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In this research optical properties of synthesized gold-graphene/polyvinyl alcohol (AuG/PVA) nanocomposite have been investigated. Gold and graphene nano colloidal solution (NCS) synthesized by laser ablation method individually. The resulting NCS were characterized by UV-Vis absorption spectroscopy, scanning electron microscopy (SEM), and transmission electron microscopy (TEM). PVA/Au and PVA/AuG with different concentration of AuG were mixed to form polymeric films via solution casting. Doped polymeric films were analyzed by FTIR and spectrophotometer analyses. The results show that by increasing of AuG concentration, the band gap energy of the PVA films significantly enhanced and other optical parameters such as refraction and extinction coefficients remarkably changed.

Copper (Cu) and nickel (Ni) nanoparticles have been grown simultaneously on glass and silicon substrates by RF sputtering method to form three Cu/Ni nanocomposites at different deposition times. The existence of Cu and Ni peaks in the X-ray diffraction (XRD) profiles confirms the crystalline structure of samples with Cu and Ni atomic content which have also been characterized by Rutherford backscattering (RBS) method. Moreover, the structural and morphological properties of the prepared nanocomposites have been compared with respect to their morphologies by means of atomic force microscopy (AFM) analysis. In order to compare the surface roughness over different spatial frequency ranges and evaluate surface quality, power spectral density (PSD) of each sample has been extracted from AFM data and also, the experimental and theoretical results have been compared. The fractal nature of these nanocomposites has been finally discussed.

This work describes an analysis of titanium dioxide (TiO2 ) thin films prepared on silicon substrates by direct current (DC) planar magnetron sputtering system in O2 /Ar atmosphere in correlation with three-dimensional (3D) surface characterization using atomic force microscopy (AFM). The samples were grown at temperatures 200, 300, and 400°C on silicon substrate using the same deposition time (30 min) and were distributed into four groups: Group I (as-deposited samples), Group II (samples annealed at 200°C), Group III (samples annealed at 300°C), and Group IV (samples annealed at 400°C). AFM images with a size of 0.95 μm × 0.95 μm were recorded with a scanning resolution of 256 × 256 pixels. Stereometric analysis was carried out on the basis of AFM data, and the surface topography was described according to ISO 25178-2:2012 and American Society of Mechanical Engineers (ASME) B46.1-2009 standards. The maximum and minimum root mean square roughnesses were observed in surfaces of Group II (Sq = 7.96 ± 0.1 nm) and Group IV (Sq = 3.87 ± 0.1 nm), respectively.

In this study, Al2O3/Pd(NO3)2/zeolite composite films have been fabricated by roll coating method and characterized by X-ray diffraction, energy-dispersive X-ray spectroscopy and field emission scanning electron microscopy. The gas adsorption was tested in an experimental setup by a continuous gas analyzer KIMO KIGAZ 210 at constant temperature and pressure (32 °C and 1.5 bar) and as a function of reaction time (s). The inlet CO gas concentration was 150 mg L−1, and the saturation level of CO gas concentration was 5 mg L−1. The maximum adsorption capacity (qmax) and maximum adsorption efficiency (%) were calculated as 111.16 mg g−1 and 97%, respectively. Pseudo-first-order, pseudo-second-order, and intra-particle diffusion models were investigated to kinetic study of CO adsorption on Al2O3/Pd(NO3)2/zeolite adsorbents. Results indicated that CO adsorption follows the pseudo-second-order model well according to regression coefficient value (R2 = 0.98), and the value of pseudo-second-order rate constant of adsorption was obtained as 2 × 10−5 g mg−1 s−1. According to the intra-particle diffusion model, adsorption is affected by only one process. So, adsorption of CO by Al2O3/Pd(NO3)2/zeolite adsorbent indicated an effective adsorption by obtained results.

In this study, Cu nanoparticles were synthesized for the first time using an electric field-assisted pulsed laser ablation in liquid media (EPLAL) process and the influence of electric field on the properties of the synthesized nanoparticles was investigated. As-synthesized nanoparticles were successfully characterized using X-ray diffraction (XRD), field emission scanning electron microscopy (SEM), transmission electron microscopy (TEM), electron dispersive X-ray analysis (EDX), fourier transform-infrared (FT-IR), Raman spectra, Dynamic light scattering analysis (DLS) and ultraviolet–visible (UV–Vis) spectroscopy. The XRD analysis demonstrated face centered cubic (FCC) structure of pure Cu nanoparticles. The FE-SEM and TEM analyses revealed that increasing the strength of electric field leads to fabricating nanoparticles with narrower range of size distribution. Also, the copper nanoparticles formation were confirmed by the characteristic surface plasmon resonance (SPR) peak in UV–Vis spectra. On the other hand, the UV–Vis spectra displayed the blue-shifts from 588 to 582 nm of SPR peak by increasing the strength of applied electric field, which indicated the size of Cu nanoparticles were reduced. Furthermore, the DLS analysis confirmed that the size of Cu nanoparticles reduced from 115.8 to 91.7 nm by increasing the strength of applied electric field.

The vortex gas injection into plasma torch is considered as a method for reducing electrodes erosion. In order to investigate the effects of vortex gas injection on plasma structure, as well as the effect of gas viscosity on the rate of rotation, a three-dimensional nonequilibrium and time-dependent non-transferred DC plasma torch model has been simulated. Viewing the general characteristics of the plasma shows that the model works well. The results have shown that if the components of the inlet gas velocity are not properly selected, it is possible that the rotary effects of the gas are greatly depleted even before the gas reaches the cathode tip and plasma formation. In this case, only the change in the axial component of the gas causes changes in the structure of the plasma. Vortex reduction is also observed during the movement of cold gases. It is observed that the change in viscosity of gas has significant effects on the rate of the vortex.

Significant applications of metallic nanocatalysts motivated us to study the role of catalyst contents by choosing Cu–Ni nanocatalyst in synthesizing carbon nanotubes (CNTs). Cu–Ni thin films were prepared by RF sputtering method with different deposition time of Ni. They inserted the prepared catalysts into a quartz tube reactor for carbon nanotubes fabrication. Scanning electron microscopy (SEM) recorded the diameter distribution of multi walled carbon nanotubes (MWCNTs) while atomic force microscopy (AFM) was applied for surface roughness estimation. Both analyses confirm the positive effect of deposition time on the catalytic properties of Cu/Ni nanocatalysts which ends to the improved quality of prepared CNTs. In addition, the structure of multi walled carbon nanotubes were investigated by Raman spectroscopy.

Production and characterization of gold/silicon nanocomposites have been investigated experimentally, using laser ablation method. Firstly Si nanoparticles and Au nanoparticles were synthesized by ablation of their bulk in deionized water with the fundamental wavelength of Nd:YAG pulsed laser separately. Then the produced Au nanoparticles and Si nanoparticles suspensions were mixed and irradiated with the second harmonic of the pulsed Nd:YAG laser operating at 532 nm. Effects of the volumetric ratio of Au and Si nanoparticle suspensions in the characteristics of Au/Si nanocomposite have been studied in this research. A variety of analytical techniques such as UV–Vis-NIR spectroscopy, X-ray diffraction, DLS measurement, FTIR spectrum, photoluminescence spectroscopy, and TEM and SEM imaging were applied to characterize the products. Strong plasmonic absorption band of Au nanoparticles around 530 nm made them to be heated and melted by the green laser irradiation to form nanocomposite with Si nanoparticles nearby.

Effects of DC magnetic field in the range of 0–180 mT on the properties of cobalt oxide nanoparticles (Co3O4 NPs) synthesized by pulse laser ablation method in distilled water has been investigated. Ablation was carried out in the presence of permanent magnets with variable strengths. Significant blue shift in excitonic absorption peaks of produced nanoparticles show that with increasing the magnetic field strength during the ablation process, size of nanoparticles was decreased noticeably. This result was confirmed by SEM and TEM images. XRD pattern show that with applying external magnetic field we may have crystalline structure nanoparticles while in the absence of external magnetic field, only amorphous phase of Co nanoparticles was produced. FTIR spectra present the metal oxygen vibration at 614 and 668 cm−1, revealed octahedral and tetrahedral site of cobalt oxide system. In overall it can be concluded that external magnetic field is a strong tool to control the properties of laser ablation produced ferromagnetic nanoparticles.

Summary Till now electron microscopy techniques have not been used to evaluate the plasma–target interactions undergone during the magnetron sputtering process. The destructive nature of this interaction severely alters the target microstructure. Utilising quantitative microscopy techniques can shed light on the complex plasma and solid‐state processes involved which can ultimately lead to improved functional thin film deposition. As a representative functional material, aluminium‐doped‐zinc oxide (AZO) is an upcoming alternative to conventional transparent electrode wherein the process optimisation is of great importance. In this paper, we evaluate the pre‐ and post‐sputter field emission scanning electron microscopy (FESEM) data for ceramic AZO target fabricated at three final sintering temperatures (1100°C, 1200°C and 1300°C). In all cases, grain boundaries are merged in addition to a visible reduction in the secondary phases which makes segmentation‐based image analysis challenging. Through surface statistics (i.e. fractal dimension, autocorrelation length, texture aspect ratio and entropy) as a function of magnification we can quantify the electron microscopy image of the microstructure. We show that the plasma–microstructure interaction leads to an increase in autocorrelation length, texture aspect ratio and entropy for the optimum AZO ceramic sputtering target sintered at 1200°C. Furthermore, a maximum reduction in fractal dimension span (as determined by exponential regression) is also observed for 1200°C. In addition to the evaluation of plasma effects on sintering, our approach can provide a window towards understanding the underlying thin film growth mechanisms. We believe that this technique can be applied to the defect characterisation of a wide range of polycrystalline ceramic sputtering targets (e.g. ITO, CZTS, GAZO and so on) with the ultimate goal of improving the magnetron sputtering process and the resulting functional thin film. Lay Description Magnetron sputtering allows scientists to make functional thin films on the order of the nanoscale. In this technique, atoms are plucked from a ‘target’ then placed onto a substrate forming a thin nanometric film: all thanks to magnets, a special power supply and the fourth state of matter (plasma). Understanding what is going on and how to make a ‘good’ thin film is important for making better light emitting diodes, solar cells and light sensors. Scientists use electron microscopy to see what is going on in the microstructure of the sputtered thin films to fine tune the sputtering recipe. Here, for the first time, we have applied electron microscopy to see the surface of the microstructure before and after magnetron sputtering. This will help us understanding the plasma–microstructure interaction allowing us to make more informed decisions when fine‐tuning the sputtering process to get improved thin films. This is a case study of aluminium‐doped zinc oxide (AZO) target that could potentially replace indium tin oxide (ITO), which is widely used as a transparent electrode in devices involving light and electricity. In this case, improved characteristics would be lower electrical resistivity and higher transmission of light. We show that it is possible to use a mathematical description (e.g. the fractal dimension) of the scanning electron microscopy picture to show a link between the target surface and the functional properties. Simple explanation of fractal dimensions by Sixty Symbols ○ https://www.youtube.com/watch?v=cmBljeC79Ls Experimental demonstration of magnetron sputtering by The Thought Emporium ○ https://www.youtube.com/watch?v=Cyu7etM-0Ko Introductory video on magnetron sputtering by Applied Science ○ https://www.youtube.com/watch?v=9OEz_e9C4KM Demonstration of AZO target fabrication and sputtering by Pradhyut Rajjkumar ○ https://www.youtube.com/watch?v=kTLaTJfNX3c Simple explanation of a DIY SEM by Applied Science ○ https://www.youtube.com/watch?v=VdjYVF4a6iU

Tungsten sub-oxide (W17O47) nanoparticles were produced for the first time, via pulsed laser ablation of a pure tungsten target in distilled water. The beam of a Q-switched Nd:YAG laser of 1064 nm wavelength with 0.6, 0.8, 1.2 and 1.4 J/cm2 fluences was employed to irradiate the target. Produced nanoparticles were characterized using field emission scanning electron microscopy coupled with energy dispersive spectrometry, transmission electron microscopy, Fourier transform infrared spectroscopy, X-ray diffraction (XRD), UV–Vis absorption spectroscopy and room temperature Photoluminescence (PL). XRD patterns revealed that all samples possess the monoclinic structure corresponding to $${\mathrm{W}}_{17}{\mathrm{O}}_{47}$$ phase. With increasing the laser fluence, the average size of the nanoparticles increased and subsequently, their band gap energy decreased. The PL spectra of the samples show the presence of oxygen vacancies or defects.

In this work, the effects of liquid environments on the characteristics and optical properties of carbon nanostructures – in particular, Graphene Oxide (GO) – prepared by pulsed laser ablation were studied experimentally. The second harmonic beam of a Q-switched Nd:YAG laser of 532 nm wavelength at 6 ns pulse width and 0.7 J/cm2 fluence was employed to irradiate the graphite target in liquid nitrogen, deionized water, and 0.01 M CTAB solution under the same initial experimental conditions. Produced nanostructures were characterized by Raman scattering spectrum, FE-SEM and TEM images, Photoluminescence, and UV–Vis-NIR spectrum. TEM and FE-SEM images show sheet-like morphology with few square micrometer area graphenes in all samples. Raman and UV–Vis-NIR analyses show that graphene is oxidized due to the presence of oxygen molecules in ablation environment. Results demonstrate that the graphene nanosheets produced in deionized water are multilayer, contains the largest sp2 domain size, the least defects and the lowest possibility of aggregation.

To study the alumina template pore size distribution as a function of Al thin film grain size distribution, porous alumina templates were prepared by anodizing sputtered aluminum thin films. To control the grain size the aluminum samples were sputtered with the rate of 0.5, 1 and 2 Å/s and the substrate temperature was either 25, 75 or 125 °C. All samples were anodized for 120 s in 1 M sulfuric acid solution kept at 1 °C while a 15 V potential was being applied. The standard deviation value for samples deposited at room temperature but with different rates is roughly 2 nm in both thin film and porous template form but it rises to approximately 4 nm with substrate temperature. Samples with the average grain size of 13, 14, 18.5 and 21 nm respectively produce alumina templates with an average pore size of 8.5, 10, 15 and 16 nm in that order which shows the average grain size limits the average pore diameter in the resulting template. Lateral correlation length and grain boundary effect are other factors that affect the pore formation process and pore size distribution by limiting the initial current density. Keywords: Porous alumina, Alumina template design, Sputtering, Grain size distribution

In this study, electrical arc discharge method is used for the synthesis of multi wall carbon nanotubes (CNTs). The advantages of applied setup for producing CNTs are simplicity, low-cost procedures and avoiding the multistep purification. The experiments were optimized by submerging graphite electrodes inside deionized water and various concentrations of sodium chloride solution. The purpose of this research is to investigate the effect of liquid medium on growth, size and quality of the CNTs structures. The results show that CNTs of 150 Â µm length or larger with high purity and quality without using catalyst are produced on the cathode surface. Furthermore, the quantity of CNTs is influenced by NaCl concentration. Scanning electron microscopy, Raman spectroscopy and X-ray diffraction technique were used to characterize the results.

In this study, the effect of oxygen content on a thin copper oxide layer deposited on BK7 and steel substrates by DC magnetron sputtering were investigated. Argon as working gas with impurity of 99.9% and various oxygen ratios were used to sputter a pure Cu cathode target in a cylindrical geometry. The produced samples were analyzed by X-ray diffraction (XRD), energy-dispersive X-ray (EDX), atomic force microscopy (AFM), and spectrophotometry techniques. The films thickness was measured by profilometer facility. The results show that by increasing oxygen content in the working gas the sputtering rate reduces. Moreover, the type of oxide phase (Cu2O or CuO) in the synthesized layer and consequently its optical properties dramatically depend on Ar/O2 ratio in the working gas.

Three steps anodization process is used to synthesize highly ordered and uniform multilayered titanium oxide (TiO2) nanotubes and effect of different anodization voltages are studied on their physical properties such as structural, morphological and optical. The crystalized structure of the synthesized tubes is investigated by X-ray diffractometer analysis. To study the morphology of the tubes, field emission scanning electron microscopy is used, which showed that the wall thicknesses and the diameters of the tubes are affected by the different anodization voltages. Moreover, optical studies performed by diffuse reflection spectra suggested that band gap of the TiO2 nanotubes are also changed by applying different anodization voltages. In this study using physical investigations, an optimum anodization voltage is obtained to synthesize the uniform crystalized TiO2 nanotubes with suitable diameter, wall thickness and optical properties.

Application of ion beam has been widely used as a surface modification method to improve surface properties. This paper investigates the effect of argon ion implantation on surface structure as well as resistance against tantalum corrosion. In this experiment, argon ions with energy of 30 keV and in doses of 1 × 1017–10 × 1017 ions/cm2 were used. The surface bombardment with inert gases mainly produces modified topography and morphology of the surface. Atomic Force Microscopy was also used to patterned the roughness variations prior to and after the implantation phase. Additionally, the corrosion investigation apparatus wear was applied to compare resistance against tantalum corrosion both before and after ion implantation. The results show that argon ion implantation has a substantial impact on increasing resistance against tantalum corrosion. After the corrosion test, scanning electron microscopy (SEM) analyzed the samples’ surface morphologies. In addition, the elemental composition is characterized by energy-dispersive X-ray (EDX) analysis. The purpose of this paper was to obtain the perfect condition for the formation of tantalum corrosion resistance. In order to evaluate the effect of the ion implantation on the corrosion behavior, potentiodynamic tests were performed. The results show that the corrosion resistance of the samples strongly depends on the implantation doses.

In this experimental study, Cd (OH)2/CdO nanostructures were produced by pulsed laser ablation method. The beam of a Q-switched Nd:YAG laser with wavelength of 1064 nm at different fluences was employed to irradiate the cadmium target in distilled water. The obtained products at different fluences of laser pulse were characterized by UV–Vis-NIR spectroscopy, X-ray diffraction, scanning electron microscopy, and transmission electron microscopy. Results show that both morphology and chemical bonds of produced Cd nanostructures were changed by increasing the laser fluence. The absorption spectra shows that the Cd(OH)2 nanostructures could be transformed into CdO nanostructures with increasing the laser fluence. XRD analysis showed the presence of crystalline γ-Cd(OH)2, Cd(OH)2 and CdO phases, in the monoclinic, hexagonal and cubic structure, respectively. Results revealed that obtained nanostructures are particle in lowest fluence, while wire shaped nanostructures were formed with increasing the laser fluence. An increase of the laser fluence induced the synthesis of higher aspect ratio nanowires with a smaller tendency of adhesion.

The role of laser fluence in producing cobalt oxide nanoparticles in distilled water by laser ablation method has been studied experimentally. Output of a pulsed Nd:YAG laser of 1064 nm wavelength and 7 ns pulse width with 10 Hz repetition rate was employed to irradiate a high purity cobalt bulk in distilled water. According to results, size of produced nanostructures as well as their oxidation was strongly under the influence of laser energy. Although a high purity Co bulk was used as the target of laser irradiation in the experiment but produced nanoparticles were mainly cobalt oxides. X ray diffraction pattern indicates that produced nanostructures are Co3O4. The excitonic absorption peak of Co3O4 nanoparticles was occurred in UV region. Results show that with increasing the fluence of laser pulse, size of nanoparticles was decreased while their aggregation was increased noticeably.

In this study, the effect of a nitrogen compression plasma flow on the microstructural and mechanical properties, as well as on the elemental and phase compositions of a Zr/chromium–nickel steel system has been investigated. The Zr/steel system was exposed to a single pulse of the compression plasma flow or to a series of pulses. The samples were characterized by scanning electron microscopy, Auger electron spectroscopy, X-ray diffraction, and energy dispersive X-ray analyses, and subjected to a Vickers microhardness test. The findings showed the formation of a surface modified layer alloyed by Zr with the thickness of up to ∼12 μm. The modified layer contains α- and γ-iron-based solid solutions, the Fe 23 Zr 6 intermetallic compound, and ZrN and Cr 2 N nitrides due to nitrogen diffusion. The microhardness of the modified layer increased by a factor of ∼2.

The new candidates for laser fusion energy with minimized radioactivity were presented. The possibility of side-on laser ignition of H–11B with negligible radioactivity encouraged to study the fusion of solid state H–7Li fuel which again turns out to be only about ten times more difficult than the side-on ignition of solid deuterium–tritium using petawatt-picosecond laser pulses at anomalous interaction conditions if very high contrast ratio. Updated cross sections of the nuclear reaction are included. In other words, the specific approach discussed here involves inducing a fusion burn wave without radioactivity by laser-driven impact of a relatively large block of plasma on the outside of a solid density H–11B and H–7Li targets.

In this paper the effects of substrate temperature (room temperature – 350 °C) on the phase composition and crystallization orientation of the tantalum thin film deposited by direct current magnetron sputtering in an extremely low power deposition regime are presented. In this experiment, heating the substrates to 350 °C resulted in the growth of the hard and brittle tetragonal crystalline structure (β-Ta). Deposited tantalum has a conical structure with large voided boundaries. Sheet resistance of samples is much larger than for the convenient conductors which decreased with increasing the substrate temperature.

This paper is the results of oxygen ion implantation on morphological and electrical properties of indium phosphate (InP) semiconductor wafers. The oxygen ions were implanted at 30 keV and various doses in the range between 5×10 15 to 5×10 17 ions/cm2 and at nearly room temperature. The changes in surface roughness and resistivity before and after the implantation is studied using atomic force microscopy (AFM) and four-point probes technique, respectively. The results show that the resistivity is depend on the ion implantation dose. In addition, the RMS roughness of implanted samples dramatically increases by accumulation of oxygen ion dose.

An anomalously strong increase of nuclear fusion gains for laser driven compression and thermal ignition of hydrogen-boron11 has been discovered from computations by using the latest results of Newins and Swain about details of a resonance maximum of the astrophysical S-function at 148 keV for the reaction cross-sections. Extensive computations based on volume ignition showed some usual improvements of the fusion gains. However, for a very narrow range of parameters, the increase of the gain was found to be higher by more than a factor 6. This is very unusual in all similar computations and is related to retrograde properties which were known for other parameter values. On top it is most important that the anomalous range is in the practically very interesting range for incorporation of laser pulse energies of few megajoules. The gains of up to 20 may be of interest for power generation in future by the high density fusion scheme.

The TiN thin films were deposited on p-type silicon (100) substrates using reactive planar DC magnetron sputtering system. The target was 99.99% pure Ti. The reactive sputter gas was a mixture of Ar (99.999%) and N2 (99.999%) with the ratio Ar (97%) and N2 (3%) by volume. Structural characterization of the coating was done using X-ray diffraction (XRD). The surface roughness of the coating was determined using an Atomic Force Microscope (AFM). The reflectivity of thin films was investigated by a spectrophotometer system. The X-ray diffraction measurements showed that by increasing the substrate temperature during the growth, change in crystalline structure will occur. The crystallite size of the films determined by Scherrer’s equation, and the crystallite size measured by AFM also increased by increasing the substrate growth temperature. The surface reflectivity measurements indicate that by increasing the substrate growth temperature, the optical properties of the films changes. The change in optical properties and crystalline structure of the films indicate that substrate growth temperature plays an important role in structure and morphology of the grown layers.

In this paper, aluminium samples with 99.96% purity were exposed to ion beam, extracted from CH4 plasma. Implantation of ions were performed for 50 keV energy and various doses ranging from 1 × 1017 to 6 × 1017 ions/cm2. Morphology of surfaces, roughness and its evolution during variation of ion dose has been studied by atomic force microscopy (AFM). Microstructure of the modified surfaces after ion implantation has been obtained by X-ray diffraction technique and Raman spectroscopy. Formation of aluminium carbide (Al4C3) was confirmed by XRD results at implantation doses of 3 × 1017 and 6 × 1017 ions/cm2. In addition, it was observed that when the ion dose is increased, orientation of aluminium planes change from (2 2 0) to (2 0 0). Corrosion test was performed and compared for implanted and un-implanted samples. The results showed that corrosion resistivity increase by accumulation of ion dose.

In this study, copper samples with 99% purity implanted by N+ and N2 + ions. Implantation of ions performed at 50 keV and various doses ranging from 1 × 1017 to 1 × 1018 ions/cm2. Morphology of samples’ surface studied by atomic force microscopy. Microstructure of modified surfaces after ion implantation obtained using grazing incidence X-ray diffraction technique (GIXRD). Formation of both copper nitride and copper trinities confirmed by GIXRD results. Microhardness properties and corrosion behavior of implanted samples measured by Vickers and corrosion test, respectively. The maximum hardness of copper surface observed after nitrogen ion implantation at the dose of 3 × 1017 ions/cm2. Moreover, the results showed that corrosion resistivity significantly increase.

Pseudomonas aeruginosa is one of the most important pathogens commonly seen in immuno-compromised patients. A low cost corona discharge system that works at atmospheric pressure and operates with AC high voltage power supply has been applied to Pseudomonas and Escherichia coli (E-Coli) bacteria plates. The tests were aimed to determine the sterilization efficiency of corona discharges. Optimal killing parameters such as time, applying magnetic field and added hydrogen peroxide were tested for bacteria samples. The results obtained were encouraging and 100% decontamination was observed within the first 15 min of corona exposure. The decontamination efficiency was however raised significantly both through introduction of hydrogen peroxide during corona treatment and applying a magnetic field.

In this paper the effect of nitrogen ion implantation at the energy of 50 keV and doses in the range between 1017 and 2 × 1018 ions/cm2 on silver surface has been discussed. X-ray diffraction (XRD) analysis was used to characterize microstructure of implanted layer. The XRD results confirmed that by such implantation AgN3 has been produced. Silver trinitride with orthorhombic structure was formed on cubic structure of silver surface. RMS roughness of implanted samples have been obtained using atomic force microscopy (AFM) analysis and compared with un-implanted sample. Microhardness properties of implanted samples measured by Vickers test. The results show that by increasing the ion dose up to 1 × 1018 ions/cm2 hardness enhances. Finally, reflection changes at the UV–Vis-NIR region measured by diffuse reflectance accessory of a spectrophotometer. The results of spectrophotometry analysis show reduction in diffused reflection spectrum of nitrogen implanted samples.

In this paper the influence of DC glow discharge HMDSO-N2 plasma on wettability and surface properties of Biaxial-oriented polypropylene (BOPP) polymeric surfaces, has been investigated. The effects of plasma exposure time and HMDSO percent on the surface energy and wettability of the BOPP films were characterized using Fourier transform infrared spectroscopy (FTIR), Atomic force microscopy (AFM) and contact angle measurement. A clear change in the surface energy of BOPP films due to plasma treatment was observed. In this work we report changing surface properties of BOPP films instead of plasma treatment time and HMDSO ratios.

In this paper the effect of plasma treatment by using mixed gas (N2/O2) on surface properties of a Polypropylene PP films were investigated as a function of O2 content and treatment time. Results obtained by using Fourier Transform infrared spectrometer (FTIR), contact angle measurement and scanning electron microscopy (SEM). It is found that plasma treatment can change chemical structure of polymer surfaces partially. SEM images revealed distinct changes in topography of PP due to O2/N2 plasma treatment. Finally wettability and surface energy before and after treatment investigated in different conditions.

Ion implantation has been widely used as a surface modification technique to improve surface properties. In this work, argon ions of 30 keV energy have been implanted into AISI 304 stainless steel at different fluences ranging from 3 × 1017 to 1 × 1018 Ar+/cm2. The surface bombardment with inert gases mainly produces structural changes and modify topography and morphology of the surface. The AFM analysis of implanted samples clearly shows significant change in surface. In order to evaluate the effect of the ion bombardment on the corrosion behavior, potentiodynamic tests were performed. The results show that the corrosion resistance of the samples strongly depends on the implantation fluences.

In this work a DC plasma reactor was used for deposition of plasma polymerized coating from hexamethyldisiloxane–Ar (35/65%) mixture on polypropylene films. Surface energy parameter have been calculated using Owens–Wendt approaches with the sessile drop method are used to obtain the dispersive γD and polar γP component of surface free energy. The surface morphology of samples were investigated using scanning electron microscope. Also the chemical properties and wetability of prepared samples were tested using Fourier transform infrared spectroscopy and contact angle measurement, respectively.

Carbon dioxide ions with 29 keV energy were implanted into (4 0 0) high-purity p-type silicon wafers at nearly room temperature and doses in the range between 1 × 10 16 and 3 × 10 18 ions/cm 2 . X-ray diffraction analysis (XRD) was used to characterize the formation of SiC in implanted Si substrate. The formation of SiC and its crystalline structure obtained from above mentioned technique. Topographical changes induced on silicon surface, grains and evaluation of them at different doses observed by atomic force microscopy (AFM). Infrared reflectance (IR) and Raman scattering measurements were used to reconfirm the formation of SiC in implanted Si substrate. The electrical properties of implanted samples measured by four point probe technique. The results show that implantation of carbon dioxide ions directly leads to formation of 15R-SiC. By increasing the implantation dose a significant changes were also observed on roughness and sheet resistivity properties.

In this work the surface of (4 0 0) p -type Si wafers is bombarded with 29 keV nitrogen ions at various ion beam fluency varied from 10 16 to 10 18 ions/cm 2 and the results are investigated. Si 3 N 4 film with orthorhombic structure is formed on silicon surface with cubic structure while the lattice parameter of the generated layer is not affected by change of nitrogen ion beam dose. RMS roughness of implanted samples increases by increasing the nitrogen dose, specially when the dose is more than 3×10 17 ions/cm 2 . Surface resistivity of samples is increased by increasing the dose of ion beam. Although changes in the transmission of implanted samples does not differ very much in comparison with row sample but reflection of implanted samples decrease about 60% for the electromagnetic wave in the range of 200 to 1500 nm. Absorption coefficient of samples is obtained and the band gap energy of samples is calculated. It is observed that formation of defect levels changes the magnitude of band gap energy.

This work presents the results of a low-energy nitrogen ion implantation of AISI 304 type stainless steel (SS) at a moderate temperature of about 500°C. The nitrogen ions are extracted from a Kauffman-type ion source at an energy of 30 keV, and ion current density of 100 μA cm−2. Nitrogen ion concentration of 6 × 1017, 8 × 1017 and 1018 ions cm−2, were selected for our study. The X-ray diffraction results show the formation of CrN polycrystalline phase after nitrogen bombardment and a change of crystallinity due to the change in nitrogen ion concentration. The secondary ion mass spectrometry (SIMS) results show the formation of CrN phases too. Corrosion test has shown that corrosion resistance is enhanced by increasing nitrogen ion concentration.

In this paper the characteristics of Tantalum nanoparticles produced by laser ablation method is investigated experimentally with a first harmonic of a Q-switched Nd:YAG laser of 1064 nm wavelengths at 6 ns pulse. Spherical nanoparticles of Ta and tantalum oxide have been produced successfully by using a Ta target in ethanol. The fluency of laser was 0.9 J/cm 2 . The samples were characterized by using transmission electron microscopy (TEM), photo luminescence (PL), X-ray diffraction (XRD) and absorption spectroscopy analyses. The size of produced nanoparticles is mainly in the range between 10–20 nm, structural and phase compositional of produced Ta nanoparticles.

The chromium thin films were prepared using ion beam deposition on stainless steel 304. The chromium films were implanted by nitrogen ions after deposition at doses in the range of 4.5 × 1017 to 2.7 × 1018 N+/cm2 and energy of 30 keV. The formation of nitride phases and corrosion behavior after nitrogen implantation were characterized by XRD and corrosion test, respectively. The results show that corrosion resistance rise, reach to a maximum at dose of 1.8 × 1018, and then fall down at higher doses. In addition, the effect of corrosion tests was analyzed using scanning electron microscopy (SEM).

The measurement of very narrow high density plasma blocks of high ion energy from targets irradiated with ps-TW laser pulses based on a new skin depth interaction process is an ideal tool for application of ion implantation in materials, especially of silicon, GaAs, or conducting polymers, for micro-electronics as well as for low cost solar cells. A further application is for ion sources in accelerators with most specifications of many orders of magnitudes advances against classical ion sources. We report on near band gap generation of defects by implantation of ions as measured by optical absorption spectra. A further connection is given for studying the particle beam transforming of n-type semiconductors into p-type and vice versa as known from sub-threshold particle beams. The advantage consists in the use of avoiding aggressive or rare chemical materials when using the beam techniques for industrial applications.

This paper is the results of oxygen ion implantation on morphological and electrical properties of indium phosphate (InP) semiconductor wafers. The oxygen ions were implanted at 30 keV and various doses in the range between 5 × 1015 and 5 × 1017 ions/cm2 and at nearly room temperature. The changes in surface roughness and resistivity before and after the implantation is studied using atomic force microscopy (AFM) and four-point probes technique, respectively. The results show that the resistivity is depend on the ion implantation dose. In addition, the RMS roughness of implanted samples dramatically increases by accumulation of oxygen ion dose.

A pre-deposited tantalum thin film on a Si(100) substrate was treated by compression pulsed plasma flow. SEM images demonstrated the formation of spherical clusters with multi-level structures. Formation of crystalline metal rich tantalum silicides is confirmed by X-ray diffraction and EDX elemental map analysis. The results show great potential application of compression plasma flow for the development of novel nanostructured metal-silicide materials.

For production of transistor electronics for lengths below the optical to ultraviolet wavelengths, technologies with plasmas and electron‐ ion‐ and neutral beams are studies where a combination with laser driven ion beam sources is involved. The same can be used for production of p‐n junctions in silicon, gallium arsenide or conducting polymers diodes and solar cells.

Ion implantation has been used to modify the mechanical properties of a wide range of metals and alloys using plasma techniques for ion sources and plasma surface treatment [1]. In this study AISI 52100 steel disks, containing 1.5 wt% Cr as the major alloying element, were implanted with nitrogen and carbon dioxide ions at the energy of 90 KeV, with dose in the range 1 × 1018 to 1 × 1019 N2+ ions cm−2, and 3 × 1018 to 1 × 1019 for co2+ ions cm−2. Ion beam current densities and sample temperature, during implantation were 3–6 μA/cm2 and 170°C, respectively. Experiments show, hardness of sample, increases 30–49% using N2+ ions, and 5–17% using co2+ ions. In order to explain the results, formation of beta‐CrN and carbide pahses have been carried out using X‐ray diffraction technique.

The interaction of a dense compressed nitrogen plasma flow with a system of Ta-Ti layers on a silicon substrate has been investigated. This plasma flow was generated in a quasi-stationary pulsed plasma accelerator that can provide a supersonic high energy plasma flux. The plasma pulse duration, discharge current, concentration, and energy densities absorbed by the target were 100 µs, 80 kA, 1018 cm−3, and 3–13 J/cm2 respectively. The samples were exposed to a single plasma pulseor to a series of pulses and were characterized by scanning electron microscopy, X-ray diffraction, and energy dispersive X-ray analyses. The result showed that the changes in the elemental and structure phase compositions depends on energy and number of plasma pulses. Formation of Ti5Si3 and Ta2N, are the main results of the current research.