• Journal of Mechanical Science and Technology
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• v.14 no.2
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• pp.177-187
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• 2000

Dilution is an important factor which influences the properties of clad layer. In this paper the change of dilution during laser cladding and the control of dilution are simulated by a finite element method. The adaptive mesh method is adopted for the time-dependent finite element method computation so that the shape of melt pool can be well represented. The situation of the width control of melt pool is also simulated, which indicates that the dilution can be controlled if the width of melt pool is controlled. Computational results indicate that if a line energy (input energy per unit distance) remains constant the dilution will increase with time, especially at the beginning. Simulation results show that it is possible to control dilution in a certain range if the line energy decreases with time. Experiment of Nd: YAG laser cladding with wire feeding is performed. Experiment results coincide well with the FEM results.

• 한국연소학회:학술대회논문집
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• 2003.12a
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• pp.19-26
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• 2003

Experimental measurements of flame structure and soot characteristics were performed for ethene inverse diffusion flames (IDF). IDF has been considered as the excellent flow field to study the incipient soot because soot particle do not experience the oxidation process. In this study, LIF image clarified the reaction zone of IDF with OH signal and PAH distribution. laser light scattering technique also identified the being of soot particle. To address the degree of soot maturing, C/H ratio and morphology of soot sample were investigated. From these measurements, the effect of flow residence time and temperature on soot inception could be suggested, and more details on soot characteristic in the IDF was determined according to fuel dilution and flame condition. The fuel dilution results in a decrease of temperature and enhancement of residence time, but the critical dilution mole fraction is existed for temperature not to effect on soot growth. Also, the soot inception evolved on the specific temperature and its morphology are independent of the fuel dilution ratio of fuel.

• International Journal of Oral Biology
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• v.46 no.2
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• pp.94-97
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• 2021

The purpose of this study was to introduce a new in vitro method for evaluating the antimicrobial activity of toothpaste, reflecting the actual toothbrushing time and the dilution of toothpaste by salivation. We designed three experimental groups and one negative control group. The experimental groups were (1) 90 μL of toothpaste + 10 μL 1X phosphate-buffered saline (PBS, 9/10 dilution group), (2) 50 μL of toothpaste + 40 μL 1X PBS (1/2 dilution group), and (3) 25 μL of toothpaste + 65 μL 1X PBS (1/4 dilution group). During toothbrushing, saliva is continuously secreted into the oral cavity and the toothpaste concentration is diluted over time during toothbrushing. Therefore, the 1/2 and 1/4 dilution experimental groups were added. The negative control group was toothpaste diluted 20,000-fold with 1X PBS. Miracle Fresh Doctor toothpaste and Streptococcus mitis KCOM 1350, Prevotella intermedia KCOM 1107, Fusobacterium nucleatum subsp. polymorphum KCOM 1322, and Aggregatibacter actinomycetemcomitans KCOM 1306 were used as the toothpaste and target bacterial strains, respectively. The number of bacterial cells plated on agar plates in the negative control group was 1,000 CFU. If the number of colonies on the experimental group plate was less than one, the treatment was considered to have > 99.9% bactericidal activity. These results suggest that this new in vitro method for antimicrobial evaluation could be used as the standard method for testing the antimicrobial activity of toothpaste.

• Transactions of the Korean Society of Mechanical Engineers B
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• v.27 no.5
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• pp.596-603
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• 2003

Present study has been conducted to see the relative effects of adding N: to fuel-side and air-side on flame structure, soot formation and NOx emissions. Experiments were carried out to ascertain to what degree chemical kinetics and/or molecular transport effects can explain the differences in soot formation and NOx emission by studying laminar diffusion flames. Direct photograph was taken to see the flame structure. CARS techniques was used to get the flame temperature profiles. And spatial distribution of soot could be obtained by PLII method. CHEMKIN code was also used to estimate the global residence time to predict NOx emissions at each condition. Results from these studies indicate that fuel-side dilution is more effective than air-side dilution in view of NOx emissions. However, air-side dilution shows greater effectiveness over fuel-side dilution in soot formation. And turbulent mixing and heat transfer problems were thought to be considered in practical applications.

• Transactions of the Korean Society of Mechanical Engineers B
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• v.28 no.9
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• pp.1101-1109
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• 2004

Experimental measurements of flame structure and soot characteristics were performed fur ethene inverse diffusion flames (IDF). IDF has been considered as the excellent flow field to study the incipient soot because soot particle do not experience the oxidation process. In this study, LIF image clarified the reaction zone of IDF with OH signal and PAH distribution. laser light scattering technique also identified the being of soot particle. To address the degree of soot maturing, C/H ratio and morphology of soot sample were investigated. From these measurements, the effect of flow residence time and temperature on soot inception could be suggested, and more details on soot characteristic in the IDF was determined according to fuel dilution and flame condition. The fuel dilution results in a decrease of temperature and enhancement of residence time, but the critical dilution mole fraction is existed for temperature not to effect on soot growth. Also, the soot inception evolved on the specific temperature and its morphology are independent of the fuel dilution ratio of fuel.

• Preventive Nutrition and Food Science
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• v.13 no.4
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• pp.334-339
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• 2008

This study was designed to determine the optimum conditions of heating temperature, heating time and dilution rates for producing heated garlic juice by using central composite design of response surface methodology. Garlic 3Department of Biosystems Engineering, Chungbuk National University, Cheongju 361-763, Korea was heated using a high temperature and pressure treatment apparatus. Total soluble solid contents ranged from 4.4 at $130^{\circ}C$ 3 hr and 6 fold dilution to 5.89 at $115^{\circ}C$ for 2 hr and 8 fold dilution. The highest total acidity was 0.55% at $120^{\circ}C$ for 3 hr and 2 fold dilution. The pH ranged from 4.01 at $130^{\circ}C$, 3 hr and 6 fold dilution to 5.85 at $120^{\circ}C$, 1 hr and 6 fold dilution. From the results of statistical analysis on the sensory evaluation the predicted optimum processing conditions for best color, taste, flavor and overall acceptance were $119.41^{\circ}C$, 3.11 hr, 5.85 fold dilution, $118.23^{\circ}C$, 3.57 hr, 3.15 fold dilution, $120.54^{\circ}C$, 3.47 hr, 5.01 fold dilution and $119.54^{\circ}C$, 3.18 hr, 5.66 fold dilution, respectively. The application of response surface methodology for preparing heated garlic juice processing showed a good correlation with high significance.

• 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.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.32 no.1C
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• pp.17-25
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• 2012

CLSM (Controlled Low Strength Material) using coal ash, which has the advantages of self-leveling, self-compacting, flowability, easy re-excavation, has been developed. In this study, CLSM additionally mixed with foaming agent for structural backfill material, aimed at lightness of materials, was developed called light-weight foamed CLSM. As the basic study of this material, to determine the optimum final mixing time and dilution ratio of existing light-weight foamed CLSM, flow, slurry unit weight and unconfined compressive strength test according to each impact factor were performed at the standard mix proportion. As the results of tests, CASE N (Final mixing time 4 min, dilution ratio 2%), CASE O (Final mixing time 3 min, foam agents ratio 3%, dilution ratio 2%) were satisfied with the standard of flow test (above 20cm), slurry unit weight test (12~15 $kN/m^3$) and unconfined compressive strength test (800 kPa~1200 kPa). These results will indicate the standard optimum final mixing time and dilution ratio of light-weight foamed CLSM for structural backfill.

• Journal of the Society of Cosmetic Scientists of Korea
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• v.38 no.3
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• pp.201-207
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• 2012

The influence of different dilution procedures on the properties of oil-in-water (O/W) nano-emulsions obtained by dilution of oil-in-ethanol (O/E) microemulsions with water has been studied. The system water/ethanol/nonionic surfactant/silicone oil with ethanol was chosen as model system. The dilution procedures consisted of adding water (or microemulsion) stepwise. By mixing O/E microemulsions into water, nano-emulsions with droplet diameters of 30 nm were obtained. In contrast, by mixing water into O/E microemulsion, emulsions with diameter of 400 nm were obtained The dilution methods were shown to be a key factor determining the properties of the emulsions. There were no change in diameters of nanoemulsion droplets against time, however sizes of droplets in the emulsion with larger droplets were increased with time and the mechanism of unstability was thought to be Ostwald ripening.

• 한국연소학회:학술대회논문집
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• 2012.11a
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• pp.63-64
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• 2012

The present study has numerically investigated the effects of the fuel-side nitrogen dilution on the precise structure and NOx formation characteristics of the turbulent syngas nonpremixed flames. Numerical results indicate that for highly diluted case, the flame structure is dominantly influenced by the turbulence-chemistry interaction and marginally modified by the radiation effect. On the other hand, no-dilution case with the longer flight time and the relatively intermediate scalar dissipation rate is influenced strongly by the radiative cooling as well as moderately by the turbulence-chemistry interaction.