폴리에테르설폰(PES)과 폴리페닐렌설파이드설폰(PPSS)을 블렌딩한 고분자를 이용하여 음이온교환막을 제작하였다. EDXS와 FT-IR 분석으로부터 제작한 음이온교환막이 음이온교환기인 -N-을 갖는다는 것을 확인하였다. 1 mol/L의 황산 용액에서 이온전도도를 측정하였다. 제작한 음이온교환막은 0.015~0.083 S/cm의 이온전도도를 가졌으며, 시판의 음이온교환막인 AFN과 APS의 값과 비교하여 동등 이상의 값을 가졌다. 제작한 음이온교환막의 바나듐 레독스 흐름 전지용 격막으로 사용한지를 평가하기 위해 각 바나듐 이온의 투과를 측정하였다. 제작한 음이온교환막의 각 바나듐 이온의 투과도는 시판의 양이온교환막인 Nafion 117과 시판의 음이온교환막인 AFN과 비교하여 낮은 값을 가졌다.

The fumigation toxicity of carbonyl sulfide to T. castaneum as a storage grain pest was evaluated. Carbonyl sulfide (COS) is registered in Australia for microorganism present in soil, root and fertilizer. the fumigation activity of carbonyl sulfide was investigated in 12 L desiccator for 24 h exposure to eggs, larvae, pupae, adults of T. castaneum. Eggs and pupae were showed 87.3% and 95.6% mortality for 25 mg/L of COS, respectively. Larvae and adults were investigated with 80.0% and 100.0% mortality at 15 mg/L treatment, respectively. Therefore, the eggs of T. castaneum showed the highest tolerance to COS.

Carbonyl sulfide(COS) is a naturally generated gas from fermentation process of microbes and from plant root and stem. COS was firstly registered as a fumigant at 1993 to control stored product pests. To supplement environmental problems and toxicity of commercial fumigants and develop new fumigant, we have processed the susceptibility assessment of carbonyl sulfide on important agricultural pests, Myzus persicae and Tetranychus urticae. Every growth stages of two insect species were tested, and five dosages of carbonyl sulfide were treated for 4 hours, and the mortality was investigated after 24 hours of treatment. Nymphal stage of M. persicae was completely controlled at more than 20 mg/L dosage, and adult stage showed 95.8% mortality at 80 mg/L dosage. The LC50 of M. persicae was 7.314mg/L for nymph and 26.117mg/L for adult stage. Egg stage of T. urticae showed 91.2% mortality when treated with 100mg/L carbonyl sulfide, and nymph and adult stage showed 100% and 94.1% mortality at 8mg/L and 80mg/L, respectively. The LC50 of T. urticae was 73.110mg/L for egg, 2.818mg/L for nymph and 12.054mg/L for adult stage.

A lab-scale biofilter with fungal growth has been studied to investigate the removal of gas-phase hydrogen sulfide. The biofilter inoculated initially with the aerobic activated sludge was operated for 100 days under acidic condition, and 0.36 L/d of the buffered nutrient with 0.05 g/L Chloramphenicol and Gentamicin was injected into the biofilter. The critical removal capacity of hydrogen sulfide was up to 22 g/m³/h. The pH of the effluent liquid was stable at pH 1.5-2, corresponding to the volatile suspended solids of 20-50 mg/L. In microbial analysis through the plate count method, it was found that fungi were dominant over bacteria. The fungi isolated from biomass in the bilfilter were identified as Acidomyces acidophilus and Aspergillus fumigatus. Sulfate and thiosulfate were also detected in liquid samples, as a result of the biological sulfur oxidation in the biofilter bed. For the analysis of sulfur mass balance, the accumulated mass of sulfate and thiosulfate reached up to 67.5% of inlet sulfur. Sulfur was also detected on the biomass collected from the biofilter through Scanning electron microscopy/Energy dispersive X-ray spectroscopy.

Acidic and basic mixtures of odorous compounds are commonly emitted from various sources, and, in an absorption process, pH conditions in the liquid phase significantly affect the performance. In this study, the effect of pH on mass transfer in a bubble column reactor was evaluated using hydrogen sulfide and ammonia as a model mixture. Their mass transfer coefficients were then calculated. Furthermore, the total mass transfer coefficients as a function of pH were evaluated, and the experimental data were fitted into an empirical equation using dimensionless numbers. The mass transfer rates of hydrogen sulfide, the non-ionic form, increased dramatically with increasing pHs, while those of ammonia were almost unchanged because of its high solubility. As a result, a favorable pH condition for less soluble compounds must be selected to achieve high absorption capacity. The total mass transfer rates, which took into account pH effects as well as all the non-ionic and ionic constituents together, were found to be from 2.2 to 2.4 × 10−3 min−1 for hydrogen sulfide and ammonia, respectively, and they were almost constant at different pHs. The empirical equations, which were derived to obtain the best fit for the total mass transfer rates, implied that a method to increase diffusivity of each compound should be applied to improve overall mass transfer. In addition, when using the empirical equation, a mass transfer coefficient at a given set of pH and operating conditions can be calculated and used to design a water scrubbing process.

Carbonyl sulfide is a chemical that is registered as a crop protection product in Australia due to microorganisms such as soil, plant roots, branches, fertilizers and compost. In order to develop new fumigants for domestic use, the susceptibility of Carbonyl sulfide fumigants to two agricultural pests was evaluated. The susceptibility of peach aphid and spotted mite, which is an agricultural pest, was evaluated. After 5 hours of treatment (10, 20, 40, 60, and 80 mg / L) . As a result, peach aphid larvae showed a high mortality rate of 97.6% at 10 mg / L and 100% at 20 mg / L or more. Larvae were found to have a rate of 95.8% at 80 mg / L. The insect mortality rate was 91.8% at 60 mg / L and 94.1% at 80 mg / L.

강직한 아로마틱 기능기를 주쇄로 갖는 폴리아로마틱 고분자는 일반적으로 해당 단량체의 축합반응을 제조된다. 많은 유형의 폴리아로마틱 고분자 중에서 폴리(파라-페닐렌)과 폴리(페닐렌 술파이드)는 그 고분자 구조의 특성으로 내열성이 우수하고 기계적 특성과 내화학성이 뛰어난 고성능 열가소성 수지의 대표적인 예이다. 특히 폴리(페닐 렌 술파이드)는 전도성 고분자, 전자부품 엔캡슐레이트, 인쇄회로기판, 광섬유, 나노복합체 등 현대산업 기술에서는 없어서는 안될 중요한 소재로 자리 잡았다. 본고에서는 대표적인 폴리(아로마틱) 고분자인 폴리(파라-페닐렌)과 폴리(페 닐렌 술파이드)의 합성과 그 응용에 관한 그동안의 연구동향을 간단히 살펴보았다.

Hydrogen sulfide (H2S) emitted from various sources is a major odorous compound, and non-thermal plasma (NP) has emerged as a promising technique to eliminate H2S. This study was conducted to investigate lab-scale and pilot-scale NP reactors using corona discharge for the removal of H2S, and the effects of relative humidity, applied electrical power on reactor performance and ozone generation were determined. A gas stream containing H2S was injected to the lab-scale NP reactor, and the changes in H2S and ozone concentration were monitored. In the pilotscale NP experiment, the inlet concentration and flow rate were modified to determine the effect of relative humidity and applied power on the NP performance. In the lab-scale NP experiments, H2S removal was found to be the 1st-order reaction in the presence of ozone. On the other hand, when plasma reaction and ozone generation were initiated after H2S was introduced, the H2S oxidation followed the 0th-order kinetics. The ratio of indirect oxidation by ozone to the overall H2S removal was evaluated using two different experimental findings, indicating that approximately 70% of the overall H2S elimination was accounted for by the indirect oxidation. The pilotscale NP experiments showed that H2S introduced to the reactor was completely removed at low flow rates, and approximately 90% of H2S was eliminated at the gas flow rate of 15 m3/min. Furthermore, the elimination capacity of the pilot-scale NP was 3.4 g/m3·min for the removal of H2S at various inlet concentrations. Finally, the experimental results obtained from both the lab-scale and the pilot-scale reactor operations indicated that the H2S mass removal was proportional to the applied electrical power, and average H2S masses removed per unit electrical power were calculated to be 358 and 348 mg-H2S/kW in the lab-scale and the pilot-scale reactors, respectively. To optimize energy efficiency and prevent the generation of excessive ozone, an appropriate operating time of the NP reactor must be determined.

Zinc Sulfide (ZnS) is one of the II-VI semiconducting materials, having novel fundamental properties and diverse areas of application such as light-emitting diodes (LEDs), electroluminescence, flat panel displays, infrared windows, catalyst, chemical sensors, biosensors, lasers and biodevices, etc. However, despite the remarkable versatility and prospective potential of ZnS, research and development (R&D) into its applications has not been performed in much detail relative to research into other inorganic semiconductors. In this study, based on global patent information, we analyzed recent technical trends and the current status of R&D into ZnS applications. Furthermore, we provided new technical insight into ZnS applicable fields using in-depth analysis. Especially, this report suggests that ZnS, due to its infrared-transmitting optical property, is a promising material in astronomy and military fields for lenses of infrared systems. The patent information analysis in this report will be utilized in the process of identifying the current positioning of technology and the direction of future R&D.

This study has implemented an experiment in which hydrogen sulfide was removed by establishing a two-stage packed tower effector filled with nutritious medium and also filling a tower that was immobilized in ceramic media after isolating and identifying the sulfur oxidizing bacteria from a sewage treatment plant. As a result, strains isolated from the sewage treatment plant were found to be similar, including Bacillus fusiformis, Bacillus anthracis sp., Paenibacillus sp., Serratia marcescens sp., Bacillus thuringiensis. The effector that immobilized isolated strains in the ceramic media achieved an approximately 90% removal rate of hydrogen sulfide, while the sterilized ceramic media not immobilized with isolated strains showed a removal rate of about 65%. In addition, the removal rate of hydrogen sulfide in the primary media packing effector immobilized with sulfur oxidizing bacteria was about 92%, while the secondary effector filled with medium had a hydrogen sulfide removal rate near 100%. In addition, 90% efficiency of removal was shown in conditions of EBCT 60s in the experiment that investigated removal rate of hydrogen sulfide according to residence-time, while the efficiency was rapidly reduced up to 45% in conditions of EBCT 30s. On the other hand, when operating for an extended period time while increasing the concentration of injected hydrogen sulfide, the amount of sulfate was increased from 2 mg/L to 12.7 mg/L, and pH was rapidly reduced to 2.7.

This study has implemented an experiment in which hydrogen sulfide was removed by establishing a two-stage packed tower effector filled with nutritious medium and also filling a tower that was immobilized in ceramic media after isolating and identifying the sulfur oxidizing bacteria from a sewage treatment plant. As a result, strains isolated from the sewage treatment plant were found to be similar, including Bacillus fusiformis, Bacillus anthracis sp., Paenibacillus sp., Serratia marcescens sp., Bacillus thuringiensis. The effector that immobilized isolated strains in the ceramic media achieved an approximately 90% removal rate of hydrogen sulfide, while the sterilized ceramic media not immobilized with isolated strains showed a removal rate of about 65%. In addition, the removal rate of hydrogen sulfide in the primary media packing effector immobilized with sulfur oxidizing bacteria was about 92%, while the secondary effector filled with medium had a hydrogen sulfide removal rate near 100%. In addition, 90% efficiency of removal was shown in conditions of EBCT 60s in the experiment that investigated removal rate of hydrogen sulfide according to residence-time, while the efficiency was rapidly reduced up to 45% in conditions of EBCT 30s. On the other hand, when operating for an extended period time while increasing the concentration of injected hydrogen sulfide, the amount of sulfate was increased from 2 mg/L to 12.7 mg/L, and pH was rapidly reduced to 2.7.

Odor compounds and air-born microorganisms are simultaneously emitted from various aeration processes such as aerobic digestion, food-waste compositing, and carcass decomposition facilities that are biologically-treating wastes with high organic contents. The air streams emitted from these processes commonly contain sulfur-containing odorous compounds such as hydrogen sulfide(H2S) and bacterial bioaerosols. In this study, a wet-plasma method was applied to remove these air-born pollutants and to minimize safety issues. In addition, the effects of a gas retention time and a liquid-gas ratio were evaluated on removal efficiencies in the wet-plasma system. At the gas reaction time of 1.8 seconds and the liquid-gas ratio of 0.05 mLaq/Lg, the removal efficiency of bioaerosol was approximately 75 %, while the removal efficiency of H2S was lower than 20 %, indicating that the gaseous compound was not effectively oxidized by the plasma reaction at the low liquid addition. When the liquid-gas ratio was increased to 0.25 mLaq/Lg, the removal efficiencies of both H2S and bioaerosol increased to greater than 99 %. At the higher liquid-gas ratio, more ozone was generated by the wet-plasma reaction. The ozone generation was significantly affected by the input electrical energy, and it needed to be removed before discharged from the process.

The contents of this paper is to develop a passive sampler for H2S measurement. When the H2S gas exists in the air, AgNO3 solution coated filter of white used phenomenon which is exchanged with black. If the H2S gas concentration increased, the color of AgNO3 solution coated filter is discolored more black. H2S passive sampler measures the H2S gas concentration by changed color of AgNO3 solution coated filter. The reproducibility of the H2S passive sampler is very stable to within an error 5%RSD. The black color of AgNO3 solution coated filter showed a linear relationship with the H2S gas concentrations. In addition, correlation of the developed CDM and CR-10(Minolta, Japan) showed a high correlation to 0.99. Manufactured H2S passive sampler must be kept refrigerated, stability and reactivity was observed for up to 20 days

Wastewater containing heavy metals such as copper (Cu) and nickel (Ni) is harmful to humans and the environment due to its high toxicity. Crystallization in a fluidized bed reactor (FBR) has recently received significant attention for heavy metal removal and recovery. It is necessary to find optimum reaction conditions to enhance crystallization efficacy. In this study, the effects of crystallization reagent and pH were investigated to maximize crystallization efficacy of Cu-S and Ni-S in a FBR. CaS and Na2S·9H2O were used as crystallization reagent, and pH were varied in the range of 1 to 7. Additionally, each optimum crystallization condition for Cu and Ni were sequentially employed in two FBRs for their selective removal from the mixture of Cu and Ni. As major results, the crystallization of Cu was most effective in the range of pH 1-2 for both CaS and Na2S·9H2O reagents. At pH 1, Cu was completely removed within five minutes. Ni showed a superior reactivity with S in Na2S·9H2O compared to that in CaS at pH 7. When applying each optimum crystallization condition sequentially, only Cu was firstly crystallized at pH 1 with CaS, and then, in the second FBR, the residual Ni was completely removed at pH 7 with Na2S·9H2O. Each crystal recovered from two different FBRs was mainly composed of CuxSy and NiS, respectively. Our results revealed that Cu and Ni can be selectively recovered as reusable resources from the mixture by controlling pH and choosing crystallization reagent accordingly.

Graphite oxide (GO) was produced using the modified Hummer's method. Poly(p-phenylene sulfide) (PPS)/reduced graphite oxide (RGO) composites were prepared by in situ polymerization method. The electrical conductivity of the PPS/RGO composites was no more than 82 S/m. It was found that as GO content increased in the PPS/RGO composites, the crystallization temperature and electrical conductivity of the composites increased and the percolation threshold value was at 5-8 wt% of GO content.

본 연구의 목적은 강제환기가 적용되는 슬러리 돈사를 대상으로 돼지 생육 단계별 돈방 유형 측면과 계절적 조건에 따른 암모니아와 황화수소의 실내 농도를 측정 분석하여 정량화하는 데 있다. 임신/분만 돈방의 경우 봄철은 5.60(±2.48) ppm과 178.4(±204.8) ppb, 여름철은 2.51(±3.08) ppm과 86.6(±112.5) ppb, 가을철은 4.96(±2.84) ppm과 182.3(±242.6) ppb, 겨울철은 6.82(±3.42) ppm과 206.3(±356.8) ppb로, 자돈방의 경우 봄철은 7.18(±3.26) ppm과 486.0(±190.2) ppb, 여름철은 4.23(±2.95) ppm과 206.4(±186.9) ppb, 가을철은 7.02(±2.65) ppm과 465.4(±156.8) ppb, 겨울철 은 9.25(±3.68) ppm과 618.4(±298.3) ppb로, 육성/비육 돈방의 경우 봄철은 9.26(±3.02) ppm과 604.4(±186.8) ppb, 여름철은 6.78(±3.88) ppm과 312.5(±215.4) ppb, 가을철은 9.34(±2.14) ppm과 578.2(±248.1) ppb, 겨울철은 14.65(±3.15) ppm과 825.3(±316.9) ppb로 분석되었다. 측정 결과 암모니아와 황화수소 모두 돼지 생육 단계별 돈사 유형 측면에서는 육성/비육 돈사>자돈사>임신/분만 돈사의 순서로 나타났고(p<0.05), 계절적 측면에서는 겨울>봄>가을>여름 순서로 조사되었으나 봄철과 가을철 데이터 간의 차이는 통계적으로 입증되지 않았다(p>0.05).