• Macromolecular Research
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• 제13권4호
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• pp.339-343
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• 2005

Microbial hydrogel was prepared by ${\gamma}-irradiation$ of poly(${\gamma}-glutamic acid$) (PGA) which was produced from Bacillus subtilis BS 62 and it's physico-chemical characteristic was examined. The hydrogel, prepared from 10% PGA with the dose of 48 kGy, was swollen up to 1,370 times of specific water content as dry weight basis. The hydrogels obtained above the dose of 48 kGy appeared to have higher compressive strength but lower specific water content. The period to reach a swelling equilibrium for the hydrogel in deionized water at the temperature range of 4 to $45^{\circ}C$ was about 10 h. The swollen hydrogel was shrunk in ionic solutions with the increase of ionic strength, and the rate of shrinkage was greater in calcium chloride solution than in sodium chloride. Specific water content of the hydrogel was quickly decreased at $80^{\circ}C$, showing a thennally hydrodegradable property.

• 한국임상수의학회지
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• 제23권3호
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• pp.272-278
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• 2006

This study was carried out to determine therapeutic the effect of ozonated water therapy on bovine pododermatitis. In addition, bactericidal effect of ozonated water on etiological agent of bovine pododermatitis was examined. The pathohistological examination for the pododermatitis, according to application with ozonated water and ozone ointment was investigated. Thirty healthy cattle were divided two groups(each of 15) : control group(povidone group), treatment group(ozone solution group). Various parameters were evaluated in terms of the lameness score, swelling score, lesion score, WBC count, neutrophil count, pathohistological finding, and antimicrobial action. The decrease of lameness and lesion score were shown in hoof lesions on 14 days after application of ozonated water. Significant decrease of swelling was shown in hoof lesions on 14 days 1Corresponding author after application of ozonated water(p<0.01). In hematological findings, WBC count revealed values within normal range. The number of neutrophils was slightly higher than that of normal, however, this was improved on 14 days after application of ozonated water. In pathohistological findings, recovery was rapid macroscopically and microscopically in the treatment with ozonated water on the hoof lesions and ozonated water was effective. In antimicobial action, bactericidal effect was observed in treatment with ozonated water on the hoof lesions and ozonated water was effective.

• 한국식품조리과학회지
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• 제7권4호
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• pp.71-86
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• 1991

This study was attempted to enhance nutritional value of cooked rice by adding milk in cooking water. Cooked and soaked rice with five different levels of milk in cooking water (0%, A: 30%, B: 50%, C: 70%, D: 100%, E) was tested for rheological parameters, fine structural changes, sensory evaluation. 1. Water absorbance of raw rice in cooking water with varying amountes of milk, was tested at $5^{\circ}C$ and $15^{\circ}C$ for 2 hours. Water absorption ratio was decreased as milk content was increased and soaking temperature was low. Time for maximum water absorption of sample A was 40 min at 1$15^{\circ}C$ but for sample B to D, it was not reached until 120 min. 2. Electronmicroscopic observation revealed that starch granules of rice lost their regular forms by soaking for 90 minutes, but recovered most of initial regularity after 24 hours. Increase in milk content of soaking water decreased marginal sharpness of the starch granule, presumably due to reduced swelling of the granule. 3. Degree of gelatinization of cooked rice was highest in sample A and progressively decreased as milk content was increased. It was, however, increased in all samples when the cooking water to rice ratio was raised from 160% to 180%. During 4 hour storage, rates of retrogradation were not different between A and B samples, but those of C, D and E were about 2.5 times higher than A and B under the optimal condition of 170% cooking water to rice ratio. This was in the order reverse to hardness order of AC>A, D＞E at cooking water to rice ratios of 160% and 170%, above which A sample surpassed the rest of samples. 4. Sensory evaluation conducted by fifteen university students as panelists showed that there were more significant differences among five samples in flavour, texture than appearance and a notable preference for b and C over A, D and E.

• Clinical and Experimental Pediatrics
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• 제49권5호
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• pp.463-469
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• 2006

Sodium is the major cation of the extracellular fluid and the primary determinant of extracellular osmolality. Therefore, hypernatremia causes water movement out of cells, while hyponatremia causes water movement into cells, resulting in cellular shrinkage and cellular swelling, respectively. Serious central nervous system symptoms may complicate both conditions. Since hypernatremia and hyponatremia are accompanied by abnormalities in water balance, it is essential to understand the mechanisms regulating extracellular osmolality and volume as well as the pathophysiology of hypernatremia and hyponatremia, in order to manage both conditions with swiftness and safety.

• Applied Biological Chemistry
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• 제33권3호
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• pp.203-208
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• 1990

대두의 주요품질중 텍스쳐, 보수력, 색 및 Sag값 등 물리적 특성을 국내에서 재배되는 14가지의 콩 품종에 대해여 비교하였다. 텍스쳐는 rheometer로 측정하였으며 보수력은 여과지 흡수방법으로 측정하였다. 그 결과 두부의 보수력은 밀양-21호, 단엽콩, 황금콩이 높았고, 수원-138호, 수원-141호, 수원-142호는 낮았다. Sag값은 모두(-)값을 보여 성형시 가해졌던 압력을 제거하였을 때 두부가 부풀었음을 알 수 있었고 부풀음 정도는 수원-l38호로 제조한 두부가 가장 높았고, 수원-142호의 두부가 낮았다. 두부의 견고성은 품종별로 큰 차이가 있어 일반적으로 두부의 수분함량이 견고성에 영향을 주었으나 유의적인 관계는 없었다. 가장 단단한 두부는 수원-133호와 장엽이었고 가장 연한 두부는 팔당과 수원-142호이었다. 탄력성과 응집성은 수원-138호 이외에는 큰 차이가 없었으며 그 외의 관능적, 텍스쳐 성질인 부서짐성, 부착성, 검성은 품종간의 차이가 많았다.

• Journal of the Korean Wood Science and Technology
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• 제41권6호
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• pp.528-534
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• 2013

본 연구는 톱밥과 귤박을 이용하여 혼합보드를 제조하여 기본 물성을 조사하였다. 혼합보드의 귤박 혼합율이 10%에서 40%로 증가함에 따라 흡수율은 94.1%에서 86.5%로, 두께 팽창율은 27.2%에서 18.0%로, 휨강도는 $65.1kgf/cm^2$에서 $39.2kgf/cm^2$로, 경도는 $195.3kgf/cm^2$에서 $180.3kgf/cm^2$로 감소하였다. 혼합보드의 밀도가 $0.4g/cm^3$에서 $0.8g/cm^3$로 증가함에 따라 흡수율은 149.2%에서 58.6%로 감소하였으나, 두께 팽창율은 6.4%에서 17.9%로, 휨강도는 $4.2kgf/cm^2$에서 $96.6kgf/cm^2$로, 경도는 $40.4kgf/cm^2$에서 $196.2kgf/cm^2$로 증가하였다.

• 한국잠사곤충학회지
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• 제16권1호
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• pp.21-48
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• 1974

본 연구는 fibroin을 피복하여 견섬유의 경막적 성질을 지배하는 sericin에 대한 일연의 연구를 수행하여 다음과 같은 결론을 얻었다. I. Sericin Fraction의 물리화학적 특성에 관한 실험 1) 난용성 sericin은 역용성 sericin에 비하여 polar side chain을 가진 amino산(Tyr, Ser)은 적은 반면 alanine과 leucine 등의 수화성이 적은 amino산이 측정되었다. 2) 수화성의 amine산은 견사의 외층부에서, 그리고 수화성이 적은 amino산은 fibroin에 가까운 부위에 많이 존재하였다. 3) 용수에 대한 sericin의 팽윤, 용해성은 alnino산 조성만으로 해석하기는 곤란하며 sericin의 결정구조나 이차구조와의 복합구조로 변화한다고 생각된다. 4) 견사의 간섭은 환상에 가까우나 정연처리로서 소멸하였다. 5) 작잠견 sericin은 가잠견 sericin과 차이가 있었는데 자오선상에 강한 환상 Ring이 많았다. 6) Mosher 법으로 분별한 A와 B fraction 사이의 amino산 조성에는 차이가 없었다. 7) Sericin I, II, III의 X-선도에 있어서는 큰 차이는 인정되지 않으나 측쇄간격에 해당 하는 Ring에서 차이가 인정되었다. 8) 분자량 150이상의 amino산(Cys, Tyr, Phe, His,Arg)은 6N-HCl, 60분의 가수분해로서 정양되지 않았다. 9) 4.6$\AA$의 X-선 간섭은 습열과 ether 및 alcohol로 처리하므로서 소멸하는 경향이었다. 10) sericin의 가수분해물(6N-HCl)은 자오선상에 간섭 Ring(2$\AA$)을 출현시켰다. 11) 가수분해 sericin 잔사는 어느 특정한 amino산의 peptide로 추정된다. 12) Seriein III의 분해온도는 Sericin I과 II보다 높았다. 13) 견층 부위별 sericin의 D.T.A 곡선에 었어서, 내층의 sercin은 15$0^{\circ}C$와 245$^{\circ}C$에서 흡열 peak가 나타나고 외, 중층의 것보다 고온측에 이동하였다. 14) IR-spectrum에 의한 sericin fraction(Sericin I, II, III, 외층, 중층 및 내층의 sercin)의 적외선흡수 결과는 일치하였다. II. 제사공정에서의 Sericin의 팽윤, 용해특성에 관한 실험 1) 3,000 R.P.M으로 침지처리된 견층의 자유성수분은 15분간으로 탈수가 가능하고 이 경우의 원심력은 13$\times$$10^4$dyne/g 이었다. 2) sericin에 대한 Folin시약의 발색에 필요한 시간은 실온에서 30분이었다. 3) 가시광선중 측정가능파장은 500~750m$\mu$이다. 4) 실제 비색정량의 경우 정도가 높은 측정치를 얻기 위해서는, 저농도(10$\mu\textrm{g}$/$m\ell$)인 때는 650m$\mu$에서 그 이상의 농도에서늘 500m$\mu$으로 측정해야 했다. 5) sericin과 egg albumin의 파장별 흡광도곡선형은 일치하나 흡광도는 sericin이 높았다. 6) 비색분석법에 의하여 측정된 sericin의 량은 Kjeldahl 법에 비해 적은 값을 나타냈다. 7) 견층의 팽윤, 용해도에 영향하는 처리조건으로서는 온도와 시간으로서 시간보다도 온도의 방과가 켰다. 8) 팽윤, 용해도를 촉진하는 처리온도와 시간과의 관계는 저온(7$0^{\circ}C$)에서는 시간의 증가에 따라서 팽윤, 용해도는 서서히 증대하나 고온에 있어서는 단시간의 처리로 현저히 증대했다. 9) 생견의 건조온도가 높아지면 견층의 팽윤, 용해도는 반대로 감소했다. 10) 견층의 두께가 크게 되면 일정시간에 있어서의 팽윤, 용해성은 저하하였다. 11) 견층부위별 팽윤, 용해성은 외>중>내층의 순이고 품종에 따라서는 견층부위별로 차이가 있었다. 12) 견층의 납물질제거처리를 하게 되면 sericin의 팽윤, 용해성은 대조구에 비해 감소하였다. 13) 음 ion 활성제는(pH 6.0 부근) sericin의 팽윤, 용해도를 촉진시켰다. 14) 양 ion 활성제는 위와 같은 조건에서 sericin 의 흡착현상을 나타내었다. 15) 경도성분(Ca, Mg)의 농도가 증가하면, 용수의 pH는 발성방향으로 이동하였다. 16) 용수중의 경도성분과 sericin과는 서로 완충작용을 나타내었다. 17) Ca와 Mg의 경도성분이 sericin의 팽윤, 용해에 미치는 영향을 비교하면 Ca 성분이 팽윤, 용해를 억제하였 다. 18) 용수중의 경도성분의 용존은 전기전도도를 증가시켰다.

• 한국환경보건학회지
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• 제17권2호
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• pp.102-113
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• 1991

This study aimed to find out the effect of freeze-drying leek against cadmium poisoning on the cholesterol and enzyme activities in serum and superoxide radical, SOD and catalase in liver and kidney of the male rats during the administrered period. In this experiment, male rats of Sprague-Dawley strain were used. The rats were divided into 3 groups which were fed differently either for 5 weeks or for 10 weeks:basal diet, basal diet and cadmium in water and 3 % leek added diet and cadmium in water. Cadmium was administered ad libiturn 100 ppm CdCl$_{2}$ in water. The followings are the results of this experiment. 1. Leek reduced the cholesterol and the activities of GPT increase resulted from cadmium treatment. 2. Leek reduced the rate of cadmium in liver and kidney. 3. Leek reduced the activities of SOR and catalase in liver and kidney, while it enhanced the activities of SOD. 4. Leek reduced the necrosis and swelling in liver and kidney casused by cadmium treatment. This experiment showed that leek-addition group had protective effect against cadmium poisoning and increased ALPase activities in serum. Leek alleviated GPT activities in serum and cadmium concentration, necrosis, and swelling in liver and kidney. Therefore, this experiment concluded that leek has defensive power against cadmium poisoning.

• Journal of the Korean Wood Science and Technology
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• 제48권4호
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• pp.458-471
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• 2020

Effect of pre-treatment and compression ratio on specific gravity (SG) and dimensional stability improvement of three lesser-used wood species from natural forest area of North Kalimantan Province, Indonesia had been investigated. Hot soaking at 80℃ for 3 hours within 2 and 5% of boron solution was applied as pre-treatment, while compression ratio applied was 20 and 40% from the initial thickness. Densification was conducted using hot pressing machine at 30 kg/㎠ of pressure and 160℃ of temperature for 15 minutes. Specific gravity was measured gravimetrically, while dimensional stability was evaluated through thickness swelling and water absorption as the indicator. Results show that SG of densified wood was influenced by wood species and compression ratio, but not by pre-treatment applied; while dimensional stability was influenced by wood species, compression ratio, and pre-treatment. Specific gravity and water absorption of densified wood was improved significantly. Specific gravity increased 28.86-63.03%, while water absorption decreased 12.80-15.89%. Thickness swelling of 20% densified wood was lower than that of 40% densified wood.

• Macromolecular Research
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• 제9권3호
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• pp.143-149
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• 2001

Poly(aspartic acid), PASP, is a biodegradable, water-soluble polymer and offers a biodegradable alternative to polycarboxylates and other non-degradable water-soluble polymers. PASP one of poly (amino acid)s, possesses carboxylic acid pendant group in its repeating unit, which can be used for various further modification purposes. In this study we prepared high molecular weight polysuccinimide, as the precursor polymer for PASP, by thermal polycondensation ofL-aspartic acid in the presence of phosphoric acid. The polysuccinimide was hydrolyzed with 0.1 N sodium hydroxide, and then acidified to give PASP. High water-absorbent gels were produced by thermal crosslinking of freeze-dried mixture of partially-neutralized PASP and different amount of low moi. wt. PEG-diepoxide compounds in aqueous medium. The swelling behavior of the prepared gels from different size and composition of crosslinking reagent in different media was investigated and the results were discussed. This PASP-based hydrogel materials possessing inherent biodegradability, potential non-toxicity and biocompatibility, is expected to be used as a substrate for various biomedical applications as well as a general purpose super-absorbent polymer.