• Title/Summary/Keyword: Water Spaces

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Syntheses and Structures of Two Reduced Open-framework Titanophosphates

  • Zhao, Yongnan;Yu, Jianguo;Kwon, Young-Uk
    • Bulletin of the Korean Chemical Society
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    • v.29 no.4
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    • pp.805-810
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    • 2008
  • Using metallic Ti powder as raw materials and 1,2-diaminocyclohexane (DACH) as the trial template, two novel reduced titanophosphate open-structures were hydrothermally isolated by varying the $H_3PO_4/H_2O$ ratio to adjust the pH value. TiPO-1 crystallizes in orthorhombic Pbca space group with cell parameters a = 21.956(3) $\AA$, b = 8.6268(11) $\AA$, c = 7.2883(9) $\AA$, V = 1380.5(3) $\AA^3$, Z = 4. TiPO-2 crystallizes in triclinic space group P$\bar{1}$ with parameters a = 5.1620(10) $\AA$, b = 8.815(2) $\AA$, c = 10.655(3) $\AA$, $\alpha$ = $99.45^{\circ}$, $\beta$ = $102.94^{\circ}$, $\gamma$ = $91.06^{\circ}$, V = 465.34 $\AA^3$. TiPO-1 is constructed by infinite -Ti-O-Ti-O- linkage that is capped by $PO_4$ groups to form a chain structure with protonated DACH molecules occupying the interchain spaces. TiPO-2 represents a rare 3-D reduced titanophosphate with 12-MR channels. The structure of TiPO-2 is a neutral framework with water molecules located in the channels.

OVERVIEW ON HYDROGEN RISK RESEARCH AND DEVELOPMENT ACTIVITIES: METHODOLOGY AND OPEN ISSUES

  • BENTAIB, AHMED;MEYNET, NICOLAS;BLEYER, ALEXANDRE
    • Nuclear Engineering and Technology
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    • v.47 no.1
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    • pp.26-32
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    • 2015
  • During the course of a severe accident in a light water nuclear reactor, large amounts of hydrogen can be generated and released into the containment during reactor core degradation. Additional burnable gases [hydrogen ($H_2$) and carbon monoxide (CO)] may be released into the containment in the corium/concrete interaction. This could subsequently raise a combustion hazard. As the Fukushima accidents revealed, hydrogen combustion can cause high pressure spikes that could challenge the reactor buildings and lead to failure of the surrounding buildings. To prevent the gas explosion hazard, most mitigation strategies adopted by European countries are based on the implementation of passive autocatalytic recombiners (PARs). Studies of representative accident sequences indicate that, despite the installation of PARs, it is difficult to prevent at all times and locations, the formation of a combustible mixture that potentially leads to local flame acceleration. Complementary research and development (R&D) projects were recently launched to understand better the phenomena associated with the combustion hazard and to address the issues highlighted after the Fukushima Daiichi events such as explosion hazard in the venting system and the potential flammable mixture migration into spaces beyond the primary containment. The expected results will be used to improve the modeling tools and methodology for hydrogen risk assessment and severe accident management guidelines. The present paper aims to present the methodology adopted by Institut de Radioprotection et de $S{\hat{u}}ret{\acute{e}}$ $Nucl{\acute{e}}aire$ to assess hydrogen risk in nuclear power plants, in particular French nuclear power plants, the open issues, and the ongoing R&D programs related to hydrogen distribution, mitigation, and combustion.

A computational study on the removal of the non-isothermal concentrated fume from the semi-enclosed space

  • Chang, Hyuksang;Seo, Moonhyeok;Lee, Chanhyun
    • Environmental Engineering Research
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    • v.22 no.2
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    • pp.216-223
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    • 2017
  • For the prediction of the ventilation rate for removing the non-isothermal concentrated fume from the semi-enclosed space, the computational fluid dynamics (CFD) analysis was done. Securing the proper ventilation conditions in emergency state such as in fire is crucial factor for the protection of the resident in the space. In the analysis for the determining the proper ventilation rate, the experimental study had the limitation for simulating the versatile conditions of fume development. The theoretical and computational method had been chosen as the alternate tool for the experimental analysis. In this study, the CFD analysis was done on the defined model which already had been done the experimental analysis by the previous workers. By comparing the prediction on the plume heights and the ventilation rates by the CFD analysis at, and in the parametric model of $1m^3$ with those of the previous experimental works, the feasibility of the computational analysis was evaluated. For the required ventilation rate analyzed by the CFD analysis was over predicted in 7.1% difference with that of the experimental results depending on the different plume height. With the comparison with the analytical Zukoski model at, the CFD analysis on the ventilation was under predicted in 8.3%. By the verification of the feasibility of the CFD analysis, the extended analysis was done for getting the extra information such as the water vapor distribution and $CO^2$ distribution in the semi-enclosed spaces.

A study on the Occupants' Apprasials of Newly Consturcted Apartment (신축 공동주택의 주거환경에 관한 입주자 평가)

  • 임인순
    • Journal of the Korean housing association
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    • v.4 no.2
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    • pp.73-83
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    • 1993
  • Recently, large APT complexes are newly constructed in Taegu city and among them, large APT complexes aggegate densly espically in Weolsung and Jisan complexes of Dalsuh-gu and Susung-gu districts. The purpose of this thesis is to perform occupants' apprasials about residential environment on the housewifes residing at new constructed APT who seem tn have different apprasials on the residential environment by the zones. The results of the investigations are as follows. 1. House possessed type and house sire got elevated in comparison with them before shifting residence in respect to residential property and it was revealed they moved to short distance in the change of their lands. And most occupants could choose their houses by looting-out and there's some difference in the choice motive according to the zones. 2. As a result of studying the relation between demographic and residential properties, there were deep differe-nces in the Possessed house type before move, possessed house size after move, preferenti-al degree of house and move plan. 3. In the degree of satisfaction on residential environment, the result was high in the order of heating facilities, water-supply and draining facilities and lighting and was low in the order of room's size, interior decoration and soundproofin. According to zones, there was a great difference in the items of room's size, privacy, heating facilities, securi-ty from calamity, ventilation, convenience of traffic and school group and facilities for extracurricular activities and the degree of satisfaction was high in Jisan zone in othe items except for room's size and heating facilities. 4. In the tenants' apprasials on tile inside and outside spaces of the zones, important factors were "Cultural Institutions", "Green Areas", "Level of Welfare Facilities" and "Utility degree of welfare facilities" and in the classification of important factors according to the zones, the first and the third factors were changed each other. I think this is because they attached importance to somethings dissatisfied in present circumstances.

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A Study on Spatial Characteristics in the Paintings of Johannes Vermeer (요하네스 베르메르 회화에 나타난 공간적 특성에 관한 연구)

  • Kim, Jong-Jin
    • Korean Institute of Interior Design Journal
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    • v.17 no.2
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    • pp.22-29
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    • 2008
  • Johannes Vermeer is one of the masters in the 17th century Dutch Genre Painting. Genre Painting represented the mundane everyday life and humble domestic spaces of the time. It was so unique in the history of western art. Most common subjects of the medieval art had been myths, historical heroes, and the christianity up to that time. However, Dutch Genre Painting that was originated from the 16th century Flandre art has fundamentally changed perception of art. Genre Painting was related to the prosperous development of civil society and early capitalism in the Netherlands of the time. In the paintings of Vermeer, there are unique spatial characteristics. This study aims to 'spatially' analyze the representation of everyday space perceived by the painter himself. Three analytical elements were chosen: light, space, and geometry. These elements have crucial roles to construct a space together within which Vermeer tried to express his discoveries as well as perception of the world. Four paintings were selected to be further analyzed in detail: $\ulcorner$A Maid Asleep$\lrcorner$ (1656-57), $\ulcorner$The Little Street$\lrcorner$ (1658-60), $\ulcorner$The Music Lesson$\lrcorner$ (1662-1665), and $\ulcorner$Young Woman with a Water Pitcher$\lrcorner$ (1662). It has been found that there are distinct spatial aspects in his paintings: Structure of Frontal Layers, Diffusion of Light, and Subtle Geometrical Tension. It is hoped that this sort of interdisciplinary research could enrich the related studies in the field of architecture & interior design, and could help to rediscover the everyday world that we live in here and now.

Development of Edible Laminate-Composite Films Using Defatted Mustard Meal and Whey Protein Isolate (탈지겨자씨와 유청단백질을 재료로 사용한 가식성 적층필름의 개발)

  • Kim, Dayeon;Park, Ji Won;Noh, Bong-Soo;Min, Sea Cheol
    • Korean Journal of Food Science and Technology
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    • v.44 no.6
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    • pp.711-715
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    • 2012
  • A laminate-composite film was developed using industry co-products of defatted mustard meal (DMM) and whey protein isolate (WPI). An individually prepared DMM-based film (DMM film) and a WPI-based film (WPI film) were thermally laminated at $130^{\circ}C$ at a rate of 30 cm/min. Microscopic images exhibited that the DMM film and the WPI film were continuously attached in the laminate without void spaces. The tensile strength, elongation at break, and water vapor permeability for the laminate were 0.7MPa, 4.0%, and $6.9g{\cdot}mm/kPa/h/m^2$, respectively. Stretchability and heat seal strength of the laminate were higher than those of the un-laminated DMM film. The film layers of the laminate were physically overlapped, not forming new biopolymer units induced by molecular interactions. The opportunity for DMM films to be used as food packaging materials for wrapping and sealing could be increased by thermal lamination with WPI films, which improves the stretchability and heat sealability of DMM films.

Filterless Removal of PM2.5 Dusts by Condensational Growth (응축성장을 이용한 PM2.5 초미세먼지의 무필터 제거)

  • Pyo, Juwon;Lee, Donggeun
    • Transactions of the Korean Society of Mechanical Engineers B
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    • v.41 no.4
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    • pp.221-228
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    • 2017
  • We proposed a novel method to remove PM2.5 dusts without HEPA filters aiming at applications in kitchens or enclosed work spaces generating PM2.5 at high concentrations. Many workers are exposed to PM2.5 owing to lack of air purification because the high replacement costs of HEPA filters make their application impractical. A key idea is to use the condensational growth of nanoparticles. Once particles grow to the size of a few micrometers, it is much easier to remove them because of their increased inertia. We developed and tested a prototype consisting of an air saturator (equipped with water spray nozzles), a condenser in which humid air was cooled down to make the particles grow, and a multi-impactor assembly for collecting the grown particles.

A Study on the Estimation of Zoysia matrella's Evaporation Using Makkink Model (인공지반에서 금잔디의 증발산량 예측에 관한 연구 -퍼라이트 배합토에서 Makkink의 일사법을 이용하여-)

  • 김도경;황지환
    • Journal of the Korean Institute of Landscape Architecture
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    • v.29 no.1
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    • pp.161-167
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    • 2001
  • The purpose of this study is to find out the difference of Zoysia matrella's evaporation in between 100 percent soil and mixed soil with 50 percent of perlite to create green spaces on the artificial ground. It is believed that the weight against the artificial ground will be reduced, provided the vegetation is possible in the circumstance of the mixed sol with 50 percent of perlite. The study employed a modified Makkink's model by Iwasa who had developed the model for estimating Zoysia matrella's evaporation in the natural ground using the Makkink's formula in 1997 at Chiba University, Japan. The parameter of Makkink's formula is the solar radiation. For that reason, the Makkink's formula is simple and easy to measure the parameter and has a high utility. If the outcomes from mixed soil are close to modified Makkinks formula, the modified Makkink's formula will be applied to estimate in the artificial ground with mixed soil with 50 percent of perlite. Weather observation and actual amount of evaporation of Zoysia matrella have been measured, and the relation between weather condition and actual amount of evaporation had been also investigated. In line with this, we found out that there is a relevant relationship between daily average temperature, the modified Makkink's model by Iwasa, and the actual amount of evaporation. As the results of the experiment, the outcomes from mixed soil with 50 percent of perlite have very high relation to 100 percent soil. In addition, mixed soil has more adhesion with water than natural soil. However, it needs to be adequately maintained in terms of fertilization and damage from disease and harmful insects until the gras fastens its roots into the soil. By using mixed soil with 50 percent of perlite, the load from soil on the artificial ground can be reduced. The study on the growth of the grass throughout the plant vegetation and the actual amount of evaporation in the mixed soil with 50 percent of perlite should be performed in the future.

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The Effects of Soil Particle Composition on Soil Physical Properties and the Growth of Woody Plants (토양의 입도조성이 토양의 물리성 및 목본식물의 생장에 미치는 영향)

  • 이소정;김민수
    • Journal of the Korean Institute of Landscape Architecture
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    • v.25 no.2
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    • pp.54-61
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    • 1997
  • This study has conducted to analyze the crelationship among soil properties and to investigate how they affect soil physical characteristics and plant growth. The experiment of woody plant growth was conducted as follows : Type I was the original soil. Type II, the soil particles smaller than 20${\mu}{\textrm}{m}$ was removed from the original soil. Type III, the soil particles is smaller than 75${\mu}{\textrm}{m}$ was removed from original soil. Wisteria floribunda A.P.DC and Celtis sinensisi Pers. were used for plant growth measurement. 1. Soil type II. the closest to Fuller's curved line, showed high dry bulk density and low in soil pores and saturated hydraulic conductivities. This created poor soil aeration and limited space for the root to growth. When the root did not have sufficient space to grow, there was a lot of physical stress, which hindered the root growth. 2. Soil typeIII was high saturated hydraulic conductivity and a lot of soil pores larger than 10 ${\mu}{\textrm}{m}$. As a result, there were more available spaces for root to spread. It was considered that there was less physical stress for root growth. Therefore, soil typeIII showed significantly greater root growth. 3. Because soil type III has less small particles and saturated hydraulic conductivity was high, and water infiltrates rapidly into the underground when there was rainfall or irrigation. The soil typeIII becomes much stronger soil mechanically due to the less small particles. Therefore, soil typeIII was a suitable material for applying on planting sites where soil compaction is expected.

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Study on Environmental Changes of River in the Suburban Area and Transition of Relations between Residents and River

  • Hiroyuki Kaga;Kumi Kawano;Yasuhiko Shimomura;Noboru Masuda
    • Journal of the Korean Institute of Landscape Architecture International Edition
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    • no.2
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    • pp.185-191
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    • 2004
  • This study dealt with the Kogi River, located in Kaizuka City, Osaka, which has experienced different improvements from the upper through the lower regions, aimed at revealing temporal relations between residents and the river, as well as probing future problems and directions regarding the river in the suburban area, by conducting a survey of local residents. The result showed that, in the upper region where nature remains in its natural state and the good water quality has been maintained, the relations between the residents and the river continued until around 1965; meanwhile in the middle region the relations have been disappearing since about 1955, and in the lower region where the stream has been repeatedly rehabilitated since 1955, there are fewer involvements of the people with the river. It also revealed that the weaker the relations between people and the river became, the larger the number of residents, even in the upper region, who became concerned over the deteriorating river environment after about 1975, and that in the middle and lower areas, about a decade earlier than in the upper area, the number of those who were aware of the environmental deterioration began to increase. Consequently, with an eye to resuming the relations between people and the river in an suburban area, their future challenges would be the space improvements depending on the environmental characteristics of the area; for example, the recovery of grassy banks for the purpose of protection in the lower region; the preservation and maintenance of many waterside woods as well as the creation of open spaces utilizing the river banks in the middle area; and throughout the whole region, the establishment of a system in which the relations between man and the river can be passed down to future generations, by utilizing the local human resources including those who know the former river landscapes or about the playing in and around the river.

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