• Title/Summary/Keyword: thermal treatment.

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Covalent Interactions of Toluenediisocyanate with DNA and Proteins

  • Jeong, Yo-Chan;Park, Misun;Kim, Dong-Hyun
    • Toxicological Research
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    • v.14 no.4
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    • pp.525-533
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    • 1998
  • The covalent interactions of toluenediisocyanate (TDI) with macromolecules were investigated both in vitro and in vivo. In vitro incubations of 2,4- and 2,6-TDI with DNA or proteins resulted in dose-dependent formation of TDI-protein and TDI-DNA adducts. TDI-treated DNA was highly resistant to enzymatic digestion and thermal hydrolysis, but was readily hydrolyzed under acidic conditions by releasing its corresponding toluenediamine (TDA), suggesting that TDI caused the crosslinking of DNA. Reaction of TDI with albumin and globin resulted in the formation of several adducts, and some adducts were formed in blood of TDI-treated rats in a dose-dependent fashion. Administration of TDI to rats resulted also in a dose-dependent binding of TDI to hepatic tissue. Levels of TDI-albumin adducts were 10 times higher than those of TDI-globin adducts; the biological half lives of TDI-albumin and TDI-globin adducts were 1.2 and 12.5 days, respectively. Globin adducts were detected up to 28 days after the treatment. Hepatic TDI protein adducts were persistent for a substantial period whereas the levels of hepatic TDI-DNA adduct were decreased rapidly. These results indicate that the isocyanato group of TDI is not readily hydrolyzed under physiological conditions, is transported to other organs, and is bound to DNA and/or proteins without further metabolic activation. As the adducted products degrade in the body, TDA is released and introduced to the liver. TDA may additionally bind to hepatic tissue after metabolic activation. Thus, the toxic effect of TDI exposure is considered to persist during the lifetime of the adducted biological macromolecules.

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Valuable Organic Liquid Fertilizer Manufacturing through $TAO^{TM}$ Process for Swine Manure Treatment

  • Lee, Myung-Gyu;Cha, Gi-Cheol
    • Journal of Animal Environmental Science
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    • v.9 no.1
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    • pp.45-56
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    • 2003
  • $TAO^{TM}$ System is an auto-heated thermophilic aerated digestion process using a proprietary microbe called as a Phototropic Bacteria (PTB). High metabolic activity results in heat generation, which enables to produce a pathogen-free and digested liquid fertilizer at short retention times. TAO$^{TM}$ system has been developed to reduce a manure volume and convert into the liquid fertilizer using swine manure since 1992. About 100 units have been installed and operated in Korean swine farms so far. TAO$^{TM}$ system consists of a reactor vessel and ejector-type aeration pumps and foam removers. The swine slurry manure enters into vessel with PTB and is mixed and aerated. The process is operated at detention times from 2 to 4 days and temperature of 55 to $65^{\circ}C$. Foams are occurred and broken down by foam removers to evaporate water contents. Generally, at least 30% of water content is evaporated, 99% of volatile fatty acids caused an odor are removed and pathogen destruction is excellent with fecal coliform, rotavirus and salmonella below detection limits. The effluent from TAO$^{TM}$ system, called as the "TAO EFFLUX", is screened and has superb properties as a fertilizer. Normally N-P-K contents of screened TAO Efflux are 4.7 g/L, 0.375 g/L and 2.8 g/L respectively. The fertilizer effect of TAO EFFLUX compared to chemical fertilizer has been demonstrated and studied with various crops such as rice, potato, cabbage, pumpkin, green pepper, parsley, cucumber and apple. Generally it has better fertilizer effects and excellent soil fertility improvement effects. Moreover, the TAO EFFLUX is concentrated through membrane technology without fouling problems for a cost saving of long distance transportation and a commercialization (crop nutrient commodity) to a gardening market, for example.

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Pulsed electric field pasteurization of mandarin and carrot juices (Pulsed electric field 공정을 이용한 감귤 주스와 당근 주스 살균)

  • Lee, Seung Jo;Choi, Hyuk Joon;Min, Sea Cheol
    • Korean Journal of Food Science and Technology
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    • v.49 no.4
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    • pp.408-414
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    • 2017
  • Effects of pulsed electric field (PEF) processing on growth inhibition of indigenous aerobic microorganisms and the quality of mandarin and carrot juices were investigated. Mandarin juice was PEF-treated at 15-23 kV/cm for $23-241{\mu}s$, whereas carrot juice was treated at 13-14 kV/cm for 127-198 s. At $25^{\circ}C$ (inlet temperature), PEF treatments at 23 kV/cm for $104{\mu}s$ and 14 kV/cm for $198{\mu}s$ reduced the numbers of total mesophilic aerobes by $6.3{\pm}0.8$ and $5.5{\pm}0.9{\log}\;CFU/mL$ in mandarin juice and carrot juice, respectively. Elevation of inlet temperature to $40^{\circ}C$ increased the reduction rates in both juices. In general, the treatments resulting in the highest microbial inhibition at 25 and $40^{\circ}C$ did not alter the physicochemical and nutritional properties of both juices (p>0.05). PEF is a feasible technology to pasteurize mandarin and carrot juices commercially, with minimal quality deterioration.

Sensory Quality Attributes of Takju and Their Changes During Pasteurization (탁주의 관능적 품질요소와 이들의 열처리에 의한 변화)

  • Lee, Cherl-Ho;Lee, Hyun-Duck;Kim, Ji-Yong;Kim, Ki-Myung
    • Journal of the Korean Society of Food Culture
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    • v.4 no.4
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    • pp.405-410
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    • 1989
  • The sensory quality describing terms of Takju were surveyed by questionair and classified according to the sensory characteristics. The effects of thermal treatment for the pasteurization of Takju on the sensory quality were tested and statistically evaluated. The important sensory quality attributes of Takju were white, gray, and yellow for color, acidic and yeasty for smell, sour, astringent, bitter and sweet for taste and gritty, viscous and carbonated for mouthfeel. The organoleptic properties of grayness, yeasty and cooked smell, astringent and bitter taste and thickness increased, while sourness, sweetness, yellowness, grittiness and carbonated feel decreased by the pasteurization treatments, heating $82^{\circ}C$, $93^{\circ}C$ or $135^{\circ}C$ for 9 seconds. These changes coincided with the overall reductions in the preference scores of pasteurized Takju. The degree of sensory quality deterioration appeared to be affected to some extent by the heating temperature.

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Thermal-Induced Osteonecrosis of Adjacent Vertebra after Intradiscal Electrothermal Therapy

  • Kim, Soonjoon;Lee, Sun-Ho;Kim, Eun-Sang;Eoh, Whan
    • Journal of Korean Neurosurgical Society
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    • v.60 no.1
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    • pp.114-117
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    • 2017
  • A 42-year-old man was admitted to our hospital with complaints of low back pain and intermittent right thigh pain. Twelve weeks before admission, the patient received intradiscal electrothermal therapy (IDET) at a local hospital. The patient still reported low back pain after the procedure that was managed with narcotic analgesics. Follow-up magnetic resonance imaging (MRI) was performed, and his referring physician thought the likely diagnosis was spondylodiscitis at the L4-5 spinal segment with a small epidural abscess. At admission to our department, the patient reported aggravated low back pain. Blood test results, including the erythrocyte sedimentation rate and C-reactive protein levels, were slightly elevated. Biopsy samples of the L4, L5 vertebral bodies and disk were obtained. The material underwent aerobic, anaerobic, fungal, mycobacterial cultures and histologic examination. Results of all cultures were negative. Histologically, necrosis of the bone was evident from the number of empty osteocyte lacunae. In addition, there was no evidence of infection based on biopsy results. No antibiotic treatment was administered on discharge. Repeat computed tomography and MRI performed 12 months after IDET showed a bony defect in the L4 and L5 vertebral bodies, and a decrease in the size of the L4-5 intervertebral disc lesion. We report a case of lumbar vertebral osteonecrosis induced by IDET and discuss etiology and radiologic features.

The Quality Properties in Herbal Tea Containing Astragalus membranaceus, Schizandra chinensis, Liriope platyphylla and Platycodon grandiflorum which are affected by the Processing Conditions (가공조건에 따른 황기, 오미자, 맥문동 및 길경을 첨가한 한방차의 품질 특성)

  • Oh, Sung-Cheon
    • Journal of the Korean Applied Science and Technology
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    • v.31 no.3
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    • pp.534-540
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    • 2014
  • The analysis of the change in the herbal tea composition according to the difference in processing conditions result. Was slightly reduced crude is treated ash puffing process was relatively increased, moisture, crude protein, the solid elution rate than the roasting process. Benzopyrene content was significantly reduced to 0.18 ppb from 0.35 ppb. Generation of food $B({\alpha})P$ is mainly include the thermal decomposition of food cooking, when the processing which is a main component of food carbohydrate, protein, fat reason despite severe heat treatment as a whole is to be detected even though the $B({\alpha})P$ in this way is considered to be. Generally the taste, aroma and color did not show a big difference but tasted quite stuffy and the strong sour taste reduced its preference.

A Study on the Design and Fabrication of Fat Emulsification Adapted Focused Ultrasonic Transducer (지방 조직 유화를 위한 집속형 초음파 변환기 설계 및 제작에 관한 연구)

  • Kim, Ju-Young;Kim, Jae-Young;Jung, Hyun-Du;Noh, Si-Cheol;Mun, Chang-Su;Mun, Chi-Woong;Choi, Heung-Ho
    • Journal of the Institute of Electronics and Information Engineers
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    • v.52 no.11
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    • pp.127-134
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    • 2015
  • Tissue stimulation technique using ultrasound has been continuously studied and developed. Recently, as a increment of interests for obesity treatment and cosmetic care, a various studies on ultrasonic fat emulsification has been conducted. In this study, the fat emulsification adapted ultrasonic transducer was designed. And using designed transducer, the simulation for the shape of focal area and thermal degradation region was conducted. The dimensions were verified by the simulation results. And the effectiveness was confirmed by evaluating measured radiation characteristic and heating characteristic. In addition, we estimated the ultrasonic heating characteristics in composite structure medium. The shape of focal point and heating characteristic of the proposed transducer were determined to be sufficient to emulsify the fat. The results of this study are considered to be used as basic research in more efficient and safe ultrasonic fat removal.

Effects of Oxygen Plasma-treated Graphene Oxide on Mechanical Properties of PMMA/Aluminum Hydroxide Composites (산소 플라즈마 처리된 그래핀 산화물이 PMMA/수산화알루미늄 컴포지트의 기계적 물성에 미치는 영향)

  • Kim, Hyo-Chul;Jeon, Son-Yeo;Kim, Hyung-Il;Choi, Ho-Suk;Hong, Min-Hyuk;Choi, Ki-Seop
    • Polymer(Korea)
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    • v.35 no.6
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    • pp.565-573
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    • 2011
  • The nanocomposites containing graphene oxide (GO) were prepared in order to improve the mechanical properties of poly(methyl methacrylate)/aluminum hydroxide (PMMA/AH) composites. GO was prepared from graphite by oxidation of Hummers method followed by exfoliation with thermal treatment. The surface of GO was modified by oxygen plasma in various exposure times from 0 to 70 min to improve interfacial compatibility. Compared with PMMA/AH composites, the nanocomposites containing GO modified with oxygen plasma for the exposure time up to 50 min showed significant increases in flexural strength, flexural modulus, Rockwell hardness, Barcol hardness, and Izod impact strength. The morphology of fracture surface showed an improved interfacial adhesion between PMMA/AH composites and GO, which was properly treated with oxygen plasma. The mechanical properties of nanocomposites were deteriorated by increasing the content of GO above 0.07 phr due to the nonuniform dispersion of GO.

Preparation and Characterization of Poly(vinyl alcohol) Hydrogel Contain Metronidazole by Irradiation (감마선을 이용한 Metronidazole이 함유된 Poly(vinyl alcohol) 하이드로겔 제조 및 특성)

  • Baik, Jae;Park, Jong-Seok;Jong, Jin-Oh;Jeong, Sung In;Gwon, Hui-Jeong;Ahn, Sung-Jun;Lim, Youn-Mook
    • Journal of Radiation Industry
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    • v.10 no.1
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    • pp.21-27
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    • 2016
  • Periodontitis is disease of damaged gum tissue that is not removed the plaque onto teeth. In case that the symptoms of disease get pain worse, it will have to extract tooth because of tumefy or bleeding at gums so treatment of drug was required to periodontitis. In this study, the hydrogel was prepared by including superior viscous, excellent elastic, and biocompatibility of Poly(vinyl alcohol, PVA) and antimicrobial drug of Metronidazole (MD). The 15 wt% PVA was dissolved in deionized water and then prepared PVA solution was irradiated using gamma-ray at 25 kGy ($10kGy\;hr^{-1}$). In addition, PVA hydrogel was immersed in each 0.1, 0.25 and 0.5 wt% MD solution using stirrer for 24 hr. The result of the gelation, 0.5 wt% MD loaded PVA hydrogel(76%) was lower than PVA hydrogel (88.2%). The swelling ration of 0.5 wt% MD loaded PVA hydrogel (294.8%) was higher than PVA hydrogel (105.2%). The compressive strength and thermal properties of MD loaded PVA hydrogel was gradually lower. The drug release test of 0.5 wt% MD loaded PVA hydrogel (61%) was higher than 0.1 wt% MD loaded PVA hydrogel (12%). Therefore, MD loaded PVA hygrogel may be a promising tool for periodontitis medicine by gamma-ray.

Investigation of short-term stability in high efficiency polymer : nonfullerene solar cells via quick current-voltage cycling method

  • Lee, Sooyong;Seo, Jooyeok;Kim, Hwajeong;Song, Dong-Ik;Kim, Youngkyoo
    • Korean Journal of Chemical Engineering
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    • v.35 no.12
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    • pp.2496-2503
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    • 2018
  • The short-term stability of high efficiency polymer : nonfullerene solar cells was investigated by employing a quick (ten cycles) current density-voltage (J-V) cycling method. Polymer : nonfullerene solar cells with initial power conversion efficiency (PCE) of >10% were fabricated using bulk heterojunction (BHJ) films of poly[(2,6-(4,8-bis(5-(2-ethylhexyl)thiophen-2-yl)-benzo[1,2-b:4,5b']dithiophene))-alt-(5,5-(1',3'-di-2-thienyl-5,7'-bis(2-ethylhexyl)benzo[1',2'-c:4',5'-c']dithiophene-4,8-dione))] (PBDB-T) and 3,9-bis(2-methylene-((3-(1,1-dicyanomethylene)-6/7-methyl)-indanone))-5,5,11,11-tetrakis(4-hexylphenyl)-dithieno[2,3-d:2',3'-d']-s-indaceno[1,2-b:5,6-b']dithiophene (IT-M). One set of the BHJ (PBDB-T : IT-M) films was thermally annealed at $160^{\circ}C$ for 30min, while another set was used without any thermal treatment after spin-coating. The quick J-V scan (cycling) measurement disclosed that the PCE decay was relatively slower for the annealed BHJ layers than the unannealed (as-cast) BHJ layers. As a result, after ten cycles, the annealed BHJ layers delivered higher PCE than the unannealed BHJ layers due to higher and more stable trend in fill factor. The present quick J-V cycling method is simple but expected to be useful for the prediction of short-term stability in organic solar cells.