A Fast Synthesis and Sintering of Mg2Si1−xSnx (0≤x≤1.0) Solid Solutions by Microwave Irradiation

2011 ◽  
Vol 197-198 ◽  
pp. 417-420 ◽  
Author(s):  
Shu Cai Zhou ◽  
Chen Guang Bai ◽  
Chun Lin Fu
Keyword(s):  
Microwave Irradiation ◽  
Solid Solutions ◽  
Microwave Assisted Synthesis ◽  
Green Density ◽  
X Ray Diffraction ◽  
Power Setting ◽  
Xrd Patterns ◽  
Heating Behavior ◽  
Fast Synthesis ◽  
Lower Heating

In order to reduce the oxidizing and volatilizing caused by Mg element in the traditional methods for synthesizing Mg2Sil-xSnxsolid solutions, Mg2Sil-xSnxsolid solutions have been prepared by Microwave-assisted Synthesis techniques. The heating behavior of Mg, Si and Sn fixed powder was investigated under microwave irradiation. X-ray diffraction (XRD) was used to characterize the powders. The results suggest that the temperature-rising rate is also dependent on the initial green density and higher green density provides lower heating rate while power setting are fixed. XRD patterns show that Mg2Sil-xSnxsolid solutions have been well formed under microwave irradiation.

scholarly journals Accelerated syntheses of amine-bis(phenol) ligands in polyethylene glycol or “on water” under microwave irradiation

2008 ◽  
Vol 86 (5) ◽  
pp. 435-443 ◽  
Author(s):  
Francesca M Kerton ◽  
Stacey Holloway ◽  
Angela Power ◽  
R Graeme Soper ◽  
Kristina Sheridan ◽  
...  
Keyword(s):  
Polyethylene Glycol ◽  
Microwave Irradiation ◽  
Hydrophobic Effect ◽  
High Yield ◽  
Microwave Assisted Synthesis ◽  
X Ray Diffraction ◽  
X Ray ◽  
Microwave Assisted ◽  
Mannich Condensation ◽  
Time And Energy

Pure amine-bis(phenol) ligands are readily accessible in high yield, often >90%, when the Mannich condensation reactions are performed “on water” or in poly(ethyleneglycol) (PEG). Microwave-assisted synthesis dramatically reduces the time and energy required to prepare these molecules, typically from 24 h to 5 min. The approach seems to be widely applicable (7 amines and 5 phenols were tested to yield a diverse set of bis(phenol) ligands). Significant improvements in yield were observed for ligands derived from di-tert-amyl and di-tert-butyl phenols, possibly resulting from a hydrophobic effect. Single crystal X-ray diffraction data for the ligand derived from p-cresol and N,N′-dimethylethylenediamine is reported.Key words: amine-phenol, Mannich condensation, on water, microwave, ligand, high-throughput.

scholarly journals MICROWAVE–ASSISTED SYNTHESIS OF MOLYBDENUM DISULFIDE (MoS2)

2018 ◽  
Vol 55 (1B) ◽  
pp. 57
Author(s):  
Nguyen Thi Minh Nguyet
Keyword(s):  
Electron Microscopy ◽  
Microwave Irradiation ◽  
Molybdenum Disulfide ◽  
Low Cost ◽  
Lithium Ion ◽  
Microwave Assisted Synthesis ◽  
X Ray Diffraction ◽  
Heating Rates ◽  
Transmission Electron ◽  
Synthesis Procedure

Molybdenum disulfide (MoS2) nanostructured has been synthesized by a facile and rapid microwave, in which ethylene glycol can act as an excellent susceptor of microwave irradiation. The structure and morphology of MoS2 were characterized by X–ray diffraction (XRD), scanning electron microscopy (SEM) and transmission electron microscopy (TEM). The results show that nanometer scaled (< 100 nm) molybdenum disulfide with different morphologies can be successfully fabricated by microwave liquid–state method. Microwave irradiation can make localized heating that allows higher heating rates and shorter processing time. The low–cost synthesis procedure paves the way for the exploitation of the present product as electrode material in lithium ion batteries (LIBs). 

Reaction Sintering of Mg2Si Intermetallic Compound by Microwave Irradiation

2012 ◽  
Vol 512-515 ◽  
pp. 1683-1686
Author(s):  
Chang Kun Du ◽  
Shu Cai Zhou
Keyword(s):  
Solid State ◽  
Intermetallic Compound ◽  
Microwave Field ◽  
Phase Reaction ◽  
Reaction Sintering ◽  
Green Density ◽  
Power Setting ◽  
Lower Heating Rate ◽  
Lower Heating ◽  
Heating Profile

In order to reduce the oxidizing and volatilizing caused by Mg element in the traditional methods for synthesizing Mg2Si compounds, solid state phase reaction at low temperature was introduced by microwave field. XRD was used to characterize the powders. At the same time, the influences of parameters during the synthesis processing were discussed. The results suggest that the heating profile is also dependent on the initial green density and higher green density provides lower heating rate while power setting are fixed and the oxidation of Mg can be rest rained by changing microwave heating programs. It was found that high purity Mg2Si intermetallic compound can be obtained with excessive content of 8at% Mg from the stoichiometric Mg2Si, 853K and 30min

Luminescence Mechanism of ZnWO4 Nanopowder Synthesized by Microwave-Assisted Heating

2013 ◽  
Vol 470 ◽  
pp. 44-47
Author(s):  
Ming Kwen Tsai ◽  
Yueh Chien Lee ◽  
Chia Chih Huang ◽  
Sheng Yao Hu ◽  
Kwong Kau Tiong ◽  
...  
Keyword(s):  
Microwave Assisted Synthesis ◽  
X Ray Diffraction ◽  
Time Resolved ◽  
X Ray ◽  
Pl Spectra ◽  
Calcination Temperatures ◽  
Microwave Assisted ◽  
Zinc Tungstate ◽  
Xrd Patterns ◽  
Time Resolved Photoluminescence

The luminescence investigations on the calcinated zinc tungstate nanopowder (ZnWO4 NP) synthesized by microwave-assisted synthesis are presented using photoluminescence (PL) and time-resolved photoluminescence (TRPL) analyses. The X-ray diffraction (XRD) patterns exhibit that the significant wolframite structure of ZnWO4 NP can be detected at calcination temperatures above 300 °C. The 12 K PL and TRPL results demonstrated that the deformation of WO6 octahedra is responsible for the low-energy side of PL spectra and dominate the red-shifted PL spectra with increasing calcination temperatures.

Microwave-Assisted Synthesis of Nanocrystalline Zirconium Dioxide Using an Ionic Liquid

2012 ◽  
Vol 271-272 ◽  
pp. 255-258
Author(s):  
Guo Lei Zhang ◽  
Xiu Min Gao ◽  
Xiao Dong Xu
Keyword(s):  
Electron Microscopy ◽  
Ionic Liquid ◽  
Zirconium Dioxide ◽  
Zro2 Nanoparticles ◽  
Microwave Assisted Synthesis ◽  
X Ray Diffraction ◽  
X Ray ◽  
Microwave Assisted ◽  
Infrared Spectrometer ◽  
Xrd Patterns

Zirconium dioxide (ZrO2) nanocrystals were prepared by the microwave-assisted ionic liquid method using an ionic liquid of 1-n-butyl-3-methyl imidazolium tetrafluoroborate ([BMIM]BF4). The X-ray diffraction (XRD) patterns indicated that the crystal structure was monoclinic. The morphology of ZrO2 nanocrystals was characterized by field emission scanning electron microscopy (FESEM) and transimission electron microscopy (TEM), which showed uniform ZrO2 nanoparticles without aggregation. Thermogravimetry (TG) and Fourier transform infrared spectrometer (FTIR) curves confirmed the adsorption of organic compounds on the surface of ZrO2.

scholarly journals Microwave-assisted synthesis, characterization and photoluminescence of shuttle-like BaMoO4 microstructure

2015 ◽  
Vol 33 (3) ◽  
pp. 537-540 ◽  
Author(s):  
Anukorn Phuruangrat ◽  
Budsabong Kuntalue ◽  
Titipun Thongtem ◽  
Somchai Thongtem
Keyword(s):  
Electron Microscopy ◽  
Microwave Assisted Synthesis ◽  
X Ray Diffraction ◽  
X Ray ◽  
Microwave Assisted ◽  
Transmission Electron ◽  
Ft Ir ◽  
Xrd Patterns ◽  
Scanning Electron ◽  
Ft Ir Spectroscopy

Abstract Shuttle-like BaMoO4 microstructure has been successfully synthesized from Ba(N03)2·4H20 and Na2MoO4·2H2O as starting materials in ethylene glycol solvent containing 20 mL 5 M NaOH by microwave radiation at 180 W for 30 min. The as- synthesized BaMoO4 product was characterized by X-ray diffraction (XRD), Fourier transform infrared (FT-IR) spectroscopy, Raman spectrophotometry, scanning electron microscopy (SEM), transmission electron microscopy (TEM) and photolumines­cence (PL) spectroscopy. XRD patterns revealed that the products was tetragonal BaMoO4 phase. SEM and TEM characteriza­tion showed that the product had a shuttle-like BaMoO4 microstructure. PL of the shuttle-like BaMoO4 microstructure showed a maximum emission at 466 nm excited by 280 nm wavelength.

scholarly journals Fast synthesis employing a microwave assisted neat protocol of new monomers potentially useful for the preparation of PDLC films

2011 ◽  
Vol 9 (4) ◽  
pp. 557-566 ◽  
Author(s):  
M. Teresa Barros ◽  
Ana Mouquinho ◽  
Krasimira Petrova ◽  
Mara Saavedra ◽  
João Sotomayor
Keyword(s):  
Optical Properties ◽  
Microwave Irradiation ◽  
Polymer Network ◽  
Reaction Times ◽  
Molecular Chain ◽  
Microwave Assisted Synthesis ◽  
Microwave Assisted ◽  
Fast Synthesis ◽  
Operational Simplicity

AbstractIt has been reported that the length of the molecular chain and the rigidity of molecules influence the structure of the polymer network in PDLC films and hence the electro-optical properties of the composites. Herein, a series of new aromatic monomeric monomethacrylates, bismethacrylates and monovinylbenzene derivatives with a mesogenic core were successfully synthesized under microwave irradiation. The microwave assisted synthesis resulted in decreased reaction times, reduced solvent requirement, increased operational simplicity, and in most cases, improved yields and selectivity.

Microwave-Assisted Synthesis of a Series of Ag/ZnO Nanocomposites and Evaluation of Their Photocatalytic Activities under Multi-Mode Photodegradation

2015 ◽  
Vol 68 (5) ◽  
pp. 774 ◽  
Author(s):  
Li Li ◽  
Xiandan Huang ◽  
Yu Gao ◽  
Wenzhi Zhang ◽  
Xiuli Zhang ◽  
...  
Keyword(s):  
Microwave Irradiation ◽  
Diffuse Reflectance Spectroscopy ◽  
Nitrogen Adsorption ◽  
Microwave Assisted Synthesis ◽  
X Ray Diffraction ◽  
Surface Areas ◽  
Photocatalytic Activities ◽  
Surface Physicochemical Properties ◽  
Adsorption Desorption ◽  
Multi Mode

A series of Ag/ZnO nanocomposites were prepared under microwave irradiation of different powers (100, 200, and 300 W). The crystal structure, morphology, and surface physicochemical properties of the as-synthesized samples were characterized by X-ray diffraction, UV–visible diffuse reflectance spectroscopy, scanning electron microscopy, and nitrogen adsorption–desorption analyses. Compared with the Ag/ZnO prepared by conventional sedimentation process, the crystal structures of Ag and ZnO did not exhibit any transformation after microwave irradiation; however, slight increases or decreases were observed in their absorption spectra and the specific surface areas. Moreover, the morphologies of all Ag/ZnO samples were changed dramatically by microwave irradiation, showing morphologies such as octagonal nano-pyramidal and multi-angled nano-pyramidal. The multi-mode photocatalytic degradation studies showed that the photocatalytic activities of the Ag/ZnO nanocomposites prepared under microwave irradiation of different powers were enhanced to different extents and were much higher than that of P25, ZnO, and Ag/ZnO prepared in the absence of microwave irradiation.

Microwave Mediated Fast Synthesis of Diaminoglyoxime and 3,4-diaminofurazan: Key Synthons for the Synthesis of High Energy Density Materials

2005 ◽  
Vol 2005 (4) ◽  
pp. 245-247 ◽  
Author(s):  
Radhika S Kusurkar ◽  
Shailesh K. Goswami ◽  
Mahadev B. Talawar ◽  
Girish M. Gore ◽  
Shri N. Asthana
Keyword(s):  
Microwave Irradiation ◽  
Hydroxylamine Hydrochloride ◽  
High Energy ◽  
High Energy Density ◽  
Microwave Assisted Synthesis ◽  
One Pot ◽  
Vicarious Nucleophilic Substitution ◽  
Microwave Assisted ◽  
High Energy Density Materials ◽  
Fast Synthesis

This paper reports the first microwave-assisted synthesis of diaminoglyoxime (DAG) and diaminofurazan (DAF). The synthesis involved the vicarious nucleophilic substitution of H of glyoxime using hydroxylamine hydrochloride under microwave irradiation for 2 to 3 min to obtain DAG, which on further irradiation in alkali solution for 20 min yielded DAF. Conversion of glyoxime into DAF was also achieved in a one pot sequence in good overall yield using microwave irradiation.

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