• Title/Summary/Keyword: PEG treatment

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Effect of Osmoconditioning on the Germination of ltalian Ryegrass and Sorghum (삼투압 조절이 Italian ryegrass와 수수종자의 발아에 미치는 영향)

  • 허삼남
    • Journal of The Korean Society of Grassland and Forage Science
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    • v.10 no.3
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    • pp.121-128
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    • 1990
  • Germination of Italian ryegrass and sorghum were measured at a range of temperatures and with PEG treatment at several different levels of concentration and treatment period to evaluate the effects of osmoconditioning with polyethylene glycol(PEG-8000). The results obtained are summarized as follows: 1. Cumulative germination percentage of intact Italian ryegrass seeds did not show much difference among temperatures, while that of sorghum seeds decreased markedly at low temperature. 2. Italian ryegrass seeds osmoconditioned with 20% PEG solution for two days at 10^{\circ}C.$ accelerated germination at 10^{\circ}C.$, with injurious effect of osmoconditioning at higher temperature for many days. 3. Osmoconditioning with 20% PEG solution for two or four days at 10^{\circ}C.$ increased germination of sorghum seeds, while the seeds treated at higher temperatures for long period suppressed germination.

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Chemical Treatment of the PCBs-laden Transformer Insulation Oil (PCBs 함유 변압기 절연유의 화학적처리)

  • Ryoo, Keon-Sang;Choi, Jong-Ha;Choi, Jin-Whan
    • Journal of Environmental Science International
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    • v.20 no.11
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    • pp.1499-1507
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    • 2011
  • Practical disposal of transformer insulation oil laden with PCBs (polychlorinated biphenyls) by a chemical treatment has been studied in field work. The transformer insulation oil containing PCBs was treated by the required amounts of PEG (polyethylene glycol) and KOH, along with different reaction conditions such as temperatures and times. The reaction of PEG with PCBs under basic condition produces arylpolyglycols, the products of nucleophilic aromatic substitution. Removal efficiencies of PCBs in insulation oil before and after chemical treatment were examined. The removal efficiency of PCBs was very low at lower temperatures of 25 and $50^{\circ}C$. Under the reaction condition of PEG 600/KOH/$100^{\circ}C$/2hr, removal efficiency of PCBs was approximately 70%, showing completely removal of PCBs containing 7~9 chlorines on biphenyl frame which appear later than PCB IUPAC Number 183 (2,2',3,4,4',5',6-heptaCB) in retention time of GC/ECD. However, when increasing the reaction temperature and time to $150^{\circ}C$ and 4 hours, removal efficiency of PCBs reached 99.99% without any formation of PCDDS/PCDFs during the process. Such reaction conditions were verified by several official analytical institutions. In studying the reaction of PEG with PCBs, it confirmed that the process of chemical treatment led to less chlorinated PCBs through a stepwise process with the successive elimination of chlorines.

Study on the Hybridization of Polymer-macromers for the Dimensional Stabilization of Woody Materials (치수안정화를 위한 목질재료의 고분자 하이브리드화에 관한 연구)

  • Lim, Kie-Pyo;Cho, Chong-Su;Kim, Ik-Joo;Na, Eun-Sun
    • Journal of the Korean Wood Science and Technology
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    • v.23 no.4
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    • pp.1-9
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    • 1995
  • This study was carried out to experiment the dimensional stabilization of woods of red pine (Pinus densiflora S. et Z.) and sugi(Cryptomeria japonica D. Don) by vacuum impregnation of polyehtylene glycols(PEG) with mo. wt. 200, 400, 600, 1000; polypropylene glycols (PPG) with mo. wt. 425,725 ; PEG-acryloylates, and PPG-acryloylates synthesized, and then by water soaking. The results obtained are as follows: 1. The density of sapwood and heartwood was different from each other in both species. 2. The PEG and PEG-macromers with lower molecular weight by impregnation has increased the density of wood specimens more higher, thereby caused their higher volume expansion, and those with higher molecular weight than 600 has tended to down their density increment. 3. Before and after water soaking, the density decrease of specimen impregnated was high in woods impregnated with simple PEG and PPG, while lower in specimens impregnated with PEG-macromers and PPG-macromers. 4. So PEG-macromer was expected to hold the original dimension of decayed wood for antiques, but it was necessary to develop another penetration method as well as aqueous solvent.

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Polyethylene Glycol Plus Electrolytes with Stimulant Laxative in Paediatric Faecal Disimpaction: A Randomised Controlled Study

  • Acharyya, Bhaswati C;Bhattacharyya, Chandrayee;Mukhopadhyay, Meghdeep;Acharyya, Saumyabrata
    • Pediatric Gastroenterology, Hepatology & Nutrition
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    • v.24 no.2
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    • pp.230-237
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    • 2021
  • Functional constipation is common in the paediatric population all over the world. Effective disimpaction to evacuate the impacted faecal matter forms an essential initial step in the management of constipation. Though different regimens of polyethylene glycol 3350 with electrolytes (PEG+E) are accepted as the prime medication for disimpaction, response is not always satisfactory. A randomised prospective study was undertaken, in a tertiary paediatric Gastroenterology centre to find out the outcome of a 2-day disimpaction when a stimulant laxative sodium picosulphate was added to PEG3350+E (PEG+E+PS group) and comparing it with the outcome using PEG3350+E (PEG+E group) alone. Hundred and one children were randomised into two groups to receive PEG+E+PS and PEG+E. Results revealed that PEG+E+PS group proved significantly superior to PEG+E group in most of the efficacy-parameters in terms of disimpaction as well as long-term management of constipation. Though stimulant laxatives are being used for disimpaction, comparative data are lacking. This was the 1st such comparative study looking at the efficacy of these two processes of disimpaction along with long term effect on treatment.

Humidity Controlled Drying for the Fragments of an Wooden Boat in the Neolithic Age, Excavated from Bibong-ri, Changnyeong, Korea (창녕 비봉리 출토 신석기시대 나무배 편의 조습건조)

  • Kim, Soochul;Lee, Kwanghee
    • Conservation Science in Museum
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    • v.14
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    • pp.7-12
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    • 2013
  • The conservation has been conducted for the fragments of an wooden boat in the Neolithic Age, excavated from Bibong-ri, Changnyeong, Korea. The vacuum-freeze drying have been applied to mostly to the small relics, such as wooden lacquerwares or small wooden goods etc.. Therefore, the large objects like a wooden boats have been treated almost by air-drying after impregnation with aqueous PEG solution. The air-drying is needed to impregnate with PEG aqueous solution during long period and run the risk of the fault generation. This report explain an example adapted for the fragments of the wooden boat by humidity-controlled drying(HCD) with slow adjusting moisture content. We did the chemical pre-treatment, PEG aqueous solution. The concentration of the aqueous solution was increased gradually from 10% to 80%. After the impregnation, the objects were dried by the HCD. The dimensional stability of the fragments after treatment was good.

Compressive Strength of Waterlogged Archaeological Wood after PEG Treatment with Concentration and Solvent (PEG 처리 수침고목재의 농도 및 용매에 따른 압축강도 변화)

  • Kim, Soo-Chul
    • Journal of Conservation Science
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    • v.28 no.2
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    • pp.95-99
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    • 2012
  • The compressive strength of PEG along processing concentration and solvent is willing to be measured and proper processing condition for exhibition and storage is also willing to be measured by comparing with dimensional stability. In the advanced research of setting PEG-preprocessing concentration & solvent for freeze drying of waterlogged archaeological wood of high water content, vacuum freeze drying showed the highest dimension stability after 40% PEG-preprocessing of aqueous solution. In this study, the compressive strength increased in proportion of processing concentration and water showed the relatively-higher compressive strength than t-butanol regarding solvent. Especially, it showed that there is no big strength difference between PEG 40% and PEG 50% in aqueous solution by 6.6%(16kgf/$cm^2$). According to the above results, it was recognized that it is most effective to implement freeze drying after 40% PEG-preprocessing when want to dimensional stability and compressive strength simultaneously.

Performance of PEG on immobilization of zero valent metallic particles on PVDF membrane for nitrate removal

  • Chan, Yi Shee;Chan, Mieow Kee;Ngien, Su Kong;Chew, Sho Yin;Teng, Yong Kang
    • Membrane and Water Treatment
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    • v.9 no.1
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    • pp.1-7
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    • 2018
  • The principal objective of this study is to investigate the effect of Polyethylene Glycol (PEG) crosslinking in Polyvinylidene Fluoride (PVDF) in immobilization of Fe and bimetallic Fe/Cu and Cu/Fe zero valent particles on the membrane and its efficiency on removal of nitrate in wastewater. PVDF/PEG polymer solution of three weight compositions was prepared to manipulate the viscosity of the polymer. PEG crosslinking was indirectly controlled by the viscosity of the polymer solution. In this study, PEG was used as a modifier of PVDF membrane as well as a cross-linker for the immobilization of the zero valent particles. The result demonstrates improvement in immobilization of metallic particles with the increase in crosslinking of PEG. Nitrate removal efficiency increases too.

Esthetic improvements through systematic diagnosis and treatment procedures in patients with unesthetic maxillary anterior teeth proportion after orthodontic treatment: Case report (교정치료 후 비심미적인 상악 전치부 비율을 가진 환자에서 체계적인 진단 및 치료과정을 통해 심미성이 개선된 보철 수복 증례)

  • Lee, Seong-Min;Choi, Yu-Sung
    • The Journal of Korean Academy of Prosthodontics
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    • v.53 no.3
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    • pp.262-275
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    • 2015
  • The treatment of areas demanding esthetic requirements, such as maxillary anterior teeth, should take into account the achievement of a healthy, harmonious to the surrounding tissue, and an attractive smile line. In this case report, smile line, soft tissue and hard tissue morphology, and the anatomy and proportion of the tooth, must be considered. In patients with unesthetic maxillary anterior ratio due to inadequate gingival contour and diastema caused by peg lateralis, it would be challenging to achieve an esthetic restoration by orthodontic treatment alone. In such case, after orthodontic treatment, dento-gingivo-facial compositional diagnosis and analysis, followed by gingivectomy and prosthodontic restoration is needed to improve the interdental mesial/distal, width/length ratio to achieve a satisfactory esthetic result. In addition, when improving the tooth proportion of peg lateralis by prosthodontic treatment, Porcelain laminate veneer (PLV), which results in less tooth structure loss, reproduction of similar shade to that of the proximal tooth and high transparency, is recommended. This case report demonstrates esthetic improvements by prosthodontic restoration through systematic diagnosis and treatment procedure in patients with unesthetic maxillary anterior proportion after orthodontic treatment due to peg lateralis by means of two female patients aged twenty years old.

Studies on the Improvement and Management of Hill Pasture (산지초지 개량과 관리에 관한 연구)

  • ;David Leung
    • Journal of The Korean Society of Grassland and Forage Science
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    • v.17 no.4
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    • pp.329-344
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    • 1997
  • To improve germination and growth of forages of hill pasture seeds of several forages were osmotically primed with polyethylene glycol (PEG) under different PEG concentrations, treatment periods, and temperatures. Seeds were coated with several materials, and tested for germination. The best primed or coated seeds in germination tests were surface sow on hilly area. The results obtained are summarized as follows; 1. Osmotic priming with PEG accelerated germination of forages and reduced time taken for germination. 2. Germinability was best when the seeds of Tama ryegrass or orchardgrass were treated for 6-9 days at 30g PEG1100 ml water, red clover or white clover for 3, or 9 days in 20g PEG1100 ml water at $10^{\circ}C$. 3. Priming seeds of Tama ryegrass or orchardgrass in 30% PEG solution for 6 days, and seeds of red clover or white clover in 20% PEG solution for 6 days at $15^{\circ}C$ were most effective in germination, similar to priming at $10^{\circ}C$ . 4. Priming seeds of Tama ryegrass at 15C, and orchardgrass, red clover, or white clover at $10^{\circ}C$ were effective in germination than priming at other temperatures. 5. Osmotic priming with PEG accelerated germination of forages compared to coated seeds in Petri-dishes, while coated seeds germinated more slowly, but showed better emergence and superior growth to those of primed or intact seeds in the field. 6. Priming seeds increased yield slightly, and coating seeds significantly increased its yield on hilly area.

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Conditions for Intergeneric Protoplast Fusion of Yeast (효모의 이속간 원형질체 융합조건)

  • Kim, Young-Ho;Seu, Jung-Hwn
    • Microbiology and Biotechnology Letters
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    • v.13 no.4
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    • pp.383-389
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    • 1985
  • Optimum conditions of PEG treatment for the intergeneric fusion of yeast protoplasts were investigated. Fusants were selected by nutritional complementation on minimal medium. The intergeneric fusion frequency between pro-toplasts of S. cerevisiae and C. tropicalis was distributed 10$^{-4}$ to 10$^{-6}$, depending on the combination of parental strains. PEG 4000 or 6000 are equally effective. 30%(w/v) PEG 4000 was found to be optimum and below 20% its stabilizing effect was lost, resulting in protoplast lysis, and optimum pH was 8.0. The efficiency of PEG was enhanced by higher temperature of the PEG solution, and by the addition of Ca ions. The stimulating effect of Ca ions in the range of 1 mM to 100 mM proved similar.

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