• Journal of Preventive Medicine and Public Health
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• 제7권1호
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• pp.107-113
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• 1974

위생공학에서 하수나 공장폐수를 처리할 때 이용하는 생물학적 처리과정은 미생물에서 생성되는 효소에 의하여 이루어 진다. 본 연구에서는 diastase의 활성에 대하여 수소이온 농도, 온도, 기질 농도 및 방해물질 등 여러가지 요인이 미치는 영향을 실험적으로 관찰하여 다음과 같은 결론을 얻었다. (1) diastase의 활성도는 pH $4.0{\sim}7.0$의 범위가 적당하였고 최적치는 pH 5.0이었다. (2) diastase의 활성도는 $30^{\circ}C{\sim}50^{\circ}C$ 높았으며 최적온도는 $40^{\circ}C$였다. (3) 기질농도의 영향을 보면 녹말농도 $750{\mu}g/ml$까지는 diastase의 활성도가 급격히 증가하였고, 그 이후에는 한정속도를 나타냈다. Michaelis 방정식을 적용시켜 보면 한정속도는 $415{\mu}g/ml$ starch removed/ml of reaction mixture/min였고 Michaelis 상수는 $340{\mu}g/ml$였다. (4) 방해물질의 영향을 보면 NaCl 농도 1.0%, $HgCl_2$ 농도 0.001%에서 diastase의 활성은 완전히 억제되었다.

• 한국환경보건학회지
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• 제4권1호
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• pp.23-25
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• 1977

Transaminase has been a popular methods in the clinical laboratory for the diagnosis of particular diseases. The methods we are familiar with should be considered further on the serum states provided on the test to be done. (serum freshness, temperature and duration preserved) I have studied transaminase activities of the serum preserved under frozen (-10$\circ$C), refrigerated (4$\circ$C) and room temperature conditions. At a given interval those activities of serum are measured and then the results are compared with the optical density and calculated for the standard deviation and percent variation (Table 1. & Fig. 1.) G.O.T. activity is maintained decreased at a relatively constant rate from 2nd day to 14th day preservation under frozen and refrigerated but its activity variation at 25$\circ$C are far greater than the above conditions throughout the test periods. Elevated G.P.T. level of serum compared with G.O.T. are remained at any temperature and duration. Unless the determination of amino acid level study can not ruled out clearly.

• Journal of Plant Biology
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• 제34권3호
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• pp.215-221
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• 1991

Photoxynthetic properties of polyvinylalcohol (PVA)-immobilized chloroplast especially regarded to stability of photosynthetic electron transport and the fluorescence induction pattern were studied. When isolated spinach chloroplasts were immobilized with PVA, it showed good preservation of photosynthetic electron transport activity, especially PS II activity, during storage at -15$^{\circ}C$, 4$^{\circ}C$ and 2$0^{\circ}C$. And immobilized chloroplasts revealed similar thermostability of whole chain electron transport to free chloroplsts. And the absorption peak of red band of chloroplasts showed the blue-shift of 2-4 nm after immobilization. Fv/Fm ratio of chlorophyll fluorescence slightly decreased after immobilization. White light pulse after continuous light do not induced the additional fluorescence rise. This means chlorophyll fluorescence at room temperature reached to Fmax under continuous light in the immobilized chloroplasts. It seems that PVA may be a good candidate for immobilization matrix for the preservation of photosynthetic function of thylakoids and for the continuous use of chloroplast membranes of higher plants for solar energy storage and conversion.

• 한국균학회지
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• 제8권2호
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• pp.85-88
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• 1980

The antifungal activity of salicylaldehyde-o-phenylenediimine, a derivative of Schiff base, was studied in vitro against various species of fungi, especially, dermatophytes. The antifungal tests were performed according to the tube-dilution method, and all subcultures were incubated at room temperature for 14 days. Salicylaldehyde-o-phenylenediimine was effective against fungi such as Trichophyton mentagrophytes, Trichophyton rubrum, Microsporum canis and Fonsecaea compacta. Trichophyton mentagrophytes was inhibited at $20{\mu}g$ per ml, Trichophyton rubrum at $40{\mu}g$ per ml, Microsporum canis at $6{\mu}g$ per ml, and Fonsecaea compacta at $2{\mu}g$ per ml.

• Progress in Superconductivity
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• 제4권1호
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• pp.48-52
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• 2002

When applying a SQUID system for diagnosing heart disease, it is informative to obtain the source current distributions from the measured MCG (magnetocardiogram) signals since the bioelectric activity in the heart is generally represented by distributed current sources. In order to estimate the Primary current distribution in a heart, the minimum norm estimate was computed, assuming a source plane below the chest surface. In the simulation, current distributions, which were computed for the test dipoles represented well the essential feature of the test-current configurations. Source current reconstruction was performed for MCG signal of a healthy volunteer, which was recorded using a 40-channel SQUID system in a magnetically shielded room. It was found that the obtained current distribution is consistent with the electrical activity in a heart.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2002년도 하계학술대회 논문집 D
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• pp.2724-2726
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• 2002

The effect which electromagnetic wave has influence on visual activity of human, was investigated in this study. The EEG and the EOG generated by the rays of LED were measured in shield room when the subject were exposed at electromagnetic wave(820MHz, 2mV) or not exposed. Each component of the EEG was compared and evaluated on being exposed at electromagnetic wave or not. As a result was $\alpha$ wave was represented relatively low level in the case of exposed at electromagnetic wave and $\beta$ wave was represented relatively low level in the case of not exposed.

• Bulletin of the Korean Chemical Society
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• 제35권2호
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• pp.551-556
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• 2014

The treatment of alkylated nitro derivatives of indazole with 2-(4-chlorophenyl)acetonitrile under basic conditions gave the new 8-chloro-3-alkyl-3H-pyrazolo[4,3-a]acridine-11-carbonitriles via the nucleophilic substitution of hydrogen which proceeds at room temperature with concomitant cyclisation in fairly good yields. The structures of all newly synthesized compounds were confirmed by IR, $^1H$ NMR, $^{13}C$ NMR and mass spectral data. Fluorescence experimental results of all newly synthesized compounds revealed remarkable photoluminescence properties and strong green fluorescence properties. Also, the new compounds exhibited potent antibacterial activity and their antibacterial activity (MIC) against Gram positive (Staphylococcuse aureus methicillin resistant S. aureus and Bacillus subtilis) and negative bacterial (Pseudomonas aeruginosa and Escherichia coli) species were determined.

• 전기학회논문지
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• 제64권8호
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• pp.1240-1245
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• 2015

The purpose of this paper is to investigate the autonomic nervous system activity in various ambient temperatures. To evaluate autonomic function, we use the frequency domain analysis of heart rate variability such as FFT(fast fourier transformation), AR(Auto-Regressive) model and Lomb-Scargle peridogram. HRV(heart rate variability) is calculated by using ECG recorded from 3 different temperature room which temperature is controlled in 18℃(low), 25℃(mid) and 38℃(high), respectively. Totally 22 subjects were participated in the experiment. In the results, the most significant autonomic changes caused by temperature load were found in the HF(high frequency) component of FFT and AR model. And the HF power is decreased by increasing temperature. Significance level was increased by increasing the difference of temperatures.

• Bulletin of the Korean Chemical Society
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• 제30권4호
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• pp.781-782
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• 2009

• Carbon letters
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• 제27권
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• pp.42-49
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• 2018

A citric acid functionalized graphene oxide nanocomposite was successfully synthesized and the structure and morphology of the nanocatalyst were comprehensively characterized by Fourier transform infrared spectroscopy, energy-dispersive X-ray analysis, X-ray diffraction patterns, atomic force microscopy images, scanning electron microscopy images, transmission electron microscopy images, and thermogravimetric analysis. The application of this nanocatalyst was exemplified in an important condensation reaction to give imidazole derivatives in high yields and short reaction times at room temperature. The catalyst shows high catalytic activity and could be reused after simple work up and easy purification for at least six cycles without significant loss of activity, which indicates efficient immobilizing of citrate groups on the surface of graphene oxide sheets.