• Journal of Environmental Science International
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• v.11 no.3
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• pp.241-246
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• 2002

One of the Musty and earthy smell compounds in raw water is generally attributed to 2-methylisoborneol (2-MIB). It is well known that activated carbon and oxidants such as $O_3$, Cl $O_2$, are effective ways to control 2-MIB. In isotherm equilibrium experiments, 2-MIB in distilled water was much more adsorbed to the activated carbon(A/C) than raw water containing dissolved organic carbon (DOC). The Freundlich constants(k) of distilled water and raw water were 3.36 and 0.049, and 1/n values were 0.80 and 0.42, respectively. The 2-MIB residual rate were Y = $e^{-0}$.55x/~ $e^{-0}$.54x/ with Ozone( $O_3$) dose by 5 minutes contact time at the 241 and 353 ng/L initial concentrations. The 2-MIB residual rate were Y = $e^{-0}$.32x/~ $e^{-0}$.35x/ with Chlorine dioxide(Cl $O_2$) dose by 15 minutes contact time at the 89 and 249 ng/L initial concentrations. 2-MIB was decreased from 1911 ng/L to 569ng/L by post-ozonation(70%removal efficiency) and removal efficiencies of 2-MIB by the following 4 kinds Granular Activated Carbon(GAC) process such as coal base, coconut base, wood base and zeolite＋carbon base were 95.8, 89.5, 88.4, and 93.7% respectively.ely.

• Journal of Industrial Convergence
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• v.17 no.4
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• pp.15-20
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• 2019

Augmented reality is used in various fields such as culture, education, military, medical. This is a method of recognizing information of an augmented object on the camera. Exhibitions and educational contents for children are already produced in various ways. This research showed the developed contents deliver cultural property information using augmented reality. 'Galgibi AR' and 'Jang Young-sil's Invention AR' allow you to experience cultural assets up close. 'Galgibi AR' is the experience content in the form of 3D blocks. It makes to understand the structure of the zeolite, Galgibi. 'Jang Young-sil's Invention AR' make you to watch out four objects in detail by zooming in, zooming out and rotating. It can also take pictures with the inventions. Both contents implement what we want to deliver accurately through simple content. They increase the enjoyment of cultural heritage through experience contents. This research addressed to help the cultural property information spread to the public by using Augmented Reality.

• Proceedings of the Korea Association of Crystal Growth Conference
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• 1996.06a
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• pp.5-18
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• 1996

The solid state cesium ion source os alumino-silicate based zeolite which contains cerium. The material is an ionic conductor. Cesiums are stably stored in the material and one can extract the cesiums by applying electric field across the electrolyte. Cesium ion bombardment has the unique property of producing high negative ion yield. This ion source is used as the primary source for the production of a negative ion without any gas discharge or the need for a carrier gas. The deposition of materials as an ionic species in the energy range of 1.0 to 300eV is recently recognized as a very promising new thin film technique. This energetic non-thermal equilibrium deposition process produces films by “Kinetic Bonding / Energetic Condensation" mechansim not governed by the common place thermo-mechanical reaction. Under these highly non-equilibrium conditions meta-stable materials are realized and the negative ion is considered to be an optimum paeticle or tool for the purpose. This process differs fundamentally from the conventional ion beam assisted deposition (IBAD) technique such that the ion beam energy transfer to the deposition process is directly coupled the process. Since cesium ion beam sputter deposition process is forming materials with high kinetic energy of metal ion beams, the process provider following unique advantages:(1) to synthesize non thermal-equilibrium materials, (2) to form materials at lower processing temperature than used for conventional chemical of physical vapor deposition, (3) to deposit very uniform, dense, and good adhesive films (4) to make higher doposition rate, (5) to control the ion flux and ion energy independently. Solid state cesium ion beam sputter deposition system has been developed. This source is capable of producing variety of metal ion beams such as C, Si, W, Ta, Mo, Al, Au, Ag, Cr etc. Using this deposition system, several researches have been performed. (1) To produce superior quality amorphous diamond films (2) to produce carbon nitirde hard coatings(Carbon nitride is a new material whose hardness is comparable to the diamond and also has a very high thermal stability.) (3) to produce cesiated amorphous diamond thin film coated Si surface exhibiting negative electron affinity characteristics. In this presentation, the principles of solid state cesium ion beam sputter deposition and several applications of negative metal ion source will be introduced.

• Magazine of the Korea Concrete Institute
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• v.6 no.3
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• pp.201-214
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• 1994

The fracture process zone in concrete is a region ahead of a traction-free crack, in which two major mechanisms, microcracking and bridging, play important roles. The toughness due to bridging is dominant compared to toughness induced by microcracking, so that the bridging is dominani: mechanism governing the fracture process of concrete. Fracture mechanics does work for concrete provided that the fracture process zone is being considered, so that the development of model for the fracture process zone is most important to describe fracture phenomena in concrete. In this paper the bridging zone, which is a part of extended rnacrocrack with stresses transmitted by aggregates in concrete, is modelled by a Dugdale-Barenblatt type model with linear tension-softening curve. Two finite element techniques are shown for the analysis of progressive cracking in concrete based on the discrete crack approach: one with crack element, the other without crack element. The advantage of the technique with crack element is that it dees not need to update the mesh topology to follow the progressive cracking. Numerical results by the techniques are demonstrated.

• Journal of Korean Society of Water and Wastewater
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• v.20 no.3
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• pp.367-375
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• 2006

Sequencing Batch Reactor (SBR) is well adopted for community wastewater treatment for its simplicity, performance and various advantageous treatment options. SBR is now drawing attention for its process modification such as coupled with membrane bioreactor, reverse osmosis or applying different media to achieve high removal efficiency. This study focused on the improved efficiency of carbon, nitrogen and phosphorous removal by applying zeolite materials called bioceramics to the SBR. Two laboratory-scale SBR units were operated in the same operating conditions - one with bioceramics called Bioceramic SBR (BCSBR) and the other without bioceramics used as control. Routine monitoring of COD, TP, $NH_3-N$, $NO_3-N$ was performed throughout this study. COD removal was about 80% to 100% and phosphorous removal was about 60% in the process whereas $NH_3-N$ removal efficiency was found to be 99.9% in the BCSBR unit. Addition of bioceramics also improved sludge characteristics such as sludge dewaterability, specific gravity and particle size. BCSBR can withstand high ammonia shock loading leading to the better treatment capacity of high ammonia containing wastewater. The cause of improved removal efficiencies within the biological reactor could be attributed to the biochemosorption mechanisms of bioceramics. Absorption/adsorption or desorption capacity of bioceramics was tested through laboratory experiments.

• Korean Journal of Environmental Agriculture
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• v.10 no.2
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• pp.128-132
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• 1991

This study was carried out to find a method to remove cadmium from soil and/or attenuate in Cd saturated Soil The chemical form of Cd was influenced by the physico-chemical properties of soil and the adsorption of Cd by soil conformed to the Langmuir isotherm. The order of Cd contents in chemical fractions extracted by several reagents was EDTA > NaOH > $HNO_3$. Flooding, liming and the addition of chelating agents and clay minerals to the contaminated soil seems to desirable in alleviating the harmful effects of Cd on plant growth by reducing Cd content in the $KNO_3$ fraction.

• The Plant Pathology Journal
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• v.19 no.3
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• pp.129-132
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• 2003

Fusarium wilt of cucumber caused by Fusarium oxy-sporum f. sp. cucumerinum is a serious vascular disease worldwide. Biological control of Fusarium wilt in several crops has been accomplished by introducing non-pathogenic Fusarium sup. and other biocontrol agents in soil or in infection courts. In this study, quantitative models were used to determine the biocontrol efficacy of inundatively applied antagonist formulations and the length of their effectiveness in controlling Fusarium wilt of cucumber. Quantitative model of the form [Y=L (1${-exp}^{-kx}$)] best described the relationship between disease incidence (Y, %) and inoculum density (X) of isolates F51 and F55. Isolate F51 was selected as a more virulent isolate based on the extent of its effectiveness in causing the wilt disease. The degree of disease control (Xi/X) obtained with the density of the biocontrol agent (Z), was described by the model [Xi/X=A (1${-exp}^{-cz}$)]. The zeolite-based antagonist formulation amended with chitosan (ZAC) was better at lower rates of application and peaked at around 5 g/ kg of the potting medium, whereas the peat-based antagonist formulation (PA) peaked at around 10 g/kg of the potting medium. ZAC formulation provided significantly better suppression of Fusarium wilt as described by the curvilinear relationship of the type Y= a+bX+c$X^2$, where Y represents percent disease incidence and X represents sustaining effect of the biocontrol agent.

• Journal of the Mineralogical Society of Korea
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• v.30 no.2
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• pp.45-57
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• 2017

Two single crystals of fully dehydrated $Cd^{2+}$-exchanged zeolites Y were prepared by the exchange of ${\mid}Na_{75}{\mid}[Si_{117}Al_{75}O_{384}]-FAU$ ($Na_{75}-Y$, Si/Al = 1.56) with aqueous $0.05M\;Cd(NO_3)_2$ (pH = 3.65) at 294 K, followed by vacuum dehydration at 723 K (crystal 1) and a second crystal, similarly prepared, was exposed to zeolitically dried benzene for 72 hours at 294 K and evacuated (crystal 2). Their structures were determined crystallographically using synchrotron X-rays and were refined to the final error indices using $F_o$>$4{\sigma}(F_o)$ of $R_1/wR_2=0.040/0.121$ and 0.052/0.168, respectively. In crystal $1({\mid}Cd_{36}H_3{\mid}[Si_{117}Al_{75}O_{384}]-FAU)$, $Cd^{2+}$ ions primarily occupy sites I and II, with additional $Cd^{2+}$ ions at sites I', II', and a second site II. In crystal $2({\mid}Cd_{35}(C_6H_6)_{24}H_5{\mid}[Si_{117}Al_{75}O_{384}]-FAU)$, $Cd^{2+}$ ions occupy five crystallographic sites. The 24 benzene molecules are found at two distinct positions within the supercages. The 17 benzene molecules are found on the 3-fold axes in the supercages where each interacts facially with one of site IIa $Cd^{2+}$ ions. The remaining 7 benzene molecules lie on the planes of the 12-rings where each is stabilized by multiple weak electrostatic and van der Waals interactions with framework oxygens.

• Bulletin of the Korean Chemical Society
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• v.21 no.1
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• pp.75-80
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• 2000

The positions of Xe atoms encapsulated in the molecular-dimensioned cavities of fully dehydrated Na-A have been determined. Na-A was exposed to 1050atm of xenon gas at 400 $^{\circ}C$ for seven days, followed by cooling at pressure to encapsulate Xe atoms. The resulting crystal structure of Na-A(7Xe) (a = 12.249(1) $\AA$, $R_1$ = 0.065, and $R_2$ = 0.066) were determined by single-crystal X-ray diffraction techniques in the cubic space group Pm3m at 21(1) $^{\circ}C$ and 1 atm. In the crystal structure of Na-A(7Xe), seven Xe atoms per unit cell are distributed over four crystallographically distinct positions: one Xe atom at Xe(1) lies at the center of the sodalite unit, two Xe atoms at Xe(4) are found opposite four-rings in the large cavity, and four Xe atoms, two at Xe(2) and others at Xe(3), respectively, occupy positions opposite and between eight- and six-rings in the large cavity. Relatively strong interactions of Xe atoms at Xe(2) and Xe(3) with $Na^+$ ions of four-, eight-, and six-rings are observed:Na(1)-Xe(2) = 3.09(6), Na(2)-Xe(3) = 3.11(2), and Na(3)-Xe(2) = 3.37(8) $\AA$. In each sodalite unit, one Xe atom is located at its center. In each large cavity, six Xe atoms are found, forming a distorted octahedral arrangement with four Xe atoms, at equatorial positions (each two at Xe(2) and Xe(3)) and the other two at axial positions (at Xe(4)). With various reasonable distances and angles, the existence of $(Xe)_6$ cluster is proposed (Xe(2)-Xe(3) = 4.78(6) and 4.94(7), Xe(2)-Xe(4) = 4.71(6) and 5.06(6), Xe(3)-Xe(4) = 4.11(3) and 5.32(4) $\AA$, Xe(2)-Xe(3)-Xe(2) = 93(1), Xe(3)-Xe(2)-Xe(3) = 87(1), Xe(2)-Xe(4)-Xe(2) = 91(4), Xe(2)-Xe(4)-Xe(3) = 55(2), 59(1), 61(1), and 68(1), and Xe(3)-Xe(4)-Xe(3) = 89($^{\circ}1$)). These arrangements of the encapsulated Xe atoms in the large cavity are stabilized by alternating dipoles induced on Xe(2), Xe(3), and Xe(4) by eight- and six-ring $Na^+$ ions as well as four-ring oxygens, respectively.

• Journal of the Korean Institute of Landscape Architecture
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• v.30 no.3
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• pp.86-93
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• 2002

The objectives of this research were to investigate the effect of serpentine as a new soil conditioner for growth of turfgrass. To achieve the goal, pure sand or mixtures of sand and serpentine with various ratios were tested for soil physical properties and the growth effects of perennial ryegrass and zoysiagrass growth were compared. Major results of this research are summarized as follows; 1) Hydraulic conductivity of 10~30% serpentine mixtures were observed within the range of 1010~901mm/h which is good for USGA recommendation. Experimental results of pH and EC for various mixtures indicated that the 10% serpentine mixture was the most suitable for turfgrass growth. 2) Perennial ryegass treated with 10% serpentine mixture showed the highest visual quality(p<0.01) among all treatments. And serpentine treatment was more effective to improve visual quality of perennial ryegrass than that of zoysiagrass. The treatment of 10% serpentine had better visual qualities than that of 20% in both of zoysiagrass and perennial ryegrass. Treatment with the right amount of serpentine extends green period for one to two weeks during early winter in both zoysiagrass and perennial ryegrass. 3) In perennial ryegrass, the treatment of 10% serpentine resulted in an increase of total dry weight compare with those of zeolite or barley stone, and also dramatically promoted the dry weight by 15% compared with sand 100%(control). Total dry weight of zoysiagrass treated with 10% serpentine was 9％ higher than that of san. These results indicated that serpentine can be a good soil conditioner for both zoysiagrass and perennial ryegrass when it is blended with sand within a range of 10 to 20% by volume.