• Korean Journal of Environmental Agriculture
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• v.20 no.3
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• pp.186-191
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• 2001

Recently, petroleum spray oil(PSO) has been used to control key pests in integrated pest management (IPM) of citrus and other orchards in Australia and USA. In order to clarify the influences of a newly developed PSO (D-C Tron $Plus^{(R)}$) on citrus leaves, 0.33% or 1.0% of PSO were sprayed to potted 4-year-old citrus trees under some kinds of condition, and then the changes of photosynthesis, transpiration, stomatal conductance and chlorophyll fluorescence(Fv/Fm) were determined. When sprayed with 1.0% PSO, the photosynthetic rate, transpiration and stomatal conductance of citrus leaves were decreased by 20%, and then recovered in 20 days after treatment (DAT), while there were little influences by the spray of 0.33% PSO. The value of Fv/Fm decreased more under the $34/24^{\circ}C$ temperature condition than that of under the $30/20^{\circ}C$ and $28/16^{\circ}C$ condition. The high temperature ($50^{\circ}C$ for 10 hours)-treated trees sprayed with PSO 1.0% or PSO 1.0% plus dithianon 1/2000 dilution showed not only the increase of rate in dropped leaf but also the reduced photosynthesis and Fv/Fm compared with $30/20^{\circ}C$ temperature-treated ones. From the results of this study, the spray of 1.0% PSO can inhibit the physiological activities in citrus leaf, particularly under high temperature condition after spray or the mixing-spray with a fungicide (dithianon WP, 75%).

• Korean Journal of Food Science and Technology
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• v.26 no.2
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• pp.152-156
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• 1994

The purplish red pigment from the roots of Lithospermum erythrorhizon, a Korean edible wild plant, has been investigated concerning it's value as a natural colorant for Korean traditional foods. An attempt was made to isolate pigments and define their characteristics. Two compounds of isobutylshikonin and acetylshikonin were identified by melting point determination and spectra of UV, IR, and $^{1}H-NMR$. To examine the utility of these naphthoquinone pigments for foods, the effect of various pH values on stability were determined over a period of storage. Buffered solutions of acetylshikonin and isobutylshikonin at pH 3 and 5 showed stable purplish red. The absorption maxima if acetylshikonin and isobutylshikonin over the range of pH 3 to 7 were 518 nm and 520 nm, respectively. A bathochromic shift to 588 nm at pH 10 was observed on these two naphthoquinone pigments. Sensory evaluation was performed with acetylshikonin and isobutylshikonin of identical absorbance. These two pigments revealed purplish red color in Munsell system.

• The Korean Journal of Mycology
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• v.37 no.1
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• pp.117-119
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• 2009

Rhizopus soft rot caused by Rhizopus stolonifer occurred on strawberry (Fragaria ${\times}$ ananassa) in the plastic boxes in Jinju City Wholesale Market of Agricultural Products at Gyeongnam province in Korea on April 2008. The infected fruits were rapidly softened, water soaked and finally rotted. The symptoms were mainly occurred through wounds at harvest time. The colony color was white, cottony to brownish black after fully matured and numerous sporangiospores were formed on sporangia. The optimum growth temperature of the fungus was $30^{\circ}C$ on potato dextrose agar. Sporangia were globose or hemispheric shape of white color at initial stage and gradually changed with black color of $82{\sim}195{\mu}m$ in size. Sporangiophores were $12{\sim}25{\mu}m$ in width. Columella were hemispheric in shape, and $70{\sim}92{\mu}m$ in size. Sporangiospores were irregular round or oval in shape, brownish-black in color and $9{\sim}21\;{\times}\;7{\sim}8{\mu}m$ in size. This fungus formed stolones and rhizoid on PDA. On the basis of symptom, mycological characteristics and pathogenicity of the fungus, the causal fungus was identified as Rhizopus stolonifer (Ehrenb.) Vuill.

• The Journal of the Petrological Society of Korea
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• v.22 no.1
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• pp.1-8
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• 2013

Physical properties, XRF, UV-Vis, FTIR studies were carried out in order to characterize gemological features of ruby from Tajikistan. Fluorescence reaction of the Tajikistan ruby to short wave ultraviolet was moderate to very strong in red and long wave ultraviolet rays was weakly detected. UV-visible analysis strong absorption bands at 468.5, 475, 476.5 nm and broaden bands at 550 nm were observed for ruby due to $Cr^{3+}$. According to FT-IR analysis, all rubies from Tajikistan showed the similar patterns and kaolinite peaks at 3500, 3617, 3630, $3677cm^{-1}$ and boehmite broaden absorption bands at 3085 and $3320cm^{-1}$. Inclusions in Tajikistan ruby are observed solid inclusions, negative crystals, needle and silk inclusions. These distinctive characteristics mentioned above can be used to identify the locality and source of ruby stones from Tajikistan.

• Journal of the Korean Magnetics Society
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• v.10 no.5
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• pp.210-219
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• 2000

The magnetoresistance characteristics of FeN/Co/Cu/Co and FeN/Co/Cu/Co/Cu/Co/FeN multilayers using ferromagnetic iron-nitrides (FeN) has been studied. The microstructure of FeN film is the mixed ${\alpha}$-Fe and $\varepsilon$-Fe$_3$N phase on the condition that the flow rate of N$_2$ gas is over 0.4 sccm. The magnetoresistance effect is observed because of shape magnetic anisotropy induced by needle-shaped $\varepsilon$-Fe$_3$N phase. This magnetoresistance effect changes, because the degree that the shape magnetic anisotropy adheres to the adjacent Co pinned layer is varied according to the flow rate of N$_2$ gas and the thickness of FeN film. The best magnetoresistance effect is obtained on the condition that the thickness of Co free layer is 70 ${\AA}$ and the maximum MR ratio(%) value of 3.2% shows in the FeN(250 ${\AA}$)/Co(70 ${\AA}$)/Cu(25 ${\AA}$)/Co(70 ${\AA}$)/Cu(25 ${\AA}$)/Co(70 ${\AA}$)/FeN(250 ${\AA}$) mutilayer film which is fabricated at the N, gas flow rate of 0.5 sccm and the FeN film thickness of 250 ${\AA}$. Four steps are observed in the magnetoresistance curve owing to this difference of coercive force, because respective magnetic layers in the multilayer possess different coercive forces. These effects observed in these mutilayer films can be expected to application to the memory device the same MRAM as can carry out simultaneously four signals.

• Weed & Turfgrass Science
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• v.5 no.2
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• pp.101-104
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• 2016

Curvularia leaf blight of creeping bentgrass (Agrostis stolonifera) putting green by caused Curvularia trifolii was observed in Hapcheon, Korea. In July to September 2014, curvularia leaf blight developed on leaf blades of creeping bentgrass as small water-soaked lesions that subsequently turned into dark-colored, necrotic spots. The spots were expanded and became gray, grayish-brown, or light brown, circular to oblong lesions with purple to dark brown borders that often were surrounded by a yellow halo. The necrotic lesions coalesced, became irregular in shape and caused tip or complete blighting of the leaves. Blighted leaf blades appeared grayish-white to tan. The fungus was identified by morphological characters and 16S rDNA sequencing as C. trifolii. Conidia of the pathogen were short, with predominantly 3-septa, straight or often curved, with end cells frequently paler than intermediate cells. Size of the 3-septate conidia in culture are $26{\sim}28{\times}11{\sim}12{\mu}m$. Pathogenicity of the fungus was proved by artificial inoculation on the host. This is the first report of C. trifolii causing leaf blight on creeping bentgrass in Korea.

• Journal of Life Science
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• v.14 no.4
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• pp.689-695
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• 2004

This study was investigate the occurrence of bottom rot caused by Rhizoctonia solani at the crisphead lettuce fields in Uiryeong-gun, Gyeongsangnam-do from November to December in 2003. Incidence of bottom rot on crisphead lettuce was up to 5.3% at the six plastic houses. A total of 30 isolates of R. solani were obtained from diseased leaves of plants and were tested by artificial inoculation to the host. Among them, PY-1 isolate was selected showing highly virulent on the whole plant and was identified as R. solani AG1 (IB) based on the anastomosis test, morphological and cultural characteristics. Symptoms of bottom rot by PY-1 isolate produced small dark brown, depressed and elliptical spots on the lower part of leaves in the early stage as same as at the fields, were enlarged onto the upper part of leaves later, and the infected plant wilted and ultimately died in the end. For the pathogenicity test, triturated mycelia-inoculum (A$_{550}$=1.0) of PY-1 isolate was selected the most effective inoculum showing disease incidence of 51.1% for the mycelial inoculation at pot assay. Otherwise, WSRP media-inoculum (wheat brane ： sawdust ： rice brane ： PDB media=30 g ： 10 g ： 10 g ： 100 ml, w/w/w/v) of PY-1 isolate was effectual inoculum showing disease incidence of 61.6% for soil inoculation at the plastic house. Also, in selection of density and amount of inoculum, most suitable density of triturated mycelia-inoculum and amount of WSRP media- inoculum were determined as $A_{550}$=1.0 and 40 ml, respectively. This is the first report on the pathogenicity test using by WSRP media-inoculum of R. solani PY-1 isolate for the bottom rot of crisphead lettuce.

• Land and Housing Review
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• v.4 no.1
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• pp.107-117
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• 2013

This study aimed to assess the rental housing ABS in Korea, and to suggest ways of improving the structure of existing rental housing ABS. Thus, the three major assessment for existing public rental housing ABS case can be summarized as follows : First, when viewed in terms of the accounting treatment, rental housing ABS which use the future receivables as underlying asset, can not enjoy off-balance-sheet effect. Second, when viewed from the point of financing costs, the rental housing ABS interest rate being higher than unsecure bond is very unreasonable nevertheless the ABS being off-balanced. Third, when viewed from the liquidity effect, the originator (LH) use the ABS as a means of diversifying funding in a serious liquidity crisis situation. The Improvement of rental housing ABS based on the evaluation results can be summarized into two broad. First, it is a plan to handle the off-balance-sheet effect in a way of changing the accounting treatment of rental payment. Second, it is a plan to reducing the structuring cost and interest rate in ways of multi-asset securitization structure, self-trust structure, and adopting legal CB structure.

• Journal of the Mineralogical Society of Korea
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• v.1 no.2
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• pp.83-93
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• 1988

Amethysts in Eonyang Granite of Woolju-Kun, Kyungnam Province are frequently parallelly grown on top of preexisting smoky quartz crystallized on milky and colorless quartz crystals, which, as a whole, resemble "mushroom" in outer appearance. Fluid inclusions in the amethysts may be grouped into (1) gaseous inclusions (G>L), (2) liquid inclusions (L>G), (3) $L_{CO_2}$-bearing inclusions (L+G+$L_{CO_2}$), (4) halite-bearing inclusions (L+G+halite), (5) multiphase inclusions (L+G+halite+sylvite${\pm}$opaque mineral). In addition, euhedral K-feldspars and acicular hematite crystals are included in colorless-milky quartz and deep purple-red quartz, respectively. Filling temperatures of each type of fluid inclusions were measured as follows: $320{\sim}560^{\circ}C$ for gaseous inclusions; $100{\sim}290^{\circ}C$ for liquid inclusions; $200{\sim}310^{\circ}C$ for $L_{CO_2}$-bearing inclusions; $300{\sim}430^{\circ}C$ for halite-bearing inclusions; and $370{\sim}430^{\circ}C$ for polyphase inclusions. The finished-gem amethysts from Eonyang may be distinguished from Brazilian amethysts by the difference in filling degree of gaseous inclusions by the presence of hematite aciculae, and of $L_{CO_2}$-bearing inclusions, and also by the absence of Zebra-striation structure. They may also be differentiated from synthetic amethysts by presence of straight color banding, solid inclusions, and $L_{CO_2}$-bearing inclusions which are not found in synthetic materials.

• Journal of the Korean Crystal Growth and Crystal Technology
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• v.28 no.3
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• pp.99-105
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• 2018

In order to avoid un-uniform crystallization on the surface of a quartz glass crucible that is known to affect the production yield of the single crystal silicon, Ba (barium) was selected as a crystallization promotor and the inner surface of the crucible was coated using Ba (barium hydroxide octahydrate)-solution by the spray pyrolysis method. For un-coated crucible, it was found that the crystallization of its surface started at $1350^{\circ}C$, and at $1450^{\circ}C$ the surface was uniformly crystallized with ${\beta}$-cristobalite phase. It was found that the crucible coated with Ba began to be crystallized from $1000^{\circ}C$ and was uniformly crystallized on the crucible surface at $1300^{\circ}C$. In this case, ${\alpha}$-cristobalite and needle-shaped $BaSi_2O_5$ phase were created and disappeared as a crystal phase, and the ${\beta}$-cristobalite phase was eventually evenly distributed over the Ba-coated crucible surface.