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Shape memory alloys (SMAs) are potential materials in various areas such as engineering and medicine, and their applications are being studied for practical use. SMAs show competence in their main material properties in response to their working environment or external stimuli. Machining of NiTiCu10 SMAs is difficult using traditional machining because of their wide-ranging mechanical properties like high toughness, strength, and sensitivity to phase transformation temperature. Nonconventional machining methods such as electro-discharge machining (EDM) are suitable for effective machining SMAs. The work material NiTiCu10 SMA has been used in this study, and processed using the vacuum induction melting (VIM) technique. The addition of copper leads to increase in the martensitic transformation temperatures. This paper focuses on the electro-discharge drilling (EDD) of NiTiCu10 SMA using copper tool electrode. Experimental analysis of performance criteria has been evaluated by conducting experiments following one factor at a time (OFAT) approach. Machining features such as material removal rate (MRR), tool electrode wear rate (TEWR), and surface roughness (SR) have been studied by considering pulse current ( I p ), gap voltage ( V g ), pulse on time ( T on ), pulse off time ( T off ), and rotational speed of tool electrode (N). Experimental results have shown that machining at the highest I p of 12 A yields the highest MRR with the value of 4.077 mm3/min, whereas mcahining at T on of 15 μ s yields the lowest TEWR with the value of 0.031 mm3/min. The lowest SR is 2.8 μ m achieved at the lowest T on of 15 μ s. Surface morphology is significant in quality evaluation in the manufacturing, and building industries because it directly determines the mechanical performance of parts, and the service life of products. Morphological investigation via scanning electron microscope (SEM) has confirmed the formation of craters, debris, microcracks, and resolidified layers. The benefit of this study has been that we have been able to select the range of significant control factors, and predict their levels, for decisive experimentation. [ABSTRACT FROM AUTHOR]

CuO:ZnO nanocomposite photocatalyst with tunable ratios of CuO was synthesized using a low-temperature-assisted co-precipitation method, which is suitable for industrial-scale production. Analytical techniques, including XRD, FE-SEM, HR-TEM, FTIR, XPS and UV–Vis, were utilized to investigate the structure, morphological characteristics, chemical composition and optical properties of the CuO:ZnO nanocomposite. The XRD analysis reveals that the samples exhibit a single phase, characterized by a wurtzite hexagonal structure of ZnO and a monoclinic structure of CuO. The average crystal size changed from 37.3±8.8nm to 24.6±6.9nm when CuO varied from 0% to 5% in the CuO:ZnO nanocomposite. The scanning electron microscope (SEM) images reveal that the nanocomposite particles exhibit a high degree of uniformity, with an average size of approximately 50nm. HR-TEM shows the width of lattice plane families consistent with X-ray diffraction for CuO and ZnO materials. The ZnO exhibits a unique hexagonal shape. Furthermore, there is a slight correlation between the CuO fraction and an increase in grain size. FTIR analysis revealed the specific vibrational modes of ZnO and CuO at wavenumbers of 564, 619, 651, 673 and 488, 607cm−1, respectively. XPS shows secondary valences of Cu and Zn indicating the formation of CuO and ZnO while the high Ov peak indicates the presence of Oxygen defects in the crystal lattice. The absorption results clearly demonstrate the presence of two absorption edges corresponding to ZnO and CuO, as well as the broadening of the absorption spectrum of the nanocomposite sample up to a wavelength of 840nm. The photocatalytic degradation of RhB yielded remarkable outcomes, as the concentration of RhB declined by 98.6% after 20min of illumination using a CuO:ZnO (3:97) nanocomposite. The photocatalytic efficiency is significantly influenced by changing the CuO ratio in CuO:ZnO nanocomposites. This can be attributed to the tradeoff between the effectiveness of the heterogeneous contact layer and the limited ability of CuO to catalyze photochemical reactions. Based on the scavenger test, hydroxyl and superoxide radicals are primarily responsible for the decolorization of RhB dye. Results of evaluating the reusability and stability of the material show that, after fifth recycling, the decomposition efficiency still reaches over 90% after 30min of illumination. [ABSTRACT FROM AUTHOR]

Nanoparticles of zinc selenide (ZnSe) were produced by an innovative, uncomplicated, and extremely rapid process that took no longer than a few seconds. For the production of zinc ions, zinc chloride was utilized, and selenium was used for the production of selenium ions. The effect of Zn to Se ions ratio on optical properties has been examined. The prepared nanoparticles were tested and characterized by using transmission electron microscope TEM, scanning electron microscope SEM and UV–Visible spectroscopy. The morphological results revealed that the ZnSe has a spherical shape with mean diameter around 15 nm and the band gap of the ZnSe increases with increasing the Zn content in the sample. The prepared materials were tested as antibacterial agent. [ABSTRACT FROM AUTHOR]

BiFeO3–BaTiO3 is a promising lead-free piezoelectric ceramic, exhibiting high Curie temperature and superior electrochemical characteristics. In this work, (1 − x) BiFeO3–xBaTiO3 (BF–xBT, x = 0. 2 6 , 0.28, 0.30, 0.32, 0.34, 0.36) ceramics were fabricated using the conventional solid-state reaction method through precise composition control. Multiple characterization techniques, including X-ray powder diffraction (XRD), scanning electron microscope (SEM), and electrical property testing systems, were applied to systematically examine the crystallographic structure, microstructure, as well as the dielectric, ferroelectric and piezoelectric properties of the BF–xBT ceramics. The XRD results confirm that all compositions exhibit a typical perovskite structure, transitioning from a single rhombohedral phase to a rhombohedral–cubic phase mixture as the BT content increases. SEM shows apparent core–shell microstructures in the ceramics. Notably, the results demonstrated that the BF–0.30BT ceramic exhibits the maximum piezoelectric constant ( d 3 3 ) ∼ 2 1 7 pC/N, while the BF–0.34BT ceramic displays the maximum converse piezoelectric constant (d 3 3 ∗) ∼ 3 2 3 pm/V, which highlights the suitability of BF–BT ceramics for high-performance piezoelectric applications. [ABSTRACT FROM AUTHOR]

The lead-free ceramics (1 − x)(0.94 Bi 0. 4 7 Na 0. 4 7 Ba 0. 0 6 TiO3-0.06BiAlO3)- x AgNbO3 (denoted as BNBTA- x AN) were synthesized via a solid-state sintering method. The effect of AgNbO3 doping amount on dielectric properties of the ceramics was studied systematically. X-ray diffraction (XRD), scanning electron microscope (SEM) and Raman spectroscope were used to detect the structure of the ceramics. Temperature-dependent dielectric spectra, frequency-dependent dielectric constant and alternating current (ac) electric conductance at various temperatures were measured. The doping of AgNbO3 greatly reduces dielectric constant around Curie temperature and thus enhances the temperature stability of the dielectric constant. The ceramic BNBTA-0.03AN exhibits excellent temperature-stable dielectric properties with temperature coefficient of capacitance (TCC) ≤ ± 15% between 55∘C and 418∘C with temperature window 363∘C and small changes of dielectric constant and dielectric loss from 100 Hz to 1 MHz at different temperatures. The obtained ceramics are expected to be used in high-temperature capacitors due to its excellent temperature stability. [ABSTRACT FROM AUTHOR]

This research aims to prepare a nanocolloidal solution of gold and gold capped with PVA by chemical reduction method by sodium tri-citrate as a reducing agent and using gold chloride as a source of gold ions in aqueous solution at room temperature (RT). The prepared materials were diagnosed by scanning electron microscope (SEM) with the elemental composition analysis by energy dispersive X-ray (EDX), as well as the X-ray diffraction (XRD). The obtained results showed that the shape of the prepared particles is spherical with enhanced diameters close to 10 nanometers and with good scattering. [ABSTRACT FROM AUTHOR]

In this research, the minimum amount of bio-degradable coconut oil mixed with pressurized air (oil-mist) was first used as dielectric fluid in near-dry WEDM to promote eco-friendly cutting processes. The kerf width (KW), cutting speed (CS), and wire wear ratio (WWR) of coconut oil-mist and demineralized water-mist near-dry WEDM of Monel-K500 alloy have been compared by Taguchi L27 orthogonal array. Experiments were conducted using operating parameters such as air pressure, the flow rate of mixing coconut oil, spark current, pulse duration, and pulse interval. The surface topography of the KW and wire tool surfaces of both near-dry processes are also compared using the scanning electron microscope (SEM) tests. The KW and WWR of the coconut oil-mist process are 6.82% and 15.49% lower, and CS is 21.71% higher than the water-mist process. The contribution of each parameter to responses was also comparatively analyzed. The overall cutting characteristics of coconut oil-mist near-dry WEDM are better than the water-mist process. [ABSTRACT FROM AUTHOR]

The Ni 1 − x CoxTiO3 (0 ≤ x ≤ 1) solid solution powders were prepared by an aqueous sol–gel method. The structural, optical, magnetic and ferroelectric properties of NiTiO3 were investigated by X-ray diffraction, scanning electron microscope, UV–Vis absorption, vibration samples magnetometer and ferroelectric test system. The X-ray diffraction analysis revealed that prepared materials were in a single phase with rhombohedral structure with x up to 1. The increasing Co content resulted in decreasing of tolerance factor and increasing of the lattice constant. The crystalline size increased with an increase of Co content. The optical bandgap value of solid solution increased from 2.23 eV for NiTiO3 to 2.36 eV for CoTiO3. The magnetic hysteresis loop results indicate that all samples showed paramagnetic state at room temperature. A correlation between magnetization values and composition of the materials was observed with magnetization values which increased with increasing of CoTiO3 content in solid solution. Ferroelectric polarization analysis showed that the polarization of the Ni 1 − x CoxTiO3 solid solution depended on x value and reached the maximum with x = 0. 4. [ABSTRACT FROM AUTHOR]

To create a (POT–CSA/ZnO) nanocomposite, a chemical oxidative polymerization of O-toluidine was carried out in the presence of nano ZnO. This step took place throughout the synthesis. In the attendance of hydro chloric acid (HCl) and ammonium persulfate (APS) as an oxidant and camphor solfunic acid (CSA) as a dopant, polymerization can be accomplished by using a monomer mixture with an equal molar ratio. Scanning electron microscope (SEM), X-ray diffraction (XRD), Fourier transform-infrared spectroscopy (FTIR), and UV–Vis spectroscopy were utilized in the procedure of characterizing the material. The results displayed that the polymer film revealed both excitonic transition π – π and to π − π * transition. The semiconducting character of the composite can be confirmed by its electrical conductivity. [ABSTRACT FROM AUTHOR]

This paper proposes a generative model and transfer learning powered system for classification of Scanning Electron Microscope (SEM) images of defective nanofibers (D-NF) and nondefective nanofibers (ND-NF) produced by electrospinning (ES) process. Specifically, a conditional-Generative Adversarial Network (c-GAN) is developed to generate synthetic D-NF/ND-NF SEM images. A transfer learning-oriented strategy is also proposed. First, a Convolutional Neural Network (CNN) is pre-trained on real images. The transfer-learned CNN is trained on synthetic SEM images and validated on real ones, reporting accuracy rate up to 95.31%. The achieved encouraging results endorse the use of the proposed generative model in industrial applications as it could reduce the number of needed laboratory ES experiments that are costly and time consuming. [ABSTRACT FROM AUTHOR]

The rising demand for silver nanoparticles obtained by green method has made it necessary to search for readily available bio-materials that can serve as sustainable bio-reductant and stabilizers. Pennisetum purpureum is a readily available tropical plant commonly used as food, feed for livestock, and thermal energy production. In this study, extract from the leaves of Pennisetum purpureum was explored to prepare silver nanoparticles (Perp-AgNPs). The structural and optical properties of the particles were studied with scanning electron microscope, Ultraviolet-Visible spectrophotometer, Fourier transform infrared (FTIR) spectrometer and X-ray diffractometer. The antioxidant property of the Perp-AgNPs was studied by investigating its ability to scavenge 2,2'-azino-bis (3-ethylbenzothiazoline-6-sulfonic acid) (ABTS) free radical. Enhanced activity of 83% was obtained by 1 mg/mL of the Perp-AgNPs after 10 min of scavenging. In addition, IC 5 0 = 0. 1 7 9 mg/mL was observed by the Perp-AgNPs. The antimicrobial property of the Perp-AgNPs was investigated against broad range of microorganisms, namely, Escherichia coli, Pseudomonas aeruginosa, Klebsiella pneumoniae, Streptococcus mutans, Bacillus subtilis, Methicillin resistant Staphylococcus aureus, Salmonella typhi and Candida albicans. The minimum inhibitory concentration values ranged from 0.313 to 1.25 mg/mL with Psuedomonas aeruginosa, Candida albicans and Methicillin resistant staphylococcus aureus being the most susceptible. The Perp-AgNPs also demonstrated the ability to enhance the efficacy of standard antibiotic and antifungal agents. The antimicrobial combinatory effects were synergy and partial synergy against the selected microorganisms. The results from the study show that silver nanoparticles prepared with leaves extract of Pennisetum purpureum have adequate antioxidant and antimicrobial properties for applications in nanomedicine. [ABSTRACT FROM AUTHOR]

In this work, three samples of thin films were prepared from semiconducting nanomaterials by the chemical bath method, where a thin film of lead sulfide PbS, Cadmium zinc sulfide CdZnS and PbS/CdZnS was prepared. The optical properties and surface formation of the bilayer film were studied and investigated by scanning electron microscope and UV–Visible spectrometer. It was observed through the scanning microscope image that the surface of the thin film is composed of CdZnS material in the form of nanowalls that cover the PbS nanoparticles completely, forming a core–shell structure. The transmittance and absorption spectra of the prepared films, as well as the direct and indirect energy gaps, were measured. It was observed that there is a shift in the absorption and transmission spectra of the PbS film after coating it with CdZnS layer. The magnitudes of the direct and indirect energy gaps of the bilayer film are 1.8 eV and 1.5 eV, respectively. [ABSTRACT FROM AUTHOR]

Electrical discharge machining (EDM) is a non-conventional process utilized for machining electrically conductive materials which cannot be machined by conventional processes. This paper is focused on modeling and optimization in electrical discharge machining (EDM) of UNS T30407 steel. The variables such as pulse on time (Ton), pulse off time (Toff), and current will influence the material removal rate (MRR) and surface roughness (Ra) which were taken as response variables. Experimental data were collected as per the central composite design (CCD) matrix of response surface methodology (RSM) approach and mathematical models have been developed for both the response variables. The analysis of variance (ANOVA) was employed to determine the significant machining parameters and optimize the input parameters for both the responses (MRR and Ra). The statistical adequacy of the models is tested with the help of ANOVA. The optimum parametric combination for maximum MRR and smaller Ra (highest surface finish) was found. The surface characteristics of the machined surface were investigated by a scanning electron microscope (SEM). [ABSTRACT FROM AUTHOR]

Bionanotechnology approaches are used by researchers to create nanoparticles and nanomaterials in an environmental friendly and cost-effective manner. Because of biologically active plant secondary metabolites that aid in green synthesis, as well as their specific biological applications, biosynthesized nanoparticles are gaining traction. This work describes a simple, eco-friendly, dependable and cost-effective method for making silver nanoparticles from aqueous leaf extract of Psychotria octosulcata, as well as their anti-inflammatory properties in vitro. UV-Visible spectroscopy, Fourier Transform Infrared spectroscopy (FTIR), X-ray diffraction (XRD), Scanning electron microscopy (SEM) and Zeta potential (ZP) were used to analyze the biosynthesized Psychotria octosulcata silver nanoparticles. Under a scanning electron microscope, the silver nanoparticles had a spherical shape and sizes ranging from 1 to 100 nm. The peaks from the Fourier Transform for the functional groups C=O, –C=C, C–H and OH in the infrared spectroscopy spectra of silver nanoparticles demonstrate the stability of the produced silver nanoparticles. The particles were crystalline and had a face-centered cubic structure with broad peaks in nature, according to the XRD studies. Protein denaturation was used to test the anti-inflammatory activity of the synthesized silver nanoparticles in vitro. [ABSTRACT FROM AUTHOR]

The hot aqueous extract of E. camaldensis leaves as a degradable agent and copper nitrate as a copper source with cold plasma was used in this work to present an easy and green technique for copper oxide nanoparticles (CuO NPs) synthesis. UV-Vis absorption spectroscopy, X-ray diffraction (XRD), Atomic Force Microscopes (AFM), and Scanning Electron Microscopes (SEM) were all used to determine the production of copper oxide nanoparticles (SEM). The energy gap was 4.9 eV, and the average crystalline size of CuO NPs evaluated using the Scherrer equation was 15.06 nm, according to the X-ray diffraction pattern (XRD). CuO NPs had a grain size of 70.63 nanometers, according to AFM morphology study. Finally, the effect of copper oxide nanoparticles on Gram-positive and Gram-negative bacteria, as well as fungi, was studied. [ABSTRACT FROM AUTHOR]

In this study, a novel medicinal plant, Lagerstroemia indica, was used to extract Silver Oxide Nanoparticles (Ag2O-NPs) and the in vitro anticancer potentials of synthesized Ag2O-NPs were evaluated on human cancer cell lines. Ultraviolet–Visible (UV-Vis) spectroscopy confirmed the formation of Ag2O and the particle size of 9.98 nm was confirmed by X-Ray Diffraction (XRD) analysis. Scanning Electron Microscope (SEM) images showed spherical-shaped NPs. The anticancer potential determined by 3-(4, 5-dimethylthiazol-2-yl)-2, 5-diphenyl tetrazolium bromide (MTT) assay showed significant cytotoxic potential against breast cancer (MCF-7) and cervical cancer (HeLa) cell lines with the IC50 concentrations at 46.22 μ g/ml and 39.39 μ g/ml, respectively. Ag2O-NPs showed a subsequent reduction in Mitochondrial Membrane Potential (MMP) and increased level of Reactive Oxygen Species (ROS). The dual staining of Ag2O-NPs showed a greater number of early apoptotic and late apoptotic cells as compared to the standard drug camptothecin. Real-Time quantitative Polymerase Chain Reaction (RT-qPCR) determined an upregulated level of Caspase3 and p53. Thus, the present study indicates that Ag2O-NPs synthesized from L. indica may be used as an anti-cancer drug after further in vivo trials. [ABSTRACT FROM AUTHOR]

Friction stir welding is a contact welding process that uses the heat generated by friction to fuse two different materials. This work is focused on the development of micro-friction stir welding which is carried out for very thin sectioned materials of thickness 1000 μ m or less. Friction welded butt-joints were successfully produced for 0.8 mm thin AA6061 and SS304 sheets on a semi-automated vertical milling machine using a zero-pin length tool. A mild steel backing plate is used as fixture mechanism to hold the welding sheets on machine. Tool-rotational speed and Tool-travel speed are the weld-parameters examined on mechanical responses such as tensile behavior, micro-hardness and surface-roughness across the nugget-weld zone interface. The maximum tensile strength is obtained at lower weld-parameters. Tensile strength properties of AA6061-T6/SS304 joints were approximately found to be 25% lower than that of the AA6061-T6 alloy base metal. Maximum hardness value of 93HV and minimum roughness value of 2.808 μ m are observed for higher tool speeds at nugget-weld zone interface due to the formation of intermetallic phases. Microstructural behavior is studied on weld-parameters using scanning electron microscope and energy dispersive X-ray analyzer. Very thin intermetallic layers (consisting of Fe2Al5, FeAl3 and FeAl2 phases) were observed in stainless steel/aluminum interface. [ABSTRACT FROM AUTHOR]

Many researchers have developed models which are capable of analyzing the effects of process parameters on the responses of different welding operations carried out on 17-4 PH steel which bears extensive properties and have wide range of applications. The weld quality of any material plays a major role in determining the strength of the joint. Hence a proper and procedural analysis has to be made in order to assess the quality of the weld. This could happen only when the analysis of the weld quality is reviewed. Here in this work, RSW of special kind of stainless steel is welded considering the very important parameters which alter the response characteristics to a greater extent. From literature it is evident that no full proof plan is available to conduct welding process of any kind. Hence, an attempt is made to design experiments of welding on the material with the help of Taguchi method and the same is analyzed using ANOVA for the superiority of the parameters on basis of which the optimization of responses can be done. The weld quality can be assessed using one of the responses known as tensile test which determines the breaking load required for the failure of the welded specimen. The micro structural analysis is then carried out using Scanning Electron Microscope which yields the results of failure analysis. It can be clearly seen from the results that the electrode force is the most effecting factor which behaves linearly and then the weld current which drastically or nonlinearly change the characteristics of the response (tensile strength). The micro structural analysis shows that the dimple and ridges are present at the break point which is the evidence for the ductile property of the material. From the pictures of the SEM results, the even distribution of the secondary phase particles is clearly visible, this is again the evidence for the ductile property or the increase in the yield strength. Also pores and cracks are visible but up to a very smaller extent, hence more resistance of the joint for breaking when the load is applied can be seen. [ABSTRACT FROM AUTHOR]

The NiTiO3 ceramic was synthesized in nanostructured form by citrate gel method. The phase structure, microstructure and magnetic properties of synthesized compounds were investigated by X-ray diffraction (XRD), scanning electron microscope and vibrating sample magnetometer. Williamson–Hall plot was used to calculate the crystallite size and microstrain of sample. The XRD analysis showed the formation of rhombohedral crystal structure of synthesized powders. The crystallite size is about 35 nm and microstrain is 5. 9 × 1 0 − 4 . The optical band gap was estimated from UV-Visible spectrum with value of 2.43 eV. The NiTiO3 samples showed coexistence of ferroelectric and antiferromagnetic properties at room temperature. [ABSTRACT FROM AUTHOR]

The design of the lithium polymer battery with excellent performance needs proper exploration of the materials. Poly(methyl methacrylate) (PMMA)-hosted solid nanocomposite polymer electrolyte systems are prepared by solvent-casting technique. A fixed amount of propylene carbonate (PC) is used as a plasticizer, barium titanate (BaTiO 3) as a nanofiller and lithium hexafluorophosphate (LiPF 6) as a dopant salt. The characterization of nanocomposite solid polymer electrolyte (SPE) was carried out using scanning electron microscope (SEM), and the outcome revealed the formation of a three-dimensional network with dispersed nanofillers. The dielectric constants and ionic conductivities for different wt.% of nanofiller with different temperature ranges are measured by impedance analyzer. It is observed that for 15 wt.% of nanofiller-mixed electrolyte sample, a highest dielectric constant of 5166 and a maximum ionic conductivity of 3. 9 × 1 0 − 4 S ⋅ cm − 1 are achieved. [ABSTRACT FROM AUTHOR]

Traveling Wire Electro-Chemical Spark Machining (TW-ECSM) process is a new innovative thermal erosion-based machining process suitable for cutting electrically nonconductive materials using tool electrode in the form of wire. This article attempts experimental modeling of TW-ECSM process using a hybrid methodology comprising Taguchi methodology (TM) and response surface methodology (RSM). The experiments were carried out on borosilicate glass using L 2 7 orthogonal array (OA) considering the input parameters like applied voltage, pulse on-time, pulse off-time, electrolyte concentration and wire feed velocity along with process performances such as material removal rate (MRR), surface roughness (R a) and kerf width (K w ). The interaction influence of input parameters on process performances was also discussed. Further, multi-objective optimization (MOO) of response performances of TW-ECSM process is executed using a coupled approach of grey relational analysis (GRA) and principal component analysis (PCA). The optimal process parameter setting illustrates the improvement of MRR by 171%, diminution of Ra and K w by 27% and 8% against the initial parameter settings. Moreover, irregular cutting of kerf width and surface characteristics were also scrutinized using scanning electron microscope (SEM). [ABSTRACT FROM AUTHOR]

The uniformity, elasticity and hydrophobicity of methyltrimethoxysilane (MTMS)-based silica aerogels, which were prepared by using dimethyl sulfoxide (DMSO) as the solvent, were investigated. The as-prepared silica aerogels were characterized by means of scanning electron microscope, Fourier transform infrared, contact angle/interface system and electronic universal testing machine. The hydrophobicity of the MTMS-based silica aerogels could be adjusted by tuning the MTMS/DMSO molar ratios. The water contact angle of the MTMS-based silica aerogels could be as high as 160.2∘, suggesting its superhydrophobic property. It was found that all the MTMS-based silica aerogels had the typical three-dimensional porous structure. The failure strain of MTMS-based silica aerogels could be as high as 66.14%. [ABSTRACT FROM AUTHOR]

Zinc oxide (ZnO) nanostructured seed layer was grown by successive ionic layer adsorption and reaction (SILAR) method on glass substrate. The as-prepared nanostructured seed layer was characterized by X-ray diffraction (XRD) and scanning electron microscope (SEM) for its structure and surface morphology. XRD results showed a ZnO seed layer growth oriented along the (100) direction. Study of surface morphology showed ZnO nanocrystal clusters with hexagonal shape. ZnO nanorods (NRs) have been grown over the as-prepared ZnO nanostructured seed layer by immersing seed layer substrate in a chemical bath. It has been found that the morphology of the nanostructured seed layer is a key influencing factor for the growth of vertical ZnO NRs. In our growth method, we were successful in growing vertical NRs with diameter of about 100–240 nm with perfect hexagonal shape. The transmittance studies were carried out to analyze the optical bandgap of the as-grown ZnO nanorods. [ABSTRACT FROM AUTHOR]

Micro-Electro Discharge Machining (μ -EDM) is one of the nonconventional micro-machining processes in which electrical discharges are produced between the micro-sized electrodes — tool and workpiece immersed in dielectric fluid. The electrical discharges thus produced remove the workpiece material through melting and vaporization process and results in the creation of micro-craters. This paper focuses on machining of micro-channels on copper alloy — phosphor bronze plate using μ -EDM. Various micro-channels have been machined on phosphor bronze with input parameters: voltage, capacitance and pulse on-time varied at four levels. The experimental layout plans were designed with robust design technique — Taguchi-based L 1 6 orthogonal array and the process parameters were optimized using optimization technique — Grey Relational Analysis (GRA). The dimensional aspects — depth, width, profile and surface roughness of machined channels were selected as output responses. The experimental results show that the parameters have individual and combined effect on responses. Analysis of Variance (ANOVA) technique has been used to explore the effect of parameters on responses. Detailed surface morphology of the machined features has also been analyzed using scanning electron microscope (SEM) and noncontact optical profiler images. As an extension of machining channels, Y-shaped channel has been machined on copper alloy which can be used for micro-fluidic applications. [ABSTRACT FROM AUTHOR]

In this work, the effects of Fe/Ni co-doping on structural and optical properties of TiO2 thin films were investigated by the X-ray diffraction, scanning electron microscope and UV-visible spectroscopy. The optical properties of transmittance, extinction coefficient, refractive index, real and imaginary parts of dielectric constant of the thin films, prepared by spray pyrolysis, revealed that the absorption in visible region increases due to the influence of Fe/Ni co-doping. The widening of the gap energies is observed as a result of doping. The increased optical gap as a consequence of doping can be explained by decreasing the size of nanoparticles, as confirmed by SEM and increasing the formation of oxygen vacancies as a result of Ni 2 + substitution to Ti 4 + and appearance of the Burstein–Moss effect. [ABSTRACT FROM AUTHOR]

Nanocrystalline SnO2 powder has been successfully synthesized by using tin(II) chloride dihydrate (SnCl 2 ⋅ 2 H2O), distilled water and liquid ammonia by the simple chemical co-precipitation method at room temperature using different SnCl 2 ⋅ 2 H2O molar concentration of 0.3 M, 0.4 M and 0.5 M. The structural properties of the prepared SnO2 and transition metal doped SnO2 nanoparticles has been studied using X-ray diffraction method and scanning electron microscope. The composition of the powders has been analyzed using energy dispersive X-ray analysis. The XRD pattern of the SnO2 nanoparticles indicates the formation of single-phase rutile tetragonal structure. The grain size is found to be in the range of 3–7 nm and is found to increase with increasing SnCl2 molar concentration. The absorption spectra revealed that the bandgap decreased from 3.74 eV to 3.59 eV with increasing SnCl2 molar concentration. The photoluminescence spectra of SnO2 nanoparticles showed a visible broad luminescence band in the region of 385–430 nm. The magnetic studies have been carried out using the hysteresis loop obtained from a vibrating sample magnetometer. The SnO2 samples using 0.3 and 0.4 SnCl2 molar concentration exhibited ferromagnetic behavior whereas the SnO2 sample prepared using 0.5 M SnCl 2 ⋅ 2 H2O exhibited paramagnetic nature. [ABSTRACT FROM AUTHOR]

Full-color three-dimensional (3D) printing technology is a powerful process to manufacture intelligent customized colorful objects with improved surface qualities; however, poor surface color optimization methods are the main impeding factors for its commercialization. As such, the paper explored the correlation between microstructure and color reproduction, then an assessment and prediction method of color optimization based on microscopic image analysis was proposed. The experimental models were divided into 24-color plates and 4-color cubes printed by ProJet 860 3D printer, then impregnated according to preset parameters, at last measured by a spectrophotometer and observed using both a digital microscope and a scanning electron microscope. The results revealed that the samples manifested higher saturation and smaller chromatic aberration (Δ E) after postprocessing. Moreover, the brightness of the same color surface increased with the increasing soaked surface roughness. Further, reduction in surface roughness, impregnation into surface pores, and enhancement of coating transparency effectively improved the accuracy of color reproduction, which could be verified by the measured values. Finally, the chromatic aberration caused by positioning errors on different faces of the samples was optimized, and the value of Δ E for a black cube was reduced from 8.12 to 0.82, which is undetectable to human eyes. [ABSTRACT FROM AUTHOR]

The research investigation reported on the effect of machining parameters on surface roughness (Ra) in electric discharge drilling of Inconel 718. Machining was done by using a copper tool electrode. Machining was conducted by considering different process parameters viz. tool diameter, discharge current, pulse on time, pulse off time, tool rotation and depth of hole. Optical surface profiler was used to measure surface roughness of drilled hole in work-piece. Design of experiment was created by Taguchi method based L18 orthogonal array. For minimum surface roughness, optimum parameters were found using Analysis of variance (ANOVA). Based on analysis, it is found that pulse off time, pulse on time and tool rotation are the most significant parameters that affect the surface roughness. Tool diameter is the less significant parameter that affects the surface roughness. Regression analysis was used to predict a value for minimum surface roughness. The scanning electron microscope (SEM) images were used to identify the microstructure of the drilled hole in Inconel 718 work-piece. Interaction plots and residual plot have been plotted for surface roughness to identify the interaction between parameters and residual errors, respectively. [ABSTRACT FROM AUTHOR]

Biologically synthesized nanoparticles are rapidly evolving because it is cost effective and eco-friendly, this also contributes to its preference over nanoparticles from other sources. In this study, silver nanoparticles were synthesized from Albuca setosa aqueous bulb (ASB) extracts and the biological activities evaluated. The silver nanoparticles were synthesized from ASB extracts using silver nitrate and characterized using UV–visible spectroscopy (UV–Vis), Fourier transform infrared spectroscopy (FTIR), scanning electron microscope (SEM), energy dispersive X-ray spectroscopy (EDX), X-ray diffraction (XRD) and transmission electron microscopy (TEM). The antioxidant activity was determined by evaluating the effect on 2,2-diphenyl-2-picrylhydrazyl (DPPH) scavenging activity, 2,2 ′ -azino-bis (3-ethylbenzthiazoline-6-sulfonic acid diammonium salt (ABTS). The antibacterial potential was investigated on selected Gram positive and Gram negative bacteria while the cytotoxicity was evaluated on MDA-MB-231 breast cancer cells (ATCC HTB-26). Albuca setosa silver nanoparticles (AS-AgNPs) was formed within 60 min reaction time of UV–Vis absorption. The FTIR showed that acid anhydride, alkene, amine, aldehyde, ester, ketone and carbonyl groups contributed to the synthesis of the AS-AgNPs, while SEM and TEM showed stable irregular shaped monodispersed silver nanoparticles with average size of 7 nm. The XRD patterns revealed diffraction peaks at 5 4. 7 8 ∘ , 5 7. 6 3 ∘ , 7 6. 9 1 ∘ , 8 5. 7 5 ∘ and 92.37∘ that was indexed to (1 1 0), (1 1 0), (1 0 0), (1 0 0) and (1 0 0) planes of face-centered cubic (fcc) crystalline structure respectively. The synthesized nanoparticles possess good antioxidant activity with IC50 of 7 8. 8 9 ± 0. 2 and 3 9 7. 1 6 ± 1. 4 μ g/ml for DPPH and ABTS, respectively, and inhibit the growth of Staphylococcus faecalis and Bacillus cereus with MIC of 25 and 15 μ g/ml respectively. AS-AgNPs also revealed higher cytotoxic efficacy against MDA-MB-231 breast cancer cells with IC50 of 6 4. 5 2 ± 1. 1 μ g/ml. AS-AgNPs showed acceptable size and shape of nanoparticles and could therefore be a potential source of antimicrobial and anticancer agents. It can be concluded that the synthesized AS-AgNPs is a good source of anticancer agent with broad spectrum of antibiotic activity. [ABSTRACT FROM AUTHOR]

This study was aimed at evaluating the effect of E-glass fibers (≈ 1.0 mm long, ø = 0. 0 1 7 mm with 1.0 wt.% and 5.0 wt.%) in two (MegacemTM and GlassFillTM) glass-ionomer cements (GIC) to enhance their mechanical properties. The six specimen groups were assigned to MCC, MC1, MC5, GFC, GF1 and GF5, and evaluated after 24 h dry storage and 30 days water storage. The results showed considerable increase in surface roughness and the flexural strength values of both cements in both time intervals, whereas a statistically higher elastic modulus was observed in MC1 24 h (15.3 GPa) and 30 days groups (7.1 GPa). On the contrary, no steady improvement in nano-hardness and yield strength were observed with the addition of chopped glass fibers. The SEM images suggest inadequate adhesion of the fibers to GIC matrix. Reinforcing GICs with short chopped E-glass fibers may not improve all the mechanical properties of GIC. [ABSTRACT FROM AUTHOR]

This paper presents an experimental investigation of the bond strength between carbon fiber reinforced polymer (CFRP) and steel substrate by utilizing the pull-off test and scanning electron microscope (SEM) analysis. A series of pull-off experiments was conducted by using three types of CFRP (CFRP sheets and CFRP laminates with/without woven mesh) and two types of epoxy adhesive (ductile and brittle epoxy adhesive) with/without carbon nanotube (CNT) modification. Pull-off samples with CFRP laminates possess higher (about double) bond strength than that of samples with CFRP sheets, due to the good saturation of fibers in the laminates. The steel-CFRP bond with ductile epoxy adhesive (Araldite 2011) is found to have about 16% higher bond strength when compared to that of brittle epoxy (MBrace Saturant), even though the tensile strength of Araldite 2011 is about 40% less than that of MBrace Saturant. Also, it is shown that modified epoxy with CNTs is more efficient than neat epoxy for bonding CFRP to steel at a moderately elevated temperature, and increasing the bond strength about twofold. [ABSTRACT FROM AUTHOR]

Nanoparticle Lead sulfide was synthesized via simple chemical method and deposited on glass substrates at different substrate temperatures by thermal evaporation technique. The synthesized nanoparticle was analyzed and confirmed by X-ray diffraction (XRD), Scanning electron microscopy SEM with EDX and thermogravimetry. The structural, optical, morphological and electrical properties of the deposited films were studied using XRD, UV-Vis, Raman, SEM with EDX, atomicforce microscopy AFM and Hall Effect measurements. The thickness of the deposited samples was measured using thickness profilometer. The Raman shift in the peak occurs toward lower energy with increasing substrate temperature deposited lead sulfide. The Z-scan study with open aperture was carried out at 532 nm using 5 ns laser pulse on the deposited films which shows that nonlinear absorption arises from saturable absorption process. The deposited film exhibits p-type conductivity in Hall measurement. [ABSTRACT FROM AUTHOR]

Composites of polyvinyl alcohol (PVA) containing silver nanoparticles were prepared using in situ synthesis of nanoparticles. Structure and properties of these composites were investigated using UV-Vis spectroscopy, XRD, DSC, SEM and AFM. The studies show that PVA can reduce the 3 to yield silver nanoparticles and in the process forms bonds with PVA chains. The anti-bacterial properties of these films were studied by qualitative as well as quantitative methods which gave the values of 98% for gram positive and 89% for gram negative bacteria. [ABSTRACT FROM AUTHOR]

In this experimental investigation, the heat transfer coefficients of a shell and helically coiled tube heat exchanger using /water nanofluid under laminar flow condition were studied. The nanoparticles were characterized by X-Ray diffraction (XRD). The /water nanofluid at 0.1%, 0.4% and 0.8% particle volume concentration were prepared by using two step method. The prepared nanofluid was characterized by scanning electron microscope (SEM). It is observed that the overall heat transfer coefficient, inner heat transfer coefficient and experimental inner Nusselt number increase while increasing particle volume concentration and increasing inner Dean number. The enhancement of overall heat transfer coefficient was found to be 7%, 16.9% and 24.2% at 0.1%, 0.4% and 0.8% /water nanofluid respectively when compared with water. The enhancement of tube side experimental Nusselt number was found to be 17%, 22.9% and 28% at 0.1%, 0.4% and 0.8% particle volume concentration of /water nanofluid respectively when compared with water at fixed Dean number. The tests were conducted in the range of 1600 < < 2700, and 5200 < < 8600 under laminar flow condition and counter flow configuration. These enhancements are due to higher thermal conductivity of nanofluid while increasing particle volume concentration and Brownian motion of nanoparticles. It is studied that there is no negative impact on formation of secondary flow and mixing of fluid when nanofluid passes through the helically coiled tube. [ABSTRACT FROM AUTHOR]

This study was carried out to evaluate the environmental application of functionalized carbon nanotubes through the experimental removal of strontium (II) from water. The aim was to find the optimal condition for the removal of strontium from water under different conditions such as initial concentration of strontium, contact time and neutral pH. The functionalized multi wall carbon nanotubes (f-MWCNT) were characterized by FT-IR and scanning electron microscopy (SEM). The adsorption isotherms were correlated to Freundlich and Langmuir models and it was found that the adsorption data could be fitted better by Langmuir model than Freundlich one. The kinetic data shows that the adsorption describes well with the pseudo-second order kinetic model. Functionalized MWCNT can be used as good adsorbent for the removal of the strontium ions from polluted water according to results. [ABSTRACT FROM AUTHOR]

Tin oxide thin films were prepared via spray pyrolysis method. The structural and morphological properties of SnO2 thin films have been investigated using X-ray diffraction (XRD) and scanned electron microscope (SEM) analysis. The XRD pattern confirms the tetragonal rutile structure of SnO2 with preferential orientation along (200) plane. SEM image reveals the nanocrystalline nature of the SnO2 films. SnO2 thin films were subjected to electrochemical tests to study the supercapacitor behavior. Maximum specific capacitance of 168 F/g at a scan rate of 25 mV/s was obtained using 0.5 M KOH as the electrolyte. This is the highest value ever reported for spray deposited tin oxide thin films. [ABSTRACT FROM AUTHOR]

The cathodoluminescence technique (CL) performed in the Scanning Electron Microscope (SEM) offers opto-electronic characterization of some nanostructures and it is a powerful tool for studying the compositional variation or band structure of three-dimensional microscale or nanoscale structures. The major problem of the CL technique is the difficulty of high spatial resolution of the low-dimensional structure. In the present paper we propose a simple Monte Carlo calculation model to describe the interaction of electron beam with AlxGa1-xAs-GaAs nanostructure. This model takes into account the confinement phenomenon in the quantum well by an easy method. The influence of different parameters such as the thickness of barriers, Al mole fraction (x), and the diffusion length are studied. The carrier excess generated during the collision of the incident electron with the atoms of the material (random walk) is calculated taking into account the confinement phenomenon within the quantum well. The radiative recombination of electron-hole pairs is collected as a light (CL signal). [ABSTRACT FROM AUTHOR]

Vanadium carbide (VC) coating is prepared with Thermal Diffusion (TD) method in the salt bath, and its surface-interface microstructures and energy spectrums were observed with Scanning Electron Microscope (SEM) and Energy Dispersive Spectrometer (EDS), respectively, and the distributions of C, V, Cr, Si, Fe, and Mo in VC coating interface are analyzed. Its interfacial and bonding methods are discussed, and the bonding micromechanism of VC coating in its bonding interface by TD process is analyzed. The experimental results show that the structure of coating surface by TD is single-phase, that is composed of V and C elements, and no other elements, the chemical elements such as V, Cr, CSi, Fe, Mo are the grade distributed in its bonding interface; its bonding method is metallurgical status; microhardness of coating-substrate is the grade distribution, which is direct ratio with the V distribution, microhardness of the coating surface is 3050-3200 HV, and the effect of TD process on roughness of cold-working die surface is little. [ABSTRACT FROM AUTHOR]

Oil palm fruit bunch (OPFB) fibre was used as filler in polypropylene-clay nanocomposite (PNC) to study its effect on the mechanical properties of OPFB filled PNC or hybrid polymer nanocomposite (HPNC). The OPFB size was varied at 250 μm, 180 μm, 125 μm and 100 μm. HPNC was prepared by compounding 20 wt.% of OPFB together with PNC. Tensile, flexural and impact test samples were injection moulded from the compounds according to ASTM standards. The experimental results showed that the increase of OPFB size in HPNC has increased the tensile and flexural moduli from 39% to 54% and 33% to 69%, respectively. Meanwhile, the tensile and flexural strengths increased as the OPFB size increases. The elongation at break and impact resistance were not affected by OPFB size. Scanning electron microscope result showed that the fracture surfaces of coarser OPFB filled polypropylene-clay nanocomposite has several mechanisms such as fibre pull-outs, fibre fracture and fibre delamination, whereas the PNC filled with finer OPFB exhibited ductile fracture. [ABSTRACT FROM AUTHOR]

α-Fe2O3 nanoparticles were obtained by a mechanical alloying of micrometer-sized powder at different milling times. Samples were characterized by X-ray powder diffraction, scanning electron microscope (SEM), Mössbauer spectrometry, and vibrating sample magnetometer (VSM). A qualitative and quantitative phase analyses using the Rietveld method have been performed based on the XRD data. The results did not reveal any phase change during the milling. The average particle size decreases with a prolongation of milling times, while the lattice parameters, unit cell volume, and microstrain increase. Mössbauer measurement shows that there are two components, one nanometric and other micrometric. The magnetic hysteresis loops shows that the samples are typical of ferromagnet with superparamagnetic fraction in the material. [ABSTRACT FROM AUTHOR]

This study briefly reports a newly developed nanopatterning technology utilizing a so-called micro droplet jetting system, which can be used in various applications such as nanofabrication. Compared with the conventional methods, this technology has the advantages as follows: it can be manipulated easily and patterned freely as the user requires; furthermore, it shows high-reliability and high-stability with very low cost. The typical specs of the micro droplet jetting system for fabricating nanodevice show as follows: (1) nanoparticle size: 50–60 nm; (2) characteristic wavelength: 400–450 nm; (3) volume of droplet: 6 ppl; (4) size of pixel: 70 μm. In this article, the nanopatterning technology adopting the micro droplet jetting system has been demonstrated to be useful for nanopatterning the pixels which consist of nanoparticles, organic luminescent materials. In addition, the micro topography and the luminescent property of the patterned surface have been characterized by using Scanning Electron Microscope (SEM) and fluorescence microscope, respectively. Finally, the fluorescence of the patterned nanoparticles was observed. [ABSTRACT FROM AUTHOR]

Synthesis of uniform nanocrystalline anatase TiO2 by sol–gel method was investigated using different thermal analysis (DTA), thermogravimetric analysis (TGA), X-ray diffraction (XRD) and scanning electron microscope (SEM) techniques. Thermal treatment of the precursor at 350°C for 2 h in air results in the formation of nanocrystalline anatase TiO2 with the average crystal size of 21.5 nm. Quantitative analysis through energy dispersive X-ray spectroscopy (EDS) indicated that the atomic ratio of Ti:O ≈ 1:1 is close to the stoichiometric ratio of TiO2, leading to the evident fact that the prepared nanoparticles are indeed the TiO2 material. [ABSTRACT FROM AUTHOR]

ZnS nanofibers with lamellar mesostructure could be built up from in situ generated ZnS precursors via hydrothermal routes using neutral n-alkylamines as structure-directing template and ethylene diamine tetraacetic acid (EDTA) as stabilizer. The morphology and structure of the obtained products were thoroughly investigated via scanning electron microscope (SEM), energy dispersive analysis of X-rays (EDX), transmission electron microscope (TEM), X-ray powder diffraction (XRD) and thermal analyses. HRTEM and XRD results revealed that the so-produced nanofibers were lamellar mesostructure and its framework was built of crystalline wurtzite ZnS. It was also found that the distance between the layers was proportional to the chain length of the alkylamine. The UV-visible absorption spectrum showed that the nanofibers exhibited strong quantum-confined effect with a blue shift in the band gap. Finally, a probable mechanism for the assembly of the nanofibers was also proposed. [ABSTRACT FROM AUTHOR]

Micropatterned films are attractive materials with potentials applicable in the fields of photonics, electronics, biotechnology, and so on. Fabrication of honeycomb-patterned microporous films ("honeycomb films") by casting dilute solution of various types of polymers under high humidity has been already reported. Introduction of luminescent nanoparticles into micropores of the film is investigated to realize photofunctional materials. Novel luminescent monodisperse nanoparticles containing europium or terbium complexes have been prepared for this experiment. By a scanning electron microscope (SEM), many wrinkles were observed on the surface of lanthanide-containing nanoparticles. Zeta potential of the lanthanide-containing nanoparticles was positive. Composites of honeycomb film and the nanoparticles, the latter embedded in the micropores, were fabricated by dropping water dispersion of mixture of the europium-, terbium-, and no-dye-containing nanoparticles on the films. The number of the nanoparticles in a micropore was estimated no less than 400 by analyzing SEM images. The ratio of emission intensity of terbium to that of europium in the individual micropores of the composites fluctuated and deviated from the intensity ratio in bulk. Numerical simulation confirmed this tendency qualitatively. [ABSTRACT FROM AUTHOR]

The cadmium-doped SnO2 nanoparticles have been successfully prepared by a simple mechanochemical reaction and subsequent thermal treatment. The samples were characterized using X-ray diffraction (XRD), scanning electron microscope (SEM) and energy dispersive spectroscopy (EDS). Thermal treatment of the as-milled powder at 700°C for 2 h resulted in the formation of Cd-SnO2 nanoparticles with an average crystal size of 13 nm, varying with the calcination temperature. The effect of doped cadmium on the crystal size of the nanoparticles was investigated. The lattice parameter (c) of the Cd-SnO2 nanoparticles, lower than that of pure SnO2, decreased with increasing amount of doped cadmium. The apparent activation energy of Cd-SnO2 nanocrystal growth during calcination of the precursor was calculated to be 70.8 kJ/mol. The mechanochemical method is a novel, cheap and convenient technique especially suitable for large-scale synthesis of nanosized materials. [ABSTRACT FROM AUTHOR]

The nanoalumina particles were produced by the wire explosion process. The size and the shape of the particles were measured using Transmission Electron Microscope (TEM) studies. The Scanning Electron Microscope (SEM) studies were carried out to confirm that the particles are of sub-micron size. The compositions of the material were characterized through the Energy Dispersive Angle X-ray Analysis (EDAX) results. The Wide Angle X-ray Diffraction (WAXD) and the Fourier Transform Infra-Red (FTIR) results confirmed the nanosize powder formed by the process as crystalline γ-Al2O3 powder. The thermal characteristics were analyzed using Thermo-gravimetric Differential thermal analysis (TG-DTA). It is identified that the local temperature of the medium at the time of formation of nanopowder decides the phase characteristics of the powder material. The formation mechanism of nanopowder by wire explosion technique was explained in detail. The mechanism of nanopowder formation and the characteristic changes that occur during the explosion process were recorded using a high-speed digital camera. [ABSTRACT FROM AUTHOR]

This paper presents the investigations made on the effect of impact response of glass fiber-reinforced epoxy nanocomposites. The laminates are prepared using 6 layers of glass woven roving mates of 610 gsm and MMT clay content varied from 0%, 1%, 3% and 5%. The prepared composite laminates were subjected to low-velocity impact with energy of 18 J. The methodology used for the impact test is based on the ASTM D3029 standard. During these impact tests, load-time histories, Peak load and absorbed energy were recorded by load cell. The incorporation of 1% and 3% nanoclay lead to higher load bearing capacity and energy absorption. Damages produced on the front and back surfaces of the samples were analyzed by visual inspection methods and scanning electron microscope. [ABSTRACT FROM AUTHOR]