• The Journal of Korean Academy of Prosthodontics
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• v.36 no.5
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• pp.701-720
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• 1998

Research advances in dental implantology have led to the development of several different types of materials and it is anticipated that continued research will lead to advanced dental implant materials. Currently used pure titanium has relatively low hardness and strength which may limit its ability to resist functional loads as a dental implant. Ti-6Al-4V also has potential problems such as corrosion resistance. osseointegration properties and neurologic disorder due to aluminium and vanadium, known as highly toxic elements, contained in Ti-6Al-4V. Newly developed titanium based alloys(Ti-20Zr-3Nb-3Ta-0.2Pd-1In, Ti-20Zr-3Nb-3Ta-0.2Pd) which do not contain toxic metallic components were designed by the Korea Institute of Science and Technology (KIST) with alloy design techniques using Zr, Nb, Ta, Pd, and In which are known as non-toxic elements. Biocompatibility and osseointegration properties of these newly designed alloys were evaluated after implantation in rabbit femur for 3 months. The conclusions were as follows : 1. Mechanical properties of the new designed Ti based alloys(Ti-20Zr-3Nb-3Ta-0.2Pd-1In, Ti-20Zr-3Nb-3Ta-0.2Pd) demonstrated close hardness and tensile strength values to Ti-6Al-4V. 2. New desinged experimental alloys showed stable corrosion resistance similar to the pure Ti but better than Ti-6Al-4V. However, the corrosion rate was higher for the new alloys. 3. Cell culture test showed that the new alloys have similar cell response compared with pure Ti and Ti-6Al-4V with no cell adverse reaction. 4. New designed alloys showed similar bone-metal contact ratio and osseointegration properties compared to pure Ti and Ti-6Al-4V after 3 months implantation in rabbit femur. 5. Four different surface treatments of the metals did not show any statistical difference of the cell growth and bone-metal contact ratio.

• Journal of Society of Preventive Korean Medicine
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• v.6 no.1
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• pp.117-128
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• 2002

Metal problems in herbal medicine are not regulate properly by law and public management around world country until this time. General people belief as safety about herbal since natural material. And almost all persons can also purchase by their-self and use by self-prescription in reality. As this result herbal medicines can always occur acute and chronic toxicity by not proper use problems, side-effect and overdose. Heavy metal toxic diseases in historical view point was big accidents that didnot forget including minamata and itai-itai in Japan. These accident's teach to us must not use toxic metal level and not include or at least Pb Hg As Cd in all kind material use and intake by people, especially herbal. Herbal contamination research is beginner state that had not many papers until nowadays. Even if this pan had some papers, it had negative result and bigger and larger than problems level because of one way research trend of not many sample case-report and screening test of dried herbal form in chiefly. Many persons have afraid and risk thinking about herbal, animal and minerals since these cause. Further research related this subject will be needed at fact of epidemiology including case-control and cohort study for more precision research affecting in short and long term intake of oriental medicines

• Korean Journal of Soil Science and Fertilizer
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• v.46 no.2
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• pp.73-80
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• 2013

Due to the fact that possible risk associated with soil-crop-food chain transfer, metal contamination in croplands has become a major topic of wide concern. Accumulation of toxic metals in edible parts of crops grown in contaminated soils has been reported from number of crops including rice, soybean, wheat, maize, and vegetables. Therefore, in order to ensure food safety, measures are needed to be taken in mitigating metal pollution and subsequent uptake by crop plants. Present paper critically reviewed some of the cost effective remediation techniques used in minimizing metal uptake by crops grown in contaminated soils. Liming with different materials such as limestone ($CaCO_3$), burnt lime (CaO), slaked lime [$Ca(OH)_2$], dolomite [$CaMg(CO_3)_2$], and slag ($CaSiO_3$) has been widely used because they could elevate soil pH rendering metals less-bioavailable for plant uptake. Zn fertilization, use of organic amendments, crop rotation and water management are among the other techniques successfully employed in reducing metal uptake by crop plants. However, irrespectively the mitigating measure used, heterogeneous accumulation of metals in different crop species is often reported. The inconsistency might be attributed to the genetic makeup of the crops for selective uptake, their morphological characteristics, position of edible parts on the plants in respect of their distance from roots, crop management practices, the season and to the soil characteristics. However, a sound conclusion in this regard can only be made when more scientific evidence is available on case-specific researches, in particular from long-term field trials which included risks and benefits analysis also for various remediation practices.

• Journal of Environmental Science International
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• v.15 no.12
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• pp.1171-1175
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• 2006

Deposited road particles (DRPs) were analysed for heavy metal concentrations at four different roads in a city, Korea. The samples were collected using a roadway surface vacuum cleaning vehicle which was commonly used in collecting roadway surface particles. Six particle size ranges were analyzed separately for twelve heavy metal elements (Cd, Cr, Pb, Ni, Al, As, Co, Cu, Fe, Mn, Zn and Hg). At all sampling sites, the high concentration of the heavy metals occurred in the <74um particle size range, which conventional roadway cleaning vehicles do not remove efficiently. The Pb concentration significantly increased with decreasing particle size of DRPs, and other toxic heavy metals (Cd, Cr and Ni) also showed similar results. The heavy metal concentrations in the smaller size fraction of DRPs is important because they are contaminants that are preferentially transported by road runoff during rainfall.

• Proceedings of the Korean Society of Fisheries Technology Conference
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• 2003.05a
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• pp.158-159
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• 2003

Although the sub-chronic toxic effects of metal on fishes are well documented, that is mostly in fishes exposed to waterborne metal but few studied have been conducted on the effects of dietary metal (Handy, 1996). The realization that dietary uptake of metal is a major cause of long-term contamination in wild fish has renewed interest in the nutritional and toxicological effects of metal in the food of fishes (Handy, 1996). (omitted)

• Proceedings of the Korean Vacuum Society Conference
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• 2013.08a
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• pp.87-87
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• 2013

The interface between nanomaterials and biosystems is emerging as one of the broadest and most dynamic areas of science and technology, bringing together biology, chemistry, physics and many areas of engineering, biomedicine. The combination of these diverse areas of research promised to yield revolutionary advances in healthcare, medicine, and life science. For example, the creation of new and powerful nanosensors that enable direct, sensitive, and rapid analysis of biological and chemical species can advance the diagnosis and treatment of disease, discovery and screening of new drug molecules. Nanowire based sensors are emerging as a powerful and general platform for ultrasensitive and multiplex detection of biological and chemical species. Here, we present the studies about noble metal nanowire sensors that can be used for sensitive detection of a wide-range of biological and chemical species including nucleic acids, proteins, and toxic metal ions. Moreover, the optical and electrochemical applications of noble metal nanowires are introduced. Noble metal nanowires are successfully used as plasmonic antennas and nanoelectrodes, thereby provide a pathway for a single molecule sensor, in vivo neural recording, and molecular injection and detection in a single living cell.

• Journal of Korean Society on Water Environment
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• v.22 no.1
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• pp.37-44
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• 2006

Ecotoxicity assessments of 90 selected effluents of 22 industry types from 2002 to 2004 in Korea were evaluated by a toxic battery of bioassay test using fish Oryzias latipes, invertebrate Daphnia magna, algae Selenastrum capricornutum and bacteria Vibrio fischeri with the physicochemical measurement items and permit concentrations on the present Water Quality Conservation Act in Korea. Total toxic unit (${\Sigma}TU$) of 8 industry types of 22 industry types by the toxic battery appeared in order of the value site as follows; Pigment Dye Manufacturing (${\Sigma}TU$ 217.1) > Textile and Dye (${\Sigma}TU$ 39.3) > Semiconductor Electronic Manufacturing (Small) (${\Sigma}TU$ 25.6) > Wastewater and Sewage Treatment Plants (${\Sigma}TU$ 25.4) > Coating (${\Sigma}TU$ 23.8) > Leather Skin Manufacturing (${\Sigma}TU$ 18.0) > Synthetic Resin Manufacturing (${\Sigma}TU$ 15.6) > Assemble Metal Manufacturing (${\Sigma}TU$ 10.7). Our results demonstrate that ecotoxicity assessment, by bioassay test, is effective and practical for industrial wastewater management for 90 selected effluents with the limitation of the physicochemical permit. Among 90 effluents, 9 samples failed physicochemical permit limitation and 81 passed it. In result of ecotoxicity assessment of 90 effluents by the toxic battery, 76 effluents exhibited ecotoxicity and the others did not. The physicochemical measurement items and permit concentrations on the present Water Quality Conservation Act in Korea were low related to the ecotoxicity value by the toxic battery and appeared limited for water quality management to water-ecosystem and environment-friendly management of water.

• Proceedings of the Korean Society of Soil and Groundwater Environment Conference
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• 2003.09a
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• pp.382-385
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• 2003

QAMDI(Quantified Acid Mine Drainage Index) was developed for more synthesised, qualified and quantified assessment index which can be applied to both coal and metal mine drainage. QAMDI is calculated using three parameter groups i.e. acidity, sulfate contents and toxic metal contents. Since QAMDI expressed in terms of concentration. It reveals the different status of each mine drainage more clearly. QAMDI can be converted to the quantity of pollutant loading by being multiplied by the water flux.

• Bulletin of the Korean Chemical Society
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• v.33 no.7
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• pp.2149-2155
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• 2012

A metal-free and efficient procedure for the oxidation of alcohols into the corresponding carbonyl compounds has been described using ammonium nitrate in the presence of silica sulfuric acid under mild and heterogeneous conditions. The use of non-toxic and inexpensive materials, simple and clean work-up, short reaction times and good yields of the products are among the advantages of this method.

• Economic and Environmental Geology
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• v.31 no.6
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• pp.509-518
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• 1998

Fly ashes have been deposited around Youngwol power plant until electrostatic precipitator was installed in 1981. Fresh fly ash samples from electrostatic precipitator and weathered fly ash from ash disposal site were collected from Youngwol power plant, along with 65 soil samples of nearby area to look into the influence of PFA deposit on the soils in surrounding area. In chemistry, EPA does not contain high level of toxic elements and there is no notable concentration of toxic elements in soil near power plant. Total concentrations of Co, Cr, Cu, V, and Zn are 13 ppm, 89 ppm, 73 ppm, 157 ppm and 57 ppm in PFA. Concentrations of theses elements in ash-rich soils are 15 ppm, 78 ppm, 60 ppm, 133 ppm and 68 ppm, and those in ash-poor soils are 19 ppm, 70 ppm, 38 ppm, 91 ppm and 97 ppm. But these metal elements are highly concentrated in magnetic fractions of EPA (Co, 129 ppm; Cr, 217 ppm; Cu, 210 ppm; V, 197 ppm; Zn 90 ppm). Considering the process of long-term weathering of PFA, potentially toxic substances from the ash could be leached into soils and groundwater.