• Transactions of Materials Processing
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• v.30 no.6
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• pp.301-305
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• 2021

The role of Nb addition in the tension and corrosion responses of ferrite-based stainless-steel sheets processed by cold-rolling and annealing treatment at 1173 °K was studied to evaluate the possibility for commercialization. For this purpose, the grain sizes in the samples with and without Nb content were controlled to be reasonably identical by utilizing different heat treatments within the specific range for 60 seconds. The corrosion properties of both samples were evaluated based on the analysis of polarization curves. Room-temperature tension testing showed that the strength of the sample with Nb was much higher than that without Nb whereas the elongation of the sample with Nb was slightly lower than that without Nb. The polarization curves revealed that the addition of Nb contributed to the significant improvement in protective capabilities. We thought that such combinational behavior was mainly due to the formation of niobium carbides found in the ferritic matrix.

• Corrosion Science and Technology
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• v.20 no.5
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• pp.295-307
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• 2021

Effects of ε-carbide (Fe_2.4C) on corrosion and hydrogen diffusion behaviors of ultra-strong steel sheets for automotive application were investigated using a number of experimental and analytical methods. Results of this study showed that the type of iron carbide precipitated during tempering treatments conducted at below A₁ temperatures had a significant influence on corrosion kinetics. Compared to a steel sample with cementite (Fe₃C), a steel sample with ε-carbide (Fe_2.4C) showed higher corrosion resistance during a long-term exposure to a neutral aqueous solution. In addition, the diffusion kinetics of hydrogen atoms formed by electrochemical corrosion reactions in the steel matrix with ε-carbide were slower than the steel matrix with cementite because of a comparatively higher binding energy of hydrogen with ε-carbide. These results suggest that designing steels with fine ε-carbide distributed uniformly throughout the matrix can be an effective technical strategy to ensure high resistance to hydrogen embrittlement induced by aqueous corrosion.

• Entomological Research
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• v.48 no.5
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• pp.400-404
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• 2018

In this study, we investigated resistance to the organophosphates chlorpyrifos in Tunisian populations of Culex pipiens pipiens. Three field populations were collected from Northern and central Tunisia between 2003 and 2005 and used for the bioassays tests. Our results registered moderate and high levels of resistance to chlorpyrifos which ranged from 33.8 to 111. The chlorpyrifos resistant populations were highly resistant to propoxur indicated an insensitive acetylcholinesterase 1 (AChE 1). The highest frequency of AChE 1 resistant phenotypes (64%) was recorded in the most resistant population (sample # 1). Bioassays conducted in the presence of synergists showed that not esterases were involved as the resistance mechanism to chlorpyrifos. However, CYP450 was partly involved in the resistance of the most resistant sample (# 1). Starch electrophoresis showed that three esterases were present in studied samples: A2-B2, A4-B4 and B12. Results are discussed in relation to the selection pressure caused by insecticide treatments.

• Asian-Australasian Journal of Animal Sciences
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• v.18 no.10
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• pp.1435-1439
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• 2005

Bacterio-mineral water (BMW) produced from manure has been known to exert a number of positive effects on animal production and odor control. An experiment was conducted to examine the effects of BMW produced from bio-reacted swine manure on in vitro gas production, cellulose degradation, microbial growth and fibrolytic enzyme activities of mixed rumen microorganisms. The five levels of 0, 0.001, 0.005, 0.01 and 1.0% BMW were supplemented into serum vials containing mixed rumen microorganisms. Incubations were carried out anaerobically at $39^{\circ}C$ without shaking for 0, 12, 24, 48, 72 and 96 h. There were no significant (p>0.05) differences among the treatments for the initial rate of gas production. At 72 h incubation, the gas production tended (p<0.1) to be increased by the 0.01 and 1.0% BMW treatments compared with control and the 0.001% BMW treatment. At the end of incubation (96 h), the sample supplemented with 0.01% BMW was higher (p<0.05) than control (0% BMW) in the gas production. The microbial growth rate was increased by all the BMW treatments, while 0.01% BMW was most effective in stimulating the growth rate. Although the addition of BMW on the filter paper DM degradation was not significantly influenced throughout the incubation period except the 48 h incubation, DM degradation tended to be increased by all BMW treatments compared with control. The addition of both 0.005 and 0.01% BMW highly increased (p<0.05) CMCase activity compared with control after 24 h and 48 h incubation, while at the 72 h incubation the 0.01% BMW addition only significantly increased (p<0.05). After 72 h incubation, the xylanase activity was significantly (p<0.05) increased with the addition of 1.0% BMW compared with the addition of 0.001 and 0.005% BMW, while at the other incubation times, the xylanase activity was not different among the treatments. In conclusion, the 0.01% BMW of supplementation level would be the suitable addition level to stimulate rumen fermentation increasing microbial growth and cellulose degradation.

• Food Science of Animal Resources
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• v.22 no.1
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• pp.8-12
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• 2002

This study was conducted to investigate the influence of dietary sardine oil on storage and processing characteristics in meat sample of chicken meat. Broilers were randomly assigned to one of four dietary treatments: 1) Control(commercial feed) 2) T1(commercial feed supplemented with 1% sardine oil) 3) T2(commercial feed with 2% sardine oil) and 4) T3(commercial feed with 4% sardine oil). They were fed one of the experimental diets for five weeks and slaughtered. After that, the meat samples were vacuum packaged and stored at 4$\pm$1$\^{C}$. The storage and processing characteristics were analyzed for meat samples stored over a period of 0, 1, 3, 7 and 10 days. The pH of all treatments significantly increased during the storage periods (p<0.05). The TBARS(thiobarbituric acid reactive substances) af all treatments were significantly increased as storage period extended (p<0.05). After 1 days, the TBARS of treatment groups were significantly higher than that of the control (p<0.05). The T3 showed the highest TBARS among all treatments (p<0.05). The VBN(volatile basic nitrogen) of all treatments significantly increased during storage period (p<0.05). However, the VBN was not significantly different between control and treatment groups. The WHC(water holding capacity) and heating loss were significantly increased in both control and treatment groups during storage (p<0.05) and however, WHC was not significantly different among 3 treatment. The heating loss tended to increase in treatment groups compared to the control.

• Food Science of Animal Resources
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• v.22 no.1
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• pp.37-43
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• 2002

This study was conducted to investigate the influence of dietary activated carbon(0.9%) and sardine oil (0, 1, 2, 4%) on volatile basic nitrogen(VBN), thiobarbituric acid reactive substance(TBARS), and fatty acid in meat sample of chicken. Broilers were randomly assigned to one of the file dietary treatments: 1) Control(commercial feed) 2) T1(commercial feed supplemented with 0.9% activated carbon) 3) T2(commercial feed with 0.9% activated carbon and 1% sardine oil) 4) T3(commercial feed with 0.9% activated carbon and 2% sardine oil) 4) T4(commercial feed with 0.9% activated carbon and 4% sardine oil). They were fed one of the experimental diets for five weeks and slaughtered. After that, the meat samples were stored over a period of 0, 1, 3, 7 and 10 days at 4${\pm}$1$^{\circ}C$. The VBN of all treatments significantly increased during the storage periods(p<0.05). Also, the VBN was not significantly between control and treatment group. In VBN of breast was higher compared with that of thigh. The TBARS of all treatments were significantly increased as storage period extended (p<0.05). The TBARS of control and thigh tended to be higher than that of treatments and breast. Oleic acid, palmitic acid, linoleic acid, stearic acid were major fatty acid in chicken meat. Saturated fatty acid decreased and unsaturated fatty acid increased of all treatments during storage. Oleic acid, EPA, DHA contents was higher in treatment group than the control.

• Journal of Food Hygiene and Safety
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• v.31 no.6
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• pp.406-413
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• 2016

This study was performed to evaluate and establish a sample preparation method for the detection of food-borne pathogens in animal origin foods. Ham, yogurt, and Korean beef inoculated with Escherichia coli O157:H7, Staphylococcus aureus, and Salmonella Typhimurium, were tested for the effects of diluent composition, processing time, and proportion of diluent to sample. The diluents used were peptone water (PW), Saline solution (SS), Butterfield's phosphate buffered dilution water (BPD), and Buffered peptone water (BPW). The processing time periods considered for the samples were 30, 60, 90, 120, and 300 sec, and the proportions of diluent to samples tested were 1:2, 1:4, 1:9, and 1:19. Yogurt and beef showed the highest number of bacteria when treated with BPW (p < 0.05). However, ham showed no significant difference between the treatments with four different diluents. Optimum proportions of diluent to ham, yogurt, and beef were 1:9, 1:2, and 1:4, respectively. The processing time of 120 sec was chosen as optimum, because it showed the best recovery rate in all sample types. In this manner, detection of food-borne bacteria with the selected optimal conditions was indicated by a recovery rate of more than 85%. These data suggest that an appropriate diluent composition and diluent volume should be used depending on the type of sample, which would thereby increase the accuracy of detecting food-borne bacteria in animal origin foods.

• Journal of Nutrition and Health
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• v.8 no.4
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• pp.33-37
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• 1975

This investigation was designed to determine the influence of drying methods on the free amino acids and free sugars in red pepper and to study the browning mechanism of brown-colored red pepper. Three different drying methods were employed: 1) Sun-drying at $25{\sim}28^{\circ}C$ for 15 days, 2) Drying in oven at $60^{\circ}C$ for 49 hours, and 3) Drying in oven at $90^{\circ}C$ for 8 hours. Dried and ground peels were used for the analysis of free amino acids and free sugars. The results were as follows; 1. Sixteen kinds of amino acids i.e. asparagine, methionine, and cystine etc. were identified. Total amino acid content of the sun-dried sample was not different from that of the fresh sample, but the samples dried at $60^{\circ}C$ and $90^{\circ}C$ in the oven were decreased to 24.9% and 67.4% respectively. Of amino acids identified, methionine, lysine and aspartic acid were decreased in all treatments. Especially, methionine ana aspartic acid were decreased rapidly to 71.8% and 73.3% , respectively. 2. Three kinds of free sugars i.e. glucose, fructose and sucrose were identified. The total content of free sugars was significantly decreased in each treatment. Among the reducing sugars, glucose was rapidly decreased; 65.9% for the glucose of sample dried at $90^{\circ}C$ in the oven. 3. At the higher drying temperature, the darker red color was found. Brown-color appeared at $90^{\circ}C-drying$ showed appreciable losses in carotenoid content, but the major color seems to be due to the large increase in browning compounds. 4. It was assumed that increased browning compounds of red pepper were due to the Maillard reaction which is a nonenzymatic browning process.

• Asian-Australasian Journal of Animal Sciences
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• v.16 no.12
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• pp.1755-1762
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• 2003

Two experiments were conducted to determine effects of particle size in total mixed ration (TMR) on performance of lactating cows. Three rumen cannulated Holstein cows were used in a $3{\times}3$ Latin square design for the metabolic experiment. The particle size of the diets was determined using the Penn State Particle Size Separator (PSPSS) and weighing the proportion of sample remaining on the top screen (19 mm diameter). The 3 treatments were short, medium or long diets (4.9, 24.2 and 27.8% of sample remaining on the top screen of the PSPSS, respectively). Nine farms in the Edmonton area were surveyed and the farms were placed into groups based on the particle size of the ration fed. The groups were short ${\leq}6%$, medium 7-12% and long ${\geq}13%$ of sample weight remaining on the top screen of the PSPSS. Dry matter intake was greater (p=0.07) for the medium diet than the long diet in the metabolic study and resulted in a higher (p=0.07) efficiency of milk production. On the commercial farms, a significantly (p=0.002) lower milk fat percentage was observed for the long diet compared to the short diet. The results of these studies confirm that forage particle size influences milk composition and milk fat was negatively correlated to TMR particle size.

• Journal of Soil and Groundwater Environment
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• v.15 no.6
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• pp.72-80
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• 2010

Possibility of the usage of sludge generated in coal mine drainage treatments as a briquette additive was investigated by the combination of industrial, elemental, and combustion experiments. A series of briquettes having 2% and 6% of sludge were used for the experiments. Compared to the control sample, our results show that all experimental values for the briquettes are very similar. In particular, it is worthy to note that there is no obvious difference in calorific values for the briquettes containing 2% or 6% of sludge. The calorific values are 4,250~4,360 kcal/kg, 4,240~4,250 kcal/kg, 4,180~4,210 kcal/kg, and 4,270~4,360 kcal/kg for the control sample, briquette containing 6% of Hambaek sludge, briquette containing 6% of Hamtae sludge, and briquette containing 2% of Hambaek sludge, respectively. Results of ash fusion temperature show that the temperature is greater than $1,550^{\circ}C$ for the control sample. However, the temperature for the briquettes with 6% of Hambaek sludge and 2% of Hambaek or Hamtae sludge is $1,510^{\circ}C$. For a briquette containing 6% of Hamtae sludge, the temperature of ash fusion is $1,530^{\circ}C$. After combustion, environmental impacts of the briquettes with sludge were tested. Little environmental influence was observed for the combusted briquettes with sludge.