Chemical erosion of graphite due to simultaneous H+ and O+ irradiation. by Allen Y. K. Chen Download PDF EPUB FB2
Chemical Erosion of Graphite Due to Simultaneous and Of Irradiation by Allen Y.K- Chen, Department of Aerospace Studies, University of Toronto submitted in conformity with the requirement for the degree of Ph.D.
() ABSTRACT Graphite is one of the prime cmdidates for first-wall use in Author: Allen Y. Chen. Extensive investigations of the chemical erosion of graphite have been performed in our laboratory under conditions of simultaneous bombardment by O 2 + and H 3 + ions, using an independently controlled high-flux, low-energy, mass-analyzed dual-beam ion accelerator system, e.g., Refs.Based on results of previous studies of methane formation in graphite under energetic H + and H 3 Cited by: 1.
Introduction. With such advantages as a low atomic number, excellent thermomechanical properties and high thermal conductivity, graphite is a widely used material for plasma facing components in thermonuclear fusion major disadvantage of graphite, however, is its high erosion yield due to chemical erosion by hydrogen ion bombardment, especially at elevated by: 6.
Nuclear graphite is any grade of graphite, usually synthetic graphite, specifically manufactured for use as a moderator or reflector within a nuclear te is an important material for the construction of both historical and modern nuclear reactors, due to its extreme purity and its ability to withstand extremely high te has also recently been used in nuclear.
Measurements of chemical erosion of ATJ graphite by low energy D 2 + impact Article in Journal of Nuclear Materials (1) March with 21 Reads How we measure 'reads'.
Chemical sputtering of carbon films by simultaneous irradiation with argon ions and molecular oxygen Article in New Journal of Physics 10(9) September with 60 Reads. nuclear reactor. Graphite is an important material for the construction of both historical and modern nuclear reactors, due to its extreme purity and its ability to withstand extremely high temperatures and high irradiation doses (fast neutrons).
Reactor-grade graphite must File Size: 1MB. the chemical erosion measurements difﬁcult. In addition, another goal of the experiment was to look at chemical erosion due to low energy plasma bombardment of the target instead of ion beam irradiation (which is typical of IIAX facility).
For this purpose, a new chamber is built for chemical erosion measurements. The. () Graphite planes () Graphite planes () Graphite planes x 10 20 -e cm -2 x 10 20 e cm -2 x 10 e - cm 2 Quantification of radiation damageFile Size: 2MB.
Chemical erosion of graphite due to simultaneous H+ and O+ irradiation. book However due to carbon’s high affinity for oxygen, if these reactive oxidising species impinge on a graphite surface they gasify it to carbon monoxide. This process is known as radiolytic corrosion. Under irradiation carbon dioxide breaks down into oxidising ions and free radicals (1).
The effects of natural chemical impurities and crystallite orientation on the erosion behavior of several artificial graphites have been determined in a Mach 2 airstream with a stagnation-point pressure of atm and a nominal total enthalpy of MJ/kg. After washing, milling and calcining, the graphite rods recycled from waste dry batteries were used as raw material to prepare expandable graphite by chemical oxidation (using acetic anhydride as inserting and potassium dichromate as oxidant), the expanded graphite was prepared from the obtained expandable graphite by microwave radiation (MW) at W for characterization of Cited by: 3.
Other instrumental analysis techniques are available, capable of simultaneous quantitative analysis of 76 stable elements in a single run, with detectability limits in the parts per million range. Standards are currently being developed for elemental analysis of impurities in graphite using glow discharge mass spectrometry (GDMS), inductively coupled plasma optical emission spectroscopy.
The chemical state of lithiated graphite is found to change upon deuterium irradiation indicating the formation Li-O-D, manifest at ± eV. Lithium-deuterium interactions are also manifest in the C 1s photoelectron energy range and show Li-C-D interactions at ± by: In addition to the seal applications mentioned above, molded graphite has many applications in areas where chemical resistance is the major factor.
Such applications are found in chemical reactors, heat exchangers, steam jets, chemical-vapor deposition equipment, and cathodic-protection anodes for pipelines, oil rigs, DC-power lines, and highway and building construction.
It is worth noting that the peak position of G band of GO is slightly larger than pristine graphite/graphene ( cm −1) due to chemical-functional-group-induced hole doping effect. When pressure increases, both G and D′ bands linearly shift to higher wavenumber, and the peak positions blueshift to and cm −1 at the maximum Cited by: the erosion rates of graphite composites when exposed to supersonic hydrogen atmosphere.
2 We have developed a theo-retical model based on laminar boundary layer flow equasions to predict these erosion rates. Some details of the experimental setup can be found. The status of graphite irradiation induced creep strain prediction is reviewed and major creep models are described.
The ability of the models to quantitatively predict the irradiation induced creep strain of graphite is reported. Potential mechanisms of in-crystal creep are reviewed as are mechanisms of pore generation under stress. The case for further experimental work is made and the Cited by: 8.
It is demonstrated experimentally that an irradiation-induced transformation of planar as well as curved graphite to diamond can be carried out without applying pressure. A specimen containing both graphite and diamond is irradiated at high temperature with an electron beam in an electron by: Using Intercalation to Simulate Irradiation Damage of Nuclear Graphite Lewis Luyken A thesis submitted to the University of Manchester for the degree of Doctor of Philosophy in the Faculty of Engineering and Physical Sciences.
School of Mechanical, Aerospace and Civil Engineering The University of Manchester. * Corresponding authors a Queensland Micro- and Nanotechnology Centre, Griffith University, Nathan, Australia E-mail: @ Fax: +61 7 Cited by: TEM image of highly oriented pyrolytic graphite (HOPG) irradiated with 20 keV D + at K.
The left hand side area (a) of the image is a part of the specimen covered by a mesh wire and the right hand side area (c) is a part irradiated to a dose of × 10 21 ions/m ed area diffraction patterns corresponding to the areas (a), (b) and (c) are given below the by: Chemical analysis of graphene oxide ﬁlms after heat and chemical treatments by X-ray photoelectron and Micro-Raman spectroscopy Dongxing Yanga, Aruna Velamakannia,Gu¨lay Bozoklub, Sungjin Parka, Meryl Stollera, Richard D.
Pinera, Sasha Stankovichc, Inhwa Junga, Daniel A. Fieldd, Carl A. Ventrice Jr.d,*, Rodney S. Ruoffa,* aDepartment of Mechanical Engineering, University of Texas at Austin. Polycrystalline graphene grown by chemical vapor deposition (CVD) on metals and transferred onto arbitrary substrates has line defects and disruptions such as wrinkles, ripples, and folding that adversely affect graphene transport properties through the scattering of the charge carriers.
It is found that graphene assembled with metal nanowires (NWs) dramatically decreases the resistance of. It is recommended that a graphite model that includes neutron fluence and the initial value of the elastic modulus be used as an approximation for dimensional changes of graphite samples.
2 Author: V. Nikolaenko, V. Kuznetsov, P. Platonov, O. Chugunov. Graphite oxide (GO) and its derivatives have been studied using 13C and 1H NMR. The 13C NMR lines at 60, 70, and ppm are assigned to C−OH, C−O−C, and >CCCC. Urea-assisted aqueous exfoliation of graphite was found to be more efficient than exfoliation in N,N-dimethylformamide (DMF), and high-quality graphene was obtained with a yield up to %.
The mechanism in which a primary amine facilitates aqueous exfoliation was. Conforms to HazCom /United States SAFETY DATA SHEET Poco Graphite Synthetic Graphite Manufacturing tooling, fixtures, other industrial manufacturing components. POCO Graphite, Inc. An Entegris Company Old Greenwood Road Decatur, TexasEXT (8am - 4pm CT, Mon - Fri)File Size: 1MB.
The isolation of graphene nearly a decade ago has unleashed an immense wave of research into the field, revealing many of its exceptional mechanical, physical, and chemical properties (1, 2).Subsequently, a slew of potential applications for graphene have been suggested, ranging from electrosensing (), sustainable energy production and storage (4 –6), novel composites (), and Cited by: LIAO ET 5™ NO.
2 ™ – ™ Janu C American Chemical Society Aqueous Only Route toward Graphene from Graphite Oxide Ken-Hsuan Liao, Anudha Mittal, Shameek Bose, Christopher Leighton, K. Andre Mkhoyan,* and. Graduate Thesis Or Dissertation Study of graphite-polyurethane composite thin film electrodes for their use in electrochemical antifouling systems Public Deposited.
Analytics × Add to Cited by: 1. Nanocrystalline graphite enables new class of harsh environment electronics More from Materials and Chemical Engineering. We do not guarantee individual replies due to extremely high.Therefore, the alkalinity is due to HCO3- and [HCO 3- ] = × M.
Substitution into the expression for Ka1 shows that at pH and [HCO3-] = × M, the value of [CO2(aq)] is × M, somewhat higher than the value that arises from water in equilibrium with atmospheric air, but readily reached due to the presence of.