• Journal of the Korean Ceramic Society
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• v.38 no.2
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• pp.143-151
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• 2001

Ca/LiCl-KCl/CaCrO$_4$열 전지계의 양극재료로서 BCT(Body-Centered Tetragonal) 결정구조를 갖는 CaCrO$_4$분말을 GNP로 합성하고, SEM, TEM, XRD를 이용하여 그 미세구조를 분석하였다. GNP 공정에 의한 CaCrO$_4$분말은 단일상으로 0.5$mu extrm{m}$ 이하의 입자 크기를 가지며 균일하게 분포한 반면, 기존의 분말 혼합법은 높은 하수 온도 및 장시간의 하소 조건을 필요하므로 미세한 분말 합성이 어렵고 pellet 형태로 만들었을 때 GNP 분말에 비해 비표면적이 현저하게 작기 때문에 전극 재료로써 유리하지 못하다. Ca/LiCl-KCl/CaCrO$_4$계의 전기 화학적인 특성을 평가해본 결과 전지셀을 Ca/DEB(LiCl-KCl+CaCrO$_4$+SiO$_2$)와 같은 DEB 형태로 만들었을 때 $600^{\circ}C$의 온도에서 2.0 V이상 (<100 mA/㎤)의 안정한 전압이 5분 이상 유지되었다. 그러나 3층 전극 셀(Ca/LiCl/KCl/ CaCrO$_4$)에서는 동일한 온도에서 2.0 V이상 (<100 mA/㎤)의 전압이 7분 이상 유지되었으나 불안정한 전압 변동 및 낮은 peak voltage로 인해 DEB 셀의 전지 특성이 더 우수한 것으로 생각된다. 양극 재료의 제조 방법의 관점에서 볼 때, 동일한 DEB(Depolarizer : Electrolyte : Binder=25 : 70 : 5 wt%) 조성의 셀 구성시, GNP 분말은 분말 혼합법에 의한 분말보다 반응 표면적이 훨씬 크기 때문에 GNP 양극 활 물질의 DEB 셀에서의 전지 수명이 더 길었다.

• Journal of the Korean Society of Propulsion Engineers
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• v.24 no.1
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• pp.58-63
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• 2020

THPP is a type of metallic complex explosive used in initiators, consisting of TiH₂ and KClO₄. In this case KClO₄ includes ClO₄^- which is a harmful substance that may cause thyroid dysfunction or tumors. In this study KIO₄ is applied to a new type of environmentally friendly explosive as a substitute to the conventional KClO₄. Tests were carried out to see if KIO₄ can be made a successful replacement for KClO₄.

• Journal of Nuclear Fuel Cycle and Waste Technology(JNFCWT)
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• v.7 no.4
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• pp.207-212
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• 2009

In this study, a thermal behavior of $PrCl_3$ as one of the lanthanide chlorides in LiCl-KCl molten salts was investigated in an oxidizing condition. First, a thermo-gravimetric analysis (TGA) of $PrCl_3$ was carried out by an injection of $O_2$ gas. Based on the results, an oxidation of $PrCl_3$ in the molten salts was performed by sparging $O_2$ gas with changing temperatures. According to the TGA data of $PrCl_3$, a dissociation of $PrCl_3$ occurred rapidly by about $380^{\circ}C$ and a conversion of $PrCl_3$ to $PrCl_3$ was completed at about $600^{\circ}C$. The thermal behavior of $PrCl_3$ in LiCl-KCl molten salts by sparging $O_2$ gas was similar to that of $PrCl_3$ in the TGA test, and PrOCl as a insoluble compound in the molten salts was precipitated into the bottom of the molten salts. A conversion of $PrCl_3$ to PrOCl in the molten salts occurred actively at a higher temperature than $650^{\circ}C$. And it would be possible to estimate a conversion status of $PrCl_3$ to PrOCl by measuring a $Cl_2$ concentration in a flue gas generated from an oxidation test of $PrCl_3$ in LiCl-KCl molten salts.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.9 no.3
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• pp.163-168
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• 1976

Three species of Rhodophyceae namely Chondrus ocellatus, Grateloupia filicina and Gigartina tenella were collected from the coast of Haeundae, Busan, on June 33, 1975. And analysed with respect to the content of carrageenan and such chemical characteristics as the content of sulphate and 3, 6-anhydrogalactose, the solubility in potassium chloride solution. In addition, the same chemical properties were tested on the fractions separated by the different concentration of potassium chloride. Carrageenan content in Chondrus ocellatus was relatively higher than two other samples. All the samples showed more than thirty five percent. The Gigartina-carrageenan showed the highest 3,6-anhydrogalactose content among three samples of carrageenan obtained from different species, and the lowest marked from the Grateloupia-carrageenan. In comparison of the solubility of carrageenan in potassium chloride solution, the precipitation yields at 0.125M potassium chloride were marked in order of Chondrus-carrageenan, Grateloupia-carrageenan, and Gigartina-carrageenan, and the yields at 0.125 M to 2.0 M potassium chloride were in Gigartina-carrageenan, Grateloupia-carrageenan, and Chondrus-carrageenan, and the yields from the soluble fraction at 2.0 M potassium chloride were in order of Grateloupia-carrageenan, Gigartina-carrageenan, and Chondrus-carrageenan. It is noteworthy from the result of characteristics of carrageenans that, 3,6-andydrogalactose content was closely related to the solubility of carrageenans in potassium chloride solution and to the sulphate content which might affect reversibly.

• Journal of Food Hygiene and Safety
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• v.11 no.2
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• pp.83-87
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• 1996

The objective of this study is to investigate the direct effects of green tea catechins(GTC) on vascular smooth muscle tension and 45Ca2+ Uptake in rat aorta. The methods used in this study are isometric tension measurements using physiograph, Lanthanum method for 45Ca2+(2 uCi/ml) uptake measurement in rat aorta. GTC modified tension induced by 40 mM KCl or 1 uM norepinephrine in rat aorta. Low concentrations of GTC(<0.5mg/ml) increased tension by 40 mM KCl or 1 uM norepinephrine, individually. However, high conecentration of GTC(>0.5 mg/ml) inhibiited tension by 40 mM KCl or 1 uM norepinephrine, individually. GTC increased 45Ca uptake induced by 40 mM KCl in a dose-dependent manner. From these results, GTC has the dual actions in vascular smooth muscle in vitro. Low concentrations of GTC augments tension by K or norepinephrine. However, high concentrations of GTC inhibits tension by K or norepinephrine GTC may have Ca2+ channel activation, action, which may result in unphysiological vasodilation by Ca2+ overload in vascular smooth muscle.

• Asian-Australasian Journal of Animal Sciences
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• v.31 no.1
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• pp.123-128
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• 2018

Objective: This study was performed to determine effects of different curing salts on the quality of salamis and to assess feasibility of using NaCl-alternative salts. Methods: Various types of curing salts (KCl or $MgCl_2$) as well as NaCl (sun-dried or refined) were incorporated for processing of salamis. The proximate composition, fatty acids, nucleotide-related compounds, and free amino acids of the salamis were analyzed during 40 days of ripening. Results: The substitution of NaCl by KCl caused higher fat and ash content, but lower moisture content of the salami after 20 days of ripening (p<0.05). Compared with the sun-dried NaCl, use of KCl in salami also led to greater inosine 5'-monophosphate whereas refined NaCl had more inosine (p<0.05). KCl-added salami also had a higher C12:0, C17:1, and C20:0 than other types of salami (p<0.05). $MgCl_2-added$ salami had higher content of free amino acids compared to the other salamis (p<0.05). Conclusion: Alternative curing salts such as KCl and $MgCl_2$ could substitute NaCl in consideration of quality factor of a fermented meat product. Especially replacement of NaCl with KCl will be a suitable strategy for developing relatively low sodium salami products without compromising product quality.

• Toxicological Research
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• v.32 no.2
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• pp.159-173
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• 2016

Crickets have been attracting considerable interest in the field of nutrition and toxicology due to the global exhaustion of food resulting from a growing population. The cricket is normally eaten in several countries after roasting, similar to the grasshopper; however, safety evaluation data on cricket powder is limited. Here, we performed general toxicity studies of cricket powder including a single, 2-week repeated dose range evaluation test, a 13-week repeated oral dose toxicity test in Sprague-Dawley rats, a single oral dose toxicity test in Beagle dogs, and a skin sensitization test in guinea pigs following the Organization for Economic Cooperation and Development test guidelines 406 and 408 in addition to Good Laboratory Practice. To investigate the NOAEL and target organs of cricket powder, Sprague-Dawley rats were allocated to 4 groups: vehicle control, 1,250 mg/kg, 2,500 mg/kg, 5,000 mg/kg dose test groups and cricket powder was administered over 13 weeks after single dose and dose range finding studies in rats based on the results of the single oral administration toxicity study in rats and Beagle dogs. The results of the study showed that the NOAEL of cricket powder was over 5,000 mg/kg for both sexes of rats without adverse effects in a 13-week repeated oral toxicity study and there was no skin hypersensitivity reaction. Therefore, our results reveal that crickets can be widely used as a new substitute food or nutrient resource.

• The Korean Journal of Physiology and Pharmacology
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• v.4 no.6
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• pp.479-486
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• 2000

The aim of this study was to clarify the mechanism of the inhibitory action of carbon monoxide (CO) on contraction, by measuring cytosolic $Ca^{2+}$ level $([Ca^{2+}]_i)$ and ionic currents in guinea-pig ileum. CO (10%) inhibited 40 mM KCl-induced contraction and this effect was blocked by ODQ $(1\;{\mu}M),$ a soluble guanylyl cyclase (sGC) inhibitor. CO inhibited the 40 mM KCl-induced contraction without changing $[Ca^{2+}]_i.$ Cumulative addition of KCl induced a graded increase in $[Ca^{2+}]_i$ and muscle tension. In the presence of CO, cumulative addition of KCl induced smaller contraction than in the absence of CO. On the other hand, the increase in $[Ca^{2+}]_i$ induced by cumulative addition of KCl was only slightly decreased in the presence of CO, and the $[Ca^{2+}]_i-tension$ relationship shifted downwards. Using the patch clamp technique with a holding potential of -60 mV, we found that CO had little effect on the peak Ba currents $(I_{Ba})$ when voltage was stepped from -60 mV to 0 mV. In addition, CO showed no effect on the depolarization-activated outward $K^+$ currents in the all potential ranges. We conclude that CO inhibits smooth muscle contraction mainly by decreasing the $Ca^{2+}$ sensitivity of contractile elements via a cGMP-dependent pathway, not by involving L-type $Ca^{2+}$ and outward-potassium currents in guinea-pig ileum.

• The Korean Journal of Physiology and Pharmacology
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• v.2 no.1
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• pp.63-68
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• 1998

Nitric oxide (NO)-mediated relaxation in vascular smooth muscle involves not only activation of guanylate cyclase but also hyperpolarization of the membrane. It has been shown that depolarization decreases the [$Ca^{2+}$] sensitivity of myosin light chain kinase in arterial smooth muscle, and nitric oxide (NO)-mediated relaxation was attenuated in this situation. However, why potassium inhibits or attenuates the action of EDRF/NO is not clear. Therefore, we investigated the magnitude of relaxation and cGMP contents using measures known to release NO, such as photorelaxation, photo activated NO-mediated relaxation, and NO-donor (SNP)-mediated relaxation in porcine coronary arterial rings in which contractile conditions were made by different degree of depolarization, i.e., contraction in response to U46619 or U46619 plus KCl. In all cases, the magnitude of relaxation was significantly greater (P＜0.05) in U46619-contracted rings than in U46619+KCl-contracted ones. Although accumulation of cGMP was evident with three measures employed in the present study, no difference was found in cGMP contents between U46619 and U46619+KCl conditions, indicating that the diminished relaxation in KCl containing solution is cGMP-independent mechanism(s). To understand this further, cytosolic $Ca^{2+}$ changes due to NO were compared in rat thoracic aorta by exploiting photoactivated NO using streptozotocin (STZ) that was contracted with either NE or KCl. Fura-3 $[Ca]_{cyt}$ signal caused by NO was small and transient in high $K^+$-, but large and sustained in NE-contracted aorta. The inhibitory potency of STZ expressed in terms of $IC_{50}$ was 5.14 and 3.88 ${\mu}M$ in NE and in high $K^+$, respectively. These results suggest that modification of the cellular mobilization of $Ca^{2+}$ rather than cGMP levels may be an important mechanism for the NO-mediated relaxation when vascular membrane is depolarized, such as atherosclerosis and hypertension.

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