• FLOWER RESEARCH JOURNAL
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• v.18 no.1
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• pp.50-56
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• 2010

This experiment was carried out to examine the effect of a silicate fertilizer on the growth and development of potted plants. Cutting of Kalanchoe blossfeldiana 'Kaluna' and 'Taos', and Dianthus caryophyllus L. 'Kazan' and 'Tula' were grown in 50 and 128-cell plug trays, respectively. Rooted cuttings transplanted to the mixture of a commercial medium and perlite (5:1, v/v) supplemented with a silicate fertilizer at 0, 40, 80, 120 or $160g{\cdot}L^{-1}$ medium was evaluated. A silicate fertilizer supplementation at $40g{\cdot}L^{-1}$ medium resulted in the greatest plant height, leaf thickness, and root fresh and dry weights in both kalanchoe and carnation. However, plant height was suppressed in the treatment of a silicate fertilizer supplementation at higher concentrations in both kalanchoe and carnation. According to the scanning electron microscope images of transversal sections of tissues of roots and leaves in kalanchoe and carnation, the treatment of a silicate fertilizer supplementation at $40g{\cdot}L^{-1}$ medium resulted in plants with more compact tissue than the control.

• The Journal of the Petrological Society of Korea
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• v.1 no.1
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• pp.1-24
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• 1992

Precambrian metamorphic rocks of the Gapyeong-Cheongpyeong area consist of banded gneiss, augen gneiss, leucocratic gneiss, quartz schist and quartzite, together with minor intercalations of serpentinite, amphibolite and marble. Mineral assemblages of meta-sedimentary rocks are classified into three types: sillimanite-free; sillimanite-bearing; and sillimanite+K-feldspar-bearing assemblages. Compositions of metamorphic phases depend on the type of mineral assemblages. In particular, the Ca contents of plagioclase and garnet are high in sillimanite-free assemblges. Kyanite occurs in three samples, and coexists with sillimanite in one sample. The presence of kyanite indicates that metamorphic rocks of the study area have experienced the Barrovian type metamorphism. Peak metamorphic conditions estimated from various geothermobarometers and phase equilibria are 618-674$^{\circ}C$ and 6.5${\pm}$2.0 kbar for sillimanite-free assemblages, and 701-740$^{\circ}C$ and 4.4${\pm}$0.8 kbar for sillimanite-bearing assemblages, respectively. Furthermore, a clockwise P-T-time path is deduced for the study area, based on the following observations: (1) the polymorphic transition of kyanite to sillimanite, (2) the occurrence of sillimanite and K-feldspar belonging to the upper amphibolite facies, and finally (3) the retrograde metamorphism characterized by muscovite-, chlorite-, and actinolite-bearing assemblages.

• Korean Journal of Soil Science and Fertilizer
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• v.39 no.6
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• pp.334-338
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• 2006

This study was conducted to evaluate the effect of improvement of soil physical properties such as deep plowing, subsoil breaking and diagnostic fertilization on the yield of rice and nitrogen-use efficiency in direct seeding on flooded paddy surface of rice. The effects of deep plowing, subsoil breaking and diagnostic application of N, P, K fertilizers, Latex coated urea(LCU), compost, silicate were investigated. The soil physical properties, such as bulk density, hardness and porosity were improved and the content of organic matter and available $SiO_2$ were also increased by deep plowing and subsoil breaking. The amount of $NH_4-N$ in soil was highly increased by diagnostic fertilization and deep plowing at 5th leaf stage. The nitrogen-use efficiency was the highest at the diagnostic application of LCU 70% applied as basal dressing with subsoil breaking. The yield of rice increased by 8% under the diagnostic application of LCU 70% applied as basal dressing with subsoil breaking compared with the conventional application.

• Korean Journal of Soil Science and Fertilizer
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• v.50 no.6
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• pp.634-643
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• 2017

No-tillage is an effective practice to save labor input and reduce methane emission from the paddy. Effects of tillage and cultivation methods on carbon accumulation and soil properties were investigated in the treatments of tillage-transplanting (T-T), tillage-wet hill seeding (T-WS), minimum tillage-dry seeding (MT-S) and no-tillage dry seeding (NT-S) of rice. Soil carbon was higher in NT-S and MT-S, compared to T-T and T-WS. In NT-S and MT-S, soil carbon contents were the highest in the top soil (5 cm depth) and decreased with soil depth. In T-T and T-WS, however soil carbon contents showed no significant difference up to soil depth of 15 cm from the top. Carbon content was the highest in the soil particle size under $106{\mu}m$ and decreased as the soil particle size increased. Contents of water-stable aggregates in NT-S and MT-S were higher than those of T-T and T-WS. In NT-S and MT-S, contents of water-stable aggregates were the highest in the top soil and significantly decreased with soil depth while no significant difference up to the soil depth of 15 cm in T-T and T-WS. Available $SiO_2$ contents in the top soil were the highest in NT-S and MT-S while the lowest in T-T and T-WS. It is concluded that minimum or no disturbance of soil in rice cultivation can increase carbon accumulation in the soil, especially in the top layer, and subsequently contribute to the formation of the water-stable soil aggregates.

• Korean journal of applied entomology
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• v.60 no.4
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• pp.431-448
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• 2021

We decided the efficient application timings of organo-synthetic insecticides for controlling the first generation larvae of O. furnacalis through investigations of insect stage-specific densities, damage aspects in maize, and effects of insecticides. A waxy maize cultivar, Ilmichal, was cultivated from April 20 (sowing) to July 26 (harvest, dough stage of maize) in Suwon, 2016. The maximum and 50% cumulative catch dates of the overwintering generation adults in the sex pheromone trapping were May 29 and May 31, respectively. Most of the first generation larvae finished their occurrence till the early reproductive stage of maize. The first generation larvae fed on leaves inside the whorl leaves before tassel and stem development of maize, sequentially moved to tassel and stem, and then moved finally to stem and ear parts. In the results of insecticide applications at different dates, the 9-11 leaf stage (June 10~17) and the 6-7 leaf stage (June 3) of maize were the most efficient application timings for direct spray of Etofenprox EC to maize, and for application of Carbofuran granules onto soil surface, respectively, which resulted in suppression of tunnelling damages. The timings for the two insecticides were 12-19 days and 5 days after the adult maximum catch date, respectively. Those timings after the 50% cumulative adult catch date were advanced 2 days.

• Journal of the Korean earth science society
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• v.39 no.6
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• pp.575-592
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• 2018

This study investigates the formation mechanism of columnar joints at the Sanin Kaigan Geopark in Japan based on its morphology, rock type and igneous structure. Columnar joints distribute to five areas of three prefectures. That is, Kyogasaki, Byobuiwa, Tateiwa and Kyugenkado in Kyotango area of Kyoto prefecture; Genbudo and Kinumaki Shrine in Toyooka City of Hyogo prefecture; Yoroinosode, Takanosushima, Mini-Yoroinosode in Kamicho Town of Hyogo prefecture; Miooshima and Nagasakihana, Shitaara Domon, Kuzakuishi, Moroyose dyke in Shinonsencho Town of Hyogo prefecture; Shirawara dyke in Iwamicho Town in Tottori prefecture. Igneous structures are divided into three types: lava flow, sill and dyke. Lithologies are divided into five types including basalt, andesite, dacite, rhyolite, and quartz porphyry. Lava flow shows colonnade and entablature. However, entablature is not seen in the sills and dykes in the area. Although the polygons of columnar joint vary from tetragon to octagon, hexagon is most frequently found. The width of colonnades ranges from 10cm to 1m, but their size does not correlate with its $SiO_2$ contents. Meanwhile, their size and morphology at single site are comparatively uniform.

• Journal of Korean Neurosurgical Society
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• v.62 no.6
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• pp.649-660
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• 2019

Objective : To analyze the angiographic features and clinical course, including treatment outcomes and the natural course, of fusiform middle cerebral artery aneurysms (FMCAAs) according to their location, size, and configuration. Methods : We reviewed the literature on adult cases of FMCAAs published from 1980 to 2018; from 25 papers, 112 FMCAA cases, for which the location, size, and configuration could be identified, were included in this study. Additionally, 33 FMCAA cases in our hospital were included, from which 16 were assigned to the observation group. Thus, a total of 145 adult FMCAA cases were included. We classified the FMCAAs according to their location (l-type 1, beginning from prebifurcation; l-type 2, beginning from bifurcation; l-type 3, beginning from postbifurcation), size (small, <10 mm; large, ${\geq}10mm$; giant, ${\geq}25mm$), and configuration (c-type 1, classic dissecting aneurysm; c-type 2, segmental ectasia; c-type 3, dolichoectatic dissecting aneurysm). Results : The c-type 3 was more commonly diagnosed with ischemic symptoms (31.8%) than hemorrhage (13.6%), while 40.9% were found accidentally. In contrast, c-type 2 was more commonly diagnosed with hemorrhagic symptoms (14.9%) than ischemic symptoms (10.6%), and 72.3% were accidentally discovered. According to location, ischemic symptoms and hemorrhage were the most frequent symptoms in l-type 1 (28.6%) and l-type 3 (34.6%), respectively. Most of l-type 2 FMCAAs were found incidentally (68.4%). Based on the size of FMCAAs, only 11.1% of small aneurysms were found to be hemorrhagic, while 18.9% and 26.0% of large and giant aneurysms were hemorrhagic, respectively. Although four aneurysms of the 16 FMCAAs in the observation group increased in size and one aneurysm decreased in size during the observation period, no rupture was seen in any case and there were no significant predictors of aneurysm enlargement. Of 104 FMCAAs treated, 14 cases (13.5%) were aggravated than before surgery and all the aggravated cases were l-type 1. Conclusion : While ischemic symptoms occurred more frequently in l-type 1 and c-type 3, hemorrhagic rather than ischemic symptoms occurred more frequently in l-type 3 and c-type 2. In case of l-type 1 FMCAAs, more caution is required in determining the treatment due to the relatively high complication rate.

• Journal of the Microelectronics and Packaging Society
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• v.25 no.4
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• pp.143-148
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• 2018

Sodium silicate based silica aerogels are lower in cost than silica alkoxide based silica aerogels, but the demand is decreasing as their physical properties are lowered. In this research, acetonitrile as a drying control chemical additive (DCCA) is added in the sol state to improve the pore-structural properties of sodium silicate based silica aerogel by preventing the agglomeration of particles and cross-linked bond. The sodium silicate based silica aerogel by ambient pressure drying were prepared by sol-gel process. Acetonitrile/$Na_2SiO_3$ molar ratio of 0, 0.05, 0.1, 0.15, and 0.2 was added to the sol state. The physical properties of the final product were analyzed using Fourier transform infrared, contact angle measurement, Brunauer-Emmett-Teller and Barrett-Joyner-Halenda measurements and field emission scanning electron microscopy. It was confirmed that the sample with adding 0.15 molar ratio of acetonitrile and sodium silicate showed a high specific surface area ($577m^2/g$), a high pore volume (3.29 cc/g), and a high porosity (93%) comparable to the pore-structural properties of silica alkoxide based silica aerogels.

• Applied Chemistry for Engineering
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• v.22 no.1
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• pp.104-108
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• 2011

In the non-conductive adhesives (NCAs) for adhesion of micro electro mechanical system (MEMS), there are some problems such as delamination and cracking resulting from the large differences of coefficients of thermal expansion (CTE) between NCAs and substrates. So, the addition of inorganic particles such as silica and nano clay to the CTEs composit have been applied to reduce the CTEs of the adhesives. Additions of the flexibilizers such as siloxanes have also been performed to improve the flexibility of epoxy composite. Amino modified siloxane (AMSs) were used to improve compatibility between epoxy and siloxane. In this study, glass transition temperatures (Tg) and moduli of those composites were measured to confirm the effects of AMS with two different equivalents on thermal/mechanical properties of AMS/epoxy composites. Tg of KF-8010/epoxy composites decreased from 148 to $122^{\circ}C$ and those of X-22-161A/epoxy composites decreased from 148 to $121^{\circ}C$. Moduli of KF-8010/epoxy composites decreased from 2648 to 2143 MPa by adding KF-8010 and moduli of X-22-161A/epoxy composites decreased from 2648 to 2014 MPa. In short, using long Si-O chain AMS leads to a greater decrease in moduli. However, haven't showed significant differences in Tg's.

• Journal of the Microelectronics and Packaging Society
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• v.27 no.4
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• pp.135-141
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• 2020

The silica aerogels with benzene-bridged were designed to have uniform network structure, ordered pore structure, improved mechanical properties and excellent textural properties. Adding organic to enhance the mechanical properties of silica aerogels is a common method, but textural properties of aerogels with organic are reduced due to the organic-inorganic phase separation. In this paper, we use a simple and low-cost method to increase mechanical properties while maintaining textural properties of SiO2 aerogels. Two types of benzene-bridged precursors were prepared to study the effect of the number of hydroxyl band on the textural and mechanical properties. The porous silica aerogel was prepared by a simple, cost effective and pollution-free sol-gel method. This method does not require additional silylating reagents. The benzene-bridged silica aerogel samples prepared had excellent textural properties, high specific surface area (1,326 ㎡/g), porous structure and hydrophobicity (>140°). The mechanical strength of 2T4 is more than 5 times that of pure silica aerogel.