• International Journal of Highway Engineering
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• v.12 no.2
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• pp.107-113
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• 2010

In this study, the relative effects of low-chloride deicier(LCD) and two other deicing agents on the scaling of concrete were conducted in a series of tests at laboratory accordance with the ASTM C 672. The solutions concentration of deicers tested included 1, 4, 10%. Tap water was used as control. The amount of scaling was evaluated gravimetrically. As test result of deicer solution types, when applied to 4% solutions, surface scaling of concrete after 56 freeze-thaw cycles was produced significantly as about 9 times on LCD solution, as about 18 times on $CaCl_2$ solution, and as about 33 times on NaCl solution comparing with tap water. As test result of deicer solution concentrations, relatively low concentrations (of the 4% by weight) of deicer were produced more surface scaling than higher concentrations (of the 10% by weight) or lower concentrations (of the 1% by weight) of deicer. It show that the damaging concentration is of the order of 3~4% for previous research result. It appears that the mechanism of surface scaling is primarily physical rather than chemical. Also, the effect of chloride deicier types, freeze-thaw cycling, and air contents on the performance of concrete was experimentally investigated. The results show that the concrete specimens subjected to freeze-thaw cycling scaled more severely in exposure to deicing salt than those in non-exposure to deicing salt, weight losses of the specimens tested in exposure to deicing salt were twice as much as those tested in non-exposure to deicing salt. Relative dynamic modulus of elasticity of concrete specimens decreased more quickly in exposure to deicing salt than in non-exposure to deicing salt. Also, relative dynamic modulus of elasticity of concrete specimens in exposure to sodium chloride deicing salt was decreased more quickly comparing with exposure to LCD salt. It is also shown that the chloride contents according to concrete specimen depths was more largely in exposure to LCD salt. When concrete specimen is exposed to chloride deicing salts and freeze-thaw cycling, performance degradation in the entrained air concrete(AE concrete) retarded more considerably comparing with non-entrained air concrete(Non-AE concrete).

• Korean Journal of Fisheries and Aquatic Sciences
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• v.55 no.6
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• pp.817-826
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• 2022

This study was conducted to determinean optimal soaking solution for inhibiting the texture softening of shrimp Litopenaeus vannamei pressured at high temperature (S-P/HT) in a retort, and also to optimize concentrations of 0.5% calcium chloride (CC) and 5.0% potato starch (PS) for preparation of a mixed solution (MS) and soaking time (ST) in the MS. On the basis of the results of expressible drip (4.6%), water holding capacity (95.1%), hardness (18.4 N/cm²) and sensory texture (7.2 score), the MS was found to be the optimal soaking solution for inhibition of texture softening under S-P/HT conditions, The concentrations of CC (X₁, %), PS (X₂, %), and ST (X₃, min) were selected as independent variables, and hardness (Y₁), springiness (Y₂) and sensory texture (Y₃) were selected as dependent variables. The optimal conditions of X₁, X₂, and X₃ were 0.51%, 6.34%, and 364 min, respectively. Under the optimal conditions, the experimental values of Y₁, Y₂ and Y₃ were 18.3±0.8 N/cm², 4.4±0.3 mm and 7.7±0.2, respectively, which did not diffr significantly from the predicted values (P>0.05). In conclusion, the optimized models of X₁, X₂, and X₃ for the preparation of S-P/HT using CC-PS were suitably fitted.

• Korean Journal of Food Science and Technology
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• v.9 no.1
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• pp.13-18
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• 1977

In order to improve the storage ability of Spur Red Delicious apple, calcium ingredients were applied to the apple tree during the growing period, and then the effects of calcium on appearances and respiratory activity of harvest apples were investigated during the storage period. The results of this work were summarized as follows: 1. The freshness of apples treated by calcium compounds reached $73{\sim}78%$, but that of control group was 68% by March of next year. 2. The respiratory rate of the apples that had been applied the high concentration of ammonium sulfate in field during the growing period, was accelerated rather than control group, and that of calcium treatment groups was continuously inhibited during the storage period. 3. The direct foliar application of calcium compounds in the field was more effective than dipping apples in calcium chloride solution for better quality and improving storage ability after harvest. 4. The freshness and hardness relatively not much decreased in calcium treatment groups even after 5 month storage.

• Journal of Physiology & Pathology in Korean Medicine
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• v.27 no.6
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• pp.730-737
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• 2013

The purpose of this study is to investigate vasorelaxant effect of Epimedium koreanum(EK) extract on rabbit carotid artery. In this study, to determine vasorelaxant effect of EK extract on rabbit carotid artery, arterial rings with intact or damaged endothelium were used for experiment using organ bath, and were contracted by norepinephrine(NE). After being contracted, arterial rings were treated with EK extract in a dose-dependent manner To study its mechanism, the contracted arterial rings induced by NE were pretreated with indomethacin(IM), $N_{\omega}$-nitro-L-arginine(L-NNA), methylene blue(MB) or tetraethylammonium chloride(TEA) and 0.1 $mg/m{\ell}$ EK extract was added. To analyze the effect of the EK extract on influx of extracellular calcium chloride($Ca^{2+}$) in rabbit carotid artery, in $Ca^{2+}$-free krebs solution, krebs solution containing 1 mM $Ca^{2+}$ was infused into the contracted arterial ring by NE after pretreatment of EK extract. To measure the cytotoxicity of the EK extract, cell viability of human umbilical vein endothelial cell(HUVEC) was measured by MTT assay, and nitric oxide(NO) was measured by Griess reagent. The EK extract significantly was relaxed the arterial ring with intact endothelium contracted by NE, but the vasorelaxant effect of the EK extract was inhibited in the arterial rings with damaged endothelium. The vasorelaxant effect of the EK extract was not different between the IM-pretreatedand and non-treated arterial rings. The vasorelaxant effect of EK extract were significantly inhibited, when arterial rings were pretreated with L-NNA, TEA, MB. And in $Ca^{2+}$-free krebs solution, increasing of arterial contraction by $Ca^{2+}$ addition were also inhibited by the treatment of EK, but not significant. The treatment of EK extract was increased NO concentration in HUVEC. This study suggested that the vasorelaxant effect of EK extract would be related with EDHF and NO production and increasing of cyclic GMP.

• Journal of the Korean Institute of Landscape Architecture
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• v.45 no.3
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• pp.1-8
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• 2017

The present study aimed to investigate the effect of calcium chloride($CaCl_2$) on the growth and physiological responses of Pinus strobus and the variables that are sensitive to $CaCl_2$. Thus, changes in the visible damage, growth of root collar diameter, plant water content, chlorophyll content and composition, maximum PS II photochemical efficiency, and electron transport rate of P. strobus was analyzed in relation to treatment witih $CaCl_2$. A $CaCl_2$ solution(0.5, 1.0 and 3.0%) was applied in the root zone before leaf unfolding. Leaf browning, defoliation, and drying were observed with $CaCl_2$ application and this pattern was aggravated as the $CaCl_2$ concentration increased and the treatment period became longer. The decrease of growth in root collar diameter and height and leaf water content were observed at $CaCl_2$ 1.0% and 3.0%. The total chlorophyll content indicated that photopigment, PS II photochemical efficiency and electron transport rate significantly decreased at $CaCl_2$ 3.0%. In conclusion, $CaCl_2$ affected leaf water content and led to a decrease of capability in light harvesting and photochemical responses. Also, as a result of the correlation between calcium chloride concentration and growth and physiological response parameters, it was found that the leaf moisture content and the ratio of chlorophyll a and b reflect the damage level of calcium chloride sensitively because their coefficient of determinations were relatively high.

• Journal of Digital Convergence
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• v.14 no.12
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• pp.193-199
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• 2016

MR(magnetorheological) devices for vehicle applications requires the consistent control performance and the reliable operation. However, the corrosion of iron particles consisting the MR fluid can significantly affect on MR properties. This paper presents an effect of the MR particle corrosion on the performance of MR fluids such as shear stress magnitude which is directly concerned with control performance. As a first step, MR particles are corroded by water-calcium chloride solution. The resulting MR particles are examined by scanning electron microscope (SEM) and their molar ratios are analyzed by the energy dispersive X-ray analysis (EDAX). By dispersing the corroded MR particles into silicone oil, the corroded MR fluid is synthesized for evaluation of MR effect change. A rotational viscometer is adopted to measure shear stress magnitude. Finally, it is demonstrated how much the corrosion affect on performances by comparing the normal MR fluid to the corroded MR fluid, from which performance investigation of the MR devices containing the corroded MR particles will be studied in the second phase of this study.

• Journal of Environmental Science International
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• v.30 no.10
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• pp.803-809
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• 2021

This study aimed to investigate the effects of soil amendment (heat-expanded clay and active carbon) and planting of Dendranthema zawadskii var. latilobum on the remediation of salt-affected soil and the plant growth under high calcium chloride (CaCl₂) concentration. The experimental group comprised treatments including Non treatment (Cont.), heat-expanded clay (H), active carbon (AC), planting (P), heat-expanded clay+planting (H+P), active carbon+planting (AC+P). A 200 mL solution of CaCl₂ at a concentration of 10 g·L^-1 was applied as irrigation once every 2 weeks. Compared to the Cont., the incorporation of the 'heat-expanded clay' amendment decreased electrical conductivity of the soil leachate and cation exchange capacity, whereas the growth of Dendranthema zawadskii var. latilobum was relatively increased. These results suggest that the combination of 'heat-expanded clay' amendment and planting will mitigate negative effect of de-icing salts and improve plant growth in salt-contaminated roadside soils.

• Food Engineering Progress
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• v.13 no.4
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• pp.360-364
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• 2009

The onion extractions of MIX treatment (5% $\beta$ cyclodextrin+1% calcium chloride+1% soluble starch mixture solution) using hot water (100${^{\circ}C}$ and 80${^{\circ}C}$) and ultrasonic treatment (25${^{\circ}C}$) incresed L values and decreased a and b values apart from the extraction methods. Extent of the browning reaction as caused by the MIX treatment (0.093) following 100${^{\circ}C}$ water extraction resulted in as low as 31% O.D. level, as compared to the control(0.296). Analysis of the pyruvic acid showed that the control had higher content of pyruric acid than MIX-treated samples. The MIX treatment had lower intensities and higher preferences of browning color and pungency taste compared to the control. The total and coliform microbial counts increased continuously during storage period, while the MIX treatment reduced the number of viable cells. Finally, it was concluded that the MIX treatment was highly effective in suppressing the undesirable browning color and pungent taste after processing, and the microbes increment during storage.

• Applied Chemistry for Engineering
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• v.28 no.3
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• pp.360-368
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• 2017

In order to investigate the durability of high performance polymer concrete composites, polymer concrete specimens were prepared using the ortho-type unsaturated polyester resin (UPR) and iso-type UPR as a polymer binder and the calcium carbonate and silica fine powder as a filler. The durability of polymer concrete specimens was measured by hot water resistance, chemical resistance, pore analysis and SEM observation. The compressive strength of the specimen using the iso-type UPR was higher than that of using the ortho-type UPR, and the compressive strength of the specimen using the silica fine powder was higher than that of using the calcium carbonate filler. From hot water resistance results, it was found that the specimen using the iso-type UPR was superior to that of using the ortho-type UPR and the specimen using the calcium carbonate filler was superior to that of using the silica fine powder. The compressive strength reduction rate was measured after the chemical resistance test and the sodium hydroxide solution showed the highest reduction rate, followed by sulfuric acid, hydrochloric acid and calcium chloride solutions. When using the alkaline solution of sodium hydroxide, the weight reduction rate of the specimen using calcium carbonate was lower than that of using silica fine powder, while for the acidic solutions of sulfuric acid and hydrochloric acid, the weight reduction rate of the specimen using the silica fine powder was lower than that of using calcium carbonate.

• Journal of Pharmaceutical Investigation
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• v.25 no.1
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• pp.37-46
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• 1995

The experiment was designed to investigate the sustained release dosage form of silymarin (SL) from chitosan (CS) carrier. Solid dispersed system was prepared by mixing the drug with chitosan. This solid dispersed system was cross-linked by glutaraldehyde, formaldehyde, acetaldehyde and butylaldehyde, respectively. The dissolution rates of these preparations were compared with each other in vitro. The silymarin was mired with anionic alginate gel and bead was prepared by dropping this mixture to cationic chitosan solution including calcium chloride. Chitosan encapsulated alginate bead after drying in the oven was investigated for the dissolution rate. The dissolution rate of SL-CS mixture was delayed with increase in the amounts of CS and the concentration of aldehyde. The effect on the delay of dissolution rate was in the increasing order of formaldehyde, glutaraldehyde, acetaldehyde, butylaldehyde. The dissolution rate of chitosan encapsulated alginate bead was parallel with the concentration of chitosan in diluted hydrochloric acid solution and delayed with increase in the concentration of chitosan in phosphate buffer solution.