Tris(2-cyclohexylaminoethyl)amine-Zn(II) 착물의 안정성

신용운,백현숙,양재경,김진은,서무룡,Yong Woon Shin,Hyun Sook Baek,Jae-Kyung Yang,Jineun Kim,Moo Lyong Seo 대한화학회 2003 대한화학회지 Vol.47 No.2

Tris(2-cyclohexylaminoethyl)amine (L) was synthesized by the Schiff base condensation reaction of tris(2-aminoethyl)amine with cyclohexanone, followed by reduction. The thermodynamic characteristics, mole ratio and formation constant of [Zn(II)-L] complex were measured by the cyclic voltammetry and isothermal titration. In the case of Zn(II), well-defined cathodic and anodic peak were obtained at -1.02V and -0.48V vs Ag/AgCl , respectively. For the [Zn(II)-L] complex, both peaks were obtained at -1.19V and -0.45V vs Ag/AgCl, respectively. In addition, the peak height gradually increases as the scan rate increases, suggesting that the currents obtained were diffusion - controlled. The mole ratio and stability constant of the complex measured cyclic voltammerty were 1:1 and logK$_f$= 5.8, respectively. And the mole ratio and stability constant of the complexe calculated by isothermal titration method was 1:1 and logK =5.4, respectively. ${\Delta}$H, ${\Delta}$G and T${\Delta}$S for the complex formation were -53.0 kJ/mol, -31.1 kJ/mol, and -21.9 J/K at 25 ${\circ}$C, respectively. Cyclohexanone,과 tris(2-aminoethyl)amine을 이용하여 Schiff 연기 축합반응으로 tren의 유도체인 tris(2-cyclohexylaminoethyl)amine (L)을 합성하였다. 또한 합성한 tren의 유도체인 tris(2-cyclohexylaminoethyl)amine (L)과 Zn(II) 착물의 열역학적 특성과 안정도 상수, Zn(II)와의 착물 조성비 등을 순환전압전류법과 열량계법으로 측정하였다. Zn(II)과 [Zn(II)-L] 순환전압전류 곡선을 0${sim}$-1.5 V vs. Ag/AgCl의 가전압 범위에서 측정하였다. 금속인 경우, -1.02V와 -0.48V vs. Ag/AgCl에서 각각 환원피이크와 산화피이크가 나타났으며, 금속착물인 경우에는 -1.19V와 -0.45V vs. Ag/AgCl에서 각각 환원피이크와 산화피이크가 나타났다. 또한 피이크 전류(IP)는 주사속도의 평방근 $(v^{1/2})$에 비례하였으며 이것은 전류의 유형이 확산 지배적인 전류임을 나타낸다. 그리고 [Zn-L] 착물에 대해서 전압전류법적으로 구한 안정도상수는 logK$_f$ = 5.8, 결합비는 1:1을 나타내었다. 또한 열량계법적으로 [Zn-L] 착물의 열역학적 파라메타를 조사한 결과, 리간드 L과 Zn(II)는 1:1의 4 배위수를 가지는 착물을 이룬다는 것을 알 수 있었고, 이때 25 ${\circ}$C에서 logK=5.4, ${\Delta}H$= -53.0 kJ/mol, ${\Delta}$G의 값은 -31.1 kJ/mol이었으며 T${\Delta}$S는 -21.9 J/K${\cdot}$mole이었다.

Biological Safety Evaluation of Polyketones as Biomaterials

Mi Hee Lee(이미희),Dae-Hyung Lee(이대형),Hyun-Sook Baek(백현숙),Byeong-Ju Kwon(권병주),Min-Ah Koo(구민아),Min Sung Kim(김민성),Gyeung Mi Seon(선경미),Jong-Chul Park(박종철) 한국고분자학회 2016 폴리머 Vol.40 No.2

생체재료는 의료기기로서 임상에 적용되기 위해서는 생물학적 안전성 평가에 의한 생체적합성 확보가 필수적이다. 이번 연구에서는 폴리케톤 고분자의 생체재료로서 사용 가능성을 평가하기 위해 생물학적 안전성 평가를 실시하였다. 폴리케톤 고분자의 용출물로 고분자의 생체적합성을 판단하는 생물학적 안전성 초기실험인 세포독성, 유전독성, 피부자극성, 감작성, 전신독성 시험을 실행하였다. 모든 시험에서 폴리케톤 고분자는 독성을 유발하지 않음을 확인할 수 있었으며, 이러한 결과는 폴리케톤 고분자가 생체재료로서 생물학적 안전성이 있으며 비분해성 고분자를 대체할 수 있을 것으로 판단된다. Biomaterials for clinical applications such as medical and implant devices require evaluation to determine their biocompatibility. This study aimed to evaluate the initial biological safety of polyketone (PK) polymers, which have potential use as biomaterials. It presents results from cytotoxicity and genotoxicity assays and tests determining the levels of skin irritation, sensitization, and acute systemic toxicity caused by PK. The PK polymers showed no cytotoxicity, genotoxicity, allergenicity, irritancy, and systemic toxicity. These results indicate that the PK polymers are potentially biological safe and could be used to replace non-degradable polymeric biomaterials.

호텔경영에 있어서 효과적인 아웃소싱 ( outsourcing ) 운영방안

김홍범(Hong Bumm Kim),구자혁(Cha Hyeok Ku),백현숙(Hyun Sook Baek) 한국호텔외식관광경영학회 2002 호텔경영학연구 Vol.11 No.1

This study attempted to research an actual situation and status of outsourcing in the super deluxe hotels, Seoul region and pursued for future operation and reform plans. The data of this study was taken from the specialists of personnel and general affairs section chiefs generally grasping the present condition of labor demand and supply for super deluxe hotels in Seoul region. The results of the questionnaires analyzed by frequency analysis and Kendall`s W coefficient of concordance are as followings; First, as to the performance purpose of outsourcing, the descending highest rates are `reduction of operation cost`, `profit-increase through restructuring`, `management /control difficult affairs`. Second, as to the selection element of vendors, `price condition`, `A/S including service level` and `confidence in management capability for relevant area` were significant factors. Third, the disadvantages of outsourcing were `degrading of service quality, deterioration of regular personnel`s labor will` and `difficulty of uniform strategic management`. Fourth, the important success factors of outsourcing were enumerated as `maintenance mutual reliable relationship`, `selection of right businesses`, `harmony of a company goal and a target`. Fifth, it was found the satisfaction of outsourcing was extremely high in cost reduction, which was consistent with the purpose of performance. The judgement of outsourcing is only made when three points are consistent; if it has compulsory power, if a using company can get higher quality than expected and it the vendor has specialization. To support this, it is needed related laws should be revised, and deregulated, and operations control should be adjusted to the actual condition of super deluxe hotels.

일부 지역 청소년의 인터넷 및 휴대폰 중독 실태

강은실(Eun-Sil Kang),손조욱(Jo-Wook Son),박소연(So-Yeon Park),이미선(Mi-Sun Lee),백현숙(Hyun-Sook Baek) 고신대학교 전인간호과학연구소 2008 전인간호과학학술지 Vol.3 No.-

Purpose: This study investigated the degree and frequency of Internet and cellular phone addiction of Korean adolescents to provide basic data for prevention and intervention. Methods; The subjects of the research were 336 students selected out of 1 middle school and 2 high schools of P city in Korea. The data was collected by the use of a structured questionnaire. A survey tool was used that was developed in the Center for On-line Addiction (1996) to investigate Internet addiction by Young (1996) and Jang s (2002) Cellular Phone Addiction Test. The data was analyzed with the SPSS 12.0/PC program. Results: The percentage of the adolescents who had Internet addiction tendency was 30.1% and cellular phone addiction tendency was 26.2%. The percentage of the reason as to why they used the Internet was for fun in 55.1% and the Internet using experience was over 5 years in 72.9%. The percentage of those who used the Internet daily was 33.8%. The percentage of those who used cellular phones for over 3 years was 31.3% and the reason why they bought cellular phones was because their friends had cellular phones and this was the case in 32.1%. The percentage of those who had sent text messages in class were 63.7%. The degree of cellular phone addiction was significantly high in female, middle school students, related Conclusions: Related variables in Internet and cellular phone addiction should be done involving a correlative study and all kinds of different schools need to be investigated (such as vocational high schools). Therefore the results of this study can be used as a basic data to develop a prevention program for Internet and cellular phone addiction.

우측 이하선에 발생한 혼합종의 외과적 치험례

이용오,문선혜,서혜경,백현숙 啓明大學校 醫科大學 1990 계명의대학술지 Vol.9 No.1

The patient presenting with a mass lesion of the parotid is frequently found to have mixed tumors of salivary tissue origin. The lesion is more common in females and inpatients of the median age of 50 years old. Recurrence of the mixed tumor is 0 to 50%. So avoidance of fragmentation or rupture of the tumor and removal of wide marginal tissue along with the tumor during surgery should be emphasized. From the surgical point of view. because of operative risk of facial nerve damage, the most important anatomical structure in relation to the parotid gland is seventh cranial nerve. Of the case reported here, benign mixed tumor occurred in the right parotid region of a 40 year old female patient, treated with surgical excision with preservation of 7th cranial nerve. Eight months follow-up evaluation showed good prognosis, and no evidance of complication and/on recurrence.

N-(Arylsulfonyl)benzimidoyl Chloride 유도체의 가수분해 메카니즘에 대한 반응속도론적 고찰

백현숙,이광순,허태성 가톨릭대학교 자연과학연구소 1992 자연과학논문집 Vol.13 No.-

N-(arylsulfonyl)benzimidoyl chloride 유도체들이 가수분해 반응을 반응속도론적으로 다루었다. EHMO계산법을 적용하여 N-(arylsulfonyl)benzimidoyl chloride의 배열, 분자의 반응 중심인 α탄소 원자의 양하전, E_(HOMO-LUMO) 및 S_(N) 1과 S_(N) 2반응 중간체의 상대성 안정성을 결정하였다. 이 결과로 부터 N-(arylsulfonyl)benzimidoyl chloride 유도체의 가수분해는 pH9이하에서 S_(N) 2 반응 메카니즘에 의해 진행됨을 알 수 있었다. The hydrolysis of N-(arylsulfonyl)benzimidoyl chloride derivatives were studied kinetically. As the results of EHMO calculation, the conformation of N-(arylsulfonyl) benzimidoyl chloride molecule, positive charge of Cα atom, which is the reaction center of molecule, E_(HOMO-LUMO) and the stability of intermediate of S_(N) 1 or S_(N) 2 reaction were determined. On the basis of these findings, one can conclude that the hydrolysis of N-(arylsulfonyl)benzimidoyl chloride derivatives proceeds by S_(N) 2 mechanism, below pH 9.00.