• 대한안전경영과학회지
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• 제17권3호
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• pp.343-353
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• 2015

The purpose of this study includes: Firstly, to examine the effects of corporate entrepreneurship on market orientation, radical innovation, and organizational performance. Secondly, to examine the mediating effect of the market orientation, radical innovation on the relationship between corporate entrepreneurship and organizational performance. In order to verify the relationships and mediating effect, data were collected from convenient sample of 269 employees at small and medium enterprises in Busan, Ulsan, Gyeongju city to test theoretical model and its hypotheses. All data collected from the survey were analyzed using with SPSS 18.0 and AMOS 18.0. This study reports findings as followed: first, the relationship between the corporate entrepreneurship and the market orientation is positively related. Second, there was also a positive correlation between the corporate entrepreneurship and the radical innovation. Third, there was also a positive correlation between the market orientation and the radical innovation. Fourth, the relationship between the market orientation and the organizational performance is positively related. Fifth, there was also a positive correlation between the corporate entrepreneurship and the organizational performance. Sixth, there was also a positive correlation between the radical innovation and the organizational performance. Finally, the market orientation played as a partial mediator on the relationship between corporate entrepreneurship and radical innovation. The market orientation and radical innovation played as a partial mediator on the relationship between corporate entrepreneurship and organizational performance. Also, the radical innovation played as a partial mediator on the relationship between market orientation and organizational performance. Based on these findings, the limitations of the study and some directions for future studies were presented.

• 대한화학회지
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• 제24권3호
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• pp.250-258
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• 1980

여러종류의 자유라디칼들이 이소니트릴에 첨가되어 중간체인 imidoyl 자유라디칼 RN=CR'을 형성한다. 이것은 또한 imine으로부터 imidoyl hydrogen 을 떼어 내는 다음과 같은 반응에 의해서도 생성될 수 있다. RN=C(H)R' ＋ R"${\cdot}{\rightarrow}$ RN=CR' ＋ R"-H 중간체인 imidoyl 자유라디칼은 ${\beta}$-cleavage 및 aton transfer 반응을 통해서 안정된 분자를 형성한다. ${\beta}$-cleavage는 imidoyl 자유라디칼의 구조에 따라서 두개의 다른 방향으로의 반응이 가능하다. Cyanide transfer와 소위 말하는 정상적인 ${\beta}$-cleavage가 그러한 반응들이다. t-Butoxy 자유라디칼이 t-butylisonitrile 7에 첨가되면 중간체인 t-Bu-N=C-O-Bu-t가 생성되는데, 이것은 ${\beta}$-cleavage반응을 통해서 t-butylisocyanate와 t-butyl 자유라디칼을 형성한다. Phenyl 자유라디칼은 7에 첨가되어 중간체인 t-Bu-N=$C-C_6H_5$를 형성하는데 이것은 cyanide transfer 반응을 통해서 benzonitrile과 t-butyl 자유라디칼로 분해된다. 여기서 생성되는 t-butyl 자유라디칼은 다시 7에 첨가하여 intermediate인 자유라디칼 t-Bu-N=C-Bu-t을 형성하고, 이것은 다시 pivalonlonitrile과 t-butyl 자유라디칼로 분해되는데 이러한 반응이 반복되므로 radical chain isomerization을 일으킨다. Silyl 자유라디칼은 7에 첨가되어 t-Bu-N=$C-Si(CH_3)_3$를 형성하고, 이것은 cyanide transfer 반응을 거쳐서 다시 $(CH_3)_3$SiCN과 t-butyl 자유라디칼로 분해된다.

• Bulletin of the Korean Chemical Society
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• 제31권3호
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• pp.595-598
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• 2010

Ab initio and DFT molecular orbital calculations predict that acetyl radical reacts with acetylene through interactions primarily involving the SOMO of the radical and the in-plane ${\pi}$-bond of acetylene. An energy barrier (${\Delta}E_1$) of 39.6 kJ $mol^{-1}$ is predicted for the preferred anti arrangement of reactants at the CCSD(T)/cc-pVDZ//BHandHLYP/cc-pVDZ level of theory. NBO analysis reveals additional interactions between the radical SOMO and the nearby C-H ${\sigma}$-bond in acetylene worth about 10% of the total transition state interaction energy. This type of orbital interaction has not previously been observed in radical addition reactions involving C-C ${\pi}$-bonds.

• 한국해양바이오학회지
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• 제2권3호
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• pp.187-191
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• 2007

The radical scavenging activity of methanol extracts of seaweeds and their active compounds, alginic acid, fucoidan and phloroglucinol, were investigated under in vitro. Among methanol extracts of seaweeds (sea mustard, sea tangle, seaweed papulosa, fusiforme, sea lettuce, purple laver and chlorella), seaweed papulosa and sea tangle showed strong scavenging activities of 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical and hydroxyl radical (${\cdot}OH$). In addition, under in vitro, the scavenging activities on DPPH radical of alginic acid and fucoidan, which are active compounds of brown algae, and phloroglucinol, the active compound from Ecklonia species, were evaluated and compared. Fucoidan and phloroglucinol showed strong DPPH scavenging effect, in particular, phloroglucinol had strongest activity among the active compounds. On the other hand, alginic acid did not exert DPPH scavenging activity. From the present study, we could confirm the antioxidative activity of seaweeds and its active compounds.

• Bulletin of the Korean Chemical Society
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• 제23권1호
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• pp.103-106
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• 2002

A new reaction mechanism is proposed for the reaction of thianthrene cation radical perchlorate $(Th^{+{\cdot}}CIO_4^-}$ and tert-butyl peroxide in acetonitrile at room temperature on the basis of experimental and theoretical results. Rapid C-O bond rupture instead of O-O bond cleavage was observed by a good peroxy radical trapping agent, thianthrene cation radical. Products were N-tert-butyl acetamide, thianthrene 5-oxide (ThO), thianthrene 5,5-dioxide $(SSO_2)$, and thianthrene (Th). Thianthrene 5,10-dioxide (SOSO) was not obtained. A comparative computational study of the cation radical of tert-butyl peroxide is made by using B3LYP and CBS-4. The computational results are helpful to explain the reaction mechanism.

• 한국응용과학기술학회지
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• 제33권3호
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• pp.492-497
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• 2016

The intermediate product resulting from the radical degradation experiment of PCE and the atomic charge gained through Gaussian03W were compared against each other. The result was that the ratio of PCE radical degradation was almost 98% or higher after the 9 hr point in reaction time. The reaction speed constant was $0.16hr^{-1}$ and it followed the first reaction. We could see that at each location of the PCE molecule, dechlorination happened at a point where the negative atomic charge was the greatest. Moreover, the intermediate product of PCE radical degradation that was confirmed in the experiment and literature coincided exactly with the intermediate product in the atomic charge calculation. Therefore, when the atomic charge is calculated, the radical degradation pathway of the organic chlorine compound could be forecast.

• Natural Product Sciences
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• 제19권2호
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• pp.186-191
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• 2013

Screenings of potential antioxidant activities of Crataegus pinnatifida BUNGE Major. fruits extracted 80% methanol were performed using four antioxidant assays. Significant differences were observed both in total phenolic contents (TPC) and total flavonoid contents (TFC), DPPH radical scavenging activity, nitric oxide scavenging activity, ABTS radical scavenging assay, and reducing power assay. The total polyphenol content and total flavonoid content in the extract were measured to be $224.4{\pm}0.52$ mg GAE/100 g and $12{\pm}0.25$ mg QE/100 g, respectively. When the tested concentration was $500{\mu}g/mL$, DPPH and ABTS radical-scavenging activities of methanolic extracts were 84.15% and 88.8%, respectively. The reducing power and nitric oxide scavenging activity were increased at the manner of dose-dependently. These results suggest that methanolic extracts of Crataegus pinnatifida Bge. fruits possess excellent radical scavenging activities and may serve as a potential source of natural antioxidant.

• 대한수학회보
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• 제34권2호
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• pp.205-209
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• 1997

Hong et al. [2] and Jun et al. [4] introduced the notion of k-nil radical in a BCI-algebra, and investigated its some properties. In this paper, we discuss the further properties on the k-nil radical. Let A be a subset of a BCI-algebra X. We show that the k-nil radical of A is the union of branches. We prove that if A is an ideal then the k-nil radical [A;k] is a p-ideal of X, and that if A is a subalgebra, then the k-nil radical [A;k] is a closed p-ideal, and hence a strong ideal of X.

• 대한수학회보
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• 제32권2호
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• pp.367-372
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• 1995

In 1955 Singer and Wermer [12] proved that every bounded derivation on a commutative Banach algebra maps into its radical. They conjectured that the continuity of the derivation in their theorm can be removed. In 1988 Thomas [13] proved their conjecture ; Every derivation on a commutative Banach algebra maps into its radical. For noncommutative versions, in 1984 B. Yood [15] proved that the continuous derivations on Banach algebras satisfing [D(a),b] $\in$ Rad(A) for all a, b $\in$ A have the radical range, where [a,b] will be denote the commutator ab-ba. In 1990 M.Bresar and J.Vukman [1] have generlized Yood's result, that is, the continuous linear Jordan derivation on Banach algebra that satisfies [D(a),a] $\in$ Rad(A) for all a $\in$ A has the radical range. In next year Mathieu and Murphy [5] proved that every bounded centralizing derivation on Banach algebras has its image in the radical. Mathieu and Runde [6] removed the boundedness of that.

• 대한기계학회:학술대회논문집
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• 대한기계학회 2000년도 추계학술대회논문집B
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• pp.715-719
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• 2000

It is reported that we are facing the serious environment pollution difficulties such as acid rain, green house effects, etc. The gaseous matter CO, NOx, SOx, VOCs which are regarded as main factors for these current pollutions are mainly emitted from power plants and vehicles. Therefore several leading countries are regulating the related laws strictly, especially exhaust emissions from a Diesel engine without an after treatment device. The Objective of this study is to find out NOx removal characteristics focused on emissions of a Diesel engine using radical at each engine speed and load. It is generated from outer air and put into a mixing chamber in the end of exhaust line. In addition, the optimum temperature condition to activate reaction by radical is experimentally carried out. Concentration of exhaust emissions is analyzed from the gas anlayzer(KaneMay) and FTIR to estimate by-products.