• Title/Summary/Keyword: Acidic treatment

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Efficacy of Blanket Vegetation Mats on Soil and Native Groundcover Plants under Treatment of High Concentration Deicing Salt (고농도 제설제 처리에서 토양 및 자생 초화류에 미치는 Blanket 식생매트의 효용성)

  • Ju, Jin Hee;Lee, Je Man;Kim, Won Tae;Lim, Byung Ok;Seo, Nam Kyu;Yoon, Yong Han
    • Journal of Environmental Science International
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    • v.31 no.3
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    • pp.247-254
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    • 2022
  • This study investigated the effect of vegetation mat on plant growth and salt reduction in the soil treated with high concentration deicing salt. In order to measure soil chemical characteristics and plant growth, three native groundcover plants (Dendranthema zawadskii var. latilobum, Dendranthema boreale, and Kalimeris yomena) were grown in each of the three plastic containers (50.0 cm width × 35.0 cm length × 8.5 cm deep) with a high concentration treatment of calcium chloride deicing salt. There were two treatments: control, and BVM that combines B (blanket) and VM (vegetation mat). 1,600 g of soil was placed on the top of the drainage layer with 290 g of perlite, 100 seeds each of the three native plants with three repetitions were sowed, and 10 g/L of calcium chloride deicing salt was added in the treatment. As a result of the chemical properties of soil, soil in control treatment was acidic and soil electrical conductivity in BVM was the lowest. Also, exchangeable cations (K+, Ca2+, Na+, and Mg2+) in soil and all the three plants were significantly decreased in the BVM treatment. Meanwhile, the germination rate of Dendranthema zawadskii var. latilobum was the highest under high concentration deicing salt in compared to the two plants. Overall, three native groundcover plant growth was higher in the BVM than control treatment significantly. These results suggest that the treatment of blanket vegetation mat has a positive effect on soil and plant growth in soil damaged by deicing salt.

Effect of Solution Annealing Heat Treatment on the Localized Corrosion Resistance of Inconel 718 (Inconel 718의 국부 부식 저항성에 미치는 용체화 열처리의 영향)

  • Yoonhwa Lee;Jun-Seob Lee;Soon Il Kwon;Jungho Shin;Je-hyun Lee
    • Corrosion Science and Technology
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    • v.22 no.5
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    • pp.359-367
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    • 2023
  • The localized corrosion resistance of the Ni-based Inconel 718 alloy after solution heat treatment was evaluated using electrochemical techniques in a solution of 25 wt% NaCl and 0.5 wt% acetic acid. Solution heat treatment at 1050 ℃ for 2.5 hours resulted in an increased average grain diameter. Both Ti carbides (10 ㎛ diameter) and Nb-Mo carbides (1 - 9 ㎛ diameter) were distributed throughout the material. Despite heat treatment, the shape and composition of these carbides remained consistent. An increase in solution temperature led to a decrease in pitting potential value. However, the pitting potential value of solution heat-treated Inconel 718 was consistently higher than that of as-received Inconel 718 at all tested temperatures. Localized corrosion initiation occurred at 0.4 VSSE in a temperature environment of 80 ℃ for both as-received and solution heat-treated Inconel 718 alloys. X-ray photoelectron spectroscopic analysis indicated that the composition of the passive film formed on specimen surfaces remained largely unchanged after solution heat treatment, with O1s, Cr2p3/2, Fe2p3/2, and Ni2p3/2 present. The difference in localized corrosion resistance between as-received and solution heat-treated Inconel 718 alloys was attributable to microstructural changes induced by the heat treatment process.

Roles of Acid-Base Surface Interaction on Thermal and Mechanical Interfacial Behaviors of SiC/PMMA Nanocomposites (산-염기 표면반응이 탄화규소/PMMA 나노복합재료의 열적·기계적 계면특성에 미치는 영향)

  • Park, Soo-Jin;Oh, Jin-Seok
    • Korean Chemical Engineering Research
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    • v.43 no.5
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    • pp.632-636
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    • 2005
  • In this work, the effect of chemical treatments on surface properties of SiC was investigated in thermal and mechanical interfacial behaviors of SiC/PMMA nanocomposites. The acid/base value, contact angles, and FT-IR analysis were performed for the study of surface characteristics of the SiC studied. The thermal stabilities of the SiC/PMMA nanocomposites were investigated by thermogravimetric analysis (TGA). Also the mechanical interfacial properties of the composites were studied in critical stress intensity factor ($K_{IC}$) and critical strain energy release rate ($G_{IC}$) measurements. As a result, the acidically treated SiC (A-SiC) had higher acid value than that of untreated SiC (V-SiC) or basically treated SiC (B-SiC). The acidic solution treatment led to an increase in surface free energy of the SiC, mainly due to the increase of its specific component. Thermal and mechanical interfacial properties of the SiC/PMMA nanocomposites, including initial decomposition temperature (IDT), $K_{IC}$, and $G_{IC}$ had been improved in the acidic treatment on SiC. This was due to the improvement in the interfacial bonding strength, resulting from the acid-base interfacial interactions between the fillers and polymeric matrix.

The effect of human mesenchymal stem cell injection on pain behavior in chronic post-ischemia pain mice

  • Yoo, Sie Hyeon;Lee, Sung Hyun;Lee, Seunghwan;Park, Jae Hong;Lee, Seunghyeon;Jin, Heecheol;Park, Hue Jung
    • The Korean Journal of Pain
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    • v.33 no.1
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    • pp.23-29
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    • 2020
  • Background: Neuropathic pain (NP) is considered a clinically incurable condition despite various treatment options due to its diverse causes and complicated disease mechanisms. Since the early 2000s, multipotent human mesenchymal stem cells (hMSCs) have been used in the treatment of NP in animal models. However, the effects of hMSC injections have not been studied in chronic post-ischemia pain (CPIP) mice models. Here, we investigated whether intrathecal (IT) and intrapaw (IP) injections of hMSCs can reduce mechanical allodynia in CPIP model mice. Methods: Seventeen CPIP C57/BL6 mice were selected and randomized into four groups: IT sham (n = 4), IT stem (n = 5), IP sham (n = 4), and IP stem (n = 4). Mice in the IT sham and IT stem groups received an injection of 5 μL saline and 2 × 104 hMSCs, respectively, while mice in the IP sham and IP stem groups received an injection of 5 μL saline and 2 × 105 hMSCs, respectively. Mechanical allodynia was assessed using von Frey filaments from pre-injection to 30 days post-injection. Glial fibrillary acidic protein (GFAP) expression in the spinal cord and dorsal root ganglia were also evaluated. Results: IT and IP injections of hMSCs improved mechanical allodynia. GFAP expression was decreased on day 25 post-injection compared with the sham group. Injections of hMSCs improved allodynia and GFAP expression was decreased compared with the sham group. Conclusions: These results suggested that hMSCs may be also another treatment modality in NP model by ischemia-reperfusion.

Beneficial Effects of Kefir in Preventing and Treating Human Cancers (Kefir를 이용하여 다양한 Cancer 생성 예방 및 치료에 관한 연구)

  • Kim, Dong-Hyeon;Chon, Jung-Whan;Kim, Hyunsook;Lee, Soo-Kyung;Kim, Hong-Seok;Yim, Jin-Hyuk;Song, Kwang-Young;Kang, Il-Byung;Kim, Young-Ji;Jeong, Dana;Park, Jin-Hyeong;Jang, Ho-Seok;Seo, Kun-Ho
    • Journal of Dairy Science and Biotechnology
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    • v.34 no.3
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    • pp.165-172
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    • 2016
  • Kefir, originating from Caucasus, is an acidic, alcoholic fermented milk product with little acidic taste and a creamy consistency. It is recognized in having beneficial effects infor the prevention and treatment of cancer. For example, Kefir has possesses a chemopreventative effect on carcinogenesis. There has recently been a strong focus on fermented milk foods containing a mixture of several functional organic substances and various probiotic microorganisms. Hence, the purpose of this review paper was to evaluate the scientific evidence for the effects of kefir on cancer prevention and treatment. Some of we analyzed and summarized data-relating to the effects of kefir on cancer. The cacers that kefir has an effect on are as follows: colon cancer, breast cancer, leukemia, sarcoma, skin cancer, gastric cancer. This review suggests that (1) kefir could be associated with cancer prevention, (2) kefir has beneficial effects in cancer treatment, and (3) kefir has various bioactive components including peptides, polysaccharides and sphingolipids, which contribute tofor itsthese anti-cancer properties. Furthermore, furthermore, studies were performed in order to obtain as to get the scientific evidence of kefir's anticancer activity: (1) improved protective effectiveness in vivo (human subjects or animal model), (2) isolation and identification of various bioactive components, and (3) mechanisms associated with beneficial effects.

Chemical Surface Treatment of Carbon Black to Enhance Interfacial Adhesion Between Elastomer and Carbon Black (화학적 표면처리에 따른 카본블랙/고무 복합재료의 접착력 증가)

  • Kim, Jeong-Soon;Lee, Jae-Rock;Shin, Chae-Ho;Nah, Chang-Woon;Park, Soo-Jin
    • Elastomers and Composites
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    • v.34 no.3
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    • pp.222-228
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    • 1999
  • In this work, the effect of chemical treatments on the carbon blacks as-received has been studied in the context of surface, adsorption, microstructure properties, and physical surface free energetics. As an experimental result, the basic chemical treatment leads to an increase in the either dispersive or specific component without significant change the pH and specific surface area. While, acidic chemical treatment do significantly change the surface and adsorption properties, and microstructures of the carbon blacks. In particular, the result given by basic chemical treatment shows an increase of the London dispersive component of the surface free energy which is a major parameter in evaluating the dispersion or specific surface area of the carbon blacks studied. This is probably a major role in evaluating the dispersion the carbon blacks, which are reinforced in elastomer matrix in a composite system.

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A Study on the Treatment of Refractory Organics by Redox Reaction of Cu-Zn Metal Alloy (Cu-Zn 금속 합금의 산화.환원 반응에 의한 난분해성 COD처리에 관한 연구)

  • Song, Ju-Yeong;Park, Ji-Won;Kim, Jong-Hwa
    • Journal of the Korean Applied Science and Technology
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    • v.30 no.1
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    • pp.166-172
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    • 2013
  • The purpose of this study is to evaluate the treatment ability of refractory organics in hot rolling precess waste water by redox(reduction and oxidation) reaction. Metal is oxidized in an aqueous solution to generate electron which can reduce water to generate hydroxy radical. These hydroxy radical is very effective to conduct hydrogen abstraction reaction and addition reaction to the carbon - carbon unsaturated link. The surface area of metal alloy reaction material is more than enough to get equilibrium at a single treatment. The efficiency of COD treatment by redox reaction showed maximum at mild pH of pH 7 and pH 6. But it was not effective in acidic atmosphere of pH 3, 4, 5 and basic atmosphere of pH 8 or over. Redox reaction system in much more helpful in a commercial coagulation sedimentation treatment than exclusive system.

Integrated Wet Oxidation and Aerobic Biological Treatment of the Wastewater Containing High Concentration of Phenol (고농도 페놀 폐수의 습식산화와 호기성 생물학적 통합처리)

  • Choi, Ho-Jun;Lee, Seung-Ho;Yu, Yong-Ho;Yoon, Wang-Lai;Suh, II-Soon
    • KSBB Journal
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    • v.22 no.4
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    • pp.244-248
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    • 2007
  • The treatment of a model wastewater containing high concentration, 10 $g/{\ell}$, of phenol in an integrated wet oxidation-aerobic biological treatment was investigated. Partial wet oxidation under mild operating conditions was capable of converting the original phenol to biodegradable organic acids such as maleic acid, formic acid and acetic acid, the solution of which was subjected to the subsequent aerobic biological treatment. The wet oxidation was carried out at 150$^{\circ}C$ and 200$^{\circ}C$ and the initial pH of 1 to 12. The high temperature of 200$^{\circ}C$ and the acidic initial condition in the wet oxidation led to effluents of which biodegradability was higher in the subsequent biological oxidation process, as assessed by chemical oxygen demand (COD) removal. Homogeneous catalyst of $CuSO_4$ was also used for increasing the oxidation rate in the wet oxidation at 150$^{\circ}C$ and initial pH of 3.0. However, the pretreatment with the catalytic wet oxidation resulted in effluents which were less biodegradable in the aerobic biological process compared to those out of the non-catalytic wet oxidation at the same operating conditions.

Isozyme Variants in Genus Pinus by Simulated Acidic Rain (인공 산성비가 소나무속의 동위효소 양상에 미치는 영향)

  • EuiSooYoon
    • Korean Journal of Plant Resources
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    • v.10 no.4
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    • pp.305-313
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    • 1997
  • The effect of acid rain on plant isozyme response was studied with the treatment of simulated acid rain to Pinus densiflora, P. nigida and P. koraiensis for 9 months. The isozyme pattern of $\alpha$-Esterase($\alpha$-Est), Peroxidase(POD) and Glutamate dehydrogenase(GDH) were observed in the control (pH 5.6) and simulated acid rain (pH 3.5) treatment. No changes of isozyme pattern in $\alpha$-Est was observed in P. densiflora after 9 month treatment of simulated acid rain, but, two new isozymes were activated in P. nigida in the same treatment. In P. koraiensis, two new isozyme were activated but five isozymes were not activated. P. densiflora did not show any difference in POD and GDH after the treatment of simulated acid rain. P. nigida showed activation of eight and two isozymes in POD and GDH, respectively. P. koraiensis showed inactivation of 4 isozymes in POD but showed no changes In GDH.

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Environmental Pollution and Reclamation in the Abandoned Mines in Korea (국내 폐 광산 환경오염 실태 및 처리 현황)

  • Cheong Young-Wook;Min Jeong-Sik
    • 한국지구물리탐사학회:학술대회논문집
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    • 2001.09a
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    • pp.75-89
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    • 2001
  • There are 334 coal mines and about 900 metal mines abandoned. The environmental problems such as acid mine drainage from adits etc. and the subsidence has occurred in the abandoned mines. In addition, soil has been contaminated by tailings. According to analysis of mine drainages, some of them from adits in the abandoned coal and metallic mines were acidic and polluted by heavy metals. Especially, water quality of coal mine drainages were different by areas. Treatment of mine drainage by conventional chemical treatment has the drawback because the operating cost is very expensive. The treatment system used in mine drainage is the natural treatment system such as anoxic limestone drain in adits and the constructed wetland. The method of reclamation for abandoned waste rocks and tailings impoundments are mainly landfilling.

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