• 제목/요약/키워드: M-N interaction

검색결과 438건 처리시간 0.024초

콘크리트 전주의 극한강도에 관한 해석적 연구 (An Analytical Study on the Ultimate Strength of Concrete Poles)

  • 신동근;윤기용;이승현;이규세;강영종
    • 한국방재학회 논문집
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    • 제7권5호
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    • pp.19-25
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    • 2007
  • 본 연구에서는 전주의 공칭강도를 계산하기 위해 이론적 방법에 의해 P-M상관도 프로그램을 개발하였다. 그리고 이를 바탕으로 기존 연구와 검증하고 전주의 공칭강도$(M_n)$를 산정하였다. 설계기준에 제시된 파괴강도$(M_r)$와 본 연구에서 산정한 전주의 공칭강도$(M_n)$를 비교 분석한 결과 현재 사용하고 있는 전주의 공칭강도가 설계기준$(M_r)$보다 작게 산정되었다. 따라서 공칭강도 증대를 위해 인장근/보강근의 지름 증가, 보강근의 개수 증가, 인장근의 위치변화, 전주의 두께 변화 등의 매개변수를 선정하여 선정된 매개변수를 고려한 전주의 공칭강도$(M_n)$를 설계기준의 공칭강도$(M_n)$와 비교 분석하였다.

뫼스바우어 효과를 통한 FeIn2S4에서의 Fe2+ 초미세 상호 작용 연구 (The Hyperfine Interaction for the FeIn2S4 by Mössbauer Spectroscopy)

  • 손배순;김삼진;김철성
    • 한국자기학회지
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    • 제17권1호
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    • pp.30-33
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    • 2007
  • [ $FeIn_2S_4$ ]를 제조하여 뫼스바우어 분광기, X-선 회절기, SQUID 자화율 측정기를 이용하여 결정학적 및 자기적 특성을 연구하였다. 결정구조는 역스피넬 구조로 In 이온은 각각 사면체 자리(A site)와 팔면체 자리(B site)에 동시에 존재하는데 비하여, Fe 이온은 팔면체 자리에만 존재하였다. Curie-Weiss 역자화율에 따른 유효자기모멘트는 $5.09{\mu}_B$였으며, 닐온도($N\'{e}el$ temperature)는 13 K였다. 이와 같이 낮은 닐온도는 팔면체 자리의 $Fe^{2+}(B)-S^2-Fe^{2+}(B)$의 초미세 상호작용이 약하기 때문인 것으로 설명되어진다. 전기사중극자 상호작용의 온도 의존성은 z-축에 따른 결정장 이론으로 설명되어진다.

Formation of surface mediated iron colloids during U(VI) and nZVI interaction

  • Shin, Youngho;Bae, Sungjun;Lee, Woojin
    • Advances in environmental research
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    • 제2권3호
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    • pp.167-177
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    • 2013
  • We investigated that removal of aqueous U(VI) by nano-sized Zero Valent Iron (nZVI) and Fe(II) bearing minerals (controls) in this study. Iron particles showed different U(VI) removal efficiencies (Mackinawite: 99%, green rust: 95%, nZVI: 91%, magnetite: 87%, pyrite: 59%) due to their different PZC (Point of Zero Charge) values and surface areas. In addition, noticeable amount of surface Fe(II) (181 ${\mu}M$) was released from nZVI suspension in 6 h and it increased to 384 ${\mu}M$ in the presence of U(VI) due to ion-exchange of U(VI) with Fe(II) on nZVI surface. Analysis of Laser-Induced Breakdown Detection (LIBD) showed that breakdown probabilities in both filtrates by 20 and 200 nm sizes was almost 24% in nZVI suspension with U(VI), while 1% of the probabilities were observed in nZVI suspension without U(VI). It indicated that Fe(II) colloids in the range under 20 nm were generated during the interaction of U(VI) and nZVI. Our results suggest that Fe(II) colloids generated via ion-exchange process should be carefully concerned during long-term remediation site contaminated by U(VI) because U could be transported to remote area through the adsorption on Fe(II) colloids.

Hydrophilic Modification of Poly(ethylene oxide) by UV Irradiation

  • Koo, Gwang-Hoe;Jang, Jin-Ho
    • 한국염색가공학회지
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    • 제21권5호
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    • pp.16-20
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    • 2009
  • Films of Poly(ethylene oxide), PEO, were modified to impart hydrophilicity via UV irradiation. The UV irradiation treatment produced new photo-oxidized groups of carbonyl and ether groups as indicated in ATR and ESCA analysis. It was found that water contact angle decreased from $15^{\circ}C$ to $10^{\circ}C$ and total surface energy of PEO increased from 54.2 mN/m to 76.6 mN/m with increasing UV energy, which was attributed to significant contribution of acid base interaction of the photo-oxidized PEO rather than nonpolar interaction originating from the dominant increase in Lewis acid parameter. The increased hydrophilicity and surface energy were also proved by the decreased water wetting time.

Interaction between a Blood Vessel-Inducing Protein Angiogenin and Its Binding Protein Actin

  • Chang, Soo-Ik;Paik, Seung-Bum;So, Seung-Ho;Ahn, Byung-Cheol
    • BMB Reports
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    • 제29권4호
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    • pp.353-358
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    • 1996
  • Bovine angiogenin (bAng) is a potent blood vessel inducing protein purified from cow In ilk. fluorescence spectroscopy has been used to study the interaction of bAng with actin in 50 mM Tris-HCl pH 7.5, and 1 mM $CaCl_2$ at $25^{\circ}C$. Actin contains four tryptophans but bAng contains no tryptophans. A 50% decrease in intrinsic fluorescence accompanied formation of the bAng/actin complex. By contrast, the interaction of RNase A, a homologous protein to bAng, with actin results in about 10% quenching of the fluorescence. Fluorescence titration experiments were performed by adding increasing concentrations of bAng (0~1.0 ${\mu}M$) to a constant concentration of actin (0.1 ${\mu}M$), and the dissociation constant $K_d$ for the bAng/actin complex and the stoichiometry n were measured as $20{\pm}1$ nM and $1.0{\pm}0.1$ respectively. These results suggest that the interaction between bAng with actin is specific and that quenching of actin fluorescence has occurred in the bAng/actin complex. The bAng binding sites of actin are discussed in the results of this study, and we propose that Trp-80 in the small domain of bovine actin is responsible for the bAng/actin binding.

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STUDIES ON THE HEPATOTOXICITY PRODUCED BY INTERACTION OF SEVERAL DRUGS CONTAINING AMINO GROUPS AND NITRITE

  • Moon, Hwa-Hwey;Kim, Pu-Young;Park, Han-Soo;Choi, Cheol-Hee
    • Toxicological Research
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    • 제3권2호
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    • pp.81-88
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    • 1987
  • Hepatotoxicity study of the nitrosamine produced by interaction between drugs containing amino groups and soduim nitrite was conducted. In the in vitro study, interaction of 32mM Promethazine HCL or Oxomemazine HCL with 200mM Sodium nitrite produced N-nitroso dimetylamine (NDMA) at 0.4% or 0.03%, respectively. When sodium nitrite was administered with Promethazine HCL or Oxomemazine HCL, trace of NDMA was detected from the gastric contents. After three days of consecutive administration of sodium nitrite with Promethazine HCL or Oxomemazine HCL, the levels of GOT, GPT and SDH in the serum of treated groups were significant higher than that of control group.

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Passively Q-switched Erbium Doped All-fiber Laser with High Pulse Energy Based on Evanescent Field Interaction with Single-walled Carbon Nanotube Saturable Absorber

  • Jeong, Hwanseong;Yeom, Dong-Il
    • Current Optics and Photonics
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    • 제1권3호
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    • pp.203-206
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    • 2017
  • We report a passive Q-switching of an all-fiber erbium-doped fiber laser delivering high pulse energy by using a high quality single-walled carbon nanotube saturable absorber (SWCNT-SA). A side-polished fiber coated with the SWCNT is employed as an in-line SA for evanescent wave interaction between the incident light and the SWCNT. This lateral interaction scheme enables a stable Q-switched fiber laser that generates high pulse energy. The central wavelength of the Q-switched pulse laser was measured as 1560 nm. A repetition rate frequency of the Q-switched laser is controlled from 78 kHz to 190 kHz by adjusting the applied pump power from 124 mW to 790 mW. The variation of pulse energy from 51 nJ to 270 nJ is also observed as increasing the pump power. The pulse energy of 270 nJ achieved at maximum pump power is 3 times larger than those reported in Q-switched all-fiber lasers using a SWCNT-SA. The tunable behaviors in pulse duration, pulse repetition rate, and pulse energy as a function of pump power are reported, and are well matched with theoretical expectation.

Device Coupling Effects of Monolithic 3D Inverters

  • Yu, Yun Seop;Lim, Sung Kyu
    • Journal of information and communication convergence engineering
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    • 제14권1호
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    • pp.40-44
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    • 2016
  • The device coupling between the stacked top/bottom field-effect transistors (FETs) in two types of monolithic 3D inverter (M3INV) with/without a metal layer in the bottom tier is investigated, and then the regime of the thickness TILD and dielectric constant εr of the inter-layer distance (ILD), the doping concentration Nd (Na), and length Lg of the channel, and the side-wall length LSW where the stacked FETs are coupled are studied. When Nd (Na) < 1016 cm-3 and LSW < 20 nm, the threshold voltage shift of the top FET varies almost constantly by the gate voltage of the bottom FET, but when Nd (Na) > 1016 cm-3 or LSW > 20 nm, the shift decreases and increases, respectively. M3INVs with TILD ≥ 50 nm and εr ≤ 3.9 can neglect the interaction between the stacked FETs, but when TILD or εr do not meet the above conditions, the interaction must be taken into consideration.