Pulsed Cold Plasma Research Articles

A novel, green, low-cost regeneration method for surface enhanced raman scattering (SERS) solid substrates based on nanosecond pulsed cold plasma technology

Surface enhanced raman scattering (SERS) technique has been widely implemented for the detection/quantification of numerous compounds. The development of reusable SERS substrates through regeneration is a constant concern of scientists in the field, related to the sustainability of the method. Cold atmospheric plasma (CAP) is an advantageous green method well-known for its effectiveness towards the successful degradation of organic molecules and materials’ activation/modification. In the present study, we explored for the first time nanosecond pulsed dielectric barrier discharge (NSP-DBD) plasma as a rapid, energy efficient method for SERS solid substrates regeneration, implemented either directly in the gas or in the liquid phase as well as through immersion of the substrates in plasma activated water (PAW). We investigated the critical cold plasma factors (e.g. feeding gas, plasma treatment and retention time) in order to propose the most cost-effective alternative and shed light on the underlying regeneration mechanisms. The different SERS analysis case scenarios (analyte's class , concentration andcross check) were considered, in order to simulate real SERS measurements conditions/requirements. In practical terms, such an approach will contribute to a significant reduction of the detection costs, revealing the NSP-DBD process as a flexible, fast, green, effective and low-cost solution towards the SERS substrates regeneration.

Enhancing Shelf Life of Bananas by Using Atmospheric Pressure Pulsed Cold Plasma Treatment of the Storage Atmosphere

Enhancing Shelf Life of Bananas by Using Atmospheric Pressure Pulsed Cold Plasma Treatment of the Storage Atmosphere

Experimental study on bacteria disinfection using a pulsed cold plasma jet with helium/oxygen mixed gas

Cold atmospheric plasma jet is widely used in many fields due to the reactive oxygen species and low temperature for heat-sensitive products. This paper presents the inactivation of bacteria via a pulsed plasma jet with He/O2 mixed gas. To evaluate the disinfection performance, Staphylococcus aureus was used as an indicator bacteria for experiments. When the plasma jet dealt with agar plates spraying bacteria, it was found that mixed gas has a better performance than pure inert gas, indicated by the disinfection area. The increment of oxygen gas addition was beneficial to the disinfection ability of the plasma jet, while the gas had an opposite effect on the length of jet production. The experiments showed the efficacy of Staphylococcus aureus disinfection could reach up to 99.47% via a helium/oxygen (2%) plasma jet.

Pulsed cold plasma-induced blood coagulation and its pilot application in stanching bleeding during rat hepatectomy

This paper presents plasma-induced blood coagulation and its pilot application in rat hepatectomy by using a home-made pulsed cold plasma jet. Experiments were conducted on blood coagulation in vitro, the influence of plasma on tissue in vivo, and the pilot application of rat hepatectomy. Experimental results show that the cold plasma can lead to rapid blood coagulation. Compared with the control sample, the plasma-induced agglomerated layer of blood is thicker and denser, and is mostly composed of broken platelets. When the surface of the liver was treated by plasma, the influence of the plasma can penetrate into the liver to a depth of about 500 μm. During the rat hepatectomy, cold plasma was proved to be effective for stanching bleeding on incision. No obvious bleeding was found in the abdominal cavities of all six rats 48 h after the hepatectomy. This implies that cold plasma can be an effective modality to control bleeding during surgical operation.

Multiphysics simulation of pulsed cold plasma arc rotation for enhanced hydrogen harvesting

Pulsed cold plasma reforming is a novel method to harvest hydrogen from hydrocarbons. The harvested hydrogen can feed a fuel cell for distributed generation of electricity in a stationary or mobile platform. The cold plasma arc is generated by a pulsating high voltage waveform. The arc rotates in the magnetic field caused by a ring permanent magnet, thus increasing the collision area between the arc and the fuel. Due to the difficulties of measurement of plasma properties such as ion and electron temperature without disturbing the plasma, multiphysics simulation is a key step in the design of electrodes, thereby increasing the hydrogen harvest rate in the syngas. In this paper, a 3D multiphysics simulation including fluid dynamics, thermal response, and electromagnetic fields has been carried out to assist in selection of the permanent magnet. Experiments were carried out to verify the simulation results. The 3D multiphysics simulation is demonstrated to be an effective tool to assist in the design of the reformer. The hydrogen harvest rate has been improved from 58.7% to 67.8% with the introduction of the magnet.

The Plasma Pencil: A Source of Hypersonic Cold Plasma Bullets for Biomedical Applications

Cold plasma jets and their interaction with materials and media have recently been very active research topics. The low gas temperature enables applications in various fields, including medicine. In bioapplications, for example, it involves radiation and reactive species created by the plasma jet to modify or kill prokaryotic cells (bacteria) or eukaryotic cells (mammalian cells). In this paper, we present photographs of a pulsed cold plasma plume/jet that turned out to be a series of high-velocity plasma ldquobulletsrdquo or ldquopackets.rdquo These bullets travel at hypersonic speeds, and these transport with them chemically reactive species and deliver them to the surface of samples under treatment.

Modification of a Carbon Electrode Surface by Cold Plasma Treatment for Electric Double Layer Capacitors

ABSTRACTActivated carbon fiber cloth (ACFC) electrodes whose surface was modified by “pulsed cold plasma”, i.e., low-temperature plasma generated by a pulsed electric power in argon-oxygen mixed gas at a reduced pressure, were applied to electric double layer (EDL) capacitors with an organic electrolyte composed of propylene carbonate and tetraethylammonium tetrafluoroborate (TEABF4). The treatment of the ACFC electrodes with the pulsed cold plasma increased total capacitance in the EDL capacitors. The observed increase in the total capacitance was ascribed mainly to an ascertained increase in capacitance of a negative ACFC electrode involving TEA+cation adsorption/desorption with the cold plasma treatment. No obvious increase in capacitance of a positive ACFC electrode involving BF4- anion adsorption/desorption was observed with the plasma treatment. The chemical and electrochemical characteristics of a treated ACFC interface were found to be favorable for TEA+cation adsorption/desorption.