scholarly journals The Position of Solid Carbon Dioxide in the Triboelectric Series

2019 ◽  
Vol 72 (8) ◽  
pp. 633 ◽  
Author(s):  
Jinyang Zhang ◽  
Simone Ciampi
Keyword(s):  
Carbon Dioxide ◽  
Negative Charge ◽  
Plastic Material ◽  
Indirect Evidence ◽  
Liquid Carbon ◽  
Solid Carbon Dioxide ◽  
Dry Ice ◽  
First Time ◽  
Charge Sign ◽  
Positively Charged

The process of releasing liquid carbon dioxide from a fire extinguisher is accompanied by a strong static charging of the plastic material making up the extinguisher discharge horn. Firefighters often report an electric shock when operating CO2 extinguishers, but the origin of this electrostatic hazard is largely unknown. Here, we begin to investigate this phenomenon, and test the hypothesis of plastic samples being tribocharged on contact with rapidly flowing solid CO2. Using Faraday pail measurements, we show that non-conductive polymers gain a net static charge when brought in and out of contact with dry ice (solid CO2). These measurements of charge sign and magnitude give indirect evidence helping to place solid CO2 for the first time on the triboelectric series. Polydimethylsiloxane (PDMS), polytetrafluoroethylene (PTFE), and polyvinyl chloride (PVC) samples acquire a negative charge when rubbed against dry ice, whereas poly(methyl methacrylate) (PMMA), glass, and nylon surfaces become positively charged. Therefore, we suggest the position of dry ice in the triboelectric series to be close to that of materials with stable cations and unstable anions, possibly locating it between PMMA and PVC.

RAMAN EFFECTS WITH LIQUID AND SOLID CARBON DIOXIDE

1932 ◽  
Vol 7 (6) ◽  
pp. 551-555 ◽  
Author(s):  
J. C. McLennan F.R.S. ◽  
H. D. Smith M.A.
Keyword(s):  
Carbon Dioxide ◽  
Raman Spectrum ◽  
Raman Spectra ◽  
Solid Carbon ◽  
Clear Liquid ◽  
Liquid Carbon ◽  
Solid Carbon Dioxide ◽  
Solid States ◽  
New Type ◽  
First Time

This paper describes in detail methods of obtaining clear liquid carbon dioxide and clear solid carbon dioxide in tubes suitable for light-scattering experiments. A description is given of the new type of mercury arc employed as a source of incident light.For the first time, Raman spectra of carbon dioxide in the liquid and solid states are obtained, and compared with the known Raman spectrum of the substance in the gaseous state.Carbon dioxide is the first substance for which Raman spectra have been obtained for all three states.

coating layer itself, an d at the interface between the coating and the substrate, causes instant fracturing and separation of coating material from the surface. In general, if a coating or contaminant is CHEMICALLY bonded to a surface, dry ice particle blasting will NOT effectively remove the coating. If the bond is PHYSICAL o r MECHANICAL in nature, such as a coating of rubber residue which is "anchored" into the porous surface of an aluminum casting, then there is a good chance that dr y ice blasting will work. Contaminants which are etched, or stained into the surfaces of metals, ceramics, plastics, or other materials typically cannot be removed with dry ice blasting. If the surface of the substrate is extremely porous or rough, providing strong mechanical "anchoring" for the contaminant or coating, dr y ice blasting may not be able to remove all of the coating, or the rate of removal may be too slow to allow dry ice blasting to be cost effective. The classic example of a contaminant that does NOT respond to dry ice blast-ing is RUST. Rust is both chemically and strongly mechanically bonded to steel substrate. Advanced stages of rust must be "chiseled" away with abrasive sand blasting. Only the thin film of powderized "flash" rust on a fresh steel surface can be effectively removed with dry ice blasting. 4.2.1.1. Inductio n (venturi) and direct acceleration blast systems - the effect of the typ e of system on available kinetic energy In a two-hose induction (venturi) carbon dioxide blastin g system, the medium particles are moved from the hopper to the "gun" chamber by suction, where they drop to a very low velocity before being induced into the outflow of the nozzle by a large flow volume of compressed air. Some more advanced two-hose systems employ a small positive pressure to the pellet delivery hose. In any type of two-hose system, since the blast medium particles have only a short distance in which to gain momentum and accelerate to the nozzle exit (usually only 200 to 300 mm), the final particle average velocity is limited to between 60 and 120 meters per second. So, in general, two-hose systems, although not so costly, are limited in their ability to deliver contaminant removal kinetic energy to the surface to be cleaned. When more blasting energy is required, these systems must be "boosted" a t the expense of much more air volume required, and higher blast pressure is re-quired as well, with much more nozzle back thrust, and very much more blast noise generated at the nozzle exit plane. The other type of solid carbon dioxide medium blasting system is like the "pressurized pot" abrasive blasting system common in the sand blasting and Plas-ti c Media Blasting industries. These systems use a single delivery hose from the hopper to the "nozzle" applicator in which both the medium particles and the compressed air travel. These systems are more complex and a little more costly than the inductive two-hose systems, but the advantages gained greatly outweigh the extra initial expense. In a single-hose solid carbon dioxide particle blasting system, sometimes referred to as a "direct acceleration " system, the medium is introduced from the hopper into a single, pre-pressurized blast hose through a sealed airlock feeder. The particles begin their acceleration and velocity increase

2003 ◽  
pp. 162-163
Keyword(s):  
Carbon Dioxide ◽  
Kinetic Energy ◽  
Nozzle Exit ◽  
Compressed Air ◽  
Solid Carbon ◽  
Low Velocity ◽  
Solid Carbon Dioxide ◽  
Sand Blasting ◽  
Dry Ice ◽  
Dry Ice Blasting

scholarly journals Size measurement of dry ice particles produced from liquid carbon dioxide

2012 ◽  
Vol 48 ◽  
pp. 1-9 ◽  
Author(s):  
Yi-Hung Liu ◽  
Graham Calvert ◽  
Colin Hare ◽  
Mojtaba Ghadiri ◽  
Shuji Matsusaka
Keyword(s):  
Carbon Dioxide ◽  
Size Measurement ◽  
Liquid Carbon ◽  
Dry Ice ◽  
Liquid Carbon Dioxide ◽  
Ice Particles

scholarly journals Положительный заряд в КНС-гетероструктурах с межслойным оксидом кремния

2018 ◽  
Vol 52 (10) ◽  
pp. 1220
Author(s):  
В.П. Попов ◽  
В.А. Антонов ◽  
В.И. Вдовин
Keyword(s):  
Oxygen Vacancies ◽  
Silicon Oxide ◽  
Negative Charge ◽  
Silicon Layer ◽  
Silicon Dioxide Layer ◽  
Silicon Oxide Layer ◽  
Order Of Magnitude ◽  
Silicon Based ◽  
First Time ◽  
Positively Charged

AbstractThe continuous transfer of (001)Si layers 0.2–1.7 μm thick by implanted hydrogen to the c -sapphire surface during direct bonding at high temperatures of 300–500°C is demonstrated for the first time. The formation of an intermediate silicon-oxide layer SiO_ x during subsequent heat treatments at 800–1100°C, whose increase in thickness (up to 3 nm) correlates with an increase in the positive charge Q _ i at the heterointerface to ~1.5 × 10^12 cm^–2 in contrast to the negative charge at the SiO_ x /Al_2O_3 ALD heterointerface. During silicon-layer transfer to sapphire with a thermal silicon-dioxide layer, Q _ i decreases by more than an order of magnitude to 5 × 10^10 cm^–2 with an increase in the SiO_2 thickness from 50 to 400 nm, while the electron and hole mobilities barely differ from the values in bulk silicon. Based on these results, a qualitative model of the formation of positively charged oxygen vacancies in a 5-nm sapphire layer near the bonding interface is proposed.

Fabrication and Characterization of Graphene from Solid Carbon Dioxide

2015 ◽  
Vol 1115 ◽  
pp. 418-421 ◽  
Author(s):  
Akhama Arifutzzaman ◽  
Iskandar Yaacob ◽  
M.A. Hawlader ◽  
Md Abdul Maleque
Keyword(s):  
Carbon Dioxide ◽  
Solid Carbon ◽  
Solid Carbon Dioxide ◽  
Complete Combustion ◽  
Dry Ice ◽  
Black And White ◽  
Transmission Electron ◽  
Product Characterization ◽  
Fabrication And Characterization

Graphene was fabricated by a well-known technique of ignition of magnesium (Mg) metal ribbon in solid carbon dioxide. Two dry ice slabs were used as carbon source for the production of graphene. A hemispherical cavity of about 3-4 cm diameter was carved on surfaces of both dry ice slabs. About 0.5g of Mg ribbon was burnt and immediately placed into the dry ice cavity. It was then covered up by another carved slab of dry ice. After complete combustion, mixture of black and white residues was formed. It was then recovered. 20 ml of 1 M HCl acid was added to the product mixture. Reaction of HCl with MgO and unburned Mg formed MgCl2 which was then washed away by deionized water. The isolated carbon material was separated as product. Characterization of the product was performed using optical microscopy (OM), where images showed the presence of sheet-like light gray objects. Field emission scanning electron microscopy (FESEM) and transmission electron microscope (TEM) analyses revealed the presences of graphene. The lateral length of the sheet was about 3-3.5 μm and the surface area was about 3-5.5 μm2 using images analysis software.

Characteristics of Dry Ice Particles Produced by Expanding Liquid Carbon Dioxide and its Application for Surface Cleaning

2012 ◽  
Vol 508 ◽  
pp. 38-42 ◽  
Author(s):  
Yi Hung Liu ◽  
Shuji Matsusaka
Keyword(s):  
Carbon Dioxide ◽  
Surface Cleaning ◽  
Particle Removal ◽  
Liquid Carbon ◽  
Dry Ice ◽  
Liquid Carbon Dioxide ◽  
Ice Particles ◽  
Median Diameter ◽  
Mass Median ◽  
Mass Median Diameter

The characteristics of dry ice particles produced by expanding liquid carbon dioxide and its application for surface cleaning have been studied experimentally. The production of the dry ice particles was based on the Joule-Thomson effect. The ejected dry ice particles were observed using a high-speed microscope camera. Through digital image processing, the particle size and particle velocity in the jet were analyzed. To in-situ measure the size distribution of the dry ice particles, a laser diffraction method was used. The experimental results showed that the primary dry ice particles ejected from the expansion nozzle were about 1 μm in mass median diameter. The presence of a thermally insulated tube at the outlet of the nozzle enhanced the agglomeration of the particles, whereby agglomerates of about 100 μm in mass median diameter were formed. The performance of dry ice jet for removing fine particles adhering to surfaces was also evaluated using microscopic observation. It was found that the particle removal process consists of two stagesslow removal stage and rapid removal stagethat are related to the jet temperature.

Evaluation of the Quality of Seer Fish(Scomberomorus commersonii)Stored in Dry Ice (Solid Carbon Dioxide)

2003 ◽  
Vol 12 (2) ◽  
pp. 61-72 ◽  
Author(s):  
M. Sasi ◽  
G. Jeyasekaran ◽  
S. A. Shanmugam ◽  
R. Jeya Shakila
Keyword(s):  
Carbon Dioxide ◽  
Solid Carbon ◽  
Solid Carbon Dioxide ◽  
Dry Ice ◽  
Seer Fish
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