• Applied Microscopy
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• 제25권4호
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• pp.124-131
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• 1995

이상과 같은 실험결과를 다음과 같은 요약할 수 있다. 1) $Hg_{1-x}\;Tl_{x}\;Ba_{2}(Ca_{0.86}\;Sr_{0.14})_{2}\;Cu_{3}\;O_{8+\delta}$의 구조는 Hg-1223과 같은 구조를 이루며 Hg 위치에 T1이 치환되어 있음을 알 수 있다. 2) 격자상수는 탈륨이 증가할수록 감소하는 경향을 나타냈으나 x=0.25 시료에서는 현저히 감소됨을 보였다. 3) x=0.25 시료에서는 적층 결함 1234구조가 1223구조와 intergrowth함을 보였고 불순물 상이 다소 나타났다. 4) 탈륨이 증가할 수록 보다 치밀하고 결함이 없는 안정된 조직을 보였다. 5) 모든 시료가 관찰 도중 전자빔에 대하여 손상되었으나 탈륨의 양이 증가할 수록 손상에 대한 저항이 커져 보다 안정된 상을 보였다.

• Mass Spectrometry Letters
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• 제3권2호
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• pp.58-61
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• 2012

A method based on flow injection-isotope dilution-cold vapor-inductively coupled plasma mass spectrometry (FI-IDCV-ICP/MS) has been applied to determine trace level of mercury in fly ash. $^{200}Hg$ isotopic spike was added to 0.25 g of BCR176R fly ash and then decomposed by microwave digestion procedure with acid mixture A (8 mL $HNO_3$ + 2 mL HCl + 2 mL HF) and acid mixture B (8 mL $HNO_3$ + 2 mL $HClO_4$ + 2 mL HF) for applying IDMS. Mercury cold vapor was generated by using reductant solution of 0.2% (w/w) $NaBH_4$ and 0.05% (w/w) NaOH. The measurements of n($^{200}Hg$)/n($^{202}Hg$) isotope ratio was made using a quadrupole ICP/MS system. The accuracy in this method was verified by the analysis of certified reference material (CRM) of fly ash (BCR 176R). The indicative value of Hg in BCR 176R fly ash was $1.60{\pm}0.23$ mg/kg (k = 2). The determined values of Hg in BCR 176R fly ash by the method of FI-CV-ID-ICP/MS described in this paper were $1.60{\pm}0.24$ mg/kg (k = 3.18) and the analysis results were in well agreement with the indicative value within the range of uncertainty.

• Journal of Chest Surgery
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• 제22권2호
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• pp.179-190
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• 1989

The experimental study for extracorporeal preservation of the heart-lung preparation by autoperfusion system was performed in 10 dogs. Under intravenous Pentothal endotracheal anesthesia bilateral thoracotomies were performed. A 24F cannula connected to a plastic reservoir bag located 100 cm above the level of the heart was introduced into the aortic arch. Left subclavian, innominate artery, and descending aorta were ligated and divided. Both vena cavae were ligated and divided after the bag was half filled with blood. A 24F catheter inserted into right atrium and connected to the plastic bag in order to keep constant the preload. The thoracic trachea was intubated and the lungs were ventilated. The heart-lung preparations were removed en bloc and floated in a $34^{\circ}C$ bath of Hartmann solution. The preparations were observed for from 2 hours to 8 hours, with the average of 5.2 hours. Hemodynamic and hematologic variables were measured during preharvest and autoperfusion. The pH revealed severe respiratory alkalosis due to very low $PaCO_2$ during autoperfusion ; $PaO_2$ remained constant for 130-140 mmHg; $A-aDO_2$ increased markedly. The static inspiratory pressure [SIP] at late autoperfusion [6hr] increased significantly as compared with at early autoperfusion [2hr]. There was no difference between white blood cell counts from right atrium and those of left atrium. Heart rates remained constant for 110-120/min; cardiac outputs maintained to approximately 0.6L/min; mean aortic pressures, 75 mmHg; mean pulmonary arterial pressures, 15-18 mmHg; mean right atrial pressures, 9-13 mmHg; mean left atrial pressures, 12 mmHg lower than those of right atrium. Serum Na maintained with normal range during autoperfusion; K increased significantly; Ca decreased progressively. Hemoglobin and hematocrit decreased significantly during autoperfusion. The study demonstrated that stable hemodynamics could be maintained throughout the experiment and the preparation of the lung seemed to be inadequate, especially after 3-4 hours, such as high $A-aDO_2$, increased SIP, and scattered atelectasis and edema in their gross appearances.

• 대한화학회지
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• 제37권11호
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• pp.951-960
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• 1993

수용액상에서 $Hg^{2+}$에 의한 trans-[Co(3,2,3-tet)$X_2]^+$ (3,2,3-tet = 4,7-diazadecane-1,10-diamine, $X_2\;=\;Cl_2,\;(NO_2)Cl,\;Br_2,\;(NO_2)Br,\;(NO_3)_2)$ 착물의 아쿠아 반응이 연구되었다. 생성물을 확인하고 반응메카니즘을 추정하기 위하여 크로마토그래피를 사용하였고 전자흡수 스펙트럼을 측정하였다. 그 결과 네자리 리간드인 3,2,3-tet가 배위된 여러가지 $trans-[Co(3,2,3-tet)X_2]^+$ 착물은 각각 아쿠아된 trans-[Co(3,2,3-tet)$(OH_2)_2]^{3+}$ 착물을 거쳐 cis-${\beta}$-[Co(3,2,3-tet)$(OH_2)_2]^{3+}$ 착물이 생성되었다. $Hg^{2+}$에 의한 trans-$[Co(3,2,3-tet)Cl_2]^+$ 착물과 trans-[Co(3,2,3-tet)$(NO_2)Cl]^+$ 착물의 아쿠아 반응에 대한 메카니즘을 추정하기 위하여 속도론적 조사를 하였따. 그 결과 $trans-[Co(3,2,3-tet)Cl_2]^+$ 착물은 D(dissociative)-메카니즘으로 진행되었고, trans-[Co(3,2,3-tet)$(NO2_)Cl]^+ $착물은 $I_d$(interchange dissociative)-메카니즘으로 진행되었다. 그리고 입체화학적인 거동을 조사하기 위하여 라세미(R,R:S,S)3,2,3-tet 대신에 키랄성이 R,R인 3,2,3,-tet를 배위시킨 trans-$[Co(R,R-3,2,3-tet)Cl_2]^+$ 착물에 $Hg^{2+}$를 용리시켰을 때 아쿠아 반응에 대한 원편광이색성(circular dichroism) 스펙트럼을 측정하여 그 절대구조를 확인한 결과 ${\Delta}-cis-{\beta}$-[Co(R,R-3,2,3-tet)$(OH_2)_2]^{3+}$ 착물이 생성되었다.

• Korean Chemical Engineering Research
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• 제57권2호
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• pp.289-300
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• 2019

We have conducted a preliminary numerical analysis to understand the effects of double-diffusive convection on the molar flux at the crystal region during the growth of mercurous bromide ($Hg_2Br_2$) crystals in 1 g and microgravity (${\mu}g$) conditions. It was found that the total molar fluxes decay first-order exponentially with the aspect ratio (AR, transport length-to-width), $1{\leq}AR{\leq}10$. With increasing the aspect ratio of the horizontal enclosure from AR = 1 up to Ar = 10, the convection flow field shifts to the advective-diffusion mode and the flow structures become stable. Therefore, altering the aspect ratio of the enclosure allows one to control the effect of the double diffusive natural convection. Moreover, microgravity environments less than $10^{-2}g$ make the effect of double-diffusive natural convection much reduced so that the convection mode could be switched over the advective-diffusion mode.

• Journal of Chest Surgery
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• 제17권4호
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• pp.666-671
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• 1984

During a fire-year period from March 1979 to February 1984, 559 patients underwent surgical treatment for rheumatic mitral valve disease at Seoul National University Hospital. Left atrial thrombus was found at surgery in 74 of these patients, an incidence of 13.2%. This report outlines the surgical experience with these seventy-four patients. They were 32 men and 42 women, and their age ranged between 23 and 57 with mean of 42 years old. All except one had the findings of atrial fibrillation on the preoperative electrocardiogram. Ten [13.5%] had experienced embolic events before surgery. A history of one or more episodes of cardiac failure requiring digitalis and diuretics was noted in all patients Nineteen were associated with the aortic and/or tricuspid valve disease and closed mitral commissurotomy had been performed previously in four patients. The average cardiac index was 2.68L/min/M2 [1.59 to 3.47 L/min/M2] The mean systolic pulmonary artery pressure was 57mmHg [26 to 120 mmHg]and pulmonary capillary wedge pressure 21.5 mmHg [12 to 40 mmHg]. There were no significant hemodynamic findings to suggest the presence of the left atrial thrombus. Operative mortality was acceptable with two early deaths [2.7%]. The follow-up of the hospital survivors has shown excellent functional status.

• 한국지하수토양환경학회지:지하수토양환경
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• 제21권3호
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• pp.1-5
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• 2016

Rhodamine B Hydrazide as a novel fluorescent and colorimetric probe exhibiting remarkably selective fluorescence enhancement toward Hg²⁺ ion over other 16 metal ions is herein introduced. The probe reacts with Hg²⁺ ion followed by its spirolactam ring-opening to give a remarkable enhancement of absorption maximum at 550 nm as well as an enhanced fluorescence intensity at 580 nm in aqueous media. Upon titration with Hg²⁺ ion in various concentration of 10~200 uM, we found that the probe shows a marked color change from colorless to pink, enabling naked-eye detection toward mercury ion. In addition, in the presence of Hg²⁺ ion, the probe gave rise to change from non-florescence to strong orange fluorescence (Off-On) with a good linearity of R²=0.97. This preliminary results demonstrate that the fluorescent chemosensor we herein introduced can open a new strategy for marked selective and sensitive detection of mercury ions in contaminated soil containing various metal ions.

• 대한화학회지
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• 제36권2호
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• pp.223-229
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• 1992

정사면체 구조를 갖는 $SpCuCl_2$와 수은(II) 이온 및 수은 금속간의 금속 교환반응의 속도론적인 연구를 순환 전압전류법과 자외 가시선 분광법을 사용하여 실험하였다. 수은(II) 이온 및 수은 금속과$SpCuCl_2$와의 교환 반응은 유사일차속도식을 따른다. 교환반응의 속도상수와 활성화 계수들의 값을 구하고 이들을 정리하여 나타내었다. 이러한 실험결과들로부터 Sp 배위자에 동시에 결합되어 있는 구리와 수은의 이핵 착물에서 구리와 질소간의 결합이 끊어지는 과정이 교환반응의 속도결정단계임을 알 수 있다.

• Journal of Chest Surgery
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• 제40권3호
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• pp.193-199
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• 2007

배경: 저자들은 라스텔리 수술(Rastelli operation) 후 도관협착을 해결하기 위해 협착된 도관을 제거한 후 그 후벽을 자가조직으로 이용하고 판막을 삽입한 후 전벽을 인공 첩포로 덮는 peel 수술을 시행하여 왔다. 이 수술의 결과를 후향적으로 조사하였다. 대상 및 방법: 2002년 5월부터 2006년 7월까지 모두 9명의 심외도관 협착 환자에서 peel 수술을 시행하였다. 라스텔리 수술 후 평균 $5.1{\pm}1.7$년 후 재수술을 하게 되었으며 peel 수술 시 환아의 평균 나이는 $7.5{\pm}2.4$년(범위: $2.9{\sim}10.1$년)이었다. 진단명은 심실중격결손을 동반한 폐동맥 폐쇄증이 6예, 총동맥간이 2예, 완전 대혈관 전위가 1예였다. 술 전 평균 우심실유출로 압력차는 $88.3{\pm}22.2mmHg\;(58{\sim}125mmHg$)였다. 1예에서는 단엽 우심실유출로 첩포(monocusp ventricular outflow patch, MVOP)를 이용하였고 나머지 8예에서는 조직판막(bioprosthetic valve)을 삽입하였다. 모든 예에서 대동맥차단은 하지 않았으며 평균 체외순환시간은 154 ($133{\sim}181$분)이었다. 수술 후 평균 추적기간은 20개월($1{\sim}51$개월)이었으며 3-D CT로 우심실유출로의 상태를 관찰하였다. 결과: 수술사망과 만기사망은 없었다. 술 후 퇴원 시 우심실유출로 평균 압력차이는 $20.4mmHg\;(0{\sim}29.6mmHg$)였다. peel 수술 후 재수술은 없었으며 최근 초음파 검사에서 우심실 압력차이 (n=7, 최소 1년 이상 추적)는 26 mmHg ($13{\sim}36mmHg$)으로 약간의 상승은 있었으나 MVOP를 사용한 1예를 제외한 전 예에서 폐동맥판 폐쇄부전은 없었다. 3-D CT검사상 우심실유출로의 수축, 혈전형성, 가성동맥류의 증거는 발견하지 못하였고 우심실유출로의 통로가 잘 유지되고 있었다. 결론: peel 수술은 라스텔리 수술 후 도관협착을 해결할 수 있는 안전하고 효과적인 수술법으로 생각한다.

• Bulletin of the Korean Chemical Society
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• 제31권1호
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• pp.246-249
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• 2010