lag phase increased. The maximum $H_2$ yield was found $0.584{\pm}0.03$ mol $H_2$/mol hexose at particle size smaller than 0.30 mm. The $H_2$ production rate was also affected by chemical composition of food waste. The $H_2$ production rate linearly decreased with increasing proteins to carbohydrates ratio(P/C ratio) where the maximum value was $0.031{\pm}0.006$ mol $H_2$/mol hexose h at 0.17.