• Journal of the Korean Academy of Child and Adolescent Psychiatry
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• 제16권2호
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• pp.153-159
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• 2005

본 고에서는 지금까지 자폐 장애 및 PDD에서 행해졌던 신경발달학적 병리 소견들에 대하여 살펴보고자 하였다. 자폐 장애에서 전형적으로 관찰되는 신경병리학적 소견들은 소뇌에서의 Purkinje 세포 수의 감소, 변연계에서의 증가된 세포 밀도 및 축소된 신경원 크기, 피질의 이형성 및 이동 장애 등이라고 할 수 있겠다. 그러나, 일부 문헌들은 일관되고 일치된 결과를 보인 반면, 대부분의 연구결과들이 아직까지는 불확실한 상태로 남아있다. 이것은 매우 적은 대상군과 자폐 장애의 이질성(heterogeneity), 기타 공존 질환 통제의 어려움, 연구 디자인의 비정교성에 기인한 통계량의 부족과 관련이 있다. 따라서 향후 좀더 정교한 디자인에 의하여 자폐 환자 대상군을 많이 확보하여 다양한 혼란 변인들을 통제한 후 신경발달학적 소견들을 연구한다면 자폐 장애의 원인론을 확립하는데 많은 공헌을 할것으로 기대된다.

• 한국진공학회:학술대회논문집
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• 한국진공학회 2016년도 제50회 동계 정기학술대회 초록집
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• pp.306.1-306.1
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• 2016

ZnO semiconductor material has been widely utilized in various applications in semiconductor device technology owing to its unique electrical and optical features. It is a promising as solar cell material, because of its low cost, n-type conductivity and wide direct band gap. In this work ZnO/Si heterojunctions were fabricated by using pulsed laser deposition. Vacuum chamber was evacuated to a base pressure of approximately $2{\times}10^{-6}Torr$. ZnO thin films were grown on p-Si (100) substrate at oxygen partial pressure from 5mTorr to 40mTorr. Growth temperature of ZnO thin films was set to 773K. A pulsed (10 Hz) Nd:YAG laser operating at a wavelength of 266 nm was used to produce a plasma plume from an ablated a ZnO target, whose density of laser energy was $10J/cm^2$. Thickness of all the thin films of ZnO was about 300nm. The optical property was characterized by photoluminescence and crystallinity of ZnO was analyzed by X-ray diffraction. For fabrication ZnO/Si heterojunction diodes, indium metal and Al grid patterns were deposited on back and front side of the solar cells by using thermal evaporator, respectively. Finally, current-voltage characteristics of the ZnO/Si structure were studied by using Keithly 2600. Under Air Mass 1.5 Global solar simulator with an irradiation intensity of $100mW/cm^2$, the electrical properties of ZnO/Si heterojunction photovoltaic devices were analyzed.

• Asian-Australasian Journal of Animal Sciences
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• 제12권1호
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• pp.129-138
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• 1999

If rumen bacteria can be manipulated to utilize nutrients (i.e., ammonia and plant cell wall carbohydrates) more completely and efficiently, the need for protein supplementation can be reduced or eliminated and the digestion of fiber in forage or agricultural residue-based diets could be enhanced. However, these approaches require a complete and accurate description of the rumen community, as well as methods for the rapid and accurate detection of microbial density, diversity, phylogeny, and gene expression. Molecular ecology techniques based on small subunit (SSU) rRNA sequences, nucleic acid probes and the polymerase chain reaction (PCR) can potentially provide a complete description of the microbial ecology of the rumen of ruminant animals. The development of these molecular tools will result in greater insights into community structure and activity of gut microbial ecosystems in relation to functional interactions between different bacteria, spatial and temporal relationships between different microorganisms and between microorganisms and reed panicles. Molecular approaches based on SSU rRNA serve to evaluate the presence of specific sequences in the community and provide a link between knowledge obtained from pure cultures and the microbial populations they represent in the rumen. The successful development and application of these methods promises to provide opportunities to link distribution and identity of gastrointestinal microbes in their natural environment with their genetic potential and in situ activities. The use of approaches for assessing pupulation dynamics as well as for assessing community functionality will result in an increased understanding and a complete description of the gastrointestinal communities of production animals fed under different dietary regimes, and lead to new strategies for improving animal growth.

• Korean Chemical Engineering Research
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• 제56권4호
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• pp.447-452
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• 2018

HF, NaF, $NH_4F$와 같이 플루오르 이온(F-)이 함유된 전해질에서 티타늄 금속판을 양극산화시켜 $0.34{\mu}m$부터 최대 $8.9{\mu}m$까지 다양한 길이의 티타니아 나노튜브(TNT)를 제조하였다. 양극산화에 의해 제조된 TNT를 $450^{\circ}C$에서 소성시키면 광 활성을 가지는 아나타제 결정이 생성되었다. TNT 기반 염료감응 태양전지(DSSC)는 TNT 길이가 $2.5{\mu}m$일때 광전환 효율이 4.71%로 최대를 나타내었다. 이 값은 티타니아 페이스트를 코팅하여 제작한 FTO 기반 DSSC의 광전환 효율 보다 약 18% 높았다. 또한 TNT-DSSC의 단락전류밀도($J_{sc}$)는 $9.74mA/cm^2$로 FTO-DSSC의 $7.19mA/cm^2$ 보다 약 35% 이상 높았다. TNT-DSSC 태양전지의 광전환 효율이 더 높은 이유는 염료에서 생성된 광전자가 TNT를 통해 전극 표면으로 빨리 전달되어 광전자와 염료가 재결합 되는 것이 억제되었기 때문이다.

• 대한토목학회논문집
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• 제35권6호
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• pp.1219-1228
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• 2015

면적고정형 ARF (Fixed Area ARFs)방법은 강우관측소의 지점강우를 활용하여 산정되고 있으며, 공간적 관측밀도의 제약이 정확한 ARF산정에 제약조건이 되고 있다. 본 연구에서는 레이더 강우관측을 활용하여 호우중심형의 ARF를 제시하고자 한다. 호우중심형 ARF (Storm-centered ARFs)산정 시 강우의 이동성, 방향성, 공간분포를 고려하기 위하여 강우사상별 강우형상에 따른 타원 장축의 방향성 결정, 강우형상에 따른 면적별 최적면적강우량을 산정하여 ARF를 제시하였다. 전선형에 비하여 태풍의 ARF값의 변동 폭이 작은 것을 알 수 있었고, 전선형은 지속시간에 따라 ARF가 증가하지만, 태풍의 경우에는 오히려 ARF가 감소하는 모습을 볼 수 있었다. 이 결과 지속시간이 비교적 짧은 1~3시간에서는 태풍 산바 사상의 ARF가 크게 산정되었으나, 지속시간이 긴 6~24시간에서는 ARF가 전선형 강우에 비해 작게 산정됨을 확인하였다.

• 한국진공학회:학술대회논문집
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• 한국진공학회 2015년도 제49회 하계 정기학술대회 초록집
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• pp.236.1-236.1
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• 2015

The surface morphology of front transparent conductive oxide (TCO) films is very important to achieve high current density in amorphous silicon (a-Si) thin film solar cells since it can scatter the light in a better way. In this study, we present the low cost hydrothermal deposited uniform zinc oxide (ZnO) nano-flower structure with various aspect ratios for a-Si thin film solar cells. The ZnO nano-flower structures with various aspect ratios were grown on the RF magnetron sputtered AZO films. The diameters and length of the ZnO nano-flowers was controlled by varying the annealing time. The length of ZnO nano-flowers were varied from 400 nm to $2{\mu}m$ while diameter was kept higher than 200 nm to obtain different aspect ratios. The ZnO nano-flowers with higher surface area as compared to conventional ZnO nano structure are preferred for the better light scattering. The conductivity and crystallinity of ZnO nano-flowers can be enhanced by annealing in hydrogen atmosphere at 350 oC. The vertical aligned ZnO nano-flowers showed higher haze ratio as compared to the commercially available FTO films. We also observed that the scattering in the longer wavelength region was favored for the high aspect ratio of ZnO nano-flowers. Therefore, we proposed low cost and vertically aligned ZnO nano-flowers for the high performance of thin film solar cells.

• KSBB Journal
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• 제16권3호
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• pp.281-285
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• 2001

실험실 규모의 생불여과기에 peat들 패깅하여 휘발성 유기 화합물 (isoprene, dimethyl 야dfide, 블로르포륨, 벤젠, 삼염화에 헬렌, 툴루엔. m-자일렌. 0-자일렌, 스타이렌)의 분해 정도를 가스 처l류시간을 3.2분으로 하여 80일간 측정하였다. 34일의 적응기간이 지난 후 $65~83 g/m^3$로 유입되는 VOC의 분해율 이 $25^{circ}C$액서는 93%이었으나 $45^{circ}C$에서는 여 보다 낮은 73%이었다. $25^{circ}C$에서 77일 후 도달한 최고 세포농도논 초기 농도 의 약 100배인 $1.12\times10^8$세포/g 이었다, 그러나 $45^{circ}C$C에서 도 달한 최고 세포농도는 이의 10분의 1에 불과하였다. m-자이렌과 툴루엔의 분해율 (91 %)에 비하여 벤젠의 분해율 (86%)이 낮았다. 생불여과기의 패정된 부분을 네 구간으로 나누었 을 때 가스가 유입되는 저음 사분회 일에 해당하는 부분에서 VOC의 분해율이 60%에 도달하였다 본 연구는 휘발생 유해 물질 혼합처l를 생붙여과법에 의해 처리하는 것이 가능함을 보여주었고 이러한 기술을 현장에서 배출되는 대기유해풀 칠의 효율적 저감에 적용하면 대기보첸에 기여할 수 있을 것이다.

• Biomolecules & Therapeutics
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• 제1권2호
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• pp.131-136
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• 1993

In the present study, the effect of $HgCl_2$on the function of human peripheral polymorphonuclear leukocytes(PMNs) was examined. PMNs were isolated from human peripheral blood with density centrifugation in Ficoll-Paque. The cells were then incubated with $0.5{\sim}5{\mu}M\;HgCl_2$and glass adherence, chemotactic activity and erythrocyte-antibody rosette forming activity were measured. $HgCl_2$ decreased the function of PMNs in all three aspects tested. $HgCl_2$significantly diminished glass adherence(40.5 {\mu}M: 92{\pm}12%$ (percentage of control, $mean{\pm}$ S.D.); 41 {\mu}M: 46{\pm}11%,$ P<0.01; $3{\mu}M: 35{\pm}7%,$P<0.01;$5{\mu}M:49{\pm}10%,$ P<0.01). Similarly, significant differences were observed in chemotactic activity after $HgCl_2$treatment compared with control (control: $0.95{\pm}0.14mm; 0.5 {\mu}M: 0.91{\pm}0.11 mm; 1 {\mu}M: 0.77{\pm}0.16mm, P<0.05; 3{\mu}M: 0.61{\pm} 0.06mm, P<0.01; 5{\mu}M: 0.15{\pm}0.03 mm, P<0.01).$ Also, 4HgCl_2$decreased the percentage of rosette-forming PMNs, indicating diminished phagocytic activity of PMNs upon $HgCl_2$ exposure compared with control (control: $58{\pm}4%; 1{\mu}M: 53{\pm}4%, p<0.05; 3{\mu}M: 49{\pm}3%, P<0.01; 5{\mu}M: 46{\pm}3%, P<0.01).$ Cell viability was not antered after $HgCl_2$treatment (483{\pm}5%$ viability in control PMNs versus $81{\pm}8%$ viability in $5{\mu}M$ Hg-treated PMNs), suggesting that the impaired PMN function after $HgCl_2$treatment was not due to nonspecific cytotoxicity induced by $HgCl_2$. $HgCl_2$-induced decrease in the function of PMNs may have some implications in depressed host susceptibilityupon bacterial challenge after mercury exposure.

• Journal of Acupuncture Research
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• 제24권3호
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• pp.81-97
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• 2007

Objectives: The purpose of this study is to investigate the anti-oxidative effect of electroacupuncture at Kokchi($LI_{11}$) in rats. Methods: A study administer AAPH to the abdominal cavity of rats and stimulate Kokchi($LI_{11}$) of the rat that lead to oxidative stress by electropuncture. And the study survey serum albumin, total bilirubin, LDL-cholesterol, LDH, Glucose, GOT, GPT and measure SOD activity, GSH concentration, catalase activity, NO concentration, MDA concentration. Results: 1. At the analysis of blood chemistry Albumin and Glucose significantly increase at $LI_{11}$-NR group, $LI_{11}$-EA group than at control group and holder group. LDL cholesterol, GOT, GPT decrease meaningfully. 2. As results of measurement at liver, SOD, Catalase represnet significantly increase at $LI_{11}$-NR group and $LI_{11}$-EA group than at control group and holder group. 3. Glutathione has some increases at the $LI_{11}$-NR group and $LI_{11}$-EA group than at the control group and the holder group. 4. As a result of measurement of NO and MDA's content, the content of NO decrease at the $LI_{11}$-NR group than at the control group. That reduces more meaningfully at the $LI_{11}$-EA group than at the control group. MDA has a significant decrease at the $LI_{11}$-NR group and the $LI_{11}$-EA group. 5. At the histological analysis, the study confirm that the density of intracellular cytoplasm in the liver tissue decreases at the control group as compared with the Normal group and the size of cell increases. Conclusions : These results suppose that electroacupuncture at $LI_{11}$ has an anti-oxidant effect in human.

• 한국세라믹학회지
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• 제43권2호
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• pp.121-125
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• 2006

[ $LiFePO_4$ ] is one of the promising materials for cathode material of secondary lithium batteries due to its high energy density, low cost, environmental friendliness and safety. $LiFePO_4$ was synthesized by the solid-state reaction method at 500 - 800°C. The crystal structure of $LiFePO_4$ was analyzed by X-ray powder diffraction. The samples synthesized at 600 and $700^{\circ}C$ showed a single phase of a olivine structure. The particle sizes were increased and the specific surface areas were decreased with heating temperatures. The electrochemical performance was investigated by coin cell test. The discharge capacities at 0.1 C-rate were 118 mAh/g and 112 mAh/g at $600^{\circ}C,\;700^{\circ}C$, respectively. In an attempt to improve the electrical conductivity of cathode materials, $LiFePO_4/graphite$ composite was prepared with various graphite contents. The electrical conductivity and discharge capacity were increased with increasing the graphite contents in composite samples. The rate capabilities at high current densities were also improved.