Synthesis of Oximes in the Microwave Oven

1992 ◽  
Vol 57 (11) ◽  
pp. 2407-2412 ◽  
Author(s):  
Monika Puciová ◽  
Štefan Toma
Keyword(s):  
Microwave Heating ◽  
Reaction Rate ◽  
Microwave Oven ◽  
Effect Of Solvents

The synthesis of a broad range of oximes has been studied. It was found that the application of microwave heating enhanced dramatically the reaction rate, and practically quantitative yields of oximes were isolated after less than 1-min heating in the most cases. The effect of solvents on the course of the reaction was also studied.

Microwave Nitrudation of Silicon Compacts Utilizing a Temperature Gradient

1992 ◽  
Vol 287 ◽  
Author(s):  
Jeffrey J. Thomas ◽  
Hamlin M. Jennings ◽  
D. Lynn Johnson
Keyword(s):  
Silicon Nitride ◽  
Temperature Gradient ◽  
Microwave Heating ◽  
Reaction Rate ◽  
Nitrogen Depletion

ABSTRACTSilicon compacts nitrided utilizing the temperature gradient inherent to microwave heating were more fully converted to silicon nitride than was possible with similar compacts nitrided isothermally. Although nitrogen depletion prevented the reaction rate in the center from exceeding that at the surface, the temperature gradient partially counteracted the effect of nitrogen depletion. Thus the microwave-heated specimens could be nitrided fully before the reduction in porosity that accompanies the reaction eliminated the diffusion of nitrogen into the compact.

scholarly journals Otimização da produção de biodiesel a partir de óleo de coco babaçu com aquecimento por microondas

2018 ◽  
Vol 39 (4) ◽  
pp. 37
Author(s):  
Ulisses Magalhães Nascimento ◽  
Antonio Carlos Sales Vasconcelos ◽  
Eduardo Bessa Azevedo ◽  
Fernando Carvalho Silva
Keyword(s):  
Microwave Heating ◽  
Irradiation Time ◽  
Reaction Times ◽  
Coconut Oil ◽  
Microwave Oven ◽  
Raw Material ◽  
Biodiesel Production ◽  
Experimental Conditions ◽  
Domestic Microwave Oven ◽  
Central Composite

Reactions under microwave heating present reduced reaction times and larger yields. Therefore, this work is aimed at adapting a domestic microwave oven and optimizing the transesterification reaction used in biodiesel production with microwave heating, using babaçu coconut oil as raw material. It was used a central composite design for varying irradiation time, KOH concentration, and oil:methanol ratio. Statistical analyses were performed in orderto assess the significance of the model used. The optimized experimental conditions were: oil:methanol ratio, 8.59; KOH concentration, 2.19 %; and irradiation time, 70 seconds, givingan yield of approximately 100% regarding esters formation.

scholarly journals Microwave Assisted Synthesis of Indole Substituted Alkenes Using Knoevenagel Condensation Reaction and their Antibacterial Activity Study

2010 ◽  
Vol 7 (s1) ◽  
pp. S543-S551 ◽  
Author(s):  
Shubha Jain ◽  
B. Nagi Reddy ◽  
K. Sambasiva Rao ◽  
G. Neeliah
Keyword(s):  
Antibacterial Activity ◽  
Reaction Rate ◽  
Knoevenagel Condensation ◽  
Condensation Reaction ◽  
Microwave Oven ◽  
Microwave Assisted Synthesis ◽  
Microwave Assisted ◽  
Knoevenagel Condensation Reaction ◽  
New Compounds ◽  
Active Methylene

The reaction rate of Knoevenagel condensation can be dramatically enhanced by irradiating the reaction mixture containing an aldehyde, active methylene compound,L-proline and chlorobenzene with a commercial microwave oven. Twenty Knoevenagel condensation products were synthesized within 5-17 min in good yields. The new compounds were also screened for their antibacterial activity.

Nitridation of Non-Isothermal Silicon Compacts

1992 ◽  
Vol 269 ◽  
Author(s):  
Jeffrey J. Thomas ◽  
Renee R. Jesse ◽  
D. Lynn Johnson ◽  
Hamlin M. Jennings
Keyword(s):  
Silicon Nitride ◽  
Temperature Gradient ◽  
Microwave Heating ◽  
Reaction Rate ◽  
Conventional Heating

ABSTRACTThe use of microwave heating for the processing of reaction-bonded silicon nitride offers at least two advantages over conventional heating methods. First, the reaction can be made to proceed preferentially in the interior of the reacting compact by maximizing the temperature gradient resulting from microwave heating. This helps maintain the flow of nitrogen into the compact during the later stages of the reaction, when the overall porosity is reduced. Second, the reaction rate can be controlled by changing the power, which gives better control over the processing than can be obtained using conventional heating.

scholarly journals The effect of microwave heating on the optical characteristics of berry extracts

2019 ◽  
Vol 81 (1) ◽  
pp. 218-224
Author(s):  
L. P. Nilova ◽  
R. A. Ikramov ◽  
S. M. Malyutenkova
Keyword(s):  
Microwave Heating ◽  
Wavelength Range ◽  
Microwave Oven ◽  
Hot Water ◽  
Optical Characteristics ◽  
Color Intensity ◽  
Generation Frequency ◽  
Color Coordinates ◽  
Microwave Effect ◽  
Berry Extracts

The paper presents the optical characteristics of extracts obtained from marc berries of the heather family - lingonberries, cranberries, blueberries and blueberries. To obtain extracts, the berries were pressed by electromechanical method. From the obtained marc berries, water extracts were obtained in a microwave oven with a power of 800 W and a generation frequency of 2450 MHz for different exposure modes from 288 W to 800 W. Hydraulic module 1:10. The duration of the microwave heating 60 seconds. Controls were extracts obtained using hot water and infusion for 10 minutes. The optical characteristics of the juices and extracts from the marc berries were measured spectrophotometrically in the wavelength range of 410-630 nm. The maximum values of the optical spectra were recorded at D520, regardless of the berries used. An increase in the power of the microwave effect led to an increase in the optical values of the spectra of the extracts: bilberry > blueberry> lingonberry> cranberry. The optical characteristics of microwave extracts reached control values when exposed to 464 W for bilberries and blueberries, 648 W for lingonberries and 800 W for cranberries, which affected the color intensity and color coordinates, but did not significantly affect the shade, with the exception of bilberries. The color coordinates of bilberry extracts were closest to the color coordinates of the juices, the hue was more intense than in the juices, but was within the limits characteristic of the formation of color under the influence of anthocyanins. Bilberry extracts had a higher color intensity than blueberry extracts, but smaller shade values. Optical characteristics of berry extracts can be used to optimize the hydronic module and extraction modes.

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