Probenecid, $C_{13}H_{19}NO_4S$의 結晶構造

김의성,신현소,Kim, Eui-Sung,Shin, Hyun-So Korean Chemical Society 1991 대한화학회지 Vol.35 No.6

Probenecid의 결정구조는 graphite-monochromated Mo-K${\alpha}$선을 사용하는 ENRAF-NONIUS CAD-4 자동 X-선 4축 회절기에서 수집된 2574개의 독립적 회절 반점들을 이용하여 결정되었다. 결정은 triclinic system에 속하고, 공간군은 P$\bar{1}$이며, 단위세포 상수는 a = 7.535(2)${\AA}$, b = 18.473 (5)${\AA}$, c = 5.317(9)${\AA}$, ${\alpha} = 92.00(5)^{\circ}$, ${\beta} = 99.02(5)^{\circ}$, ${\gamma} = 94.89(2)^{\circ}$, V = 727.4(2)${\AA}^3$이었다. 이 밖의 다른 parameters로서, Z = 2, $D_m$ = 1.310, $D_x = 1.302 gcm^{-3}$, ${\mu} = 1.88 cm^{-1}$, F(000) = 304, and T = 298 K이었다. 5${\sigma}(F_o)$ 이상인 1209개의 반점들에대한 최종 R및 $R_w$는 각각 0.0676과 0.0630이었다. 질소원자 N(13)의 공간배열에서, 결합각의 합은 350.9이며, 질소 주위의 세 원자가 이루는 평면에서 0.268(6)${\AA}$ 만큼 벗어나 있다. S(1)-C(4) 결합길이는 1.792(6)${\AA}$이며 C(4)-S(1)-N(13) 결합각은 $106.5(3)^{\circ}$이다. 분자의 전체적인 형태는 황에 대하여 접혀진 구조를 나타내고 있다. The crystal structure of Probenecid has been determined from 2574 independent reflections collected on an automatic ENRAF-NONIUS CAD-4 diffractometer using graphite-monochromated $Mo-K{\alpa}$ radiation. The crystal is triclinic, space group P$\bar{1}$ with unit cell dimensions a = 7.535(2)${\AA}$, b = 18.473 (5)${\AA}$, c = 5.317(9)${\AA}$, ${\alpha} = 92.00(5)^{\circ}$, ${\beta} = 99.02(5)^{\circ}$, ${\gamma} = 94.89(2)^{\circ}$, V = 727.4(2)${\AA}^3$, Z = 2, $D_m$ = 1.310, $D_x$ = $1.302 gcm^{-3}$, ${\mu}$ = $1.88 cm^{-1}$, F(000) = 304, and T = 298 K. Final R = 0.0676 and $R_w$ = O.0630 for 1209 reflections > 5${\sigma}(F_o)$. In the spacial arrangement about N(13), the sum of bond angles about nitrogen is 350.9° and the nitrogen lies only 0.268(6)${\AA}$ out of S(1)-C(14)-C(17) plane. The S(1)-C(4) distance is 1.792(6)${\AA}$ and the C(4)-S(1)-N(13) angle is $106.5(3)^{\circ}$. The overall conformation of the molecule is folded with respect to sulfur.

유효 듀티 손실이 없는 향상된 영전압 부분 직렬 공진형 DC/DC 컨버터

김의성(Kim Eui-Sung),이동윤(Lee Dong-Yun),현동석(Hyun Dong-Seok) 전력전자학회 2000 전력전자학술대회 논문집 Vol.2000 No.11

This paper presents an Improved ZVS partial series resonant DC/DC converter (PSRC) with low conduction losses, suitable for high power and high frequency applications. The proposed PSRC have advantages of zero-voltage-switching (ZVS) of main switches for entire load ranges and low conduction losses of main switches by decreasing current stresses. Also the reduction of the effective duty cycle is not occurred during the resonant period of the main circuit because the auxiliary circuit of the proposed converter is placed out of the main power path An Improved ZVS PSRC has a so much characteristics with respect to the overall system efficiency and to the reduction of current stress. The operation principles of the proposed converter are explained jndetail and the various simulated and experimental results show the validity of the proposed converter.

프리텐션 프리스트레스트 콘크리트 부재의 정착길이 평가

김의성 ( Eui Sung Kim ) 한국안전학회(구-한국산업안전학회) 2008 한국안전학회지 Vol.23 No.6

대기 환경조건을 고려한 콘크리트 교량 바닥판의 염소이온 침투 예측 모델

김의성 ( Eui Sung Kim ) 한국안전학회 2008 한국안전학회지 Vol.23 No.4

콘크리트 박스거더 교량 바닥판의 종방향 균열 위험성 평가

김의성 ( Eui Sung Kim ) 한국안전학회(구-한국산업안전학회) 2008 한국안전학회지 Vol.23 No.5

1,2- 그리고 1,3-디아민 유도체의 합성에 관한 연구(Ⅰ): 3-(N-벤질아미노)-4,4-디히드로-1,2,5-티아디아졸 1,1-디옥시드의 합성과 분자구조

이채호,김의성,정봉영,이영행,Lee, Chai-Ho,Kim, Eui-Sung,Chung, Bong-Young,Lee, Yeong-Haeng 대한화학회 1996 대한화학회지 Vol.40 No.7

3-Imino-1, 2, 5-thiadiazolidine 1, 1-dioxide와alkylamine 의 반응에 의하여 3-(N-alkylamino)-4, 5-dihydro-1, 2, 5-thiadiazole 1, 1-dioxide를 제조하였다. 이 헤테로고리 화합물의 주요 분광학적 성질과 X-선 결정학외절에 의한 분자구조를밝혔다. 3-(N-benzylamino)-4, 5-dihydro-4-(4'-methoxyphenyl)-1, 2, 5-thiadiazole 1, 1-dioxide의 단결정은 단사정계, 공간군은 $P2_1a$, $a=22.512(3)(1)\AA$, $b=9.831(2)\AA$, $c=7.194(4)\AA$, $\beta=96.65(2)$, 그리고 Z=4이다. 3-(N-Alkylamino)-4,5-dihydro-1,2,5-thiadiazole 1,1-dioxides have been prepared by the treatment of 3-imino-1,2,5-thiadiazolidine 1,1-dioxides with alkylamines. The selected spectral properties of these heterocycles are detailed, as well as an X-ray crystallographic structure of a representative member of these compounds. 3-(N-Benzylamino)-4,5-dihydro-4-(4'-methoxyphenyl)-1,2,5-thiadiazole 1,1-dioxide crystallyzes in space group $P2_1a$, monoclinic, with $a=22.512(3)(1)\AA$, $b=9.831(2)\AA$, $c=7.194(4)\AA$, $\beta=96.65(2)$, and Z=4.

The Effect of Surface Defects on the Cyclic Fatigue Fracture of HEROShaper Ni-Ti rotary files in a Dynamic Model: A Fractographic Analysis

이정규,김의성,강명희,금기연,Lee, Jung-Kyu,Kim, Eui-Sung,Kang, Myoung-Whai,Kum, Kee-Yeon The Korean Academy of Conservative Dentistry 2007 Restorative Dentistry & Endodontics Vol.32 No.2

본 연구의 목적은 니켈티타늄 전동파일의 피로파절에 있어서 표면 결함의 역할을 규명하고자 fatigue tester에서 반복적 인 fatigue force를 부여한 후 파절된 단면을 주사전자현미 경으로 관찰하여 파절 역학을 규명하는 것이다. 총 45개의 #30/.04 taper와 21 mm의 HEROShaper 니켈-티타늄 전동파일을 15개씩 3개의 군으로 분류하였다. 제 1군은 결함이 없는 새 HEROShaper파일, 제 2군은 제조과정에서 metal rollover나 machining marks와 같은 표면결함을 갖는 HEROShaper파일, 제 3군은 임상에서 4- 6개의 구치부 근관의 확대에 사용한 HEROShaper 파일을 사용하였다. 모든 파일들은 회전속도(300 rpm)와 pecking distance (3 mm)가 일정하게 맞춘 fatigue tester에서 파절될 때까지 시간을 측정한 후 통계분석을 통해 각 군간의 유의성을 분석하였고, 파절 단면의 farctographic analysis를 통해 파절역학을 규명하고자 하였다 실험결과 평균 파절시간에 있어서 group 1과 2, group 1과 3사이에는 통계학적으로 유의할 만한 차이가 있었으나 (p<0.05), group 2와 3사이에는 통계학적인 차이가 없었다. Fractographic analysis 결과 대부분의 파절면에서 microvoid와 dimple 소견을 갖는 ductile fracture양상이 관찰되었다. 또한 brittle fracture가 일어난 파절면에서는 파절선 전방에 수 많은 striation들이 관찰되었고 transgranular 및 intergranular cleavage 소견도 보였다. 표면결함이 있는 제 2, 3 군의 파절단면에서는 모든 시편에서 표면결함이 관찰되었다. 이와 같은 결과로 미루어 보아 표면결함이 반복 피로파절에서 미세균열의 기시점으로 중요한 역할을 하며 fractography분석법은 Ni-Ti 파일의 파절역학을 규명하는데 유용함을 알 수 있었다. This in vitro study examined the effect of surface defects on cutting blades on the extent of the cyclic fatigue fracture of HEROShaper Ni-Ti rotary files using fractographic analysis of the fractured surfaces. A total of 45 HEROShaper (MicroMega) Ni-Ti rotary flies with a #30/.04 taper were divided into three groups of 15 each. Group 1 contained new HEROShapers without any surface defects. Group 2 contained HEROShapers with manufacturing defects such as metal rollover and machining marks. Croup 3 contained HEROShapers that had been clinically used for the canal preparation of 4-6 molars A fatigue-testing device was designed to allow cyclic tension and compressive stress on the tip of the instrument whilst maintaining similar conditions to those experienced in a clinic. The level of fatigue fracture time was measured using a computer connected the system. Statistical analysis was performed using a Tukey's test. Scanning electron microscopy (SEM) was used for fractographic analysis of the fractured surfaces. The fatigue fracture time between groups 1 and 2, and between groups 1 and 3 was significantly different (p<0.05) but there was no significant difference between groups 2 and 3 (p>0.05). A low magnification SEM views show brittle fracture as the main initial failure mode At higher magnification, the brittle fracture region showed clusters of fatigue striations and a large number of secondary cracks. These fractures typically led to a central region of catastrophic ductile failure. Qualitatively, the ductile fracture region was characterized by the formation of microvoids and dimpling. The fractured surfaces of the HEROShapers in groups 2 and 3 were always associated with pre-existing surface defects. Typically, the fractured surface in the brittle fracture region showed evidence of cleavage (transgranular) facets across the grains, as well as intergranular facets along the grain boundaries. These results show that surface defects on cutting blades of Ni-Ti rotary files might be the preferred sites for the origin of fatigue fracture under experimental conditions. Furthermore this work demonstrates the utility of fractography in evaluating the failure of Ni-Ti rotary flies.

현초에서 분리한 생리활성물질의 항염증효과 (단보)

김보미,김의성,이영행,유병수,채규윤,Kim, Bo-Mi,Kim, Eui-Sung,Lee, Young-Hang,Yu, Byung-Soo,Chai, Kyu-Yun 대한한의학방제학회 2010 大韓韓醫學方劑學會誌 Vol.18 No.2

The Geranium nepalense has been used traditionally for treatment of various diseases. However, the molecular studies on the effect of Geranium nepalense have not been carried out. In the present study, Quercetin, quercitrin, and afzelin were isolated from the methanol extract of Geranium nepalense were tested for their anti-inflammatory effect. The anti-inflammatory effect of the compounds was studied in lipopolysaccharide(lps)-treated mouse macrophage cells, RAW 264.7. RAW 264.7 cells were pre-incubated with isolated compounds(0, 5, 10, 20, 40, $50\;{\mu}g/ml$) for 4h and treated with $1\;{\mu}g/ml$ lps for 18h, and then the anti-inflammatory effects of compounds were determined. The results are as follows: Quercetin at various concentration inhibited the viability of Raw 264.7 from 7% to 45%, quercitrin from 25% to 80%, and afzelin from 13% to 52%. Isolated compounds showed a significant decrease in iNOS (inducible nitric oxide synthase) and COX-2 (cyclooxygenase-2). These results suggest that these compounds can be used as stable anti-inflammatory materials.

고속철도 프리스트레스트 콘크리트 교량의 최신 시공기술

김광수,홍경옥,김의성,Kim Kwang Soo,Hong Kyung Ok,Kim Eui Sung 한국콘크리트학회 2004 콘크리트학회지 Vol.16 No.4

신경감압술을 이용한 외상성 안면신경마비의 치험례

김일규(Il Kyu Kim),이성호(Sung Ho Lee),오성섭(Sung Sup Oh),최진호(Jin Ho Choi),오남식(Nam Sik Oh),김의성(Eui Seong Kim) 대한구강악안면외과학회 2000 대한구강악안면외과학회지 Vol.26 No.3

Return of facial nerve function is important in patients with facial nerve paralysis by trauma. Sometimes, delay in diagnosis of facial nerve paralysis make recovery of facial nerve function difficult. Traumatic facial palsy mostly occur after temporal bone fracture in unilateral. Temporal bone fracture after head trauma are divided into the three group; longitudinal fracture, transverse fracture and mixed fracture. The most common symptoms are hearing impairment, bloody otorrhea, loss of consciousness and facial nerve paralysis. The early care of temporal bone fracture involves facial nerve paralysis. And there has been many discussion and study in the treatment of the immediate or delayed facial palsy ; examply, surgical approach, time and methods. We have managed a patient with unilateral facial nerve paralysis after longitudinal temporal bone fracture in mastoid process and conservative facial nerve decompression was performed. We have obtained good result and report this case with review of literatures.