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This study aimed to calculate the habitable time using a fire and evacuation simulation program for an in-operation nursing hospital, compare and analyze it with the required evacuation time, and suggest a plan to enhance evacuation safety. The habitable time was calculated through fire simulations by assuming that a fire was caused by the careless handling of heating appliances in a doctor’s office. The evacuation time required for the occupants of the nursing hospital, including those who could not evacuate themselves, was compared and analyzed with the habitable time through the evacuation simulation. In the simulation, nursing hospitals of two stories or higher were not mandated to install ramps or elevators, per the current standards. The evacuation time of the nursing hospital subjected to this experiment exceeded the habitable time; hence, evacuation safety was not ensured. Through evacuation time analysis, we sequentially compared and analyzed the cases where those who were unable to evacuate on their own would evacuate using only the ramp, or only the elevator, or both, the ramp and the elevator. Additionally, the cases in which additional evacuation spaces were installed were also analyzed for the three situations. The evacuation simulation results demonstrated that the evacuation time significantly increased in other instances compared with the cases where ramps, elevators, and evacuation spaces were all installed. The results indicate that all nursing hospitals that are two stories or higher should be required to install all ramps, elevators, and evacuation spaces by amending related laws.

This study aims to measure changes in the evacuation time with respect to the desk spacing used by internet computer gaming facility providers using an evacuation simulation program and to analyze the results. Currently, the “Special Act on the Safety Management of Multi-Use Businesses” only regulates the width of the internal evacuation passage. There is no regulation on the width of the evacuation space as determined by the arrangement of furniture in internet computer gaming facilities. Considering this, the evacuation times for evacuation passage widths of 190, 210, 230, and 260 cm were compared and analyzed considering various variables of the facility space. The results show that there is a large difference in the evacuation time, ranging from 166.0 s to 154.0 s, as the passage width increases from the minimum to the maximum. With the increasing popularity of internet gaming facilities and considering the safety of the evacuees, it is necessary to draft regulations on the width of new evacuation spaces during the deployment of internet computer gaming facilities.

This study allows comparative analysis of the evacuation time required for nursing hospitals using an evacuation simulation program and proposes an optimized procedure to enhance safety. Considering the current laws and regulations that nursing hospitals may be exempted from using ramps or elevators, this study analyzed the evacuation time of all occupants, including patients who cannot evacuate by themselves. The following three cases were analyzed in order: elevators were exempt but ramps were installed, ramps were exempt but elevators that can move a bed were installed, and both elevators and ramps were installed. Last, the study comparatively analyzed the evacuation time for the above-mentioned cases when an additional evacuation space was installed. The results of the evacuation simulation showed that the required evacuation time was the shortest when a ramp, an elevator, and an evacuation space were all installed. Although there are provisions exempting ramps or elevators in nursing hospitals, the law should be revised to require the installation of both of them in nursing hospitals of two floors or higher. It is also an appropriate time to discuss the retroactive enforcement of evacuation space—which replaces the vertical evacuation of those vulnerable during evacuation—currently required for newly built or change-of-use nursing hospitals.

In this study, to improve the characteristic that the waste gypsum reacts at the high temperature and high pressure when it is recycled, it was intended to develop the waste recycling method under the condition of room temperature and normal pressure. To do that, the calcium ion extraction test, and the mineralogical analysis and the structural analysis of the precipitation by the microbially induced calcite precipitation (MICP) were performed. The optimal calcium ion extraction condition was analyzed as solid-liquid ratio of 1:10, solvent type: HCl and HNO3. In addition, the air injection increased the activation of microorganism increasing the reduction of calcium ion by reaction time. Particularly, the precipitation was generated after MICP and it was confirmed that the precipitation was the calcium carbonate (CaCO3) through the mineralogical analysis and the structural analysis of the precipitation. Therefore, MICP can be utilized as a method to recycle the waste gypsum.

Since sewage sludge has a high moisture content even after dehydration, when used as energy such as fuel, the moisture content of sewage sludge must be reduced to 10% or less. In the case of using sewage sludge as fuel or reducing moisture, a fermentation and drying system by Bio-drying is introduced, and the Bio-drying system is generally dried by heat generated when aerobic microorganisms decompose organic matter in the sewage sludge, and the correlation between the temperature change and the water reduction of the fermentation tank is determined to be very important. The reduction of sewage sludge moisture by the bio-drying system was found to be most affected by the number of stirrings in the fermentation tank and the maintenance of high temperatures of 70oC or higher, and the reduction of temperature caused by excessive supply of air at 390 to 600mL/kg/min was found. In the case of experiments with one to five times more stirring times, the moisture reduction effect was 14.5% and 15.5%, which showed much greater reduction rate than the average reduction rate of 12.7%.

Anion and mole-ratio effects on the formation of coordination polymers (1–3) of thiacalix[4]-bis-monothiacrown-5 (L) incorporating two types of sulfur donors (crown loop and rim) are reported. In the reaction with AgPF6, an anion-uncoordinated two dimensional (2-D) coordination polymer {[Ag2L3](PF6)2}n (1) adopting a honeycomb (hcb) topology was isolated as a mole-ratio independent product. In the reactions with AgCF3CO2, an anion-coordinated honeycomb type 2-D coordination polymer {[Ag2L3(CF3CO2)2]·6CHCl3·2H2O}n (2) and a square-grid type 2-D coordination polymer {[Ag4L3(CF3CO2)4]·0.5CHCl3·0.5CH3OH·0.5toluene}n (3) with an sql topology were obtained below 1.0 equiv. and above 1.3 equiv., respectively. All products demonstrate that the only sulfur donor in the crown loop acts as a versatile bridgehead for the exo-binding probably due to its stronger basicity than that of the sulfur bridge in the rim. The powder X-ray diffraction (PXRD) studies reveal that anion-exchange between 1 (PF6, hcb) and 3 (CF3CO2, sql) in the solid state is reversible.

Herein, alkali metal complexes of bis-o-xylyl-(17-crown-5) (L) with different binding modes are reported. When NaI was reacted with L, a disodium(I) complex of the type [Na2(L)(H2O)2]I2 (1) with a good fit mode was isolated, providing the crown unit as a base of the pentagonal pyramid and a water molecule at its apex. However, the use of KPF6 gave a one dimensional (1-D) coordination polymer of type [K2(L)(PF6)2]n (2), in which dipotassium(I) complex units with a perching mode are linked by two PF6− ions to form an infinite zigzag chain. A cesium(I) ion is large enough to bind two crown units from different ligands with a sandwich mode to give a 1-D sandwich polymer of the type {[Cs(L)]Cl}n (3) as a first example, which might be applied as a networking tool in crystal engineering.

Five soft metal complexes (1–5) of a 16-membered O2S3-macrocycle (L) with different topologies and coordination modes, including discrete to infinite forms, and endo-, exo-, and endo/exo-coordination, were prepared and structurally characterized. Both mercury(II) complexes, [Hg(L)(NO3)2] (1) and [Hg(L)(DMF)2](ClO4)2·DMF (2), with nitrate and perchlorate anions, respectively, show a typical endocyclic structure. Two nitrate ions in 1 occupy the coordination sites, while two DMF molecules participate to the coordination sphere in 2 remaining two perchlorate ions uncoordinated. It is found that the anion-exchange of 2 in the solid state induced the conversion to 1 which involves the rearrangement of the coordination sphere. In silver(I) complexations, nitrate afforded a cyclic dimer complex [Ag2(L)2(NO3)2] (3). While hexafluorophosphate gave a 1-D zigzag coordination polymer {[Ag(L)]PF6}n (4). Interestingly, triflate led to the isolation of a tetranuclear bis(macrocycle) complex, {[endoAg(L)(CF3SO3)]2[μ-exoAg2(CF3SO3)2]} (5), which are dominated by the coordination modes (endoAg and exoAg) of L toward two types of silver(I) centers. For instance, two endocyclic complex units, endoAg2(L)2(CF3SO3)2, are linked by exocyclic metallacycle, [μ-exoAg2(CF3SO3)2], to give a 4:2 (metal-to-ligand) stoichiometry. From the results, it is obviously clear that the role of anions mostly is responsible to such structural diversity based on the exo-coordination mode.

Heavy metals are naturally occurring trace elements present in the environment, including soil, water, and air. However, high heavy metal concentration contamination from waste is a serious environmental problem brought on by industrial activities. The research in this study evaluated different biomineralized CaCO3 forms from individual bacteria species in heavy-metal-contaminated soils and mine tailings. Scanning electron microscope (SEM) images of the crystals were used to characterize the precipitated CaCO3. Generally, urea-hydrolysis bacteria form minerals via a microbiologically induced calcite precipitation (MICP) process. These bacteria produce the urease enzyme, which leads to urea-hydrolysis. These bacteria were isolated from heavy-metal-contaminated soils and characterized for their potential utilization in the S/S process. Optimum conditions for indigenous bacterial growth were 30 °C and a pH range of 7–8; and growth patterns were further affected by the growth medium salinity. SEM and X-ray diffraction (XRD) analyses demonstrated that bioaccumulated heavy metal ions were deposited around the cell envelope as rhombohedral and sphere shaped crystalline carbonate minerals in optimum conditions. In this study, the authors hypothesize that the indigenous bacteria can effectively precipitate heavy metals in soil and mine tailing with the urea-hydrolysis enzyme, and play an important role in heavy metal stabilization.

The title compound, C51H48N2O7, was synthesized by the reaction of 25,27-(3,6,9-trioxaundecane-1,11-dioxy)-26,28-(3-phenyl)-3-azapentane-1,5-dioxy)calix[4]arene with tetracyanoethylene in dry DMF. The compound has a 1,3-alternate conformation with an oxo-crown-5 unit and an aza-crown-3 unit with a nitrogen atom connecting tricyanoethylenephenyl group as a chromophore. Pairs of benzene rings of the calixarene are facing one another. Three of the four oxygen atoms connected to a benzene have endo-conformations while the other is exo. The oxo-crown-5 system has a t–g–g–t conformation. The dichloromethane solvent molecule is linked to the main molecule by a C—H...Cl hydrogen bond. In the crystal, C—H...O, C—H...Cl hydrogen bonds and C—H...π(ring) interactions are observed.

Conversion of carbon dioxide (CO 2 ) into methane (CH 4 ) on copper (Cu) surfaces were investigated to understand the fundamental mechanism of CO 2 reduction, and to suggest a key factor for designing promising catalysts for CO 2 conversion into hydrocarbon fuels. The density functional theory calculations revealed the lowest-energy reaction pathways on Cu(1 0 0), Cu(1 1 0), and Cu(1 1 1) planes, and determined that the potential limiting step for CO 2 reduction lies between the reaction intermediates CO ∗ and CHO ∗ ( ∗ denotes the state adsorbed on the catalyst surface). The energy barrier to the potential limiting step is lowered in the following order: Cu(1 1 0) 2 reduction by designing a Cu thin film on a supporting material with larger lattice constant than Cu. To demonstrate this, we evaluated the energy barriers to the potential limiting step on a single Cu thin layer supported on both palladium (Pd) and silver (Ag), and confirmed that the Pd supporting material can enlarge the interatomic distance of the single Cu(1 1 1) layer by 8.7% and thereby lower the energy barrier from 0.97 to 0.63 eV.

Recently, soil has been recognized as a crucially important resource that even can change the quality of life. Also, recent studies have gradually mentioned the importance of assessing soil impact induced by development plans and projects. In this study, after detailed soil assessement items were selected from our national environmental policies and international agreements, they were tested for the long-term dam construction planning in order to ensure more suitable implementation of strategic environment assessment(SEA). We found that soil resources can be impacted by diverse factors such as soil erosion, soil organic matters, soil moving, soil biodiversity, and others. Such detailed factors are found to be overlapped with the pervious EIA factors. Accordingly, additional studies would be required for finding out more reasonable connection between assessment factors during any SEA progress.

Hydrothermal carbonization (HTC) is a carbonization method of thermochemical process at a relatively low temperature(180-250 o C). It is reacted by water containing raw material. In this study, it was selected for effective disposal method offood waste because food waste in Korea has large amount water. 5 kg, 10 kg, 15 kg of food waste were reacted for 6 hoursat 200 o C for selecting the optimum amount of raw material. Since the derived optimum amount, food waste was reactedfor 2 hours, 4 hours and 6 hours at 200 o C and 1.5 MPa. After carbonization, it was analyzed to evaluated the properties byultimate analysis, iodine adsorption, BET surface area and SEM. After analyzing the characteristics, it can be utilized as abasic data for applied. Key words : Hydrothermal carbonization, Biochar, Food waste 1. 서론 2012년 우리나라 음식물 폐기물은 발생량은 13,209 톤/일이며, 이는 전체 폐기물 발생량의 약 27%에 해당하는양으로 매년 증가하는 추세를 보인다(Ministry of Enviro-nment, 2012). 하지만 폐기물 관리법 시행규칙 개정으로인해 2005년부터 매립이 금지되고, 최근 런던 협약에 의해 유기성 폐기물의 해양 투기도 전면 금지됨에 따라 음식물 폐기물의 처리 대안이 시급하게 요구되고 있다. 현재 시행되고 있는 음식물 폐기물의 처리 방법에는 퇴비화,소각화, 사료화, 재활용 등이 있으나, 우리나라 음식물의경우 다량의 염분과 수분을 함유하고 있어 위의 방법을적용하기 어려움이 있어 재활용이 저조한 실정이다.일반적으로 음식물 폐기물과 같은 유기성 폐기물을 재활용 가능한 물질로 전환시키는 방법으로는 생화학적, 화학적, 열화학적 방법 등이 있으며, 이 중 열화학적 방법은크게 high temperature pyrolysis(고온열분해법)과 hydro-thermal carbonization(HTC, 열수가압탄화법)으로 나뉜다(Bae, 2011). HTC는 대상물질이 180-250

NOx emissions from diesel vehicles have been regarded as a main cause of high NO2 concentration in metropolitan area. Recent studies have shown that the on-road NOx emissions of diesel vehicles are quite higher than the emission limits specified with the pre-defined test method for emission certification. To reduce air pollutants effectively, the discrepancy of emissions in certification and real-driving conditions should be tackled. In this study, the real-driving emissions have been estimated with portable emission measurement system (PEMS). The results of this study have shown that the on-road NOx emissions from diesel vehicles have been decreased as the introduction of stricter emission regulation, EURO-6, but additional reduction should be still required and robust technologies should be applied to control NOx in real-driving conditions. RDE-LDV (Real Driving Emission Light Duty Vehicles) test method being developed in the European Union can represent excessive on-road NOx emissions of diesel vehicles as applied emission technologies and can be a solution to remove discrepant NOx emissions between certification and Korean real-driving conditions. Among the NOx reduction technologies for EURO-6 diesel vehicles, selective catalytic reduction (SCR) system has shown the better performance than lean NOx trap (LNT) system to control on-road NOx emissions. Implementing RDE-LDV will require vehicle manufacturers to adopt the more effective NOx reduction technology in real driving conditions.

Korean territories has formed about 70% of mountainous areas that have acidified serious level to average pH 4-5. There are a number of abandoned metal mines about 1,000 in Korea. However, mine tailings and waste rock included heavy metals are exposed to long-term environment without prevention facility or treatment system. Thus, ongoing management and monitoring of soil environment are required. Most of abandoned mine scattered in forest areas of slopes. Soil erosion due to continuous rainfall in the slopy areas can cause the secondary pollution by the influence eutrophication of water system and the productivity loss of the plant. Therefore, this study would like to estimate pH leaching rate by artificial rainfall using waste neutralization-agent in lysimeter. Moreover, the potentially of secondary pollution related to precipitation is figured out through the experiments, and the optimal planting methods would examinate after neutralizing treatment in soil. Experiments composed three kinds of lysimeter; lysimeter 1 had filled only acidic soil, lysimeter 2 had neutralized soil, and lysimeter 3 had planting plants after neutralized soil. In the results, lysimeter 2 showed the lowest pH leaching, and there is not specific relativity with pH leaching of the seasonal characteristics.

In this study, several factors which can have an effect on soil during strategic environmental assessment (SEA) are analyzed against a total of 86 administrative plans and development basic plans of the SEA. Other factors which could have influences on soil are also analyzed after examining contents and rules required for preparing the SEA statement. Then, we propose assessment factors on soils during the SEA procedure. We think that this study could give baseline data to set up assessment items, criteria, and techniques that are highly necessitated in preparation of the SEA statement in the near future.