Rapid microwave synthesis of Pb5(VO4)3X (X = F, Cl, Br and I) vanadinite apatites for the immobilisation of halide radioisotopes.

2012 ◽  
Vol 1475 ◽  
Author(s):  
Martin C. Stennett ◽  
Ian J. Pinnock ◽  
Neil C. Hyatt
Keyword(s):  
Single Phase ◽  
Rapid Heating ◽  
Microwave Oven ◽  
Dielectric Heating ◽  
Muffle Furnace ◽  
Domestic Microwave Oven ◽  
Microwave Dielectric ◽  
Microwave Dielectric Heating ◽  
Profile Characteristic ◽  
Rapid Heating Rate

ABSTRACTMicrowave dielectric heating was utilized to synthesize potential host phases for halide radioisotopes. Synthesis of Pb5(VO4)3I was successfully achieved, without the use of a sealed container, using a modified domestic microwave oven (DMO) operating at 2.45 GHz. Rapid synthesis of Pb5(VO4)3X (X = F, Cl, Br) was also achieved using a commercially available microwave muffle furnace, also operating at 2.45 GHz. The combination of rapid heating rate and inverse temperature profile characteristic of microwave heating was found to promote formation of the target phases whilst retarding the volatilization of the halide species. Pb5(VO4)3I ceramic bodies produced in the DMO exhibited a heterogeneous zoned microstructure, whereas Pb5(VO4)3X phases with X = F, Cl, and Br fabricated in the microwave muffle furnace were dimensionally uniform suggesting this could be a promising route to fabricating single phase, dense halide containing ceramics.

scholarly journals Synthesis of 2-Substitued Indoles via Pd-Catalysed Cyclization in an Aqueous Micellar Medium

Molecules ◽  
2021 ◽  
Vol 26 (13) ◽  
pp. 3917
Author(s):  
Sofia Siciliano ◽  
Elena Cini ◽  
Maurizio Taddei ◽  
Giorgia Vinciarelli
Keyword(s):  
Water Environment ◽  
Delivery Mode ◽  
Micellar Medium ◽  
Dielectric Heating ◽  
Microwave Dielectric ◽  
Microwave Dielectric Heating ◽  
Heating Mode ◽  
Aqueous Micellar Medium ◽  
By Products ◽  
Better Than

The synthesis of 2-substituted indoles starting from the corresponding unprotected 2-alkynylanilines was made possible in 3% TPGS-750-M water using Pd(OAc)2 alone as the catalyst. The reaction was sensitive to the heating mode respect to the nature of the starting material as, in many cases, convectional heating was better than microwave dielectric heating. The MW (microwave) delivery mode had also an influence in the formation of by-products and, consequently, product yields. A tandem Sonogashira-cyclisation reaction was also accomplished using Pd(OAc)2/Xphos in the nanomicellar water environment.

Synthesis of Diaryl Ethers, Diaryl Sulfides, Heteroaryl Ethers and Heteroaryl Sulfides under Microwave Dielectric Heating.

ChemInform ◽  
2005 ◽  
Vol 36 (43) ◽  
Author(s):  
Feng Li ◽  
Qingqing Meng ◽  
Huansheng Chen ◽  
Zhiming Li ◽  
Quanrui Wang ◽  
...  
Keyword(s):  
Dielectric Heating ◽  
Diaryl Ethers ◽  
Microwave Dielectric ◽  
Microwave Dielectric Heating

Increasing Legume Seed Germination by VHF and Microwave Dielectric Heating

1976 ◽  
Vol 19 (2) ◽  
pp. 0369-0371 ◽  
Author(s):  
S. O. Nelson ◽  
L.A. T. Ballard ◽  
L. E. Stetson ◽  
T. Buchwald
Keyword(s):  
Seed Germination ◽  
Dielectric Heating ◽  
Legume Seed ◽  
Microwave Dielectric ◽  
Microwave Dielectric Heating

scholarly journals Dielektrické vlastnosti zemědělských produktů a některé jejich aplikace

2008 ◽  
Vol 54 (No. 2) ◽  
pp. 104-112 ◽  
Author(s):  
S.O Nelson
Keyword(s):  
Dielectric Properties ◽  
Moisture Content ◽  
Radio Frequency ◽  
Fruits And Vegetables ◽  
Agricultural Products ◽  
Dielectric Heating ◽  
Quality Factors ◽  
Poultry Products ◽  
Microwave Dielectric ◽  
Microwave Dielectric Heating

The use of dielectric properties of agricultural products for sensing moisture in grain and seed and their application in radio-frequency and microwave dielectric heating is discussed briefly. Values for the dielectric properties of a number of products, including grain and seed, fruits and vegetables, and poultry products, are presented graphically to show the dependence of these properties on frequency, moisture content, and temperature. The potential for using the dielectric properties to sense quality factors other than moisture content is also considered.

scholarly journals An Improved Method for the Quaternization of Nicotinamide and Antifungal Activities of Its Derivatives

Molecules ◽  
2019 ◽  
Vol 24 (6) ◽  
pp. 1001 ◽  
Author(s):  
Tamara Siber ◽  
Valentina Bušić ◽  
Dora Zobundžija ◽  
Sunčica Roca ◽  
Dražen Vikić-Topić ◽  
...  
Keyword(s):  
Fusarium Culmorum ◽  
13C Nmr Spectroscopy ◽  
Macrophomina Phaseolina ◽  
Dielectric Heating ◽  
Improved Method ◽  
Mycelium Growth ◽  
1H And 13C Nmr ◽  
Antifungal Activities ◽  
Microwave Dielectric ◽  
Microwave Dielectric Heating

The quaternization reactions of nicotinamide, with different electrophiles: methyl iodide and substituted 2-bromoacetophenones (4-Cl, 4-Br, 4-H, 4-CH3, 4-F, 4-OCH3, 4-Ph, 2-OCH3, 4-NO2) are reported. The preparations were carried out by conventional synthesis and under microwave irradiation in absolute ethanol and acetone. The synthesis performed by microwave dielectric heating significantly improved yield, up to 8 times, and shortened down the reaction time from ca. one day in conventional, to 10–20 min. The structures of the synthesized compounds were confirmed by IR, 1H- and 13C-NMR spectroscopy, mass spectrometry and elemental analysis. The compounds have been screened for antifungal activities against Fusarium oxysporum, Fusarium culmorum, Macrophomina phaseolina and Sclerotinia sclerotiorum at concentrations of 10 µg/mL and 100 µg/mL. Six compounds showed the strong inhibition of mycelium growth at a concentration of 10 µg/mL. All tested compounds revealed the great inhibitory activities against S. sclerotiorum at a concentration of 100 µg/mL.

Sign in / Sign up

Export Citation Format

Share Document