• 대한화학회지
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• 제9권3호
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• pp.116-120
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• 1965

서울특별시 을지로 입구 네거리에서 1964년 8월 1일과 1965년 3월 6일에 대기의 오염도를 측정하였다. 자동차 폐가스로 오염되리라 생각되는 유해 가스 중 Pb, $SO_2,\;NO2,$ CO 및 $CO_2$의 농도를 측정하였다. 동시에 교통량도 조사하였다. Pb의 농도의 범위는 $21{\sim}2{\mu}./m^3, SO_2는\;0.33{\sim}0.001ppm$., $NO_2는\;1.30{\sim}0.02ppm$., CO는 $40{\sim}<5ppm$., $CO_2$는 $0.040{\sim}0.034%$였다. 평균농도는 Pb $11.3{\mu}./m^3., SO_2 0.08ppm, NO_2 0.09ppm., $NO 0.37ppm., CO 16ppm 그리고 0.038%였다. 일반적으로 Pb, NO2, NO, CO, $CO_2$의 농도는 교통량과 정비례하였다. 또 겨울 철에는 연탄 폐가스로 인해 $NO_2,SO_2 NO, CO, CO_2$의 농도가 여름 철보다 많았다.

• 한국자기학회지
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• 제9권6호
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• pp.312-320
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• 1999

RF 마그네트론 스퍼터링으로 제조한 SmCo/Cr 박막의 스퍼터 제조조건에 따르는 자기적 특성에 관하여 연구하였다. Sm 조성이 약 20 at %이고 Cr(50 nm)/SmCo(40 nm, 50W, 20mT)/Cr(150 nm, 100W, 30 mT)인 조건에서 제조한 시편에서 3.2 kOe의 최대 보자력을 얻었다. SmCo/Cr의 보자력은 하지층 표면거칠기와 SmCo의 조성에 크게 영향을 받았다. Cr 하지층의 거칠기는 Ar 분압과 두께가 증가할수록 증가하고 이는 SmCo 입자의 고립을 증가시켜 보자력이 증가된다. 본 SmCo 박막 증착시 사용한 RF 투입전력 및 Ar 분압은 SmCo의 조성을 변화시키며 최적의 조성(약 20 at.%Sm)에서 최대 보자력을 보인다. 또한 RF 파워 증가나 Ar 분압 증가에 의해 생긴 Cr 하지층의 표면거칠기, 치밀하지 않은 주상 계면구조등의 결함이 자구벽 이동을 방해하여 보자력 증가에 영향을 끼친다.

• 한국신재생에너지학회:학술대회논문집
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• 한국신재생에너지학회 2006년도 추계학술대회
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• pp.66-69
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• 2006

The idea of $CO_2$ sequestration in the ocean is proposed to be an effective mitigation strategy to counteract potential global warming due to the greenhouse effect Therefore, in the present study, calculations of the dissolution behavior of $CO_2$ hydrate when liquid carbon dioxide is released at 1,000m and 1,500m in depth are performed. The results show the liquid $CO_2$ injected in the ocean becomes $CO_2$ bubble at between 350m and 500m in depth, and the injection from a moving ship is a more effective method of dissolution than through a fixed pipeline. It so also noted that the ultimate plume generated from $CO_2$ bubbles repeats expansion and shrinking due to the peel ins from a fixed pipeline.

• 대한전기학회논문지
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• 제45권2호
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• pp.289-293
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• 1996

The basic study on laser triggered lightning was carried out for the active protection of lightning in power transmission system. The lengths of generated plasma channels were simulated numerically for variations of energy and pulse width of CO$_{2}$ laser by Runge-Kutta-Gill method. As results, the effective lengths of plasma channels were 2.3m, 2.67m and 3.4m respectively for energy of 45J, 60J and 100J of CO$_{2}$ laser pulse with pulse width of 50nsec using focusing mirror with focal length of 10m. And also the effects of pulse width of first pulse and tail pulse of CO$_{2}$ laser on the length of plasma channel were examined.

• Bulletin of the Korean Chemical Society
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• 제15권7호
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• pp.537-541
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• 1994

The reaction of the heterobimetallic anion, ${(OC)_5CrMn(CO)_5^-M^+ (M^+=Na^+, PPN^+)\;with\;CH_3I$ was proven to be overall 1st order with respect to $[(OC)_5CrMn(CO)_5^-]$ This reaction mechanism may be described in terms of the consecutive reaction pathway in which Cr$(CO)_5$(THF) may be an important intermediate, leading to the corresponding products such as MeMn$(CO)_5\;and\;ICr(CO)_5^-$, accordingly. The counterion effect on this reaction was also elucidated.

• Ocean and Polar Research
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• 제28권4호
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• pp.395-405
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• 2006

We measured the fugacity of $CO_2$ $(fCO_2)$, temperature, salinity, nutrients and chlorophyll a in the surface water of the western North Pacific $(4^{\circ}30'{\sim}33^{\circ}10'N,\;144^{\circ}20'{\sim}127^{\circ}35'E)$ in September 2002. There were zonally several major currents which have characteristics of specific temperature and salinity (NECC, North Equatorial Counter Current; NEC, North Equatorial Current; Kuroshio etc.). Surface $fCO_2$ distribution was clearly distinguished into two groups, tropical and subtropical areas of which boundary was $20^{\circ}N$. In the tropical Int surface $fCO_2$ was mainly controlled by temperature, while in the subtropical area, surface $fCO_2$ was dependent on total inorganic carbon contents. Air-sea $CO_2$ flux showed a large spatial variation, with a range of $-0.69{\sim}0.79 mmole\;m^{-2}day^{-1}$. In the area of AE (Anticyclonic Eddy), SM(Southern Mixed region) and NM (Northern Mixed region), the ocean acted as a weak source of $CO_2$ $(0.6{\sim}0.79 mmole\; m^{-2}day^{-1})$. In NECC, NEC, Kuroshio and ECS (East China Sea), however, the fluxes were estimated to be $-0.3mmole\; m^{-2}day^{-1})$ for the first three regions and $-1.2mmole\; m^{-2}day^{-1})$ for ECS respectively, indicating that these areas acted as sinks of $CO_2$. The average air-sea flux in the entire study area was $0.15mmole\;m^{-2}day^{-1})$, implying that the western North Pacific was a weak source of $CO_2$ during the study period.

• Ocean and Polar Research
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• 제30권3호
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• pp.335-345
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• 2008

In order to study spatial variabilities and major controlling factors, we measured fugacity of $CO_2(fCO_2)$, temperature, salinity and nutrients in surface waters of the North Pacific($7^{\circ}30'{\sim}33^{\circ}15'N$, $123^{\circ}56'E{\sim}164^{\circ}24'W$) between September$\sim$October 2007. The North Pacific and the marginal sea were distinguished by $fCO_2$ distribution as well as unique characteristics of temperature and salinity. There was a distinct diurnal SST variation in the tropical North Pacific area, and surface $fCO_2$ coincidently showed diurnal variation. In the North Pacific area, surface $fCO_2$ was mainly controlled by temperature, while in the marginal sea area it was primarily dependent on alkalinity and dissolved inorganic carbon concentrations. Air-sea $CO_2$ flux showed a large spatial variation, with a range of $-6.10{\sim}5.06\;mmol\;m^{-2}day^{-1}$. The center of subtropical gyre of North Pacific acted as a source of $CO_2(3.09{\pm}0.95\;mmol\;m^{-2}day^{-1})$. Tropical western North Pacific (i.e. the 'warm pool' area and the subtropical western North Pacific) acted as weak sources of $CO_2$($1.07{\pm}1.20\;mmol\;m^{-2}day^{-1}$ and $0.50{\pm}0.53\;mmol\;m^{-2}day^{-1}$, respectively). In the marginal sea, however, the flux was estimated to be $-0.68{\pm}1.17\;mmol\;m^{-2}day^{-1}$, indicating that this area acted as a sink for $CO_2$.

• 센서학회지
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• 제26권6호
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• pp.371-378
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• 2017

An accurate and robust estimation of center of rotation (CoR) using optical marker trajectory is crucial in human biomechanics. In this regard, the performances of the two prevailing least-squares methods, the Gamage and Lasenby (GL) method, and the Chang and Pollard (CP) method, are verified in this paper. While both methods are sphere-fitting approaches in closed form and require no tuning parameters, they have not been thoroughly verified by comparison of their estimation accuracies. Furthermore, while for both methods, results for stationary CoR locations are presented, cases for perturbed CoR locations have not been investigated for any of them. In this paper, the estimation performances of the GL method and CP method are investigated by varying the range of motion (RoM) and noise amount, for both stationary and perturbed CoR locations. The difference in the estimation performance according to the variation in the amount of noise and RoM was clearly shown for both methods. However, the CP method outperformed the GL method, as seen in results from both the simulated and the experimental data. Particularly, when the RoM is small, the GL method failed to estimate the appropriate CoR while the CP method reasonably maintained the accuracy. In addition, the CP method showed a considerably better predictability in CoR estimation for the perturbed CoR location data than the GL method. Accordingly, it may be concluded that the CP method is more suitable than the GL method for CoR estimation when RoM is limited and CoR location is perturbed.

• 대한화학회지
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• 제9권2호
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• pp.101-105
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• 1965

7-Nitroso-8-hydroxyquinoline-5-sulfonate(NHQS)는 pH 4.5에서 Co(Ⅱ)와 安定한 赤色 complex를 形成하므로 이것을 利用하여 NHQS에 依한 Co(Ⅱ)의 吸光光度定量方法을 檢討하였다. 吸光度는 528$m{\mu}$, $25^{\circ}C$에서 測定하였다. Co(Ⅱ)의 濃度 0.3∼6p.p.m에서 Beer의 法則은 成立하며 complex의 分子吸光係數는 $1.1{\times}10^4$이었다. 共存이온中 Fe(Ⅱ), Fe(Ⅲ), Cu(Ⅱ), Mn(Ⅱ), Hg(Ⅰ), CN-, EDTA 等은 本定量에서 妨害가 된다. Complex의 組成을 몰比法과 連續變化法으로 檢討한 結果 NHQS와 Co(Ⅱ)의 몰比는 3:1이었다.

• Bulletin of the Korean Chemical Society
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• 제11권2호
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• pp.109-114
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• 1990

The anionic transition metal hydrides $(HW(CO)_4P(OMe)_3\;^-,\;HW(CO)_5\;^-,\;HCr(CO)_5\;^-,\;HFe(CO)_4\;^-)$ react with transition metal alkyl $(CpMo(CO)_3(CH_3)$ to yield $CH_4\;and\;CH_3CHO$ in addition to the inorganic products $(CpMo(Co)_3\;^-$, etc.). The reaction of these anionic metal hydrides with CpMo(CO)3{CH2CH(CH2)2} may lead to an elucidation of the reaction mechanisms involved; the organic product distributions are among $CH_4,\;CH_2\;=\;CHCH_2CH_3$, and $CH_3CH(CH_2)_2$, depending upon the anionic metal hydride used. These anionic metal hydrides also are reported to undergo a hydride-halide exchange reaction with organic halides; therefore, these similar reactions have been compared in terms of leaving group ability $(CpMo(CO)_3\;^-\;vs.\;Br^-)$ and the mechanistic pathways.