• Journal of the Korean Wood Science and Technology
• /
• v.29 no.2
• /
• pp.126-132
• /
• 2001

This research is carried out to investigate the formation and preservative effectiveness of inorganic substance, calcium carbonate($CaCO_3$), in wood. The specimens were prepared by the impregnation with saturated solutions of potassium carbonate($K_2CO_3$) into the wood followed by precipitation in saturated solutions of calcium chloride($CaCl_2$) for 24h, 72h and 120h, and then they were leached in instrument flowing with water for 24h. The weight percent gains of $K_2CO_3$ solution impregnated specimens reached approximately a maximum value (108.1%) by 72h precipitation in $CaCl_2$ solutions. Inorganic substances were observed to he produced in the lumina of tracheids of specimens. From these inorganic substances filling in the tracheids, characteristic X-rays of calcium(Ca-$K_{\alpha}$) were detected by energy dispersive X-ray analyzer. Moreover, it was shown from a leaching treatment that these substances could not he leached easily from the specimens. Therefore, they were could he considered to be insoluble calcium carbonates. The weight losses of the prepared specimens were hardly occurred by test fungi attacks. Thus inorganic substances in specimens can be said to have preservative effectiveness.

• KEPCO Journal on Electric Power and Energy
• /
• v.5 no.4
• /
• pp.337-341
• /
• 2019

In this study, the effects of two materials, active alumina and CaO based inorganic binder, which cause the side reaction on the K₂CO₃-based solid CO₂ sorbents was investigated. K₂CO₃-based solid sorbents called KAM series was prepared by spray drying method and then measured its physical properties and CO₂ sorption capacity. Among the KAM series sorbents, KAM(0.5) maintained high CO₂ sorption capacity of 7.6 wt% after 3 cycle of sorption/regeneration reaction and showed very low attrition loss as low as 3.1 % which was measured by ASTM D5757-95.

• Journal of Biosystems Engineering
• /
• v.36 no.2
• /
• pp.96-108
• /
• 2011

Several methods of in-field measurements of Nitrogen and other soil properties using cores extracted by a hydraulic soil sampler were evaluated. A prototype core scanner was built to accommodate Veris Technologies commercial Vis-NIRS equipment. The testing result for pH, P and Mg were close to RPD (Ratio of Prediction to Deviation = Standard deviation/RMSE) of 2, however the scanner could not achieve the goal of RPD of 2 on some other properties, especially on nitrate nitrogen ($NO_3$) and potassium (K). In situ NIRS/EC probe showed similar results to the core scanner; pH, P and Mg were close to RPD of 2, while $NO_3$ and K were RPD of 1.5 and 1.2, respectively. Correlations between estimations using the probe and the core scanner were strong, with $r^2$ > 0.7 for P, Mg, Total N, Total C and CEC. Preliminary results for mid-IR spectroscopy showed an $r^2$ of 0.068 and an RMSE for nitrate (N) of 18 ppm, even after the removal of calcareous samples and possible N outlier. After removal of calcareous samples on a larger sample set, results improved considerably with an $r^2$ of 0.64 and RMSE of 6 ppm. However, this was only possible after carbonate samples were detected and eliminated, which would not be feasible under in-field measurements. Testing of $NO_3$ and K ion-selective electrodes (ISEs) revealed promising results, with acceptable errors measuring soil solutions containing nitrate and potassium levels that are typical of production agriculture fields.

• Applied Chemistry for Engineering
• /
• v.5 no.1
• /
• pp.160-175
• /
• 1994

Fibrous potassium hexatitanate whisker with the size of $ID=0.5{\sim}1{\mu}m$ and length=$100{\sim}1000{\mu}m$ (aspect ratio=100~1000) was produced through the reaction between titanium dioxide and potassium carbonate using the slow-cooling calcination followed by water leaching treatment. The optimum condition for the production of fibrous potassium titanate was calcination temperature of $1100^{\circ}C$ for 5hrs, $TiO_2$ mole ratlo to $K_2CO_3$ of 4.5 and slow-cooling rate of $0.5^{\circ}C/min$ to $860^{\circ}C$. Fibrous crystal are grown by the association between the solid potassium titanate and liquid phase during the slow-cooling process. The Proper water leaching condition for removing of K component was leaching time of 10hrs in boiling water. Pressurizing of the mixture of $K_2CO_3$ and $TiO_2$ to be calcinated became effective on the growth of fibrous crystal.

• Journal of the Korean Society of Combustion
• /
• v.22 no.2
• /
• pp.9-18
• /
• 2017

In this study, we measured that fire characteristics of four wood species using indoor finish materials. Wooden specimens were treated with fire retardant chemicals such as diammonium phosphate and potassium carbonate. The wooden specimens are Larix kaempferi, Pinus koraiensis, Cryptomeria japonica, and Chamaecyparis obtusa, which are used for indoor finish. The heat release rate (HRR) values of fire retardant treated woods were confirmed lower than that of untreated woods. For specific details, the HRR values of vacuum impregnated specimens for Pinus koraiensis and Cryptomeria japonica were measured lower than coatings. However, those of Larix kaempferi and Chamaecyparis obtusa showed the opposite effect to it. Total heat release rate values of all wooden specimens, vacuum impregnated were lower than coated specimens.

• Bulletin of the Korean Chemical Society
• /
• v.35 no.7
• /
• pp.1970-1972
• /
• 2014

A facile and efficient synthesis of dronedarone hydrochloride starting from commercially available 4-nitrophenol is described. This approach features a tandem-type synthesis of 3-carbonylated benzofuran involving cyclization of 2-ethynylphenol followed by $CO_2$ fixation at the 3-position of the benzofuran ring mediated by potassium carbonate without the addition of any transition metal catalyst.

• Proceedings of the Korea Air Pollution Research Association Conference
• /
• 2003.11a
• /
• pp.485-486
• /
• 2003

산업사회의 발전과 문화생활의 향상에 따라 에너지 사용은 계속 증가해 왔으며, 이에 따른 환경문제 또한 꾸준히 제기되고 있다 산업구조상 화석연료를 주 에너지원으로 사용하고 있는 우리나라의 경우 온실 가스중 $CO_2$가 87.7%를 차지한다. 또한 이 $CO_2$가 대기 중에서 10.0%가 초과되면 인체에 심각한 신진대사의 이상, 중앙신경계의 장애가 발생할 수 도 있다(환경부, 2000). 에너지 경제연구원은 "2010년까지 2000년 수준으로 $CO_2$ 배출량을 줄이면서 국내 총생산은 17.5% 감소할 전망"이라고 분석했다(에너지 관리공단, 2003). (중략)

• Textile Coloration and Finishing
• /
• v.14 no.5
• /
• pp.294-301
• /
• 2002

The effects of various parameters on partial decoloration of cotton dyeings using discharge reactive dye were investigated. The decoloration of dyed cotton fabrics with varying pH were very sensitive below 100g/1 of amount of potassium carbonate. Our results did indicate any significant changes in color when the amount of Rongalite C in reducing liquor was increased 10g/l to 200g/l. The steaming time had significant effects on fade-out, with an steaming time of 3~5 min. being sufficient for deceleration build up. The change of color below $130^\circ{C}$ was not significant and it only become evident above $140^\circ{C}$. The additional color changes did not cause by washing under suitable concentrations of oxidation and neutralization agents. The decoloration treatment did not affect the mechanical property of cotton fabrics such as tensile strength.

• Journal of the Korean Applied Science and Technology
• /
• v.19 no.2
• /
• pp.137-144
• /
• 2002

Methyl glycoside oleic acid polyester was successfully prepared from methyl glycosides and methyl oleate by emulsion interesterification in the presence of methyl fructoside oleic acid polyester as an emulsifier. Emulsion interesterification process was optimized to obtain 98% yield of methyl glycoside polyester within $3{\sim}5hr$ at temperatures as relatively low as $90{\sim}150^{\circ}C$ and $20{\sim}200mmHg$ pressure with a five-fold molar ratio of oleic acid methyl ester to methyl glycoside in the presence of 2(w/w)% potassium carbonate and 2O(v/v)% methyl fructoside polyester based on oleic acid methyl ester.

• Bulletin of the Korean Chemical Society
• /
• v.20 no.8
• /
• pp.905-909
• /
• 1999

Reaction of tetrahomodioxa p-phenylcalix[4]arene with ethyl bromoacetate and potassium carbonate in ace-tone leads to the title tetra ester derivative, 7,13,21,27-tetra-phenyl-29,30,31,32 -tetrakis(ethoxycarbonyl)meth-oxy-2,3,16,17-tetrahomo-3,17-dioxacalix[4]arene, its structure was determined by NMR spectra as 1,4-alternate conformation. The molecular structure has been solved by X-ray diffraction methods. The molecule has a conformation with pseudo center of symmetry. The benzene ring A is up, ring C is down, B and D rings are flat with respect to the plane of the macrocyclic ring.