• Journal of the Mineralogical Society of Korea
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• v.18 no.3 s.45
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• pp.183-194
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• 2005

The mineralogical, physicochemical and thermal properties of the Myogi bentonite occurring in Japan were measured. A adsorption properties of U, Th, Ce and Eu ions on the Myogi bentonite were also investigated in different solution concentrations and pH conditions. The Myogi bentonite showed a strong alkaline character (pH 10.4), very high swelling, viscosity property and CEC, and a slow flocculation behavior due to the strong hydrophilic property. By the thermal analysis, the dehydroxylation of crystal water in bulk and clay fractions of the Myogi bentonite occur at $591^{\circ}C$ and $658^{\circ}C$, respectively, The adsorption experiments of ions such as U, Th, Ce and Eu were conducted for 0.2 g bentonites with 20mL solutions of various concentrations and different pH conditions with pH 3, 5, 7, 9, and 11. As a result, the Myogi bentonite showed excellent adsorption capacities for Ce, Th and Eu ions, whereas U ion showed very low adsorption capacity. Generally, Ce, Th and Eu ions showed the similar adsorption properties for the different concentrated solutions and pH conditions. These adsorption properties seem to be affected by the formation of various forms of chemical species and precipitation as well as ionic exchange reaction and surface adsorptions on smectite. Some associated zeolite minerals perhaps have some effects on the adsorption of U, Th, Ce and Eu on Myogi bentonite.

• Journal of the Korean Chemical Society
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• v.35 no.3
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• pp.189-195
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• 1991

Two crystal structures of dehydrated $Ag_{2.8}ZN_{4.6}-A$ and of its ethylene sorption complex have been determined by single-crystal X-ray diffraction techniques. The structures were solved and refined in the cubic space group Pm3m at 23(1)$^{\circ}$C. Dehydration of two crystals studied were achieved at 400$^{\circ}$C and $2{\times}10^{-6}$ Torr for 2 days and one crystal was treated with 250 Torr of ethylene at 25(1)$^{\circ}$C. The structures of dehydrated $Ag_{2.8}ZN_{4.6}-A$ (a = 12.137(2) ${\AA}$ and of its ethylene sorption complex (a = 12.106(2)${\AA}$) were refined to final error indices, R(weighted) = 0.044 with 237 reflections and R(weighted) = 0.050 with 301 reflections, respectively, for which I > 3${sigma}$(I). 2.8 $Ag^+$ ions are recessed 0.922(2) ${\AA}$ from (111) plane of three 6-ring oxygens into the large cavity where each forms a lateral ${\pi}$ complex with an ethylene molecule. These $Ag^+$ ions are in 2.240(5)${\AA}$ from three framework oxide ions and 2.290(5) ${\AA}$ from each carbon atom of an ethylene molecule. The $Zn^{2+}$ ions occupy two different threefold axis positions of the unit cell. 2.8 $Zn^{2+}$ ions are recessed 0.408(2) ${\AA}$ from (111) plane of the 6-ring oxygens and each $Zn^{2+}$ ion forms a $\pi$ complex with an $C_2H_4$ molecule. The distances between $Zn^{2+}$ ions and carbon atom of ethylene molecule, Zn(2)-C = 2.78(4) ${\AA}$ are long. This indicates that this bond is relatively weak.

• Journal of the Korean Society of Food Science and Nutrition
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• v.33 no.10
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• pp.1715-1719
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• 2004

In order to help the preservation of the unshiu orange and pear, antimicrobial paper incorporating grapefruit seed extract and zeolite was applied to pack fruits. Unshiu orange was packed in a box (24${\times}$24${\times}$22 cm) attached with antimicrobial paper and then stored respectively at l$0^{\circ}C$. Pears were wrapped individually before storage at l$0^{\circ}C$. During the storage, weight loss, pH, total acidity, soluble solid content, microbial load and decay were measured as quality indices. Steady pH increase in unshiu orange was observed to slightly decrease total acidity during the storage with little difference between the packaging treatments. The microbial loads of total aerobic bacteria, and yeast/mold counts were suppressed during storage by the antimicrobial paper packaging, which also contributed to reducing the decayed unshiu orange. Limited reduction of total aerobic bacteria and yeast/mold counts was observed only for initial storage period for the pears wrapped with 9 and 12% antimicrobial agent-added papers. Antimicrobial paper was useful for the reduction of microbial load in unshiu orange and pear without other quality deterioration.

• Journal of Bio-Environment Control
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• v.6 no.2
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• pp.71-79
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• 1997

Commercial Bio- Green(B.G.) functional water was manufactured through a series of processes : water - ultra-purification - adding catalysts - energy imprinting fermenting with energized water ＋ zeolite and others ＋ photosynthetic bacteria in fermenter longrightarrow filtering. Control(0), 5 or 10 liters per plant of B.G. functional water were supplied to the orchard soil under canopy of 10 year- old ‘Tsugaru’/M26 apple trees on March 20, May 20 and June 20, 1995, respectively. pH and content of Ca and Mg of orchard soil were increased by supply with B.G. functional water. However, P$_2$ $O_{5}$, K, and B contents were not influenced by the treatment. At harvest time soluble solid content of flesh tissue and anthocyanin of fruit skin were increased by the treatment. B.G functional water treatment showed higher root activities, and photosynthesis of leaves than that of control. Also B.G. functional water treatment enhanced Ca content in fruit skin and flesh tissues, whereas not affected N, K, and Mg contents. During storage at 4$^{\circ}C$ cold room, the more volume of B.G. functional water supply showed lower bitter pit symptom. Respiration and ethylene evolution in fruit decreased, while fruit firmness increased by the treatment during storage.

• Food Science and Preservation
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• v.6 no.4
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• pp.357-364
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• 1999

Modified atmosphere packaging(MAP) technology was applied to ‘Tsugaru’apple (Malus domestica Borkh) in order to extend the shelf-life of apples during distribution. ‘Tsugaru’apples were packed with the PE film of 40 $\mu\textrm{m}$ thickness(40LD), the PE film modified by the addition of 5% (w/w) zeolite (40CK), and the PE film bags containing the ethylene absorbent (40LP). Quality indices of ‘Tsugaru’apples during storage at 10$^{\circ}C$ were measured in terms of weight loss, soluble solids content, pH, titratable acidity, flesh firmness, peel color and sensory properties. Oxygen, carbon dioxide and ethylene concentration in the film bags changed rapidly at the early stage of storage. Weight loss of the control increased up to 3.0% after 60 days storage while those of the packed apples remained less than 0.6%. No significant differences in soluble solids content and titratable acidity could be found in all the treatments, but significant differences in pH between the control and the packed apples. Higher firmness was kept in 40LD and 40LD than other treatments during storage. Color of the peel changed rapidly in control but slowly in 40LD and 40LP. ‘Tsugaru’apples Packed with Packaging films showed a good visual and sensory quality. Results suggest that packaging treatment with LDPE of 40 $\mu\textrm{m}$ thickness and ethylene absorbent can be used for extending the shelf-life of ‘Tsugaru’apples during distribution.

• The Journal of Engineering Geology
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• v.8 no.2
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• pp.175-188
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• 1998

This paper describes the internal structures and K-Ar ages of fault gouges collected from the Dongnae fault zone. This fault zone is internally zoned and occurs in the multiple fault cores. A fault core consists of thin gouge and narrow cataclastic zones that are bounded by a much thicker damage zone. Intensity of deformation and alteration increases from damage zone through cataclastic zone to gouge zone. It is thought that cataclasis of brittle deformation was the dominant strain-accomodation mechanism in the early stage of deformation to form the gouge zone and that crushed materials in the regions of maximum localization of fault slip subsequently moved by cataclastic flow. Deformation mechanism drastically changed from brittle processes to fluid-assisted flow along the gouge zone as the high porosity and permeability of pulverzied materials during faulting facilitated the influx of the hydrothermal fluids. Subsequently, the fluids reacted with gouge materials to form clay minerals. Fracturing and alteration could have repeatedly taken place in the gouge zone by elevated fluid pressures generated from the reduction of pore volume due to the formation of clay minerals and precipitation of other materials. XRD analysis revealed that the most common clay minerals of the gouge zones are illite and smectite with minor zeolite and kaolinite. Most of illites are composed of 1Md polytype, indicating the products of hydrothermal alteration. The major activities of the Dongnae fault can be divided into two periods based upon K-Ar age data of the fault gouges : 51.4∼57.5Ma and 40.3∼43.6Ma. Judging from the enviromental condition of clay mineral formation, it is inferred that the hydrothermal alteration of older period occured at higher temperature than that of younger period.

• Korean Chemical Engineering Research
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• v.48 no.6
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• pp.768-775
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• 2010

Adsorption dynamics of ethane/ethylene mixture gas and desorption dynamics during the displacement desorption with propane as a desorbent in the column filled with faujasite adsorbent were investigated experimentally and theoretically. The simulation that adopted heat and mass balance and an ideal adsorbed solution theory (IAST) for the multicomponent adsorption equilibrium well predicted the experimental breakthrough curves of the adsorption and desorption. At the adsorption breakthrough experiments, roll-ups of ethane increased as the adsorption pressure increased and the adsorption temperature decreased. During the displacement desorption with propane in the column saturated with ethane/ethylene mixture gas, almost 100% of ethylene was obtained for a certain time interval. The adsorption strength of the desorbent greatly affected the adsorption and re-adsorption dynamics of ethylene. The re-adsorption capacity for ethylene has been greatly reduced when iso-propane, which is stronger desorbent than propane, was used as desorbent. It was found from the simulation that the performance of the displacement desorption process would be superior when the ratio of ${(q_s{\times}b)}_{C_2H_4}/{(q_s{\times}b)}_{C_3H_s}$ was 0.83, that is, the adsorption strengths of ethylene and the desorbent were similar.

• Journal of Animal Science and Technology
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• v.58 no.7
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• pp.24.1-24.7
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• 2016

Background: Clinoptilolite is a natural zeolite with high adsorption capacity for polar mycotoxins such as aflatoxins. The efficacy of clinoptilolite in ameliorating the toxic effects of aflatoxicosis has been proven in monogastric animals, but there is no such evidence for ruminants. The aim of this study was to evaluate, under field conditions, whether the dietary administration of clinoptilolite in dairy cows could reduce the concentration of aflatoxin M1 ($AFM_1$) in bulk-tank milk, in farms with higher than or close to $0.05{\mu}g/kg$ of milk (European maximum allowed residual level). An objective of the present study was also to investigate the effect of particle size of clinoptilolite on aflatoxin binding. Methods: Fifteen commercial Greek dairy herds with AFM1 concentrations in bulk tank milk ${\geq}0.05{\mu}g/kg$ were selected. Bulk tank milk AFM1 was determined prior to the onset and on day 7 of the experiment. Clinoptilolite was added in the total mixed rations of all farms at the rate of 200 g per animal per day, throughout this period. Two different particle sizes of clinoptilolite were used; less than 0.15 mm in 9 farms (LC group) and less than 0.8 mm in 6 farms (HC group). Results: Clinoptilolite administration significantly reduced $AFM_1$ concentrations in milk in all farms tested at an average rate of 56.2 % (SD: 15.11). The mean milk $AFM_1$ concentration recorded on Day 7 was significantly (P < 0.001) lower compared to that of Day 0 ($0.036{\pm}0.0061$ vs. $0.078{\pm}0.0074{\mu}g/kg$). In LC group farms the reduction of milk $AFM_1$ concentration was significantly higher than HC group farms ($0.046{\pm}0.0074$ vs. $0.036{\pm}0.0061{\mu}g/kg$, P = 0.002). As indicated by the Pearson correlation, there was a significant and strong linear correlation among the milk $AFM_1$ concentrations on Days 0 and 7 (R = 0.95, P < 0.001). Conclusions: Dietary administration of clinoptilolite, especially of smallest particle size, at the rate of 200 g per cow per day can effectively reduce milk $AFM_1$ concentration in dairy cattle and can be used as a preventive measure for the amelioration of the risks associated with the presence of aflatoxins in the milk of dairy cows.

• Korean Journal of Mineralogy and Petrology
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• v.35 no.3
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• pp.345-353
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• 2022

This study aimed to fundamentally understand changes of cell parameters of cation-exchanged mordenites using high resolution X-ray powder diffraction for studies that immobilization of various heavy metal cation using synthesis mordenite (Na_6.6Al_6.6Si_41.4O₉₆·20.4H₂O, Na-MOR). As a results of measurement by Thermogravimetric analysis (TGA), it was confirmed that 19.4, 20.4 water molecules per unit cell were present in monovalent-cation substituted MOR (Cs-MOR, Na-MOR), and 21, 23.1, 23.2 water molecules per unit cell were present in divalent-cation substituted MOR (Pb-MOR, Sr-MOR, Cd-MOR). The space group of all the samples were identified as Cmcm belonging to the orthorhombic crystal system. Compared to Na-MOR, starting material, relative peak intensity of (110) and (200) is significantly changed after cation substitution whereas peak position is almost similar. Also, (220) peak that was not found in Na-MOR was clearly observed in Pb-, Cd- and Sr-exchanged MOR. Thus, it was estimated that changes of atomic distribution usually occurred on ab-plane while changes of cell parameters were little. Detailed changes in the cell parameters of cation-exchanged mordenites were derived from whole profile fitting method using the GSAS suite program. Changes in the axial lengths and unit cell volume of cation substitution showed different relationship depending on ionic radius and charge number. In case of monovalent-cation substituted MOR, the length of a-axis increases whereas the length of b- and c-axis decrease by absorbed cation radius. In the case of divalent-cation exchanged MOR, the length of a-axis usually decreases while the length of b- and c-axis increases by cation radius. It was confirmed that unit cell volume of monovalent and divalent cation substituted MORs had an independent tendency by cation radius.

• Journal of the Korean Chemical Society
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• v.37 no.2
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• pp.191-198
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• 1993

The crystal structures of $Cd_{6-}A$ evacuated at $2{\times}10^{-6}$ torr and $750^{\circ}C$ (a = 12.204(1) $\AA$) and dehydrated $Cd_{6-}A$ reacted with 0.1 torr of Cs vapor at $250^{\circ}C$ for 12 hours (a = 12.279(1) $\AA$) have been determined by single crystal X-ray diffraction techniques in the cubic space group Pm3m at $21(1)^{\circ}C.$ Their structures were refined to final error indices, $R_1=$ 0.081 and $R_2=$ 0.091 with 151 reflections and $R_1=$ 0.095 and $R_2=$ 0.089 with 82 reflections, respectively, for which I > $3\sigma(I).$ In vacuum dehydrated $Cd_{6-}A$, six $Cd^{2+}$ ions occupy threefold-axis positions near 6-ring, recessed 0.460(3) $\AA$ into the sodalite cavity from the (111) plane at O(3) : Cd-O(3) = 2.18(2) $\AA$ and O(3)-Cd-O(3) = $115.7(4)^{\circ}.$ Upon treating it with 0.1 torr of Cs vapor at $250^{\circ}C$, all 6 $Cd^{2+}$ ions in dehydrated $Cd_{6-}A$ are reduced by Cs vapor and Cs species are found at 4 crystallographic sites : 3.0 $Cs^+$ ions lie at the centers of the 8-rings at sites of $D_{4h}$ symmetry; ca. 9.0 Cs+ ions lie on the threefold axes of unit cell, ca. 7 in the large cavity and ca. 2 in the sodalite cavity; ca. 0.5 $Cs^+$ ion is found near a 4-ring. In this structure, ca. 12.5 Cs species are found per unit cell, more than the twelve $Cs^+$ ions needed to balance the anionic charge of zeolite framework, indicating that sorption of Cs0 has occurred. The occupancies observed are simply explained by two unit cell arrangements, $Cs_{12}-A$ and $Cs_{13}-A$. About 50% of unit cells may have two $Cs^+$ ions in sodalite unit near opposite 6-rings, six in the large cavity near 6-ring and one in the large cavity near a 4-ring. The remaining 50% of unit cells may have two Cs species in the sodalite unit which are closely associated with two out of 8 $Cs^+$ ions in the large cavity to form linear $(Cs_4)^{3+}$ clusters. These clusters lie on threefold axes and extend through the centers of sodalite units. In all unit cells, three $Cs^+$ ions fill equipoints of symmetry $D_{4h}$ at the centers of 8-rings.