Sintering and Hot-Pressing of Ti2AlC Obtained by SHS Process

2010 ◽  
Vol 63 ◽  
pp. 282-286 ◽  
Author(s):  
Leszek Chlubny ◽  
Jerzy Lis ◽  
Mirosław M. Bućko
Keyword(s):  
Hot Pressing ◽  
High Efficiency ◽  
Layer Structure ◽  
Low Cost ◽  
Max Phases ◽  
Fine Powders ◽  
High Temperature Synthesis ◽  
Low Energy Consumption ◽  
Potential Applications ◽  
Xrd Method

Some of ternary materials in the Ti-Al-C system are called MAX-phases and are characterised by heterodesmic layer structure. Their specific structure consisting of covalent and metallic chemical bonds influence its semi-ductile features locating them on the boundary between metals and ceramics, which may lead to many potential applications, for example as a part of a ceramic armour. Ti2AlC is one of this nanolaminate materials. Self-propagating High-temperature Synthesis (SHS) was applied to obtain sinterable powders of Ti2AlC Utilization of heat produced in exothermal reaction in adiabatic conditions to sustain process until all substrates are transformed into product is one of the advantages of the method that result in low energy consumption and low cost combined with high efficiency. Different substrates were used to produce fine powders of ternary material. Phase compositions of obtained powder were examined by XRD method. Than selected powders were used for sintering in various temperature both in a presureless sintering and hot-pressing in argon atmosphere. Properties and phase composition of obtained products were examined.

FEM-Based Analysis on the Process of Tube Stamping

2013 ◽  
Vol 690-693 ◽  
pp. 2315-2321
Author(s):  
Zhi Ming Wang ◽  
Shen Dong ◽  
Fu Li
Keyword(s):  
Finite Element Method ◽  
High Efficiency ◽  
Low Cost ◽  
Processing Method ◽  
Low Energy ◽  
Main Process ◽  
Feed Speed ◽  
Deformation Characteristics ◽  
Low Energy Consumption ◽  
Very High

Pipe stamping processing is a new kind of processing method ,which is high efficiency, low cost, low energy consumption .It has the very high practical value. Aiming at the tube punching force and deformation characteristics, the application of plastic finite element method was used to study the tube punching main process parameters on forming after the influence of wall collapse. Research shows that: wall collapse as tool feed speed increases first increases, then decreases to a certain degree; Along with the fixed die mandrel increases ; With the increase of the wall inside diameter increases.

Surface effects on optical and electrical properties of ZnO nanostructures

2010 ◽  
Vol 82 (11) ◽  
pp. 2055-2073 ◽  
Author(s):  
Cheng-Ying Chen ◽  
Ming-Wei Chen ◽  
Jr-Jian Ke ◽  
Chin-An Lin ◽  
José R. D. Retamal ◽  
...  
Keyword(s):  
High Efficiency ◽  
Surface Effect ◽  
Low Cost ◽  
Dye Sensitized Solar Cells ◽  
Surface Effects ◽  
Industrial Applications ◽  
Zno Nanostructures ◽  
New Class ◽  
Potential Applications ◽  
Sensitized Solar Cells

This article presents a comprehensive review of the current research addressing the surface effects on physical properties and potential applications of nanostructured ZnO. Studies illustrating the transport, photoluminescence (PL), and photoconductivity properties of ZnO with ultrahigh surface-to-volume (S/V) ratio are reviewed first. Secondly, we examine recent studies of the applications of nanostructured ZnO employing the surface effect on gas/chemical sensing, relying on a change of conductivity via electron trapping and detrapping process at the surfaces of nanostructures. Finally, we comprehensively review the photovoltaic (PV) application of ZnO nanostructures. The ultrahigh S/V ratios of nanostructured devices suggest that studies on the synthesis and PV properties of various nanostructured ZnO for dye-sensitized solar cells (DSSCs) offer great potential for high efficiency and low-cost solar cell solutions. After surveying the current literature on the surface effects on nano-structured ZnO, we conclude this review with personal perspectives on a few surface-related issues that remain to be addressed before nanostructured ZnO devices can reach their ultimate potential as a new class of industrial applications.

Study of Film Layer Structure and Resistance on High Strength Room Temperature Blackening

2014 ◽  
Vol 687-691 ◽  
pp. 4183-4186
Author(s):  
Yu Feng Zhang ◽  
Xi Zhang ◽  
Min Rui Li ◽  
Bo Wang
Keyword(s):  
Wear Resistance ◽  
Room Temperature ◽  
High Efficiency ◽  
Treatment Time ◽  
Layer Structure ◽  
Low Cost ◽  
High Strength ◽  
P System ◽  
Short Treatment ◽  
Film Layer

In this paper, the high strength room temperature blackening film on steel surface were prepared, the structure and the forming principle of the film were studied. The procedure of the Cu-Se-P system high strength composition blackening was researched, and the factors that affect the wear resistance of the film were analyzed [1]. The experiment shows that the procedure have many virtues, such as short treatment time, high efficiency, low cost, high adhesive strength, perfect wear resistance, which posed a new approach for blackening of machine parts.

scholarly journals Low-Cost Air Gap Metasurface Structure for High Absorption Efficiency Energy Harvesting

2019 ◽  
Vol 2019 ◽  
pp. 1-8 ◽  
Author(s):  
Wei Hu ◽  
Zhao Yang ◽  
Fading Zhao ◽  
Guangjun Wen ◽  
Jian Li ◽  
...  
Keyword(s):  
High Efficiency ◽  
Layer Structure ◽  
Low Cost ◽  
Single Layer ◽  
Absorption Efficiency ◽  
Air Gap ◽  
Wireless Power ◽  
Low Loss ◽  
Dielectric Substrates ◽  
High Absorption

This manuscript deals with the design of a metamaterial-based surface structure for high efficiency wireless power harvesting or collection. Differently from the previously presented structures which require the use of thicker and low-loss (and for this reason high cost) dielectric substrates, the presented work employs a dual-layer structure with a thin low-loss material and an air gap; they allow for the design of very high absorption efficiency metamaterial-based surfaces, with noticeably reduced costs. Furthermore, the air gap thickness can be used as a new degree-of-freedom (more easily adjustable than the thickness of a single-layer structure) for the optimization of other design requirements such as bandwidth or structure sizes. In comparison with other existing designs, the proposed metasurface shows a comparable absorption efficiency of 84.4% but with a larger power collection surface and lower costs.

scholarly journals Manganese-Based Catalysts for Indoor Volatile Organic Compounds Degradation with Low Energy Consumption and High Efficiency

2021 ◽  
Author(s):  
Yanbo Li ◽  
Shuhe Han ◽  
Liping Zhang ◽  
Yifu Yu
Keyword(s):  
Energy Consumption ◽  
Volatile Organic Compounds ◽  
Organic Compounds ◽  
High Efficiency ◽  
Low Cost ◽  
Catalytic Degradation ◽  
Low Energy ◽  
Metal Catalyst ◽  
Low Energy Consumption ◽  
Volatile Organic

AbstractWith the development of industrialization, the emission of volatile organic compounds (VOCs) to atmosphere causes serious environmental problems and the treatment of VOCs needs to consume a lot of energy. Moreover, indoor VOCs are seriously harmful to human health. Thus, there is an urgent requirement for the development of indoor VOCs treatment technologies. Catalytic degradation of VOCs, as a low energy consumption, high efficiency, and easy to achieve manner, has been widely studied in related fields. As a kind of transition metal catalyst, manganese-based catalysts have attracted a lot of attention in the catalytic degradation of VOCs because of their unique advantages including high efficiency, low cost, and excellent stability. This paper reviews the state-of-the-art progress of manganese-based catalysts for VOCs catalytic degradation. We introduce the thermocatalytic, photocatalytic and photo-thermocatalytic degradation of VOCs on manganese-based catalysts in this paper. The optimization of manganese-based catalysts by means of structural design, decorating modification and defect engineering is discussed. Graphical Abstract

Preparation of High-quality Graphene via Electrochemical Exfoliation in Acidic Electrolytes: A Review

MRS Advances ◽  
2017 ◽  
Vol 2 (30) ◽  
pp. 1611-1619 ◽  
Author(s):  
Youning Gong ◽  
Chunxu Pan
Keyword(s):  
Technological Innovation ◽  
Material Science ◽  
Recent Progress ◽  
High Efficiency ◽  
Low Cost ◽  
High Quality ◽  
Chemical Methods ◽  
Electrochemical Exfoliation ◽  
Potential Applications ◽  
Wet Chemical

ABSTRACTSince the discovery of graphene in 2004, graphene has already been one of the researching hotspots in the material science. As a promising method, electrochemical exfoliation has drawn great attention for producing graphene on industrial scale with high efficiency, low cost, and non-pollution. However, like other wet-chemical methods, the induced oxidation and chemical functionalization are unavoidable during the exfoliation process. Several solutions have been reported to overcome this issue and improve the graphene quality. In this review, we summarize the recent progress in preparation and potential applications of high-quality graphene via electrochemical exfoliation in acidic electrolytes, focusing on the technological innovation and related properties of obtained high-quality graphene.

Synthesis, Optical Properties and Applications of Ternary Oxide Nanoparticles by a Microwave Technique

2021 ◽  
Vol 21 (10) ◽  
pp. 5307-5311
Author(s):  
Mingling Liu ◽  
Meiling Sun ◽  
Zhijia Wang
Keyword(s):  
Optical Properties ◽  
High Efficiency ◽  
Low Cost ◽  
Ternary Oxide ◽  
Structural And Optical Properties ◽  
High Demand ◽  
Microwave Technique ◽  
Binary Oxides ◽  
Nanomaterial Synthesis ◽  
Potential Applications

Nanocrystal preparation is in high demand due to the development of nanodevices. Nanostructures or microstructures of binary oxides such as TiO2, ZnO, and Al2O3 have been extensively prepared and studied. Synthesis of ternary oxide nanomaterials with controlled structures, morphologies, and sizes are of interest due to their potential applications in nanodevices caused by tunable energy level, bandgap, and structure. In this work, a solution-based method is used to prepare CaWO4 and LaPO4 ternary oxide nanomaterials by microwave technique. Controlled sizes and morphologies including nanorods and microspheres are synthesized by the microwave method, which is believed to be a facile and low-cost technique for the synthesis of ternary oxide nanomaterials. Furthermore, the (relatively) quick process enables high efficiency of the production. The structural and optical properties of the prepared nanomaterials are also investigated in this work. This work benefits nanomaterial synthesis for nanomanufacturing and applications in lighting and photodynamic activations as well as optical storage.

The Development and Applications of the Dust and Rhenium Recovery Integrated Device of Calcination Exhaust of Molybdenum Concentrate which Contain Rhenium

2013 ◽  
Vol 753-755 ◽  
pp. 40-43 ◽  
Author(s):  
Guo Wei Xie ◽  
Ming Ming Li ◽  
Yi Wei Yang
Keyword(s):  
Simple Structure ◽  
High Efficiency ◽  
Low Cost ◽  
The Self ◽  
Dust Collector ◽  
Production Practice ◽  
Low Energy Consumption ◽  
Dust Catcher ◽  
Molybdenum Concentrate ◽  
Integrated Device

A device, was used to recover dust and rhenium from molybdenum concentrate roasting exhaust gas, was developed. The device combine the self-swash dust catcher and spherical tray tower technology: the self-swash dust catcher was used to recover dust and rhenium; spherical tray tower was used to further dust and rhenium recovery and its application to engineering in practice. This was the first successful such devices used to recover dust and rhenium integration from calcination exhaust of molybdenum concentrate which contain rhenium in production practice. Through production practice, proved that the device is feasible, with high efficiency. And it has the advantages of simple structure, convenient operation, low cost and low energy consumption etc.. In addition, the dust removing system can also be used to the wet dust collector in the filed of metallurgical , mining, chemical and building.

Influence of MBE Growth Conditions on Dislocation Densities of GaAs/Ge Epilayers Grown on Silicon Substrates

1985 ◽  
Vol 43 ◽  
pp. 364-365
Author(s):  
K.M. Hones ◽  
P. Sheldon ◽  
B.G. Yacobi ◽  
A. Mason
Keyword(s):  
High Efficiency ◽  
Lattice Mismatch ◽  
Low Cost ◽  
Growth Conditions ◽  
Nonradiative Recombination ◽  
Device Structure ◽  
Si Substrates ◽  
Transmission Electron ◽  
Dislocation Densities ◽  
Dislocation Type

There is increasing interest in growing epitaxial GaAs on Si substrates. Such a device structure would allow low-cost substrates to be used for high-efficiency cascade- junction solar cells. However, high-defect densities may result from the large lattice mismatch (∼4%) between the GaAs epilayer and the silicon substrate. These defects can act as nonradiative recombination centers that can degrade the optical and electrical properties of the epitaxially grown GaAs. For this reason, it is important to optimize epilayer growth conditions in order to minimize resulting dislocation densities. The purpose of this paper is to provide an indication of the quality of the epitaxially grown GaAs layers by using transmission electron microscopy (TEM) to examine dislocation type and density as a function of various growth conditions. In this study an intermediate Ge layer was used to avoid nucleation difficulties observed for GaAs growth directly on Si substrates. GaAs/Ge epilayers were grown by molecular beam epitaxy (MBE) on Si substrates in a manner similar to that described previously.

Improvement of Ti/RuO2–IrO2 Anode Lifetime and Electrocatalytical Properties by Using an Eco-Friendly Thermal Decomposition Method Using Polyvinyl Alcohol as Solvent

2019 ◽  
Author(s):  
Charlys Bezerra ◽  
Géssica Santos ◽  
Marilia Pupo ◽  
Maria Gomes ◽  
Ronaldo Silva ◽  
...  
Keyword(s):  
Thermal Decomposition ◽  
Polyvinyl Alcohol ◽  
High Efficiency ◽  
Electrochemical Impedance ◽  
Pechini Method ◽  
Low Cost ◽  
Charge Transfer Resistance ◽  
Transfer Resistance ◽  
Calcination Temperatures ◽  
Service Lifetime

<p>Electrochemical oxidation processes are promising solutions for wastewater treatment due to their high efficiency, easy control and versatility. Mixed metal oxides (MMO) anodes are particularly attractive due to their low cost and specific catalytic properties. Here, we propose an innovative thermal decomposition methodology using <a>polyvinyl alcohol (PVA)</a> as a solvent to prepare Ti/RuO<sub>2</sub>–IrO<sub>2</sub> anodes. Comparative anodes were prepared by conventional method employing a polymeric precursor solvent (Pechini method). The calcination temperatures studied were 300, 400 and 500 °C. The physical characterisation of all materials was performed by X-ray diffraction and scanning electron microscopy coupled with energy dispersive spectroscopy, while electrochemical characterisation was done by cyclic voltammetry, accelerated service lifetime and electrochemical impedance spectroscopy. Both RuO<sub>2</sub> and IrO<sub>2</sub> have rutile-type structures for all anodes. Rougher and more compact surfaces are formed for the anodes prepared using PVA. Amongst temperatures studied, 300 °C using PVA as solvent is the most suitable one to produce anodes with expressive increase in voltammetric charge (250%) and accelerated service lifetime (4.3 times longer) besides reducing charge-transfer resistance (8 times lower). Moreover, the electrocatalytic activity of the anodes synthesised with PVA toward the Reactive Blue 21 dye removal in chloride medium (100 % in 30 min) is higher than that prepared by Pechini method (60 min). Additionally, the removal total organic carbon point out improved mineralisation potential of PVA anodes. Finally, this study reports a novel methodology using PVA as solvent to synthesise Ti/RuO<sub>2</sub>–IrO<sub>2</sub> anodes with improved properties that can be further extended to synthesise other MMO compositions.</p>

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