• The Journal of Natural Sciences
• /
• v.6 no.1
• /
• pp.49-54
• /
• 1993

This study was conducted to investigate the influence of various calcium salts on the accumulation of calcium in apple fruits when sprayed on whole tree. Differences in the total calcium contents of fruits were found between calcium sources and cultivars. In 'Tsugaru' , calcium nitrate, calcium chloride, and calcium carbonate were all effective but only calcium chloride and calcium carbonate appeared to be effective in 'Fuji' . Major parts of the applied calcium were accumulated in the feel and outer flesh. Ethylene evolution of fruit was retarded during storage with the increase of total calcium content in 'Fuji' fruit treated calcium acetate.

• Journal of Microbiology and Biotechnology
• /
• v.19 no.12
• /
• pp.1644-1649
• /
• 2009

This study investigates the buffering effects of calcium salts in kimchi on the total acidity, microbial population, and dextransucrase activity. Calcium chloride or calcium carbonate was added to dongchimi-kimchi, a watery radish kimchi, and the effects on various biochemical attributes were analyzed. The addition of 0.1% calcium chloride produced a milder decrease in the pH after 24 days of incubation, which allowed the lactic acid bacteria to survive longer than in the control. In particular, the heterofermentative Leuconostoc genus population was 10-fold higher than that in the control. When sucrose and maltose were also added along with the calcium salts, the dextransucrase activity in the kimchi was elevated and a higher concentration of isomaltooligosaccharides was synthesized when compared with the control. Calcium chloride was determined as a better activator compound of dextransucrase than calcium carbonate, probably because of its higher solubility. Therefore, the results of this study confirm the ability of the proposed approach to modulate the kimchi fermentation process and possibly enhance the quality of kimchi based on the addition of dietary calcium salts.

• Biomaterials Research
• /
• v.22 no.4
• /
• pp.346-351
• /
• 2018

Background: Carbonate apatite ($CO_3Ap$) and silica-calcium phosphate composite (SCPC) are bone substitutes with good prospect for dental application. SCPC creates a hydroxyapatite surface layer and stimulate bone cell function while, $CO_3Ap$ induce apatite crystal formation with good adaptation providing good seal between cement and the bone. Together, these materials will add favorable properties as a pulp capping material to stimulate mineral barrier and maintain pulp vitality. The aim of this study is to investigate modification of $CO_3Ap$ cement combined with SCPC, later term as $CO_3Ap-SCPC$ cement (CAS) in means of its chemical (Calcium release) and physical properties (setting time, DTS and pH value). Methods: The study consist of three groups; group 1 (100% calcium hydroxide, group 2 $CO_3Ap$ (60% DCPA: 40% vaterite, and group 3 CAS (60% DCPA: 20% vaterite: 20% SCPC. Distilled water was employed as a solution for group 1, and $0.2mol/L\;Na_3PO_4$ used for group 2 and group 3. Samples were evaluated with respect to important properties for pulp capping application such as pH, setting time, mechanical strength and calcium release evaluation. Results: The fastest setting time was in $CO_3Ap$ cement group without SCPC, while the addition of 20% SCPC slightly increase the pH value but did not improved the cement mechanical strength, however, the mechanical strength of both $CO_3Ap$ groups were significantly higher than calcium hydroxide. All three groups released calcium ions and had alkaline pH. Highest pH level, as well as calcium released level, was in the control group. Conclusion: The CAS cement had good mechanical and acceptable chemical properties for pulp capping application compared to calcium hydroxide as a gold standard. However, improvements and in vivo studies are to be carried out with the further development of this material.

• Journal of Physiology & Pathology in Korean Medicine
• /
• v.18 no.5
• /
• pp.1387-1390
• /
• 2004

This study was carried out to investigate the solubility of the ingredients of the bilestone in the solution of the traditional oriental medicines. The cholesterol and the calcium carbonate(CaCO₃) were chosen as the ingredients of the bilestone. Coicis Semen, Polygonum aviculare L, Maydis Stigmata, Allium tuberosum Rottler, and Raphanus sativa var. hortensis for. acanthiformis Makino were studied as the oriental medicines for the bilestone. The cholesterol had showed no solubility in all solutions of the traditional oriental medicines, but the calcium carbonate had showed the good solubility in all solutions of the traditional oriental medicines except Coicis Semen.

• Journal of the Korean Chemical Society
• /
• v.54 no.3
• /
• pp.295-299
• /
• 2010

An experimental rig was constructed in order to study the inhibitory effects of two thermal inhibitors namely; stone and calcium carbonate, on Liquefied Petroleum Gas -air flames. This was achieved by measuring the flammability limits of the combustible mixtures before and after the addition of these inhibitors. It was found that calcium carbonate has superior inhibitory effect on the combustible mixture under investigation while, Stone has a lower inhibitory effect than that of calcium carbonate.

• Journal of the Korean Crystal Growth and Crystal Technology
• /
• v.14 no.2
• /
• pp.78-81
• /
• 2004

The nacre of imaged abalone pearls was obtained as a calcium carbonate of aragonite type. This result was same the nacre of natural abalone pearl. From the observation of SEM for the nacre adhered on the pearl nucleus, it was known that the layers of calcium carbonate and conchiolin were stratified. The growth rate of nacre was found to be 0.0056∼0.0074 mm/day, which is twice faster than that of traditional method used shells. The pendant and brooch were manufactured using the imaged abalone pearls.

• Journal of the Korean Ceramic Society
• /
• v.53 no.2
• /
• pp.222-226
• /
• 2016

The synthesis of pure calcium carbonate nanocrystals was achieved using a simultaneous injection method to produce nano particles of uniform size. These were characterized using scanning electron microscopy and powder X-ray diffraction. The nano particles were needle-shaped aragonite polymorphs, approximately 100-200 nm in length. The aragonite polymorph of calcium carbonate was prepared using aqueous solutions of $CaCl_2$ and $Na_2CO_3$, which were injected simultaneously into double distilled water at $50^{\circ}C$ and then allowed to react for 1.5 h. The resulting whisker-type nano aragonite with high aspect ratio (30) is biocompatible and potentially suitable for applications in light weight plastics, as well as in the medical, pharmaceutical, cosmetic and paint industries.

• Journal of the Korean Graphic Arts Communication Society
• /
• v.7 no.1
• /
• pp.49-59
• /
• 1989

This study was made to Investigate the effect of tensile strength(kg/cm$^{2}$), opacity(%), porosity(cc/min) of the paper manufacturing with the freeness properties of NBKP and the calcium carbonate having the different physical and chemical properties. As the results, the opacity and porosity of the freeness of, NBKP, obtained good strength properties from the freeness 65$^{\circ}$SR and the tensile strength from the freeness 85$^{\circ}$SR. The strength properties of paper manufacturing loaded with calcium carbonate appears to be related to the effect of the freeness, and it was obtained the good results at opacity 83.8% in the freeness 85$^{\circ}$SR, tensile strength 3.8kg/m$^{2}$ porosity 87cc/min in the freeness 65$^{\circ}$SR. Addition of 50%, 55%, 60% CaCO$_{3}$ was found to increase slightly the strength properties of paper.

• Journal of Energy Engineering
• /
• v.27 no.1
• /
• pp.51-58
• /
• 2018

In this paper, we reported that the influence of advanced functional mineral filler calcium carbonate ($CaCO_3$) extracted from oyster shell waste, which are rich mineral sources of $CaCO_3$. Oyster Shells, available in abundance, have no eminent use and are commonly regarded as waste. Their improper disposal causes a significant level of environmental concern and also results in a waste of natural resources. Recycling shell waste could potentially eliminate the disposal problem, and also turn an otherwise useless waste into high value added products. Oyster shell waste calcination process to produce pure lime (CaO) which have good anti-microbial property for waste water treatment and then focuses on its current applications to treat the coffee waste and its effluents for biological treatment and utilization as a fertilizers.

• Journal of the Korean Ceramic Society
• /
• v.51 no.2
• /
• pp.127-131
• /
• 2014

Precipitated calcium carbonate(PCC) inorganic fillers for plastic offera higher replacement ratio with improved mechanical properties than any other inorganic fillers. Due to its secure economic feasibility, its fields of application areexpanding. For optimized PCC grain size and polymer replacement ratio, it is good to maintain at least $0.035{\mu}m$ grains and keep double the grain size of distance between particles, depending on the molecular weight and volume replacement rate of the polymer. PCC has unique characteristics, ie, with smaller grain size, dispersibility decreases, and if grain size is not homogenous, polymer cracking occurs. The maximum replacement ratio of PCC is approximately 30%, but in the range of 10 - 15% it produces the highest mechanical strength. When mixed with a biodegradable plastic like starch, it also improves initial environmental degradability.