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We introduce a study of image analysis of kefir biofilms associated with Acai extract prepared by fermentation of fresh kefir grains natural. Atomic force microscopy data were studied, aiming to understand how the concentration of acai berry (Euterpe oleracea Mart.) influences the surface morphology as well as the texture complexity, evaluated by the fractal dimension. The results showed that the superficial morphology was affected by the increase of Acai concentration in the biofilms, as well as the fractal dimension. It has also been observed that the surface of the biofilm presented saturation when concentration changes from 40 to 60 ml. On the other hand, it was observed that the intermediate sample produced with 20 ml of acai berry seems to be the best point for biofilms production that can serve as a skin dressing since other studies related to mechanical properties and in vitro and in vivo tests can confirm this applicability. Thus, the characterization of the surface morphology of kefir biofilms by the evaluation of surface statistical parameters and fractal geometry may provide promising results regarding the applicability of these films. RESEARCH HIGHLIGHTS: We characterized the structural complexity of the 3-D surface of the kefir biofilms associated with açaí extract. The 3-D surface analysis of the samples was performed using an atomic force microscope operating in contact mode. We determined the stereometric and fractal dimension of the analyzed samples.

The article presents results on fabrication and characterization of transparent, oxide-based junction diodes on quartz substrates. The devices are made by radio frequency magnetron sputtering in the form of sandwich structures: ITO:n-ZnO:p-NiO (homojunction) and ITO:n-ZnO:p-NZO (heterojunction). The microstructure, crystalline structure, and micromorphology features of deposited samples are studied by means of X-ray diffraction, Atomic Force Microscopy, and Scanning Electron Microscopy. Obtained results are used to derive statistical, fractal and functional surface characteristics that exhibited secondary alignment patterns. Apart from that, optical and electrical measurements are carried out as well. Optical transmittance peaked at 80% in visible range, but substantially increased after annealing. Due to structural differences, heterojunction was found to follow linear current-voltage dependence specific of ohmic contacts, whereas homojunction was found to follow non-linear characteristics as in junction diode.

A new water-tolerant nickel-based coordination polymer (Ni-PDC) was prepared by facile precipitation method employing 1,3-propanedicarboxylic acid (PDC) and nickel acetate. The prepared coordination polymer was utilized in the adsorptive removal of anionic (Congo red and methyl orange) and cationic dyes (methylene blue and rhodamine B) from aqueous solutions. The obtained data demonstrated that Ni-PDC is an efficient adsorbent for removing anionic dyes from aqueous solution with high efficiency and fast kinetic. The prepared Ni-PDC was found to be very effective for removing anionic dyes as Congo red eliminated from the aqueous solution more than 96% during the first 2 mins. Moreover, the pH has not remarkable effect on the removal efficiency of Congo red by Ni-PDC and thus neutral pH is the best medium for its adsorption. The Ni-PDC can be recovered after desorbing organic dyes, and the removal efficiency was found to be nearly unchanged after four cycles.

In this work, the stereometric 3-D surface topography as well as the optical properties of the Al doped ZnO (AZO), and Al/Cu co-doped ZnO (CAZO) thin films were investigated. These films were deposited with different thicknesses of 50 and 150 nm. The effect of dopants (Al, Cu) and sputtering parameters on the microstructures, crystalline structures, and fractal features were probed by Atomic Force Microscopy (AFM), X-ray diffraction, and Rutherford back scattering. AFM analysis of 3-D surface texture provided a deeper insight into their characteristics and implementation in graphical models and computer simulation. Studying surface roughness of samples at nanometer scale revealed a fractal structure which confirmed the relationship between the value of the fractal dimension and surface roughness parameters. Moreover, the optical properties of AZO and CAZO thin films and the relationship between their optical band gaps and their varied thicknesses were evaluated by Ultraviolet–visible spectrophotometry.

Due to the industrial applications of nasno materials, the growth of Copper oxide (CuO) nanowires (NWs) at the same and opposite directions of the electric and gravitational fields was investigated to study the effects of fields on the NWs properties. The experiments were designed to grow NWs using thermal oxidation method at 450 °C for 50 h. NWs growth was evaluated to study two distinct cases; first, substrates exposed to the gravitational field and second those treated with electric field (EF) in-lined with gravitation field (GF). It was observed that the electric field developed a diameter homogeneity while compressing the NWs and decreasing the diameters. Furthermore, the GF influenced only the length of the NWs, while the EF had an impact on both length and diameter of the NWs. The direction of fields played an important role in NWs morphology and intensity of XRD pattern and optical properties. It was also observed that field direction greatly influenced the NWs length and diameter.

To overcome recent energy and environment challenges, developing efficient and low cost photocatalysts are unavoidable. In this context, design of semiconductor nanostructures modified with earth abundant co-catalysts for water splitting reactions requires well engineered and controlled process to optimize surface interface and maximize nanocomposite system efficiency. Here, TiO 2 nanotube were synthesized electrochemically and decorated with cobalt based nanostructure co-catalyst for water oxidation reaction using low cost and scalable electro-deposition approach. By changing deposition parameters and complete studying on samples surface morphology and related statistical analysis data, correlation between all morphological parameters and photoelectrochamical activity of correspondence photoanode was illustrated for the first time. Based on SEM analysis and surface analysis data as well as catalytic performance investigation, nanotubes decorated with Co nanoparticles at 0.1 mA cm −2 deposited for 2000 s presented the best performance with most isotropic surface. Results suggested that by tuning deposition parameters surface structural parameters like fractal dimension, corner frequency, roughness and feature shape and size can be engineered completely. Moreover, X-ray diffraction data along with Rietveld method revealed coexistence of anatase, rutile and Ti 2 O 3 phases in the photoanode while poor crystallinity of grown cobalt based nanostructures was confirmed.

The aim of the present study is to verify how alternations of annealing temperatures modify optical and micromorphological properties of n-ZnO/p-NZO and n-ZnO/p-NiO multilayers. As can be seen, the optical analysis of homojunctions and hetrojunction thin films shows a red shift by increasing annealing temperature which means that annealing can shift absorption edge coefficient to the lower values of energies. Also, the effective parameters on optical properties of homo- and hetrojunction thin films such as optical band gap, Urbach energy, steepness parameter, and skin depth have been studied by their transmittance spectra. Moreover, the micromorphology of n/p ZnO homo- and heterojunctions transparent diodes have been studied by atomic force microscopy in combination with modern image processing techniques. The nano scaled stereometric analysis provides significant insights into the influence of preparation process on surface texture geometry. According to the results extracted from AFM micrographs by MountainsMap® software, it is observed that Q/ITO/ZnO/NZO sample with 300 °C annealing temperature has the normal distribution of peaks with the highest percentage of isotropy. In addition, it is observed that Q/ITO/ZnO/NiO with 500 °C annealing temperature has the most regular topography.

Un-doped and Cu-doped ZnO (CZO) thin films were prepared by radio-frequency (RF) sputtering. The effects of Cu doping and annealing treatments on the microstructure, fractal features and photoluminescence of these thin films were investigated by different characterization techniques including X-ray diffraction, X-ray photoelectron spectroscopy (XPS), atomic force microscope (AFM), photoluminescence (PL) and Rutherford back scattering. The results indicated that the Cu-doping enhanced the c-axis preferential growth of the ZnO films, however introduced crystal defects and micro tensions in the crystal lattice reducing the crystal size and the lattice parameter c. The XPS studies revealed that the states of Cu in the doped films were Cu 1+ and Cu 2+ , and the PL characterizations showed that the incorporation of Cu in the crystalline structure of the ZnO thin films produced a green emission at 530 nm. The annealing treatments increased the crystal size in the [001] direction and reduced the lattice parameter c due to the accommodation of the Cu atoms in equilibrium positions. Also, these treatments increased the intensity of the PL peaks. All samples displayed a micromorphology that was successfully described as a fractal structure that can be decomposed into local motifs whose essential features varied with the Cu-doping and/or annealing temperature in agreement with their mentioned influence on the crystallization process of the samples.

Considering the importance of metal nano catalysts, this research tries to apply sputtered nanoparticles as catalyst for growing carbon nanotubes and studies the effect of metals in modifying the catalytic property. One and bilayer Cu and Fe thin films were placed inside a quartz tube reactor to synthesis carbon nanotubes using acetylene gas as carbon source and argon gas for cooling down the reactor from 850 °C to room temperature. By scanning electron microscope images distribution of diameter of multi walled carbon nanotubes has recorded. The amounts of ID/IG obtained from Raman spectroscopy analysis showed the best quality of carbon nanotubes for Cu-Fe bilayer. Both analyses indicate the improve of catalytic effect of one transition metal by another one. On the other hand, multi walled carbon nanotubes are confirmed by both Raman spectroscopy and transmission electron microscopy images. Keywords: Transition metal nano catalyst, TCVD, MWCNT, Raman spectroscopy

Myocardial infarction is one of the major causes of mortality throughout the world. Cardiac scaffolds are tissue-engineered structures for the treatment of myocardial infarction and are employed fo...

This study presents research into the three-dimensional (3-D) surface texture of silver chiral nanoflowers with three-, four- and five-folds spatial symmetry, which were produced using oblique angle deposition method with rotating sample holder. X-ray diffraction (XRD), atomic force microscopy (AFM), and field-emission scanning electron microscopy (FESEM) measurements were carried out in order to study 3-D morphology and structure of the samples at the nanoscale. Obtained results were found to provide an insight into important relationships between the structure of prepared nanoflowers and their properties. Results presented in the paper proved the usefulness of the method for preparation of high-quality, sculptured 3-D nanostructures with pre-designed shapes (with narrower and longer petals) and desired porosity. Specific structure, shape, and length scale of the 3-D deposits can be then verified in simulations for quick characterization of the samples. This analysis helps to understand their functional role in the test surface, in order to evaluate the relation among the 3-D microtextured surface.

In their recent article, Alipour et al. (Res Chem Intermed, 1. doi:10.1007/s11164-016-2594-8) studied the effect of pressure on the morphological characteristics and quality of synthesized graphene from SEM data. Here, the basics of fractal calculations and depth histogram will be explained to avoid such egregious mistakes between using AFM, SEM and stereo SEM images by authors.

This paper analyses the three-dimensional (3-D) surface texture of Cu/Co thin films deposited by DC-Magnetron sputtering method on the silicon substrates. The prepared Cu/Co nanoparticles were used as research materials. Three groups of samples were deposited on silicon substrates in the argon atmosphere and gradually cooled down to room temperature. The crystalline structures and elemental compositions were analyzed by X-ray diffraction (XRD) spectrum with conventional Bragg-Brentano geometry. X-ray diffraction profile indicates that Co and Cu interpenetrating crystalline structures are formed in these films. The sample surface images were recorded using atomic force microscopy (AFM) and analyzed by means of the fractal geometry. Statistical, fractal and functional surface properties of prepared samples were computed to describe major characteristics of the spatial surface texture of Cu/Co nanoparticles. Presented deposition method is a versatile, costeffective, and simple method to synthesize nano- and microstructures of Cu/Co thin films. This type of 3-D morphology allows to understand the structure/property relationships and to investigate defect-related properties of Cu/Co nanoparticles. Presented results confirm the possibility of preparing high-quality Cu/Co nanoparticles via DC-Magnetron sputtering method on silicon substrates.

This paper analyses the three-dimensional (3-D) surface texture of growing diamond nanocrystals on Au thin films as catalyst on p-type Si substrate using hot filament chemical vapour deposition (HFCVD). Rutherford backscattering spectrometry (RBS), atomic force microscopy (AFM), Raman, X-ray diffraction (XRD) and scanning electron microscopy (SEM) analyses were applied also to characterize the 3-D surface texture data in connection with the statistical, and fractal analyses. This type of 3-D morphology allows a deeper understanding of structure/property relationships and surface defects in prepared samples. Our results indicate a promising way for preparing high-quality diamond nanocrystals on Au thin films as catalyst on p-type Si substrate via HFCVD method.

This paper analyses the three-dimensional (3-D) surface texture of Copper oxide nanowires grown on different substrates and in an electric field. Atomic force microscopy, X-ray diffraction and field emission scanning electron microscopy analyses were applied also to characterize the 3-D surface texture data in connection with the statistical, and fractal analyses. This type of 3-D morphology allows a deeper understanding of structure/property relationships and studies the effect of micromorphology on CuO nanowires grown in electric field and the impact of growth direction on their properties. It also provides a compact representation of complex micromorphology information.

The aim of this work is to investigate the three-dimensional (3-D) surface texture of Aliminium doped Zinc Oxide (AZO) thin films deposited by Radio Frequency sputtering method on the quartz substrates. Deposited samples were annealed under argon flux at three different temperatures: 400 °C, 500 °C, and 600 °C, followed by gradual cooling down to room temperature. To characterize the structure of samples X-ray diffraction (XRD) patterns and Rutherford Back Scattering (RBS) spectra were applied. The Scanning electron microscope (SEM) and the atomic force microscope (AFM) were applied to study the samples' surface morphology. Then statistical, fractal and functional surface characteristics were computed. The analysis of 3-D surface texture of AZO thin films is crucial to control the 3-D surface topography features and to correct interpretate the surface topographic parameters. It also allows understanding the relationship between 3-D the surface topography and the functional (physical, chemical and mechanical) properties of AZO thin films.

Cu/Fe thin films were prepared by DC-Magnetron Sputtering system using Cu and Fe targets at room temperature and in the optimized conditions of power and pressure. Using 2 and 3 dimensional atomic force microscope images the surface morphology of samples were studied. The effect of introducing Fe to Cu layer was clearly seen from nanoparticles’ size. UV–visible spectroscopy was applied to investigate the optical properties. The absorption coefficient, the refractive and the absorption indices of thin films at different wavelengths were obtained using reflectance and transmittance spectra. Band gap studies show that when Fe atoms added to Cu layer the amounts of band gap decreases in thicker layers.

In this paper the sputtered gold nanoparticles (NPs) deposited by Radio Frequency-Plasma Enhanced Chemical Vapor Deposition (RF-PECVD) method on the glass substrates in trace of amorphous hydrogenated carbon (Au NPs @ a-C: H) were analyzed to study the three-dimensional (3-D) surface texture. The prepared Au NPs @ a-C: H films were used as research materials. The synthesis of samples was carried out in different powers from 80 to 120 W while all other parameters were kept constant. The X-ray diffraction patterns and UV–vis spectra were applied to study the structure and Localized Surface Plasmon Resonance (LSPR), respectively. An atomic force microscope in a non-contact mode was used to record the sample surface images then the fractal geometry was studied. The images were numerically processed to calculate the Areal Autocorrelation Function (AACF), which was used to determine the anisotropy ratio Str, and to compute the Structure Function (SF). The log–log plots of the latter were used to calculate fractal properties of the studied surfaces, such as fractal dimension D, and pseudo-topothesy K. The analysis of 3-D surface texture was helpful in optimizing the functional performance of the thin film.

Ab-initio study of electronic, magnetic, elastic and optical properties of full Heusler Co2MnSb is performed in the framework of the Density Functional Theory to obtain the associated parameters. Equilibrium lattice parameter is calculated 6.03 A. Studying the electronic properties of compound confirms its half-metallic property, whereas spin polarization at Fermi level is 100 %. This compound in the minority spin channel is a semiconductor with a calculated gap of 0.623 eV. Also, elastic properties of the compound including bulk modulus B, shear modulus G, Young’s modulus E and Poisson’s modulus υ are calculated. Investigation of the elastic properties of Co2MnSb indicates the elastic stability is greatly anisotropic. Besides, it is shown that the Co2MnSb is mechanically a ductile compound. Spin magnetic moment is obtained 6.0001 that are in good agreement with the previous experimental studies. In addition, in order to optical studies, dielectric function, reflectivity, energy loss function, absorption coefficient and optical conductivity are calculated.

This paper analyses the three-dimensional (3-D) surface texture of Co/CP/X (X = Cu, Ti, SM and Ni, CP: carbonaceous paste) nanoflakes prepared electrochemically using a conventional three electrode system. The surface chemical composition of the samples was investigated by X-ray photoelectron spectroscopy (XPS). Surface images were recorded using scanning electron microscopy (SEM) and analyzed by means of the fractal geometry. Statistical, fractal and functional surface properties of the prepared samples were computed. The statistical functions applied to the SEM data were employed in order to characterise the surfaces topographically (in amplitude, spatial distribution and pattern of surface characteristics). The analysis of the 3-D surface texture of Co/CP/X nanoflakes is essential to control the surface topography and for the correct interpretation of surface topographic features as well as its functional role. It also provides a compact representation of complex micromorphology information.

In the present study, ZnO and Al:ZnO (AZO) thin films were prepared by reactive RF sputtering on quartz substrates at a constant oxygen partial pressure and a typical sputtering power. Films were annealed at different temperatures in argon ambient in the oven to study their various structural and optical properties. It was understood that introducing Al into ZnO structure would affect the ZnO crystalline structure noticeably. It was observed that annealing had great influence on various properties of thin films while ZnO film showed low crystallinity, Al doping into ZnO structure pronounced significant improvement in both crystallinity and particle sizes. It was found that crystal structures, average crystalline sizes, and topology of all thin films were modified enormously by post-annealing. It was shown that films transparency fluctuated by annealing, in which the transparency of AZO thin film annealed at 500 � C was much greater than others. Annealing led to decrease optical band gap of all annealed films from 3.31 to 3.26 eV for ZnO and 4 to 3.4 eV for AZO films. Photoluminescence manifested that blue emission in as-deposited film led to two different blue and violet emissions in all AZO and ZnO films. It was identified that the emission intensity of AZO film annealed at 500 � C was 12 times more than other ZnO and AZO films.

This paper analyses the three-dimensional (3-D) surface morphology of thin films of Fe on Cu nanoparticles (NPs) synthesized by direct-current (DC) magnetron sputtering deposited on glass substrates. Four samples coated with copper and iron and deposited on the glass surface were used as research materials. Thin films were obtained by means of a DC reactive magnetron sputtering method. The copper coating of each sample was 55 nm thick. In addition, the second, third, and fourth samples had a coating of iron, with a thickness of 40, 55, and 70 nm, respectively. The sample surface images were obtained by using an atomic force microscope operating in a contactless mode. The 3-D of the surface samples was divided into motifs of significant peaks and pits using MountainsMap Premium software, which uses the watershed segmentation algorithm. In addition, the highest and lowest points of motifs are localized. The parameters relating to all the segmented motifs consistent with ISO 25178-2:2012 have been generated ...

This paper analyses the thickness influence of Fe on Cu nanoparticles (NPs) synthesised by Direct-current (DC) magnetron sputtering on the three-dimensional (3-D) surface morphology of thin films. The thin films with Cu nanoparticles were deposited on glass substrates then; Fe nanoparticles were added to Cu ones. These nanostructures were investigated at one deposition thickness of Cu and three of Fe (Cu 55 nm, Cu 55 nm/Fe 40 nm, Cu 55 nm/Fe 55 nm, and Cu 55 nm/Fe 70 nm as thin films’ thickness), by means of X-ray diffraction, atomic force microscopy (AFM) and multifractal analysis, in order to evaluate the structure and relation among the 3-D micro-textured surface. The 3-D morphology of surface samples exhibits multifractal features characterized by nano-irregularities of various orders of size and different local densities spread on the surface. The local and global scale properties of 3-D surface geometry were quantitatively estimated using the generalized dimension Dq and the singularity spectrum f(α). The non-uniformity of the nano-irregularities are correlated with the generalized dimension Dq and the spectrum width Δα (Δα = αmax − αmin) of the multifractal spectra f(α). Multifractal approach in correlation with the surface statistical parameters are a sensitive and reliable tool for quantifying the thickness influence of Fe on Cu nanoparticles (NPs) synthesised by Direct-current (DC) magnetron sputtering on the 3D surface morphology of thin films.

In the present work three-dimensional (3-D) surface topography of Cu-Ni nanoparticles in hydrogenated amorphous carbon (Cu-Ni NPs @ a-C:H) with constant thickness of Cu and three thicknesses of Ni prepared by RF-Plasma Enhanced Chemical Vapor Deposition (RF-PECVD) system were investigated. The thin films of Cu-Ni NPs @ a-C:H with constant thickness of Cu and three thicknesses of Ni deposited by radio frequency (RF)-sputtering and RF-PECVD systems, were characterized. To determine the mass thickness and atomic structure of the films, the Rutherford backscattering spectroscopy (RBS) spectra was applied. The absorption spectra were applied to study localized surface plasmon resonance (LSPR) peaks of Cu-Ni NPs (observed around 608 nm in visible spectra), which is widened and shifted to lower wavelengths as the thickness of Ni over layer increases, and their changes are also evaluated by the 3-D surface topography. These nanostructures were investigated over square areas of 1 μm × 1 μm using atomic force microscopy (AFM) and multifractal analysis. Topographic characterization of surface samples (in amplitude, spatial distribution, and pattern of surface characteristics) highlighted 3-D surfaces with multifractal features which can be quantitatively estimated by the multifractal measures. The 3-D surface topography Cu-Ni NPs @ a-C:H with constant thickness of Cu and three thicknesses of Ni prepared by RF-PECVD system can be characterized using the multifractal geometry in correlation with the surface statistical parameters.

In this research, we investigated carbon–nickel composite films prepared by RF-magnetron co-sputtering on quartz substrates using a multi-component target (10 cm in diameter) consisting of pure graphite (99.99%) and strips of pure nickel (approx. 2 cm2 in size) attached to the graphite race track, that corresponds to around 2.5% in area. The substrates were ultrasonically cleaned in acetone bath for 20 min and dried in hot air flow prior to deposition process. The films were grown at room temperature in a deposition chamber evacuated to a base pressure 1 × 10−3 N/m2 and then the constant Argon working pressure of 4 N/m2 was settled and maintained by throttle valve. Deposition was done in constant RF power regime 400 W. The films were deposited for 600 s and then annealed for 2 h in a furnace at the temperature: 300, 500, 800 and 1000 °C under ambient atmospheric pressure.

The elastic, optical, and effective mass properties of CrSb in zinc-blende (ZB) phase were investigated. The calculations were carried out using the full-potential linearized augmented plane wave plus local orbital according to the density functional theory. The results of elastic calculations by generalized gradient approximation and local density approximation approximations indicate that ZB CrSb is a ductile material and its Debye temperature is rather low. Band structure and density of state calculations introduce the ZB CrSb as a half-metal with spin polarization of 100 %. In metal state, 16th and 17th bands cut off the Fermi level. Calculations study the effective mass, Fermi velocity, and Fermi surface at 16th and 17th bands. In continue, optical quantities such as dielectric function, energy loss function, and optical conductivity were investigated.

In this paper, the optical properties of carbon-nickel films annealed at different temperatures 300, 500, 800 and 1000 ° C, with a special emphasis on the absorption edge, were investigated. The optical transmittance spectra in the wavelength range 300-1000nm were used to compute the absorption coefficient. The optical dispersion parameters were calculated according to Wemple and DiDomenico (WDD) single-oscillator model. Photoluminescence (PL) measurements of carbon-nickel films exhibit two main peaks at about 2.5 and 3.3eV which correspond to the fundamental indirect and direct gap, respectively. The field emission scanning electron microscopy (FESEM) showed that the absorption edge in the films was controlled by the nanoparticle size. The films annealed at 500 ° C have minimum indirect optical band gap and maximum disorder.

ZnO thin films of different thicknesses were prepared by thermal evaporation on glass substrates at room temperature. Deposition process was carried out in a vapour pressure of about 5.54 × 10 −5 mbar. The substrate-target distance was kept constant during the process. By XRD and AFM techniques the microstructural characteristics and their changes with variation in thickness were studied. Electrical resistivity and conductivity of samples vs. temperature were investigated by four-probe method. It was shown that an increase in thickness causes a decrease in activation energy.

This paper analyzes the three-dimensional (3D) surface texture of amorphous hydrogenated carbon films with sputtered iron nanoparticles (FeNPs@a-C:H) deposited by a radio-frequency plasma-enhanced chemical vapor deposition method on the quartz substrates. The prepared FeNPs@a-C:H films were used as research materials. The synthesized samples were deposited at four different pressures of 2.5, 3, 3.35, and 3.5 N/m2 in an acetylene gas atmosphere. The Fe and C contents of the thin films were obtained from X-ray photoelectron spectroscopy. The X-ray diffraction profile and electron diffraction pattern indicate that iron nanoparticles with body-centered-cubic crystalline structure are formed in these films. The localized surface plasmon resonance peak that is the signature of the existence of the iron core nanoparticles appears in visible spectra of these films. The sample surface images were recorded using an atomic force microscope operating in a noncontact mode and analyzed to reveal the statistical, fractal, and functional surface properties of prepared samples. Analysis of the 3D surface texture is essential for the correct interpretation of surface topographic features as well as its functional role for the test surface. It also helps to understand the relationship between the surface topography and functional properties.

The densification and the fractal dimensions of carbon–nickel films annealed at different temperatures 300, 500, 800, and 1000°C with emphasis on porosity evaluation are investigated. For this purpose, the refractive index of films is determined from transmittance spectra. Three different regimes are identified, T 800°C. The Rutherford backscattering spectra show that with increasing the annealing temperature, the concentration of nickel atoms into films decreases. It is shown that the effect of annealing temperatures for increasing films densification at T 800°C is greater than the effect of nickel concentrations. It is observed that the effect of decreasing nickel atoms into films at 500°C < T < 800°C strongly causes improving porosity and decreasing densification. The fractal dimensions of carbon–nickel films annealed from 300 to 500°C are increased, while from 500 to 1000°C these characteristics are decreased. It can be seen that at 800°C, films have maximum values of porosity and roughness.

Electrical conductivity of carbon-nickel composite films annealed at temperatures 300, 500 and 800°C is studied over a temperature range of 50–300 K. While the conductivity data above room temperature show extended state conduction, lowering the temperature from 150 to 50 K leads to the Berthelot-type conduction mechanism. It can be seen that the films annealed at 500°C have the maximum conductivity. The extent of the carrier wave function at 500°C has the minima 2.87 × 10−7 cm and 2.45 × 10−7 cm in octahedral-metal stretching vibrations and intrinsic stretching vibrations of the metal at the tetrahedral site, respectively. The average distances between two vibration octahedral and tetrahedral sites at 500°C also have the minima 1.13 × 10−7 cm and 0.97 × 10−7 cm, respectively. The Berthelot temperature for films annealed at 800°C has the minimum of 94.3 K.

High Vacuum thermal evaporation was used to grow germanium islands on the silicon substrate covered by silicon oxide. The Ge nano-islands were formed by thermal annealing at different temperatures from 500 °C to 700 °C. Formation of islands was studied by various analytical techniques. The thickness of Ge layer was determined by rutherford backscattering spectroscopy (RBS). Also, combined with channeling technique, the composition and probable contaminants during synthesis processes were investigated. To explore the islands size and shape, both atomic force microscopy (AFM) and field emission scanning electron microscopy (FESEM) were used. Then the topographical images of surfaces were studied by AFM. The outcome of experimental evaluations of growth mechanism has indicated that with increasing the annealing temperature up to 700 °C, Ge islands were appeared from a uniform layer. Moreover, the statistical assessments of surfaces have shown that the nano-island’s sizes can be varied from several hundred nanometers to 30 nm by growing the annealing temperature. The reduction of the size along with an increase of the number of nano-islands after each thermal treatment is a major factor to prohibit us from seeing their clear images in AFM. The possibility of running statistical estimation on islands, instead, is the powerful tool of extracting and probing the distribution and the shape of Ge island’s peak in AFM images.

In this paper, colloidal silver nanoparticles were prepared by chemical reduction of AgNO 3 and pure Sn in a new and simple method. The type of crystallite lattice and the size of nanopowders were estimated by X-Ray Diffraction (XRD) analysis. The geometric, heterogeneous and mixing structure of synthesized nanopowders were studied by Scanning Electron Microscopy (SEM). Optical properties such as plasmon absorption and frequency of soluble colloidal nanopowders in two solutions of distilled water and oil were investigated by UV-Visible spectroscopy, which was developed to calculate the absorbance spectra of nanoparticles solution containing a size distribution of particles using the Mie theory. Dipole and quadrupole plasmons related to molecular structure of water and oil were found by absorbance spectra. Also, Differential Scanning Calorimetry (DSC) analysis was used for determining the thermal behavior, endothermic and exothermic peaks of Ag nanopowder.

In recent article [Ali Gelali. Azin Ahmadpourian. Reza Bavadi. M. R. Hantehzadeh. Arman Ahmadpourian. J Fusion Energ DOI 10.1007/s10894-012-9510-z], Ali Geleli et al. studied the PSD and RMS Roughness parameters in Titanium Nitride thin films by AFM data and used the computed fractal dimension value of micrographs to describe the surface morphology of thin films. Here, the correct form of equations and relationship between PSD and RMS will be discussed.

Growth of thin layers of compound semiconductors such as GaAs and Al x Ga 1− x As was obtained by Liquid Phase Epitaxy (LPE) at 838–828 ° C in thickness range of 0.1–4.3 μ m which was estimated by Scanning Electron Microscopy (SEM). By Secondary Ion Mass Spectroscopy (SIMS) measurements, type of impurity atoms and their density and uniformity with respect to thickness were measured. In this way we are sure that variation of impurity atoms such as Si, Te, Sn and Ge indicates that epilayers were formed uniformly and it demonstrated that the LPE growth was a suitable way to obtain a good quality of epitaxy layers. Amount of composition parameter x in the compound semiconductor Al x Ga 1− x As was measured which varies from 0.13 to 0.4. In-depth profiles of SIMS indicated that Al atom can be replaced by Ga atom in the GaAs crystalline structure.

In this study, we propose new approach to study on hydrogen implantation into SiC crystalline structure and its effect on thermal oxidation. This paper has investigated on effects of hydrogen implantation into the surface structure of 6H-SiC crystal before and after thermal oxidation in oxygen ambient. H ions were implanted in SiC with dose of 1×10 16 atoms/cm 2 and energy of 15 keV. AFM results of implanted and non-implanted areas show that roughness in the implanted area is more than the non-implanted but, we could not observe any evidence of implanting effect in the nano scrapes which were created during polish process. Also, crystal quality, effect of H implantation and depth of maximum concentration were determined by RBS- Channeling. Moreover, it shows that the collision of H ions has affected on the SiC atoms. Distribution and dose of H ions were estimated by ERD technique. Furthermore, bonding between SiC atoms was investigated in implanted and non-implanted areas by FTIR technique. In addition, FTIR results in two areas show a significant difference between both areas before and after oxidation in oxygen ambient.