• Journal of Advanced Marine Engineering and Technology
• /
• 제18권1호
• /
• pp.114-122
• /
• 1994

A cold temperature control system for the BAF(batch annealing furnace) has been established in order to reduce energy consumption to imrpove productivity and stabilize the properties of products. Therefore we confirmed a relation between annealing cycle time and atmospheric gas, changing annealing cycle time according to BAF temperature with time during heating and actual temperature measurements cold spot during soaking. The results of the temperature variation effect on the batch annealing are as follows. 1) Cooling rate is increasing gradually with increasing atmospheric gas flow, but heating rate is hardly increasing without atmospheric gas component. Heating time is reduced to one half with increasing atmospheric gas flow rate and changing of atmospheric gas component from HNx to Ax gas and annealing cycle time is reduce to 2.7 times. 2) With enlarging the difference between furnace temperature and soaking temperature at the HNx BAF, heating time becomes short, but cooling time is indifferent. 3) If temperature difference of 300.deg. C in the temperature change of cold spot according to the annealing cycle control temperature, Hi-CON/H2BAF is interchanging at each other at 26hours, but HNxBAF at 50 hours. 4) Soaking time at batch annealing cycle determination is made a decision by the input coil width, and soaking time for quality homogenization of 1219 mm width coil must be 2.5 hours longer then that of 914mm width coil for the same coil weight at Hi-CON/H2BAF. But, it is necessary to make 2 hours longer at HNxBAF.

• 한국정밀공학회지
• /
• 제11권2호
• /
• pp.173-181
• /
• 1994

A Cold spot temperature control system for the batch annealing furnace has been estabilished in order to reduce energy consumption to improve productivity and stabilize the propertics of products. Therefore we confirmed a relation between annealing cycle time and atmospheric gas, variation of coil cold spot temperature with time during heating and actual temperature measurements at mid-width of each coil during heating and actual temperature measurements at mid-width of each coil during soaking. The results of the tempaeature variation effect on the batch annealing are as follows. 1) Heating time is reduced to one half with increasing atmospheric gas flow rate and changing of atmospheric gas component from HNx to Ax gas, and annealing cycle time is reduced to 2.7 times. 2) In case of short time healing, the slowest heating part is the center of B coil, in case of long time heating, the low temperature point moves from the center of coil to inside coil. And the temperature in this part is higher than other parts when cooling. When finished heating, the cold spot is located 1/3 of coil inside in case of HNx atmospheric gas. But center of coil in case of Ax atmospheric gas. 3) The outside of top coil is the highest temperature point when heating, which becomes the lowest temperature point when cooling. So, this point becomes high temperature zone at heating and low temperature zone at cooling, It has relation according to atmospheric gas component and flow rate. 4) Soaking time at batch annealing cycle determination is made a decision by the input coil width, and soaking time for quality homogenization of 1214mm width coil must be 2.5 hours longer than that of 914mm width coil for the same ciol weight. 5) Annealing cycle time with Ax atmospheric gas is extended 1 hour in of slow cooling during 5 hours in order to avoid rapid cooling.

• 대한기계학회논문집
• /
• 제18권5호
• /
• pp.1227-1234
• /
• 1994

A cold spot temperature control system for the batch annealing furnace has been established in order to reduce energy consumption which is essential to improve productivity and stabilize the properties of products. A relationship between annealing cycle time and gas flow rate is developed and also for the variation of coil cold spot temperature with time during heating, and actual temperature measurements at mid-width of each coil during soaking. The results of the temperature variation effect on the cold rolled steel sheet batch annealing are as follows. (1) Cooling rate increasing gradually with increasing atmospheric gas flow, but heating rate is hardly increasing without atmospheric gas component change. (2) In case of short time heating, the slowest heating part is the center of B coil and in case of ling time heating, the low temperature point moves from the center of coil to inside coil. (3) The outside of top coil is the highest temperature point under heating, which becomes the lowest temperature point under cooling. (4) Soaking time determination depends on the input coil width, and soaking time for quality homogenization of 1214 mm width coil must be 2 hours longer than that of 914 mm width coil.

• Nuclear Engineering and Technology
• /
• 제21권4호
• /
• pp.294-301
• /
• 1989

상하부 2개의 노외계측기, 노입구관 온도 및 제어봉 위치 신호를 이용하여 상세한 축방향 출력분포를 계산할 수 있는 APDMS프로그램을 개발하였다. 상하부 2개의 노외계측기 신호가 제어봉 위치에 의하여 결정된 제어봉 간섭계수와 노입구관 온도에 따른 온도 간섭계수에 대하여 보정된 후 노심 주변출력을 얻기 위하여 보정된 노외계측기 신호에 shape annealing matrix가 적용되었다. 노심의 상하부 경계에서의 출력을 얻기 위해서는 평균 노심출력과 주변출력과의 선형적 관계를 이용한 노심 상하부의 평균출력에 경계점 출력보정계수가 적용되었다. 축방향 출력분포가 2개의 노외계측기에 의해 계산된 상하부 평균 노심출력, 상하부 경계면에서의 출력 및 미리 계산된 노심의 중심 위치에서의 출력을 이용하여 spline approximation에 의하여 계산되었다. 연소도, 출력준위, 제어봉 위치 및 axial offset의 변화에도 불구하고 고리 3호기 4주기에 대하여 BOXER 코드와 APDMS 프로그램에 의해 계산된 축방향 출력분포의 비교는 5% root mean square 오차내에서 일치함을 보여 주었다.

• Korean Chemical Engineering Research
• /
• 제50권1호
• /
• pp.25-29
• /
• 2012

루타일(rutile) $TiO_2$ 분말의 알칼리 수열합성과 $300{\sim}500^{\circ}C$ 열처리를 통해 $TiO_2$ 나노튜브를 제조하고, 이를 리튬이 차전지의 음극 활물질로 채택하여 그 물성과 전기화학적 특성을 조사하였다. 수열반응 직후의 정제과정에서 불순물인 미세분진을 완전히 제거하여 제조된 $TiO_2$ 나노튜브는 고비표면적과 확연한 나노튜브 결정상을 보였다. 또한 열처리 온도가 증가함에 따라 등방적으로 분산된 나노튜브들이 서로 응집되어 비표면적의 감소를 초래하였다. $300^{\circ}C$ 열처리한 $TiO_2$ 나노튜브가 250 mAh $g^{-1}$의 가장 높은 초기 방전용량을 나타내었으며, 사이클과 고율 특성은 $400^{\circ}C$ 열처리한 시료가 가장 우수한 성능을 보였다.

• 미생물학회지
• /
• 제44권3호
• /
• pp.203-211
• /
• 2008

Shiga 독소 생성 대장균(Shiga toxin-producing Escherichia coli; STEC)을 가장 빠르게 검출할 수 있는 초고속 이단계 PCR 방법을 개발하였다. 검색 대상 유전자는 STEC에서 생성되는 Shiga 독소(Shiga toxin; Stx)를 암호화하고 있는 유전자 stx1이며, 1쌍의 stx 유전자 특이 primer를 사용하여 검출을 수행하였다. 초고속 PCR (Ultra-rapid PCR)은 microchip 기반의 6 ${\mu}l$ PCR 용량의 Real-time PCR을 사용하고, PCR 회전의 각 단계 중 혼성과 중합을 한 단계로 하였을 뿐 아니라, 각 단계의 적용시간을 각 1초, 3초(해리, 혼성/중합)가 되게 극단적으로 줄여, 검사소요시간을 최소화하였다. 35회전의 PCR 진단에 사용된 시간은 6분38초였으며, 용융온도분석에서 stx1 특이 유전자가 검출되었음을 확인하는 데까지 총 7분 28초가 소요되었다. 또한 민감도 측정에서 $3{\times}10^0$ CFU/reaction까지 성공적으로 검출 가능함이 확인되었고, 용융온도분석에서 이 증폭산물은 일정한 $81.42{\pm}0.34^{\circ}C$의 용융온도를 갖는 것으로 확인되었다. 이 검사법을 다양한 STEC 균주들에게 적용하여 그 성능을 검증하였으며, 이로써 본 초고속 이단계 PCR 방법은 Shiga 독소 생성 대장균의 초신속 검출에 바로 적용될 수 있을 것으로 기대한다.

• 한국식품조리과학회지
• /
• 제22권5호통권95호
• /
• pp.659-665
• /
• 2006

밀전분으로 가열-냉각과정에 의해 제조한 RS3와 가교결합에 의한 RS4를 박력분에 대해 10, 20, 30% 혼합하여 밀가루의 특성을 측정하고 쿠키를 제조하여 그 품질을 이화학적 및 관능적 특성으로 비교하였다. RS를 첨가하면 밀가루의 단백질 함량이 감소하였으며 저항전분 함량은 7.0%에서 9.6-17.9%로 증가하였으며 RS4 첨가 시 그 증가폭이 컸다. RS 혼합 밀가루의 팽윤력은 약간 감소하였으나 용해도는 RS3 첨가 시 2-3배 증가하였다. 신속점도측정기에 의한 RS 혼합 밀가루의 호화개시온도는 높아졌으나 최고점도, 유지점도, 냉각점도는 감소하였는데 첨가량이 증가할수록 그 감소 정도가 컸다. RS 첨가 밀가루의 breakdown과 total setback viscosity가 감소하여 RS 첨가로 전분의 노화가 억제 될 것으로 생각되었다. 황색도는 RS3 첨가 시 증가하였으나 RS4 첨가로 감소하였다. 관능평가 결과 RS 첨가는 쿠키의 모양, 색깔, 전체적인 품질이 유의적인 차이를 보였으며(p<0.05), AACC 표준쿠키에서 모양과 색깔이 RS를 첨가한 경우 개선되었다. RS 첨가로 쿠키의 텍스쳐도 영향을 주었으며 전체적인 품질은 땅콩쿠키나 AACC 표준쿠키 모두 RS를 첨가한 경우 개선됨을 알 수 있었다. RS3와 RS4를 밀가루 기준으로 30% 첨가하여 쿠키를 제조하면 저항전분 함량은 6.4%와 10.9% 증가하면서 품질도 개선하였다.

• 한국진공학회:학술대회논문집
• /
• 한국진공학회 2013년도 제45회 하계 정기학술대회 초록집
• /
• pp.88-89
• /
• 2013

A variety of influenza A viruses from animal hosts are continuously prevalent throughout the world which cause human epidemics resulting millions of human infections and enormous industrial and economic damages. Thus, early diagnosis of such pathogen is of paramount importance for biomedical examination and public healthcare screening. To approach this issue, here we propose a fully integrated Rotary genetic analysis system, called Rotary Genetic Analyzer, for on-site detection of influenza A viruses with high speed. The Rotary Genetic Analyzer is made up of four parts including a disposable microchip, a servo motor for precise and high rate spinning of the chip, thermal blocks for temperature control, and a miniaturized optical fluorescence detector as shown Fig. 1. A thermal block made from duralumin is integrated with a film heater at the bottom and a resistance temperature detector (RTD) in the middle. For the efficient performance of RT-PCR, three thermal blocks are placed on the Rotary stage and the temperature of each block is corresponded to the thermal cycling, namely $95^{\circ}C$ (denature), $58^{\circ}C$ (annealing), and $72^{\circ}C$ (extension). Rotary RT-PCR was performed to amplify the target gene which was monitored by an optical fluorescent detector above the extension block. A disposable microdevice (10 cm diameter) consists of a solid-phase extraction based sample pretreatment unit, bead chamber, and 4 ${\mu}L$ of the PCR chamber as shown Fig. 2. The microchip is fabricated using a patterned polycarbonate (PC) sheet with 1 mm thickness and a PC film with 130 ${\mu}m$ thickness, which layers are thermally bonded at $138^{\circ}C$ using acetone vapour. Silicatreated microglass beads with 150~212 ${\mu}L$ diameter are introduced into the sample pretreatment chambers and held in place by weir structure for construction of solid-phase extraction system. Fig. 3 shows strobed images of sequential loading of three samples. Three samples were loaded into the reservoir simultaneously (Fig. 3A), then the influenza A H3N2 viral RNA sample was loaded at 5000 RPM for 10 sec (Fig. 3B). Washing buffer was followed at 5000 RPM for 5 min (Fig. 3C), and angular frequency was decreased to 100 RPM for siphon priming of PCR cocktail to the channel as shown in Figure 3D. Finally the PCR cocktail was loaded to the bead chamber at 2000 RPM for 10 sec, and then RPM was increased up to 5000 RPM for 1 min to obtain the as much as PCR cocktail containing the RNA template (Fig. 3E). In this system, the wastes from RNA samples and washing buffer were transported to the waste chamber, which is fully filled to the chamber with precise optimization. Then, the PCR cocktail was able to transport to the PCR chamber. Fig. 3F shows the final image of the sample pretreatment. PCR cocktail containing RNA template is successfully isolated from waste. To detect the influenza A H3N2 virus, the purified RNA with PCR cocktail in the PCR chamber was amplified by using performed the RNA capture on the proposed microdevice. The fluorescence images were described in Figure 4A at the 0, 40 cycles. The fluorescence signal (40 cycle) was drastically increased confirming the influenza A H3N2 virus. The real-time profiles were successfully obtained using the optical fluorescence detector as shown in Figure 4B. The Rotary PCR and off-chip PCR were compared with same amount of influenza A H3N2 virus. The Ct value of Rotary PCR was smaller than the off-chip PCR without contamination. The whole process of the sample pretreatment and RT-PCR could be accomplished in 30 min on the fully integrated Rotary Genetic Analyzer system. We have demonstrated a fully integrated and portable Rotary Genetic Analyzer for detection of the gene expression of influenza A virus, which has 'Sample-in-answer-out' capability including sample pretreatment, rotary amplification, and optical detection. Target gene amplification was real-time monitored using the integrated Rotary Genetic Analyzer system.