• Restorative Dentistry and Endodontics
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• v.15 no.1
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• pp.1-15
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• 1990

The aim of this study was to investigate the effect of dental therapeutic agent on conduction velocity and threshold current of intradental A- and C-fibers in the cat. Inferior alveolar nerve of cat anesthetized with sodium pentobarbital was exposed and dissected until response of functional single pulp nerve until could be evoked by monopolar electrical stimulation of the crown of the lower left canine teeth. 10ms rectangular pulse was used to determine the threshold current and 1ms rectangular pulse was used to determine conduction velocity. After application of calcium chloride (1, 2, 6M), calcium hydroxide mixed with saline, potassium chloride (0.2, 0.8, 1.6M), eugenol, zinc oxide eugenol to the cavity on the labial surface, conduction velocity and threshold current of single pulp nerve unit were compared with the control. In 10 cats, 24 $A{\delta}$- and 11 C- pulp nerve units were recorded. The mean conduction velocities of $A{\delta}$- and C-fibers were 7.5m/sec (SD=5.8) and 1.2m/sec (SD=0.4), respectively. The mean threshold current was $12.3{\mu}A$ (SD=5.3) for $A{\delta}$-fibers and $24.9{\mu}A$ (SD=8.1) for C-fibers. 1, 2, 6M calcium chloride caused decrease of conduction velocity and remarkable increase of threshold current in $A{\delta}$- and C-fibers. The effect of calcium hydroxide mixed with saline was similar but smaller than calcium chloride solution. 0.2M potassium chloride had insignificant effect. In 0.8M potassium chloride, the threshold current was increased although conduction velocity was not affected. In 1.6M potassium chloride, the threshold current was increased and the conduction velocity was slowed down. Spontaneous activity was recorded frequently for first 5 min but gradually reduced both in $A{\delta}$- and C-fibers. Eugenol had irreversible effect on pulp nerve in that initially there were not certain changes in the conduction velocity and threshold current of $A{\delta}$- and C-fibers, but the responses to electrical stimulation were abruptly disappeared after sustained application and were not recovered. Contrary to eugenol, zinc oxide eugenol did not caused significant increase of the threhold current and caused time dependent decrease of the conduction velocity, and did not show any irreversible change.

• Asian-Australasian Journal of Animal Sciences
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• v.7 no.1
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• pp.63-68
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• 1994

432 samples of raw goat milk were analyzed for sodium, calcium, potassium, chloride, and ashes content. The samples came from 16 pure breed goats, 2 to 4 years of age kept in semi-feedlots. They were basically fed soy bran, cotton bran, triturated Guandu hay and disintegrated corn with its straw and corncob (according to requirements for due preservation and production). The mean values found were: sodium, $45{\pm}10.2mg%$ (24.5-65.6 mg%); potassium, $206{\pm}44.7mg%$ (116.6-295 mg%); calcium, $111{\pm}22mg%$ (66.5-155.4 mg %); ashes, $0.82{\pm}0.06mg%$ (0.68-0.95%); chloride, $235{\pm}39mg%$ (157-313 mg%). Results were related to: a) breed, the Brown and the Saanen revealed superior values for calcium and ashes, b) climate, which in the rain season led to higher contents of sodium, potassium, and calcium when compared to the local dry season, c) time of lactation which increasingly affected the contents of calcium, sodium and ashes, and d) the time between milking, when higher concentration of chloride and ashes were mostly concentrated in the evening and calcium in the morning. These results have important implications in the handling and management of the goat herd.

• International Journal of Highway Engineering
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• v.7 no.3 s.25
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• pp.53-62
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• 2005

Efficient snow-removing work is one of important processes of winter road management. Calcium chloride has been used as a typical deicing agent in Korea. It presents superial performance as snow deicing agents, however it has been known to give serious environmental problem and to deteriorate durability of concrete structure in road by corrosion. The environment-friendly road deicing agents made from the waste material which is liquid phase organic matter that is Ca Mg and reactant of organic acid (nitric acid and propionic acid) have been introduced by number of researchers. They indicated the calcium magnesium salt of organic acids have advantage over the calcium choride in terms of lower production unit cost by resources recycling and can solve environmental problem and durability deterioration of structures. In this study, the deicing performance of calcium magnesium salt of organic acids(CMO) is investigated based on the series of experiments including the test for heat of dissolution, freezing point, ice melting test and ice penetration test.

• Journal of the Korea institute for structural maintenance and inspection
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• v.20 no.4
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• pp.59-67
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• 2016

Concrete is a very useful construction material for the sealing disposal of hazardous substances. In general, mass concrete is applied to these structures. And, the mineral admixtures are recommended for the long term performance. Calcium leaching could be happened due to the contact with pure water in underground structures. Thus, it is needed to evaluate the resistance of calcium leaching for concrete mixed with mineral admixtures. From the test results, the mineral admixtures are effective to the improvement of long term compressive strength and chloride diffusion coefficient in concrete members. When calcium leaching is happened, however, the reduction of compressive strength and chloride penetration resistance is severe than OPC case, the micro pore distribution is adversely affected. Consequently, when the mineral admixtures are applied to underground structures which is exposed to calcium leaching environment, it is desirable to reduce water-to-binder ratio, to expose after the sufficient pozolanic reaction, and to use BFS than FA.

• Korean Journal of Agricultural Science
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• v.46 no.4
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• pp.737-754
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• 2019

Peaches have soft tissues compared to other fruits and are vulnerable to softness, wounds, and loss of marketability due to the weak fruit hardness after harvest. It is necessary to develop a technology to improve the shelf-life of the fruit to expand the distribution of peaches. Calcium compounds and chitosan have an important role in improving the shelf-life of fruit by maintaining the hardness and reducing the respiration rate in peach fruits. In this study, to select useful compounds to improve the shelf-life of peaches, calcium citrate, calcium chloride, calcium nitrate, GH-Ca, OS-Ca, chitosan, and chitosan dissolved in calcium chloride were sprayed onto peach trees. The characteristics of the harvested fruits were investigated after the 'Kumhong' and 'Madoka' peach tree treatments. The hardness of the fruit was kept the highest with the combined treatment and remained high with the calcium citrate, chitosan and calcium nitrate treatments. Ethylene production and respiration were effectively inhibited by the GH-Ca and chitosan treatments. There was no significant difference in soluble solids content and acidity among the fruits treated with the chemicals. The coloration of the fruit skin was not delayed by the calcium and chitosan chemical treatments. Calcium compounds were increased in the fruits and leaves of the peach trees treated with the chemicals compared to the untreated ones. These results suggest that the calcium treatment extended the shelf-life by increasing the calcium content in the leaves and fruits of the peach trees.

• Journal of the Korea Institute of Building Construction
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• v.22 no.1
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• pp.35-43
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• 2022

The aim of this work was to a comparative review the performance of high calcium silicate cement (HSCSC) and that of ordinary Portland cement(OPC) and blast furnace slag cement(S/C). The result of the compressive test confirmed that the compressive strength development rate of high calcium silicate cement concrete at the age of 3 days was 73.6% that of ordinary Portland cement concrete. However, at the age of 28 days, the strength development rate of high calcium silicate cement increased to about 107.0% compared to ordinary Portland cement. In addition, the test of the chloride ion penetration resistance of concrete showed that at the age of 28 days, the passed charge decreased by 73.4% and 93.0%, respectively, in blast furnace slag cement and high calcium silicate cement compared to ordinary Portland cement, and at the age of 56 days, it decreased by 79.1% and 98.3%, exhibiting excellent resistance to chloride ion penetration. In particular, it was confirmed that the rate of decrease in the passed charge with age was higher in high calcium silicate cement than in ordinary Portland cement and blast furnace slag cement.

• Journal of the Korea Concrete Institute
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• v.20 no.6
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• pp.713-719
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• 2008

Various types of coatings have been developed for use as reinforcement in concrete and to resist chloride environment. The most commonly used coatings are inhibited and sealed cement slurry coating, cement polymer compositing coating and epoxy coating. Cement slurry offers passive protection, epoxy coating offers barrier protection whereas polymer coating offers both passive protection and barrier protection. Moreover, damage during handling of the steel may result in disbondment of the epoxy coating, which would increase the risk of localized corrosion. In the present study, inhibiting technique was used to increase the calcium hydroxide content at the interface up to 20%. Calcium hydroxide provides a high buffering capacity that resists a local fall in pH and thus maintains the alkaline environment necessary to prevent chloride corrosion. This study examines the use of a calcium hydroxide coating on the steel surface to enhance the pH buffering capacity of steel-concrete interface. Finally, the chloride threshold level (CTL) of polymer inhibitive coating calcium hydroxide is evaluated.

• Applied Biological Chemistry
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• v.46 no.3
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• pp.183-188
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• 2003

Storage stabilities of soybean curds using cuttle bone powder treated with acetic acid (ATC-soybean curd) and calcium chloride (calcium chloride-soybean curd) as a coagulants were examined. The pH, turbidity of soaking solution, titratable acidity, and viable cell counts of calcium chloride-soybean curd did not change up to 6 days of storage, then decreased rapidly in pH and turbidity and increased rapidly in titratable acidity and viable cell counts, whereas those of ATC-soybean curd did not change up to 9 days of storage, then decreased slowly in pH and turbidity and increased slowly in titratable acidity and viable cell counts. Regardless of coagulants and storage period, white index of soybean curds did not change during cold storage. Hardness and brittleness of calcium chloride-soybean curd decreased rapidly up to 3 days in of storage, remained stable from 3 days to 6 days, then decreased rapidly. Hardness and brittleness of ATC-soybean curd also decreased rapidly up to 3 days in of storage and remained stable from 3 to 9 days, but then decreased slowly. Regardless of coagulants, results of sensory evaluation were similar to those of physicochemical tests. Judging from the above results, shelf-lives were determined as 9 and 6 days for ATC- and calcium chloride-soybean curds, respectively.

• Journal of the Korean Society of Clothing and Textiles
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• v.32 no.6
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• pp.911-917
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• 2008

In this study, we reported the effect of porcine pancreas lipase treatment in the presence of a calcium chloride and Triton X-100 on moisture regain and wettability of PET fabrics. The moisture regain of PET fabrics in the presence of 0.5% surfactant showed a 1.5-fold decrease, compared to the absence of it. Triton X-100 acted as an inhibitor to porcine pancreas lipase hydrolytic activity. The moisture regain and wettability of porcine pancreas lipase treated PET fabrics improved when more than 10mM of calcium chloride was added to the treatment solution. Porcine pancreas lipase treatment caused voids and cracks on PET fabrics.

• Proceedings of the Korean Geotechical Society Conference
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• 2003.03a
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• pp.593-596
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• 2003

The special amendment agent used in this study is mainly composed of inorganic metal salts such as sodium chloride, magnesium chloride, potassium chloride, calcium chloride, thus is friendly to the environment, and has a function of soil-cement-agent solidification. In this study, a series of laboratory and field experiments including unconfined compressive strength, permeability, pH test, constituent analysis, leaching test were carried out to analyse engineering and environmental characteristics of solidified sludge. The results of this research showed that the solidified sludge could be efficiently used in covering, filling, and planting materials.