• Korean Chemical Engineering Research
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• v.51 no.6
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• pp.661-665
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• 2013

Effect of organic acid on the preparation of indium-oxalate salt from indium scraps generated from ITO glass manufacturing process was studied. Effects of parameters, such as type and concentration of organic acids, pH of reactant, temperature, reaction time on indium-oxalate salt preparation were examined. The impurity removal efficiency was similar for both oxalic acid and citric acid, but citric acid did not make organic acid salt with indium. The optimum conditions were 1.5 M oxalic acid, pH 7, $80^{\circ}C$, and 6 hours. On the other hand, the recoveries increased with pH, but the purity decreased. The indium-oxalate salt purity prepared by two cycles was 99.995% (4N5). The indium-oxalate salt could be converted to indium oxide and indium metal by substitution reaction and calcination.

• Korean Institute of Interior Design Journal
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• v.19 no.3
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• pp.136-144
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• 2010

Since most domestic apartment, built in bearing wall system limiting variability of space, in spite of its good durability, cannot accept life style change and is being wasted, dumped scraps of which cause environmental pollution and waste of resources. As a response for this, researches on sustainable housing, that is, 'long-life housing' which has high durability, and variability responding life style change of the resident are in progress in and out of country. Therefore, this article aims, in suggesting the various status appearing on apartment and the interior plan responding the problem, to research on the house plan in the future which can be used continuously instead consuming type of apartment shortly used and discarded with understanding of long-life housing developed in foreign countries, and grasping the factors of application plan. Various reports from previous researches were comparatively analyzed and the studies on the characteristics, the real examples and the types of the surfaces were performed on the experimental model of long-life housing and similar residential surfaces to find the concept to be applied to Long-Life Housing and the introduction method of such concept. This article tries not only to prevent 'scarp and build', the serious cause of environmental pollution, but also to be basic materials for interior construction plan afterwards through 'long-life housing interior design plan' as the new conception which can accept life style and life cycle change.

• Korean Journal of Veterinary Service
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• v.34 no.1
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• pp.55-61
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• 2011

Dermatopathologic findings on cutaneous streptothricosis (bovine dermatophilosis) were conducted in Dinajpur of Bangladesh for one year. The animals were examined clinically at hospital during the physical visit of the affected animals and clinical manifestations and patients' history were recorded. The gross lesions were systematically examined, noted and categorized. An impression smear was made by the skin scraps, stained with Gram's stain and examined microscopically for the presence of causative bacteria. The suitable sizes of skins of 3 animals typically affected with dermatophilosis were collected surgically from the animals, and prepared for the histopathological study. The cardinal clinical features and gross lesions were characterized as paint-brush cutaneous surface with matted hairs, scab and crust formation, roughened coat; istopathologically as hyperkeratosis, parakeratosis, typical "palisading encrustations", extensive proliferation of coccoid shaped, bluish coloured bacteria (zoospores) in the cells of the outer rootsheath of the hair follicles, separation of keratinized layer from the epidermal epithelium, epidermal hyperplasia, densely cellular dermis with moderate destruction of glandular structures. Coccoid shaped gram positive organisms which form multidimensional arrangement were also observed by impression smear. The clinical signs, gross lesions, morphology of the organisms, staining properties, and histopathological features of the affected skin were diagnostic criteria for the bovine cutaneous streptothricosis.

• Applied Chemistry for Engineering
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• v.16 no.4
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• pp.556-562
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• 2005

This study was performed to evaluate effects of pH and heavy metals on soil pollution in 167 sites of Gangwon-do. The overall pH range of soils was 4.3~8.4 The average soil pollution of Cd was 0.089 mg/kg (0.000~3.493 mg/kg), Cu 3.093 mg/kg (0.078~60.263 mg/kg), Pb 4.74 mg/kg (0.01~38.08 mg/kg), Hg 0.054 mg/kg (0.002~1.050 mg/kg), and As 0.971 mg/kg (0.031~77.051 mg/kg), but $Cr^{6+}$ was not detected in these soils. The average concentration of heavy metals in these soils was acceptable under the preliminary standard of soil preservation acts in Korea.

• Resources Recycling
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• v.15 no.6 s.74
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• pp.41-47
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• 2006

A study for recovering of copper and lead from electronic scraps has been carried out using a combination of bioleaching and solvent extraction. It was found that the citric acid generated by Aspergillus niger could be an imporant leaching agent acting in the solubilization of copper, iron, lead and tin from the electronic scrap. Copper could be selectively extracted by 10% LIX84 from the leaching solution and it recoved 99.9% of metallic copper by electrowinning process. Tin and iron were extracted from the remaining solution by 10% Alamine336 and stripped by NaCl solution. Finally, tin could be recovered as a metallic precipitates from the mixed solution of tin and iron by cementation with iron powder.

• Resources Recycling
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• v.23 no.3
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• pp.61-70
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• 2014

Tin has been widely used to solder, tin plated steel, bronze alloy, sputtering target for transparent electrode and chemical additives. It has been widely reported to the recycling technologies for tin scraps because of the scarcity and economic efficiency of the reserve. This study was analyzed by using open/registered patents KR, US, CN, JP and EP related to recycling technologies for processing scrap, sludges, waste fluid for plating process and spent alloy containing tin in between 1970 and 2013. Patents were collected using key-words searching and filtered by filtering criteria. The trends of the patents were analyzed by year, country, appliant and technology.

• Resources Recycling
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• v.23 no.3
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• pp.51-60
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• 2014

In this study, the domestic supply & demand of the raw materials of 35 rare metals was analyzed categorized as four types - ores, metals, compounds and scraps. Foreign trade volumes of the raw materials of rare metals have been steadily increased, furthermore, recently trade growth rate highly exceeds GDP. The raw materials of rare metals - silicon, nickel, molybdenum, manganese, etc. - for steel industry were the most big part of the raw materials of rare metals trade, while the raw materials of rare metals for electronics industry were imported relatively small volumes less than $100 million. However systematic supply & demand management on the raw materials of rare metals for electronics industry is needed since recently growth rate per year has been remarkably high over 20%. Import volumes were about three times bigger than export scale, and most of the raw materials of rare metals were traded as a metal form.

• Resources Recycling
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• v.26 no.3
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• pp.17-25
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• 2017

Electric arc furnace steelmaking dust has various physicochemical properties as volatile components generated in the melting process of steel scraps in an electric arc furnace, which is captured in oxide form as fine powder by reacting with oxygen in the air. In order to efficiently recycle these electric arc furnace dust, a kinetic basic experiment and a pilot production test were carried out in parallel. As a result, it was found that the electric arc furnace dust contain a large amount of Cl and alkali components, thus it was expected that the compounds have a great adverse effect on the actual operation for the recycling. It was confirmed that the volatilization behavior was progressing actively at $1100^{\circ}C$ and the electric arc furnace dust was melted at $1250^{\circ}C$. These results are the same as a result of pilot test for the formation behavior of zinc oxide and reduced iron. These results should be useful as basic data for designing the recycling plant of the electric arc furnace dust and establishing the operating conditions.

• Resources Recycling
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• v.10 no.4
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• pp.48-57
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• 2001

The main consistent materials and main elements of the bottom ash in municipal solid waste incineration ash according to particle size were investigated and the environmental hazards were considered by investigating the content of dioxin and heavy metals in bottom ash and the concentration of heavy metals in its leachate. The main materials of bottom ash are glasses, ceramics, scraps of iron. As the particle size increases, their percentage weight also increases and their percentage weight was over 70% in 4 mesh~25 mm particle size fraction. The main elements of bottom ash are CaO, $SiO_2$, $Fe_2$$O_3$,$ A1_2$$O_3$and the content of CaO decreases and the content of $SiO_2$increases as particle size increases. The heavy metals accumulate in small particle size fraction. The concentration of heavy metals in each leachate by domestic leaching test is almost similar. As the aging period is prolonged, pH of bottom ash lowers gradually and the leached concentration of Cu and Pb diminishes.

• Resources Recycling
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• v.23 no.4
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• pp.58-68
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• 2014

The statistics showed that about 1 billion automobiles were registered and about 40million ELVs occurred on the world in 2010. So all advanced countries including EU had plan to increase the ELVs recycling rate up to 95% of total by 2015. The Korean government also established a target for raising up to 95% of ELVs recycling rate according to 'Act on the Resource Circulation of Electrical and Electronic Equipment and Vehicles'. Before being satisfied with the requirement of recycling of ELVs however, the problem is issued on the scraps of plastic and non-ferrous metals which are now being abandoned and reclaimed with no adequate reuse. Therefore, as a part of preceding investigation on the present state of ELVs recycling in the world, this preliminary investigation study was carried out focusing on the state of EU's disposal and management regulations of ELVs and SLF/ASR including the world trend of disposal and management regulations of ELVs and SLF/ASR.