• Membrane Journal
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• v.25 no.3
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• pp.295-300
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• 2015

PDMS-NaA zeolite membranes were prepared by adding 0~40 wt% NaA zeolite. Based on SEM observation, NaA zeolite was dispersed in the PDMS-NaA zeolite membranes with $2{\sim}5{\mu}m$. The permeabilities of $H_2$ and $N_2$ gases through PDMS-NaA zeolite membranes increased as NaA zeolite contents increased and $H_2$ gas had better permeabilities than $N_2$. The selectivity ($H_2/N_2$) of PDMS-NaA zeolite membranes increased as NaA zeolite contents increased.

• Membrane Journal
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• v.25 no.2
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• pp.107-114
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• 2015

PTMSP-NaA zeolite composite membranes were prepared by adding 0~50 wt% NaA zeolite to PTMSP. The membranes were characterized by FT-IR, $^1H$-NMR, GPC, DSC, TGA, SEM. The permeabilities of $H_2$ and $N_2$ gases through PTMSP-NaA zeolite composite membranes was studied as a function of NaA zeolite contents. According to TGA measurements, when zeolite was inserted into the polymer, weight loss temperature and weight loss wt% of PTMSP-NaA zeolite composite membranes were decreased. Based on SEM observation, NaA zeolite was dispersed in the PTMSP-NaA zeolite composite membrane with the size $2{\sim}5{\mu}m$. The permeability of PTMSP-NaA zeolite composite membranes increased added as NaA zeolite content increased. On the contrary, the selectivity ($H_2/N_2$) of the composite membranes decreased as NaA zeolite content increased. PTMSP-NaA zeolite composite membrane showed better permeability and selectivity ($H_2/N_2$) of $H_2$ and $N_2$ than PTMSP-NaY zeolite composite membrane.

• Journal of the Korean Crystal Growth and Crystal Technology
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• v.9 no.3
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• pp.309-314
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• 1999

A microporous zeolite-type tianosilicate (TS-1), new catalysis elements, was synthesized by differents of the reactant solution pH. The range of reactant solution pH has from 10.0 to 12.4 TS-1 Zeolite (ETS-10), having a large pore (8~10 ${\AA}$), was synthesized at 10.4 of pH, since TS-1 Zeolite (ETS-4), having a small pore (3~5 ${\AA}$), was synthesized at 11.5 of pH. Also the two materials simultaneously existed at the intermediate pH. Crystallization, physico chemical characteristics of synthesized TS-1 Zeolite were investigated by XRD, XRF, SEM and FT-IR techniques.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.1 no.2
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• pp.33-40
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• 2000

The present invention relates to a absorption rotor for removed VOC(volatile organic compound) and humidity in semiconductor clean room system. A absorption rotor medium is made by NaX zeolite and TS-1 zeolite formed on a honeycomb matrix of ceramic papers. The crystallization of NaX zeolite was hydrothermal reaction, and NaX zeolite crystals of a uniform particle size of 5$\mu$m were synthesized that NaX zeolite seed crystals (2~3$\mu$m) added in a batch composition at levels of 3~15 wt$\%$. The seeding resulted in an increase in the fraction of large crystals compared with unseeded batches and successfully led to a uniform NaX zeolite crystal. The microporous zeolite-type titanosilicate(TS-1) was synthesized by different of the reactant solution pH. The pH range of reactant solution has been changed from 10.0 to 11.5 TS-1 zeolite (ETS-10), having a large pore(8~10 $\AA$), was synthesized at 10.4 of pH, since TS-1 zeolite (ETS-4), having a small pore(3~5$\AA$), was synthesized at 11.5 of pH.

• Environmental Engineering Research
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• v.24 no.2
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• pp.246-253
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• 2019

This study was conducted to explore the optimum proportion of zeolite and zeolite-kaolin as additives to cement clinker and gypsum samples, while maintaining the strength properties of produced environmentally sustainable cements. According to the British standard method, zeolite was added to cement clinker in proportions of 5-12% and 10-12% by weight, respectively, in the preparation of samples of zeolite-containing cement and zeolite-kaolin-based cement. Kaolin was used as a second additive as 10-20% of the total weight. The compressive strength tests were performed on base cement samples according to a standard procedure given in ASTM C109 Compressive Strength of Hydraulic Cement. These values were compared with those of the reference sample and the Omani allowable limits. The results indicated that the best compressive strength values were obtained with 88% cement clinker, 5% gypsum, and 7% zeolite for the zeolite-containing cement. Quantities of 70% cement clinker, 5% gypsum, 10% zeolite, and 15% kaolin gave the best results for zeolite-kaolin-based cement, resulting in a substitution of than 25% cement clinker. The study concluded that the partial cement clinker replacement using zeolite/kaolin combination may have a great influence on the reduction of $CO_2$ emission and energy saving in cement manufacturing.

• Bulletin of the Korean Chemical Society
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• v.20 no.5
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• pp.587-591
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• 1999

A molecular dynamics simulation study on the structure and dynamics of Na+ ions in non-rigid dehydrated Na12-A zeolite framework at 298.15 K was conducted using the same method reported in previous studies on rigid and non-rigid Na12-A zeolite frameworks. The agreement between the experimental and calculated results for the zeolite-A framework atoms of structural parameters for non-rigid dehydrated Na12-A zeolite is generally quite good, and for the adsorbed Na+ions the agreement is acceptable. The calculated bond lengths are generally in good agreement with the experimental results and other theoretical data. The calculated IR spectrum by Fourier transform of the total dipole moment autocorrelation function shows two major peaks around 2700 cm-1 and 7000 cm-1. The former appeared in the calculated IR spectra of non-rigid zeolite-A framework only system and the latter remains unexplained except, perhaps, indicating a new formation of a vibrational mode of the framework due to the adsorption of Na+ ions. The peaks above 6200-6800 cm-1 in non-rigid dehydrated Nal2-A zeolite are much larger than those in non-rigid dehydrated H12-A zeolite.

• Korean Journal of Soil Science and Fertilizer
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• v.28 no.4
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• pp.340-349
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• 1995

Effects of the zeolite particle size on the soil chemical properties and on rice growth was investigated on the pot with the loamy sand (Sadu series) and silty clay loam(Paju series) soils. All the zeolite treatments brought the increase of unhulled grain yield on the both loamy sand and silty clay loam soils. Unhulled grain yield increased with increasing the amount of zeolite applied and with decreasing the amount of particle size of zeolite applied on both soils. Unhulled grain yield increased significantly by 11.1% (22.79g/head) with 2ton/10a of smaller than $106{\mu}m$ size zeolite on the loamy sand soil and on the silty clay loam soil, yield increased by 9.3% (24.98g/head) with 1.5ton/10a of smaller than $106{\mu}m$ size zeolite. CEC, pH and contents of exchangeable cations of the soil after experiment were raised by increasing the amount of zeolite and also by decreasing the particle size of zeolite at both soil. At the heading stage, the zeolite treatments improved the growth of rice plant compared to control. The nutrient contents(T-N, Ca, Mg, K, Na), except phosphorus, in the rice plant grown on the zeolite treated soils were higher than control plot.

• New & Renewable Energy
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• v.8 no.2
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• pp.24-32
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• 2012

Natural gas hydrates have a high potential as the 21st century new energy resource, because it have a large amount of deposits in many deep-water and permafrost regions of the world widely. Natural gas hydrate is formed by physical binding between water molecule and gas mainly composed of methane, which is captured in the cavities of water molecules under the specific temperature and pressure. $1m^3$ methane hydrate can be decomposed to the methane gas of $172m^3$ and water of $0.8m^3$ at standard condition. Therefore, there are a lot of practical applications such as separation processes, natural gas storage transportation and carbon dioxide sequestration. For the industrial utilization of methane hydrate, it is very important to rapidly manufacture hydrate. However, when methane hydrate is artificially formed, its reaction time may be too long and the gas consumption in water becomes relatively low, because the reaction rate between water and gas is low. So in this study, hydrate formation was experimented by adding natural zeolite and Synthetic zeolite 5A in distilled water, respectively. The results show that when the Synthetic zeolite 5A of 0.01 wt% was, the amount of gas consumed during the formation of methane hydrate was higher than that in the natural zeolite. Also, the natural zeolite and Synthetic zeolite 5A decreased the hydrate formation time to a greater extent than the distilled water at the same subcooling temperature.

• Journal of the Korean Society of Food Science and Nutrition
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• v.42 no.12
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• pp.2028-2034
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• 2013

The effect of zeolite on the quality properties of fresh and broiled pork loin was investigated using 84 pigs that were fed with different feed ration of zeolite (0, 0.5, 1.0 and 2.0% zeolite) for 3 months. The pH of fresh pork loin fed with 0% and 2.0% zeolite was 5.95, which was higher than those of others (P<0.05). The cooking loss of fresh pork loin fed with 0.5% and 1.0% zeolite were 26.24% and 26.42%, respectively, which was higher than those of others (P<0.05). The dissolution crude lipid of 1.0% zeolite (3.11%) was highest, but that of 0% zeolite was lowest (P<0.05). L and a values were highest in fresh pork fed with 1.0% zeolite, however, b value was highest in fresh pork fed with 2.0% zeolite (P<0.05). In the results of L value of the broiled pork loin, the feed ration with 0% zeolite was highest (75.49) and decreased as the feed ration of zeolite increased (P<0.05). The a and b values were highest in broiled pork fed with 0.5% zeolite (P<0.05). The hardness, springiness, gumminess and chewiness of fresh and broiled pork loin fed with 2.0% zeolite were highest and increased as the feed ration of zeolite increased (P<0.05). In the result of sensory evaluation in broiled pork loin, color preference was increased as the feed ration of zeolite increased (P<0.05). Taste preference was highest in the 1.0% zeolite (10.70), followed by 2.0% (8.72), 0.5% (7.64), and 0% zeolite (6.44) (P<0.05). Flavor and appearance preferences were not significantly different between the groups. Texture preference was decreased as the feed ration of zeolite increased. The overall preference was highest in the 1.0% with zeolite (10.80), followed by 0.5% (10.04), 0% (8.41), and 2.0% (7.92) with zeolite (P<0.05). In conclusion, the optimal feed ration of zeolite for broiled pork loin was between 0.5 and 1.0% zeolite.

• Korean journal of food and cookery science
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• v.30 no.2
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• pp.193-199
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• 2014

The purpose of the study was to investigate the quality characteristics and sensory properties of fresh and boiling pork shoulder at different feed ration of zeolite (0, 0.5, 1.0 and 2.0%). All of the dietary zeolite groups had significantly higher pH than the control; 0.5% zeolite (6.14) had the highest pH. Cooking loss was significantly higher in the control compared to other treatments; further, the loss, increased as the feed ratio of zeolite addition increased. The cooking loss of fresh pork shoulder fed with 0.5% zeolite (22.47%) was significantly lower than other treatments. The dissolution crude lipid of 0.5% zeolite was the lowest, but was not significant. In the Hunter's color value of fresh pork shoulder, the L and a values were significantly higher in 0.5% zeolite compared to other treatments, whereas the b value was significantly higher in 2.0% zeolite. In the Hunter's color value of boiling pork shoulder, the L and b values with 0.5% zeolite were significantly higher compared to other treatments; however, the a value was not significantly different between groups. The hardness, springiness, cohesiveness, gumminess and chewiness of fresh pork shoulder were significantly increased as the feed ration of zeolite increased. These properties, except for springiness in boiling pork shoulder were significantly increased as the feed ration of zeolite increased. Furthermore, sensory characteristics of color, taste, flavor, appearance and overall preference were significantly higher in boiling pork shoulder with 0.5% zeolite compared to other treatments. Also, texture preference, which was decreased as the feed ratio of zeolite increased, was higher in the control compared to other treatments. In conclusion, the quality characteristics and sensory properties of pork shoulder meat were enhanced with the dietary supplementation of zeolite.