• Journal of the Korean GEO-environmental Society
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• v.9 no.2
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• pp.15-22
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• 2008

Recently loess are used as design and construction materials in some construction sites. However, many problems have come to the fore because the loess was considered merely as ordinary soil, not taking the engineering characteristics of loess into account at all. The purpose of this study is to effectively mix and use the oyster shell-which is the byproduct of oyster farming in the clean and pure water zone of Southwestern region-with loess in a bid to increase the utility, considering that loess itself has the limit for civil engineering purpose, and research the usability of oyster shell as an alternative material for construction.

• Journal of Korean Society of Environmental Engineers
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• v.33 no.7
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• pp.530-535
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• 2011

In this work, the adsorption characteristic of the composites by adding loess with aluminum ("Al-loess") and Loess with lanthanum ("La-loess") which have been developed to effectively remove phosphorus, the substance which causes the eutrophic lake has been evaluated. According to the result of the work, as the amount of aluminum or lanthanum put in 1g of loess increases, the combined amount also increases accordingly. When the loess with no aluminum or lanthanum attached was used, the rate of removing phosphorus was different in comparison with the case of using the composites of 0.5, 1 and 2 mg of aluminum and 0.5, 1 and 3 mg of lanthanum in each gram of loess. It was observed the amount required to remove 1 mg $PO_4^{3-}$-P/L of phosphorus completely is approximately 2 to 10 times less for the composite of Al-loess than loess alone. Also, in case of the composite of La-loess, the amount was decreased by about 1.5 to 10 times. In order to observe the rate of adsorption phosphorus with Al-loess and La-loess, the composites were used for the observation up to three times by water washing. As a result, the water washing of the composite did not affect phosphorus removal. According to the effect of pH, there is a high rate of removing phosphorus in the pH range of 5~8. It seems that the developed composite will effectively remove phosphorus when it is spread in the natural water system. Also, since Al-loess and La-loess composites are rapidly precipitated within 30 minutes, it is stabilized quickly at the bottom of the eutrophic lake and becomes responsible for the removal of phosphorus in water and eluted from the water and the sedimentary layer.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.36 no.6
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• pp.716-722
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• 2003

This study determined the optimum dosage for coagulation reactions of red tide organisms (RTO) using a combination of ignited oyster shell powder (10sp) and loess and examined the electrokinetic and rheological characteristics of their flocs. Two kinds of RTO, Cylindrotheca closterium and Skeletonema costatum, were sampled in Masan Bay and cultured in the laboratory. Coagulation experiments were conducted using various concentrations of IOSP, loess, IOSP+1oess, RTO, and a jar tester RTO cell numbers were counted for both the supernatant and RTO culture solution. The removal rates increased rapidly with increasing IOSP concentrations up to 50 mg/L and loess concentrations up to 800 mg/L. A removal rate of $100\%$ was reached at 400 mg/L of IOSP and 6,400 mg/L of loess. The highest increment $(16.7\%)$ of the rates of coagulation reaction occurred using both IOSP and loess (50+200 mg/L) in comparison with IOSP alone. The rate of coagulation reaction using both IOSP and loess (50+200 mg/L), $90.6\%,$ was similar to employing either IOSP of 150 mg/L or loess of 3,200 mg/L. All of the coagulation liquids for RTO, IOSP (200 mg/L), loess (200 ma/L), and IOSP+1oess (200+200 mg/L) revealed non-Newtonian fluid properties and therefore their shear rate vs. shear stress curves were non-linear. The coagulation liquids revealed elastic body properties at a lower shear rate increasing in the following order: RTO, IOSP (200 mg/L), loess (200 mg/L), and IOSP+1oess (200+200 mg/L. IOSP+1oess (200+200 mg/L) especially demonstrated plastic flow properties at a lower shear rate.

• Biomedical Science Letters
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• v.10 no.2
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• pp.129-135
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• 2004

The study was carried out through measuring the temperature and humidity of the indoor/outdoor space and the distribution of interior thermal condition, and investigating the effect of loess materials on human body. The purpose of this study is to analyze the change of dry bulb temperature and relative humidity and correlation of thermal reaction of human body with ASHRAE (American Society of Heating, Refrigerating and Air-conditioning) comfort chart in the loess interior space. In the view point of biomedical sciences, loess interior space provides optimum thermal conditions for human thermal sensation.

• Journal of Korean Society of Rural Planning
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• v.11 no.3 s.28
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• pp.53-57
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• 2005

Up to recently building are constructed focusing on the convenience of residential condition. However, environmental-friendly materials is required for construction as people are spending more time inside buildings and causes of many problems like sick-building syndrome are known due to the noxious gases and polluted air originated from construction materials. Although loess(hwangtoh) is an environmental-friendly material, it has limitations in compressive strength far a construction material. The purpose of this study is to suggest the optimal ratio of loess(hwangtoh) mortar by tests of compressive strength comparing with standard strength of floor finishing mortar and evaluate the usability of loess(hwangtoh) mortar for floor finishing material through an impact test, a cracking test and a abrasion test. Based on the results of this study, 86% of loess(hwangtoh) and 14% of inorganic binder is suggested for the optimal mixture ratio of loess(hwangtoh) mortar. Moreover, the characteristics of loess(hwangtoh) is suitable for floor finishing material in impact, crack, abrasion.

• Journal of Korean Society of Water and Wastewater
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• v.26 no.5
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• pp.713-721
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• 2012

In many instances phosphorus is a limiting factor for eutrophication in streams, and lakes. Because wastewater treatment plant itself may be the main phosphorus source in a natural water body, removal of phosphorus in final effluent of wastewater treatment processes is required. Amongst various technologies for phosphorus removal in wastewater, adsorption technology was investigated using activated Ca-loess complex. Ca was added in loess to enhance adsorption capacity and intensity of phosphorus. Ca added loess was activated at a high temperature of $400^{\circ}C$ which turned out to be the optimum temperature. Activated Ca-loess complex below $400^{\circ}C$ had not enough strength to be applied as an activated Ca-loess pallet column in wastewater treatment process. Ca-loess complex which activated above $400^{\circ}C$ lost its adsorption capacity as the loess surface was glassified when the activation temperature reached above $400^{\circ}C$20. Even if adsorption capacity of activated Ca-loess was not very high due to the lack of abundant pores on its surface, adsorption intensity was still high because it was activated with added Ca in loess. Activated loess was made by pallets. The activated loess pallets were filled in a column, and were applied in wastewater treatment process. Using an activated Ca-loess pallet column, total phosphorus (T-P) was reduced from about 0.5 mg/l to lower than 0.1 mg/l in wastewater treatment, and ionic phosphorus (phosphate) was completely removed for the four months of pilot plant operation.

• KIEAE Journal
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• v.9 no.6
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• pp.13-18
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• 2009

Korean traditional houses have been developed in harmony with natural environment and comfortable indoor condition by using the natural resources including building layout, space composition and materials. Originally Korea traditional architectures have used wood lintel constructions and loess walls through the many years. Theses loess have many strength such as highly heat capacity, controling of humidity, a deodorant than any other materials. Nowaday it is recommended to use exterior and interior walls in loess wall to meet the eco-friendly materials to improve our residental environmental. Thus this study aims to research the sound insulation performance of traditional loess brick wall varied with thickness, thermal insulation materials and cavity wall. The sound insulation performance of these loess walls are compared with other masonry wall's and sound insulation performance of th walls were tested in anechoic laboratory to measure the sound transmission loss of these walls. The loess brick wall with 75mm thickness of cavity is shown the sound insulation performance with Rw 57 which is nearly same performances of 1B brick wall and cement 8' block wall, The improving effect of insulation materials is shown in the high frequency bandwidth. Especially, there is improving as much as 11 dB using the extruded poly stylene form(75mm) and poly ethylene film(0.7mm).

• Journal of the Korean Society of Clothing and Textiles
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• v.24 no.5
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• pp.619-627
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• 2000

Historically, dyed textiles were symbols of status and, because of their expense, reserved only for people of wealth and specalist, Early dye sources probably included plant, animal and mineral extracts. As synthetic dyes have been developed, beginning with synthetic indigo in 1897, reliance on natural dye sources diminished. But renewed interest in natural dyes is fueled by a pro-environment consumer aware of the ecological liabilities of the dye industry. Han Jee was imported from China where it was influenced to period of the three kingdoms(Silla, Baekje, Kokuryo). After that, Han Jee was used for paper in old Korea for long thime before paper was came with civilization. In this paper, dyeing of Han Jee with loess were investigated according to dyeing temperature, dyeing time, loess concentration, and effects of additives. As a reuslts, λmax of Han Jee dyed by loess was 710nm. ΔE values of Han Jee increased by loess concentration, dyeing time, dyeing temperature. Dyeing with additives treatment increased dyeability. Especially, Han Jee treated with aluminium acetate shows the largest dyeability of the Han Jee. The Han Jee dyed loess had very good lightfastness.

• Proceedings of the Korean Fiber Society Conference
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• 2003.10b
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• pp.229-230
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• 2003

In these days, it is actively investigated to use loess in textile industry. The loess have been reported for emissivity of far-infrared and negative ion, and antibacterial efficacy. The loess consist of quartz, feldspar, clay mineral, iron oxide mineral, gibbsite [Al(OH)$_3$], etc. The main component of loess is clay minerals which have great adsorption about ion exchange and far-infrared emission properties. Recently, various inner-wears, sheets, and interior goods are manufactured using the loess due to its improved blood circulation, metabolism, antibacterial and deodorizing properties. (omitted)

• Journal of the Korean Society of Clothing and Textiles
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• v.21 no.3
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• pp.600-606
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• 1997

The dyeing with loess has been studied. Two kinds of cotton fabrics having different thickness and density were dyed in loess paste bath. The color differences of the fabrics which were dyed repeatedly.five times were not significant. The dyeing of cotton fabrics with loess was not exactly reproducible, but dyeability of the cotton fabrics of high density was better than that of low density. Loess on the dye6 fabrics was physically jammed between the fibers in the form of the fine particles. The cotton fabrics dyed with loess have good light fastness, but their laundering fastness and abrasion fastness were not good. An aftertreatment was carried out by using the extracted solution from acorn or persimon, and FeSO4 lot improving fastness. When the dyed fabrics was after-treated with FeSO4, the laundering fastness and wet abrasion fastness were improved extremely.