scholarly journals Получение керамики на основе карбида кремния из золошлаковых отходов

2020 ◽  
Vol 46 (14) ◽  
pp. 21
Author(s):  
А.Я. Пак ◽  
В.Е. Губин ◽  
Г.Я. Мамонтов
Keyword(s):  
Silicon Carbide ◽  
Direct Current ◽  
Final Stage ◽  
Analytical Methods ◽  
Arc Discharge ◽  
Ambient Air ◽  
Powder Product ◽  
Three Stages ◽  
Sintering Method ◽  
Carbon Plasma

The paper shows the possibility of obtaining bulk samples of solid ceramics based on silicon carbide obtained from ash waste. The process is implemented in three stages: the initial ash waste was treated with a carbon plasma of a direct current arc discharge under ambient air conditions using a vacuumless method, then the obtained powder material was purified from unbounded carbon in an atmospheric furnace, and at the final stage the powder product was sintered by the plasma spark sintering method. According to analytical methods, the result is a ceramic based on silicon carbide with a density of 3.05 g/cm3 and a hardness of up to 19.9 GPa.

Effect of energy on the phase composition of the product of arc discharge synthesis in the tungsten-carbon system obtained in a self-shielding autonomous gas environment

2020 ◽  
Vol 10 ◽  
pp. 79-87
Author(s):  
A. Ya. Pak ◽  
◽  
A. I. Kokorina ◽  
Keyword(s):  
Electron Microscopy ◽  
Phase Composition ◽  
Direct Current ◽  
Arc Discharge ◽  
Atmospheric Oxygen ◽  
Ambient Air ◽  
Synthesis Product ◽  
Powder Materials ◽  
Tungsten Carbides ◽  
Carbon System

The paper presents the results of experimental studies on the preparation of ultrafine powder materials of the tungsten-carbon system in the plasma of a direct current arc discharge initiated in an ambient air. According to the results of X-ray diffractometry, transmission electron microscopy, scanning electron microscopy, and elemental analysis, the product identifies micro-sized and nanoscale crystalline objects that are carbon graphite-like materials gC, tungsten carbides WC and W2C with a hexagonal structure, tungsten W with a cubic structure. As a result of a series of experiments, the possibility of influencing the phase composition of the synthesis product by the amount of energy supplied, which is linearly dependent on the duration of the arc discharge, was established. In this case, tungsten oxide phases were not found in the composition of the synthesis products within the framework of the applied analytical techniques. The process of obtaining non-oxide materials during the generation of a direct current arc plasma in the presence of carbon and tungsten is possible due to the intense generation of carbon monoxide and carbon dioxide gases, which shield the reaction volume from atmospheric oxygen. Thus, in the framework of the presented work, the possibility of controlling the phase composition of the product of vacuumless arc synthesis in the tungsten-carbon system by changing the duration of the discharge burning at a constant direct current was shown for the first time.

A novel approach of waste tires rubber utilization via ambient air direct current arc discharge plasma

2022 ◽  
Vol 227 ◽  
pp. 107111
Author(s):  
A.Ya. Pak ◽  
K.B. Larionov ◽  
E.N. Kolobova ◽  
K.V. Slyusarskiy ◽  
J. Bolatova ◽  
...  
Keyword(s):  
Direct Current ◽  
Discharge Plasma ◽  
Arc Discharge ◽  
Ambient Air ◽  
Waste Tires ◽  
Novel Approach

scholarly journals Безвакуумный метод получения кубического карбида титана в плазме низковольтного дугового разряда постоянного тока

2019 ◽  
Vol 45 (1) ◽  
pp. 5
Author(s):  
А.Я. Пак
Keyword(s):  
Titanium Carbide ◽  
Direct Current ◽  
Diffraction Data ◽  
Discharge Plasma ◽  
Arc Discharge ◽  
X Ray Diffraction ◽  
X Ray ◽  
Powder Product

AbstractThe results of a study on the production of cubic titanium carbide in direct-current arc discharge plasma initiated in open air are presented. A feature of the method is its implementation without the use of gas or liquid protective media preventing the oxidation of products and initial reagents with air oxygen. According to the X-ray diffraction data, graphite gC, hexagonal titanium α-Ti, and cubic titanium carbide TiC are identified in the composition of the powder product. The TiC particles are represented by objects with a regular characteristic cut and sizes from units to tens of micrometers.

The Subject Matter of Intellectual Property

2017 ◽  
Author(s):  
Justine Pila
Keyword(s):  
Intellectual Property ◽  
Subject Matter ◽  
Final Stage ◽  
Theoretical Framework ◽  
Trade Mark ◽  
Second Stage ◽  
Essential Properties ◽  
The Subject ◽  
Three Stages ◽  
The Relationship

This book offers a study of the subject matter protected by each of the main intellectual property (IP) regimes. With a focus on European and UK law particularly, it considers the meaning of the terms used to denote the objects to which IP rights attach, such as ‘invention’, ‘authorial work’, ‘trade mark’, and ‘design’, with reference to the practice of legal officials and the nature of those objects specifically. To that end it proceeds in three stages. At the first stage, in Chapter 2, the nature, aims, and values of IP rights and systems are considered. As historically and currently conceived, IP rights are limited (and generally transferable) exclusionary rights that attach to certain intellectual creations, broadly conceived, and that serve a range of instrumentalist and deontological ends. At the second stage, in Chapter 3, a theoretical framework for thinking about IP subject matter is proposed with the assistance of certain devices from philosophy. That framework supports a paradigmatic conception of the objects protected by IP rights as artifact types distinguished by their properties and categorized accordingly. From this framework, four questions are derived concerning: the nature of the (categories of) subject matter denoted by the terms ‘invention’, ‘authorial work’, ‘trade mark’, ‘design’ etc, including their essential properties; the means by which each subject matter is individuated within the relevant IP regime; the relationship between each subject matter and its concrete instances; and the manner in which the existence of a subject matter and its concrete instances is known. That leaves the book’s final stage, in Chapters 3 to 7. Here legal officials’ use of the terms above, and understanding of the objects that they denote, are studied, and the results presented as answers to the four questions identified previously.

scholarly journals Synthesis of silicon carbide in arc discharge in fuel oil

2021 ◽  
Vol 1870 (1) ◽  
pp. 012005
Author(s):  
B A Timerkaev ◽  
V S Felzinger ◽  
A Akhmetvaleeva ◽  
D A Zainutdinova ◽  
A A Zalyalieva ◽  
...  
Keyword(s):  
Silicon Carbide ◽  
Arc Discharge ◽  
Fuel Oil

Effects of Two-Step DC Electrochemical Pretreatment of Fine Grinding WC-Co Tool Surface on Morphology and Quality of Diamond Coatings

2011 ◽  
Vol 337 ◽  
pp. 59-62
Author(s):  
Xiang Hui Zhang ◽  
Ling Wang ◽  
Jian Ping Long
Keyword(s):  
Surface Morphology ◽  
Direct Current ◽  
Arc Discharge ◽  
Etching Time ◽  
Diamond Coating ◽  
Diamond Coatings ◽  
Fine Grinding ◽  
Electrolytic Etching ◽  
Electrochemical Pretreatment

In the present investigation, diamond coating was deposited on fine grinding cemented carbide substrate by direct current arc discharge chemical vapor deposition. The effect of electrolytic etching time in the two-step electrochemical pretreatment process (firstly using electrolytic etching, and then using acid etching) on morphology and quality of the diamond coating were systemically studied. The surface morphology feature and quality of diamond coatings were characterized by means of Scanning Electron Microscope (SEM), laser Raman spectrometer respectively. The results showed that the electrolytic etching duration has distinctly effect on the quality and crystal features such as morphology, crystal type and grain size of diamond coating. It showed that as electrolytic current is direct current 3A, electrolytic etching time altering from 0.5 min to 7.5min, the surface morphology of diamond films gradually transition from microcrystalline cubic-octahedron to cauliflower type nanocluster, and further increase the electrolytic etching time, will lead to several negative effects on the quality and nucleation of the coatings which is not only retard the diamond nucleation, but also promote the formation of graphite.

Three Stages Modeling of n-Octane Reforming Assisted by a Nonthermal Arc Discharge

2009 ◽  
Vol 23 (10) ◽  
pp. 4931-4936 ◽  
Author(s):  
José Gonzalez-Aguilar ◽  
Guillaume Petitpas ◽  
Alexandre Lebouvier ◽  
Jean-Damien Rollier ◽  
Adeline Darmon ◽  
...  
Keyword(s):  
Arc Discharge ◽  
Three Stages

Controllable synthesis of carbon nanomaterials by direct current arc discharge from the inner wall of the chamber

Carbon ◽  
2019 ◽  
Vol 142 ◽  
pp. 278-284 ◽  
Author(s):  
Da Zhang ◽  
Kai Ye ◽  
Yaochun Yao ◽  
Feng Liang ◽  
Tao Qu ◽  
...  
Keyword(s):  
Direct Current ◽  
Carbon Nanomaterials ◽  
Arc Discharge ◽  
Controllable Synthesis

scholarly journals Preparation of Nickel Nanoparticles by Direct Current Arc Discharge Method and Their Catalytic Application in Hybrid Na-Air Battery

Nanomaterials ◽  
2018 ◽  
Vol 8 (9) ◽  
pp. 684 ◽  
Author(s):  
Fengmei Su ◽  
Xuechao Qiu ◽  
Feng Liang ◽  
Manabu Tanaka ◽  
Tao Qu ◽  
...  
Keyword(s):  
Direct Current ◽  
Composite Structures ◽  
High Speed ◽  
Large Scale ◽  
Nickel Nanoparticles ◽  
Arc Discharge ◽  
Band Pass Filter ◽  
Pass Filter ◽  
Air Battery ◽  
Discharge Method

Nickel nanoparticles were prepared by the arc discharge method. Argon and argon/hydrogen mixtures were used as plasma gas; the evaporation of anode material chiefly resulted in the formation of different arc-anode attachments at different hydrogen concentrations. The concentration of hydrogen was fixed at 0, 30, and 50 vol% in argon arc, corresponding to diffuse, multiple, and constricted arc-anode attachments, respectively, which were observed by using a high-speed camera. The images of the cathode and anode jets were observed with a suitable band-pass filter. The relationship between the area change of the cathode/anode jet and the synchronous voltage/current waveform was studied. By investigating diverse arc-anode attachments, the effect of hydrogen concentration on the features of nickel nanoparticles were investigated, finding that 50 vol% H2 concentration has high productivity, fine crystallinity, and appropriate size distribution. The synthesized nickel nanoparticles were then used as catalysts in a hybrid sodium–air battery. Compared with commercial a silver nanoparticle catalyst and carbon black, nickel nanoparticles have better electrocatalytic performance. The promising electrocatalytic activity of nickel nanoparticles can be ascribed to their good crystallinity, effective activation sites, and Ni/NiO composite structures. Nickel nanoparticles prepared by the direct current (DC) arc discharge method have the potential to be applied as catalysts on a large scale.

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