• Title/Summary/Keyword: Seed structure

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Size determination of Ecklonia cava for successful transplantation onto artificial seaweed reef

  • Kim, Young Dae;Shim, Jung Min;Park, Mi Seon;Hong, Jung-Pyo;Yoo, Hyun Il;Min, Byung Hwa;Jin, Hyung-Joo;Yarish, Charles;Kim, Jang K.
    • ALGAE
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    • v.28 no.4
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    • pp.365-369
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    • 2013
  • The objective of this study was to determine the optimal blade size and timing to transplant seed-stock of Ecklonia cava Kjellman onto the reef structure. We used the modified artificial stepped reef structure. A total of 14 units (3.0 m length ${\times}$ 3.5 m width ${\times}$ 1.1 m height) were deployed 7-8 m deep under the water to examine the optimal blade size and timing to transplant seed-stock of E. cava onto the structures. Sporophytes of E. cava <1 cm in length were all died within 1 month of transplantation. The blades of 5-10 cm in length which were transplanted in March 2007 survived and grew well on the artificial reefs. Growth rates of 5-10 cm size class were higher than those of longer blade sporophytes (20-30 cm size class, transplanted in April) while the survival rates showed no difference between the classes of blade size. Both classes of 5-10 and 20-30 cm in length grew until July, and a reduction in size had occurred in September. These results indicate the importance of the blade size of E. cava and timing for successful transplantation of the seaweed on artificial reef structures.

Synthesis and Characteristic of ${\epsilon}$-type Copper Phthalocyanine Used as Color Filter in LCD Panel (입실론 프탈로시아닌의 합성 및 특성에 대한 연구)

  • Kim, Jae Hwan;Kim, Song Hyuk;Kim, Seong Jin;Hong, Seong-Soo;Lee, Gun-Dae;Park, Seong Soo
    • Applied Chemistry for Engineering
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    • v.23 no.2
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    • pp.138-142
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    • 2012
  • The ${\epsilon}$ type copper phthalocyanine (${\epsilon}$-CuPc), called as a pigment blue 15 : 6, is a significant material to produce a blue pixel in LCD (Liquid Crystal Display) panel. In this study, ${\epsilon}$-CuPc sample was synthesized at various reaction conditions by applying the seed method using ${\epsilon}$-CuPc nanoparticles as a seed. Adequate synthetic conditions of the samples were selected by analyzing and comparing crystalline structure, crystalline purity, microstructure, and synthetic yield of the samples with ${\alpha}$ and ${\beta}$ crystalline CuPc samples. The chemical and crystalline structure of the samples were tested using FT-IR spectrometer and X-ray diffractometry, respectively. The shape of the particle was examined using field emission scanning electiron microscope while the thermal property was tested utilizing thermogravimetric analysis.

Discussion of the edge flame structure at the near flammability limits (가연한계 영역에서의 에지 화염 구조 및 고찰)

  • Lee, Min Jung;Jung, Yongjin;Kim, Nam Il
    • 한국연소학회:학술대회논문집
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    • 2015.12a
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    • pp.245-246
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    • 2015
  • In this study, the structure of a edge flame near the flammability limits was explored through several paths approaching the combustion limits of a non-premixed flame: i.e., increase of fuel dilution ratio (FDR), reduction of mean flow velocity and variation of gravity effect. As a result, a unique interesting flame structure was discovered; i.e., a diffusion flame branch was enclosed by two asymmetric premixed flame branches. These structures have been compared for various fuels. Conclusively, each fuel has different flame structure and the meaning of this structure was discussed concerned about our understanding of laminar flame structures.

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SOI CMOS image sensor with pinned photodiode on handle wafer (SOI 핸들 웨이퍼에 고정된 광다이오드를 가진 SOI CMOS 이미지 센서)

  • Cho, Yong-Soo;Choi, Sie-Young
    • Journal of Sensor Science and Technology
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    • v.15 no.5
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    • pp.341-346
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    • 2006
  • We have fabricated SOI CMOS active pixel image sensor with the pinned photodiode on handle wafer in order to reduce dark currents and improve spectral response. The structure of the active pixel image sensor is 4 transistors APS which consists of a reset and source follower transistor on seed wafer, and is comprised of the photodiode, transfer gate, and floating diffusion on handle wafer. The source of dark current caused by the interface traps located on the surface of a photodiode is able to be eliminated, as we apply the pinned photodiode. The source of dark currents between shallow trench isolation and the depletion region of a photodiode can be also eliminated by the planner process of the hybrid bulk/SOI structure. The photodiode could be optimized for better spectral response because the process of a photodiode on handle wafer is independent of that of transistors on seed wafer. The dark current was about 6 pA at 3.3 V of floating diffusion voltage in the case of transfer gate TX = 0 V and TX=3.3 V, respectively. The spectral response of the pinned photodiode was observed flat in the wavelength range from green to red.

Studies on Incompatibility in Interspecific Hybrid Between Panax ginseng C. A. Meyer and Panax quinquefolium L. (고려인삼과 미국삼의 종간 잡종식물체 불화합성에 관한 연구)

  • 이성식;정열영
    • Journal of Ginseng Research
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    • v.21 no.2
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    • pp.85-90
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    • 1997
  • This study was carried out to clarify the cause of incompatibility in interspecific hybrid plant between Panax ginseng and p. quinquefolium. The floral structure of F,(p.g. x p.q.) hybrid was normal because the redundant anther was 0.2 mm longer than pistil in Fl hybrid and the size and structure of redundant carpel in F, hybrid were similar to P. ginseng and p. quiquefolium Pollens of $F_1$ hybrid did not germinate on stigma of P-quinquefolium but germinated well on stigma of P. ginseng. Pollen tube was able to penetrate styles completely and seed harvest rate was 16.8% in field. However on stigma of $F_1$ hybrid, Pollen did not germinate when P. ginseng was used as male Parent. In addition, the growth of pollen tube was halted on style and seed was not set when P qlfinquefoEi2a was used as male Parent. These suggest that the inhibitor of pollen germination present on stigma caused $F_1$ hybrid sterility. It took 5 hours for pollen grains to germinate, 12 hours to arrive at in trance of ovule, 16 hours to penetrate micropyles in Panax ginseng.

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Synthesis and Exploitation in Solar Cells of Hydrothermally Grown ZnO Nanorods Covered by ZnS Quantum Dots

  • Mehrabian, Masood;Afarideh, Hossein;Mirabbaszadeh, Kavoos;Lianshan, Li;Zhiyong, Tang
    • Journal of the Optical Society of Korea
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    • v.18 no.4
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    • pp.307-316
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    • 2014
  • Improved power conversion efficiency of hybrid solar cells with ITO/ZnO seed layer/ZnO NRs/ZnS QDs/P3HT/PCBM/Ag structure was obtained by optimizing the growth period of ZnO nanorods (NRs). ZnO NRs were grown using a hydrothermal method on ZnO seed layers, while ZnS quantum dots (QDs) (average thickness about 24 nm) were fabricated on the ZnO NRs by the successive ionic layer adsorption and reaction (SILAR) technique. Morphology, crystalline structure and optical absorption of layers were analyzed by a scanning electron microscope (SEM), X-ray diffraction (XRD) and UV-Visible absorption spectra, respectively. The XRD results implied that ZnS QDs were in the cubic phase (sphalerite). Other experimental results showed that the maximum power conversion efficiency of 4.09% was obtained for a device based on ZnO NR10 under an illumination of one Sun (AM 1.5G, $100mW/cm^2$).

Ecological Studies on the Distribution, Structure and Maintenance Mechanism of Berchemia berchemiaefolia Forest (망개나무林의 分布, 構造 및 維持機作)

  • Kang, Sang-Joon;Hong-Eun Kim;Chang-Seok Lee
    • The Korean Journal of Ecology
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    • v.14 no.1
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    • pp.25-38
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    • 1991
  • Berchemia berchemiaefolia is a native a native rare plant which has been designating as the Natural Monument, No. 266, since 1980. The floristic composition, population structure and maintenance mechanism of the Berchemia berchemiaefolia forest were investigated in conjunction with the habitat consisted of the block field or screes. Through the present study, the authors found a new habitat of Berchemia berchemiaefolia in the northeastern slope on Mt. Kumdansan located at Hajeok-ri, Cheongcheon-myeon, Koesan-gun, chungbuk province. Gravels consisted of the block field belonged to granule, pebble and cobble as the range of grain size, $\Phi$=-1.5~6.6 values. The tree layer of Berchemia berchemiaefolia community was mainly composed of Quercus variabilis, Pinus densiflora and Q. serrata including Berchemia berchemiaefolia and of this community were similar to that of Q. variabilis. By the age distribution, it was considered that the community was a discontinued one as the pattern of distribution was a normal distribution type(N type). Phenological cycle including leafing, blooming and seed-bearing period between both sites of block field and valley or close canopy showed some differences. The seed production of Berchemia berchemiaefolia was 8, 655, 000 seeds/ha/year, but only 406, 000 seeds/ha/year of them were developed as saplings, and only 4 saplings were developed to mature trees.

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New Seed Detection by Shape Analysis for Construction of Vascular Structures

  • Shim, Hack-Joon;Lee, Hyun-Joon;Yun, Il-Dong;Lee, Sang-Uk
    • Journal of Biomedical Engineering Research
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    • v.31 no.6
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    • pp.427-433
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    • 2010
  • Although tracking methods are efficient and popular for vessel segmentation, they require a seed to initiate an instance of tracking. In this paper, a new method to detect new seeds for tracking of arterial segments from CT angiography (CTA) and to construct a vascular structure is proposed. The proposed algorithm is based on shape analysis of connected components in a volume of interest around a vessel segment which was already extracted by tracking. The eigenvalues of the covariance matrix are used as the shape features for detection. The experimental results on actual clinical data showed that the results totally revealed the arterial tree not hindered by bone or veins. In visual comparison to a method which combines registration and subtraction of both pre-contrast and post-contrast CT volumes, the proposed method produced comparable results to the reference method and were confirmed of its feasibility for clinical use of reducing the cost and burden of patients.

Improvement of dielectric and interface properties of Al/CeO$_2$/Si capacitor by using the metal seed layer and $N_2$ plasma treatment (금속씨앗층과 $N_2$ 플라즈마 처리를 통한 Al/CeO$_2$/Si 커패시터의 유전 및 계면특성 개선)

  • 임동건;곽동주;이준신
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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    • 2002.07a
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    • pp.326-329
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    • 2002
  • In this paper, we investigated a feasibility of cerium oxide(CeO$_2$) films as a buffer layer of MFIS(metal ferroelectric insulator semiconductor) type capacitor. CeO$_2$ layer were Prepared by two step process of a low temperature film growth and subsequent RTA (rapid thermal annealing) treatment. By app1ying an ultra thin Ce metal seed layer and N$_2$ Plasma treatment, dielectric and interface properties were improved. It means that unwanted SiO$_2$ layer generation was successfully suppressed at the interface between He buffer layer and Si substrate. The lowest lattice mismatch of CeO$_2$ film was as low as 1.76% and average surface roughness was less than 0.7 m. The Al/CeO$_2$/Si structure shows breakdown electric field of 1.2 MV/cm, dielectric constant of more than 15.1 and interface state densities as low as 1.84${\times}$10$\^$11/ cm$\^$-1/eV$\^$-1/. After N$_2$ plasma treatment, the leakage current was reduced with about 2-order.

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Microstructure and Trapped Magnetic Field of Multi-Seeded Single Domain YBCO

  • Bierlich, J.;Habisreuther, T.;Litzkendorf, D.;Zeisberger, M.;Gawalek, W.
    • Progress in Superconductivity
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    • v.8 no.1
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    • pp.8-15
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    • 2006
  • The size of the superconducting domains and the critical current density inside these domains have to be enhanced for most of cryomagnetic applications of melt-textured YBCO bulks. To enlarge the size of the domains we studied the multi-seeding technique based on a well-established procedure for preparing high quality YBCO monoliths using self-made SmBCO seeds. The distance between the seeds was optimised as a result of the investigation of the effects of various seed distances on the characteristics of the grain boundary Junctions. The influences of a-b plane intersections and c-axis misalignments were researched. Thereby, a small range of tolerance of the misorientations between the seed crystals was found. Field mapping was applied to control the materials quality and the superconductor's grain structure was investigated using polarisation microscopy. YBCO function elements with iou. seeds in a line and an arrangement of making type (100)/(100) and (110)/(110) boundary junctions, respectively, were processed. The trapped field profile in both sample types shows single domain behaviour. To demonstrate the potential of the multi-seeding method a ring-shaped sample was processed by placing sixteen seeds in a way to make both (100)/(100) and (110)/(110) grain junctions at the same time. The results up to now are very promising to prepare large single domain melt-textured YBCO semi-finished products in complex shapes.

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