• Analytical Science and Technology
• /
• v.19 no.4
• /
• pp.309-315
• /
• 2006

Two piperazine-templated metal sulfate complexes, $(C_4N_2H_{12})[Ni(H_2O)_6](SO_4)_2$, I and ($C_4N_2H_{12}$) $[Co(H_2O)_6](SO_4)_2$, II, have been synthesized by hydro/solvothermal reactions and their crystal structures analyzed by single crystal X-ray diffraction methods. Complex I crystallizes in the monoclinic system, $P2_1/n$ space group, a=12.920(3), b=10.616(2), $c=13.303(2){\AA}$, ${\beta}=114.09(1)^{\circ}$, Z=4, $R_1=0.030$ for 3683 reflections; II: monoclinic $P2_1/n$, a=12.906(3), b=10.711(2), $c=13.303(2){\AA}$, ${\beta}=114.10(2)^{\circ}$, Z=4, $R_1=0.032$ for 4010 reflections. The crystal structures of the piperazine-templated metal(II) sulfates demonstrate zero-dimensional compound constituted by diprotonated piperazine cations, metal(II) cations and sulfate anions. The structures of complex I and II are substantially isostructural to that of the previously reported our piperazine-templated copper(II) sulfate complex $(C_4N_2H_{12})[Cu(H_2O)_6](SO_4)_2$. The central metal(II) atoms are coordinated by six water molecules in the octahedral geometry. The crystal structures are stabilized by three-dimensional networks of the $O_{water}-H{\cdots}O_{sulfate}$ and $N_{pip}-H{\cdots}O_{sulfate}$ hydrogen bonds between the water molecules and sulfate anions and protonated piperazine cations. Based on the results of thermal analysis, the thermal decomposition reactions of the complex I was analyzed to have three distinctive stages whereas the complex II proceed through several stages.

• Korean Journal of Organic Agriculture
• /
• v.24 no.4
• /
• pp.719-733
• /
• 2016

This study was carried out to investigate the effect of no-tillage on sequential cropping supported from recycling of first crop ridge on the productivity of crop and physical properties of soil under green house condition. This study is a part of "No-tillage agriculture of Korea-type on recycled ridge". From results for distribution of soil particle size with time process after tillage, soil particles were composed with granular structure in both tillage and no-tillage. No-tillage soil in distribution of above 2 mm soil particle increased at top soil and subsoil compared with tillage soil. Tillage and one year of no-tillage soil were not a significant difference at above 0.25 mm~below 0.5 mm, above 0.5 mm~below 1.0 mm, and above 1.0 mm of water-stable aggregate. Two years of no-tillage soil was significantly increased by 8.2%, 4.5%, and 1.7% at above 0.25 mm~below 0.5 mm, above 0.5 mm~below 1.0 mm, and above 1.0 mm of water-stable aggregate, respectively, compared with one year of no-tillage. Bulk density of top soil was $1.10MG\;m^3$ at tillage and $1.30MG\;m^3$ at one year of no-tillage. Bulk density of top soil was $1.14MG\;m^3$ at two years and $1.03MG\;m^3$ at three years of no-tillage, respectively. Bulk density of subsoil was a similar tendency. Solid phase ratio in top soil and subsoil was increased at one year of no-tillage compared with tillage soil, while soil phase ratio decreased at two and three years of no-tillage. Pore space ratio in tillage top soil (58.5%) was decreased by 8.5% at compared with no-tillage soil (51.0%). Pore space ratio was 56.9% and 61.2% at two and three years of no-tillage soil, respectively. Subsoil was a similar tendency. Gaseous phase ratio was decreased at one year of no-tillage soil, and increased at two and three years of no-tillage soil compared with tillage soil. Liquid phase ratio in top soil was increased at one year of no-tillage (28.3%), and decreased at two years (23.4%) and at three years (18.3 %) of no-tillage soil compared with tillage soil (24.2%). Subsoil was a similar tendency. Liquid phase ratio in subsoil was increased than top soil.

• Korean Journal of Remote Sensing
• /
• v.39 no.5_1
• /
• pp.563-576
• /
• 2023

In this study nitrogen dioxide (NO₂), formaldehyde (HCHO) from the Ozone Monitoring Instrument (OMI) and TROPOspheric Monitoring Instrument (TROPOMI), OMI/ Microwave Limb Sounder (MLS) tropospheric column ozone (TCO), and Airkorea ground-based O₃ data were analyzed to examine the photochemical reaction relationship between tropospheric ozone and its precursors nitrogen oxides (NOx) and volatile organic compounds (VOCs). As a result of analyzing the trend of long-term changes from 2006 to 2020 using OMI satellite data, TCO showed an increasing trend, NO₂ steadily decreased, and HCHO continued to increase in Northeast Asia. In addition, formaldehyde nitrogen dioxide ratio (FNR; HCHO/NO₂ ratio), an indicator of ozone sensitivity, is gradually increasing, which means that the VOC-limited regime is decreasing. This study conducted a sensitivity analysis of ozone generation using TROPOMI FNR and ground-based ozone (O₃) over the recent years (2019~2022) to identify the possible cause for the continuous increase of ozone in Korea. Similar to the previous studies, VOC-limited and transitional regimes appeared in megacities, and VOC-limited regimes also appeared in areas where major power plants were located. In VOC-limited regimes, in other words, areas where NOx is excessively saturated, the reduction in NOx emissions may have weakened the ozone titration and thus led to the increase of ozone. Therefore, VOC emissions should be reduced in the short term rather than NOx emissions to reduce ozone concentrations under the VOC-limited regime.

• Journal of the Korean Institute of Landscape Architecture
• /
• v.46 no.1
• /
• pp.72-85
• /
• 2018

This study focused on cases that led sustainable urban development through the construction and utilization of organic greenery systems linking green spaces of urban peripheries with metropolitan areas. To that end, Berlin - Brandenburg's regional parks in Germany and Milan's Raggi Verdi, a radial green axis project, in Italy were selected for analysis as case studies. As frameworks for this analysis, this study has established existing infrastructure accessibility and linkage, recycling and cooperative management. The results of the case study analysis are as follows: First, the specialized spatial strategy based on the individuality of the green space outside the city rather than a uniform landscape was used as the foundation of the sustainable development plan. Second, physical linkage from the center of the city to the periphery contributed to the sustainable development of the overall metropolis by improving the economic value of the surrounding area as well as ecological and environmental values. Third, the central management system was established to reduce the administrative inconvenience caused by multiple administrative districts in the green space of urban periphery. The implications of applying the above results to Seoul, Korea are as follows. First, it is necessary to establish a differentiation strategy by re-establishing the identity of a green landscape in the urban periphery, because the green spaces of Seoul's periphery are dispersed and mostly have a repetitious mountain landscape. Also, it is necessary to actively link peripheral mountains and urban green areas to create ecological value and economic value, and ultimately to help the sustainable development of the city. Finally, building an integrated management system is required to solve fragmented green space management departments in most of the urban periphery's green spaces. In conclusion, this study shows the significant possibility that the sustainable development of a metropolis can be derived from the utilization, linkage, and management of the green space in the urban peripheries, which is extraordinary compared to normal centralized urban development.

• Archives of design research
• /
• v.19 no.1 s.63
• /
• pp.201-214
• /
• 2006

Modern society is an age of vagueness and confusion. In addition, vagueness, complexity and variety are seen throughout art including modern philosophy, literature, and environmental design. A phenomenon like this shows that modern society has integrated different components as an organic relationship frequently crossing the boundary of fields. This feature can be regarded as hybrid related with accepting contradictory components and binding them into one under relationship between part and whole. As new design concept, presented are attitude to accept the two instead of attitude to select one of the alternatives, abundance instead of dearness, and ambiguity instead of simplicity. This principle has a crucial influence on creative design providing opposing contradiction and several alternative plans as non-deterministic form not completed one and, above all, useful information in mutual dependence and mutual relationship. When it comes to hybrid, therefore, a strategy is needed to consider layer of several fields getting out of standardizing space into a single space. As an event of this situation and concept, space experience means behaving freely based on experience of users' body. It can be known that this experience brings about users' more dynamic experience in comparison with the experience of seeing environmental design from a viewpoint of visual ism on the existing simplicity. Such a practical experience is subjective, synesthetic, and non-observational one. Therefore, hybrid has brought active users to the stage, which is distinguished from synesthesia felt through body's experience, not through observational attitude and visual space which achieve former balance and harmony with non-determination. That's because hybrid creatures are turning to a product resulted from creative imagination instead of from reappearance which makes text visualized. Such experience performed by user's active participation collapses the boundary between special elite-centered art and daily life and it is the present progressive form showing creation process of future events and new esthetic experience.

• Journal of the Korean Wood Science and Technology
• /
• v.45 no.5
• /
• pp.580-587
• /
• 2017

Woodfiber insulation board can be considered as a one of the key material for low energy consumption, comfortable and safety construction of residential space because of its eco-friendly and high thermal insulation performance. This study was carried out to investigate the formaldehyde (HCHO) total volatile organic compounds (TVOC) emission properties and combustion shapes by flame test of low density fiberboards (LDFs) prepared with different adhesives. HCHO TVOC emission and combustion properties of LDFs prepared by melamine urea formaldehyde (MUF), phenol formaldehyde (PF), emulsified methylene diphenyl diisocyanate (eMDI) and latex resin adhesives were measured by desiccator method, 20 L chamber method, and flame test, respectively. As results, LDFs manufactured by MUF, eMDI and latex resin adhesives satisfied the Super $E_0$ grade of HCHO emission performance except PF resin. Furthermore, TVOC emission of all LDFs were satisfied the Korean indoor air quality standard (below $400{\mu}g/m^2{\cdot}h$). Especially, LDF with eMDI resin adhesive showed the lowest HCHO and TVOC emissivity, that $0.14mg/{\ell}$, $12{\mu}g/m^2{\cdot}h$, respectively. However, eMDI emitted the small amount ($3{\mu}g/m^2{\cdot}h$) of toluene in VOC components. In the flame test, LDF with MUF resin adhesives showed the most favorable shape after flame test compare to LDFs prepared other adhesives. Based on HCHO and TVOC emission, and combustion shapes, MUF resin adhesive may be recommended to prepare LDF for insulation purpose.

• Journal of Korean Society of Forest Science
• /
• v.96 no.1
• /
• pp.89-95
• /
• 2007

This study was carried out to evaluate soil properties by regions from chestnut (Castanea crenata Sieb. et Zucc) stands in Gyeongnam province. Soil physical and chemical properties were measured from soil samples of top 20 em collected from three hillslopes (upper, middle, lower) of the chestnut stands in six regions (Jinjusi, Sacheonsi, Sancheonggun, Hadonggun, Goseonggun, Hapcheongun) where are major chestnut cultivation areas throughout the province. Soil properties were significantly different among regions (p<0.05), while were not significantly different among hillslopes (p>0.05). Soil bulk density, soil pore space, soil pH, organic matter content, total nitrogen, available phosphorus, and CEC were significantly different among regions (p<0.05). Soil bulk density was significantly lower (p<0.05) in Hadonggun ($0.96g/cm^3$ than in other regions ($1.12{\sim}1.22g/cm^3$). Soil pH was below pH 5.03 in most regions and Sancheonggun showed the lowest soil pH value (pH 4.62), followed by Jinjusi, Hadonggun, Hapcheongtm, Goseonggun, and Sacheonsi. Organic matter content was highest in Hadonggun (6.46%), while other regions ranged between 2.93% and 3.47%. Total nitrogen content showed a similar trend like the organic matter content. Available phosphorus was above 100 ppm in Jinjusi, Hadonggun and Sancheonggun, but Sacheonsi showed the lowest concentration (15 ppm) among the regions. Cation Exchange Capacity (CEC) was above 10 cmolc/kg in Goseonggun and Hadonggun, but below 8.6 cmolc/kg in Jinjusi and Hapcheongtm. Potassium content ranged between 0.07 and 0.14 cmolc/kg, and magnesium was above 0.66 cmolc/kg in all regions. The results indicate that soil property in chestnut stands was different among regions in Gyeongnam province. This suggested that the chestnut stands should be managed by the fertilization application reflected in the variability of regional soil property in chestnut stands.

• Clean Technology
• /
• v.28 no.3
• /
• pp.218-226
• /
• 2022

As a result of the recent social transformation towards a hydrogen economy and carbon-neutrality, the demands for hydrogen energy have been increasing rapidly worldwide. As such, eco-friendly hydrogen production technologies that do not produce carbon dioxide (CO₂) emissions are being focused on. Among them, ammonia (NH₃) is an economical hydrogen carrier that can easily produce hydrogen (H₂). In this study, Ru/Al₂O₃ catalyst coated onmetallic monolith for hydrogen production from ammonia was prepared by a dip-coating method using a catalyst slurry mixture composed of Ru/Al₂O₃ catalyst, inorganic binder (alumina sol) and organic binder (methyl cellulose). At the optimized 1:1:0.1 weight ratio of catalyst/inorganic binder/organic binder, the amount of catalyst coated on the metallic monolith after one cycle coating was about 61.6 g L^-1. The uniform thickness (about 42 ㎛) and crystal structure of the catalyst coated on the metallic monolith surface were confirmed through scanning electron microscopy (SEM) and X-ray diffraction (XRD) analysis. Also, a numerical optimization regression equation for NH3 conversion according to the independent variables of reaction temperature (400-600 ℃) and gas hourly space velocity (1,000-5,000 h^-1) was calculated by response surface methodology (RSM). This model indicated a determination coefficient (R²) of 0.991 and had statistically significant predictors. This regression model could contribute to the commercial process design of hydrogen production by ammonia decomposition.

• Journal of the Korean association of regional geographers
• /
• v.5 no.1
• /
• pp.25-75
• /
• 1999

This study concern with the pattern of Pusan Station Shopping District within Pusan City, Korea, one of the third ranked centers within Pusan-the first ranked is CBD, the second is subCBD, the third are Spa Shopping district, Tongnae shopping district, Jobang-Ap shopping district and Yangjeong shopping district. This paper serves as a part of series studies which attempt to clarify the internal structure of Pusan as a whole. Part(I) of this study deals with the pattern of functions including information & culture, business, recreation and retailing. The results are as follows. 1. Pusan Station is one of higher ranked class of central places within Pusan City. But the ratio of dwelling houses is the highest in Pusan Station among the 9 higher ranked central places within Pusan. It means that the residential areas still remain along the maze type of narrower streets inner part of the blocks, especially western belt of this shopping district. 2. Business functions are one of the important criteria which classified the central places within the city and Pusan Station is the first ranked shopping districts in terms of these criteria among the 9 higher ranked central places including CBD within Pusan City. It suggests that Pusan Station is the miniature of the CBD, SubCBD is not the miniature of CBD in the view point of business function. It also means that Pusan Station Shopping District has been developed as a special shopping district or as a special central place. It has not been evolved as a center of the hierarchy of central places within the city by the natural or organic growth. 3. Pusan Station as 'the third space or drinking place' and it's characteristics as a amusement center presents at so called the 'Texas Town'-free tax area- whose customers are mainly U. S. soldiers and foreign sailors. But from the 1990s, this 'Town' changed to 'Russian Town', You can easy to meet many Russians and Russian lettered signboards-not English- along the street. 4. Convenient stores distribute mainly at back streets or along the narrower streets. It means that this kinds of stores have a residential oriented character. And a certain convenient stores locate with almost same distances. It suggests that it's hinterland is limited in nearer neighborhoods.

• Sijohaknonchong
• /
• v.30
• /
• pp.263-300
• /
• 2009

Adoration for nature constitutes one of the primary subjects that literature has tackled since the origin of human history. Nature expressed through a poet's subjective imagination is the internalized and reorganized nature. This study examines the view on nature enacted in Ch'o-Jung's three-verse poems (sijo) in light of the traditional views on nature implicated in the ancient three-verse poems (koshijo), which is in line with the long-established Oriental view on nature. To dignitaris(sadaebu) in the Chosun Dynasty, nature appeared as the idealistic subject for moral culture ($shims{\breve{o}}ngsuyang$), which also becomes the literary space where the purity and justice of the world view of Neo-Confucianism(Sungrihak) is contained in the form of the three-verse poem, the lyrical poetic space where the "I" is united with nature by way of "enjoying of wind and moon"($umpungnongw{\breve{o}}i$) and "living in quiet retiremen"($yuyuchaj{\breve{o}}k$), and the object for the poetical perception of the surrounding world. Ch'o-Jung' s three-verse odes are found in Reed pipe ($Ch'oj{\breve{o}}k$), Sixty Five Pieces of Three-Verse Odes (Samhaengshi-$yukshipopy{\breve{o}}n$), Autumn Fragrance ($Hyangginam{\check{u}}n-ga{\check{u}}l$), and The Words of Zelko va Tree ($N{\check{u}}tinamu{\check{u}}i-mal$). This study analyzes 212 pieces of Ch'o-Jung' s three-verse poems chosen from theses books. In Ch'o-Jung's poems, the traditional view on nature expressed in the ancient three-verse poems is rendered in such a way that metaphysical understanding of nature is indirectly transmitted through the objective correlatives found nature. Nature is no longer the object of straightforward utterance, but transformed, displaced, and removed: that way, nature gets objectified to form a complicated and multi-layered structure. In conclusion, the view on nature manifested in Ch'o-Jung's three-verse poems is based on traditional metaphysics. Second, nature is the object of lyrical nostalgia and adoration. Third, nature is imbued with the fundamental affection for parents. Fourth, nature is associated with organic life. Fifth, the nature in Ch'o-Jung's poems reveals the beauty of stillness endorsed in Lao-tse's and Chung-tze's philosophy. And last, nature is the agent for self-realization and meditation.