Microwave Assisted Solid State Reaction Synthesis of Complex Amino Acid Complexes of Mn (Ⅱ)

2011 ◽  
Vol 291-294 ◽  
pp. 1331-1334
Author(s):  
Bo Lin Liang ◽  
Na Zhang ◽  
Min Jie Zhou
Keyword(s):  
Amino Acid ◽  
Reaction Time ◽  
Solid State ◽  
Microwave Power ◽  
Irradiation Time ◽  
Reaction Synthesis ◽  
Manganese Ions ◽  
Synthesis Conditions ◽  
Microwave Assisted ◽  
Amino Acid Complexes

Complex amino acid complexes of manganese ions were synthesized using the chelation technology under microwave irradiation. The influences of amount of water, reaction time, microwave power and the molar ration of complex amino acid and manganese on the yield of the synthesized compounds were investigated. Results suggest that optimal synthesis conditions are amount of water, 4 mL, irradiation time, 4 min, microwave power, 500 W, and the molar ration of reactant, 2:1, and the yield of the synthesized compounds was 67.42%.

scholarly journals Extraction of Phytosterol Concentration in Different Legume Pods by Using Microwave-Assisted Hydrodistillation

2019 ◽  
Vol 19 (3) ◽  
pp. 796
Author(s):  
Noormazlinah Noormazlinah ◽  
Norlaili Hashim ◽  
Abdurahman Hamid Nour ◽  
Mimi Sakinah Abdul Munaim ◽  
Maria Pilar Almajano ◽  
...  
Keyword(s):  
Bioactive Compounds ◽  
Microwave Power ◽  
Ethanol Concentration ◽  
Irradiation Time ◽  
Optimal Conditions ◽  
Solvent Concentration ◽  
Visible Spectroscopy ◽  
Optimum System ◽  
Microwave Assisted ◽  
Extraction Parameters

The traditional ways in the extraction of bioactive compounds using conventional methods are disadvantageous from both economic and environmental perspectives. In this, the potential of microwave-assisted hydrodistillation conditions for extraction of phytosterol from legume pods was investigated. Salkowski test performed on the legume pod has shown the reddish brown in all sample which confirmed the presence of phytosterol qualitatively. Liebermann-Burchard procedure and ultraviolet-visible spectroscopy (UV-Vis) apparatus were used to study the concentration of phytosterol at different extraction parameters which are temperature (25–80 °C), solvent concentration (50–100% v/v), irradiation time (1–10 min) and microwave power (400–800 W). The optimal conditions for highest yield of extract (0.219 mg/L) were obtained at a microwave power of 600 W, the irradiation time of 6 min, and ethanol concentration of 75% v/v. Results obtained in this study have shown the capability of microwave-assisted hydrodistillation in the extraction of phytosterol from legume pod. Further works are nevertheless required to provide a deeper understanding of the mechanisms involved to facilitate the development of an optimum system applicable to the industry.

Meso-mechanics simulation analysis of microwave-assisted mineral liberation

2015 ◽  
Author(s):  
Qin Like ◽  
Dai Jun ◽  
Yuan Liqun
Keyword(s):  
Energy Consumption ◽  
Microwave Irradiation ◽  
Power Density ◽  
Microwave Power ◽  
Mineral Content ◽  
Crystal Size ◽  
Irradiation Time ◽  
Mineral Crystal ◽  
Microwave Assisted ◽  
Time And Energy

Microwave-assisted crushing and grinding can improve efficiency and reduce energy consumption. This paper takes rock grains with galena and calcite as the research object to establish a two-dimensional computational model through the finite difference software FLAC2D. It analyzes the process and law of mineral boundary failure under microwave irradiation, and assesses the effects of four factors, namely, microwave irradiation time, power density, mineral crystal size, and mineral content, on mineral boundary failure. Results indicate an optimal microwave irradiation period for the rapid failure of mineral boundary. Moreover, irradiation time and energy consumption can be reduced by increasing the microwave power density. However, irradiation time and energy consumption are basically unchanged when the microwave power density is above a certain threshold. Mineral content slightly affects the microwave irradiation time, whereas mineral crystal size significantly affects the microwave irradiation time. In addition, a larger-sized mineral crystal requires less irradiation time and energy consumption to reach the same failure rate. However, irradiation time and energy consumption slightly change when the crystal size is larger than a certain value.

scholarly journals Time- and Temperature-Dependent Luminescence of Manganese Ions in Ceramic Magnesium Aluminum Spinels

Materials ◽  
2021 ◽  
Vol 14 (2) ◽  
pp. 420
Author(s):  
Nicholas Khaidukov ◽  
Angela Pirri ◽  
Maria Brekhovskikh ◽  
Guido Toci ◽  
Matteo Vannini ◽  
...  
Keyword(s):  
Solid State ◽  
Solid State Reaction ◽  
Broad Band ◽  
Solid State Reaction Method ◽  
Luminescence Spectroscopy ◽  
Luminescence Spectra ◽  
Manganese Ions ◽  
Time Resolved ◽  
Synthesis Conditions ◽  
Magnesium Aluminum Spinel

Samples of magnesium aluminum spinel ceramics doped with manganese ions were prepared by a high-temperature solid-state reaction method; their potential as red-emitting phosphors was analyzed using a time-resolved luminescence spectroscopy technique, from room temperature to 10 K. It was found that in the red spectral range, the luminescence spectra of manganese ions in the MgAl2O4 spinel showed a narrow band peaking at 651 nm due to the emission of Mn4+ and a broader emission band in the region of 675 ÷ 720 nm; the ratio of intensities for these bands depends on the synthesis conditions. By applying a special multi-step annealing procedure, the MgAl2O4:Mn4+ phosphor containing only tetravalent manganese ions, Mn4+, was synthesized. Broad-band far-red emission observed from MgAl2O4:Mn and Mg1.25Al1.75O3.75F0.25:Mn phosphors, prepared by a conventional method of a solid-state reaction, was interpreted as coming from Mn3+ ions.

Microwave-assisted solid-state sulphation of starch

e-Polymers ◽  
2007 ◽  
Vol 7 (1) ◽  
Author(s):  
Hanna Staroszczyk ◽  
Maciej Fiedorowicz ◽  
Wei Zhong ◽  
Piotr Janas ◽  
Piotr Tomasik
Keyword(s):  
Reaction Time ◽  
Solid State ◽  
Sulphuric Acid ◽  
Microwave Oven ◽  
Acid Anhydride ◽  
Reagent Ratio ◽  
Microwave Assisted ◽  
Higher Doses

AbstractStarch was sulphated with pyridine.SO3 complex in the microwaveassisted solid state processes in multimodal microwave oven and, for comparison, also on convectional heating blends of solid reagents. Starch was less hydrolysed in microwave-assisted reactions. The degree of the esterification of the sulphuric acid anhydride depended to a lesser extent on the reaction time and the power applied, and more essentially on the reagent ratio, that is, dose of the sulphating agent. Its higher doses favoured depolymerization and esterification leading to diesters, that is, crosslinking.

scholarly journals Microwave Assisted Alkaline Pretreatment of Algae Waste in the Production of Cellulosic Bioethanol

Energies ◽  
2021 ◽  
Vol 14 (18) ◽  
pp. 5891
Author(s):  
Rocío Maceiras ◽  
Víctor Alfonsín ◽  
Luis Seguí ◽  
Juan F. González
Keyword(s):  
Microwave Power ◽  
Reducing Sugars ◽  
Irradiation Time ◽  
Alkaline Pretreatment ◽  
Liquid Ratio ◽  
Fermentation Efficiency ◽  
Microwave Assisted ◽  
Microwave Effect ◽  
Solid Liquid ◽  
Bioethanol Yield

Biomass pretreatment has an important role in the production of cellulosic bioethanol. In this study, the effectiveness of microwave assisted alkaline pretreatment of algae waste was analysed. After pretreatment, the product was hydrolysed using sulphuric acid. The effects of microwave power, irradiating time, solid–liquid ratio and NaOH concentration were examined. Under the best conditions, the fermentable sugars were converted to cellulosic bioethanol using Saccharomyces Cerevisiae with a bioethanol yield of 1.93 ± 0.01 g/g and a fermentation efficiency of 40.4%. The reducing sugars concentration was 30% higher than that obtained from conventional hydrolysis without pretreatment. The obtained results suggest that microwave assisted alkaline pretreatment is effective in improving the production of cellulosic bioethanol of algae waste compared to that without microwave effect. Considering energy consumption, low microwave power and short microwave irradiation time are favourable for this pretreatment.

scholarly journals Screening of Microwave-Assisted-Batch Extraction Parameters for Recovering Total Phenolic and Flavonoid Contents from Chromolaena odorata Leaves through Two-Level Factorial Design

2019 ◽  
Vol 19 (2) ◽  
pp. 511 ◽  
Author(s):  
Oluwaseun Ruth Alara ◽  
Abdurahman Hamid Nour ◽  
Siti Kholijah Binti Abdul Mudalip
Keyword(s):  
Factorial Design ◽  
Microwave Power ◽  
Ethanol Concentration ◽  
Irradiation Time ◽  
Power Level ◽  
Feed Ratio ◽  
Total Phenolic ◽  
Chromolaena Odorata ◽  
Microwave Assisted ◽  
Microwave Power Level

Microwave-assisted extraction (MAE) of phenolic compounds from Chromolaena odorata leaves was investigated using one-factor-at-a-time (OFAT) and two-level factorial design. The MAE parameters studied were irradiation time (A: 1–5 min); microwave power level (B: 400-800 W); extraction temperature (C: 60–80 °C); solvent/feed ratio (D: 8:1–14:1 mL/g); and ethanol concentration (E: 20–60% v/v). The optima yields of TPC and TFC were 56.13 mg GAE/g d.w. and 44.78 mg QE/g d.w., respectively were achieved from MAE of C. odorata leaf at irradiation time of 2 min, microwave power of 600 W, temperature of 60 °C, solvent:feed ratio of 10:1 mL/g, and ethanol concentration of 40% v/v through one-factor-at-time (OFAT) experimental trials. The results obtained from a two-level factorial design experiments reflected that only ethanol concentration (20–60% v/v), irradiation time (1–5 min) and microwave power level (400–800 W) had significant effects on the yields of total phenolic content (TPC) and total flavonoid content (TFC) from C. odorata leaves (p < 0.05). However, temperature and solvent/feed ratio was not significant. In addition, the interactions AB (irradiation time and microwave power) and AE (irradiation time and ethanol concentration) contributed greatly to the recovery yields.

A rapid, microwave-assisted, one-pot cyclopropanation reaction to synthesize (4-ferrocenyl)benzoylcyclopropane in the solid state

2005 ◽  
Vol 83 (12) ◽  
pp. 2140-2143 ◽  
Author(s):  
Juxing Yin ◽  
Xiaolong Li ◽  
Xiaoli Wu ◽  
Baohua Chen ◽  
Zenglu Liu ◽  
...  
Keyword(s):  
Reaction Time ◽  
Solid State ◽  
Environmental Pollution ◽  
Intermediate Product ◽  
One Pot ◽  
Microwave Assisted ◽  
Sulfur Ylide

Some new (4-ferrocenyl)benzoylcyclopropanes were prepared rapidly via a microwave-assisted, one-pot cyclopropanation reaction in the solid state, directly using 4-ferrocenylacetophenone, aldehyde, and sulfur ylide as the starting materials. The main advantages of this procedure are convenient operation, shorter reaction time, lower environmental pollution, and no need to isolate the intermediate product (chalcone) in a separate step.Key words: 4-ferrocenylacetophenone, sulfur ylide, microwave-assisted, one-pot, solid state.

scholarly journals Phase Transformation of VO2Nanoparticles Assisted by Microwave Heating

2014 ◽  
Vol 2014 ◽  
pp. 1-8 ◽  
Author(s):  
Phatcharee Phoempoon ◽  
Lek. Sikong
Keyword(s):  
Microwave Power ◽  
Irradiation Time ◽  
Power Level ◽  
Thermal Analyses ◽  
Morphological Properties ◽  
Microwave Assisted Synthesis ◽  
Tem Analysis ◽  
Microwave Assisted ◽  
Thermochromic Properties ◽  
Microwave Power Level

The microwave assisted synthesis nowadays attracts a great deal of attention. Monoclinic phase VO2(M) was prepared from NH4VO3andH2C2O4·2H2Oby a rapid microwave assisted technique. The synthesis parameters, microwave irradiation time, microwave power, and calcinations temperature were systematically varied and their influences on the structure and morphology were evaluated. The microwave power level has been carried out in range 180–600 W. TEM analysis demonstrated nanosized samples. The structural and morphological properties were measured using XRD, TEM, and thermal analyses. The variations of vanadium phase led to thermochromic properties.

scholarly journals A Green Synthesis of a Novel Calix[4]Resorcinarene from 7-Hydroxycitronellal Using Microwave Irradiation

2018 ◽  
Vol 18 (1) ◽  
pp. 53
Author(s):  
Ratnaningsih Eko Sardjono ◽  
Iqbal Musthapa ◽  
Iis Rosliana ◽  
Fitri Khoerunnisa ◽  
Galuh Yuliani
Keyword(s):  
Energy Consumption ◽  
Reaction Time ◽  
Microwave Irradiation ◽  
Irradiation Time ◽  
Microwave Oven ◽  
Conventional Heating ◽  
Heating Method ◽  
Microwave Assisted ◽  
Domestic Microwave Oven ◽  
Waste Production

A new versatile macromolecule cyclic C-3,7-dimethyl-7-hydroxycalix[4]resorcinarene (CDHHK4R) has been synthesized from a fragrance agent, 7-hydroxycitronellal, via microwave irradiation. The reaction utilized a domestic microwave oven at various irradiation time and power to yield an optimum condition. As a comparison, the conventional heating method was also employed for the synthesis of the same calix[4]resorcinarene. Compared to the conventional method, microwave-assisted reaction effectively reduced the reaction time, the amount of energy consumption and the waste production. It is found that the synthesis of CDHHK4R by microwave irradiation yielded 77.55% of product, higher than by conventional heating which was only 62.17%.

Sign in / Sign up

Export Citation Format

Share Document