Carbon nanostructure growth: new application of magnetron discharge

2021 ◽  
Vol 109 (1) ◽  
pp. 17-25
Author(s):  
A. Breus ◽  
S. Abashin ◽  
O. Serdiuk
Keyword(s):  
Carbon Nanostructures ◽  
Large Scale ◽  
Glow Discharge Plasma ◽  
Scale Production ◽  
Plasma Reactors ◽  
Carbon Nanostructure ◽  
Magnetron Discharge ◽  
Sputtering Deposition ◽  
High Productivity ◽  
Race Track

Purpose: The application of a common magnetron discharge to the growth of carbon nanostructures is studied. The simplicity of the proposed technique can be beneficial for the development of new plasma reactors for large-scale production of carbon nanostructures. Design/methodology/approach: Graphite cathode was treated by carbon-containing powder accelerated by use of nozzle, and then aged in hydrogen. Superposition of glow and arc discharges was obtained, when putting the cathode under the negative biasing with respect to the walls of a vacuum chamber. The pulsed discharge was preserved through the whole time of treatment. This process was explained in terms of interaction of glow discharge plasma with a surface of the cathode made of non-melting material. Findings: The plasma treatment resulted in generation of the diverse nanostructures confirmed by SEM and TEM images. Spruce-like nanostructures and nanofibers are observed near the cathode edge where the plasma was less dense; a grass-like structure was grown in the area of “race-track”; net-like nanostructures are found among the nanofibers. These findings allow concluding about the possible implementation of the proposed method in industry. Research limitations/implications: The main limitation is conditioned by an explosive nature of nanostructure generation in arcs; thus, more elaborate design of the setup should be developed in order to collect the nanospecies in the following study. Practical implications: High-productivity plasma process of nanosynthesis was confirmed in this research. It can be used for possible manufacturing of field emitters, gas sensors, and supercapacitors. Originality/value: Synthesis of carbon nanostructures is conducted by use of a simple and well-known technique of magnetron sputtering deposition where a preliminary surface treatment is added to expand the production yield and diversity of the obtained nanostructures.

scholarly journals DISCHARGE CHARACTERISTICS OF THE MAGNETRON SYSTEM FOR SPUTTERING, DEPOSITION, AND NANOTECHNOLOGY APPLICATIONS

2020 ◽  
pp. 72-79
Author(s):  
Andrii Breus ◽  
Oleksii Serdiuk ◽  
Vasyl Ruzaikin ◽  
Oleg Baranov
Keyword(s):  
Magnetron Sputtering ◽  
Carbon Nanostructures ◽  
Large Scale ◽  
Arc Discharge ◽  
Expanded Graphite ◽  
Time Interval ◽  
Scale Production ◽  
Magnetron Discharge ◽  
Sputtering Deposition ◽  
Graphite Cathode

Magnetron sputtering is known for years as a powerful tool for coating deposition of cutting tools and machine parts. However the experimental measurements of the magnetron discharge parameters are still necessary to provide a consumer of the magnetron system with the reliable characteristics. A voltage-current relation is the most applied characteristic of the discharge, and it is described as the power low of a type U = U0 + aIn, where U and I are the voltage drop and the discharge current, respectively, and U0 and n are constant. First part of the research is dedicated to the experiments conducted in the magnetron setup provided with the titanium cathode in a vacuum chamber filled with argon or argon-nitrogen mixture, and the constants are determined for the particular geometry of the magnetron sputtering system. The obtained results can be used to choose the operation modes for the traditional applications of the magnetron discharge such as ion cleaning and heating of the non-magnetic workpieces arranged on the cathode, as well as for the sputtering deposition of the titanium and titanium nitride coatings on the surfaces of the workpieces located above the magnetron cathode. In the next part of the research the novel application of the magnetron for production of carbon nanostructures is considered. For the purpose, a layer of expanded graphite is arranged on the magnetron cathode, and the discharge is initiated in oxygen atmosphere. It was found that for the time interval of a few hours the discharge is described as a superposition of the typical magnetron glow with arc spot generation, and the intensity of the arcs is not decreased with time. At that, the arc initiation was accompanied with the formation of clusters of the graphite cathode. The process is explained in terms of the cathode spot generation at the interaction of the arc plasma with the non-melting material. This process can be beneficial for the development of the plasma reactors for the large-scale production of the carbon species at the low gas pressures suitable for the magnetron discharge operation. Thus, the magnetron sputtering systems provided with the expanded graphite cathode can be considered as the tool to grow carbon nanospecies in the arc discharge cathode spots.

Carbon Cones - a Structure with Unique Properties

2007 ◽  
Vol 1057 ◽  
Author(s):  
Geir Helgesen ◽  
Kenneth D. Knudsen ◽  
Jean Patrick Pinheiro ◽  
Arne T. Skjeltorp ◽  
Eldrid Svåsand ◽  
...  
Keyword(s):  
Carbon Black ◽  
Carbon Nanostructures ◽  
Large Scale ◽  
The Other ◽  
Current Status ◽  
Scale Production ◽  
Plasma Process ◽  
Large Scale Production ◽  
Nanocarbon Materials ◽  
Forms Of Carbon

ABSTRACTLarge-scale production of perfect conical carbon nanostructures that are fundamentally different from the other nanocarbon materials, such as buckyballs and nanotubes, can be made using the so-called Kvaerner Carbon Black & Hydrogen Process. This involves pyrolysis of hydrocarbons using a torch plasma process. The carbon cones that occur appear in five distinctly different forms. In addition, disk-shaped particles may be produced. Here we report about the current status for the experimental research and theoretical modeling of these particles, which have properties different from the other known forms of carbon.

scholarly journals Replacement of a Metabolic Pathway for Large-Scale Production of Lactic Acid from Engineered Yeasts

1999 ◽  
Vol 65 (9) ◽  
pp. 4211-4215 ◽  
Author(s):  
Danilo Porro ◽  
Michele M. Bianchi ◽  
Luca Brambilla ◽  
Rossella Menghini ◽  
Davide Bolzani ◽  
...  
Keyword(s):  
Lactic Acid ◽  
Large Scale ◽  
Kluyveromyces Lactis ◽  
Lactic Acid Production ◽  
Pyruvate Decarboxylase ◽  
Polymer Materials ◽  
Efficient Production ◽  
Scale Production ◽  
High Productivity ◽  
Large Scale Production

ABSTRACT Interest in the production of l-(+)-lactic acid is presently growing in relation to its applications in the synthesis of biodegradable polymer materials. With the aim of obtaining efficient production and high productivity, we introduced the bovinel-lactate dehydrogenase gene (LDH) into a wild-type Kluyveromyces lactis yeast strain. The observed lactic acid production was not satisfactory due to the continued coproduction of ethanol. A further restructuring of the cellular metabolism was obtained by introducing the LDH gene into aK. lactis strain in which the unique pyruvate decarboxylase gene had been deleted. With this modified strain, in which lactic fermentation substituted completely for the pathway leading to the production of ethanol, we obtained concentrations, productivities, and yields of lactic acid as high as 109 g liter−1, 0.91 g liter−1 h−1, and 1.19 mol per mole of glucose consumed, respectively. The organic acid was also produced at pH levels lower than those usual for bacterial processes.

scholarly journals A pioneering healthcare model applying large-scale production concepts: Principles and performance after more than 11,000 transplants at Hospital do Rim

2016 ◽  
Vol 62 (7) ◽  
pp. 664-671 ◽  
Author(s):  
José Medina Pestana
Keyword(s):  
Health Care ◽  
Large Scale ◽  
Organ Procurement ◽  
Clinical Results ◽  
Scientific Management ◽  
Scale Production ◽  
High Productivity ◽  
Unified Health System ◽  
Healthcare Model ◽  
And Performance

Summary The kidney transplant program at Hospital do Rim (hrim) is a unique healthcare model that applies the same principles of repetition of processes used in industrial production. This model, devised by Frederick Taylor, is founded on principles of scientific management that involve planning, rational execution of work, and distribution of responsibilities. The expected result is increased efficiency, improvement of results and optimization of resources. This model, almost completely subsidized by the Unified Health System (SUS, in the Portuguese acronym), has been used at the hrim in more than 11,000 transplants over the last 18 years. The hrim model consists of eight interconnected modules: organ procurement organization, preparation for the transplant, admission for transplant, surgical procedure, post-operative period, outpatient clinic, support units, and coordination and quality control. The flow of medical activities enables organized and systematic care of all patients. The improvement of the activities in each module is constant, with full monitoring of various administrative, health care, and performance indicators. The continuous improvement in clinical results confirms the efficiency of the program. Between 1998 and 2015, an increase was noted in graft survival (77.4 vs. 90.4%, p<0.001) and patient survival (90.5 vs. 95.1%, p=0.001). The high productivity, efficiency, and progressive improvement of the results obtained with this model suggest that it could be applied to other therapeutic areas that require large-scale care, preserving the humanistic characteristic of providing health care activity.

scholarly journals Biomedical Alloys and Physical Surface Modifications: A Mini-Review

Materials ◽  
2021 ◽  
Vol 15 (1) ◽  
pp. 66
Author(s):  
Xinxin Yan ◽  
Wei Cao ◽  
Haohuan Li
Keyword(s):  
Surface Modification ◽  
Physical Vapor Deposition ◽  
Large Scale ◽  
Thermal Spraying ◽  
Surface Modifications ◽  
Glow Discharge Plasma ◽  
Scale Production ◽  
Coating Materials ◽  
Physical Surface ◽  
Large Scale Production

Biomedical alloys are essential parts of modern biomedical applications. However, they cannot satisfy the increasing requirements for large-scale production owing to the degradation of metals. Physical surface modification could be an effective way to enhance their biofunctionality. The main goal of this review is to emphasize the importance of the physical surface modification of biomedical alloys. In this review, we compare the properties of several common biomedical alloys, including stainless steel, Co–Cr, and Ti alloys. Then, we introduce the principle and applications of some popular physical surface modifications, such as thermal spraying, glow discharge plasma, ion implantation, ultrasonic nanocrystal surface modification, and physical vapor deposition. The importance of physical surface modifications in improving the biofunctionality of biomedical alloys is revealed. Future studies could focus on the development of novel coating materials and the integration of various approaches.

Carbon Nanostructures by Using FeCl3 as Catalyst Precursor

2007 ◽  
Vol 26-28 ◽  
pp. 1137-1140
Author(s):  
Hong Dan Zhang ◽  
Xiao Ping Zou ◽  
Jin Cheng ◽  
Fei Li ◽  
Peng Fei Ren
Keyword(s):  
Carbon Nanotubes ◽  
Carbon Nanostructures ◽  
Large Scale ◽  
Structural Changes ◽  
Low Cost ◽  
Precursor Solution ◽  
Copper Plate ◽  
Catalyst Precursor ◽  
Scale Production ◽  
Carbon Nanowires

Carbon nanotubes and carbon nanowires were synthesized by ethanol catalytic combustion (ECC) technique, using FeCl3 solution as a catalyst precursor. Applying the 0.01 mol/l, 0.1 mol/l and 1 mol/l FeCl3 as catalyst precursor solution to the copper plate, carbon nanotubes and carbon nanowires were synthesized. The effect of concentration on growth and structural changes of the as-grown nanomaterials are illustrated and discussed. This technique has advantages of low cost, large scale production and flexible reaction conditions, etc. This technique can be used to synthesize carbon nanotubes and nanowires on metal substrate directly. This technique also has potential applications for fabricating nano-electrical devices.

scholarly journals Studies and Practice of Geometrical Test Procedures & Reconditioning of CNC Lathe Machine Tool

2021 ◽  
Vol 2070 (1) ◽  
pp. 012228
Author(s):  
Jerin Beno ◽  
M VeeraBhadra Rao ◽  
Sunil Kumar Das
Keyword(s):  
Machine Tool ◽  
Large Scale ◽  
Scale Production ◽  
Test Procedures ◽  
High Productivity ◽  
Large Scale Production ◽  
Cnc Lathe ◽  
Lathe Machine ◽  
Manufacturing Technologies ◽  
Indian Industries

Abstract Machining Centres have been major production units for many decades with desired levels of accuracy, economy in costs of production and ease of control. Though new disruptive technologies such as rapid manufacturing, near net shape manufacturing technologies are replacing these machining units, still small and medium Indian Industries go with the conventional ways of large-scale production using conventional and classical machining approaches. With huge setups in place, such machines with high productivity demands, require stringent parts alignment tests frequently from time to time, referred to as Geometrical or Alignment tests to enable accurate finishing and machining of parts and smooth and uninterrupted production. This paper puts forth some basic Geometrical Tests performed on SB CNC 60 Lathe Machine Tool unit, identifying major deviations measurements and reconditioning the machine parts. The main objective of running such tests is to prevent breakdown of the machine and ensure safety working when handling older and heavier conventional machines.

The Growth of Carbon Nanostructure on the Mechanical-Milling-Derived Catalyst Precursors

2005 ◽  
Vol 23 ◽  
pp. 383-386
Author(s):  
B.H. Liu ◽  
J. Ding ◽  
Z.L. Dong ◽  
Zeng Yong Zhong ◽  
Jian Yi Lin ◽  
...  
Keyword(s):  
Mechanical Milling ◽  
Carbon Nanostructures ◽  
Large Scale ◽  
Hydrogen Reduction ◽  
Water Soluble ◽  
High Yield ◽  
Carbon Nanostructure ◽  
High Hydrogen ◽  
Washing Process ◽  
Carbon Encapsulated Metal Nanoparticles

Mechanical milling was employed to prepare the nanocomposite precursors for the catalytic growth of carbon nanostructures. For alumina substrates, our study showed that mechanical-millingderived catalyst precursors possessed high hydrogen reduction efficiency that in turn enabled the high yield of CNTs. The alloying effects presented by the mechanical milling could accelerate the substitutional reactions between the parent oxides and thus the quality of CNTs was apparently improved. In addition, by using water-soluble substrates such as NaCl, we realized large-scale formation of carbon-encapsulated metal nanoparticles (CEMNs) that can be completely separated by a simple washing process. It was found that the morphologies of as-obtained carbon nanostructures were strongly dependent on the substrate effects. By selecting different salt substrates, we can strategically change the morphologies of the as-obtained nanostructures, from CNTs to CEMNs and the intermediate state between CNTs and CEMNs, such as quasi-nanocages.

AGRICULTURAL PRODUCTION OF CA DONG PEOPLE IN RESETTLEMENT AREA OF TRANH RIVER HYDROPOWER NUMBER 2: CURRENT SITUATION AND IMPACT FACTORS

2020 ◽  
Vol 9 (2) ◽  
Author(s):  
Bùi Thị Bích Lan
Keyword(s):  
Social Relations ◽  
Agricultural Production ◽  
Large Scale ◽  
Transition Process ◽  
Impact Factors ◽  
Small Scale ◽  
Scale Production ◽  
Technical Application ◽  
Production Models ◽  
Role Of The State

In Vietnam, the construction of hydropower projects has contributed significantly in the cause of industrialization and modernization of the country. The place where hydropower projects are built is mostly inhabited by ethnic minorities - communities that rely primarily on land, a very important source of livelihood security. In the context of the lack of common productive land in resettlement areas, the orientation for agricultural production is to promote indigenous knowledge combined with increasing scientific and technical application; shifting from small-scale production practices to large-scale commodity production. However, the research results of this article show that many obstacles in the transition process are being posed such as limitations on natural resources, traditional production thinking or the suitability and effectiveness of scientific - technical application models. When agricultural production does not ensure food security, a number of implications for people’s lives are increasingly evident, such as poverty, preserving cultural identity, social relations and resource protection. Since then, it has set the role of the State in researching and building appropriate agricultural production models to exploit local strengths and ensure sustainability.

I. S. A. Baud. Forms of Production and Women's Labour: Gender Aspects of Industrialisation in India and Mexico. New Delhi: Sage Publications. 1992. 321 pp.Hardbound. Price: Indian Rs 295.00.

1993 ◽  
Vol 32 (1) ◽  
pp. 129-131
Author(s):  
Naureen Talha
Keyword(s):  
Large Scale ◽  
Indian Society ◽  
New Delhi ◽  
Scale Production ◽  
Female Labour ◽  
Self Employment ◽  
Commodity Production ◽  
Large Scale Production ◽  
Mexican Society ◽  
Small Production

The literature on female labour in Third World countries has become quite extensive. India, being comparatively more advanced industrially, and in view of its size and population, presents a pictures of multiplicity of problems which face the female labour market. However, the author has also included Mexico in this analytical study. It is interesting to see the characteristics of developing industrialisation in two different societies: the Indian society, which is conservative, and the Mexican society, which is progressive. In the first chapter of the book, the author explains that he is not concerned with the process of industrialisation and female labour employed at different levels of work, but that he is interested in forms of production and women's employment in large-scale production, petty commodity production, marginal small production, and self-employment in the informal sector. It is only by analysis of these forms that the picture of females having a lower status is understood in its social and political setting.

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