• Korean Journal of Human Ecology
• /
• v.3 no.1
• /
• pp.88-99
• /
• 2000

This study was perfomed to search for how properties of the starch viscosity appear in different qualities, when acetic acid is added. For this study, corn starch which belongs to A-type. Potato starch to B-type. and sweet potato starch to C-type were chosen as an experimental material. which was added to acetic acid controlled as pH 4.0, 4.5, and 5.0 at the time of before and after heating. After that, the viscosity properties of each starch was analyzed using Amylogram and Brookfield viscometer. As a result. the viscosity was shown high in an order of potato. sweet potato, and corn starch. According to addition of acetic acid. tile viscosity appeared to be low. The viscosity differences of before and after heating when the acid is added were shown as follows : Amylogram shows that the lower the pH is. the lower the viscosity is when the acid is added before-heating. In case the acid is added before-heating, gelatinization temperature, consistency and setback was increased. but breakdown decreased. In case the acid is added after-heating, the viscosity goes down at soon as it is added meanwhile consistency and setback was decreased. but breakdown increased. Such properties of the viscosity show a conspicuous variation in an order of potato. sweet Potato. and corn starch. Brookrield viscometer shows that the lower the apparent viscosity is. the lower pH is at the time of before-heating when the acid is added. In case of after-heating, when the acid is added. the apparent viscosity shows a higher inclination than that of before-heating in corn starch and sweet potato starch.

• Asian-Australasian Journal of Animal Sciences
• /
• v.17 no.1
• /
• pp.94-101
• /
• 2004

The gross composition, gross amino acid content, apparent ileal amino acid digestibility and apparent ileal digestible amino acid content from 64 commercially produced meat and bone meals were statistically analysed. The samples were produced by 22 plants over a 2.5 year period with eight plants using batch dry rendering and 14 plants using low temperature rendering. A linear model with method and time of year (period) as fixed effects, plant within method as a random effect and sheep percent as a covariate was fitted to the composition data. The majority of the variation in the gross composition, amino acid digestibility and digestible amino acid content was explained by differences between plants using the same method. Neither rendering season nor origin of the raw materials contributed significantly to the observed variation in meat and bone meal protein quality. Rendering method (low temperature or batch rendering) had a significant effect on the variation observed in gross fat content, gross energy content, pepsin nitrogen digestibility, protein solubility and total lanthionine content. The digestibility of a number of amino acids and the apparent digestible content of arginine, cysteine, aspartic acid, proline and hydroxyproline were also significantly affected by rendering method. On average, batch dry and low temperature rendering systems produce meat and bone meals of similar nutritional quality. The variation between plant and within plant, however, is large, indicating that purchasing meat and bone meal from the same plant does not guarantee a consistent quality.

• Journal of Digital Convergence
• /
• v.20 no.2
• /
• pp.317-323
• /
• 2022

This study aimed to qualitative analyze the cusp variation pattern of the mandibular second premolars using a three-dimensional virtual models, and to analyze the left-right bilateral symmetry with a quantitative analysis of the tooth surface area according to the cusp variation. 127 virtual mandibular second premolars were prepared and individual absolute/relative cusp area, total crown area and groove form were analyzed using RapidForm2004(INUS technology INC, Seoul, Korea). Independent t-test, Kruskal-Wallis test and chi-square were performed. As a result, the groove form showed high bilateral symmetry between the left and right sides. Based on the left side of groove form, the bilateral symmetry was 100.0% for the U pattern, and 73.7% for the H patterned, and 78.9% for the Y pattern(p<.001). The finding could be as a meaningful reference for manufacturing CAD/CAM dental prostheses, and it is expected that further studies will be conducted on more samples including the mandibular second premolar immediately after eruption.

• Journal of the Korean Ceramic Society
• /
• v.26 no.1
• /
• pp.73-80
• /
• 1989

Preparation and characteristics of electroless Ni-P and Ni-B systems for semiconducting ceramics have been investigated as a function of deposit rate, reducing agent and pH variation. The effect of DMAB as ruducing agent is greater than that of sodium hypophosphite. The nickel electrode prepared from the nickel-phosphorus system with sodium hypophosphite shows low contact resistance of 0.99ohm compared with the resistance of 10chm in the electrode prepared from the nickel-boron system with DMAB. The contact resistance increases with increasing pH valuein the nickel-phosphorus system with sodium hypophosphite. The ratio of Ni to P is about 76.0/24.0 for the contact resistance of 0.99ohm in the above system.

• Journal of the Korean institute of surface engineering
• /
• v.24 no.4
• /
• pp.206-214
• /
• 1991

In the basic study of selective electroless Ni plating of Si wafers, plating rate and physical properties are investigated to obtain optimum conditions of contact hole filling. Si wafers are excellently activated in the concentration of 0.5M IF, 1mM PdCl2, 2mM EDTA at $70^{\circ}C$, 90sec. The optimum condition of Ni-B deposition on p-type Si wafers is 0.1M NiSO4, 0.11M Citrate, $70^{\circ}C$, pH6.8, 8mM DMAB. The main factor in the sheet resistences variation of films is amorphous and on heat treating matrix was transformed into a stable phase (Ni+Ni3B) at $300-400^{\circ}C$. But pH or DMAB concentration in the plating solution doesn't play role of heat-affected phase change.

• Journal of Animal Science and Technology
• /
• v.45 no.5
• /
• pp.703-710
• /
• 2003

The purpose of this study was to detect association between genetic variation and economic trait in the porcine heart type fatty acid-binding protein gene as a candidate gene for the traits related with growth and meat quality in pigs. The H-FABP is a 15-kDa protein expressed in several tissues with high demand for fat metabolism such as cardiac and skeletal muscle and lactating mammary gland. H-FABP is small intracellular protein involved in fatty acid transport from the plasma membrane to the site of $\beta$-oxidation and/or triacylglycerol or phospholipid synthesis. In this study, H-FABP PCR-RFLP was performed in F$_2$ population composed of 214 individuals from an intercross between Korean Native Boars and Landrace sows. PCR products from two primer sets within H-FABP gene were amplified in 850bp and 700bp. Digestion of PCR products with the restriction digestion enzymes HaeⅢ and HinfⅠ, revealed fragment length polymorphisms(RFLPs). The genotype frequencies from H-FABP/HaeⅢ was .29 for genotype DD, .53 for genotype Dd, and .15 for genotype dd, respectively. The genotype frequencies of HH, Hh, and hh from H-FABP/HinfⅠ was .38, .41 and .20, respectively, in the population. Relationships between their genotypes and economic traits were estimated. In H-FABP/HaeⅢ locus, there were specific genotypes(Dd and dd) associated with economic traits such as body weights at 3, 5, 12, and 30 week of age (p〈.05 to .001). The ‘d’ allele was associated with gaining of body weight. In H-FABP/HinfⅠ locus, Genotypes of HH and Hh associated with growth traits such as body weights at 5, 12, and 30 week of age (p〈.05 or p〈.001) and back fat thickness, body fat including abdominal and trimmed fat (p〈.001) and intramuscular fat(p〈.05) The ‘H’ allele was positively associated with gaining of body weight and fatness deposition. In conclusion, a significant association of the H-FABP gene from its genetic variation was found on body weight, intramuscular fat and backfat thickness.

• Journal of Forest and Environmental Science
• /
• v.39 no.1
• /
• pp.13-19
• /
• 2023

We investigated Soil respiration in Bluepine forest of western Bhutan, in relation to soil temperature, moisture content and soil pH and it was aimed at establishing variability in space and time. The Bluepine forest thrives in the typical shallow dry valleys in the inter-montane Bhutan Himalaya, which is formed by ascending wind from the valley bottom, which carries moisture from the river away to the mountain ridges. Stratified random sampling was applied and the study site was classified into top, mid, low slope and further randomized sample of n=20 from 30 m×30 m from each altitude. The overall soil respiration mean for the forest was found 2248.17 CO₂ g yr^-1 and it is ~613.58 C g yr^-1. The RS from three sites showed a marginal variation amongst sites, lower slope (2,309 m) was 4.64 μ mol m^-2 s^-1, mid slope (2,631 m) was 6.78 μ mol m^-2 s^-1 and top slope (3,027 m) was 6.33 μ mol m^-2 s^-1 and mean of 5.92 μ mol m^-2 s^-1, SE=0.25 for the forest. Temporal distribution and variations were observed more pronounced than in the space variation. Soil respiration was found highest during March and lowest in September. Soil temperature had almost inverse trend against soil respiration and dropped a low in February and peak in July. The moisture in the soil changed across months with precipitation and pH remained almost consistent across the period. The soil respiration and soil temperature had significant relationship R²=-0.61, p=0.027 and other variables were found insignificant. Similar relationship are reported for dry season in a tropical forest soil respiration. Soil temperature was found to have most pronounced effect on the soil respiration of the forest under study.

• Asian-Australasian Journal of Animal Sciences
• /
• v.18 no.1
• /
• pp.13-16
• /
• 2005

This study was performed to detect genetic variation of the heart fatty acid-binding protein (H-FABP) gene by PCRRFLPs approach and its association with intramuscular fat (IMF) content. Data from 223 individuals, including one Chinese native pig breed and four western pig breeds, were analyzed. The results showed that for the H-FABP gene, there was one polymorphic HinfI site in the 5'-upstream region, whereas there were one HaeIII and one HinfI (marked as $HinfI^*$) polymorphic site in the second intron, respectively. The three PCR-RFLPs were present in all breeds tested. The allele frequencies, however, revealed significant differences between them (p<0.05). Furthermore, the allele frequency distribution of HinfI in the Laiwu Black and that of $HinfI^*$ in the Hampshire breed were at disequilibrium, which might be the result of selective breeding. Results also indicated that for HinfI, HaeIII and $HinfI^*$ HFABP RFLP, significant (p<0.05) contrasts of 0.78%, -0.69% and 0.72% were detected in the least square means of IMF content between the homozygous genotype HH and hh, DD and dd, BB and bb classes, respectively. It implied that the HHddBB genotype had the highest IMF content in this experimental population and these H-FABP RFLPs could serve, to some extent, as genetic markers for use in improvement of IMF content.

• Journal of Microbiology
• /
• v.44 no.6
• /
• pp.600-606
• /
• 2006

Spore forming actinobacteria (sporoactinobacteria) isolated from soils with an acidic pH in Pinus thunbergii forests and coal mine waste were subjected to taxonomic characterization. For the isolation of acidophilic actinobacteria, acidified starch casein agar (pH adjusted to 4-5) was used. The numbers of actinobacteria growing in acidic media were between $3.2{\times}10^4$ and $8.0{\times}10^6$ CFU/g soil. Forty three acidophilic actinobacterial strains were isolated and their 16S rDNA sequences were determined. The isolates were divided into eight distinctive phylogenetic clusters within the variation encompassed by the family Streptomycetaceae. Four clusters among them were assigned to the genus Streptacidiphilus, whereas the remaining four were assigned to Streptomyces. The clusters belonging to either Streptomyces or Streptacidiphilus did not form a monophyletic clade. The growth pH profiles indicated that the representative isolates grew best between pH 5 and 6. It is evident from this study that acidity has played a critical role in the differentiation of the family Streptomycetaceae, and also that different mechanisms might have resulted in the evolution of two groups, Streptacidiphilus (strict acidophiles) and neutrotolerant acidophilic Streptomyces. The effect of geographic separation was clearly seen among the Streptacidiphilus isolates, which may be a key factor in speciation of the genus.

• Economic and Environmental Geology
• /
• v.28 no.3
• /
• pp.213-220
• /
• 1995

Geochemistry of stream water and sediment collected in the vicinity of the Donghae coal mine in the Samchuk coalfied were investigated in order to evaluate the environmental impacts of acid mine drainage. The pH of stream water ranges from 2.85(at 2 km away from the mine) to 7.92(at uncontaminated tributary). The main cation and anion species in the upper stream are $Ca^{2+}$ and $SO_{4}{^2-}$, respectively. The level of pH and the amount of $HCO^{3-}$ in stream water increase to the downstream and where uncontaminated small tributaries are joining, and in the area covered with limestone. From the results of thermodynamic calculation, the main forms of iron in stream water are estimated as $Fe^{2+}$ and $FeSO_{4}{^0}$, and most of them could be precipitated as FeO(OH) with increase of pH. The white precipitates in stream sediments particularly found around the coal mine are proved to be $Al(OH)_3$ by XRD and XRF analysis. As a result of investigation for seasonal variation of AMD, the level of pH decreased and conductivity increased in dry season.