• Title/Summary/Keyword: chemical-based agent

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Life Cycle Assessment on Process of Wet Tissue Production (물티슈 제조공정의 전과정 평가)

  • Ahn, Joong Woo
    • Clean Technology
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    • v.24 no.4
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    • pp.269-274
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    • 2018
  • In this study, Life Cycle Assessment (LCA) of wet tissue manufacturing process was performed. The wet tissue manufacturing process consists of preparation of wetting agent (chemical liquid), impregnation of nonwoven fabric into wetting agent and primary and secondary packaging. Data and information were collected on the input and output of the actual process from a certain company and the database of the Korea Ministry of Environment and some foreign countries (when Korean unavailable) were employed to connect the upper and the lower process flow. Based on the above and the potential environmental impacts of the wet tissue manufacturing process were calculated. As a result of the characterization, Ozone Layer Depletion (OD) is 3.46.E-06 kg $CFC_{11}$, Acidification (AD) is 5.11.E-01 kg $SO_2$, Abiotic Resource Depletion (ARD) is $3.52.E+00\;1yr^{-1}$, Global Warming (GW) is 1.04.E+02 kg $CO_2$, Eutrophication (EUT) is 2.31.E-02 kg ${PO_4}^{3-}$, Photochemical Oxide Creation (POC) was 2.22.E-02 kg $C_2H_4$, Human Toxicity (HT) was 1.55.E+00 kg 1,4 DCB and Terrestrial Ecotoxicity (ET) was 5.82.E-04 kg 1,4 DCB. In order to reduce the environmental impact of the manufacturing process, it is necessary to improve the overall process as other general cases and change the raw materials including packaging materials with less environmental impact. Conclusively, the energy consumed in the manufacturing process has emerged as a major issue, and this needs to be reconsidered other options such as alternative energy. Therefore, it is recommended that a process system should be redesigned to improve energy efficiency and to change to an energy source with lower environmental impact. Due to the nature of LCA, the final results of this study can be varied to some extent depending on the type of LCI DB employed and may not represent of all wet tissue manufacturing processes in the current industry.

Synthesis of Polyimide Crosslinked Silica-based Aerogel with Enhanced Mechanical Properties and Its Physico-chemical Properties (폴리이미드 가교로 기계적 강도가 향상된 실리카 기반 에어로겔의 합성 및 물리화학적 특성 분석)

  • Kim, Jiseung;Choi, Haryeong;Kim, Taehee;Lee, Wonjun;Lee, Hong-Sub
    • Journal of the Microelectronics and Packaging Society
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    • v.29 no.4
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    • pp.9-14
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    • 2022
  • Silica aerogel is a porous material with a very low density and high specific surface area. Still, its application is limited due to its weak mechanical properties due to structural features. To solve this problem, a method of complexing it with various polymers has been proposed. We synthesized polyimide cross-linked silica aerogel by the sol-gel process to obtain high mechanical properties. Tetraethyl orthosilicate (TEOS) was used as a precursor to make silica aerogel, and 3- aminopropyltriethoxysilane (APTES) was used as a coupling agent for cross-linking polyimide. Polyimide was synthesized using pyromellitic dianhydride and 3,5-diaminobenzoic acid, and mechanical properties were improved by crosslinking polyimide with 10 repeating units in the polyimide chain using the reaction formula ${\frac{n_1}{n_2}}={\frac{n}{n+1}}$ To realize silica aerogel, polyimide having various weight ratios was added before gelation, resulting in a 19-fold or greater increase in maximum compressive strength compared to pure silica aerogel. From this study, an enhancement of silica aerogel could be enhanced through polymer cross-linking bonds.

Isolation and Characterization of Burkholderia cepacia EB215, an Endophytic Bacterium Showing a Potent Antifungal Activity Against Colletotrichum Species (탄저병균에 길항력이 우수한 식물내생세균 Burkholderia cepacia EB215의 분리 및 특성 규명)

  • Park Ji Hyun;Choi Gyung Ja;Lee Seon-Woo;Jang Kyoung Soo;Lim He Kyoung;Chung Young Ryun;Cho Kwang Yun;Kim Jin-Cheol
    • Microbiology and Biotechnology Letters
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    • v.33 no.1
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    • pp.16-23
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    • 2005
  • In order to develop a new microbial fungicide using endophytic bacteria for the control of anthracnoses occurring on various crops, a total of 260 bacterial strains were isolated from fresh tissues of 5 plant species. After they were cultured in broth medium, their antifungal activities were tested for in vivo antifungal activity against cucumber anthracnose caused by Colletotrichum orbiculare. As the results, liquid cultures of 28 strains showed potent antifungal activities more than $90\%$ against cucumber anthracnose. At 3-fold dilutions of liquid cultures, 18 strains inhibited the development of cucumber anthracnose of more than $70\%$. They were further tested for in vivo antifungal activity against red pepper anthracnose caused by C. coccodes and in vitro antifungal activity against C. acutatum, a fungal agent causing red pepper anthracnose. Among 18 strains, a bacterial strain EB215 isolated from cucumber roots displayed the most potent antifungal activity against Colletotrichum species. It was identified as Burkholderia cepacia based on its physiological and biochemical characteristics, Biolog test and 16S rDNA gene sequence. It also controlled effectively the development of rice blast (Magnaporthe grisea), rice sheath blight (Corticium sasaki), tomato gray mold (Botrytis cinerea), and tomato late blight (Phytophthora infestans). Studies on the characterization of antifungal substances produced by B. cepacia EB215 are in progress.

Simultaneous Removal of NO and SO2 using Microbubble and Reducing Agent (마이크로버블과 환원제를 이용한 습식 NO 및 SO2의 동시제거)

  • Song, Dong Hun;Kang, Jo Hong;Park, Hyun Sic;Song, Hojun;Chung, Yongchul G.
    • Clean Technology
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    • v.27 no.4
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    • pp.341-349
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    • 2021
  • In combustion facilities, the nitrogen and sulfur in fossil fuels react with oxygen to generate air pollutants such as nitrogen oxides (NOX) and sulfur oxides (SOX), which are harmful to the human body and cause environmental pollution. There are regulations worldwide to reduce NOX and SOX, and various technologies are being applied to meet these regulations. There are commercialized methods to reduce NOX and SOX emissions such as selective catalytic reduction (SCR), selective non-catalytic reduction (SNCR) and wet flue gas desulfurization (WFGD), but due to the disadvantages of these methods, many studies have been conducted to simultaneously remove NOX and SOX. However, even in the NOX and SOX simultaneous removal methods, there are problems with wastewater generation due to oxidants and absorbents, costs incurred due to the use of catalysts and electrolysis to activate specific oxidants, and the harmfulness of gas oxidants themselves. Therefore, in this research, microbubbles generated in a high-pressure disperser and reducing agents were used to reduce costs and facilitate wastewater treatment in order to compensate for the shortcomings of the NOX, SOX simultaneous treatment method. It was confirmed through image processing and ESR (electron spin resonance) analysis that the disperser generates real microbubbles. NOX and SOX removal tests according to temperature were also conducted using only microbubbles. In addition, the removal efficiencies of NOX and SOX are about 75% and 99% using a reducing agent and microbubbles to reduce wastewater. When a small amount of oxidizing agent was added to this microbubble system, both NOX and SOX removal rates achieved 99% or more. Based on these findings, it is expected that this suggested method will contribute to solving the cost and environmental problems associated with the wet oxidation removal method.

Selection of Indicator Insects for the Evaluation of Agricultural Environment (농업환경 평가를 위한 지표곤충 선발)

  • Choi Young-Cheol;Park Hae-Chul;Kim Jong-Gill;Sim Ha-Sik;Kwon Oh-Seok
    • Korean journal of applied entomology
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    • v.43 no.4 s.137
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    • pp.267-273
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    • 2004
  • To select indicator insects, the abundance of which is one of the major criteria for the evaluation of agricultural environment, was designated and monitored in the three sites (Hongcheon A, B, and Yangpyeong) from 2001 to 2003. Characteristics of rice cultivation are usual cultivation with 2 or 3 times sprayed chemical agents per year in Hongcheon A site, duck cultivation with non-sprayed chemical agent, green manure and mowing in Hongcheon B site, and pond snail with non-sprayed chemical agent, green manure and mowing in Yangpyeong site. Dominant floral species are Digitaria ciliaris (Retz.) Koel., Persicaria thunbergii (Siebold & Zuccarini) H. Gross, Echinochioa crus-galli (L.) Beauvois, and Humulus scandens (Lour.) Merr. in Hongcheon A site, Digitaria ciliaris (Retz.) Koel., Persicaria thunbergii (Siebold & Zuccarini) H. Gross, and Echinochloa crus-galli (L.) Beauvois in Hongcheon B site, and Digitaria ciliaris (Retz.) Koel., Setaria viridis (L.) Beauv., and Persicaria langiseta (De Btuyn) Kitagawa in Yangpyeong site. Degree of green naturality (DGN) was higher in Hongcheon B site (2.0) and Yangpyeong site (3.6) than in Hongcheon A site (1.6). Number of species and individual of insects collected in the three sites were abundant on August and September. The species diversity was higher in Hongcheon B and Yangpyeong than in Hongcheon A. And Coleoptera was dominant in the all sites. The dominance index (DI) was the lowest, but diversify index (H'), evenness index (E) and richness index (RI) were the highest in Hongcheon B site. Based on three results, indicator insects for the evaluation of agricultural environment were selected as Dolichus halensis in Hongeheon A site, as Pheropsophus. javanus and Polionemobius mikado in Hongcheon B and Yangpyeong sites.

Evaluation of Cleaning Ability of Aqueous Cleaning Agents according to their Additives (수계세정제의 첨가제에 따른 세정성 평가연구)

  • Kim, Hansung;Bae, Jae Heum
    • Clean Technology
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    • v.12 no.1
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    • pp.1-9
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    • 2006
  • Aqueous cleaning agents which are considered to be environmental-friendly and promising alternative ones among various industrial cleaning agents were evaluated in this words. In order to formulate aqueous cleaning agents, primary alcohol ethoxylates with 3, 5 and 7 moles of ethylene oxides among nonionic surfactants were selected as main surfactants. And anionic surfactants and alcohols were chosen as their cosurfactants. Builders such as NaOH, KOH, $Na_2CO_3$ and $NaHCO_3$ were also evaluated as additives for improvement of cleaning efficiency of aqueous cleaning agents. The experimental results of cleaning ability tests show that introduction of anionic surfactant TLS as cosurfactant in alcohol ethoxylate-based aqueous solution gives the best cleaning efficiency for removing mixed soil of cutting oil and grease. NaOH and $Na_2CO_3$ are also shown to play an important role for improvement of cleaning efficiency in a aqueous cleaning agent.

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Anti-nociceptive Activity of Acer tegmentosum MeOH Extract (산청목 메탄올 추출물의 진통 효과)

  • Seo, Hyun Won;Park, Kyung Jae;Guahk, Gui Hee;Im, Jun Sang;Kim, Dae Keun;Leem, Jae Yoon;Cha, Dong Seok;Kwon, Jin;Oh, Chan Ho;Jeon, Hoon
    • Korean Journal of Pharmacognosy
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    • v.44 no.2
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    • pp.188-192
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    • 2013
  • Acer tegmentosum which is belongs to Aceraceae has been widely used as a traditional medicine for the treatment of lots of diseases including pain management. In this study, we evaluated the anti-nocicepitve effects of methanolic extract of A. tegmentosum (MAT) in mice using various pain models. MAT presented strong and dose-dependent anti-nociceptive activities on thermal nociception models such as tail-immersion test and hot plate test. Moreover, acetic acid-induced chemical nociception was signigicantly reduced by MAT treatment. We could confirm MAT's central and peripheral analgesic properties by formalin test. We also found that the pre-treatment of opioid receptor antagonist did not alter the MAT's anti-nociception, suggesting opioid receptor is not involved in analgesic activity of MAT. Based on our results, we could conclude that MAT may be possibly used as an anti-nociceptive agent for the treatment of various nociceptive pains.

Preparation of Flexible and Light Thermal Insulating Ceramic Composites Using Foaming Technology (발포공정을 이용한 경량의 연질 세라믹 보온단열재의 제조)

  • Lee, Chul-Tae
    • Applied Chemistry for Engineering
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    • v.26 no.1
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    • pp.59-66
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    • 2015
  • A new concept of an inorganic foaming process at low temperature was demonstrated for the production of inorganic thermal insulating materials with the properties of flexible light-weight, the advantages of organic-based thermal insulation material. The foaming process was proceeded by establishing a skeleton of the foam body by using inorganic fibrous sepiolite and aluminum silicate. A cavity was formed by the expansion of fibrous skeleton body, by the gas which was generated from foaming agent at low temperature. Then the multi-vesicular expanded perlite with low thermal conductivity was filled into the cavity in a skeleton of the foam body. Finally through these overall process, a new inorganic foamed body could be obtained at low temperature without the hot melting of inorganic materials. In order to achieve this object, various preparations such as fibrous sepiolite fibrillation process, heat treatment process of the fibrous slurry were needed, and the optimal compositional condition of slurry was required. The foam body produced showed the properties of flexible light-weight thermal insulation materials such as bulk density, yield strength, flexural strength, and high heat resistance.

Production of Oleamide, a Functional Lipid, by Streptomyces sp. KK90378

  • Kwon, Jeong-Ho;Hwang, Sung-Eun;Han, Jae-Taek;Kim, Chang-Jin;Rho, Jung-Rae;Shin, Jong-Eon
    • Journal of Microbiology and Biotechnology
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    • v.11 no.6
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    • pp.1018-1023
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    • 2001
  • Oleamide (cis-9-octadecenamide) is endogenous primary amide of fatty acid that is produced in small amounts in animal brains. It is known to induce sleep and to lower temperature by destroying the lipid plasma membrane structure of cells, thereby disclosing gap junction channels. To develop a new biological production method for oleamide, a screening program was conducted to isolate a microorganism producing oleamide. Among 1,500 soil microorganisms tested, KK90378 exhibited a potent positive reaction with Dragendoff`s reagent, used to detect the primary amide of oleamide. KK90378 was identified as a Streptomyces species based on cultural and morpohological characteristics, the presence of diaminopimelic acid in the cell wall, and the sugar patterns for the whole-cell extrat. Streptomyces sp. KK90378 produced oleamide 3 days after culture at $28^{\circ}C$, pH 7.2 A series of purification steps, including hexane extraction, silica gel column, and preparative thin layer chromatographies, were performed for the purification of oleamide. A spectrophotometric analysis using $^1H$, $^13C$-NMR, and GC-MS confirmed that the chemical structure of the purified oleamide was identical to that of authentic oleamide.

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Antagonistic Activity against Dirty Panicle Rice Fungal Pathogens and Plant Growth-Promoting Activity of Bacillus amyloliquefaciens BAS23

  • Saechow, Sukanya;Thammasittirong, Anon;Kittakoop, Prasat;Prachya, Surasak;Thammasittirong, Sutticha Na-Ranong
    • Journal of Microbiology and Biotechnology
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    • v.28 no.9
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    • pp.1527-1535
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    • 2018
  • Bacterial strain BAS23 was isolated from rice field soil and identified as Bacillus amyloliquefaciens. Based on dual culture method results, the bacterium BAS23 exhibited potent in vitro inhibitory activity on mycelial growth against a broad range of dirty panicle fungal pathogens of rice (Curvularia lunata, Fusarium semitectum and Helminthosporium oryzae). Cell-free culture of BAS23 displayed a significant effect on germ tube elongation and mycelial growth. The highest dry weight reduction (%) values of C. lunata, H. oryzae and F. semitectum were 92.7%, 75.7%, and 68.9%, respectively. Analysis of electrospray ionization-mass spectrometry (ESI-MS) and $^1H$ nuclear magnetic resonance (NMR) spectroscopy revealed that the lipopeptides were iturin A with a C14 side chain (C14 iturinic acid), and a C15 side chain (C15 iturinic acid), which were produced by BAS23 when it was cultured in nutrient broth (NB) for 72 h at $30^{\circ}C$. BAS23, the efficient antagonistic bacterium, also possessed in vitro multiple traits for plant growth promotion and improved rice seedling growth. The results indicated that BAS23 represents a useful option either for biocontrol or as a plant growth-promoting agent.