Ali Gulec

One Atmosphere Uniform Glow Discharge Plasma

Summary form given only. Production of a stable atmospheric pressure glow discharge is always problem. Parallel plate dielectric barrier system is built in order to examine the physics of the atmospheric pressure discharge. The gap distance, frequency and voltage characteristics of atmospheric pressure plasma discharge are experimentally investigated with and without the addition of the helium. Optical characteristics, time-dependent and spatiallv resolved ICCD pictures will be given.

Complementary all Solid State Electrochromic Devices Using Carboxymethyl Cellulose Based Electrolytes

The paper presents the results of the research on a new polymer-membrane and gel electrolytes for electrochromic devices. A complementary solid-state electrochromic device consisting of cathodically coloring working electrode of WO3 and anodically coloring counter electrode of NiO films is prepared to compare the effects of gel or membrane forms of carboxymethyl cellulose (CMC) polymer electrolyte on the electrochromic properties of devices. The performance evaluations of the complementary solid-state electrochromic devices indicate good reversibility, low power consumption of ±3 V in colored state, high variation of transmittance changing of 64% in gel electrolyte, and lower 7% in membrane electrolyte and good memory effect under open-circuit conditions. CMC based electrolytes can be used as an ion-conducting medium and be a good candidate for complementary electrochromic devices owing to, the improved properties as well as its cheapness.

Atmospheric Pressure 2.45-GHz Microwave Helium Plasma

A waveguide-based microwave plasma system was built using a resonant cavity and a quartz tube. 2.45 GHz 850 W magnetron was used to obtain helium discharge without an igniter. The temporal images of discharge were recorded on microsecond time scales using an intensified charge-coupled device camera. The excitation temperature was calculated as 3385 K using the helium lines, which were obtained from emission spectrum of the discharge. The gas temperature was measured as 1208 K by a thermocouple.

Surface properties of radio frequency plasma treated wool and denim fabrics

Purpose The purpose of this paper was to investigate the effects of hydrochloric acid (HCl), hydrazine, methyl methacrylate, styrene and hexamethyldisiloxane by radio-frequency (rf) plasma graftings on surface properties of wool and denim fabrics. Design/methodology/approach During plasma treatments, processing time was varied under optimized plasma conditions (50 W, rf: 13.56 MHz). All fabrics were comprehensively investigated by means of scanning electron microscopy-energy dispersive X-ray spectroscopy and contact angle measurements. Findings The experimental data shows that the rf-plasma processing has important effect on the wettability properties of wool and denim fabrics. The results indicated that HCl plasma treatment significantly improves the hydrophilicity of wool and denim fabrics. Originality/value The research on wool and denim fabric treatment by plasma is original.

Atmospheric pressure plasma pen for surgical purposes

Atmospheric pressure cold plasmas are used in sterilization, cutting and coagulation without damaging living tissues and cells. The preliminary studies on the production of the plasma pen which will allow cutting and coagulation at lower temperature than the conventional electrosurgery methods are presented. Intended power supply, pen design and manufacture are made. The results related to the first in vitro experiments carried out by the pen are given.

Inductively coupled plasma for graphene production

This study is investigating the direct growth of graphene on a membrane filter and a copper surface by injecting ethanol vapor into an inductively coupled plasma (ICP) at atmospheric pressure. Low temperature (<;1000) graphene production is possible by an ICP plasma [1]. The discharge chemical mechanism will be analyzed by optical emission spectrum. The effects of the temperature and the plasma power on graphene sheets will be analyzed by SEM, AFM and Raman spectra.

Graphene synthesis by PECVD

PECVD method is attractive for SWCNTsyntheis due to the better control and it is providing appropriate environment for decomposition of carbon feed-stocks at a lower temperature (<;800) [1]. To produce graphene sheets on a copper surface the rf plasma source was built by using a quartz tube. The quartz tube was surrounded by a furnace for temperature control. As a carbon feed-stock an ethanol vapor was injected into the argon and hydrogen environment. The plasma environment will be analyzed by optical emission method and the effect of plasma power and the synthesis temperature on the graphene sheets will be analyzed by SEM, AFM and Raman spectra.

The preparation of microporous PVDF membranes with dithiphosphates and modification of surface properties by Helicon plasma

In recent years, Poly(vinylidene fluoride) (PVDF) has received great attention as polymer material for preparing microporous membranes due to its high mechanical strength, chemical resistance, thermal stability, well-controlled porosity and high hydrophobicity. PVDF microporous membranes have been used in wastewater treatment, ultrafiltration and microfiltration for general separation purposes, membrane distillation and rechargeable lithium batteries1. To improve the selectivity of porous membranes, different carriers can be used in preparing. Dithiophosphates were synthesized according to the method described in literature2. No work has been reported to date on microporous PVDF membranes containing dithiophosphates as carrier. In this work, microporous PVDF membranes containing dithiophosphates for Donnan dialysis application were prepared by freeze-gelation method3. To increase the efficiency of the microporous PVDF membranes and to improve their surface properties, they have been treated by Helicon plasma. The plasma treatment is a convenient technique for the chemical and physical modifications of polymer materials for improving the surface properties, such as wettability, adhesion and biocompatibility. To examine the effect of plasma treatment, the surface morphology of the plasma treatment and pristine membranes are characterized by SEM, AFM, FTIR-ATR and contact angle, respectively. In addition, both pristine and plasma treatment membranes were tested for some heavy metals removal by Donnan dialysis.

Graphene synthesis by atmospheric pressure microwave plasma

By injecting ethanol molecules into the argon plasma environment graphene sheets can be produced [1]. From this motivation the atmospheric pressure 2.45 GHz microwave plasma source was built. The argon and helium discharges with ethanol were obtained in a quartz tube which placed in a rectangular cavity. The discharge environment will be analyzed by optical emission method. The synthesized graphene sheets will be analyzed by scanning electron microscopy, x-ray diffraction method and Raman spectroscopy. The plasma power, gas flow rate and temperature effect on graphene sheets will be given.

PTFE and C 3 F 6 deposition on the AISI 1050 stainless steel for lubrication by RF plasma

Summary form only given. In this study, on surface of heat treated AISI 1050 stainless steel was coated in RF vacuum plasma system with different plasma parameters (treatment time, type of gas, power, pressure, electrode distance). First stainless steel surfaces were coated by plasma grafting of sprayed polytetrafluoroethylene (PTFE) using by Argon and Helyum plasma. In the other process, thin layer was deposited by hexafluoropropene (C 3 F 6 ) plasma on the stainless steel surface. After the deposition, surface morphology was analysed by Scaning electron microscope (SEM), Energy-dispersive X-ray spectroscopy (EDS), Atomic force microscope (AFM). Abrasion of samples was tested. As a result of abrasion test the C 3 F 6 plasma processes more effective than PTFE coating. Optical emission spectrum (OES) and current-voltage measurements were used for plasma characterization.