• Title/Summary/Keyword: isolation temperature

Search Result 632, Processing Time 0.023 seconds

Improvement of Damage Range Calculation for First Response to Chemical Accidents (화학사고의 일차 대응을 위한 피해영향범위 산정 개선 방안)

  • Lee, Deok Jae;Ahn, Jae-Hyun;Song, Chang Geun
    • Journal of the Korean Society of Safety
    • /
    • v.32 no.2
    • /
    • pp.59-65
    • /
    • 2017
  • Calculation of the damage impact of chemical accidents is an important element in site, and the initial isolation distance and the protective action distances are significant factors in coping the chemical accident. In this study, three major cities that represent each Province were selected, and the safety distances were calculated considering regional climate conditions. The results were compared with the prescribed values in Emergency Response Guidebook. It is concluded that the regional meteorological conditions such as temperature, vapour pressure, relative humidity, wind speed, and cloud cover should be reflected in estimating the initial isolation distance and the protective action distance.

Selective Si Epitaxy for Device Isolation (소자분리를 위한 선택적 실리콘 에피택시)

  • Yang, Jeon Wook;Cho, Kyoung Ik;Park, Sin Chong
    • Journal of the Korean Institute of Telematics and Electronics
    • /
    • v.23 no.6
    • /
    • pp.801-806
    • /
    • 1986
  • The effect of SiH2Cl2 -HCl gas on the growth rate of epitaxial layer is studied. The temperature, pressure and gas mixing ratio of SiH2Cl2 and HCl are varied to study the growth rate dependence and selective Si epitaxy. The P-n junction diode is fabricated on the epitaxial layer and electrical characteristics are examined. Also, using selective Si epitaxy, a possibility of thin dielectric isolation process, that gives an independent isolation width on the mask dimension, is examined.

  • PDF

Three Dimensional Silicon Accelerometer for High Temperature Range (고온용 3차원 실리콘 가속도센서)

  • Son, Mi-Jung;Seo, Hee-Don
    • Proceedings of the KIEE Conference
    • /
    • 1998.07g
    • /
    • pp.2504-2508
    • /
    • 1998
  • In this paper, we propose the new detecting method for three dimensional piezoresistive silicon accelerometer. Furthermore the accelerometer is formed to have endurance for high temperature by perfect isolation of the piezoresistors using Silicon On Insulator(SOI) wafer. Sensor size are optimized with analytical formulae and extended with FEM simulation for the more detailed results. The accelerometer was fabricated by bulk micromachining techonology. We measured the temperature characteristics and the output characteristics, and the both characteristics were compared with the simulated results

  • PDF

Comparison of Total RNA Isolation Methods for Analysis of Immune-Related microRNAs in Market Milks

  • Oh, Sangnam;Park, Mi Ri;Son, Seok Jun;Kim, Younghoon
    • Food Science of Animal Resources
    • /
    • v.35 no.4
    • /
    • pp.459-465
    • /
    • 2015
  • Bovine milk provides essential nutrients, including immunologically important molecules, as the primary source of nutrition to newborns. Recent studies showed that RNAs from bovine milk contain immune-related microRNAs (miRNA) that regulate various immune systems. To evaluate the biological and immunological activity of miRNAs from milk products, isolation methods need to be established. Six methods for extracting total RNAs from bovine colostrums were adopted to evaluate the isolating efficiency and expression of miRNAs. Total RNA from milk was presented in formulation of small RNAs, rather than ribosomal RNAs. Column-combined phenol isolating methods showed high recovery of total RNAs, especially the commercial columns for biofluid samples, which demonstrated outstanding efficiency for recovering miRNAs. We also evaluated the quantity of five immune-related miRNAs (miR-93, miR-106a, miR-155, miR-181a, miR-451) in milk processed by temperature treatments including low temperature for long time (LTLT, 63℃ for 30 min)-, high temperature for short time (HTST, 75℃ for 15 s)-, and ultra heat treatment (UHT, 120-130℃ for 0.5-4 s). All targeted miRNAs had significantly reduced levels in processed milks compared to colostrum and raw mature milk. Interestingly, the amount of immune-related miRNAs from HTST milk was more resistant than those of LTLT and UHT milks. Our present study examined defined methods of RNA isolation and quantification of immune-specific miRNAs from small volumes of milk for use in further analysis.

A Study on the Diplexer Switch of High Isolation Using Varactor Diode (바랙터 다이오드를 이용한 높은 격리도를 갖는 DIPLEXER 스위치에 관한 연구)

  • Kang Myung-Soo;Park Jun-Seok
    • The Transactions of the Korean Institute of Electrical Engineers C
    • /
    • v.54 no.4
    • /
    • pp.178-184
    • /
    • 2005
  • In this paper, using diplexer structure and varactor diode controlled by reverse bias voltage for diplexer switch gives possibilities to improve isolation and current characteristics. 1 have newly designed switch with high isolation by application varactor diode corresponding to capacitor of diplexer. The low-pass filter for proposed tunable diplexer passes the microwave signal in the bandwidth for wireless cellular network systems and high-pass filter passes it in the bandwidth for wireless personal communication services (PCS) network systems. As the capacitance of the low-pass filter increases, the cut-off frequency can be moved to low frequency, so that the switch is on state in cellular bandwidth and off state in the PCS bandwidth, in contrast to, as the capacitance for attenuation characteristic of high-pass filter increases, it can be moved to high frequency, so that the switch is off state and on state in the cellular bandwidth. it is possible to improve isolation and current consumption characteristics by application diplexer design methods and varactor diode. 1 expect that the tunable diplexer circuit and design methods should be able to find applications on MMIC and low temperature copired ceramic (LTCC).

Effect of Thermal Budget of BPSG flow on the Device Characteristics in Sub-Micron CMOS DRAMs (서브마이크론 CMOS DRAM의 소자 특성에 대한 BPSG Flow 열처리 영향)

  • Lee, Sang-Gyu;Kim, Jeong-Tae;Go, Cheol-Gi
    • Korean Journal of Materials Research
    • /
    • v.1 no.3
    • /
    • pp.132-138
    • /
    • 1991
  • A comparision was made on the influence of BPSG flow temperatures on the electrical properties in submicron CMOS DRAMs containing two BPSG layers. Three different combinations of BPSG flow temperature such as $850^{\circ}C/850^{\circ}C,\;850^{\circ}C/900^{\circ}C,\;and\;900^{\circ}C/900^{\circ}C$ were employed and analyzed in terms of threshold, breakdown and isolation voltage along with sheet resistance and contact resistance. In case of $900^{\circ}C/900^{\circ}C$ flow, the threshold voltage of NMOS was decreased rapidly in channel length less than $0.8\mu\textrm{m}$ with no noticeable change in PMOS and a drastic decrease in breakdown voltages of NMOS and PMOS was observed in channel length less than and equal to $0.7\mu\textrm{m}$ and $0.8\mu\textrm{m}$, respectively. Little changes in threshold and breakdown voltages of NMOS and PMOS, however, were shown down to channel length of $0.6\mu\textrm{m}$ in case of $850^{\circ}C/850^{\circ}C$ flow. The isolation voltage was increased with decreasing BPSG flow temperature. A significant increase in the sheet resistance and contact resistance was noticeable with decreasing BPSG flow temperature from $900^{\circ}C$ to $850^{\circ}C$. All these observations were rationalized in terms of dopant diffusion and activation upon BPSG flow temperature. Some suggestions for improving contact resistance were made.

  • PDF

The Effect of Graphite Addition and Pouring Temperature on the Coating State in Vaccum Process (감압조형시 흑연첨가 및 주입온도가 피복상태에 미치는 영향)

  • 조성준
    • Journal of the Korean Ceramic Society
    • /
    • v.34 no.5
    • /
    • pp.544-551
    • /
    • 1997
  • We tried to improve the coating capability of the coating material using an additive(hexagonal cystalline graphite) of 2%, 3%, 4% and 6% under various pouring temperature for the easy isolation of sand and coating material from the final product. As a result in case of using a 2% and 3% additive generally no burning state has been occurred under the low pouring temperature, but it has been gradually increased with the pouring temperature. On the other hand in case of using a 4% and 6% additive there has been no burning state through out the whole pouring temperature. From this result we could see that the best state of the final product without sand and coating material could generally be obtained if 4% and/or 6% of the crystalline graphite and the pouring temperature of 140$0^{\circ}C$$\pm$5$^{\circ}C$ would be used.

  • PDF

Development of the high temperature silicon pressure sensor (고온용 실리콘 압력센서 개발)

  • Kim, Mi-Mok;Chul, Nam-Tae;Lee, Young-Tae
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
    • /
    • 2003.07a
    • /
    • pp.147-150
    • /
    • 2003
  • In this paper, We fabricated a high temperature pressure sensor using SBD(silicon- direct-bonding) wafer of $Si/SiO_2$/Si-sub structure. This sensor was very sensitive because the piezoresistor is fabricated by single crystal silicon of the first layer of SDB wafer. Also, it was possible to operate the sensor at high temperature over $120^{\circ}C$ which is the temperature limitation of general silicon sensor because the piezoresistor was dielectric isolation from silicon substrate using silicon dioxide of the second layer. The sensitivity of this sensor is very high as the measured result of D2200 shows $183.6\;{\mu}V/V{\cdot}kPa$. Also, the output characteristic of linearity was very good. This sensor was available at high temperature as $300^{\circ}C$.

  • PDF

Isolation and Identification of Lactobacilli from Fermented Sausages (발효소시지로부터 유산생성균의 분리 및 동정)

  • 고명수;이명섭;김창한
    • Microbiology and Biotechnology Letters
    • /
    • v.22 no.5
    • /
    • pp.544-549
    • /
    • 1994
  • Lactobacilli proliferating in fermented sausages of the specific ripening conditions were isolated from fermented sausages, manufactured in the absence of an added starter, during ripening under controlled temperature-humidity conditions. Based on morphological, physiological and bio- chemical characteristics and carbohydrate fermentation of isolated strains, three strains of isolates were identified as Lactobacillus curvatus, two strains as Lactobacillus sake. Optimal temperature and pH for growth of isolated strains were 30$\circ$C and pH 6.0~7.0, respectively. These strains were salt tolerant, multiplying in the presense of 6~8% NaCl.

  • PDF