Ultrafine W-Cu Composite Powder Research Progress

2012 ◽  
Vol 535-537 ◽  
pp. 86-89 ◽  
Author(s):  
Jian Xin Gao ◽  
Yun Gang Li ◽  
Ying Tian ◽  
Yang Jiao
Keyword(s):  
Composite Powder ◽  
Sol Gel ◽  
Research Progress ◽  
Precipitation Method ◽  
Market Demand ◽  
Powder Preparation ◽  
Preparation Methods ◽  
Advantages And Disadvantages ◽  
Homogeneous Precipitation Method ◽  
Co Reduction

With the increased market demand of W-Cu composite materials, the research of ultrafine W-Cu composite powder is gradually in-depth, and some achievements have been made. This article describes some ultrafine W-Cu composite powder preparation methods in recent years, such as the mechanical alloying, oxide co-reduction, mechanical thermal chemical method, homogeneous precipitation method, spray drying, sol-gel method, etc. We simply analyzed the advantages and disadvantages of each method.

Recent Patents on Preparation Methods and Mechanical Stability of Superhydrophobic Surface

2021 ◽  
Vol 15 ◽  
Author(s):  
Zhaolong Li ◽  
Yingtao Liu
Keyword(s):  
Superhydrophobic Surface ◽  
Mechanical Stability ◽  
Sol Gel ◽  
Mechanical Action ◽  
Superhydrophobic Surfaces ◽  
Research Progress ◽  
Step Method ◽  
Preparation Methods ◽  
Advantages And Disadvantages ◽  
Application Fields

Background: Superhydrophobic surfaces have unique wettability and have shown broad application prospects in many fields, such as self-cleaning and lubrication drag reduction. However, the superhydrophobic surfaces are severely restricted by their poor mechanical stability in practical application, and the mechanical stability of the superhydrophobic surface is always affected by different preparation methods. Therefore, people pay more attention to the preparation methods of superhydrophobic surfaces. Objective: The study aims to improve the mechanical stability of the superhydrophobic surface and expand the application fields of the superhydrophobic surfaces; preparation methods of the superhydrophobic surface have been continuously improved. Methods: This paper reviews various representative patents and papers on preparation methods of the superhydrophobic surface at home and abroad. Results: In this review, the basic methods of preparing superhydrophobic surfaces were introduced, and three typical methods were summarized, such as etching method, coating method, and sol-gel method, then their advantages and disadvantages were discussed. In combination with the latest research progress, it is proposed that the use of environmentally friendly low surface energy modifiers and the use of the one-step method to prepare superhydrophobic surfaces are the future development trends. Aiming at the problem of the mechanical stability of superhydrophobic surfaces, the instability mechanism and stability evaluation methods of superhydrophobic surfaces under mechanical action are reviewed, and three basic methods to improve the mechanical stability of superhydrophobic surfaces are proposed. Conclusion: The optimization of the preparation method of the superhydrophobic surface is beneficial to improve the mechanical stability of the superhydrophobic surface and expand the application prospect of the superhydrophobic surfaces in various fields. More patents and papers on the superhydrophobic surface will be invented later.

Research Progress of Preparation Technology of Nano Copper Powder for 3D Printing

2018 ◽  
Vol 777 ◽  
pp. 150-157
Author(s):  
Jing Min Shi ◽  
Jian Wei Wang ◽  
Wei Xiao
Keyword(s):  
3D Printing ◽  
Copper Powder ◽  
Physical Vapor Deposition ◽  
Sol Gel ◽  
Radiation Chemistry ◽  
Research Progress ◽  
Chemical Methods ◽  
Advantages And Disadvantages ◽  
Explosion Method ◽  
Physical And Chemical

Nanocopper has become one of the research hotspots of metal powder for 3D printing, due to its excellent properties. In this paper, technical methods, process flow and research progress were systematically introduced of nanocopper powder for 3D printing. Preparation of nano-copper powder for 3D printing are mainly physical and chemical methods. Physical methods include atomization method, physical vapor deposition method, grinding method, electric explosion method. Chemical methods include sol-gel method, radiation chemistry, plasma, microemulsion, hydrothermal, liquid reduction and so on. The advantages and disadvantages of these methods were compared in detail, and the future development direction of nano-copper powder for 3D printing was look forward to.

The Preparation Approaches of Polymer/graphene Nanocomposites and their Appilcation Research Progress as Electrochemical Sensors

2017 ◽  
Vol 20 (4) ◽  
pp. 205-221 ◽  
Author(s):  
Weifeng Chen ◽  
Shaona Chen ◽  
Weimin Hu ◽  
Dejiang Li ◽  
Zhongxu Dai
Keyword(s):  
Electrochemical Sensors ◽  
Synergetic Effect ◽  
Research Progress ◽  
Honeycomb Lattice ◽  
Electrochemical Performances ◽  
Preparation Methods ◽  
Graphene Nanocomposites ◽  
Advantages And Disadvantages ◽  
Solution Blending

Graphene, a two-dimensional sheet of sp2-hybridized carbon atoms packed into a honeycomb lattice, can be combined with various polymers through different methods and techniques. Polymer/graphene nanocomposites are expected to not only preserve the fa-vorable properties of graphene and polymers, but also greatly enhance the intrinsic properties due to the synergetic effect between them. In this review, the preparation approaches of graphene/polymer nanocomposites, including melt blending, solution blending, in-situ polymeri-zation and in-situ synthesis, were presented comprehensively in order to study the relationship between these approaches and the final characteristics and performances. Each approach had different influences on the final properties of the nanocomposites. The advantages and disadvantages of the preparation methods were discussed respectively. Additionally, the application researches of the polymer/graphene nanocomposites as electrochemical sensors, were introduced in detail. With regard to some important or novel sensors, the mechanisms were proposed for reference. Finally, conclusions were given and the issues waiting to be settled for further development were pointed out. The current review demonstrates that polymer/graphene nanocomposites exhibit superior electrochemical performances and will be applied practically in the field of sensor devices.

Research Progress on Preparation of SiC/Al for Electronic Packaging by Liquid Infiltration

2021 ◽  
Vol 1035 ◽  
pp. 906-917
Author(s):  
Meng Qin Chen ◽  
Yue Long Bai ◽  
Zhi Feng Zhang
Keyword(s):  
Electronic Packaging ◽  
Volume Fraction ◽  
High Volume ◽  
Development Trend ◽  
Research Progress ◽  
Preparation Methods ◽  
Advantages And Disadvantages ◽  
Liquid Infiltration ◽  
Al Composite ◽  
The Development Trend

High volume fraction SiC/Al composite material, with its excellent thermal properties and flexible preparation process, has been widely used in the field of electronic packaging. In the paprer, the development of SiC/Al materials for electronic packaging and their preparation methods are reviewed. The preparation processes for preparing SiC/Al by liquid infiltration are mainly introduced. The advantages and disadvantages of several important processes are analyzed. Finally, the development trend of SiC/Al for electronic packaging prepared by liquid infiltration is prospected.

scholarly journals Effect of preparation methods on the activity of VOx/CeO2 catalysts for the selective catalytic reduction of NOx with NH3

2015 ◽  
Vol 5 (1) ◽  
pp. 389-396 ◽  
Author(s):  
Zhihua Lian ◽  
Fudong Liu ◽  
Hong He
Keyword(s):  
Selective Catalytic Reduction ◽  
Catalytic Reduction ◽  
Precipitation Method ◽  
Homogeneous Precipitation ◽  
Preparation Methods ◽  
Homogeneous Precipitation Method ◽  
Reduction Of Nox

VOx/CeO2 catalysts prepared by a homogeneous precipitation method exhibited high NOx conversion and strong SO2 resistance in NH3-SCR reaction.

Research Progress of the Counter Electrode in Dye-Sensitized Solar Cells

2010 ◽  
Vol 451 ◽  
pp. 63-78 ◽  
Author(s):  
Ying Tong Tang ◽  
Xu Pan ◽  
Song Yuan Dai ◽  
Chang Neng Zhang ◽  
Huan Jun Tian
Keyword(s):  
Counter Electrode ◽  
Dye Sensitized Solar Cells ◽  
Precious Metals ◽  
Research Progress ◽  
Counter Electrodes ◽  
Preparation Methods ◽  
Advantages And Disadvantages ◽  
Dye Sensitized ◽  
Different Types ◽  
Sensitized Solar Cells

This review covers recent research on counter electrodes using platinum (Pt), carbon and conducting polymers as catalysts for the reduction of triiodide in the dye-sensitized solar cell. Different types of counter electrode preparation methods and their advantages and disadvantages are compared. The inadequacy of the counter electrode with the precious metals and the advantages of the non-metallic-type counter electrode are pointed out. Especially, recent research on the Pt counter electrode in our group is discussed concerning with the reaction mechanism of the triiodide (I3-)/ iodide (I-) redox couple on the Pt counter electrode.

scholarly journals Technical Characteristics and Wear-Resistant Mechanism of Nano Coatings: A Review

Coatings ◽  
2020 ◽  
Vol 10 (3) ◽  
pp. 233 ◽  
Author(s):  
Yunqing Gu ◽  
Ke Xia ◽  
Denghao Wu ◽  
Jiegang Mou ◽  
Shuihua Zheng
Keyword(s):  
Wear Resistance ◽  
Vapor Deposition ◽  
Surface Effect ◽  
Research Progress ◽  
Material Surface ◽  
Preparation Methods ◽  
Wear Resistant ◽  
Advantages And Disadvantages ◽  
Nano Coating ◽  
Developed Surface

Nano-coating has been a hot issue in recent years. It has good volume effect and surface effect, and can effectively improve the mechanical properties, corrosion resistance and wear resistance of the coatings. It is important to improve the wear resistance of the material surface. The successful preparation of nano-coatings directly affects the application of nano-coatings. Firstly, the preparation methods of conventional surface coatings such as chemical vapor deposition and physical vapor deposition, as well as the newly developed surface coating preparation methods such as sol-gel method, laser cladding and thermal spraying are reviewed in detail. The preparation principle, advantages and disadvantages and the application of each preparation method in nano-coating are analyzed and summarized. Secondly, the types of nano-coating materials are summarized and analyzed by inorganic/inorganic nanomaterial coatings and organic/inorganic nanomaterial coatings, and their research progress is summarized. Finally, the wear-resistant mechanism of nano-coatings is revealed from three aspects: grain refinement, phase transformation toughening mechanism and nano-effects. The application prospects of nano-coatings and the development potential combined with 3D technology are prospected.

Luminescence Properties of Europium-Doped Yttrium Oxides Derived from Their Dodecylsulfate-Templated Mesostructure and Nanotube Forms

2003 ◽  
Vol 775 ◽  
Author(s):  
Tsuyoshi Kijima ◽  
Kenichi Iwanaga ◽  
Tomomi Hamasuna ◽  
Shinji Mohri ◽  
Mitsunori Yada ◽  
...  
Keyword(s):  
Room Temperature ◽  
Broad Band ◽  
Concentration Quenching ◽  
Precipitation Method ◽  
Homogeneous Precipitation ◽  
Bulk Materials ◽  
Main Band ◽  
Homogeneous Precipitation Method ◽  
Order Of Magnitude ◽  
Weak Luminescence

AbstractEuropium-doped hexagonal-mesostructured and nanotubular yttrium oxides templated by dodecylsulfate species as well as surfactant free bulk oxides were synthesized by the homogeneous precipitation method. All the as grown nanostructured or bulk materials with amorphous or poorly crystalline frameworks showed weak luminescence bands at room temperature. On calcination at 1000°C these materials were converted into highly crystalline yttrium oxides, resulting in a total increase in intensity of all the bands by one order of magnitude. In the hexagonal-mesostructured system, the main band due to the 5D0-7F2 transition for the calcined phases showed a sharp but asymmetrical multiplet splitting indicating multiple Eu sites. Concentration quenching was found at a Eu content of 3 mol% or above for these phases. In contrast, the main emission for the calcined solids in the nanotubular system occurred as poorly resolved broad band and the intensity of the main band at higher Eu content was significantly enhanced compared with those for the other two systems.

Recent Patents on Valve Mechanism Device

2020 ◽  
Vol 13 (3) ◽  
pp. 230-241
Author(s):  
Ye Dai ◽  
Hui-Bing Zhang ◽  
Yun-Shan Qi
Keyword(s):  
Nuclear Power ◽  
Power Plants ◽  
Nuclear Power Plants ◽  
Flow Direction ◽  
Research Progress ◽  
Valve Mechanism ◽  
Advantages And Disadvantages ◽  
Valve Structure ◽  
Valve Leakage ◽  
Safety And Reliability

Background: Valves are an important part of nuclear power plants and are the control equipment used in nuclear power plants. It can change the cross-section of the passage and the flow direction of the medium and has the functions of diversion, cutoff, overflow, and the like. Due to the earthquake, the valve leaks, which will cause a major nuclear accident, endangering people's lives and safety. Objective: The purpose of this study is to synthesize the existing valve devices, summarize and analyze the advantages and disadvantages of various devices from many literatures and patents, and solve some problems of existing valves. Methods: This article summarizes various patents of nuclear-grade valve devices and recent research progress. From the valve structure device, transmission device, a detection device, and finally to the valve test, the advantages and disadvantages of the valve are comprehensively analyzed. Results: By summarizing the characteristics of a large number of valve devices, and analyzing some problems existing in the valves, the outlook for the research and design of nuclear power valves was made, and the planning of the national nuclear power strategic goals and energy security were planned. Conclusion: Valve damage can cause serious safety accidents. The most common is valve leakage. Therefore, the safety and reliability of valves must be taken seriously. By improving the transmission of the valve, the problems of complicated valve structure and high cost are solved.

scholarly journals Yttrium Oxide Nanoparticle Synthesis: An Overview of Methods of Preparation and Biomedical Applications

2021 ◽  
Vol 11 (5) ◽  
pp. 2172
Author(s):  
Govindasamy Rajakumar ◽  
Lebao Mao ◽  
Ting Bao ◽  
Wei Wen ◽  
Shengfu Wang ◽  
...  
Keyword(s):  
Yttrium Oxide ◽  
Metal Oxide Nanoparticles ◽  
Sol Gel ◽  
Antioxidant Properties ◽  
Nanoparticle Synthesis ◽  
Synthetic Methods ◽  
Host Material ◽  
Solid State Reactions ◽  
Oxide Nanoparticles ◽  
Advantages And Disadvantages

Metal oxide nanoparticles demonstrate uniqueness in various technical applications due to their suitable physiochemical properties. In particular, yttrium oxide (Y2O3) nanoparticle is familiar for technical applications because of its higher dielectric constant and thermal stability. It is widely used as a host material for a variety of rare-earth dopants, biological imaging, and photodynamic therapies. Y2O3 has also been used as a polarizer, phosphor, laser host material, and in the optoelectronic fields for cancer therapy, biosensor, and bioimaging. Yttrium oxide nanoparticles have attractive antibacterial and antioxidant properties. This review focuses on the promising applications of Y2O3, its drawbacks, and its modifications. The synthetic methods of nanoparticles, such as sol-gel, emulsion, chemical methods, solid-state reactions, combustion, colloid reaction techniques, and hydrothermal processing, are recapitulated. Herein, we also discuss the advantages and disadvantages of Y2O3 NPs based biosensors that function through various detection modes including colorimetric, electrochemistry, and chemo luminescent regarding the detection of small organic chemicals, metal ions, and biomarkers.

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