• Proceedings of the Korean Society of Propulsion Engineers Conference
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• 2017.05a
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• pp.445-450
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• 2017

ZPP(Zirconium Potassium Perchlorate) is an igniter composed of potassium perchlorate as oxidizing agent and zirconium as fuel with a Viton binder. ZPP is used to provide ignition in the aerospace, propulsion, automotive industries. This research is investigated for the manufacturing process and characteristics analysis of the ZPP such as the performance and shape/calorimetry/pressure characteristics of the ZPP on PMD(Pyrotechnic Mechanical Device). During the production of ZPP, the mixing process was designed so that the ZPP could be produced in uniform particle size and shape by mixing the raw materials at high speed.

• Nutrition Research and Practice
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• v.16 no.1
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• pp.74-93
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• 2022

BACKGROUND/OBJECTIVES: There has been an increased interest in determining calcium magnesium, sodium, and potassium's distinct effects on hypertension over the past decade, yet they simultaneously regulate blood pressure. We aimed at examining the association of dietary calcium, magnesium, sodium, and potassium independently and jointly with hypertension using National Health and Nutrition Examination Survey data from 2007 to 2014. MATERIALS/METHODS: The associations were examined on a large cross-sectional study involving 16684 US adults aged>20 years, using multivariate analyses with logistical models. RESULTS: Sodium and calcium quartiles assessed alone were not associated with hypertension. Potassium was negatively associated with hypertension in the highest quartile, 0.64 (95% confidence interval [CI], 0.48-0.87). When jointly assessed using the high and low cut-off points, low sodium and corresponding high calcium, magnesium, and potassium intake somewhat reduced the odds of hypertension 0.39 (95% CI, 0.20-0.76). The sodium-to-potassium ratio was positively associated with hypertension in the highest quartile1.50 (95% CI, 1.11-2.02). When potassium was adjusted for sodium intake and sodium-to-potassium ratio assessed among women, increased odds of hypertension were reported in the highest quartile as 2.02 (95% CI, 1.18-3.34) and 1.69 (95% CI, 1.12-2.57), respectively. The association of combined minerals on hypertension using dietary goals established that men meeting the reference intakes for calcium and exceeding for magnesium had reduced odds of hypertension 0.51 (95% CI, 0.30-0.89). Women exceeding the recommendations for both calcium and magnesium had the lower reduced odds of 0.30 (95% CI, 0.10-0.69). CONCLUSIONS: Our results suggest that the studied minerals' association on hypertension is stronger when jointly assessed, mostly after gender stratification. As compared to men, women increased their risk of hypertension even with a low sodium intake. Women would also reasonably reduce their risk of developing hypertension by increasing calcium and magnesium intake. In comparison, men would somewhat be protected from developing hypertension with calcium intake meeting the dietary goals and magnesium exceeding the nutritional goals.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.36 no.3
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• pp.220-224
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• 2003

Effect of the ingestion of porphyran extracted from Porphyra yezoensis on calcium, magnesium and potassium contents in serum and tissue was investigated using hyperlipidemic and hypercholesterolemic rats. The contents of calcium magnesium and potassium in serum of rats fed porphyran for four weeks were higher than those of the control group. The contents of calcium and potassium were decreased with increasing a porphyran level while magnesium content was increased. Liver calcium contents in an $1\%$ porphyran group were significantly (p<0.05) higher than those in the control group, and magnesium contents in a $10\%$ porphyran group were higher than those in the control group. Kidney calcium and magnesium contents in rats fed porphyran were significantly (p<0.05) high compared with the control group. However, potassium content in kidney was Increased as a porphyran level was increased in diet. Spleen calcium and potassium contents were significantly lower in the porphyran groups than those in the control group. Rats fed the $5\%$ porphyran diet had higher magnesium content in spleen than any other diets. The results showed that diets supplemented with several porphyran levels had variable effects on the contents of calcium, magnesium and potassium in serum and tissue of hyperlipidemic rats.

• Korean Journal of Community Nutrition
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• v.17 no.6
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• pp.737-751
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• 2012

The purpose of this study was to assess sodium and potassium intakes and urinary excretion of adults in Busan and to evaluate the relationship of urinary sodium/potassium excretion (UNa/UK) to the status of anthropometric, blood pressure, urine analysis, and nutrient intake of subjects. Nutrient intake by 24-h recall, 24-h UNa/UK were measured with 87 adults aged 20-59 yrs (42 men and 45 women). The mean intakes of sodium and potassium were 3915.4 mg and 3093.9 mg, respectively. The mean 24-h UNa/UK was 3457.0/1680.4 mg. UNa showed significant positive correlations with sodium intake (p < 0.001, p < 0.001), sodium/potassium ratio (p < 0.001, p < 0.01), UK (p < 0.001, p < 0.001), and UNa/UK ratio (p < 0.05, p < 0.01) in men and women and with age, BMI, systolic blood pressure (SBP) and diastolic blood pressure in women (p < 0.05, p < 0.05, p < 0.05, p < 0.05). The UK showed significant positive correlations sodium intake (p < 0.001, p < 0.001), UNa (p < 0.001, p < 0.001) in men and women and with sodium density in men (p < 0.001) and with age, intakes of protein and potassium in women (p < 0.01, p < 0.05, p < 0.05). Mean SBP was lowest in the second quartile and highest in the fourth quartile of UNa. Mean UNa in the second, third, and fourth quartiles were 2821.1 mg, 3621.3 mg, and 5456.4 mg, respectively. Mean SBP in the second, third, and fourth quartiles were 115.8 mmHg, 120.7 mmHg, and 125.9 mmHg, respectively. Based on the results, UNa was related to sodium intake, UK, and SBP. We conclude that nutritional education for the reduction of high sodium intake is needed in the general population to prevent and control adverse blood pressure levels.

• Korean Journal of Veterinary Research
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• v.29 no.3
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• pp.245-251
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• 1989

In order to manifest the presence of Na-K pump and its property on the unfertilized egg membranes of mouse, membrane potential was recorded under the physiological condition (at $37^{\circ}C$ and 4mM $Ca^{2+}$). After an induction of superovulation, the fresh eggs with zona pellucida were collected from mouse oviduct. Transient hyperpolarization as pump action was recorded after the switch into the high potassium perfusate (15mM $K^+$) from K-free perfusate, and the difference between membrane potential observed just before the perfusion of high potassium solution and the maximal membrane potenlial during the perfusion of high potassium solution was regard as pump activities. The results observed were as follows, 1. Resting mombrane potential was depolarized under the treatment of $10^{-5}M$ ouabain. 2. Pump activities of the unfertilized mouse eggs were $-3.38{\pm}0.61mV$ ($Mean{\pm}SD$, n=6), recorded as transient hyperpolarization due to the electrogenic property. 3. Pump activities were blocked by both treatment of $10^{-5}M$ ouabain and perfusion of Nafree solution, while increased by high $Na^+$ (300mM) perfusion ($-7.45{\pm}0.75mV$, n =2). 4. Hyperpolarization due to pump activity was not altered by $Mn^{2+}$. 5. Above results confirm the presence of ouabain-sensitive Na-K pump, which affected the membrane potential directly, on the unfertilized egg membranes of mouse.

• Journal of the Korean Ceramic Society
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• v.22 no.3
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• pp.60-66
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• 1985

The formation mechanism of unstable alkali and its existing states in the clinker were studied. The relation of unstable alkali content vs. other water-soluble components porosity and the distributionof potassium were investigated. The results are as follows :1) Two states of unstable alkali seem to exist in clinker ie compounds of $K_2O-Al_2O_3$ system and free $K_2O$ 2) The content of water-soluble $Al_2O_3$ tends to increase with increase of unstable alkali content, 3) Most of alkalies in clinker are concentrated in liquid phase at high temperature. Therefore it is possible to make various $K_2O-Al_2O_3$ system compounds according to the content of $K_2O$ in the liquid phase of clinker. In this experiment we found out a $K_2O-Al_2O_3$ compound of high $Al_2O_3$ content (34%) and high $K_2O$ content (33%) in clinker with 1.09% unstable alkali. 4) The porosity of clinker tends to increase with increase of unstable alkali content. 5) The amount of trapped alkali vapor may increase in closed pore in the clinker with high alkali and low $SO_3$ condecent. Therefore free $K_2O$ is the condensed alkali on the wall of closed pore in the clinker.

• Proceedings of the IEEK Conference
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• 2004.08c
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• pp.787-791
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• 2004

We investigated field-effect ion-transport devices based on carbon nanotubes by using classical molecular dynamics simulations under applied external force fields, and we present model schematics that car be applied to the nanoscale data storage devices and unipolar ionic field-effect transistors. As the applied external force field is increased, potassium ions rapidly flow through the nanochannel. Under low external force fields, ther nal fluctuations of the nanochannels affect tunneling of the potassium ions whereas the effects of thermal fluctuations are negligible under high external force fields. Since the electric current conductivity increases when potassium ions are inserted into fullerenes or carbon nanotubes, the field effect due to the gate, which can modify the position of the potassium ions, changes the tunneling current between the drain and the source.

• Bulletin of the Korean Chemical Society
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• v.34 no.1
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• pp.42-48
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• 2013

Potassium N-heterobiaryltrifluoroborates were successfully prepared via a selective Cu-catalyzed C-N coupling reaction. The $BF_3K$ moiety was well tolerated under the reaction conditions involving CuI and dimethyl-ethylenediamine (DMEDA) in the presence of DMSO. The Pd-catalyzed Suzuki-Miyaura cross couplings of potassium N-heterobiaryltrifluoroborates with bromoarenes were studied to prepare the N-heterotriaryl compounds. Moreover, homocoupling, iodination, and hydroxylation of potassium N-heterobiaryltrifluoroborates provided the corresponding products in high yields.

• Journal of the Korean institute of surface engineering
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• v.26 no.6
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• pp.299-306
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• 1993

The characteristic of synthesized potassium hexatitanate and manufacturing of thin film type matrix for battery was studied. After ball milled the mixture with 1:4 of $K_2CO_3$ and TiO2, mixsture was sintered at 85$0^{\circ}C$ and its product was confirmed with XRD. Adding the PTFE to the obtained potassium hexatitanate according to there various ball-mill time to control its particle size, thin film type matrix was manufactured. The high-est wettability of 50% was found with 12 hour ball milled powder containing 10w/o of PTFE and also it shown good mechanical properties. The matrix with $K_2O$$\cdot$$6TiO_2$ whisker shown 170% of wettability. Thed char-acteristics of matrix made by whisker and powder mixture were compared with the investigation of bubbled pressure and pore size distribution to improve its mechanical properties.

• Journal of the Korean Society of Groundwater Environment
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• v.5 no.2
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• pp.66-79
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• 1998

This study purposes to elucidate the characteristics of local water quality and the evolutional process of the spring water have been studied with the samples from 55 selected springs, from the coast region to the Baegrogdam, a caldera lake of Halla mountain in Cheju Island. Results of hydrochemical analyses in the 55 spring water show that Gwaneumsa is pollued with high hydrogen concentration, and spring waters from Yusuarmchun, Jangsumul, Dukjisemmul, Sinch'onk'nmul, Youngchunsa, Woonyangchun, Harwontongmul, Dongheamul, Seakdalsengsu, Andukkyekok, Dotimul, Kinmul, Harkangmul and Jungkeummul are polluted by the pollution sources from the surface surrounding ground. Spring waters of Samyang3suwon, Meungbusa, Sernurungmul, Tosanmul, Jungkeummul, Kwakgimul, Aewolharmul, Konemul and Nokgomul are also polluted from the sea water intrusion. The electrical conductivity, pH and the concentration of nitrate nitrogen and bicarbonate increase when the precipitation increases, but the concentration of sodium, chloride and sulphate decrease when the precipitation increases. The concentrations of potassium, magnessium and calcium are nearly independent of the precipitaion. Quality characteristics of spring water show complicated group of spring water through piper's trilinear diagram. The high mountain region consists of groups of sodium or potassium type and bicarbonate type; the middle mountain region consists of groups of sodium or potassium type and no dominant type; the low mountain consists of groups of no dominant type and sulfate or nitrate type; the coast region consists of groups of sodium or potassium type and chloride type or no dominant type. These characteristics indicate that the spring waters are changed from bicarbonate type in the high and middle mountain regions into non-bicarbonate type in the coastal region, as the precipitated waters flow downslope.