• 한국재료학회지
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• 제32권9호
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• pp.361-368
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• 2022

The overall process, from the pre-treatment of aluminum substrates to the eco-friendly neutral electroless Ni-P plating process, was observed, compared, and analysed. To remove the surface oxide layer on the aluminum substrate and aid Ni-P plating, a zincation process was carried out. After the second zincation treatment, it was confirmed that a mostly uniform Zn layer was formed and the surface oxide of aluminum was also removed. The Ni-P electroless plating films were formed on the secondary zincated aluminum substrate using electroless plating solutions of pH 4.5 and neutral pH 7.0, respectively, while changing the plating bath temperature. When a neutral pH7.0 electroless solution was used, the Ni-P plating layer was uniformly formed even at the plating bath temperature of 50 ℃, and the plating speed was remarkably increased as the bath temperature was increased. On the other hand, when a pH 4.5 Ni-P electroless solution was used, a Ni-P plating film was not formed at a plating bath temperature of 50 ℃, and the plating speed was very slow compared to pH 7.0, although plating speed increased with increasing bath temperature. In the P contents, the P concentration of the neutral pH 7.0 Ni-P electroless plating layer was reduced by ~ 42.3 % compared to pH 4.5. Structurally, all of the Ni-P electroless plating layers formed in the pH 4.5 solution and the neutral (pH 7.0) solution had an amorphous crystal structure, as a Ni-P compound, regardless of the plating bath temperature.

• 센서학회지
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• 제26권6호
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• pp.414-419
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• 2017

The optical characteristics of cresol red, phenol red, and neutral red immobilized in the thin film were investigated with absorbance measurement in order to find a sensing part of a fiber-optic pH sensor. Sol-Gel method with tetramethyl orthosilicate as a precursor was used to immobilize the pH indicators in the thin film. The absorbance spectra were measured when pH indicators were immobilized in the film and were dissolved in the buffer solution. Experimental results showed that the absorbance spectra could be changed when the pH indicator is immobilized in the thin film. As compared with other pH indicators, the neutral red exhibited similar absorbance spectra regardless of physical conditions and was sensitive over whole pH range between 4 and 11. In addition, the absorbance ratio of base peak to acid peak tended to increase in proportion to the increase in pH. Experimental results indicate that the neutral red is a good pH indicator for fabrication of a sensing part of the fiber-optic pH sensor.

• 생명과학회지
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• 제11권6호
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• pp.595-602
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• 2001

The prelectin histochemical methods had been applied to study mucosubstances properties of esophageal mucous cells in four teleostean species, i, e.. sebastes schlegli, Halichoeres poecilopterus, Bryzoichtys lysimus and Takifugu pardalis. The following methods were used: periodic acid Scheff"s(PAS) reaction, alcian blue(AD) pH 2.5, AB pH 1.0, AB pH 2.5-PAS, aldehyde fuchsin (AF) pH 1.7-AB pH 2.5 and high iron diamine (HID)-AD pH 2.5 stainings. The number size and shape of esophasgeal mucous cells studied depend on the fish species. Esophageal mucous cells of Sebastes schlegli and Halichoeres poecilopterus were mixed with large, medium sized and small mucous cells, but these cells of the species were mixed with medium sized and small mucous cells. The large esophageal with moderate to considerable amount of acid mucin. Most of the large mucous cells in these species contained neutral mucin and strongly sulfomucin, whereas a few mucous cells contained neutral mucin, strongly sulfomucin, and sialomucin. Medium sized and small mucous cells of these species contained considerable to large amount of neutral mucin, and small to considerable amount of acid mucin, Most of the medium sized and small mucous cells contained neutral mucin and sialomucin, but a few mucous cells contained neutral mucin and strongly sulfomucin or neutral combined with strongly sulfomucin and sialomucin. Most of the esophageal mucous cells pf Bryzoichthys lysimus contained small amount of neutral mucin, while on the other hand a feww mucous cells contained small amount of neutral mucin and minimal amount of sialomucin. But the esophageal mucous cells of Takifugu pardalis contained considerable amount of neutral mucin only.

• Journal of Life Science
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• 제10권2호
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• pp.1-8
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• 2000

This experiment was performed to study the structure of esophageal mucousa and the histochemical properties of glycosaminoglycans of esophageal mucous cells in four teleostean species, i.e., Agramus agramus, Inimicus japonicus, Epinephelus chlorostigma and Helicolenus dactylopterus. To observe the structure of eosphageal mucosa, hematoxylin-eosin(H-E) staining was used. The glycosaminoglycans was stained with PAS(periodic acid schiff), alcain blue(AB) pH 2.5, AB pH 1.0, aldehyde fuchsin(AF) pH 1.7, AF pH 1.0, AB pH 2.5-PAS, AB pH 1.0-PAS and AF pH 1.7-alcian blue pH 2.5. As for the amount and histochemical composition of glycosaminglycans in Agramus agramus, most of mucous secreting columnar cell and mucous cells contain large and moderate amount of neutral glycosaminoglycans. A few of mucous cells having small amount of neutral glycosamino-glycans and minimal amount of sulfated glycosamino-glycans. In Inimicus japonicus, the esophageal mucous cells were composed of most of medium sized and large mucous cells with moderate amount of neutral glycosaminoglycanonly only, a few of medium sized and large mucous cells and most of small mucous cells with considerable amount of neutral glycosaminoglycans and minimal to small amount of nonsulfated glycosaminoglycans, and a feq of small mucous cells with small amount of neutral glycosaminoglycans and minimal amount of sulfated glycosaminoglycans. In Epinephelus chlorostigma, most of medium sized and large mucous cells were mixed small amount of neutral glycosaminoglycans with sulfated glycosaminoglycans, a few of which were contained with moderate or considerable amount of neutral glycosaminoglycans with sulfated glycosaminoglycans, while most of small mucous cells containing considerable amount of neutral glycosaminoglycans and small to moderate or considerable to minimal amount of nonsulfated glycosaminoglycans(sialomucin) a few of which containing a mixture of considerable amount of neutral glycosaminoglycans and considerable amount of nonsulfated glycosaminoglycans(sialomucin)only. In Helicolenus dactylopterus, most of medium sized and large mucous cells, mixing with moderate to considerable amount of neutral glycosaminoglycans and small to moderate amount of sulfated glycosaminoglycans, while most of small mucous cells with considerable amount of nonsulfated glycosaminoglycans (sialomucin), a few of which having a mixture of considerable amount of neutral glycosaminoglycans and considerable or small amount of nonsulfated glycosaminoglycans(sialomucin).

• 생명과학회지
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• 제15권5호
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• pp.707-714
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• 2005

경골어류 4종(조피볼락, 용치놀래기, 송곳니베도라치 및 졸복)의 장관 상피 선조연 및 배상세포의 점액질의 조직화학적 성상을 밝히기 위해 PAS 반응, AB pH 1.0 및 pH 2.5, AB pH 2.5-PAS, AF pH 1.7-AB pH 2.5 및 HID-AB pH 2.5 염색법을 사용하였다. 장관 선조연의 점액질은 조피볼락의 근위장과 직장은 중성점액질만을, 중간장과 원위장은 중성점액질과 산성점액질의 혼합성이었으나 용치놀래기는 전 장관에서 중성점액질과 산성점액질을 함유하고 있었으며, 송곳니베도라치와 졸복의 전 장관은 중성점액질만을 함유하고 있었다. 중성점액질의 양은 조피볼락과 용치놀래기는 중등량 내지 상당량, 송곳니베도라치와 졸복은 미량 내지 소량이었다. 장 배상세포 점액질의 양과 성상은 어종 및 장 부위에 따라 차이가 있어 송곳니베도라치와 졸복은 중성점액질만을 함유하고 조피볼락과 용치놀래기는 중성 점액질, sulfomucin 및 sialomucin의 혼합성이었다. 중성점액질의 양은 졸복의 원위장 및 직장은 상당량 내지 다량이었고 조피볼락의 전장, 용치놀래기의 근위장, 원위장 및 직장, 졸복의 근위장 및 중간장은 중등량 내지 상당량이었으며 용치놀래기의 중간장은 미량 내지 소량이었다. 조피볼락의 장 배상세포는 미량의 강 sulfomucin, 약 sulfomucin 및 미량 내지 소량의 sialomucin을 함유하고 있었으며 직장을 제외한 용치놀래기의 장 배상세포는 미량 내지 소량의 강 sulfomucin과 sialomucin을 함유하고 있었다.

• 한국미생물·생명공학회지
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• 제23권1호
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• pp.31-35
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• 1995

Using the alkalophillic Bacillus sp. SH-8 and its mutant Bacillus sp. SH-8M capable of growing at the neutral pH, the amino acid compositions of the cell wall and cell membrane were studied at varying cultivation pH's. The pattem of protein electrophoresis was also tested. It was elucidated that the amino acids consisting of the cell wall were alanine, glutamic acid, lysine, aspartic acid, and meso-diaminopimelic acid. There was not any significant difference in the amino acid compositqon betweeo`two straqns regardless of the culture pH. As the results of HPLC ssay, glutamic acid and aspartic aciu accounted for more than 50% in the amqno acid composytqon of the cell wall. By the isolatqon of the crude cell membrane and the SDS-PAGE analysis, it was found that there was a considerable difference qn the protein pattern when the straqns were cultured at the neutral pH. In addition, by the two dimensional gel electrophoresis, it was confirmed that there was a difference in the protein patterns between two strains cultivated at the neutral pH medium but no difference at the alkaline medium.

• 한국농공학회논문집
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• 제49권3호
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• pp.51-60
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• 2007

This study was performed to evaluate void ratio, compressive and flexural strengths, and pH properties according to the content ratio of rice husk ash, aggregate size, and neutral treatment time of porous concrete with content of rice husk ash produced as an agricultural by-product. The SEM results for cement mortar with a 5% rice husk ash for the weight of cement formed more C-S-H hydrates due to the $SiO_2$ of rice husk ash. In the XRD test, cement mortar with a 5% rice husk ash for the weight of cement registered a higher peak point of approximately $2{\theta}=20{\sim}25^{\circ}$ compared to cement mortar without rice husk ash. According to the results of the XRD and SEM tests, the $SiO_2$ that was a major chemical element of rice husk ash generated a large amount of calcium hydroxide in the early stage of the hydration process of cement leading to the formation of ettringite. The void ratio of porous concrete with rice husk ash decreased with increasing content ratio of rice husk ash. In addition, the void ratio of porous concrete with rice husk ash decreased compared to porous concrete without rice husk ash. The compressive and flexural strength of porous concrete with a 5% and 10% content ratio of rice husk ash slightly increased compared to concrete without rice husk ash. The pH value of porous concrete rapidly decreased immediately after neutral treatment. Then, it gradually increased and decreased again after 14 days. However, the pH value was nearly the same regardless of neutral treatment time in 28 curing days. Also, for neutral treatment, the pH value of porous concrete showed appropriate pH levels (less than 9.5) in all mixtures for planting at 28 curing days.

• Archives of Pharmacal Research
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• 제20권6호
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• pp.643-646
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• 1997

Thermal stability of a red pigment, carthamin, frm Carthamus tinctorius was investigated to explore possible applications as natural color additives for foods, cosmetics, and nutraceuticals. Degree of degradation reactions of carthamin at acidic, neutral and alkaline conditions were determined with UV/V is spectral measurements. Decomposition half lives of carthamin at 25.deg. C were 4.0 h, 5.1 h, and 12.5 h at pH 5.0, pH 7.0, and pH 12.0, respectively, indicating that carthamin is much more stable at alkaline pH than acidic or neutral conditions. The activation energies of carthamin at pH 5.0, pH 7.0, and pH 12.0 were 15.6, 15.7 and 16.8 kcal/mol, respectively.

• 한국응용과학기술학회지
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• 제24권2호
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• pp.205-210
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• 2007

In this paper, we describe a study on the relationship between neutral emulsion manufacture and hardening test of films. The hardeners were prepared by condensation of equimolar amounts of trichlorotriazine with benzene- or naphthalene-based amino or oxy acids at 0 to $5^{\circ}C$ and at pH 7, and used as hardening agents for gelatin. The hardening test of neutral emulsion layers was studied at pH 7.0. For example I(R=ONa) had strong hardening properties, I substituted with an aminobenzosulfonate moiety $(R=NHC_6H_4-p-SO_3Me$ where Me = K, Na) was a much weaker gelatin hardener, and when substituted with amino- or oxynaphthalene derivative (II, III) did not harden gelatin at all. Compound with 2 dichlorotriazine groups as IV exhibited hardening properties. The hardener can be used in neutral emulsion layer of film and showed good hardening effect.

• Bulletin of the Korean Chemical Society
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• 제26권4호
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• pp.675-678
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• 2005