• 제목/요약/키워드: PEG treatment

검색결과 289건 처리시간 0.024초

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

  • 허삼남
    • 한국초지조사료학회지
    • /
    • 제10권3호
    • /
    • pp.121-128
    • /
    • 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.

  • PDF

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

  • 유건상;최종하;최진환
    • 한국환경과학회지
    • /
    • 제20권11호
    • /
    • pp.1499-1507
    • /
    • 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.

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

  • 임기표;조종수;김익주;나은선
    • Journal of the Korean Wood Science and Technology
    • /
    • 제23권4호
    • /
    • pp.1-9
    • /
    • 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.

  • PDF

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
    • /
    • 제24권2호
    • /
    • pp.230-237
    • /
    • 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.

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

  • 김수철;이광희
    • 박물관보존과학
    • /
    • 제14권
    • /
    • pp.7-12
    • /
    • 2013
  • 창녕 비봉리에서 출토된 신석기 시대 나무배 편을 대상으로 PEG 함침처리 후 조습건조를 진행하였다. 칠기나 목기와 같은 소형 수침고목재 유물의 경우에는 진공동결건조법이 가장 많이 적용되고 있으나, 소형 유물에만 적용할 수 있다는 단점이 있다. 따라서 선박과 같은 대형유물의 경우에는 대부분 PEG 처리 후 자연건조를 하고 있으나 장시간의 약제함침이 요구되며, 건조결함이 발생할 위험이 있다. 따라서 본 처리에서는 비봉리 출토 나무배 편 4점을 대상으로 PEG 수용액으로 10%에서 80%까지 단계적으로 함침처리 후 조습건조법을 적용하였다. 또한 조습건조 후 배편의 습도조건별 중량변화를 측정하여 유물의 치수안정성을 확인하였다.

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

  • 김수철
    • 보존과학회지
    • /
    • 제28권2호
    • /
    • pp.95-99
    • /
    • 2012
  • 처리 농도 및 용매에 따른 PEG의 압축강도를 측정하고 치수안정화 효과와 비교 하여 전시 및 보관에 적합한 처리 조건을 설정하고자 하였다. 선행된 고함수율 수침고목재의 동결건조를 위한 PEG전처리 농도 및 용매 설정 연구에서 수용액 PEG 40% 전처리 후 진공동결건조가 치수안정성이 가장 우수하게 나왔다. 이번 연구에서는 약품의 처리 농도에 비례하여 압축강도가 증가하였으며, 용매에 있어서는 물이 t-butanol 보다 상대적으로 압축강도가 높게 나타났다. 특히 수용액에서 PEG 40%와 PEG 50%의 강도차가 6.6%(16kgf/$cm^2$)로 큰 차이가 없는 것으로 나타났다. 이상의 결과에 따라 수침고목재유물의 보존처리에서 치수안정성과 압축강도를 동시에 충족시키고자 할 때, 수용액 PEG 40% 전처리 후 동결건조를 실시하는 것이 가장 효과적인 것으로 확인되었다.

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
    • /
    • 제9권1호
    • /
    • pp.1-7
    • /
    • 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.

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

  • 이성민;최유성
    • 대한치과보철학회지
    • /
    • 제53권3호
    • /
    • pp.262-275
    • /
    • 2015
  • 상악 전치부와 같은 심미성이 요구되는 부위의 치료 시에는 건강하고, 주위조직과 조화를 이루며 매력적인 미소선의 형성을 염두에 두어야 한다. 이에 관하여 미소선, 연조직 및 경조직의 형태뿐 아니라 치아의 해부학적 형태와 비율 또한 고려하여야 한다. 상악 측절치의 왜소치(peg lateralis)로 인한 치간이개 및 부적절한 치은 형태로 인해 비심미적인 상악 전치부 비율을 가진 환자에서는 교정치료만으로 심미적 수복이 이루어지기 힘들 수 있다. 이런 경우, 교정치료가 끝난 이후 치아-치은-안면 구도에서의 진단 및 분석을 통한 치은절제술 및 보철적 수복을 통해 치아간의 근/원심, 폭/길이 비율을 개선시켜야 심미적으로 만족할 만한 결과를 얻어낼 수 있다. 또한, 상악 측절치의 왜소치(peg lateralis) 치아 비율 개선을 위한 보철물 제작 시 치질삭제가 적으며 인접치와 유사한 색조가 재현 가능하고 투명도가 높은 도재 라미네이트 비니어(Porcelain laminate veneer, PLV)가 선호되고 있다. 본 증례에서는 두 명의 20세 여자 환자로 교정치료 후 상악 측절치의 왜소치로 인한 치간이개 및 부적절한 치은 형태로 인해 비심미적인 상악 전치부 비율을 가진 환자에서의 체계적인 진단 및 치료과정을 통해 심미성이 개선된 보철 수복 증례를 보고하고자 한다.

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

  • 허삼남
    • 한국초지조사료학회지
    • /
    • 제17권4호
    • /
    • pp.329-344
    • /
    • 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.

  • PDF

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

  • Kim, Young-Ho;Seu, Jung-Hwn
    • 한국미생물·생명공학회지
    • /
    • 제13권4호
    • /
    • pp.383-389
    • /
    • 1985
  • 전분을 발효할 수 있는 새로울 효모균수의 개발을 목적으로 PEG를 fusogen으로 사용하여 이속 효모간 원형질체 융합을 시도하였다. 원형질체 융합에 사용한 친균주의 genetic marker로는 상보적 영양요구성을 이용하였고 각각의 영양요구성이 상호보완되어 최소배지상에 자라는 colony를 융합체로하였다. S. cerevisiae와 C. tropicalis의 이속간 원형질체의 융합빈도는 $10^{-4}$에서 $10^{-6}$ 정도였으며, 원형질체 융합에 있어서 PEG 4,000. 30%가 가장 좋은 효과를 나타내었다. 최적 pH는 8.0이었으며, PEG의 처리효과는 온도가 상승함에 따라 증가하여 35$^{\circ}C$에서 최적을 나타내었고 또한 Ca이온의 첨가에 의해서도 증가하였는데 Ca 이온의 촉진효과는 1mM과 100mM 농도 사이에서 최고를 나타내었다.

  • PDF