• Journal of Environmental Health Sciences
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• v.18 no.1
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• pp.34-38
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• 1992

This study was carried out to investigate silicate-silicious in spring water and ground water. Samples were collected from 23 Stations of spring water and 2 Stations of ground water from August 1985 to July 1990 in Pusan area. Range and mean value of silicate-silicious of spring water and ground water were lower 2.12~22.70mg/l, 8.78mg/l, 13.90~19.05mg/l, 16.23mg/l than the criterion for drinking water as 50rng/l. The concentration of silicate-silicious had a great influence on precipitation, therefore it in summer was higher than in winter. The estimated regression line between chloride ion(x) and silicate-silicious(y) of the sampled water was y=19.366-0.604x(r=-0.7111).

• Proceedings of the Korean Geotechical Society Conference
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• 2009.09a
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• pp.529-534
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• 2009

This study had propose that a characteristic of recently developed Silicasol to make a close in this study, grouting material usually used portland cement and a characteristic is compared between Silicasol and sodium silicate in this study, examined strength and environmentally friendly for compare characteristics of sodium silicate and Silicasol through unconfined compressive strength, SEM analysis, Permeability test, Chemical Resistance test, leaching test etc. In the test, I gained that unconfined compressive strength of Silicasol three times promoted than sodium silicate Within 72 hours and I gined through analysis of SEM that Silicasol is more compactivetive than sodium silicate. In the result of test, it was found to be a environmentally friendly material as the toatal amount of eluviated elementary had small quantity.

• Transactions on Electrical and Electronic Materials
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• v.12 no.4
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• pp.135-139
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• 2011

In an effort to develop new electrical insulation materials, four different kinds of organically modified layered silicate were incorporated into an epoxy matrix to prepare nanocomposites for electrical insulation. Five wt% of organically modified layered silicates were processed in a planetary centrifugal mixer in an epoxy matrix, and the thermal, mechanical, and electrical properties of the cured epoxy/layered silicate were investigated. The morphology of the nanoscale silicate dispersed in the epoxy matrix was observed using transmission electron microscopy, and the interlayer distance was measured by wide-angle X-ray scattering diffraction analysis.

• Corrosion Science and Technology
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• v.15 no.1
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• pp.1-5
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• 2016

Zinc ethyl silicate coatings containing multi walled carbon nanotubes (MWCNTs) were prepared, to which we added spherical and flake shaped zinc particles. The anti-corrosive effects of MWCNTs and zinc shapes on the zinc ethyl silicate coated carbon steel was examined, using electrochemical impedance spectroscopy and corrosion potential measurement. The results of EIS and corrosion potential measurement showed that the zinc ethyl silicate coated with flake shaped zinc particles and MWCNT showed lesser protection to corrosion. These outcomes were in agreement with previous results of corrosion potential and corrosion occurrence.

• Journal of Applied Reliability
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• v.12 no.4
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• pp.275-285
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• 2012

This paper presents a changes of luminescence property for converted white LEDs with the commercially available silicate phosphor. If silicate phosphor's quantity increase step by step. luminescence property will be changing. we analyze luminescence property for these change and carry out the high temperature aging test for 7,000 hours, the high temperature and humidity aging test for 7,000 hours for reliability. LED degradation not only results in reduced light output but also in color changes. so we monitor correlated color temperature (CCT), chromaticity coordinates(x, y) and spectrum intensity. Those results suggest that humidity factor more bad effect in color changes than temperature factor and Lighting quality is related with quantity of phosphor.

• Transactions on Electrical and Electronic Materials
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• v.13 no.3
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• pp.153-156
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• 2012

In order to develop electrical insulation materials, epoxy/micro-silica composite (EMC) and epoxy/micro-silica/nano-silicate composite (EMNC) were prepared, and their tensile and flexural strength, AC insulation breakdown strength and thermal conductivity and thermal expansion coefficient were compared. Nano-silicate was prepared in an epoxy matrix by our AC electric field process. All properties of the neat epoxy were improved by the addition of micro-silica, which was improved much further by the addition of nano-silicate to the EMC system.

• Bulletin of the Korean Chemical Society
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• v.17 no.8
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• pp.696-699
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• 1996

Silicate and borosilicate gels were prepared by the sol-gel process and thermally treated in the 150-850 ℃ temperature range. Solid-state 1H MAS and 29Si CP/MAS NMR spectroscopy were used to investigate the effects of heat treatments on the silicate gel to glass conversion process. The 1H NMR isotropic chemical shifts and the relative intensities of hydrogen bonded and isolated silanol groups have been used to access the information concerning the dehydration process on the silicate gel surface. The 29Si NMR isotropic chemical shifts affected by the local silicon environment have been used to determine the degree of crosslinking, i.e. the number of siloxane bonds. These NMR results suggest that the silicate gel to glass conversion process is occurred by two stages which are dependent on the temperature; (1) the formation of particles up to 450 ℃ and (2) the formation of large particles by aggregation of each separated single particle above 450 ℃. In addition, the effects of B atom on the formation of borosiloxane bonds in borosilicates have been discussed.

• Nuclear Engineering and Technology
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• v.55 no.7
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• pp.2366-2372
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• 2023

Are borate and silicate glasses suitable for working as shieling materials against fast neutrons? To correctly answer the above question, some silicate, and borate-based glasses were fabricated and irradiated with various doses of fast neutrons varied between 1.73 and 12.10 MGy. The color and hardness of the fabricated glasses were affected by the fast neutron fluence where the transparent glasses turned colored as well as the hardness of the fabricated glasses was decreased. The gamma-ray spectrometric analysis shows a high activity concentration produced in the barium borate glasses due to the formation of radioisotopes Ba-131 and Ba-133 reaches to 5.92E+05 Bq and 4.25E+03 Bq, respectively for sample Cd-5 Batch 3. Additionally, the gamma-ray spectrometric analysis for the sodium silicate glasses shows low activity concentrations emitted from isotopes formed due to the activation of Y₂O₃-associated impurities. These activities are low compared to that emitted by barium borate-based glasses.

• 한국신재생에너지학회:학술대회논문집
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• 2010.11a
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• pp.89.2-89.2
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• 2010

고체산화물 연료전지는 $800{\sim}1000^{\circ}C$인 고온에서 작동하므로 적용되는 밀봉재의 요구조건은 매우 중요하다. 본 연구에서는 SOFC 밀봉재로서 $SiO_2-B_2O_3-RO$계 결정화 유리를 선정하였으며 작동온도 부근에서 결정화를 유도하여 고온점성유동을 제어하고자 하였다. 따라서 $SiO_2-B_2O_3-RO$계에 RO인 CaO, SrO, BaO, MgO를 상호 치환하였을 때 결정상의 생성, 생성온도, 생성결정의 종류가 sealing 특성에 어떠한 영향을 주는가를 검토하였다. 결정화유리를 $800^{\circ}C$로 유지하였을 때 생성되는 주 결정상은 Calsium silicate, Strontium silicate, Barium silicate, Magnesium silicate이였으며 Strontium silicate 의 생성속도가 가장 빨랐으며 결정상은 불산으로 에칭하여 SEM으로 관찰하였다. Barium silicate를 유도한 결정화 유리가 $800^{\circ}C$에서 1000시간 유지하였을 경우 가장 내화학성이 우수하며 강도값도 154MPa로 가장 높았다. 또한 부분 결정화를 통해 $800^{\circ}C$ 점성유동이 제어됨을 고온현미경을 통해 관찰하였다.

• The Plant Pathology Journal
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• v.20 no.4
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• pp.277-282
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• 2004

Amendments of a recirculating nutrient solution with potassium silicate were evaluated as a means to control Phytophthora capsici infections on pepper plant(Capsicum annuum L.). Supplying the solutions with 100 or 200 ppm of silicate significantly reduced motility, root decay, and yield losses attributed to infection of P. capsici. Treating inoculated plants with potassium silicate increased root dry weights and number of fruit, especially high-grade fruit. Results were slightly superior to non-inoculated controls. The two varieties, PBC 137 and PBC 602, responded similarly to the treatments. No significant differences were observed between the 100- and 200 ppm silicate treatments. Results were better when greenhouse conditions favored the spread of P. capsici. Silicon alone did not increase pepper yield, suggesting that it acts as a disease suppression agent rather than as a fertilizer, The phenomena by which silicon confers protection against P. capsici infection and disease development are not fully understood, but our results indicate that mechanisms other than a mechanical barrier to fungal penetration are involved.