• Microbiology and Biotechnology Letters
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• v.17 no.6
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• pp.629-633
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• 1989

In the continuous reactor, the hydrogen production rate and residual glucose concentration were increased with increase of input glucose concentration, dilution rate, and recycle rate. The maximum production rate was 91 mL/Lㆍh at dilution rate 0.4/h, input glucose concentration 5.4g/L, and recycle rate 70/h in this experimental range.

• KSBB Journal
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• v.4 no.2
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• pp.185-190
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• 1989

Semicontinuous alcohol fermentation of Jerusalem Artichoke by K. fragilis CBS 1555 was performed to investigate the effect of the effective dilution rate and influent sugar concentration to the ethanol concentration and alcohol productivity at steady state. When the time interval for the replacement of fresh influent with fermentation broth was less than or equal to 1 hr, the effective dilution rate was found out to be equal to the specific growth rate. Wash out was not occurred until the effective dilution rate, 0.425 hr-1, and the maximum alcohol productivity was around 5.5 g/1·hr. In this case, the effective dilution rate was 0.25 hr-1 and the influent sugar concentration was distributed from 85 g/l to 135 g/1.

• Animal Bioscience
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• v.37 no.2
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• pp.203-209
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• 2024

Objective: This study aimed to assess the impact of the dilution ratio of Tris diluent, storage at 0℃, and long-distance transportation on the spermatozoa of Simmental cattle. It also validated the feasibility of the regional distribution of fresh semen. Methods: In experiment 1, semen was diluted at four dilution ratios (1:6, 1:9, 1:12, and 1:15) to determine the optimal dilution ratio of Tris diluent. In experiment 2, we assessed sperm viability, progressive motility (objectively assessed by computer-assisted sperm analyzer), and acrosome intactness in Tris dilutions kept at constant 0℃ for 1, 3, 6, 9, and 12 days. We compared them to Tianshan livestock dilutions (Commercial diluent). In experiment 3, semen was diluted using Tris diluent, and sperm quality was measured before and after long-distance transport. Artificial insemination of 177 Simmental heifers compared to 156 using Tianshan Livestock dilution. Results: The outcomes demonstrated that 1:9 was the ideal Tris diluent dilution ratio. The sperm viability, Progressive Motility, and acrosome integrity of both Tris and Tianshan dilutions preserved at 0℃ gradually decreased over time. sperm viability was above 50% for both dilutions on d 9, with a flat rate of decline. The decrease in acrosome integrity rate was faster for Tianshan livestock dilutions than for Tris dilutions when stored at 0℃ for 1 to 6 days. There was no significant difference (p>0.05) in sperm viability between semen preserved in Tris diluent after long-distance transportation and semen preserved in resting condition. The conception rates for Tris dilution and Tianshan livestock dilution were 49.15% and 46.15% respectively, with no significant difference (p>0.05). Conclusion: This shows that Tris diluent is a good long-term protectant. It has been observed that fresh semen can be successfully preserved for long-distance transport when stored under 0℃ conditions. Additionally, it is feasible to distribute semen regionally.

• Journal of the Korean Society of Tobacco Science
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• v.23 no.2
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• pp.179-184
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• 2001

This study was conducted to determine the smoke component distribution and the relationship between chemical components and physical characteristics of cigarettes. 16 different cigarette brands which were sold in the market were selected for this study. Five kinds of smoke components which have been tar, nicotine, water, carbon monoxide(CO) puff No., and six kinds of physical characteristics which were filter type, leaf weight, filter weight, UPD, EPD, dilution rate were analyzed. The average values in tar, nicotine, water, CO concentration were 6.5 mg/cig. 0.66 mg/cig, 1.12 mg/cig. and 6.32 mg/cig., respectively. The average ratios of nicotine/tar and CO/tar were 0.10, and 1.02 respectively. The distribution of smoke components collected in the cambridge filter and cigarette filter was different. The averages of tar and nicotine removal efficiency by a cigarette filter were 53%, and 48%, respectively. All smoking components were positively correlated with other smoking components. filter types, EPD, and dilution rate were showed high correlation to the changes of smoke components. Especially, dilution rate of cigarette strongly affected on the changes of all smoke components.

• 한국생물공학회:학술대회논문집
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• 2000.11a
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• pp.346-349
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• 2000

In order to investigate the characteristics for RNA accumulation, continuous cultures of S. cerevisiae MTY62 under the carbon-limitation or carbon-phosphate-limitation were performed. In the carbon-limited chemostat, the highest RNA content of 144 mg-RNA/g-dry cell was observed at the dilution rate of $0.30\;hr^{-1}$. In the carbon and phosphate-limited chemostat, the culture condition with the dilution rate of $0.25\;hr^{-1}$ gave the maximal RNA content of 209 mg-RNA/g-dry cell. The accumulation rate of RNA $(mg-RNA/L\;{\cdot}\;hr)$ was decreased at higher dilution rate in the carbon and phosphate-limited chemostat.

• Journal of Microbiology and Biotechnology
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• v.19 no.11
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• pp.1369-1373
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• 2009

Succinic acid was produced by continuous fermentation of Actinobacillus succinogenes sp. 130Z in an external membrane cell recycle reactor to improve viable cell concentration and productivity. Using this system, cell concentration increased to 16.4 g/l at the dilution rate $0.2\;h^{-1}$, up to 3 times higher than that of batch culture, and the volumetric productivity of succinic acid increased up to 6.63 g/l/h at the dilution rate $0.5\;h^{-1}$, 5 times higher than that of batch fermentation. However, in the continuous culture using a high dilution rate, operational problems including severe membrane fouling and contamination by lactic acid producer were observed. Another succinic acid producer, Mannheimia succiniciproducens MBEL55E, was also utilized in this system, and the cell concentration and productivity of succinic acid at the dilution rate of $0.3\;h^{-1}$ were found to be above 3 and 2.3 times higher, respectively, compared with those obtained at the dilution rate of $0.1\;h^{-1}$. These observations give a deep insight into the process design for a continuous succinic acid production by microorganisms.

• Journal of Environmental Science International
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• v.12 no.12
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• pp.1309-1313
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• 2003

This study was carried out to obtain the optimal ammonia removal efficiency using pyroligenous liquid for the economical and environment-friendly odor removal at a petty livestock farmhouse. The ammonia removal efficiencies were evaluated due to changing dilution rates(${\times}$10, ${\times}$20, ${\times}$30, ${\times}$50 and ${\times}$100 times) and different spray amounts(10$m\ell$ and 20$m\ell$) of pyroligenous liquid. The wet scrubber device was used to remove odor in closed-type livestock farmhouse. According to dilution rate of the pyroligenous liquid, the optimum rate was 20 times and the removal efficiency increased by decreasing dilution rates. In the case of spray amounts with the optimum dilution, the amount was 20 me and the removal efficiency increased by increasing spray amount. Also, the removal efficiency by using wet deodorizing device was 83.0-97.0％ with 20 times diluted liquid.

• Journal of Microbiology and Biotechnology
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• v.2 no.4
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• pp.284-287
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• 1992

Repeated-batch and continuous cultures of Lactococcus sp. 1112-1 were carried out for bacteriocin production using a glucose-casein medium. Repeated-batch culture did not efficiently enhanced the bacteriocin production. Continuous production was possible at the dilution rate of 0.4 $h^{-1}$. Maximum specific production rate ($Q^p$), bacteriocin production and biomass at the dilution rate were 347, 136 IU/g/h, 2, 121 IU/ml and 2.45 g/L, respectively.

• Journal of Korean Biological Nursing Science
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• v.12 no.2
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• pp.73-80
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• 2010

Purpose: We tested the inhibitory effect of six purchasable alcohol hand rubs against Staphylococcus aureus. Methods: Five alcohol hand rubs were collected with random manner on the market and 1 alcohol hand rubs which is currently used in a hospital was included. we designed the experimental scheme on the basis of M7-A6 method of NCCLS. Each hand rubs were diluted to 1:1, 1:10, 1:100, 1:1,000 with tryptic soy broth. S. aureus was cultured. Turbidity and the colony counting was measured. Results: With dilution rate of 1:1, all products showed more than 95% of the inhibitory effect on bacterial growth. At 1:10 dilution, product $N^{\circ}1$, 2, 3, 4, and 5 displayed the inhibitory effect of 97.77%, 92.38%, 78.19%, 97.42%, and 96.6%, respectively. But, the inhibitory effect of product $N^{\circ}6$ has been disappeared at that dilution. Over 1:100 dilution, all products lost their inhibitory effect except product $N^{\circ}5$. Product $N^{\circ}5$ displayed more than 96% of inhibitory effect at all dilution rate, even at 1:100 and 1:1,000. Conclusion: We identified that inhibitory effect on bacterial growth of alcohol hand rubs was variable. We suggest that concentration of alcohol should be checked before choosing alcohol hand rubs. Further evaluation of in vivo study is needed.

• Journal of Welding and Joining
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• v.31 no.4
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• pp.13-16
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• 2013

In this research, laser cladding characteristics were investigated for various filler metal feeding methods such as powder, cold wire, and hot wire feeding. Appropriate parameter window, deposition rate, material efficiency and dilution for each filler feeding method were evaluated with same laser power and cladding speed range. Laser powder cladding has wider process parameter window but higher material efficiency and lower dilution were achieved by laser wire cladding. Among these feeding methods, laser hot-wire cladding showed best efficiency in material usage and deposition rate.