scholarly journals Decomposition Study of Praseodymium Oxalate as a Precursor for Praseodymium Oxide in the Microwave Field

ACS Omega ◽  
2020 ◽  
Vol 5 (34) ◽  
pp. 21338-21344
Author(s):  
Peng Lv ◽  
Liangjing Zhang ◽  
Sivasankar Koppala ◽  
Kaihua Chen ◽  
Yuan He ◽  
...  
Keyword(s):  
Microwave Field ◽  
Praseodymium Oxide

Interference Effects of a Powerful Pulsed Microwave Field on Microphone Devices

2007 ◽  
Vol 66 (17) ◽  
pp. 1583-1590
Author(s):  
A. V. Berdyshev ◽  
V. V. Shcherenkov ◽  
A. P. Yarygin ◽  
Vladimir B. Avdeev
Keyword(s):  
Microwave Field ◽  
Interference Effects

THE ENERGY EFFICIENCY TECHNIQUE OF THERMAL PROCESSING OF GRAIN

2019 ◽  
pp. 176-182
Author(s):  
А. Zykov ◽  
S. Orlova ◽  
L. Ovsiannykova
Keyword(s):  
Energy Efficiency ◽  
Thermal Processing ◽  
Microwave Field ◽  
Low Frequency ◽  
Heat Pipes ◽  
Biologically Active ◽  
Microwave Drying ◽  
Post Harvest ◽  
Combined Action ◽  
Frequency Radiation

The methods of energy efficiency increasing of pre- and post-harvest thermal processing of grain are considered. The effective ways to deliver energy to the grain using heat pipes and microwave field are given. The effect of combined action of microwave and low-frequency radiation on the grain germination is shown. Currently, the intensification of technological processes under the influence of microwave radiation is used in many industrial processes. Microwave equipment is becoming a necessary technological component of large profitable industries. The process of drying is no exception. In recent years, new versions of dryers have been proposed that use combined methods of energy supply, including microwave energy. Microwave dryers for foodstuffs, grains and oilseeds, including those for seed stock, have been created and are beginning to be used, along with drying and disinfection, disinfection of drying products from harmful bacteria, fungi, and mildew. For the implementation of microwave drying of particular importance is the choice of regime parameters of drying, given the fact that the grain is a biologically active object. Microwave drying allows you to provide a powerful flow of energy to the object of drying and to obtain a significant intensification of moisture evaporation. But at the same time there is also an intense heating of the product, which can degrade its quality. The possibility of supplying energy throughout the cross section of the product allows for the evaporation of moisture from the inner layers of the product, which is especially important at the end of drying, when the zone of evaporation of moisture is significantly deeper. Therefore, the highest drying efficiency can be obtained in combined processes that take advantage of various drying methods, such as convective, as well as the use of microwave and low-frequency magnetic fields. The paper presents effective ways to supply energy to the grain using heat pipes and a microwave field. The effect of the combined action of microwave and low-frequency radiation on grain similarity is shown. Ways to improve the energy efficiency of the processes of preseeding and post-harvest heat treatment of grain are considered.

Oxidation decomposition of toluene waste gas by catalyst in microwave field

2018 ◽  
Vol 35 (6) ◽  
pp. 582 ◽  
Author(s):  
Ning WANG ◽  
Bin GUO ◽  
Xin WANG ◽  
Xurui HU ◽  
Ailing REN ◽  
...  
Keyword(s):  
Microwave Field ◽  
Waste Gas

Mathematical Description of the Influence of the Bunker Outlet on the Grain Motion in the Microwave Convective Area

2020 ◽  
pp. 73-80
Author(s):  
Aleksey N. Vasil’yev ◽  
Andrey A. Tsymbal ◽  
Aleksey A. Vasil’yev
Keyword(s):  
Mathematical Description ◽  
Microwave Field ◽  
Convective Zone ◽  
Research Purpose ◽  
Field Zone ◽  
Flow Process ◽  
Grain Processing ◽  
Grain Flow ◽  
The Right ◽  
Processing Zone

One of the environmentaly friendly methods of drying and decontamination of grain is its processing in microwave-convective installations. The efficiency of using the microwave field depends on the uniformity of its distribution in the grain processing zone. This is provided by the design features of the microwave core and waveguides. The uniformity of grain movement in the microwave field zone is important. It is important that the grain is moved in the microwave convective zone by hydraulic movement. In this case, the grain passes through zones with different intensity of the microwave field sequentially and the grain processing is uniform. (Research purpose) The research purpose is in making a mathematical dependence of parameters of the hopper outlet on the movement of grain in the microwave convective zone. (Materials and methods) The article presents the parameters of the outlet that ensure the grain flow without forming static arches in accordance with the method of calculating outlet bins. Fluctuations in humidity for different crops of processed grain will not lead to a violation of the grain flow process. The resulting equation for changing the height of the dynamic arch, depending on its location in the height of the hopper, allows to determine the uneven flow of grain from the hopper outlet. (Results and discussion) When unloading grain, there is an uneven flow in the right and left halves of the hopper, relative to the central axis. When only one hopper is unloaded, 0.84 kilograms more wheat is unloaded from its left half than from the right. This difference leads to uneven and reduced efficiency of grain processing in the microwave-convective zone. (Conclusions) To ensure the uniformity of grain processing in the microwave convective zone, it is necessary to improve the mechanism of grain flow from the outlet of the hopper.

Microwave Field Distribution Uniformity Coefficient in the Grain Mass

2020 ◽  
Vol 67 (2) ◽  
pp. 87-92
Author(s):  
Dmitriy A. Budnikov
Keyword(s):  
Electromagnetic Field ◽  
Numerical Experiment ◽  
Microwave Field ◽  
Research Purpose ◽  
Coefficient Of Determination ◽  
Material Research ◽  
Dense Layer ◽  
Uniformity Coefficient ◽  
Average Value ◽  
Processed Material

The article considers the microwave electromagnetic fields as one of the options for improving the thermal drying of grain. Their application is limited by the high unevenness of the field propagation in the layer of the processed material. (Research purpose) The research purpose is in justifying the uniformity of distribution of microwave field in the layer of the processed grain. (Materials and methods) The article presents the scheme of computer models of microwave processing zones and waveguides, properties of materials for conducting a numerical experiment. (Results and discussion) A numerical experiment was performed to determine the uniformity coefficient of propagation of the microwave field in a layer of grain material. The article presents the dependencies. (Conclusions) It was found that the results of modeling the distribution of the electromagnetic field in the zone of microwave convective influence of the installation containing two sources of microwave power for processing the grain layer indicate a high level of its unevenness in the volume of the product pipeline. To assess the uniformity of the distribution of the electromagnetic field in the working area of a laboratory installation, there used a coefficient that is the ratio of the average value of the intensity in the zone of microwave convective action to its average value of the wave strength passing through the output of the waveguide. The values of the uniformity coefficient in the considered implementation options are in the range of 0.1757-0.4946 for a dense layer of wheat. To ensure a sufficient level of uniformity of the electromagnetic wave distribution in the volume of the microwave convective zone, the uniformity coefficient must be higher than 0.37. The article presents the dependence of the uniformity coefficient of the electromagnetic field on the humidity of the processed material by a third-degree polynomial with a coefficient of determination higher than 0.98.

Dual-gate gallium-arsenide microwave field-effect transistor

1971 ◽  
Vol 7 (22) ◽  
pp. 661 ◽  
Author(s):  
J.A. Turner ◽  
A.J. Waller ◽  
E. Kelly ◽  
D. Parker
Keyword(s):  
Gallium Arsenide ◽  
Field Effect ◽  
Field Effect Transistor ◽  
Microwave Field ◽  
Dual Gate ◽  
Effect Transistor

scholarly journals Dielectric properties and thermal behavior of electrolytic manganese anode mud in microwave field

2020 ◽  
Vol 384 ◽  
pp. 121227 ◽  
Author(s):  
Kangqiang Li ◽  
Jin Chen ◽  
Jinhui Peng ◽  
Roger Ruan ◽  
Mamdouh Omran ◽  
...  
Keyword(s):  
Dielectric Properties ◽  
Thermal Behavior ◽  
Microwave Field ◽  
Electrolytic Manganese

scholarly journals Promotional Effects of Rare-Earth Praseodymium (Pr) Modification over MCM-41 for Methyl Mercaptan Catalytic Decomposition

Processes ◽  
2021 ◽  
Vol 9 (2) ◽  
pp. 400
Author(s):  
Xiaohua Cao ◽  
Jichang Lu ◽  
Yutong Zhao ◽  
Rui Tian ◽  
Wenjun Zhang ◽  
...  
Keyword(s):  
Dimethyl Sulfide ◽  
Catalytic Decomposition ◽  
Product Distribution ◽  
Acid Sites ◽  
Methyl Mercaptan ◽  
Praseodymium Oxide ◽  
X Ray ◽  
Xps Characterization ◽  
Temperature Programmed ◽  
Mcm 41

Praseodymium (Pr)-promoted MCM-41 catalyst was investigated for the catalytic decomposition of methyl mercaptan (CH3SH). Various characterization techniques, such as X-ray diffraction (XRD), N2 adsorption–desorption, temperature-programmed desorption of ammonia (NH3-TPD) and carbon dioxide (CO2-TPD), hydrogen temperature-programmed reduction (H2-TPR), and X-ray photoelectron spectrometer (XPS), were carried out to analyze the physicochemical properties of material. XPS characterization results showed that praseodymium was presented on the modified catalyst in the form of praseodymium oxide species, which can react with coke deposit to prolong the catalytic stability until 120 h. Meanwhile, the strong acid sites were proved to be the main active center over the 10% Pr/MCM-41 catalyst by NH3-TPD results during the catalytic elimination of methyl mercaptan. The possible reaction mechanism was proposed by analyzing the product distribution results. The final products were mainly small-molecule products, such as methane (CH4) and hydrogen sulfide (H2S). Dimethyl sulfide (CH3SCH3) was a reaction intermediate during the reaction. Therefore, this work contributes to the understanding of the reaction process of catalytic decomposition methyl mercaptan and the design of anti-carbon deposition catalysts.

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