• Journal of the Korean Society of Food Science and Nutrition
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• v.41 no.4
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• pp.539-549
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• 2012

In order to acquire basic data on the development of squid processing food, we investigated changes in the composition of boiled squid upon heat treatment ($100^{\circ}C$), acid treatment (acetic acid, 0~5%), and pre-boiling ($55^{\circ}C$, $80^{\circ}C$). The proximate composition of squid was 73~78% moisture and 19~24% crude protein, treatment with acid solution had a significant effect on the proximate composition of boiled squid (p<0.05). The major free sugars were ribose and glucose in all treatment samples. The $55^{\circ}C$ pre-boiled sample had lower levels of glucose than the other samples. The total free sugar content of the non-peeled sample was the highest, followed by the $80^{\circ}C$ pre-boiled sample, whereas the sugar content in the $55^{\circ}C$ pre-boiled sample was very low. With regards to amino acid content, proline was the highest in all samples, followed by taurine and histidine. Treatment with acid solution had a significant effect on the total free amino content of boiled squid (p<0.05). The total free amino acid content of the $55^{\circ}C$ pre-boiled sample was the highest, followed by the $80^{\circ}C$ pre-boiled sample and non-peeled sample. Inosine and related compounds were not detected in any of the samples, and the adenosine triphosphate (ATP) content was low. The hypoxanthine contents of the $55^{\circ}C$ and $80^{\circ}C$ pre-boiled samples were the highest, the adenosine monophosphate (AMP) and inosine monophosphate (IMP) contents were similar, and the IMP content of the non-peeled sample was higher than those of the peeled samples. The palmitic acid content was very high and constituted 40% of total saturated fatty acids. eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) contents were also high and constituted 60% of total unsaturated fatty acids. Of these, DHA content was the highest, followed by palmitic acid and EPA, which accounted for about 85% of total fatty acids. No difference in fatty acid content was observed between acid treatment and pre-boiling. The mineral P content was the highest on average in all boiled squid samples, followed by K, Na, Mg, and Ca contents. In addition, the pre-boiling temperature and acid solution concentration had significant effects on the mineral content. Further, heavy metal, Cd, Pb, and As contents were detected only at trace amounts, and their levels were lower than standard and permissible amounts for food.

• Journal of the Korean Crystal Growth and Crystal Technology
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• v.16 no.3
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• pp.106-111
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• 2006

The objective of this paper is to compare the surface features of two kinds of nano-porous activated carbon fiber (NPACF) treated with potassium and the variation of their properties by phosphoric acid pre-treatment. X-ray diffraction (XRD) patterns indicate that NPACF containing potassium species show better performance for potassium and potassium salts by pre-treatment with phosphoric acid. In order to present the causes of the differences in surface properties and specific surface area after the samples were treated with phosphoric acid, pore structure and surface morphology are investigated by adsorption analysis and SEM. For the chemical composition microanalysis for potassium loading of the NPACF pre-treated with phosphoric acid, samples were analyzed by EDX. Finally, the type and quality of oxygen groups are determined from the method proposed by Boehm.

• Proceedings of the Korea Technical Association of the Pulp and Paper Industry Conference
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• 2006.06b
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• pp.465-469
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• 2006

Pre-treatment methods to determine various heavy metal contents in packaging papers were investigated by ICP-ES (Inductively Coupled Plasma Emission Spectrometry) analysis. Pre-treatment methods utilized in this study include dry ashing and decomposition methods ($HNO_{3-}HClO_{4-}HF,\;HNO_{3},\;and\;H_{2}SO_{4-}HNO_{3}$). They were compared with the conventional extraction (water) and migration (3% acetic acid) methods. The five representative heavy metals (Cd, As, Pb, Cr and Hg) were analyzed. For Cd, Hg, and As, the results were below detection limit of the instrument. In case of Cr and Pb, the migration test is considered to be a better method compared to the extraction test, but all pretreated methods showed much higher detection efficiency than the extraction or migration test. However, the detection ratio between the migration test and decomposition methods was different. Among all decomposition methods, the nitric acid - perchloric acid - hydrofluoric acid treatment brought a slightly higher detection value than others, but there was no significant difference among them except sulfuric acid - nitric acid method. Concerning Pb, the sulfuric acid - nitric acid method showed a low detection efficiency compared to other decomposition methods. The sulfuric acid - nitric acid method is, thus, not considered to be a suitable analysis method for Pb in packaging papers.

• The Journal of Advanced Prosthodontics
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• v.8 no.5
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• pp.339-344
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• 2016

PURPOSE. Pre-surface treatments of coping materials have been recommended to enhance the bonding to the veneering ceramic. Little is known on the effect on shear bond strength, particularly with new coping material. The aim of this study was to investigate the shear bond strength of veneering ceramic to three coping materials: i) metal alloy (MA), ii) zirconia oxide (ZO), and iii) lithium disilicate (LD) after various pre-surface treatments. MATERIALS AND METHODS. Thirty-two (n = 32) discs were prepared for each coping material. Four pre-surface treatments were prepared for each sub-group (n = 8); a) no treatment or control (C), b) sandblast (SB), c) acid etch (AE), and d) sandblast and acid etch (SBAE). Veneering ceramics were applied to all discs. Shear bond strength was measured with a universal testing machine. Data were analyzed with two-way ANOVA and Tukey's multiple comparisons tests. RESULTS. Mean shear bond strengths were obtained for MA ($19.00{\pm}6.39MPa$), ZO ($24.45{\pm}5.14MPa$) and LD ($13.62{\pm}5.12MPa$). There were statistically significant differences in types of coping material and various pre-surface treatments (P<.05). There was a significant correlation between coping materials and pre-surface treatment to the shear bond strength (P<.05). CONCLUSION. Shear bond strength of veneering ceramic to zirconia oxide was higher than metal alloy and lithium disilicate. The highest shear bond strengths were obtained in sandblast and acid etch treatment for zirconia oxide and lithium disilicate groups, and in acid etch treatment for metal alloy group.

• Journal of the Korean Society of Food Science and Nutrition
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• v.38 no.10
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• pp.1392-1396
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• 2009

Antioxidative effects of rice hull extracts pre-treatment with various organic acids were evaluated. After incubating rice hull in 50 mM of five different organic acid solutions (acetic, citric, lactic, phosphoric, and tartaric acid) for 18 hours at room temperature, hydrothermal treatment at $121^{\circ}C$ for 30 min was carried out. Antioxidant activity of the rice hull extract was evaluated by determining total phenol contents (TPC), DPPH radical scavenging activity (RSA), reducing power (RP), and ABTS RSA. Pre-treatment with 50 mM phosphoric acid significantly increased TPC, DPPH RSA, and RP, while it decreased ABTS RSA. The effect of phosphoric acid concentration was also determined. TPC and DPPH RSA of rice hull extract increased with concentration of pre-treated phosphoric acid; in contrast, RP showed the reverse pattern. The results indicated that pre-treatment of rice hull with organic acid was very effective for increasing phenolic compounds and antioxidant activity of rice hull extract.

• Journal of Korea Technical Association of The Pulp and Paper Industry
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• v.45 no.3
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• pp.27-35
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• 2013

Cotton linter pre-treatment methods using electron beam and sulfuric acid were investigated to prepare high quality regenerated fibers for fabrics. So far, NaOH was used to reduce the degree of polymerization (DP) of the cotton linter for ease of dissolving by cellulose solvent. Two pre-treatment methods were developed to reduce the consumption of the chemicals (NaOH) and to control the DP of cellulose more precisely. Changes in ${\alpha}$-cellulose contents and brightness by the pre-treatments were also important concerns. Both electron beam irradiation and sulfuric acid were shown to be effective on controlling the DP of cellulose and to reduce the chemical consumption, but reduced ${\alpha}$-cellulose contents as well in this study. Sulfuric acid pre-treatment, which needed additional washing process after the pre-treatment when comparing to the electron beam irradiation method, gave the highest brightness and the highest reduction of ${\alpha}$-cellulose content.

• 한국신재생에너지학회:학술대회논문집
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• 2006.11a
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• pp.541-543
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• 2006

The feasibility of biodiesel production from soapstock by acid catalyst was tested. The water content of soapstock was more than 40%. Before the esterification of soapstock, the pre-treatment of soapstock was conducted adding potassium hydroxide and sulfuric acid. The pre-treated soapstock contained 99.6wt% of free fatty acid. When the free fatty acid was esterified with methanol, the fatty acid methyl ester content became 91.7wt% under the solid acid catalyst, Amberlyst-15. When this biodiesel was distilled the methyl ester content was 98.1wt% which satisfied the biodiesel Standard. Amberlyst-15 could be recovered easily because it was the soliid catalyst. When sulfuric acid was used as the acid catalyst, the fatty acid methyl ester content was 91.0wt%. From the results, it was possible to produce biodiesel efficiently from soapstock after pre-treatment. Because soapstock is very cheap, it will become good feedstock for biodiesel product ion.

• Analytical Science and Technology
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• v.19 no.2
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• pp.121-130
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• 2006

In this study, silver pre-treated activated carbons are transformed using sulfuric acid. From the results of adsorption, each isotherm shows a distinct knee band, which is characteristic of microporous adsorbents with capillary condensation in micropores. In order to reveal the causes of the differences in adsorption capacity and specific surface area after the samples were washed with various strengths of sulfuric acid, surface morphology and external pore structure were investigated by SEM. X-ray diffraction patterns indicated that Ag-activated carbons show better performance for silver and silver compounds removal by post-treatment with acid. The FT-IR spectra of silver-activated carbon samples show that the acid post-treatment was consequently associated with the removal of silver with an increased surface functional group containing oxygen of the activated carbon. The type and quality of oxygen groups are determined on the method proposed by Boehm. For the chemical composition microanalysis of silver-activated carbons transformed by post-treatment with sulfuric acid, samples were analyzed by EDX.

• Korean Journal of Soil Science and Fertilizer
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• v.48 no.3
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• pp.213-217
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• 2015

Soil moisture shortage can reduce yield of waxy corn because maize is one of the sensitive crops to the drought stress. Farmers cannot irrigate due to limited water resource and irrigating facilities although applying water is the most effective practice to solve the drought problem. The study was conducted to investigate the pre-treatment effect of salicylic acid on reducing drought damage of waxy corn (Zea mays L.). Salicylic acid at concentration of 0.2 mM was applied at seven-leaf stage or ten-leaf stage three times. Drought stress was imposed by withholding irrigation from 11 days before anthesis to 10 days after anthesis. Application of salicylic acid significantly increased ear length by 11.0~12.3% and yield by 8.8~11.3% compared with non-treated control, indicating that the drought injuries of waxy corn can be alleviated through pre-treatment of salicylic acid at the vegetative stage.

• The Korean Journal of Food And Nutrition
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• v.33 no.5
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• pp.459-472
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• 2020

The purpose of this study was to evaluate the physicochemical components and antioxidant activities of wheat sprout powder prepared by the enzymatic hydrolysis and lactic acid bacteria treatment. The four kinds of pre-treatment were: no treatment (WP), treated with enzyme (WPE), treated with lactic acid bacteria (WPL), and treated with enzyme and lactic acid bacteria (WPEL) were applied to the wheat sprout powder. The WPEL had higher total free amino acid and essential amino acid content than the other samples. As for the volatile aroma of the wheat sprout powder, 29 types of compounds were identified in the WP and WPL, 28 types in the WPE, and 27 types in the WPEL, respectively. The total polyphenols and flavonoids contents, in the wheat sprout powder was enhanced with the enzyme and the lactic acid bacteria pre-treatment. The WPEL had highest DPPH radical scavenging activities. The overall acceptability was the highest at 6.24 points in the WPEL. Based on these observations, it was confirmed that the enzyme and lactic acid bacteria pre-treatment could improve the antioxidant activities and active component of the wheat sprout powder.