• Title/Summary/Keyword: 반점화

Search Result 82, Processing Time 0.031 seconds

Structure of Hydroxy-bisbenzoyloxy-allyloxycalix[4]arene (Hydroxy-bisbenzoyloxy-allyloxycalix[4]arene의 구조)

  • Lee, Bo-Hyeong;Jo, Seon-Hui;Park, Yeong-Ja
    • Korean Journal of Crystallography
    • /
    • v.8 no.2
    • /
    • pp.111-118
    • /
    • 1997
  • The structrue of hydroxy-bisbenzoyloxy-allyloxycalix[4]arene (C45H36O6) has been determined by X-ray crystallography. The crystals are monoclinic, space group P21, unit cell constants a=11.045(3), b=33.545(2) c=10.319(4)Å, β=113.86(2)˚, Z=4, V=3496.0(1.8) Å3, DC=1.28 gcm-3. The intensity data were collected on an Enraf-Noninus CAD-4 Diffractometer with a graphite monochromated Mo-Kα radiation. The structure was solved by direct method and refined by full-matrix least-squares calculations to a final R value of 0.076 for 2945 observed reflections. Two independent enantiomeric molecules are crystallized in a 1:1 racemate mixture. They have the flattened cone conformation with the flattening hydroxy1 pheny1 rings. There is an intramolecular hydrogen bond in both molecules.

  • PDF

Structure of Tetrapropionyloxycalix[4]arene (Tetrapropionyloxycalix[4]arene의 구조에 관한 연구)

  • 박영자;김현희
    • Korean Journal of Crystallography
    • /
    • v.6 no.2
    • /
    • pp.80-87
    • /
    • 1995
  • The structure of Tetrapropionyloxycalix[4]arene(C40H40O8) has been studied by X-ray diffraction method. The crystal is monoclinic a=13.921(3), b=13.552(2), c=19.840(5)Å, β=110.38(2)°, Z=4 T=297K, Dc=1.23gcm-3, F(000)=1376, Systematic absences : hkl none, h0l : h+l=2n, 0k0: k=2n define space group P21/n. The structure was solved by direct method and refined by full-matrix least-squares methods to final R of 0.06 for 2514 observed reflections. The macrocycle exists in partial cone conformation. Three propionyl groups direct toward the exterior of the macrocycle cavity.

  • PDF

Multi-Texture Image Segmentation Using Gabor Filter (가보필터를 이용한 복합무늬 영상 분할)

  • 송석진;김현석;남기곤
    • Proceedings of the Korea Institute of Convergence Signal Processing
    • /
    • 2001.06a
    • /
    • pp.233-236
    • /
    • 2001
  • 본 논문에서는 가보필터를 이용한 복합무늬영상을 분할하는 알고리즘을 제안하였다. 영상을 분할하는데 있어 목적에 따라 다양한 방법이 있다. 그중 무늬(texture) 특징을 기반으로 영상을 분할하는 방법 중 가장 많이 알려진 것이 가보 필터이다. 이 필터는 탁월한 영상분할 결과를 얻을 수 있으나, 필터구현이 어렵다는 단점을 가지고 있다. 가보필터의 이 같은 반점인 복잡한 필터 처리를 단순히 하기 위해 전처리과정에서 필터를 영상에 맞게 선택하여 사용하였고, 영상 분할에 있어서도 histogram을 이용한 영상 분할을 수행함으로써 처리과정을 단순화 시켰다. 그 결과 간단한 알고리즘으로 빠른 수행이 이루어졌으며 좋은 결과를 가져올 수 있었다.

  • PDF

The Land Use Change and the Desertification in the East Inner Mongolia, China - A Case Study on Horqin Desert - (중국 내몽고 동부지역의 토지이용 변화와 사막화 -커얼친 사지의 사례 -)

  • Lee Kang-Won
    • Journal of the Korean Geographical Society
    • /
    • v.40 no.6 s.111
    • /
    • pp.694-715
    • /
    • 2005
  • I examine in this paper the change of land use and the development of desertification in Horqin desert, east Inner Mongolia, China. The change of land use in this area can be summarized as the increase of agricultural field and intensive livestock farming. The agriculture and livestock farming in semi-arid area such as Horqin desert raised the problem in the management and use of water and vegetation. This problem led to desertification. The types of development of desertification in this area could be classified as follows: the mobile sand dune extension, the riverside shifting sand flat extension, the shifting sand speck extension around settlements, and the shifting sand speck extension in agricultural Held and grassland. There have been political or social movements such as the Great Leap Forward, the Cultural Revolution and the Reform and Open Policy in the background of land use change and desertification. Specially, the Great Leap Forward and the Cultural Revolution played an important role in the land use change and desertification in this area. Since 1990s, there has been some kind of policy in the control of desertification. However, it is necessary for the controling desertification of this area to consider the globalization and marketization, the survival and profit of peasants and livestock farmers, and the disturbrd and fixed population and land use structure in this area since 1949.

Resistance Evaluation of Several Turfgrass Species and Graminious Crop Species against Rhizoctonia cerealis and Typhula incarnata under Controlled Conditions (주요 잔디류와 화본과 식량 밭작물의 황색마름병원균 및 설부소립균핵병원균에 대한 저항성 평가)

  • Chang, Seog-Won;Chang, Tae-Hyun;Yang, Geun-Mo;Choi, Joon-Soo;Rho, Yong-Taek
    • Asian Journal of Turfgrass Science
    • /
    • v.24 no.1
    • /
    • pp.9-15
    • /
    • 2010
  • During 2008~2009 winter season, yellow patch and gray snow mold occurred on turfgrass plants in golf courses in Kangwon and Jeonbuk provinces, respectively. The fungi associated with the diseases were identified as Rhizoctonia cerealis Van der Hoeven and Typhlua incarnata Lasch ex Fr., based on the morphological characteristics of hyphae and sclerotia. R. cerealis and T. incarnata were pathogenic to most turfgrass and crop species tested. R. cerealis infected crown, stem and leaf tissue of the host plants, and the symptom was light yellow circular patch. Individual infected leaf near the margin of patch developed red color first and finally turn brown. The symptoms caused by gray snow mold pathogen are water-soaked spots, and became a watery soft rot. Infection parts became yellow and then turned brown followed by death of the whole plant. White mycelia were developed on higher petioles, leaves, and on soil where these plant parts lay, and black sclerotia of variable size and shape formed in the mycelial mass. All isolates tested were pathogenic on most turfgrass and crop plants, and significantly different in aggressiveness. Disease severity increased with longer snow cover days on target plants, suggesting that disease severity was expressed over snow cover days. There were significant differences in disease severity among the graminious species, and among cultivars within each species, indicating varying levels of susceptibility to R. cerealis and T. incarnata.

The Crystal Structure of Bis(ethylenediamine)palladium(II)-Bis(oxalato)palladate(II) (Bis(ethylenediamine)palladium(II)-Bis(oxalato)palladate(II)의 결정구조)

  • Go, Gi-Yeong;Nam, Gung-Hae;Han, Sang-Gon
    • Korean Journal of Crystallography
    • /
    • v.9 no.1
    • /
    • pp.71-76
    • /
    • 1998
  • Crystal structure of Bis(ethylenediamine)palladium(II)-Bis(oxalato)palladate(II0 has been determined by X-ray crystallography. Crystal data : (Pd(C2H8N2)2.Pd(C2O4)2), Fw=509.04, Monocline, Space Group P21/c (no=14), a=6.959(2), b=13.506(2), c=15.339(2) Å, β=99.94(3), Z=4, V=1420 Å3, Dc=2.380 gcm-3, μ=25.46cm-1, F(000)=992. The intensity data were collected with Mo-Kα radiation (λ=0.7107 Å) on an automatic four-circle diffractometer with a graphite monochromater. The structure was solved by Patterson method and refined by full matrix least-square methods using unit weights. The final R and S values were R=0.021, Rw=0.030, Rall=0.032 abd S=2.1 for 1472 observed reflections. The essentially planar complex anions form diade of interplanar distances of 3.41 Å and their diads are stacked along aaxis with interplanar separation of 3.44 Å.

  • PDF

Structure of Cholesteryl Crotonate (Cholesteryl crotonate의 구조)

  • 박영자;신정미
    • Korean Journal of Crystallography
    • /
    • v.13 no.1
    • /
    • pp.21-24
    • /
    • 2002
  • The crystal structure of cholesteryl crotonate was investigated by X-ray diffraction. Crystallo-graphic data for the title compound: P2₁, a = 13.446(4) , b = 11.802(3) , c = 18.782(5) , β = 103.99(2)°, Z = 4. Reflections were collected with an Enraf-Nonius CAD-4 diffractometer equipped with a graphite monochromator. The structure was solved by direct methods and refined by least-squares analyses. The final R value was 0.092 for 1604 reflections. The cholesterol fragment of the title compound were in good agreement with those for related cholesterol derivatives. The molecules were stacked in clearly separated layers. At the center of the layers, there were cholesterol-cholesteryl interactions between the symmetry-related A molecules and the cholesteryl-C(17) side chain of B molecules. There were also interactions between the C(17) side chain of A molecules and the crotonate chains off and B molecules in the interface region between layers. The crystal structure of the title compound turned out to be isostructural with those of cholesteryl ethylcarbonate, cholesteryl propylcarbonate, and cholesterol crotylcarbonate. The crystals show the liquid crystalline state having the cholesteric phase.

Halo Spot Symptom Induced by Oviposition of Frankliniella occidentalis on Grape Fruits: Molecular Diagnosis by a Species-specific DNA Amplification and Microscopic Characterization of the Symptom (꽃노랑총채벌레 산란에 의한 포도 과피 달무리 반점: 종 특이적 분자진단법을 이용한 종동정과 반점 증상의 형태적 특징)

  • Ahn, Seung-Joon;Cho, Myoung Rae;Park, Cheol Hong;Kang, Taek Jun;Kim, Hyung Hwan;Kim, Dong-Hwan;Yang, Chang Yeol
    • Korean journal of applied entomology
    • /
    • v.53 no.3
    • /
    • pp.281-286
    • /
    • 2014
  • In grape vineyards, whitish spots in a cloud shape have been often observed on the fruit surface recently. However, the cause of the halo spot symptom was unknown, hindering countermeasures to be properly designed for the control. A small hole in the middle of the formless halo spot remained as a scar formed by oviposition of the thrips. It became later a suberized scab, which is separated from the epidermal cells on the surface either to be retained on or to be detached from it as time proceeds. Such a symptom is distinguished from the feeding damages caused by thrips or true bugs occurring on the grape fruits. With DNA extracted from the egg-shell found in the hole, molecular diagnosis by amplifying an ITS2 region with universal primers and subsequently digesting the PCR product by an restriction enzyme (RsaI) revealed that the egg was laid by Frankliniella occidentalis. In addition, a mitochondrial COI sequence confirmed that the halo spot symptom was formed by its oviposition. This study provides accurate information on the peculiar damage symptom caused by oviposition of F. occidentalis that could be useful in the control strategies for this pest in vineyards.

An Asiatic Hybrid Lily 'Apricot King' with Unspotted Light Orange Petals (무반점 연한 오렌지색 아시아틱나리 'Apricot King' 육성)

  • Rhee, Hye Kyung;Cho, Hae Ryong;Lim, Jin Hee;Kim, Mi Seon;Park, Sang Kun;Joung, Hyang Young
    • FLOWER RESEARCH JOURNAL
    • /
    • v.17 no.1
    • /
    • pp.36-39
    • /
    • 2009
  • An Asiatic lily cultivar 'Apricot King' was bred in 2007 at National Horticultural Research Institute (NHRI), Rural Development Administration (RDA), Suwon, Korea. The cross was made in 2002 between Asiatic lily 'Orlando', a light orange colored cultivar, and 'Corrida', yellow and pink colored cultivar. Preliminarily selection was done as 'A04-72' in 2004. Multiplication and bulb formation, and characteristic tests were conducted from 2005 to 2006. The evaluation of this line was performed and named as 'Wongyo C1-84' in 2007 that was registered as 'Apricot King' to the registration office of Korea Seed & Variety Service. 'Apricot King' flowers at the end of June and grows average 121.6 cm. It flowers upward-facing, dark green throat and yellow orange (RHS 20A) with the size of flower 17.9 cm. Mean petal length and width is 12.8 cm and 3.7 cm, respectively. Leaves are 16.1 cm long and 2.1 cm wide. It shows light orange stigma and pollen. The weight and size of bulb is 64.2 g and 17.6 cm, respectively. For long-term storage, bulbs can be stored under -1 to $-2^{\circ}C$ for year-round forcing.

Synthesis and Crystal Structure of Nickel(II) Complex of trans-1,2-Diaminocyclohexane (Nickel(II) trans-1,2-Diaminocyclohexane 착물의 합성 및 결정 구조)

  • ;;;;dward R. T. Tiekink
    • Korean Journal of Crystallography
    • /
    • v.12 no.2
    • /
    • pp.88-91
    • /
    • 2001
  • The complex [NiL₃]Cl₂·3H₂O (1) (L=trans-1,2-diaminocyclohexane) has been synthesized and characterized by X-ray crystallography. The compound 1 crystallizes in the cubic space group P2₁3, with a=13.830(1) Å, V=2645.9(2) ų, Z=4, R₁(wR₂) for 1500 observed reflections of [I> 2σ(I)] was 0.0766 (0.2068).

  • PDF