• Journal of Oral Medicine and Pain
• /
• 제8권1호
• /
• pp.127-142
• /
• 1983

This thesis was to investigate sex defferencd by employing the methodes of Bernadskij's and it's modification by means of the evaluation of pH of dentin in 162 extracted teeth. The obtained were as follows: 1. In 72% of all experinments, pH of human dentin substance was higher in female than in male. Mean pH was 13.175±0.031 in male and 13.245±0.030 in female. 2. After comparative studies on each pH in anatomical region of tooth arrangement, the sex difference of pH was most obviously showed in molars. 3. In pH change according to ages, the 30's was the highest in male and the 20's in female, also pH showed decresing tendency by the increasing of age in both male and female. 4. There was no pH difference in anatomical regions of tooth arrangment. 5. Mean pH was 13.282±0.013 in under 50 years of age and 13.282±0.022 over 50. It proved that pH was higher in under 50 years of age than in over 50.

• 한국염색가공학회지
• /
• 제13권3호
• /
• pp.155-164
• /
• 2001

Textile wet-processing industry usually five rise to environmental pollution problems caused by using chemical substance. The objective of this study is to apply enzymes for wool and reduce the environmental problems. Three commercial protein degradation enzymes and a cellulose degradation enzyme as a reference were treated to prevent the shrinkage of wool fabric on laundering. Shrink resistant effects used change with the kinds of enzyme, the amount of enzyme, assistant chemicals, and the pre-treatment condition of wool fabric. When pre-treated with corona before enzyme treatment under ultrasonic condition, the weight loss was increased and strength was decreased and elongation was increased. Both corona pre-treatment and the addition of $Na_2SO_4$ also decreased shrinkage of wool fabrics on laundering. The existence of assistant chemicals increased alkali solubility of wool fabrics.

• 생약학회지
• /
• 제2권3호
• /
• pp.121-123
• /
• 1971

In series of the the development of domestic natural products, the studies were conducted to evaluate the pharmacologically active substances of the roots of Pursatilla koreana, which is a specific plant, widely distributed in this country and known to be effective as antiinflammatory, hemostatic and antidysentric agents in oriental remedies. From the hydrolysis of methanol extract of the root, a triterpenic substance was isolated. It was identified as $hederagenin\;C_{30}H_{48}O_4,\; m.p.\;333^{\circ}{\sim}334^{\circ}$, by the m.m.p. with authentic sample, elemental analysis, IR, mass spectra and the other physico-chemical experimentations.

• 대한전기학회:학술대회논문집
• /
• 대한전기학회 2011년도 제42회 하계학술대회
• /
• pp.2130-2131
• /
• 2011

Electric fire breaks out by various causes such as electric short, overload(over current), leakage current, poor contact, static electricity, insulation deterioration, partial disconnection and etc. In this paper, we studied analysis technique for scientific and systematic judgment for distinction of electricity fire existence and nonexistence, and described about electricity fire cause analysis process for collecting physical evidences. We handled external form analysis, Substance extension analysis, X-ray transmission analysis, cross-section analysis, thermal analysis, chemical structure analysis, surface structure analysis, component analysis, electrical properties analysis, and circuit analysis by analysis technique for electricity fire cause judgment. We expect that analysis technic elevation and correct cause of fire analysis of scene of a fire investigators and analysts through this paper which see help.

• 한국비블리아학회지
• /
• 제12권2호
• /
• pp.71-84
• /
• 2001

도서관 소장용 자료의 장기보존에 관한연구를 수행하였는데, 크게 세부분으로 구분된다： 종이, 마이크로 필림(MF), 전산매체. 첫째로, 19~20세기에 생산된 산성용지의 보존대책을 위한 열화원인과 열화도를 평가하여 그 특성을 분석하고, 도서의 보존을 위한 보존환경, 탈산처리 방법을 통한 보존처리의 메카니즘을 연구하였다. 둘째로, 마이크로필림의 보존성을 위한 재료의 물리.화학적 성질, 현상과정의 산화물, 보존수명과 관련된 재료의 원인분석을 하였다. 그리고 셋째로, 전자환경에서의 전산매체의 수명, 저장용량, 생존능력, 노후력 극복 등의 자료의 저장조건과 요구조건 등의 장기보존방안을 제시하였다.

• 환경위생공학
• /
• 제15권3호
• /
• pp.70-74
• /
• 2000

The technology of malodorous substances treatment was classified physical separation and chemical destruction. This study was carried out to investigate the characteristics of malodorous substances treatment with the change of operating conditions from the ozone generator. The major results of this study were as follows : Removal efficiency by additive ozone rate was measured $NH_3$:95%(ozone additive rate : 2), $H_2S$ : 97%(ozone additive rate:4), $CH_3SH$ : 96%(ozone additive rate : 3), $(CH_3)_2S_2$ : 97%(ozone additive rate:5), $(CH_3)_3N$ : 95%(ozone additive rate : 1), $CH_3CHO$ : 95%(ozone additive rate : 2), $C_6H_5CHCH_2$ : 95%(ozone additive rate : 2).

• Journal of Microbiology and Biotechnology
• /
• 제16권12호
• /
• pp.1977-1983
• /
• 2006

Kaempferol was isolated and identified from the methanol extract of the flowers of Impatiens balsamina. Kaempferol showed inhibitory activity against mushroom tyrosinase with an $ID_{50}$ of 0.042 mM. Inhibition kinetics, as determined using a Lineweaver-Burk plot, showed kaempferol to be a competitive inhibitor of mushroom tyrosinase with a $K_i$ value of 0.011 mM. The lag phase of tyrosine hydroxylation catalyzed by mushroom tyrosinase clearly increased on increasing the concentration of kaempferol. In addition to its tyrosinase inhibiting activity, kaempferol strongly inhibited melanin production by Streptomyces bikiniensis, in a dose-dependent manner, without inhibiting cell growth. For comparative purposes, the tyrosinase inhibitory activity of kaempferol was also assayed versus quercetin, a positive standard.

• Applied Biological Chemistry
• /
• 제24권2호
• /
• pp.145-148
• /
• 1981

A study has been conducted to ascertain persistency of p-chlorophenoxy acetic acid (CPA), a plant growth substance, in soil. CPA was extracted from soil and then converted to a gIc (ECD) sensitive derivative, 2-chloroethyl p-chlorophenoxy acetate (CPA ester) with $BCI_3$ as catalyst. Total recovery of CPA including the chemical conversion was 49.4% and detection limit of CPA in soil, a minimum concentration of the compound which can be identified on chromatogram, was 0.03 ppm. Half life of CPA in clay loam under field conditions was 20 days and that of CPA under laboratory condition was 27.4 days respectively.

• 한국전기전자재료학회:학술대회논문집
• /
• 한국전기전자재료학회 2001년도 하계학술대회 논문집
• /
• pp.347-350
• /
• 2001

A typical Mold method is to form a gate electrode, a gate oxide, and emitter tip after fabrication of mold shape using wet-etching of Si substrate. In this study, however, new Mold method using a side wall space structure is used in order to make sharper emitter tip with a gate electrode. Using LPCVD(low pressure chemical vapor deposition), a gate oxide and electrode layer are formed on a Si substrate, and then BPSG(Boro phospher silicate glass) thin film is deposited. After, the BPSG thin film is flowed into a mold as high temperature in order to form a sharp mold structure. Next TiN thin film is deposited as a emitter tip substance. The unfinished device with a glass substrate is bonded by anodic bonding techniques to transfer the emitters to a glass substrate, and Si substrate is etched using KOH-deionized water solution. Finally, we made sharp field emitter array with gate electrode on the glass substrate.

• 한국전기전자재료학회:학술대회논문집
• /
• 한국전기전자재료학회 2002년도 하계학술대회 논문집 Vol.3 No.2
• /
• pp.666-669
• /
• 2002

The differences of the effects of mechanical substance pre-activation in the mills with divers force effect schemes on the self-propagating high temperature synthesis (SHS) of the $SiO_2$ + 37.5% Al system were investigated. The power saturation of activated material state are estimated referring on the variations of dilatometry curve paths. The effects of activation time on the temperature of sample self-ignited in the furnace, combustion temperature and completeness of the quartz reaction with aluminium were determined. The enhancing effects of organic modifiers of quartz particle surfaces on the further SHS synthesis development were shown.