14 results match your criteria: "Chosun College of Science and Technology[Affiliation]"

Aquatic toxicity and fate of styrene oligomers in the environment.

Ecotoxicol Environ Saf

October 2023

Department of Bioenvironmental and Chemical Engineering, Chosun College of Science and Technology, 309-1 Pilmundae-ro, Dong-gu, Gwangju 61453, Republic of Korea. Electronic address:

Styrene oligomers (SOs) are ubiquitous contaminants that appear in the environment, sometimes to significant extent (see section 3.1). Despite the ongoing international debate on the human health risks posed by SOs, to the best of my knowledge, there are no studies on the aquatic toxicity and environmental fates (biodegradation and atmospheric degradation) of SOs in the environment.

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Background: This study was conducted to assess gender difference in the association of chronic kidney disease (CKD) with visceral adiposity index (VAI) and lipid accumulation product index (LAP) in Korean adults.

Materials And Methods: The study was performed using data from the 2015 Korean National Health and Nutrition Examination Survey and included 4947 adults aged 20 years or older.

Results: There were several key findings in the present study.

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Preparation and encapsulation techniques of chitosan microsphere for enhanced bioavailability of natural antioxidants.

Carbohydr Res

February 2021

Department of Bioenvironmental & Chemical Engineering, Chosun College of Science and Technology, Gwangju, 61453, Republic of Korea. Electronic address:

Reactive oxygen species (ROS), induced by medical and life irradiation, have led to diverse diseases. Natural antioxidants (NAs) have been widely used to protect the body from the harmful effects of ROS. NAs have biocompatible properties but their bioavailability in the body is very low.

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Sandy beaches as hotspots of bisphenol A.

Environ Res

December 2020

National Institute of Advanced Industrial Science and Technology (AIST), Tsukuba, Japan; Department of Applied Molecular Chemistry, College of Industrial and Technology, Nihon University (CIT & CST), 121 Izumi Narashimo, Chiba, 2758575, Japan; Albatross Alliance, Chiba, Japan.

Bisphenol A (BPA) poses a serious environmental threat and health concern. This study presents the global monitoring of BPA on oceanic sandy beaches. According to monitoring results, many beach sands contain a harmful concentrations of BPA.

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Physicochemical properties of styrene oligomers in the environment.

Sci Total Environ

September 2019

Department of Bioenvironmental and Chemical Engineering, Chosun College of Science and Technology, 309-1 Pilmundae-ro, Dong-gu, Gwangju 501-744, Republic of Korea.

Currently, styrene oligomers (SOs) are persistent contaminants that are present in the environment globally. SOs are artificial substances originating from styrene-based polymer materials, mainly including PS plastic, resin, and rubber. However, the behavior of SOs in the environment is not well-understood yet due to the scarcity of experimental data.

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Evidence of transport of styrene oligomers originated from polystyrene plastic to oceans by runoff.

Sci Total Environ

June 2019

Department of Bioenvironmental & Chemical Engineering, Chosun College of Science and Technology, 309-1 Pilmundae-ro, Dong-gu, Gwangju 501-744, Republic of Korea. Electronic address:

This study demonstrates for the first time that styrene oligomers (SOs), which are indicators of polystyrene (PS) plastic contamination in the environment, are transported from land to the ocean. Samples of sand and seawater were taken from the coastline of the Tokyo Bay over the past four years, and all samples of both sand and seawater were found to contain SOs such as styrene monomer (SM), styrene dimers (SD), and styrene trimers (ST), with the concentration distributions of these being in the order of ST > SD > SM. The concentrations of these SOs are linearly proportional to monthly precipitation.

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Vanadium oxide (VOx) thin films were deposited by an unbalanced magnetron (UBM) sputtering system with a vanadium metal target and O₂ reaction gas, and thermally treated at various annealing temperatures. In this work, the structural, electrical, and optical properties of the fabricated VOx films with various annealing temperatures were experimentally investigated. The UBM sputter grown VOx thin films exhibited amorphous structure, and had a very weak peak of V₂O (002) owing to very thin films.

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Chromium-doped carbon (Cr:C) films were fabricated by using unbalanced magnetron sputtering with chromium (Cr) and graphite (C) targets. We investigated the structural, tribological, and electrical properties of the Cr:C films fabricated with various target power densities. The surface of all the Cr:C films was smooth and uniform, and the cross section showed a more compact and clear columnar structure as the target power density increased.

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Cr metal electrode was suggested as the working electrode material to fabricate DSSCs without the TCO, and thin films were fabricated by an unbalanced magnetron sputtering system. The surface morphologies show uniform and smooth surfaces regardless of various film thicknesses, and the small crystallites of various sizes were showed with the vertical direction on the surface of Cr thin films with the increase of film thickness. And also, the root mean square (RMS) surface roughness value of Cr thin films increased, and the sheet resistance is decreased with the increase of film thickness.

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A good medical guidewires are used to introduce stents, catheters, and other medical devices inside the human body. In this study, diamond-like carbon (DLC) film was proposed to solve the poor adhesion problem of guidewire and to improve the tribological performance of guidewire. DLC films were fabricated on Si substrate by using FVA (Filtered Vacuum Arc) method.

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The objective of this study is to investigate the qualitative contribution of internal and external factors of the area contaminated by polystyrene (PS) in coastal marine environments. This study is based on the extensive results of monitoring the styrene oligomers (SOs) present in sand and seawater samples along various coastlines of the Pacific Ocean. Here, anthropogenic SOs is derived from PS during manufacture and use, and can provide clues about the origin of SOs by PS pollution.

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Monitoring of styrene oligomers as indicators of polystyrene plastic pollution in the North-West Pacific Ocean.

Chemosphere

August 2017

National Institute of Advanced Industrial Science and Technology (AIST), 16-1 Onogawa, Tsukuba, Ibaraki, 305-8569, Japan; School of Ocean and Earth Science and Technology (SOEST), University of Hawai'i at Mãnoa, 1000 Pope Rd, MSB 629, Honolulu, HI, 96822, USA. Electronic address:

Styrene oligomers (SOs) as global contaminants are an environmental concern. However, little is known on the distribution of SOs in the ocean. Here, we show the distribution of anthropogenic SOs generated from discarded polystyrene (PS) plastic monitored from the coastal ocean surface waters (horizontal distribution) and deep seawaters (vertical distribution) in the North-West Pacific Ocean.

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[Purpose] This study performed a systematic literature review of the ability of lumbar stabilization exercises (LSE) to improve the balance ability of stroke patients. [Subjects and Methods] A systematic review was conducted of four databases. The papers retrieved were evaluated based on the following inclusion criteria: 1) design, a controlled clinical trial; 2) intervention, LSE; 3) outcome, change in balance ability; and 4) year of publication, 2000 to 2013.

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The Nanolayered TiO2 photocatalysts were prepared by thermal treatment of metallic titanium chips. Photocatalytic activity for methyl ethyl ketone (MEK) and toluene was investigated using a closed circulating system. The photocatalysts were characterized by SEM and XRD.

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