• Title/Summary/Keyword: spin transfer

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Technology Commercialization from Research Institutes to ICT-based Spin-offs (ICT기반 연구소기업의 기술사업화)

  • Park, Jae-Sue
    • Journal of the Korea Institute of Information and Communication Engineering
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    • v.23 no.6
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    • pp.690-696
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    • 2019
  • New companies expecting market penetration by adopting technology commercialization process could face high uncertainty and constraints. In particular, ICT-based firms that enter competitive markets must deal with more complex situations. Although in-depth research has been done to solve the problem, there is still a lack of understanding of how startups' technology commercialization process is successful. To discuss the issue, this paper presents the technology commercialization model and determinants.(policy, finance, work team, organizational culture, overcoming the difficulties etc.) the suitability of the framework. From this analysis it emerged that the sustainability of organizational capabilities is as important as the adherence to the technology commercialization process for companies. As the organizational capacity has decreased, the driving force for technology commercialization has weakened. Therefore, the technology commercialization process does not guarantee the success of the market entry but is understood as a means of market access. If the organizational capacity is not strengthened, there is no successful technology commercialization process.

Factors Influencing Technology Commercialization of Universities in Korea : Systematic Literature Review on Domestic Research (우리나라 대학의 기술사업화 영향요인 연구 : 국내 논문에 대한 체계적 문헌 고찰)

  • Lee, Cheol-Ju;Choi, Jong-in
    • Journal of Korea Technology Innovation Society
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    • v.22 no.1
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    • pp.50-84
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    • 2019
  • As the technology commercialization of American universities has been greatly activated since the implementation of the Bayh Dole Act, that of Korean universities has been steadily increasing since the enactment of the Technology Transfer Promotion Act of 2000, due to numerous related laws, government support programs, and accumulated experience of technology transfer. However, the level of technology commercialization of domestic universities is still insufficient in comparison to that of advanced countries such as the United States. So, in this study, we tried to identify factors promoting technology transfer and start-ups in Korean universities by examining domestic prior researches carried out since 2000 using SLR (Systematic Literature Review) methodology. As a result of our analysis, researches in the field of technology transfer were the most studied while papers on start-up are actively increasing recently. As for factors influencing commercialization of technology, internal and external factors were identified. The former were categorized as human resource, technology and knowledge resource, financial resource, managing resource and strategy, university type, and education and culture, while the latter were grouped into consumer, region, and infrastructure. And then detailed factors were integrated in each field by systematic mapping. Our study has its meaning in that it systematically accumulated the results of researches on technological commercialization of Korean universities and identified areas that are lacking or need additional research. And the integrated promoting factors for technology transfer or start-up can also be used as a checklist for universities or public institutes.

Analysis of Influencing Factors of Cyber Weapon System Core Technology Realization Period (사이버 무기체계 핵심기술 실현시기의 영향 요인 분석)

  • Lee, Ho-gyun;Lim, Jong-in;Lee, Kyung-ho
    • Journal of the Korea Institute of Information Security & Cryptology
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    • v.27 no.2
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    • pp.281-292
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    • 2017
  • It is demanded to promote research and development of cyber weapons system and core technology in response to the ongoing cyber attack of North Korea. In this paper, core technologies of the future cyber weapon system are developed and the factors affecting the realization timing of core technologies were analyzed. 9 core technology groups and 36 core technologies are derived. Afterwards, these core technology groups are compared to the operation phase of the joint cyber warfare guideline and the cyber kill chain of Lockheed Martin. As a result of the comparison, it is confirmed that the core technology groups cover all phases of the aforementioned tactics. The results of regression analyses performed on the degree of influence by each factor regarding the moment of core technology realization show that the moment of core technology realization approaches more quickly as factors such as technology level of the most advanced country, technology level of South Korea, technology transfer possibility from the military sector to the non-military sector(spin-off factor), and technology transfer possibility from the non-military sector to the military sector(spin-on factor) increase. On the contrary, the moment of core technology realization is delayed as the degree at which the advanced countries keep their core technologies from transferring decrease. The results also confirm that the moment of core technology realization is not significantly correlated to the economic ripple effect factor. This study is meaningful in that it extract core technologies of cyber weapon system in accordance with revision of force development directive and join cyber warfare guideline, which incorporated cyber weapon system into formal weapon system. Furthermore, the study is significant because it indicates the influential factor of the moment of core technology realization.

Magnetism and Magnetocrystalline Anisotropy of CoFe Thin Films: A First-principles Study (CoFe 박막의 자성과 자기결정이방성에 대한 제일원리계산)

  • Kim, Eun Gu;Jekal, So Young;Kwon, Oryong;Hong, Soon Cheol
    • Journal of the Korean Magnetics Society
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    • v.24 no.2
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    • pp.35-40
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    • 2014
  • We investigate magnetism and magnetocrystalline anisotropy of CoFe thin films, using VASP code in GGA. In this study Co-terminated and Fe-terminated 5-layer CoFe thin films are employed. The Co-terminated CoFe thin film shows two total energy minima at 2-dimensional lattice constants of $2.45{\AA}$ and $2.76{\AA}$. The film of $2.45{\AA}$ has fcc-like structure and the film of $2.76{\AA}$ has bcc-like structure similarly to a bulk CoFe alloy. And the fcc-like film is more stable by the energy difference of about 160 meV compared to the bcc-like film. The Fe-terminated CoFe film shows very complicated behaviour of total energy which is suspected to be closely related to its complex magnetic structure. The Co-terminated CoFe film of $2.76{\AA}$ shows perpendicular magnetocrystalline anisotropy (MCA), while the film of 2.45 does parallel MCA. The Fe-terminated CoFe film also exhibits similar MCA behaviour.

Photophysical Efficiency Factors of Singlet Oxygen Generation from Core-modified Trithiasapphyrin Derivatives

  • Ha, Jeong-Hyon;Kim, Min-Sun;Park, Yong-Il;Ryu, Shin-Hyung;Park, Mi-Gnon;Shin, Koo;Kim, Yong-Rok
    • Bulletin of the Korean Chemical Society
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    • v.23 no.2
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    • pp.281-285
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    • 2002
  • The photophysical properties and the singlet oxygen generation efficiencies of meso-tetraphenyl-trithiasapphyrin $(S_3TPS)$ and meso-tetmkis(p-methoxy phenyl)-trithiasapphy rin ((p-MeO)-$S_3TPS$) have been investigated, utilizing steady-state and time-resolved spectroscopic methods to elucidate the possibility of their use as photosensitizers for photodynamic therapy (PDT). The observed photophysical properties were compared with those of other porphyrin-like photosensitizers in geometrical and electronic structural aspects, such as extended ${\pi}$ conjugation, structural distortion, and internal heavy atoms. The steady-state electronic absorption and fluorescence spectra were both red-shifted due to the extended ${\pi}$-conjugation. The fluorescence quantum yields were measured as very small. Even though intersystem crossing rates were expected to increase due to the increment of spin orbital coupling, the triplet quantum yields were measured as less than 0.15. Such characteristics can be ascribed to the more enhanced internal conversion rates compared with the intersystem crossing rates. Furthermore, the triplet state lifetimes were shortened to -1.0 ${\mu}s$ as expected. Therefore, the singlet oxygen quantum yields were estimated to be near zero due to the fast triplet state decay rates and the inefficient energy transfer to the oxygen molecule as well as the low triplet quantum yields. The low efficiencies of energy transfer to the oxygen molecule can be attributed to the lower oxidation potential and/or the energetically low lying triplet state. Such photophysical factors should be carefully evaluated as potential photosensitizers that have extended ${\pi}$-conjugation and heavy core atoms synthesized for red-shifted absorption and high triplet state quantum yields.

Synthesis and Characterization of Tetrathiafulvalene (TTF) and 7,7,8,8-Tetracyanoquinodimethane (TCNQ) Compounds with PdX2(X=CI, NO3and Hexafluoroacetylacetonate)

  • Kim, Young-Inn;Jeong, Chan-Kyou;Lee, Yong-Min;Choi, Sung-Nak
    • Bulletin of the Korean Chemical Society
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    • v.23 no.12
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    • pp.1754-1758
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    • 2002
  • Tetrathiafulvalene(TTF) reacts with $PdCl_2,Pd(NO_3)_2$ and $Pd(hfacac)_2$(hexafluoroacetylacetonate) in ethanol to give $(TTF)_{1.5}PdCl_2$ (1a), $(TTF)_3Pd(NO_3)_2$ (1b) and $(TTF)_4Pd(hfacas)_2$ nd (1c), respectively. $PdCl(TCNQ)_{2.5}{\cdot}CH_3OH(2a)$was obtained from the reaction of $PdCl_2$ with LiTCNQ in methanol via the partial replacement of $Cl^-$ in $PdCl_2$ by $TCNQ^-$anion, whereas the total substitution of the labile $NO_3^-$ in $Pd(NO_3)_2$ yielded pd(TCNQ)·$CH_3OH$ (2b). $Pd(hfacac)_2(TCNQ)_2\cdot3CH_3OH$ (2c) was obtained from $Pd(hfacac)_2$ and LiTCNQ in methanol. The prepared compounds were characterized by spectroscopic (IR, UV, XPS) methods and magnetic (EPR, magnetic susceptibility) studies. The powdered electrical conductivities (${\sigma}_{rt}$) of the prepared compounds at room temperature were about~$10^{-7}S{\cdot}cm^{-1}$. The effective magnetic moments were lass than the spin-only value of one unpaired electron and no EPR signals from Pd metal ions were observed in any of the compounds, indicating that the Pd ions were diamagnetic and the magnetic moments arose from$(TTF)_n$ or $(TCNQ)_n$ moieties. The experimental evidences revealed that the charge transfer had occurred form $(TTF)_n$ moiety to the central Pd metal ion in 1a, 1b and 1c. Thus the TTF donors were ions in 2a and 2b were diamagnetic Pd(II) oxidation state. In contrast, the Pd metal ion was oxidized to Pd(IV) state in 2c as a result of an addition of $TCNQ^-$anion to $Pd(hfacac)_2$ in methanol. The oxidation states of the Pd metal ions were confirmed using the x-ray photoelectron spectroscopy.

Synthesis, Characterization, and Crystal Structures of Iron(Ⅱ) and Manganese(II) Complexes with 4,7-bis(2-pyridylmethyl)-1-thia-4,7-diazacyclononane

  • Delong Zhang;Daryle H. Busch;Nathaniel W. Alcock
    • Bulletin of the Korean Chemical Society
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    • v.19 no.9
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    • pp.897-906
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    • 1998
  • A new synthesis has been developed for 1-thia-4,7-diazacyclononane and the complexation behavior of a particular derivative has been explored. The pentadentate ligand 4,7-bis(2-pyridylmethyl)-l-thia-4,7-diazacyclononane ([9]$N_2SPY_2$) and its iron(Ⅱ) and manganese(Ⅱ) complexes were prepared and characterized. Magnetic moments of 5.17 and 5.90 μB respectively, indicate that the iron(Ⅱ) and manganese(Ⅱ) complexes are high spin. Charge transfer transitions (d-π*) occur for [Fe(Ⅱ)([9]$N_2SPY_2)(X)]^{n+}$at 27027, 25000, and 24390 cm-1 for X=$H_2O$, Cl-, and OH-, respectively. In acetonitrile solution, the cyclic voltammogram of the manganese(Ⅱ) complex exhibits a redox couple at 0.92 V vs. NHE while the redox potentials for [Fe(Il)([9]$N_2SPY_2)(X)]^{n+}$ are 0.70, 0.66, and 0.37 V vs. NHE for X=$H_2O$, Cl-, and OH-, respectively. The d-π* charge transfer energy and Fe(Ⅱ)/Fe(Ⅲ) redox potential for [Fe(Ⅱ)([9]$N_2SPY_2)(X)]^{n+}$ increase in the same order: $H_2O>Cl^- >OH^-$. The crystal structures of the iron(Ⅱ) and manganese(Ⅱ) complexes reveal that the metal ions are sixcoordinate, binding to four nitrogen atoms and a sulfur atom from the pentadentate ligand, as well as a chloride anion, with the chloride and sulfur atoms in cis positions. The two metals have similar coordination geometries, which are closer to trigonal prismatic than octahedral. In both iron and manganese complexes, the M-N($sp_3$) trans to Cl- is 0.07 Å longer than the one cis to Cl- , and M-N($sp^2$) trans to S is 0.05 longer than the one cis to S atom.

Synthesis and Characterization of the Mixed-valence $[Fe^{II}Fe^{III}BPLNP(OAc)_2](BPh_4)_2$ Complex As a Model for the Reduced Form of the Purple Acid Phosphatase

  • Lee, Jae Seung;Jung, Dong J.;Lee, Ho Jin;Lee, Gang Bong;Heo, Nam Hoe;Jang, Ho G.
    • Bulletin of the Korean Chemical Society
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    • v.21 no.10
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    • pp.969-972
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    • 2000
  • [Fe II Fe III $BPLNP(OAc)_2](BPh_4)_2$ (1), a new model for the reduced form of the purple acid phosphatases, has been synthesized by using a dinucleating ligand, 2,6-bis[((2-pyridylmethyl)(6-methyl-2-pyridylmethyl)ami-no)methyl]-4-nitrophenol (HBPLNP) . Complex 1 has been studied by electronic spectral, NMR, EPR, SQUID, and electrochemical methods. Complex 1 exhibits two strong bands at 498 nm $(\varepsilon=$ 2.6 ${\times}10^3M-^1cm-^1)$ and 1363 nm $(\varepsilon=$ 5.7 ${\times}10^2M-^1cm-^1)$ in $CH_3CN.$ These are assigned to phenolate-to-FeIII and intervalence charge-transfer transitions, respectively. NMR spectrum of complex 1 exhibits sharp isotropically shifted resonances, which number is half of those expected for a valence-trapped species, indicating that electron transfer between FeⅡ and FeⅢ centers is faster than NMR time scale at room temperature. Complex 1 undergoes quasireversible one-electron redox processes. The $FeIII_2/FeIIFeIII$ and $FeIIFeIII/FeII_2$ redox couples are at 0.807 and 0.167 V ver-sus SCE, respectively. It has Kcomp = 5.9 ${\times}$10 1s(acetato) ligand combination sta-bilizes a mixed-valence FeIIFeIII complex in the air. Interestingly, complex 1 exhibits intense EPR signals at g = 8.56, 5.45, 4.30 corresponding to mononuclear high-spin FeⅢ species, which suggest a very weak magnetic coupling between the iron centers. Magnetic susceptibility study shows that there is a very weak antiferromag-netic coupling (J = $-0.78cm-^1$, H = $-2JS_1${\times}$S_2)$ between FeII and FeIII centers. Thus, we can suggest that complex 1 has a very weak antiferromagnetic coupling between the iron centers due to the electronic effect of the nitro group in the bridging phenolate ligand.

A New Functional Model of Catechol Dioxygenases: Properties and Reactivity of [Fe(BLPA)DBC]$BPh_4$

  • Lim, Ji H.;Lee, Ho J.;이강봉;Jang, Ho G.
    • Bulletin of the Korean Chemical Society
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    • v.18 no.11
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    • pp.1166-1172
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    • 1997
  • [FeⅢ(BLPA)DBC]BPh4, a new functional model for the catechol dioxygenases, has been synthesized, where BLPA is bis((6-methyl-2-pyridyl)methyl)(2-pyridylmethyl)amine and DBC is 3,5-di-tert-butylcatecholate dianion. The BLPA complex has a structural feature that iron center has a six-coordinate geometry with N4O2 donor set. It exhibits EPR signals at g=5.5 and 8.0 which are typical values for the high-spin FeⅢ (S=5/2) complex with axial symmetry. The BLPA complex reacts with O2 within a few hours to afford intradiol cleavage (75%) and extradiol cleavage (15%) products which is very unique result of all [Fe(L)DBC] complexes studied. The iron-catecholate interaction of BLPA complex is significantly stronger, resulting in the enhanced covalency of the metal-catecholate bonds and low energy catecholate to FeⅢ charge transfer bands at 583 and 962 nm in CH3CN. The enhanced covalency is also reflected by the isotropic shifts exhibited by the DBC protons, which indicate increased semiquinone character. The greater semiquinone character in the BLPA complex correlates well with its high reactivity towards O2. Kinetic studies of the reaction of the BLPA complex with 1 atm O2 in CH3OH and CH2Cl2 under pseudo-first order conditions show that the BLPA complex reacts with O2 much slower than the TPA complex, where TPA is tris(2-pyridylmethyl)amine. It is presumably due to the steric effect of the methyl substituent on the pyridine ring. Nevertheless, both the high specificity and the fast kinetics can be rationalized on the basis of its low energy catecholate to FeⅢ charge transfer bands and large isotropic NMR shifts for the BLPA protons. These results provide insight into the nature of the oxygenation mechanism of the catechol dioxygenases.

A New Model for the Reduced Form of Purple Acid Phosphatase: Structure and Properties of $[Fe_2BPLMP(OAc)_2](BPh_4)_2$

  • 임선화;이진호;이강봉;강성주;허남휘;Jang, Ho G.
    • Bulletin of the Korean Chemical Society
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    • v.19 no.6
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    • pp.654-660
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    • 1998
  • $[Fe^{II}Fe^{III}BPLMP(OAc)_2](BPh_4)_2$ (1), a new model for the reduced form of the purple acid phosphatases, has been synthesized by using a dinucleating ligand, 2,6-bis[((2-pyridylmethyl)(6-methyl-2-pyridylmethyl)amino) methyl]-4-methylphenol (HBPLMP). Complex I has been characterized by X-ray diffraction method as having (μ-phenoxo)bis(acetato)diiron core. Complex 1 was crystallized in the monoclinic space group C2/c with the following cell parameters: a=41.620(6) Å, b=14.020(3) Å, c=27.007(4) Å, β=90.60(2)°, and Z=8. The iron centers in the complex 1 are ordered as indicated by the difference in the Fe-O bond lengths which match well with typical $Fe^{III}-O\; and\; Fe^{II}-O$ bond lengths. Complex 1 has been studied by electronic spectral, NMR, EPR, SQUID, and electochemical methods. Complex 1 exhibits strong bands at 592 nm, 1380 nm in $CH_3CN$ (ε = 1.0 × 103 , 3.0 × 102). These are assigned to $phenolate-to-Fe^{III}$ and intervalence charge-transfer transitions, respectively. Its NMR spectrum exhibits sharp isotropically shifted resonances, which number half of those expected for a valence-trapped species, indicating that electron transfer between $Fe^{II}\;and\;Fe^{III}$ centers is faster than NMR time scale. This complex undergoes quasireversible one-electron redox processes. The $Fe^{III}_2/Fe^{II}Fe^{III}\;and\;Fe^{II}Fe^{III}/Fe^{II}_2$ redox couples are at 0.655 and -0.085 V vs SCE, respectively. It has $K_{comp}=3.3{\times}10^{12}$ representing that BPLMP/bis(acetate) ligand combination stabilizes a mixed-valence $Fe^{II}Fe^{III}$ complex in the air. Complex 1 exhibits a broad EPR signal centered near g=1.55 which is a characteristic feature of the antiferromagnetically coupled high-spin $Fe^{II}Fe^{III}$ system $(S_{total}=1/2)$. This is consistent with the magnetic susceptibility study showing the weak antiferromagnetic coupling $(J= - 4.6\;cm^{-1},\; H= - 2JS_1{\cdot}S2)$ between $Fe^{II}\; and \;Fe^{III}$center.