• 대한치과기공학회지
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• 제42권3호
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• pp.202-207
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• 2020

Purpose: This study is a comparative analysis of the strain according to deposition in a constant temperature water bath after manufacturing ultraviolet (UV)-cured artificial teeth. Methods: As a control group, 10 ready-made artificial teeth were selected as the first molar on the right side of the maxilla (RT group). Silicone was used as a duplicate of the artificial denture teeth. Experimental teeth were prepared in two groups using the prepared silicone mold. In the first experimental group, the UV-cured resin was injected into the negative silicone, followed by irradiation with a UV-curing machine for 5 minutes (5M group). In the second experimental group, the UV-cured resin was injected into the negative silicone, and then irradiated for 30 minutes using a UV-curing machine (30M group). The one-way ANOVA was performed, and post-test was analyzed by Tukey. Results: When immersed in a water bath for 15 days, it was found to be -0.3% in the RT group, -0.6% in the 5M group, and -0.7% in the 30M group. The results revealed -0.2% in the RT group, 0.2% in the 5M group, and -0.2% in the 30M group when they were in the bath for 30 days. Conclusion: In the water bath, the swelling was greater when deposited for 1 to 15 days, but was less when deposited for 15 to 30 days.

• The Korean Journal of Physiology
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• 제1권1호
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• pp.67-72
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• 1967

Present paper is attempted to introduce the phenomenon of 'after contraction' in isolated cardiac-muscle. Papillary muscles were removed from cat right ventricle and were used as a preparation. The muscle strip was Placed in tissue bath which is kept in steady temperature of around $25^{\circ}C$ and was perfuced by Tyrode solution, saturated with 95% $O_2$ and 5% $CO_2.$ under the condition of high calcium (8.2-10.0 mM/l), low sodium (72.4-70.0 mM/l) perfusion with the administration of epinephrine (1-2 mg/l) into tile tissue bath normally triggered muscle contraction was followed by oscillatory, repetitive contractions - after contraction. The phenomenon of after contraction was augumented by decrease in tissue bath temperature and by increase in number of preceding beats and in driving rate. Authors were able to maintain the phenomenon in prominent and steady state giving proper experimental conditions such as fixed bath temperature (ranged from $22^{\circ}C\;to\;27^{\circ}C$), suitable driving rate (20 per minute in average) and perfusion of high calcium, loll sodium and 1-2 mg/l of epinephrine. In some preparations, the strength of after contraction (second contraction) reached up-to 80% of normally triggered contraction and five repetitive contractions were observed as largest number of after contractions. Intracellular action potential measured in the muscle which was beating regulary showing steady after contraction revealed no oscillating after potential in most parts of the muscle but in few cases oscillating changes of after potentials were detectable. In electrogram of the muscle preparation recorded by means of contact electrode prominent, oscillating after potentials were observable when the recorder was set at highest sensitivity. It still is not clear that whether after contraction is the phenomenon which corresponds to those changes in action potential, oscillating after potential, of the muscle preparation. Possible mechanism of the phenomenon of after contraction relating with after potential changes was proposed. Detailed results obtained from further studies on after contraction and concrete discussion on the phenomenon will be reported by authors.

• KSBB Journal
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• 제22권4호
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• pp.197-200
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• 2007

식물세포배양으로부터 paclitaxel을 효율적으로 대량추출하기 위한 추출액의 여과 및 농축 조건을 최적화하였다. 메탄올을 이용한 biomass 추출물을 여과할 경우, biomass 대비 6% (w/w) 여과보조제인 규조토를 첨가할 경우 여과시간 단축에 가장 효과적임을 알 수 있었다. 규조토 6% (w/w) 첨가를 통하여 1회 biomass 추출물 여과 시 4.2%, 2회 추출물 여과 시 30.3%, 3회 추출물 여과 시 22.8%, 4회 추출물 여과 시 19.0%의 여과시간 단축 효과를 각각 얻을 수 있었다. 여과액의 농축은 paclitaxel 순도 및 수율을 고려할 때 rotary evaporator의 bath 온도를 50$^{\circ}C$ 이하로 운전하는 것이 바람직하였으며, 이때 농축액의 온도는 증발잠열 때문에 실제 bath의 온도보다는 상당히 낮음을 알 수 있었다. 또한 여과액의 농축 완료 시점은 paclitaxel 순도, 수율, 농축시간, 액-액 추출에서의 상 분리 시간 등을 고려할 때 농축액의 비중이 0.95에서 종료하는 것이 가장 적당함을 알 수 있었다.

• 한국표면공학회지
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• 제42권4호
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• pp.152-156
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• 2009

Electroless plating is influenced by kinds of parameters including concentrations of electrolyte, plating time, temperature and so on. In this study, the Pt thin films were prepared on GaAs substrate by a 2-step electroless plating depending method. The small Pt catalytic particles by using Pt I bath exhibited islands-morphology dispersed throughout the substrate surface at $65^{\circ}C$, as function as a sensitized thin film, and then a thicker Pt film grew upon the sensitized layer by the second Pt II bath. As the growth of Pt film is strongly influenced by the plating time and temperature, the plating time of Pt II bath varied from 5 min to 40 min at $60{\sim}80^{\circ}C$ after Pt I bath at $60{\sim}80^{\circ}C$ for 5 min. It is found that the film grows with the increasing plating time and temperature. The resistivity value of Pt deposited layer was characterized to study the growth mechanism of 2-step plating.

• 한국염색가공학회지
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• 제19권1호
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• pp.1-11
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• 2007

Dyeing of polyester/cotton blends is usually carried out through the two-bath or one-bath two-step dyeing method using proper disperse dyes and reactive dyes for each fiber. However, the dyeing requires relatively long and complicated procedure as well as there are some problems such as lower dyeability. In the present study, new one-bath one-step dyeing process was investigated using disperse dyes having amino groups and hetero-bifunctional bridge compound(DBDCBS) including dichloro-s-triazinyl groups and ${\alpha},{\beta}$-dibromopropionylamido groups to improve the dyeability of cotton component in polyester/cotton blends. And the one-bath dyeing properties of polyester/cotton blends was evaluated by various dyeing conditions such as pH, temperature and dye concentration, The optimum dyeing condition was pH 4 and $110-120^{\circ}C$. Color fastness were relatively good because of the colvalent bond formation between DBDCBS-reacted cotton fiber and disperse dye.

• 한국표면공학회지
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• 제43권2호
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• pp.47-50
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• 2010

This work discusses a two-step electroless plating method for preparing a Pt thin film on p-type InGaAs substrate, which is defined as Pt I and Pt II. A thin Pt catalytic layer formed in Pt I bath on the substrate at $65^{\circ}C$. In the following Pt II bath, thick Pt films then easily grew on the sensitized layer on InGaAs previously formed in the Pt I bath. The growth of Pt film is strongly influenced by the plating temperature and pH value. To study the plating time effect, the plating of Pt II bath is 5 to 40 min at $80^{\circ}C$ after using Pt I bath at 50~$65^{\circ}C$ for 5min of pH 8~13. Pt film for ohmic contact to p-type InGaAs was successfully prepared by using the two-step Pt electroless plating.

• 센서학회지
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• 제25권1호
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• pp.65-70
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• 2016

We devised a method to control the temperature of a liquid bath as low as $-100^{\circ}C$ using the duty cycle control of a solenoid valve. The solenoid valve controls the flow of liquid nitrogen that we used as a cryogen in this system. By controlling the duty cycle of a solenoid valve using feedback from the measured temperature of the liquid bath, we were able to achieve temperature stability within ${\pm}19mK$ around $-100^{\circ}C$. We also demonstrated that by taking average values of the temperature readings for sequence of measurements from more than one thermometer, it is possible to use this system for the calibration of thermometers within 3 mK. This system and the control method can be used for the precise temperature control in the range between $0^{\circ}C$ and $-100^{\circ}C$, where commercially available precision baths are much expensive and hard to be built in customized configurations.

• 한국염색가공학회지
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• 제9권3호
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• pp.10-17
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• 1997

The study was performed to obtain the optimum extraction conditions for crocin from gardenia fructus. Generally crocin is unstable on heat, light, acid and base solution. The extraction efficiency of crocin from gardenia depended upon the extraction time, extraction temperature, pH in the extraction bath and the optimum conditions of crocin extraction were determined as 60 minutes of extraction time, 4$0^{\circ}C$ of extraction temperature, pH 7 of extraction bath. The molar extinction coefficient of crocin was 12,515 and the color yield of purified crocin was about six times higher than that of non-purified crocin. The heat-stability at extraction temperature and lightstability in irradiation with xenon lamp for one hour of the purified crocin were higher than those of non-purified crocin. Intensity of &{\lambda}_{max}&of crocin was decreased by irradiation for one hour but UV-Vis. spectra of crocin was not changed. The colors of purified and non-purified crocin dissolved wit methanol was evaluated by means of CIE L* a* b* system.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2009년도 제40회 하계학술대회
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• pp.1529_1530
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• 2009

The process conditions for fabricating p-type silicon pillars were optimized by controlling current density, bath temperature. To get best process flexibility for pillar arrays formation, three factors affecting pillar formation were changed. First, the solution bath was designed to keep constant temperature during the experiment irrespective of external temperature. Second, the counter Pt electrode was changed from rod type to mesh to obtain uniform distribution of current density. Third, Cr-Cu alloy electrode instead of Cu was used to increase electrode current density.

• 한국염색가공학회지
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• 제11권5호
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• pp.1-6
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• 1999

This study was carried out to investigate the effect of a scouring machine including an ultrasonic system on desizing and scouring polyester fabrics. The ultrasonic frequency of the improved machine showed up at 28.882 kHz. Frequency amplitude increased with the current and the bath temperature, and then showed a constant level. Scouring effect of the ultrasonic machine was better than that of the conventional scouring machine using the mechanical stirring. The ultrasonic machine showed the optimum scouring effect at $50^\circ{C}$ of bath temperature and 10 min. of operation time, as compared to the conventional machine that required operating conditions of high temperature at $90^\circ{C}$, stirring speed at 40 rpm, and stirring time for 15 min..