• 제목/요약/키워드: Planar.

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Analyzing Co-planar PCBs in Food by HRGC/HRMS with Isotopic Dilution Method (동위원소희석법 HRGC/HRMS에 의한 식품 중 Co-planar PCBs 분석)

  • Choi, Dongmi;Suh, Junghyuck;Kim, Minjung;Hong, Mooki;Kim, Changmin;Song, Insang
    • Analytical Science and Technology
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    • v.16 no.4
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    • pp.325-332
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    • 2003

  • To analyze co-planar PCBs in food, the isotopic dilution method by high resolution gas chromatography/high resolution mass spectrometry was applied. Among 209 PCB congeners, 12 congeners (#77, #81, #126, #169, #105, #114, #118, #123, #156, #157, #167 and #189) were chosen as target compounds that were toxic congeners re-assessed by WHO in 1998. Milk and milk products including cheese and butter were collected as food samples. Samples were homogenized, spiked with the known amount of the standard mixture and extracted. After extraction, extracts were cleaned up by sulfuric acid impregnated silica gel, purified on silica gel and alumina column chromatography and then analyzed by HRGC/HRMS. As results, the overall recoveries were ranged from 83% to 106% and the limit of detection was about 0.1 pg/g at signal/noise>3. Levels of targets in the selected food samples were 0.001~0.107 pgWHO-TEQ/g.

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Seismic behavior of steel reinforced concrete (SRC) T-shaped column-beam planar and 3D hybrid joints under cyclic loads

  • Chen, Zongping;Xu, Jinjun;Chen, Yuliang;Xue, Jianyang
    • Earthquakes and Structures
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    • v.8 no.3
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    • pp.555-572
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    • 2015

  • This paper presents an experimental study of three two-dimensional (2D/planar) steel reinforced concrete (SRC) T-shaped column-RC beam hybrid joints and six 3D SRC T-shaped column-steel beam hybrid joints under low cyclic reversed loads. Considering different categories of steel configuration types in column cross section and horizontal loading angles for the specimens were selected, and a reliable structural testing system for the spatial loading was employed in the tests. The load-displacement curves, carrying capacity, energy dissipation capacity, ductility and deformation characteristics of the test subassemblies were analyzed. Especially, the seismic performance discrepancies between planar hybrid joints and 3D hybrid joints were intensively compared. The failure modes for planar loading and spatial loading observed in the tests showed that the shear-diagonal compressive failure was the dominating failure mode for all the specimens. In addition, the 3D hybrid joints illustrated plumper hysteretic loops for the columns configured with solid-web steel, but a little more pinched hysteretic loops for the columns configured with T-shaped steel or channel-shaped steel, better energy dissipation capacity & ductility, and larger interlayer deformation capacity than those of the planar hybrid joints. Furthermore, it was revealed that the hysteretic loops for the specimens under $45^{\circ}$ loading angle are generally plumper than those for the specimens under $30^{\circ}$ loading angle. Finally, the effects of steel configuration type and loading angle on the seismic damage for the specimens were analyzed by means of the Park-Ang model.

  • https://doi.org/10.12989/eas.2015.8.3.555 인용 KSCI

Frequency Characteristics of 2-Layer Spiral Planar Inductor (2층 나선형 박막 인덕터의 주파수 특성)

  • Kim, Jae-Wook;Ryu, Chang-Keun
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.12 no.9
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    • pp.4101-4106
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    • 2011

  • In this study, we propose that the structures of 2-layer spiral planar inductors have a lower spiral coil and via increasing inductance in limited possession are and confirm the frequency characteristics. The structures of inductors have Si thickness of $300{\mu}m$, $SiO_2$ thickness of $7{\mu}m$. The width of Cu coils and the space between segments have $20{\mu}m$, respectively. The number of turns of coils have 3. The performance of spiral planar inductors was simulated to frequency characteristics for inductance, quality-factor, SRF(Self- Resonance Frequency) using HFSS. The 2-layer spiral planar inductors have inductance of 3.2nH over the frequency range of 0.8 to 1.8 GHz, quality-factor of maximum 8.2 at 2.5 GHz, SRF of 5.8 GHz. Otherwise, 1-layer spiral planar inductors have inductance of 1.5nH over the frequency range of 0.8 to 1.8 GHz, quality-factor of maximum 18 at 8 GHz, SRF of 19.2 GHz.

  • https://doi.org/10.5762/KAIS.2011.12.9.4101 인용 PDF KSCI