• Title/Summary/Keyword: microwave irradiation method

Search Result 75, Processing Time 0.023 seconds

Microwave Irradiation-assisted RNA Extraction from Woody Tissues for Plant Virus Detection

  • Duong, Thanh Van;Shin, Dong-Il;Park, Hee-Sung
    • The Plant Pathology Journal
    • /
    • v.26 no.3
    • /
    • pp.286-288
    • /
    • 2010
  • Plant tissue homogenization using a mortar or mechanical equipment has been the preferred method for obtaining high yields of total RNA; this method, however, is both time-consuming and expensive. Additionally, homogenization may generate excessive endogenous RNases, polyphenolics, and other substances that reduce the quality and quantity of RNA. In this study, we describe the microwave irradiation-assisted RNA extraction (MIRE) technique which, without tissue disruption and homogenization, allows for the cost-effective and rapid generation of intact RNA from apple cane shavings and the reliable detection of apple virus by RT-PCR.

Microwave Irradiation, A New Processing Method of Aconiti Tuber (마이크로파를 이용한 부자의 새로운 수치방법)

  • Yun-Choi, Hye-Sook;Yoo, Kyung-Sook;Lee, Sook-Youn;Lee, Youn-Hee;Kwak, Wie-Jong;Kim, Ki-Hyup
    • Korean Journal of Pharmacognosy
    • /
    • v.21 no.4
    • /
    • pp.284-289
    • /
    • 1990
  • Crude Aconiti Tubers were irradiated with microwave for 5 or 10 min with or without $NaHCO_3$. Ten min-irradiation reduced the contents of aconitine and mesaconitine to the level of those of commercially available processed Aconiti tuber power which is prepared with the high pressure-high temperature technique. The contents of benzoylaconine of the 10 min-irradiated Aconiti tubers were also comparable to those of commerciallized processed Aconiti tuber powder. However, irradiation with 1% $NaHCO_3$ soln. resulted in the drastic reduction of all the three above alkaloids.

  • PDF

Synthesis and Study of Pt/MWCNTs Catalysts by Using Microwave Assisted Polyol Method for PEM Fuel Cells (마이크로파-폴리올법을 이용한 고분자 전해질 연료전지용 Pt/MWCNTs 촉매의 제조 및 이의 특성분석)

  • Lee, Tae Kyu;Hur, Seung Hyun
    • Journal of the Korean Electrochemical Society
    • /
    • v.15 no.4
    • /
    • pp.264-269
    • /
    • 2012
  • In this study, highly loaded(50 wt%) and very stable Pt/MWCNT catalysts for Polymer Electrolyte Membrane Fuel Cells(PEMFCs) are synthesized in short time scale by microwave assisted polyol method with different microwave irradiation time. The XRD and TEM results show that the Pt size becomes bigger as the microwave irradiation time increases. The mean Pt sizes of fabricated catalysts are 4.1, 4.9 and 8.5 nm when the microwave are irradiated for 10, 20 and 30 min, respectively. When compared with Pt catalyst made by conventional polyol method, it shows better long term durability due to the better Pt dispersion on the MWCNT surface.

Microwave-Assisted and Conventional Synthesis of Benzothieno [3,2-e] [1,3,4] triazolo[4,3-c]pyrimidines: A Comparative Study

  • Gaonkar, Santhosh L.;Ahn, Chuljin;Princia, Princia;Shetty, Nitinkumar S.
    • Journal of the Korean Chemical Society
    • /
    • v.58 no.4
    • /
    • pp.388-392
    • /
    • 2014
  • Benzothieno[2,3-d]pyrimidines (2,3,4) and benzothieno[3,2-e][1,3,4]triazolo[4,3-c] pyrimidines (5a-c) were synthesized from the precursor 2-amino-7-oxo-4,5,6,7-tetrahydro-1-benzothiophene-3-carbonitrile 1 by employing the conventional method as well as the microwave irradiation technique. The precursor 2-amino-3-cyanothiophene analogue 1 was synthesized by employing the well-known Gewald reaction. In the present work it has been found that the microwave supported syntheses are more efficient than the conventional classical heating methods. The structures of all the compounds were ascertained by spectral and analytical data.

Optimization of PCR Condition with Conidiospore for Primary Screening of Aspergillus nidulans Transformants (Aspergillus nidulans의 무성포자를 이용한 PCR 조건의 최적화)

  • 박희문;박범찬;박윤희;양소영
    • Korean Journal of Microbiology
    • /
    • v.38 no.2
    • /
    • pp.103-106
    • /
    • 2002
  • Direct PCR from intact fungal cells is not readily suitable to all fungi mainly because of difficulties in rupturing the cell walls. Microwave irradiation has been proven to be useful in fungal DNA extraction protocol. Here we describe a fast template preparation method for PCR amplification from Aspefillus nidulans conidiospores using microwave irradiation. We optimized the duration far microwave irradiation, and the amount of template DNA for PCR. Amplification from samples prepared in this manner was so efficient that we could get PCR products with size enough to identify transformants. We believe that this is a time-saving procedure for screening true transformants of A. nidulans.

One-Pot Efficient Beckmann Rearrangement of Ketones Catalyzed by Silica Sulfuric Acid (황산-실리카에 의해 촉진된 Ketone의 효율적인 One-Pot 베크만 자리옮김 반응)

  • Eshghi, H.;Hassankhani, A.
    • Journal of the Korean Chemical Society
    • /
    • v.51 no.4
    • /
    • pp.361-364
    • /
    • 2007
  • A one-pot Beckmann rearrangement for the preparation of amides from ketones is described using the silica sulfuric acid under Microwave irradiation. Advantages of this method are regioselectivity with high yields in a simple operation and short reaction time, in which the mole ratio of acid and ketone was 1:2 and it should be greener than the currently used systems.

Microwave-Assisted Synthesis of 3-Styrylchromones in Alkaline Ionic Liquid

  • Shelke, Kiran F.;Sapkal, Suryakant B.;Shitole, Nana V.;Shingate, Bapurao B.;Shingare, Murlidhar S.
    • Bulletin of the Korean Chemical Society
    • /
    • v.30 no.12
    • /
    • pp.2883-2886
    • /
    • 2009
  • A simple, highly efficient and environmentally benign method for the synthesis of 3-styrylchromones from 3-formylchromones and 4-nitrophenylacetic acid/4-nitrotolune in the presence of catalytic amount of basic ionic liquid 1-butyl-3-methylimidazolium hydroxide [(bmim)OH] carried out under the influence of microwave irradiation. This method gives remarkable advantages such as, short reaction times, simple work-up procedure and moderate to good yields. The ionic liquid was successfully reused for four cycles without significant loss of activity.

Microwave-Assisted Solvent and Catalyst Free Synthesis of 2H-Pyrans

  • Edayadulla, Naushad;Lee, Yong Rok
    • Bulletin of the Korean Chemical Society
    • /
    • v.34 no.10
    • /
    • pp.2963-2967
    • /
    • 2013
  • This paper describes a simple and efficient method involving domino Knovenegal/$6{\pi}$ electrocyclization for the preparation of a variety of 2H-pyrans using microwave irradiation under solvent- and catalyst-free conditions. This method offers the advantages of a green approach, high yields, and short reaction times. Sixteen compounds (9a-p) were obtained in good to excellent yields using the procedure.

Comparative Evaluation of Solution Processed InZnO Junctionless Thin-Film Transistors in Different Post-Treatment Method

  • Park, Jeong-Hun;An, Min-Ju;Jo, Won-Ju
    • Proceedings of the Korean Vacuum Society Conference
    • /
    • 2014.02a
    • /
    • pp.347.1-347.1
    • /
    • 2014
  • 최근, 박막 트랜지스터는 빠른 동작 속도, 낮은 공정비용 그리고 저온공정 등의 특성을 필요로 하고 있다. 그 중 indium-zinc oxide (InZnO)는 높은 전기적 특성, 높은 광 투과도 그리고 우수한 안정성 때문에 기존의 반도체를 대체할 수 있을 것으로 기대된다. InZnO의 경우 indium과 zinc의 조성비에 따라 특성 변화의 차이가 크기 때문에 다양한 조성비에 대한 연구가 보고되고 있는데, 기존의 InZnO 박막을 증착하는 방법의 경우에 조성비의 변화 과정에 많은 공정상의 어려움이 있다. 이 같은 문제점 때문에 조성비의 변화를 용이하게 할 수 있는 용액공정을 이용한 연구가 진행되고 있다. 또한 용액공정은 높은 균일성, 공정 시간 및 비용 감소 그리고 대면적화가 가능한 장점을 가지고 있다. 한편, 용액공정을 기반으로 한 InZnO의 경우에 용액 상태에서 고체 상태의 순수한 금속 산화물 상태로 바꾸기 위해 post-treatment 가 필요하다. 일반적으로 furnace 열처리 방법을 사용하는데, 이 경우 낮은 열효율 및 고비용 등의 문제점을 가지고 있다. 특히 glass 또는 flexible 기판의 경우 열처리 온도에 대한 제약이 있다. 이러한 문제를 해결하기 위한 방법으로 최근에 microwave irradiation를 이용한 저온 post-treatment 방법이 보고되고 있다. Microwave irradiation는 짧은 공정시간 및 열 균일성 등의 장점이 있다. 따라서 본 연구에서는 다양한 indium과 zinc의 조성비를 갖는 용액을 제작한 후 spin coating을 이용하여 증착한 InZnO 기반의 박막 트랜지스터를 제작하였다. Furnace와 microwave 방식으로 post-treatment 하여 비교 평가한 결과 microwave irradiation 한 경우 furnace 열처리 한 경우 보다 더 안정된 동작 전압을 가지는 것으로 나타났다. 따라서 저온공정이 가능한 microwave irradiation 방법으로 post-treatment 한다면 차세대 산화물 반도체로서의 적용이 가능할 것으로 기대된다.

  • PDF

Fabrication and Characterization of Ag-coated BCP Scaffold Derived from Sponge Replica Process (스폰지 복제법을 이용한 Ag 코팅 BCP 지지체의 제조 및 평가)

  • Kim, Min-Sung;Kim, Young-Hee;Song, Ho-Yeon;Min, Young-Ki;Lee, Byong-Taek
    • Korean Journal of Materials Research
    • /
    • v.20 no.8
    • /
    • pp.418-422
    • /
    • 2010
  • As a starting material, BCP (biphasic calcium phosphate) nano powder was synthesized by a hydrothermal microwave-assisted process. A highly porous BCP scaffold was fabricated by the sponge replica method using 60 ppi (pore per inch) of polyurethane sponge. The BCP scaffold had interconnected pores ranging from $100\;{\mu}m$ to $1000\;{\mu}m$, which were similar to natural cancellous bone. To realize the antibacterial property, a microwave-assisted nano Ag spot coating process was used. The morphology and distribution of nano Ag particles were different depending on the coating conditions, such as concentration of the $AgNO_3$ solution, microwave irradiation times, etc. With an increased microwave irradiation time, the amount of coated nano Ag particles increased. The surface of the BCP scaffold was totally covered with nano Ag particles homogeneously at 20 seconds of microwave irradiation time when 0.6 g of $AgNO_3$ was used. With an increased amount of $AgNO_3$ and irradiation time, the size of the coated particles increased. Antibacterial activities of the solution extracted from the Ag-coated BCP scaffold were examined against gram-negative (Escherichia coli) and gram-positive bacteria (Staphylococcus aureus). When 0.6 g of $AgNO_3$ was used for coating the Ag-coated scaffold, it showed higher antibacterial activities than that of the Ag-coated scaffold using 0.8 g of $AgNO_3$.