• Title/Summary/Keyword: ${\pi}?{\pi}$ interaction

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Development of Smart Mirror System based on the Raspberry Pi (Raspberry Pi를 이용한 스마트 미러 개발)

  • Lin, Zhi-Ming;Kim, Chul-Won
    • The Journal of the Korea institute of electronic communication sciences
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    • v.16 no.2
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    • pp.379-384
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    • 2021
  • With people's continuous research and exploration in the field of artificial intelligence, more relatively mature artificial intelligence technology is applied in people's daily life. Mirrors are the most commonly used daily necessities in life, and it should be applied to artificial intelligence. The research results of this paper show that the smart mirror designed based on the raspberry pi displays weather, temperature, greetings, and has a human-mirror interaction function. The research method of this paper uses the Raspberry pi 3B + as the core controller and Google Assistant as the intelligent control. When connected to the network via Raspberry Pi's own WiFi, the mirror can automatically display and update time, weather and news information features. You can wake up the Google Assistant using keywords, then control the mirror to play music, remind the time, It implements the function of smart mirror voice interaction. Also, all the hardware used in this study is modular assembly. Later, it is convenient for user to assemble by himself later. It is suitable for market promotion at an affordable price.

MO Studies of Configuration and Conformation (XV). Through-Space and Through-Bond Interactions In Ethylene Diamine (배치와 형태에 관한 분자궤도론적 연구 (제15보). 에틸렌 디아민의 Through-Space 및 Through-Bond 상호작용)

  • Ikchoon Lee;Chang Kook Sohn;Chang Hyun Song
    • Journal of the Korean Chemical Society
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    • v.26 no.2
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    • pp.65-72
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    • 1982
  • STO-3G level computations were performed on n-propylamine, n-propylamine radical and cis-and trans-ethylene diamines in order to investigate structural contributions of (n${\pi}$/m) and (n-${\sigma}^*$) structures to the energy variations accompanying the conformational changes. It was found that (5${\pi}$/5) and (4${\pi}$/4) structures had attractive and repulsive nonbonded interactions, respectively, which were approximately additive. anti(n-${\sigma}^*$) structures had more stabilzing hyperconjugative interactions than syn(n-${\sigma}^*$) structures, but due to the large internuclear repulsion the net effect was destabilizing inthe former in contrast with the net stabilizing contribution in the latter. Moreover it was found that the stabilizing ${\pi}$-nonbond structure, (5${\pi}$/5) was always cooperatively reinforced by the more stabilizing anti(n-${\sigma}^*$) interaction, whereas the destabilizing (4${\pi}$/4) structure was accompanied by the less stabilizing syn(n-${\sigma}^*$) interaction. This type of cooperativity was found general through-bond interaction of the terminal lone pair lobes split the energy levels into two, $n_+ = \frac{1}{\sqrt{2}}(n_1 + n_2)$ and $n_- = \frac{1}{\sqrt{2}}(n_1 - n_2)$, the latter being the lower level, which can be shown using simple overlap patterns of the two lobes with a common vicinal ${\sigma}^*$ orbital.

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Preparation of a New Chiral Stationary Phase Bearing Both $\pi$-Acidic and -Basic Sites from (S)-Naproxen for the Liquid Chromatographic Resolution of Enantiomers

  • Hyun Myung Ho;Jin Jong Sung;Ryoo Jae-Jeong;Jyung Kyung Kyu
    • Bulletin of the Korean Chemical Society
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    • v.15 no.6
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    • pp.497-502
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    • 1994
  • A new chiral stationary phase (CSP) for the liquid chromatographic resolution of enantiomers was prepared from (S)-naproxen and 3,5-dinitroaniline. The 6-alkoxy-2-naphthyl group of the CSP was presumed to act as a ${\pi}$-basic interaction site for resolving ${\pi}$-acidic racemates while the 3,5-dinitroanilide group of the CSP was presumed to play a role as a ${\pi}$-acidic interaction site for resolving ${\pi}$-basic racemates. From the chromatographic resolution trends of N-alkylamide derivatives of ${\alpha}$-arylalkylamines on the CSP prepared, the chiral recognition mode involving the intercalation of the amide alkyl chain of the less retained enantiomers between the connecting tethers of the CSP was proposed.

Theoretical Study of the Conformation of Cis Carbene-Olefin Transition Matal Complexes (시스 카벤-올레핀 전이금속 착물들의 형태에 대한 이론적 연구)

  • Seong-Kyu Park;Ill-Doo Kim;Joon-Tae Kim;Chang-Jin Choi;Young-Gu Cheun
    • Journal of the Korean Chemical Society
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    • v.36 no.6
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    • pp.802-811
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    • 1992
  • The conformations of several carbene-olefin-transition metal complexes[$(CO)_4M$-(CHX)olefin] (X: $OCH_3,\;NHCH_3,\;SCH_3$, M: C, Mo, W) have been studied by means of Extend Huckel calculations. In the case of $d^6$ transition metal octahedral complexes, it is shown that the two main factors which determine the optimal conformation are metal-to-ligand back-donation and direct ligand-ligand interaction at the metal, but the ligand-ligand interaction dominates the situation for a metal that is coordinated to $\pi$ acceptor ligands and to $\pi$ donor group on the carbene. The relative amounts of both factors depend strongly on the electronic nature of the ligands at the metal. The greater electron donating ability of nitrogen stabilizes amino-substituted carbene complexes compared with their alkoxyl substituted analogues. This interaction is optimal when the $\pi$ systems of the carbene and olefin are coplanar. The introduction of the $\pi$ donor group on the carbene carbon increases also the importance of the ligand-ligand interaction.

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Annealing effect on LC alignment using the photo-depolymerization reaction (광분해 반응을 이용한 액정배향에서의 어닐링 효과)

  • Kim, Hyung-Kyu;Yu, Mun-Sang;Seo, Dae-Shik
    • Proceedings of the KIEE Conference
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    • 1999.07d
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    • pp.1762-1764
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    • 1999
  • We investigated the annealing effect on generating pretilt angle and aligning liquid crystal (LC) using the photo-depolymerization reaction in this study. In case of rubbing polyimide (PI) surface with the side chain, pretilt angle tends to increase with increasing the annealing time. It is considered because the steric interaction is increased by annealing which cause the side chain to come back to original position. For obliquely irradiating ultraviolet (UV) light on PI surface, pretilt angle shows to $0^{\circ}$ and is increased by annealing. The pretilt angle in rubbed PI surface is much higher than in photo-aligned PI surface. It is attributed to the steric interaction and the number of LC molecular arrangement on azimuthal direction. In addition. in case of obliquely irradiating UV light on PI surface. it showed LC alignment to increase by annealing. It can be regarded due to the fact that the re-alignment of LC molecule is improved to residual polymer direction by annealing.

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Phosphoinositide turnover in Toll-like receptor signaling and trafficking

  • Le, Oanh Thi Tu;Nguyen, Tu Thi Ngoc;Lee, Sang Yoon
    • BMB Reports
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    • v.47 no.7
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    • pp.361-368
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    • 2014
  • Lipid components in biological membranes are essential for maintaining cellular function. Phosphoinositides, the phosphorylated derivatives of phosphatidylinositol (PI), regulate many critical cell processes involving membrane signaling, trafficking, and reorganization. Multiple metabolic pathways including phosphoinositide kinases and phosphatases and phospholipases tightly control spatio-temporal concentration of membrane phosphoinositides. Metabolizing enzymes responsible for PI 4,5-bisphosphate (PI(4,5)P2) production or degradation play a regulatory role in Toll-like receptor (TLR) signaling and trafficking. These enzymes include PI 4-phosphate 5-kinase, phosphatase and tensin homolog, PI 3-kinase, and phospholipase C. PI(4,5)P2 mediates the interaction with target cytosolic proteins to induce their membrane translocation, regulate vesicular trafficking, and serve as a precursor for other signaling lipids. TLR activation is important for the innate immune response and is implicated in diverse pathophysiological disorders. TLR signaling is controlled by specific interactions with distinct signaling and sorting adaptors. Importantly, TLR signaling machinery is differentially formed depending on a specific membrane compartment during signaling cascades. Although detailed mechanisms remain to be fully clarified, phosphoinositide metabolism is promising for a better understanding of such spatio-temporal regulation of TLR signaling and trafficking.

A Study on Alignment of Nematic Liquid Crystal by Using Slanted Non-polarized Ultraviolet Light Irradiation on Polyimide Film (폴리이미드막표면위에 경사진 자외선 조사를 이용한 네마틱 액정의 배향에 관한 연구)

  • 서대식;황율연;이보호
    • Electrical & Electronic Materials
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    • v.10 no.5
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    • pp.461-466
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    • 1997
  • In this paper, we developed the new non-rubbing liquid crystal (LC) alignment techniques in the cell with slanted non-polarized ultraviolet (UV) light irradiation on polyimide (PI) film. It is shown that the uniform alignment for nematic (N) LC is obtained by using slanted non-polarized UV light irradiation on PI surface. We successfully obtained that the pretilt angle of NLC is generated about 3.3 degree in the cell with slanted non-polarized UV light irradiation with 70 degree on PI surface, for the first time. It is considered that the pretilt angle generation in NLC is attributed to interaction between the LC molecular and the PI, which is broken the polymer by slanted non-polarized UV irradiation. Therefore, we concluded that the uniform LC alignment is attributed to anisotropic dispersion force due to photo depolymerization with slanted non-polarized UV light irradiation on PI surface.

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