• Journal of Bio-Environment Control
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• v.22 no.4
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• pp.361-365
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• 2013

To investigate factors determining peach fruit quality, chlorophyll content by leaf positions, chlorophyll content of foliated leaf, change of leaf area, and photosynthetic capacity were monitored. Photosynthetic rate in response to radiation intensity and $CO_2$ concentration, and change of sucrose content after shading treatment also were investigated. Chlorophyll content was similar in $5-12^{th}$ leaves after 10 days of foliation, while young $13-16^{th}$ leaves showed lower chlorophyll contents. Chlorophyll content was 2.56 ${\mu}g/cm^2$ on May $28^{th}$, just after foliation, and rapidly increased up to 6.35 ${\mu}g/cm^2$ on June $12^{th}$. After this point, chlorophyll content gradually increased during two months showing the highest value of 9.03 ${\mu}g/cm^2$ on August $14^{th}$. Leaf area was 27.1 $cm^2$ just after foliation and 37.7 $cm^2$ on $10^{th}$ day of foliation increasing 10.6 $cm^2$ during 10 days. Leaf area slowly increased by 3.9 $cm^2$ during next one month. Photosynthetic capacity increased rapidly until the $30^{th}$ day of foliation showing the highest capacity of 13.8 ${\mu}mol/m^{-2}/sec^{-1}$. After this point, photosynthetic capacity decreased sharply. Photosynthetic rate in response to radiation intensity increased rapidly until the PPFD reached to 600 ${\mu}mol/m^{-2}/sec^{-1}$ and increased gradually from 600 ${\mu}mol/m^{-2}/sec^{-1}$ to 1200 ${\mu}mol/m^{-2}/sec^{-1}$ of PPFD and stayed stable beyond this point. Photosynthetic rate in response to $CO_2$ concentration increased until 600 ppm of $CO_2$. At higher $CO_2$ concentration, photosynthetic rate stayed stable or decreased. Sucrose content in leaves was not significantly different between control and shading group until one hour of shading treatment while decreased in shading group after two hours of treatment.

• The Korean Journal of Nuclear Medicine Technology
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• v.16 no.1
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• pp.80-85
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• 2012

Purpose: The whole body bone scan is an examination that visualizing physiological change of bones and using bone-congenial radiopharmaceutical. The patients are intravenous injected radiopharmaceutical which labeled with radioactive isotope ($^{99m}Tc$) emitting 140 keV gammarays and scanned after injection. The 3 principles of radiation protection from external exposureare time, distance and shielding. On the 3 principles of radiation protection basis, radiopharmaceutical might just as well be injected rapidly for reducing radiation because it might be the unopened radiation source. However the radiopharmaceuticals are injected into patient directly and there is a limitation of distance control. This study confirmed the change of radiation exposure as change of distance from radiopharmaceutical and observed the change of radiation exposure afte rsetting a shelter for help to control radio-technician's exposure. Materials & methods: For calculate the average of injection time, the trained injector measured the injection time for 50 times and calculated the average (2 minutes). We made a source as filled the 99mTc-HDP 925 MBq 0.2 mL in a 1 mL syringe and measured the radiation exposure from 50 cm,100 cm,150 cm and 200 cm by using Geiger-Mueller counter (FH-40, Thermo Scientific, USA). Then we settled a lead shielding (lead equivalent 6 mm) from the source 25 cm distance and measured the radiation exposure from 50 cm distance. For verify the reproducibility, the measurement was done among 20 times. The correlation between before and after shielding was verified by using SPSS (ver. 18) as paired t-test. Results: The radiation doses according to distance during 2 minutes from the source without shielding were $1.986{\pm}0.052{\mu}$ Sv in 50 cm, $0.515{\pm}0.022{\mu}$ Sv in 100 cm, $0.251{\pm}0.012{\mu}$ Sv in 150 cm, $0.148{\pm}0.006{\mu}$ Sv in 200 cm. After setting the shielding, the radiation dose was $0.035{\pm}0.003{\mu}$ Sv. Therefore, there was a statistical significant difference between the radiation doses with shielding and without shielding ($p$<0.001). Conclusion: Because the great importance of whole body bone scan in the nuclear medicine, we should make an effort to reduce radiation exposure during radiopharmaceutical injections by referring the principles of radiation protection from external exposure. However there is a limitation of distance for direct injection and time for patients having attenuated tubules. We confirmed the reduction of radiation exposure by increasing distance. In case of setting shield from source 25 cm away, we confirmed reducing of radiation exposure. Therefore it would be better for reducing of radiation exposure to using shield during radiopharmaceutical injection.

• Applied Chemistry for Engineering
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• v.7 no.2
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• pp.362-370
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• 1996

The performance of The performance of $Li/V_6O_{13}$ cell and the electrochemical properties of polymer electrolyte based on poly(acrylonitrile)[PAN] was investigated. The ionic conductivity of polymer electrolyte showed $2.3{\times}10^{-3}S/cm$ and the compatibility with lithium electrode was excellent. Also, it showed the electrochemical stability up to 4.3V(vs. $Li^+/Li$). The cell reaction of $Li/V_6O_{13}$ was dominated by the interfacial resistance between $V_6O_{13}$ electrode and polymer electrolyte. The diffusion coefficient of lithium ion within $V_6O_{13}$ was $2.7{\times}10^{-9}{\sim}4.2{\times}10^{-8}cm^2/sec$. The utilization of $V_6O_{13}$ active material was 95% at C/8($50{\mu}A/cm^2$) and 82% at C/4($100{\mu}A/cm^2$), respectively.

• Mycobiology
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• v.37 no.1
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• pp.10-16
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• 2009

The purpose of this study is to understand spatio-temporal changes of active fungal biomass and water in Tricholoma matsutake soil colonies during the mushroom fruiting season. The active fungal biomass was estimated by analyzing ergosterol content at four different points within four replicated locations in a single circular T. matsutake colony at Ssanggok valley in the Sogri Mt. National Park in Korea during 2003 to 2005. The four points were the ahead of the colony, the front edge of the colony and 20 cm and 40 cm back from the front edge of the colony. Ergosterol content was 0.0 to 0.7 ${\mu}g$ per gram dried soil at the ahead, 2.5 to 4.8 ${\mu}g$ at the front edge, 0.5 to 1.8 ${\mu}g$ at the 20 cm back and 0.3 to 0.8 ${\mu}g$ at the 40 cm back. The ergosterol content was very high at the front edge where the T. matsutake hyphae were most active. However, ergosterol content did not significantly change during the fruiting season, September to October. Soil water contents were lower at the front edge and 20 cm back from the front edge of the colony than at the ahead and 40 cm back during the fruiting season. Soil water content ranged from 12 to 19% at the ahead, 10 to 11% at the edge, 9 to 11% at the 20 cm back and 11 to 15% at the 40 cm back. Our results suggest that the active front edge of the T. matsutake soil colony could be managed in terms of water relation and T. matsutake ectomycorrhizal root development.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.9 no.3
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• pp.576-581
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• 2005

In this paper. the a-Si:H TFT using ferroelectric of $SrTiO_3$ as a gate insulator is fabricated on glass. High k gate dielectric is required for on-current, threshold voltage and breakdown characteristics of TFT Dielectric characteristics of ferroelectric are superior to $SiO_2$ and $Si_3N_4$. Ferroelectric increases on-current and decreases threshold voltage of TFT and also ran improve breakdown characteristics.$SrTiO_4$ thin film is deposited by e-beam evaporation. Deposited films are annealed for 1 hour in N2 ambient at $150^{\circ}C\~600^{\circ}C$. Dielectric constant of ferroelectric is about 60-100 and breakdown field is about IMV/cm. In this paper, the TFT using ferroelectric consisted of double layer gate insulator to minimize the leakage current. a-SiN:H, a-Si:H (n-type a-Si:H) are deposited onto $SrTiO_3$ film to make MFNS(Metal/ferroelectric/a-SiN:H/a-Si:H) by PECVD. In this paper, TFR using ferroelectric has channel length of$8~20{\mu}m$ and channel width of $80~200{\mu}m$. And it shows that drain current is $3.4{\mu}A$at 20 gate voltage, $I_{on}/I_{off}$ is a ratio of $10^5\~10^8,\;and\;V_{th}$ is$4\~5\;volts$, respectively. In the case of TFT without having ferroelectric, it indicates that the drain current is $1.5{\mu}A$ at 20gate voltage and $V_{th}$ is $5\~6$ volts. If properties of the ferroelectric thin film are improved, the performance of TFT using this ferroelectric thin film can be advanced.

• Journal of Bio-Environment Control
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• v.7 no.4
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• pp.298-310
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• 1998

This research was carried out to find out spray characteristics of 3 types of spray nozzle to be used for greenhouse cooling. Following results were obtained from this experimental study. Water amounts sprayed with each nozzle were increased with the spraying pressure. However the increment of sprayed amount with the increase of spraying pressure were not consistent regardless of nozzle types. For the whole tested spraying pressures of nozzle-type I, II, III, the minimum droplet sizes were about 1.7~2.5$\mu$m, 1.7~2.2$\mu$m and 1.7~2.2$\mu$m, respectively, and the maximum droplet sizes were about 44~60$\mu$m, 52~71$\mu$m and 45~61$\mu$m, respectively, and the average droplet sizes were about 23~38$\mu$m, 19~24$\mu$m and 17~25$\mu$m, respectively The most appropriate spraying pressures of nozzle-type I, II, III were analyzed to be 70kgf/$\textrm{cm}^2$, 30kgf/$\textrm{cm}^2$ and 30kgf/$\textrm{cm}^2$, respectively, and their sprayed amounts were about 124mL/min, 103mL/min and 84mL/min, respectively, and average droplet sizes were 22.6$\mu$m, 21.8$\mu$m and 20.6$\mu$m, respectively. Also, with the order of nozzle-type I, II, III, droplet size distributions less than 30$\mu$m were 95.4%, 85.7% and 79.0%, respectively, and the distributions larger than 40$\mu$m were 0.2%, 1.28% and 1.67%, respectively. However most all of the droplet size were less than 50$\mu$m.

• Proceedings of the Korean Vacuum Society Conference
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• 2012.02a
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• pp.308-308
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• 2012

현재 결정질 태양전지 제작에 있어 공정 단가 및 재료비 절감을 위해 실리콘 웨이퍼의 두께가 점점 얇아지는 추세이며, 이에 따른 장파장 영역 흡수 손실을 감소시키기 위한 방안으로 후면 패시베이션에 관한 연구가 활발히 진행되고 있다. 후면 패시베이션층으로는 SiO2, SiNx, a-Si:H, SiOxNy 등의 물질이 사용되고 있으며, 본 연구에서는 SiO2/SiNx/SiO2 (ONO)의 삼중막 구조를 패시베이션층으로 하여 SiNx 단일막 구조와의 열처리 온도에 따른 소수캐리어 수명(${\tau}eff$), 후면 재결합속도(Seff), 확산거리(LD) 등의 파라미터 변화를 비교하였다. 증착 직후와 $350^{\circ}C$에서의 Forming Gas Annealing (FGA), 그리고 $800^{\circ}C$의 고온에서의 fast firing 후의 각각의 파라미터 변화를 관찰하였다. 증착 직후 SiNx 단일막과 ONO 삼중막의 소수캐리어 수명은 각각 $108{\mu}s$와 $145{\mu}s$를 보였다. 후면 재결합속도는 65 cm/s와 44 cm/s를 보였으며, 확산거리는 각각 $560{\mu}m$와 $640{\mu}m$를 나타내었다. FGA와 firing 열처리 후 세 파마미터는 모두 향상된 값을 보였으며 최종 firing 처리 후 단일막과 삼중막의 소수캐리어 수명은 각각 $196{\mu}s$와 $212{\mu}s$를 보였다. 또한 후면 재결합속도는 28 cm/s와 24 cm/s를 보였으며, 확산거리는 각각 $750{\mu}m$와 $780{\mu}m$를 보여 ONO 삼중막 구조의 경우에서 보다 우수한 특성을 보였다. 본 실험을 통해 SiNx 단일막보다 ONO 패시베이션 구조에서의 열적안정성이 우수함을 확인하였으며, 또한 ONO 패시베이션 구조는 열적 안정성뿐 아니라 n-type 도핑을 위한 Back To Back (BTB) 도핑 공정 시 후면으로 의 도펀트 침투를 막는 차단 층으로서의 역할도 기대할 수 있다.

• KSBB Journal
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• v.11 no.4
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• pp.504-509
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• 1996

Promoters which are useful for constructing expression vectors for lactic acid bacteria were obtained from the chromosomal DNA of Lactococcus lactis ssp. lactis MG1363. pBV5030, a promoter-selection vector, replicates in L. lactis and Escherichia coli and carries a promoterless chloramphenicol acetyltransferase gene (cat-86). After examining E. coli transformants which grew on LB media containing chloramphenicol (Cm, 20$\mu\textrm{g}$/mL) , many MG1363 derived DNA fragments which encompass promoter sequences were identified. Some recombinant E. coli cells can grow at the Cm concentration of 1,000$\mu\textrm{g}$/mL. When plasmids from those highly resistant E. coli cells were purified and introduced into L. lactis ssp. lactis MG1614 cells by electroporation, lactococcal transformants showing Cm resistance were obtained. So far, five plasmids with different promoter inserts were introduced into L. lactis MGl614 cells. The maximum level of Cm resistance in L. lactis MG1614 transformants was quite low (20$\mu\textrm{g}$/mL) when compared with that observed in recombinant E. coli cells harboring the same plasmids.

• Journal of the Microelectronics and Packaging Society
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• v.12 no.3 s.36
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• pp.253-258
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• 2005

Characteristics of electroplated Ni films such as grain size, resistivity, solder wetting angle, and growth rate of intermetallic compound were evaluated as a function of electroplating current density. With increasing the electroplating current density from $5\;mA/cm^2 $ to $40\;mA/cm^2 $, the nodule size on the Ni film surface decreased, grain refinement occurred, and resistivity increased from $7.37\mu\Omega-cm$ to $9.13\mu\Omega-cm$. Compared with Ni film processed at $40\;mA/cm^2 $, Ni films electroplated at $5\;mA/cm^2 $ and $10\;mA/cm^2 $ exhibited low resistivity, dense microstructure, and slow growth rate of intermetallic compound. Ni films electroplated at $5\;mA/cm^2 $ and $10\;mA/cm^2 $ are more suitable for Ni UBM application than that fabricated at $40\;mA/cm^2 $.

• Korean Journal of Agricultural Science
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• v.22 no.2
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• pp.151-155
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• 1995

Two types of modified celluloses which contain trinitrophenyl groups as chromophore were synthesized from carboxymethyl cellulose Whatman CM 70 and CM 32. Diaminoethyl groups were added to the CM 70 and CM 32 to make DAE-CM celluloses and then the DAE-CM groups were substituted by 2,4,6-trinitrophenyl groups to produce TNP-celluloses. Average particle size of the TNP-cellulose from CM 32 was $44.6{\pm}9.6{\mu}m$ in diameter and $127.9{\pm}22.5{\mu}m$ in length, which was much smaller than those from CM 70, however its TNP-moiety per gram determined by using the molar extinction coefficient $1.33{\times}10^4$ of ${\varepsilon}$-TNP-lysine at 345 nm, was 0.68 millimoles, which was 5.6-fold greater than those from CM 70. The absorption spectrum of TNP-oligosaccharides which were the soluble products of TNP-celluloses by a cellulase preparation Onozuka R-10, showed a maximal peak at 344 nm. Increases in the absorbance during hydrolysis were linear with the enzyme concentration, and the differences of slope values between two types of TNP-celluloses that the more semsitive assay could be achieved by using those from CM 32 as substrate at the low range of the enzyme concentration.