• Journal of Yeungnam Medical Science
• /
• v.5 no.2
• /
• pp.59-69
• /
• 1988

This study was designed to investigate the effect of substitution of strontium for calcium on mechanical activity in isolated perfused spontaneously beating rat hearts. The mechanical activity of the hearts of Langendorff's preparation in conditions of low calcium and strontium-substitution for calcium was compared. The effect of norepinephrine and verapamil were also observed in those conditions. The results were as follows : 1. In low calcium, the mechanical activity of the heart preparation was significantly reduced, but when the equimolar strontium was substituted for the reduced calcium, the activity was kept at similar level to the normal condition. 2. When equimolar strontium was substituted for the total calcium in perfusate, the heart preparation stopped its beating, and it was not restored in spite of reperfusion with normal calcium perfusate. 3. Norepinephrine-induced positive inotropic effect was inhibited in low-calcium condition especially with low concentration of norepinephrine, but not in strontium-substitution for calcium. 4. Verapamil reduced the activity of the heart both in low-calcium and strontium-substitution as well as in normal calcium conditions. From above results, it was concluded that strontium served as a substitute of calcium in maintaining mechanical activity and in responsiveness to norepinephrine, and the influx of strontium through cell membrane is inhibited by verapamil as the influx of calcium.

• Korean Journal of Fisheries and Aquatic Sciences
• /
• v.36 no.3
• /
• pp.204-209
• /
• 2003

Utilization of soluble protein recovered from surimi wastewater using calcium powder of cuttle bone were examined. The crude ash content of the heat-induced surimi gel was increased linearly by increasing substitution ratio of recovered protein-ATC toward commercial surimi. Moisture (approximately $76\%$) and lipid $(0.2\%)$ contents were not change, but their protein contents were decreased 15.7 to $14.3\%$ depend on increasing of substitution ratio. The white index of the heat-induced surimi gel by color meter was increased up to $10\%$ of substitution ratio. There were no difference between $0\%\;and\;5\%$ substituted surimi gel in the gel strength. The sensory score on white index and texture of the heat-induced surimi gel did not change in 0 to $10\%$ as a substitution ratio of recovered protein-ATC toward commercial surimi, while decreased in more $15\%.$ The optimal substitution ratio of recovered protein-ATC as a bulking agent was $10\%.$ The heat-induced surimi gel prepared with $10\%$ substitution of recovered protein-ATC was similar to the content and composition of total amino. acids, and superior to calcium content and the ratio of calcium and phosphorus toward those of commercial surimi.

• Advances in concrete construction
• /
• v.11 no.3
• /
• pp.183-192
• /
• 2021

Due to economic and environmental benefits, increasing the substitution ratio of ordinary cement by industry by-products like fly ash (FA) is one of the best approaches to reduce the impact of the concrete industry on the environment. However, as the substitution rate of FA increases, it will have an adverse impact on the performance of cement-based materials, so the actual substitution rate of FA is limited to around 10-30%. Therefore, in order to increase the early-age strength of high replacement (30-70%) low-calcium ultrafine FA blended cement paste, sodium sulfate and calcium sulfate dihydrate were used to improve the reactivity of FA. The results show that sodium sulfate has a significant enhancement effect on the strength of the composite pastes in the early and late ages, while calcium sulfate dihydrate has only a slight effect in the late ages. The addition of sodium sulfate in the cement-FA blended system can enhance the gain rate of non-evaporation water, and can decrease the Ca(OH)2 content. In addition, when the sulfate chemical activators are added, the ettringite content increases, and the surface of the FA is dissolved and hydrated.

• Journal of the Korean Society of Food Science and Nutrition
• /
• v.26 no.6
• /
• pp.1152-1158
• /
• 1997

In order to develop new soysauce using mountain edible herbs, cirsium setidens Nakai and comfrey were added to the raw material of soysauce as a partially substituting ingredient to wheat composing the total nitrogen. The changes of chemical composition of soysauce by the substitution of 1~5% cirsium setidens after four months of aging were similar to those of the control soysauce. On the other hand, total solid content was decreased, while the pH was increased by more than 7%. The total nitrogen and solid contents in the confrey substituted soysauce were increased with the increment of the amount of comfrey, but showed little changes of the pH. The mineral contents of calcium and potassium in the soysauce after four months of aging at 10% substitution of cirsium setidens were increased by 1.7 and 1.4 times, respectively. A significant increase in calcium(2.3 times as compared to the control) was also observed in 7% substitution of comfrey. The amino acid contents such as methionine, tyrosine and histidine were markedly increased at 3% substitution of cirsium setidens. With 5% substitution of comfrey, the contents of tyrosine, glutamic acid methionine were increased by 4.4, 1.8 and 1.7 times, respectively as compared to the control. The results of sensory evaluation revealed that overall acceptability of soysauce with 1~5% substitution of cirsium setidens and 5% of comfrey exceeded other samples composing different ratios of substituting ingredients.

• Journal of Animal Science and Technology
• /
• v.47 no.6
• /
• pp.1009-1016
• /
• 2005

This study was carried out to investigate the effects of substituting NaCl by sodium citrate, potassium lactate and calcium ascorbate (40%) on the quality characteristics of emulsion-type sausages. The pH of emulsion-type sausage of the substitution NaCl with sodium citrate were higher than those of control and the other(P<0.05). The CIE L* value emulsion-type sausage of the substitution NaCl with sodium citrate were higher than those of control and the other(P<0.05). The CIE a* value emulsion-type sausage of the substitution NaCl with potassium lactate were higher than those of control and the other, but CIE b* value were lower(P<0.05). The hardness and gumminess of emulsion-type sausage of the substitution NaCl with sodium citrate were higher than those of control and the other. The Na content of emulsion-type sausage of substitution NaCl with calcium ascorbate were lower than those of control and the other, but Ca content were higher(P<0.05). The K and Fe content of emulsion-type sausage of the substitution NaCl with potassium lactate were higher than those of control and the other(P<0.05). The saltiness of emulsion-type sausage of the substitution NaCl with sodium citrate were higher than those of control and the other(P<0.05). The flavor of emulsion-type sausage of the substitution NaCl with calcium ascorbate were higher than those of control(P<0.05).

• Journal of the Korea Institute of Building Construction
• /
• v.24 no.1
• /
• pp.11-21
• /
• 2024

This research elucidates the fundamental properties of carbon dioxide (CO₂)-cured mortar as influenced by varying substitution rates of blast furnace slag fine powder. The findings indicate that CO₂ curing enhances the formation of calcium carbonate (CaCO₃), contributing to pore reduction and the early development of strength. While calcium hydroxide (Ca(OH)₂) plays a more pivotal role in the primary development of strength compared to CaCO₃, an increase in the substitution rate of blast furnace slag fine powder results in reduced production of Ca(OH)₂. Nonetheless, the maintenance of strength through CaCO₃ formation is observed even after the depletion of Ca(OH)₂, suggesting that the required performance can be sustained post-exposure to the atmosphere following CO₂ curing. It is noted that substitution rates exceeding 50% lead to performance deterioration due to CO₂, highlighting the necessity for careful adjustment of the substitution ratio.

• Food Science of Animal Resources
• /
• v.37 no.3
• /
• pp.456-463
• /
• 2017

The aim of this study was to identify the optimal and superior type of natural calcium for replacing phosphate in cooked ground pork products. To achieve this, 0.5% eggshell calcium (ESC), oyster shell calcium (OSC), marine algae calcium (MAC), or milk calcium (MC) was added to ground pork meat products. The effect of this substitution was studied by comparing the substituted products with products containing 0.3% phosphate blend (control). ESC was considered an ideal phosphate replacer for minimizing the cooking loss, which likely resulted from the increase in the pH of the product. Among the other natural calcium types, OSC treatment did not cause a significant increase in pH, but it lowered the cooking loss. CIE $L^*$ values were higher (p<0.05) in products treated with OSC or MC than the control, and lowest (p<0.05) in the products with ESC. However, products with ESC had higher (p<0.05) CIE $a^*$ and CIE $b^*$ values than the control and products treated with other powders. Compared to the control, products treated with ESC and OSC had similar substitution effects on the textural properties of the products. Therefore, the results of this study suggested that the combined use of ESC and OSC could be a potentially effective method for replacing synthetic phosphate in ground pork products.

• Food Science of Animal Resources
• /
• v.28 no.5
• /
• pp.567-573
• /
• 2008

This study investigated the effects of sodium chloride, potassium chloride, potassium lactate and calcium ascorbate on the physico-chemical and sensory characteristics of sodium-reduced pork patties. Pork patties were prepared in 4 ways: T1 (control, 1.0% NaCl), T2 (0.6% NaCl, 0.4% KCl), T3 (0.7% NaCl, 0.3% potassium lactate) and T4 (0.7% NaCl, 0.3% calcium ascorbate). The pH, cooking loss, total plate counts, TBARS (2-thiobarbituric acid reactive substances), surface color (L, a, b) and sensory characteristics were evaluated. The partial substitution of NaCl with KCl and calcium ascorbate decreased the cooking loss and TBARS values, and enhanced microbial stability. The partial substitution of NaCl with potassium lactate significantly decreased TBARS values and enhanced microbial stability, but significantly increased cooking loss compared to the control after 1 and 4 days of storage. However, the surface color and sensory characteristics were not affected by any of the treatments.

• Journal of the Korean Recycled Construction Resources Institute
• /
• v.4 no.3
• /
• pp.284-291
• /
• 2016

To evaluate the properties of inorganic composites using a great quantity of high-calcium fly ash generated in combined heat and power plants, high-calcium fly ash and F-class fly ash commonly used as concrete admixtures were substituted with binding materials to examine changes of fluidity and compressive strength depending on the substitution ratio for each curing temperature. According to the experimental result, CFA-mixed mortar showed a tendency to reduce its flow unlike FFA-mixed mortar as the substitution ratio was increased, but its flow loss showed smaller than FFA as time passed. As a result of examining compressive strength depending on mixing FA, FFA-mixed mortar had an optimum range within 50% when curing at ambient temperature, but it was found that the compressive strength is reduced when mixing CFA. When curing at high temperature, FFA did not relatively have a great effect on the substitution ratio, but CFA could expect a strength enhancement effect compared with 100% of OPC when using within 25% of binding materials.

• Proceedings of the Korean Magnestics Society Conference
• /
• 2015.11a
• /
• pp.80-80
• /
• 2015