• Journal of Microbiology and Biotechnology
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• v.3 no.1
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• pp.46-50
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• 1993

In 12:12 hour light/dark cycle cultivation of D. salina 1650, maximum specific growth rate of 0.59 (l/day) and 0.35 (g-crude hydrocarbons/l/day) were obtained. The cell growth was inhibited at above 15$\times$$10^{-4} (kcal/cm^2/h)$ of light intensity in an outdoor cultivation. It was also showed that temperature is one of the critical growth parameters in the outdoor cultivation. The hydrocarbon production from D. salina 1650 seems to be partially growth related production process, and these algal hydrocarbons can be used for subsituting petroleum directly or through cracking processes. The value of weight fraction carbon of D. salina 1650 was similar to that of Botryococcus braunii and so was the hydrocarbon productivity.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.23 no.1
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• pp.8-15
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• 2011

Cooling load reduction was analysed of a ventilation system adopting a regenerative evaporative cooler. The regenerative evaporative cooler is a kind of indirect evaporative cooler which cools the air down to its inlet dewpoint temperature in principle without change in the humidity ratio. The regenerative evaporative cooler was found able to cool the ventilation air to $18{\sim}21^{\circ}C$ when the outdoor condition ranges $25{\sim}35^{\circ}C$ and 0.01~0.02 kg/kg. When the outdoor humidity ratio is lower than 0.018 kg/kg, the regenerative evaporative cooler was found to provide cooling performance enough to compensate the ventilation load completely and to supply additional cooling as well. Energy simulation during the summer was carried out for a typical office building with the ventilation system using the regenerative evaporative cooler. The results showed that the seasonal cooling load can be reduced by about 40% by applying the regenerative evaporative cooler as a ventilation conditioner. The reduction was found to increase as the outdoor temperature increases and the outdoor humidity ratio decreases.

• The Korean Journal of Mycology
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• v.11 no.4
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• pp.177-181
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• 1983

To improve cultivation technique for the stable and high yield, the outdoor fermentation of rice straw bundles, and pasteurization and fermentation of rice straw compost in tunnel were carried out. 1) Mycelial growth of P. ostreatus was becoming rapid and dense according to prolongation of fermentation periods outdoor rice straw bundles, but days untill fully mycelial growth after spawning was short. 2) As the fermentation period of rice straw bundles was 6 days (three times turning), yield of P. ostreatus was the highest as $50.5kg/3.3m^2 and increased 24% of yield than those of conventional method. 3) When it was fermented rice straw compost in tunnel for 4 days, mycelial growth of P. ostreatus was rapid and dense, and also days untill budding after spawning, was shorter, yield $67.6kg/3.3m^2$, resulted in increasing 17% of yield than those of conventional method. 4) On being sterilization and fermentation of the rice straw compost in tunnel, the production cost was decreased 22.3% in compared with conventional method.

• The Korean Journal of Mycology
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• v.36 no.2
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• pp.163-171
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• 2008

We have surveyed the variation of physical and chemical characteristics of aerobic and anaerobic outdoor fermentation of cotton wastes using for oyster mushroom cultivation. The inner temperature of cotton wastes fermented aerobically covered with thin cloth and setting pallet at bottom was higher than that of anaerobic fermented cotton wastes covered with P.E vinyl and the maximum temperature was $75^{\circ}C$ at 5th day after fermentation. pH of cotton wastes fermented aerobically was increased up to 8.9 after fermentation of $9{\sim}12$ days, but that of anaerobically fermented was decreased up to 5.0. Total carbon content was decreased but total nitrogen content was increased when fermentation was in progress. Oxygen concentration of cotton wastes fermented aerobically was decreased until 6 days after fermentation but increased after 9 days of fermentation. Ammonia concentration of cotton wastes fermented aerobically and anaerobically was below 10 ppm and $20{\sim}85\;ppm$ respectively. In anaerobic condition the cotton wastes was contaminated with mold ($15{\sim}50%$), where no contamination was found in aerobic condition during spawn running stage. Yields of mushroom grown on cotton wastes aerobically fermented for $6{\sim}9$ days was $23.0{\sim}23.6\;kg$ per $3.3\;m^2$ area.

• Journal of Korea Technical Association of The Pulp and Paper Industry
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• v.41 no.3
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• pp.71-75
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• 2009

Cotton waste is usually used for cultivating agaric mushroom after outdoor fermentation for a few months. Electron beam was used to break down the polymer chaims of cotton waste for increasing low molecular weight soluble sugars, which may enhance the agaric mushroom cultivation. By increasing electron beam radiation, alpha cellulose content of the cotton waste was decreased while beta cellulose content and hot water solubles were increased. Electron beam radiation over 240 kGy on cotton waste caused significant increase of mushroom yield without lowering mushroom quality.

• Journal of Mushroom
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• v.16 no.4
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• pp.250-256
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• 2018

The windrow turner, widely used for outdoor fermentation of mushrooms in Europe, has been improved by using rice straw instead of wheat straw in accordance with Korea's actual situation. It was compared with conventional excavator work, and the results were as follows. Agitation performance was $81m^3/hr$, which was 2.8 times higher than $28.6m^3/hr$ of excavator. As a result of the temperature distribution in the pile at the end of the fermentation stage, it was found that the temperature at the lower part of the pile was $5^{\circ}C$ higher than that of conventional pile. This was more favorable for aerobic fermentation. Meanwhile, ash ratio of prototype ($30.9{\pm}1.1%$) was higher than that of control $28.4{\pm}1.6%$. In the case of prototype turner agitation, the yield of mushroom cultivation was $880kg/66m^2$, that was 22.9% higher than the conventional control yield of $716kg/66m^2$.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.23 no.4
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• pp.243-250
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• 2011

In order to investigate the effects of PAG oil concentration on heat transfer performance and pressure drop during gas cooling process of $CO_2$, the experiments on fin-tube heat exchanger of $CO_2$ heat pump were performed. The experimental apparatus consists of a gas cooler, a heater, a chiller, a mass flow meter, a pump and measurement system. Experiments were conducted in various experimental conditions, which were inlet temperature($110^{\circ}C$), mass flow rates (50, 55, 60, 65, 70 g/s) and PAG oil concentration(0 to 2.6 wt%). Heat transfer rate decreased with the increase of the oil concentration and the decrease of inlet pressure. And pressure drop increased with the increase of the oil concentration and mass flow rate of refrigerant. The COP reduction by deterioration of gas cooler performance with oil concentration was analyzed. When inlet pressure of gas cooler is 100 bar, the COP reduction was estimated by 6% under 1 wt% of oil concentration.

• Korean Journal of Soil Science and Fertilizer
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• v.37 no.2
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• pp.116-123
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• 2004

This study was conducted to investigate the changes in physicochemical and microbiological properties during fermenting process of organic fertilizer which was made from the mixture of organic materials such as sesame oil cake, fish meal, blood meal, rice bran, ground bone meal, and natural minerals such as illite, crusted oyster shell and loess. They were mixed and fermented for 70 days. The sesame oil cake and rice bran, major ingredients for organic fertilizers, consisted of 7.6 and 2.6% total nitrogen, 3.6 and 4.6% $P_2O_5$, 1.4 and 2.2% $K_2O$, respectively. The ground bone meal included 29.2% $P_2O_5$ and illite included 3.8% $K_2O$. Temperature of organic fertilizer during the fermentation rapidly increased over $50^{\circ}C$ within 2 days after mixing and stabilized similar to outdoor temperature after 40 days. Moisture content decreased from 36.3 to 16.0% after 1 month. C/N ratio of organic fertilizer slightly increased until 30 days and thereafter, it slowly decreased, It resulted from the faster decrease of total nitrogen concentration compared with organic matter. Concentration of $NH_4-N$ in organic fertilizer rapidly increased from 1,504 to $5,530mg\;kg^{-1}$, the highest concentration after 10 days. Meantime, $NO_3-N$ concentration was low and constant about $150mg\;kg^{-1}$ over the whole fermenting period. This result seemed to be due to the high pH. The organic ferfilizer fermented for 70 days was composed of 2.7% N, 2.8% $P_2O_5$, 1.8% $K_2O$, and 35.9% organic matter. Total populations of aerobic bacteria, Bacillus sp. and actinomycetes, after fermenting process, were $12.5{\times}10^{10}$, $45.5{\times}10^{5}$ and $13.6{\times}10^{5}cfu\;g^{-1}$ respectively. Pseudomonas sp. was $71.9{\times}10^{7}cfu\;g^{-1}$ at first, but it rapidly decreased according to the rise of temperature. Yeasts played an important role in the early stage of fermentation and molds did in the late stage.

• The Korean Journal of Mycology
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• v.7 no.1
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• pp.13-73
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• 1979

These studies were conducted to investigate nutrient sources and supplementary materials of synthetic compost media for Agaricus bisporus culture. Investigation were carried out to establish the optimum composition for compost of Agaricus bisporus methods of out-door fermentation and peakheating with rice straw as the main substrate of the media. The incidence and flora of harmful organisms in rice straw compost and their control were also studied. 1. When rice straw was used as the main substrate in synthetic compost as a carbon source. yields were remarkably high. Fermentation was more rapid than that of barley straw or wheat straw, and the total nitrogen content was high in rice straw compost. 2. Since the morphological and physico-chemical nature of Japonica and Indica types of rice straw are greatly dissimilar. there were apparent differences in the process of compost fermentation. Fermentation of Indica type straw proceeded more rapidly with a shortening the compost period, reducing the water supply, and required adding of supplementary materials for producing stable physical conditions. 3. Use of barley straw compost resulted in a smaller crop compared with rice straw. but when a 50%, barley straw and 50% rice straw mixture was used, the yield was almost the same as that using only rice straw. 4. There were extremely high positive correlations between yield of Agaricus bisporus and the total nitrogen, organic nitrogen, amino acids, amides and amino sugar nitrogen content of compost. The mycerial growth and fruit body formation were severely inhibited by ammonium nitrogen. 5. When rice straw was used as the main substrate for compost media, urea was the most suitable source of nitrogen. Poor results were obtained with calcium cyanamide and ammonium sulfate. When urea was applied three separate times, nitrogen loss during composting was decreased and the total nitrogen content of compost was increased. 6. The supplementation of organic nutrient activated compost fermentation and increased yield of Agaricus bisporus. The best sources of organic nutrients were: perilla meal, sesame meal, wheat bran and poultry manure, etc. 7. Soybean meal, tobacco powder and glutamic acid fermentation by-products which were industrial wastes, could be substituted for perilla meal, sesame meal and wheat bran as organic nutrient sources for compost media. B. When gypsum and zeolite were added to rice straw. physical deterioration of compost due to excess moisture and caramelization was observed. The Indica type of straw was more remarkable in increase of yield of Agricus bisporus by addition of supplementing materials than Japonica straw. 9. For preparing rice straw compost, the best mixture was prepared by 10% poultry manure, 5% perilla meal, 1. 2 to 1. 5% urea and 1% gypsum. At spring cropping, it was good to add rice bran to accelerate heat generation of the compost heap. 10. There was significantly high positive correlation (r=0.97) between accumulated temperature and the decomposition degree of compost during outdoor composting. The yield was highest at accumulated temperatures between 900 and $1,000^{\circ}C$. 11. Prolonging the composting period brought about an increase in decomposition degree and total nitrogen content, but a decrease in ammonium nitrogen. In the spring the suitable period of composting was 20 to 25 days. and about 15 days in autumn. For those periods, the degree of decomposition was 19 to 24%. 12. Compactness of wet compost at filling caused an increase in the residual ammonium nitrogen. methane and organic acid during peak heating. There was negative correlation between methane content and yield (r=0.76)and the same was true between volatile organic acid and yield (r=0.73). 13. In compost with a moisture content range between 69 to 80% at filling. the higher the moisture content, the lower the yield (r=0.78). This result was attributed to a reduction in the porosity of compost at filling the beds. The optimum porosity for good fermentation was between 41 and 53%. 14. Peak heating of the compost was essential for the prevention of harmful microorganisms and insect pests. and for the removal of excess ammonia. It was necessary to continue fer mentatiion for four days after peak heating. 15. Ten species of fungi which are harmful or competitive to Agaricus bisporus were identified from the rice compost, including Diehliomyces microsporus, Trichoderma sp. and Stysanus stemoites. The frequency of occurrance was notably high with serious damage to Agaricus bisporus. 16. Diehliomyces microsporus could be controlled by temperature adjustment of the growing room and by fumigating the compost and the house with Basamid and Vapam. Trichoderma was prevented by the use of Bavistin and Benomyl. 17. Four species of nematodes and five species of mites occured in compost during out-door composting. These orgnanisms could be controlled through peakheating compost for 6 hours at $60^{\circ}C$.