• Korean Chemical Engineering Research
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• v.52 no.2
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• pp.166-174
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• 2014

This research investigated the aging properties of the $B-KNO_3$ system as the igniter. The $B-KNO_3$ system showed the degradation in ignition properties depending on the method and period of storage. It should be found out the cause of the degradation to predict the reliability of the igniters. The changes of the properties by the degradation after aging tests were analyzed by microstructure analysis, XRD analysis and thermal analysis using DSC. It was found out that the lattice parameters of the $KNO_3$ as the oxidizer in the ignition system was changed into the JCPDS values as the aging time increased. Conclusively, the changes of the crystal structure of oxidizer affected the activation energy increasing as aging time increased.

• Korean Journal of Plant Resources
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• v.29 no.2
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• pp.235-240
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• 2016

Factors affecting germination of seeds in the forms of various environment and chemical compounds. The present study was aim to produced effective seed propagation method of Astilbe koreana (Kom.) Nakai which had expected high value for the cut flower, ornamental and pharmaceutical material. Seed width and length ranged 0.62, 2.22 ㎜, respectively, and weight of thousand seeds was 40.5 ㎎. As result of imbibition test, showed moisture content of fresh seed (2.57%) increased rapidly by water-soaking treatment under 24 hours, recording to maximum value of 29.8%, and expansion of the seed coat was observed. Seed germination was the best at 15℃ and light conditions (40.8%) among temperature and light conditions treated. Percent germination of seeds was improved under the low (15, 20℃) than high temperature (25, 30℃). In addition, the seed was not germinated at dark condition regardless of temperature. Seeds of A. koreana thus seemed that it had low temperature germinability conditions. To improve germination rate, seeds were submerged in various concentrations of growth regulators such as GA₃ and kinetin, and minerals as KNO₃ and KCl. As a results, KNO₃ treatment, regardless of concentrations, promoted germination compared to control. Especially, percent of germination (77.8%), germination energy (96.1%), mean germination time (11.3 days) and T₅₀ (6.5 days) were effectively improved by treatment of KNO₃ 20 mM.

• Horticultural Science & Technology
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• v.16 no.2
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• pp.219-221
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• 1998

This study was carried out to investigate seed bulbs production of 'Namdo' garlic (Allium sativum L.) by treating with 200 mM $K_3PO_4$ and 200 mM $KNO_3$ solution to bulbils. The growth characteristics of garlic plants derived from bulbils sown on 3 different dates were compared to those of plants derived from non-treated bulbils. Time required for 50% shoot emergence ($T_{50}$) was shortened as the sowing dates delayed. However, the final emergence rate was increased in the early sowing dates, and was high when treated with $K_3PO_4$ and sown on Oct. 10. The % clove differentiation of bulb was not significantly affected by sowing date and chemicals treatment of the bulbils. In all treatments, % clove differentiation was greater than 85%. The average bulb weight was increased with earlier sowing. Bulbils treated with $K_3PO_4$ and sown on Oct. 10 exhibited the best growth and yield. which was 27% higher compared to the non-treated bulbils.

• Korean Journal of Plant Resources
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• v.36 no.4
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• pp.381-389
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• 2023

The germination characteristics of Pseudolysimachion kiusianum var. diamantiacum (Nakai) T.Yamaz., a rare and endemic plant designated by the Korea Forest Service, were investigated according to light conditions, temperature, and pretreatment. As a result of the germination experiment according to light conditions, it was determined that P. kiusianum is a photoblastic seed that does not germinate at all in dark conditions. The optimum germination temperature of the seeds was found to be 20-25℃, considering the final germination rate and germination time. Three growth regulators (IAA, GA₃, kinetin) and two inorganic salts (KNO₃, KCl) were pretreated to improve the germination rate of P. kiusianum seeds. The growth regulators IAA and kinetin had no significant effect on improving the germination rate of P. kiusianum seeds. On the other hand, GA₃ significantly increased the final germination percentage and germination rate regardless of the concentration, especially the treatment of more than 500 mg·L^-1 at 20℃ was more than 4 times more effective than the untreated. The inorganic salts KNO₃ and KCl had no significant effect on the seeds of P. kiusianum at low concentrations, but at higher concentrations (40 mM and 300 mM, respectively), they improved the germination rate and germination age by 2 times compared to the untreated. The results of this study will be useful for the mass propagation of P. kiusianum, which has the potential to be utilized as a native plant for restoration.

• Conservation Science in Museum
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• v.13
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• pp.45-49
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• 2012

A scientific analysis was carried out on the 14 pieces of glass beads excavated from the Daho-ri site NO. 6, Changweon. Most of the glass pieces were made of light blue transparent glass with round bubbles aligned in a regular direction. As a result of the SEM-EDS analysis, all the glass pieces turned out to be within the potash glass group (K₂O-SiO₂) and were identified to be the LCA (Low CaO, Low Al₂O₃) series glass, of which the concentration is 5% or below for CaO and Al₂O₃ respectively. In addition, it is presumed that plant materials were refined or a mineral (saltpetre, KNO₃) was used as the raw materials for making potash and also that the ingredient acting as a colorants for light blue color was affected deeply by CuO.

• Journal of Sensor Science and Technology
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• v.22 no.4
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• pp.244-248
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• 2013

The discovery of a two-dimensional electron gas (2DEG) in $LaAlO_3$ (LAO)/$SrTiO_3$ (STO) heterostructure has stimulated intense research activity. We suggest a new structure model based on $KNbO_3$ (KNO) material. The KNO thin films were grown on $TiO_2$-terminated STO substrates as a p-type structure ($NbO_2/KO/TiO_2$) to form a two-dimensional hole gas (2DHG). The STO thin films were grown on KNO/$TiO_2$-terminated STO substrates as an n-type structure to form a 2DEG. Oxygen pressure during the deposition of the KNO and STO thin films was changed so as to determine the effect of oxygen vacancies on 2DEGs. Our results showed conducting behavior in the n-type structure and insulating properties in the p-type structure. When both the KNO and STO thin films were deposited on a $TiO_2$-terminated STO substrate at a low oxygen pressure, the conductivity was found to be higher than that at higher oxygen pressures. Furthermore, the heterostructure formed at various oxygen pressures resulted in structures with different current values. An STO/KNO heterostructure was also grown on the STO substrate, without using the buffered oxide etchant (BOE) treatment, so as to confirm the effects of the polar catastrophe mechanism. An STO/KNO heterostructure grown on an STO substrate without BOE treatment did not exhibit conductivity. Therefore, we expect that the mechanics of 2DEGs in the STO/KNO heterostructures are governed by the oxygen vacancy mechanism and the polar catastrophe mechanism.

• FLOWER RESEARCH JOURNAL
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• v.16 no.3
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• pp.174-178
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• 2008

This study was carried out to investigate the effect $GA_3$, moist chilling storage and priming treatments on seed germination of Caltha palustris var. membranacea. Percent germination was greatly improved by $GA_3$ treatment. However, no significant differences were observed among concentrations and soaking periods of $GA_3$. Optimum $GA_3$ treatment was one hour presoaking in a 100mg${\cdot}L^{-1}$ solution. Germination enhancing effect of moist chilling stroage was significantly greater than that of $GA_3$. Chilling treatment for five weeks resulted in the greatest percent germination of 60.3%. Unlike the role of $GA_3$ and moist chilling storage, no appreciable effect on seed germination was observed by the priming the seeds with either a $Ca(NO_3)_2 $ or $KNO_3$ solution.

• Journal of the Korean Ceramic Society
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• v.52 no.2
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• pp.137-139
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• 2015

In this study, we examined the influence of molten $KNO_3$ flow on mechanical properties and their deviation when a chemical toughening process was applied to soda lime silicate glass ($Na_2O-CaO-SiO_2$). $KNO_3$ melt flow was controlled using three methods: (1) glass tray rotation, (2) impeller stirring, and (3) natural convection. DOL and hardness were found to be enhanced by tray rotation because this rotation was able to maintain the concentration around the glass surface, in contrast to other methods. However, there did not appear to be a statistically significant difference in the 3-point bending strength for the three flow conditions due to the ground edge condition.

• Korean Journal of Plant Resources
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• v.29 no.4
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• pp.385-392
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• 2016

This research was performed to develop seminal propagation method of Saururus chinensis (Lour.) Baill. by conducting a rigorous germination study. Well-selected seeds were dry-stored at 4 ± 1.0℃ during the experiment. To study dormancy type, non-stored seeds were analyzed by embryo observation, germination test and detecting for any difficulties in seed coat to absorb moisture. Then to improve germination, seeds were submerged for 24 hours in a solution of varying concentrations containing one of plant growth regulators and minerals. According to research, fleshly matured seeds had an undifferentiated embryo and had a low germination rate below 5%. In addition, water submersion led to moisture absorption, embryo in the seeds grew and germinated so it was deemed morphophysiological dormant seeds. Percent germination (PG) and germination energy (GE) was greatly improved by soaking in plant growth regulators and minerals for 24 hours. Especially, 500 ㎎/L GA₃ treatment resulted in the highest GE as 46.1%. KNO₃ meaningfully improved PG (54.3∼57.7%) at 10∼20 mM but effect of minerals on germination acceleration as GE were negatively impacted in all concentrations.

• Journal of the Korean Electrochemical Society
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• v.23 no.4
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• pp.97-104
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• 2020

One of the main challenges of electrochemical water splitting technology is to develop a high performance, low cost oxygen-evolving electrode capable of substituting a noble metal catalyst, Ir or Ru based catalyst. In this work, CoFe₂O₄ nanoparticles with sub-44 nmsize of a inverse spinel structure for oxygen evolution reaction (OER) were synthesized by the injection of KNO₃ and NaOH solution to a preheated CoSO₄ and Fe(NO₃)₃ solution. The synthesis time of CoFe₂O₄ nanoparticles was controlled to control particle and crystallite size. When the synthesis time was 6 h, CoFe₂O₄ nanoparticles had high conductivity and electrochemical surface area. The overpotential at current denstiy of 10 mA/㎠ and Tafel slope of CoFe₂O₄ (6h) were 395 mV and 52 mV/dec, respectively. In addition, the catalyst showed excellent durability for 18 hours at 10 mA/㎠.