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• Sensing capability of PLA-nanofiber reinforced PCL composite-based smart porous scaffolds for online health monitoring. • Fused filament fabrication parameters for maximizing yield stress. • Simulated return loss , specific absorption ratio, and resonance frequency for PCL and PCL composites. In the past, studies were reported on polycaprolactone (PCL) and polylactic acid (PLA) nanofibers (NF)-based scaffolds for tissue engineering applications. But hitherto, little has been reported on the sensing capability of PLA-NF reinforced PCL composite (PPNC)-based smart porous scaffolds for online health monitoring (OHM) of joint strains/ tendon tears/ contusions/ rhabdomyolysis, etc. In this study, smart porous scaffolds (SPS) were fabricated by fused filament fabrication (FFF) using PPNC for OHM (of joint strains/ tendon tears/ contusions/ rhabdomyolysis, etc.) with tuneable sensing and mechanical properties. The results suggest that FFF parameters, zigzag fill pattern, 0.20 mm layer thickness, and 80 % infill percentage are the best-predicted settings for maximum yield stress (σ ymax) of SPS. Further, a vector network analyzer was used to ascertain the sensing capability of SPS. The resonance frequency (R f) for PCL (virgin) and PPNC with minimum yield stress (σ ymin) and σ ymax were observed as 2.3021, 2.6008, and 2.4315 GHz respectively. The simulated return loss (S 11) , specific absorption ratio (SAR), and R f for PCL (−10.7593 dB, 0.977 W/kg, and 2.6450 GHz), PPNC with σ ymin (−10.5737 dB, 1.437 W/kg and 2.3400 GHz) and PPNC with σ ymax (−10.9429 dB, 1.155 W/kg and 2.5050 GHz) indicate that experimental data is in good co-relation with the observed values. The results are supported by a scanning electron microscope and differential scanning calorimetry. [ABSTRACT FROM AUTHOR]

• Investigate the influence of Cu interlayer on of DB IN718/SS-304L interface. • Cu interlayer significantly reduced the formation of IMCs and carbides. • Joint strength of 143 MPa was achieved without Cu interlayer. • Joint strength was improved by 134% using Cu interlayer. • Microhardness was reduced by 17% with the Cu interlayer. Diffusion bonding (DB) of AISI 304L austenitic stainless steel (SS-304L) and Inconel 718 with and without Cu interlayer was performed at 950 °C for 90 min under vacuum of 8x10−2 MPa. The resulting mechanical, microstructural, and compositional analyses of the bonded interfaces were analyzed using lap shear and microhardness tests, optical and scanning electron microscopes (OM and SEM) equipped with energy-dispersive spectroscope (EDS) and X-ray diffraction (XRD). It was observed that the bonding interface without Cu interlayer was comprised of TiC, NbC, Mn 23 C 7 , Cr 23 C 6 , Cr 3 C 2 , μ-phase (Fe 2 Nb), NiTi 2 , and FeTi. However, these carbides and intermetallic compounds (IMCs) were eliminated with the insertion of the Cu interlayer. This enhanced the joint strength from 143 to 334 MPa and reduced the interfacial hardness by 17 %. [ABSTRACT FROM AUTHOR]

• YSZ and Ti6Al4V were successfully brazed using an N-Cu foam as the interlayer. • The shear strength of joints was improved by 83.1% when N-Cu foam was introduced. • The 3D structure and secondary phases could relieve the residual stress in the joint. This paper introduces a novel method to moderate the residual stress in a YSZ/Ti6Al4V alloy by using novel CuO nanostructure reinforced Cu foam (N-Cu foam) interlayer. The microstructure of the CuO nanostructure reinforced Cu foam interlayer and the achieved brazing joint is characterised via scanning electron microscope (SEM), X-ray diffraction (XRD) and transmission electron microscopy (TEM). It is found that nano-CuO structures can be successfully fabricated on the skeleton of the Cu foam and the 3D porous structure of which survives after the brazing process. The achieved brazing seam mainly consists of Ag solid solution (Ag(s,s)), Cu solid solution (Cu(s,s)) and fine Ti 3 Cu 3 O secondary phases, which is found to be beneficial to release the thermal stress. The strength of the joint achieved with an N-Cu foam interlayer is 95.6 MPa, which is 83.1% higher than the joints brazed without interlayers. [ABSTRACT FROM AUTHOR]

• SSG significantly affects the microstructural characteristics of EVA foam. • A unique two-phase structure forms on the cell wall of EVA/SSG foam. • The change of microstructure affects the deformation mode of the composite foam. In previous study, a novel composite foam that possesses cushioning properties is developed by incorporating shear stiffening gel (SSG) into Ethylene-vinyl (EVA) foam. In this work, uniaxial compression is used to obtain the mechanical properties of the proposed material under static loading. The test results demonstrate the additive SSG could effectively enhance the energy absorption capacity. With the aid of in-situ Scanning Electron Microscope (SEM), two characteristics, the homogeneous microstructural morphology and phase separation between SSG and EVA, are found that played dominant roles in the improvement of cushioning properties. [ABSTRACT FROM AUTHOR]

• Fluorine-free superhydrophobic coatings have been prepared successfully. • The superhydrophobic surface exhibits excellent abrasion resistance. • The superhydrophobic surface exhibits efficient oil-water separation ability. Superhydrophobic coatings have been prepared in this work by spraying toluene solution with different ratios of grafted epoxy resin and hydrophobic silica nanoparticles. Characterization by Fourier-transform infrared spectroscopy, scanning electron microscope, water contact angle techniques indicates that grafting with octadecylamine can effectively improve the hydrophobic property of epoxy resin with WCAs as high as 101.6 ± 3.1°, and that addition of SiO 2 nanoparticles makes the superhydrophobic coatings of SiO 2 /grafted epoxy resin feasible provided that the weight percentage of SiO 2 is over 35%. Moreover, the nanocomposite coatings exhibit good abrasion resistance as verified by the abrasion tests. Finally, the superhydrophobic coating is utilized to fabricate a superhydrophobic stainless-steel mesh on which the oil/water separation can be achieved with high efficiency and low cost. [ABSTRACT FROM AUTHOR]

Highlights • A facile template-free method was developed to synthesis hollow TiO 2 spheres. • The effects of etching reaction on morphology and structure of TiO 2 spheres were investigated. • The hollow TiO 2 spheres exhibited unique surface assembled with enriched nanothorns. • The hollow TiO 2 spheres showed excellent photocatalytic activity under visible light. Abstract The monodisperse hollow TiO 2 spheres (HTS) were fabricated by facile template-free route involving direct precipitation and etching reaction. Tetrabutyl titanate was used as titanium precursor to form amorphous TiO 2 spheres (ATS) directly in ethanol-acetonitrile mixed solution. Then, the ATS were etched by F− with the protection of PVP to form HTS under hydrothermal reaction conditions. The physical and chemical characterizations of synthesized samples were conducted by SEM, TEM, XRD and UV–vis diffuse reflectance spectroscopy. Result showed that morphology and structure of HTS can be easily controlled by adjusting time of etching reaction. The HTS obtained by etching for 4 h exhibited good hollow structure with unique shell assembled with enriched nanothorns, and it possessed good photocatalytic activity under visible light irradiation. [ABSTRACT FROM AUTHOR]

Graphical abstract Highlights • Grain boundary α did not always maintain a BOR with one of adjacent prior β grains. • Low-angle β/β boundaries can be passed through by α s plates. • Preferred α s plates may form at α p /β boundary with the similar orientation to the α p. Abstract Effect of boundary (β/β and α/β boundary) on the α phase precipitation in a near-α titanium alloy had been statistically investigated. The result shows that most grain boundary α (GBα) precipitates maintain a Burgers orientation relationship (BOR) with one of adjacent prior β grains. However, in some unique cases, the GBα did not maintain a BOR with either prior β grains due to preferential growth of equiaxed primary α (α p). It was also observed that the low-angle β/β boundaries can be passed through by secondary α (α s). Additionally, when an α p grain and an adjacent β grain have a near BOR, the preferred α s may form at α p /β boundary with the similar orientation to the α p due to low interfacial energy of low-angle α p /α s boundary. [ABSTRACT FROM AUTHOR]

Hierarchical SbPO 4 flower-like microspheres (SbPO 4 FM) have been successfully prepared by a facile solvothermal method. The XRD, TEM, SEM and BET techniques were adopted to inspect the obtained SbPO 4 products. Experimental results indicated that the as-prepared SbPO 4 flower-like microspheres belonged to a monoclinic phase and were assembled by numerous nanoplates to form hierarchical porous architectures. A self-assembly mechanism accounted for the formation of the as-prepared SbPO 4 flower-like microspheres. Besides, the electrochemical Li-storage property was also investigated as an anode for lithium-ion battery. [ABSTRACT FROM AUTHOR]

The present investigations are introducing for the first time a facile new trend of applying industrial ultrahigh energy CO 2 -laser (doubly sources) with output of 1650 W as an energetic activator for hydrothermal technique. Fe(II)-2,3,7,8,12,13,17,18-Octa-ethyl-porphyrinato-coordinated polymeric MOFs were selected as model for application and it was successfully synthesized via high-energy intensive laser assisted in nine minutes only. The laser assisted Fe(II)-MOFs were carefully characterized via X-ray diffraction (XRD), scanning electron microscope (SEM) and three dimensional atomic force microscope (3D-AFM). Furthermore BET specific surface area of Fe(II)-MOFs was evaluated and gave promising results of 2743 m 2 /g which is better than some of common iron-MOFs mentioned in literatures. [ABSTRACT FROM AUTHOR]

A novel filter paper (FP) with superhydrophobicity and superoleophilicity was prepared via adsorption and immersion process for the separation of surfactant-stabilized water-in-oil emulsions. The realization of superhydrophobicity with a water contact angle of 153° benefits from the Cu(OH) 2 nanostructure formed on FP and subsequent stearic acid (STA) modification. The three-dimensional network of FP as well as superhydrophobic and superoleophilic property can facilitate the demulsification of emulsified oil, thus the only gravity-driven separations of various water-in-oil emulsions with high oil flux and good recyclability have been achieved. The superhydrophobic FP can be massively applied in emulsion separation due to its facile preparation and superior performance. [ABSTRACT FROM AUTHOR]

The plastic deformation of biodegradable zinc alloy with 1 wt% of magnesium by hydrostatic extrusion (HE) was performed. The influence of severe plastic deformation on the microstructure and mechanical properties of ZnMg was investigated. Cumulative extrusion with total true strain ε = 3.33 was applied to the homogenised material. Microstructure observations carried out using scanning electron microscope (SEM)/ Electron Backscatter Diffraction (EBSD) methods, as well as static tensile tests, revealed outstanding results. After the deformation, grain refinement causing substantial strengthening of the material was observed. An average grain size equal to 700 nm and YS = 316 MPa, UTS = 435 MPa with ε f = 35% was obtained. These results indicate that the HE method enables the grain refinement level and mechanical properties of ZnMg to be obtained, which would not be possible with conventional methods of plastic deformation. The properties of the Zn alloy after HE satisfy the requirements for bioresorbable stent applications. [ABSTRACT FROM AUTHOR]

• Weaking mechanism of electron beam weld Mo alloy was revealed. • Absence of La 2 O 3 phase promoted the softening of the joint. • MoO 2 phase and high residual stress resulted in weakening of the joint. Electron beam welding of La 2 O 3 dispersion strengthened molybdenum alloy is carried out in this experiment. Optical microscopy (OM) and scanning electron microscope (SEM) were used to study the microstructure of the joint. Microhardness tests and tensile tests were conducted to evaluate the mechanical properties of the joint. Results show that coarse columnar grains are generated in the weld owing to the absence of the La 2 O 3 strengthening phase. The joint is softened with a mean hardness of 200 HV, lower than 250HV of the base metal. Micro cracks in some grain boundary regions are detected with MoO 2 phase. High residual stress is accumulated in the weld region. Both the generation of the MoO 2 phase and the high stress promotes the weakening of the joint. The strength of the joint is only 54 MPa. [ABSTRACT FROM AUTHOR]

• WC-Co-TiC and 304 stainless steel (SS) for the micro drill were prepared. • The external material is WC-Co-TiC with uniformity and stability. • The internal material is 304 stainless steel with high accuracy under a small size. • The sintering temperature greatly affects WC-Co-TiC/304SS composite. In this study, the composites of the micro drill with nano WC powder, Co powder, TiC powder (WC:Co:TiC = 6:2:2) as outer material and 304 stainless steel as core are compressed at room temperature and sintered at high temperature in a vacuum tube furnace by self-designed mold in the laboratory. The influence of sintering temperature on microstructure, diffusion of elements, hardness and wear resistance are studied by scanning electron microscope, hardness tester, and friction and wear tester. The results show that with the increase of sintering temperature, the number of micropores in WC-Co-TiC/304 stainless steel composites decreases, the mutual diffusion trend of Co and Ni increases, the Fe, Cr and W are slightly diffused, and Ti element has no obvious diffusion. With the increase of sintering temperature, the hardness increases and the wear resistance decreases of WC-Co-TiC/304 stainless steel composites. When the sintering temperature is 1310 °C, the hardness of WC-Co-TiC cemented carbide reaches the maximum value of 1394 HV, and the wear trace morphology is the smallest. The maximum depth of the wear trace is about 6841.2 Å, and the corresponding width is about 191.26 μm. Meanwhile, the lowest wear rate is 3.53 × 10-5 mm3 N−1 m−1. [ABSTRACT FROM AUTHOR]

• Insights into the properties of experimentally derived HAp was conducted using DFT. • XRD signatures and constrained lattice parameters reflect anomalies in properties. • Young's modulus and hardness of the BC 25/75 sample was higher comparatively. In the present study, the sol–gel route assisted with heat treatment was used to synthesize a novel mixture of hydroxyapatite (HAp) powders, and a computational study via first principle atomistic simulations was utilized to understand the structural properties of the compounds. To reveal the morphological features and nano-mechanical properties of the powders and pellets, respectively, a scanning electron microscope was used for samples imaging, while nano-indentation was conducted using grid nano-indentation arrays. Data from ab-initio calculations were close to experimental data obtained through X-ray diffraction studies, while a gradient in the particle shapes and sizes were evident from the microstructures. The BC 25/75 sample showed enhanced mechanical properties comparatively. [ABSTRACT FROM AUTHOR]

Core-shell structured mesoporous silica spheres were successfully fabricated by utilizing cetyltrimethyl ammonium bromide (CTAB) and protic ionic liquid (butylamine acetate) as the co-templates. The obtained samples were characterized by N 2 gas sorption, scanning electron microscope (SEM) and transmission electron microscopy (TEM). The results established that silica spheres possessed smaller pores in the shell and larger mesopores in the core. The formation mechanism of the silica sphere which is based on the interaction between protic ionic liquid (PIL) and CTAB is tentatively elucidated. And it is valuable to develop this facile route and the mesoporous silica spheres can be beneficial for a wide range of applications. [ABSTRACT FROM AUTHOR]

CoMn 2 O 4 microflower and microsphere structures have been facilely and solvothermally realized by adjusting the urea concentration. The morphologies of as-prepared CoMn 2 O 4 samples were investigated using field emission scanning electron microscope (FESEM). The chemical compositional and crystalline structural changes of as-prepared samples were characterized using X-ray diffraction (XRD) and thermogravimetric analysis (TGA). The present work has demonstrated that the urea concentration has played an important role in formation of CoMn 2 O 4 microflower and microsphere. The mechanism of the morphology-controlled synthesis of CoMn 2 O 4 is also discussed. [ABSTRACT FROM AUTHOR]

Cactus-like NiO was successfully synthesized by adjusting reaction time of a simple hydrothermal approach. The different morphologies of the NiO samples obtained by different reaction time were characterized by X-ray diffraction (XRD), scanning electron microscope (SEM), transmission electron microscopy (TEM). And the gas-sensing performance of these products was studied, too. The results indicated that the sensor based on the cactus-like NiO nanostructures obtained by choosing appropriate reaction time showed much better sensing properties than other samples. The response of the sensor based on cactus-like NiO was about 13.51–100 ppm acetone at a working temperature of 260 °C, and the response and recovery time was 24 and 39 s, respectively. The improvement gas sensing properties based on cactus-like NiO sensor may be due to the unique structures, the good crystallization and large surface area. [ABSTRACT FROM AUTHOR]

Porous WS 2 films have been deposited on ridge-like Ni coated Cu foils using a magnetron sputtering system, their morphology and structure were characterized by field-emission scanning electron microscope, high-resolution transmission electron microscopy and micro-Raman spectrometer. Electrochemical evaluation showed that, as negative electrode for lithium-ion batteries, the representative ridge-like Ni supported WS 2 film electrode performs a high reversible capacity and excellent rate capability which can deliver a discharge capacity as high as 1180 mA h g −1 after 100 cycles at 100 mA g −1 . The capacities almost remain the same as the current density increases from 100 to 800 mA g −1 . Even at 1600 mA g −1 , the electrode can deliver a capacity as high as 986 mA h g −1 . [ABSTRACT FROM AUTHOR]

Al fiber-reinforced cordierite was prepared by solid state reaction of clay, talc and alumina sintered at 1370 °C in carbon embedded condition. The microstructures were observed via scanning electron microscope (SEM), three-point flexural strength was examined on a universal testing machine. The SEM microphotograph shows a weak-bonded interfacial phase AlN, which was attributed to the reaction between Al and N 2 at high temperature in carbon protection condition, was formed between cordierite matrix and Al fiber. It facilitates fiber debonding and fiber pullout during fracture test. Three-point flexural test indicates both fracture displacement and flexural strength of Al-reinforced cordierite are bigger than that of the monolithic cordierite. With increasing Al-fiber addition, the higher strength and longer displacement were found. [ABSTRACT FROM AUTHOR]

After a standard heat treatment, the morphological evolution of γ′ precipitates in the directionally solidified Ni-base superalloy M4706 with time is investigated during thermal exposure at 800 °C. In contrast to previous results, it is found that as the average particle size increases from 241 to 368 nm with increasing aging time up to 10,000 h, the shape of γ′ precipitates gradually changes from cuboidal to sphere-like. X-ray diffraction experiments reveal that the constrained γ/γ′ lattice misfits of M4706 fall into the range of −0.226% to −0.223% between 800 and 850 °C, whereas the value is −0.529% at 1050 °C. Based on the experimental results, the morphological transition of γ′ precipitates is discussed. [ABSTRACT FROM AUTHOR]

Influence of surface nanocrystal on the interface reaction between Fe 3 Al and 1060Al alloy is investigated. A nanocrystal layer serving as interlayer was produced on Fe 3 Al by surface mechanical attrition. Then Fe 3 Al was diffusion bonded with 1060Al alloy at 873 K. Surface microstructure of Fe 3 Al alloy after mechanical attrition is observed on X-ray diffractometer and transmission electron microscope. Atom diffusion and phase constitution at the diffusion interface is observed on scanning electron microscope and energy disperse spectroscope. Results show nanocrystal about 37 nm in size is produced on Fe 3 Al alloy after 10 min attrition. Microstructure and phase constitution at diffusion interface imply that atom diffusion is restrained at 873 K because of the presence of nanocrystal. [ABSTRACT FROM AUTHOR]

This letter focuses on the capability of Transmission Kikuchi Diffraction (TKD) in Scanning Electron Microscope (SEM) for obtaining microstructural and micro-textural information from nano-grained oxide scales formed on a FeCrAl alloy. Orientation maps, with an indexing rate of 85%, showed the formation of grains in the range 20–300 nm. TKD revealed the existence of an orientation relationship at the alloy/oxide interface as well as the presence of a single grain (40 nm) with spinel structure in the alumina scale. A pre-tilted sample holder was designed for TKD investigations at short working distances with minimized mechanical drift of the thin foils. [ABSTRACT FROM AUTHOR]

The white magnetic paper is a kind of promising functional materials in many fields. In this paper, a new high white magnetic paper had been successfully prepared by lumen loading process using Tb-based inorganic magnetic particles. The samples were characterized by superconductivity quantum interference device (SQUID), scanning electron microscope (SEM) and physical properties. The effect of the addition of magnetic particles on the physical properties of magnetic paper was investigated in detail. SEM micrograph clearly shown that the magnetic particles had attached evenly in the interstitial of fibers and lumen loading allowed magnetic particles to be introduced into the lumens of wood fibers. And SQUID indicated that the magnetic particles and papers were paramagnetic materials. The results of physical properties of magnetic papers indicated that the tensile strength and tearing strength of papers increased firstly and then decreased with increasing addition of magnetic particles. Meanwhile, the whiteness of papers was improved obviously which was greater than 80% in contrast to other papers produced by adding ferrite. [ABSTRACT FROM AUTHOR]

• Inconel625-HSLA steel functionally graded materials were fabricated. • Laves phases precipitation was effectively suppressed by electromagnetic stirring. • Primary dendrite spacing of the functionally graded materials was reduced by 22.6% • Tensile strength along with building direction was improve from 512 MPa to 563 MPa. Inconel625- high strength low alloy (HSLA) steel functionally graded material (FGM) specimens have been fabricated by wire arc additive manufacturing (WAAM) system with synchronous electromagnetic stirring (EMS). The chemical composition distribution has been analyzed to prove the graded transition of the FGMs. Scanning electron microscope (SEM), energy dispersive spectroscopy (EDS) and transmission electron microscope (TEM) were applied to analyze the microstructures of the FGMs. By using EMS, the primary dendrite spacing of FGM is reduced by 22.6%, the size of Laves phases in the FGM has been decreased with from about 2 μm to less than 100 nm, and the tensile strength along with building direction has been improved from 512 MPa to 563 MPa. [ABSTRACT FROM AUTHOR]

[Display omitted] • Graded NiCoW coating was synthesized by one step, galvanostatic, DC electrodeposition. • Graded NiCoW coatings possess composition and structure varying crossing thickness. • Induced co-deposition mechanism of graded NiCoW coatings has been elucidated. In this paper, a novel method for synthesis of functionally graded alloy coatings by using induced co-deposition has been proposed. The graded NiCoW alloy coatings were synthesized by one step, galvanostatic, direct current electrodeposition from a sulphate-citrate electrolyte. Scanning electron microscope, energy dispersive spectroscopy and X-ray diffractometer were applied to characterize the as-deposited coatings, which possess the composition and structure gradually varying crossing the coating thickness. During the electrodeposition, the competition between the formation of Ni complexes and Co complexes as well as the competition between induced deposition of W and direct deposition of Ni, are responsible for the formation of graded NiCoW coatings. This easy synthesis method by using induced electrodeposition should be a promising route for the preparation of functionally graded alloy materials. [ABSTRACT FROM AUTHOR]

Bismuth-based microrods (BiMRs) were synthesized through a single reductant-controlled chemical reduction method. With the various quantity of reductant, different morphologies of Bi based materials were obtained. Characters of BiMRs were investigated by using scanning electron microscope (SEM), X-ray diffraction (XRD) and X-ray photoelectron spectroscopy (XPS). The results showed that the product was uniform rods with a smooth surface and neat edges. Furthermore, BiMRs was consisted of bismuth and bismuth oxide which made the material possess both advantages of metal and metal oxide. BiMRs had shown excellent electrochemical performance and was successfully used for the determination of total dissolved iron in real water samples. Considering their environmentally friendly and excellent electrochemical performance, BiMRs might be used as a promising electrode material in electroanalysis field. [ABSTRACT FROM AUTHOR]

In this investigation, we report the formation of new 3-D aggregates consisting of Ag-Au nanoparticles obtained in aqueous solution by a facile method using Aloysia triphylla plant extract as a reducing and stabilizing agent. SEM and EDS analysis reveal that the dimensions of 3-D arrays are estimated to be about 2.5 µm wide, 0.5 µm thick, and 2 µm long. The 3-D geometric aggregates have strong microstructures that are similar to those of ordinary crystalline materials. The microstructures are close-packed with straight edges and facets but do not have grain boundaries. HRTEM images indicate that the 3-D arrays are a consequence of the nanoparticles aggregation inside an organic matrix and the presence of Au forming the BNPs. [ABSTRACT FROM AUTHOR]

Abstract: In this study, macroscopic polyamide 66 (PA66) nanofiber bundles were successfully electrospun using two electrode pins as collector. One of the pins can rotate with a speed of 300rpm. Scanning electron microscope, tensile test, wide-angle X-ray diffraction and differential scanning calorimetry were employed to characterize the arrangement of electrospun nanofibers in bundle, tensile property and microstructure of electrospun nanofiber bundles. Results show that the collector pin׳s rotating speed not only significantly influences the arrangement of nanofibers in bundle but also the crystallinity and porosity of nanofiber bundles, which further influence the tensile strength and failure strain of nanofiber bundles. [Copyright &y& Elsevier]

Abstract: ZnO nanotetrapods have been large-scale prepared through a facile and ultrafast induction-heating method. The morphologies of ZnO nanostructures can be adjusted by modifying the induction-heating supply power. The ZnO products are characterized by X-ray diffraction, scanning electron microscope, transmission electron microscope and selected area electron diffraction. The results reveal the presence of octahedral structured nucleus in the center of tetrapods with wurtzite phase branches. The possible formation mechanism for these ZnO nanostructures is proposed. [Copyright &y& Elsevier]

Abstract: Large sized sphere—like polyhedrons of Cr2O3 were prepared via hydrothermal synthesis under the assistance of the surfactant cetyltrimethylammonium bromide (CTAB). The Starting materials were K2Cr2O7 and HCHO. When the amount of CTAB changed from 0.15 to 0.01g and the amount of K2Cr2O7 kept 3.5g, morphologies of products changed in sequence. And 0.05g CTAB corresponded to the 38–72µm sphere -like polyhedrons of Cr2O3. The amount of K2Cr2O7 also led to obvious changes of morphologies. The above experimental phenomena are assigned to influences of amounts of the added surfactant and reactant on the nucleation and diffusion rate, which lead to different morphologies of products. Phase purity and composition of precursor and products were investigated by X-ray techniques (XRD), and microstructures were observed by field emission scanning electron microscope (SEM) [Copyright &y& Elsevier]

[Display omitted] • The corrosion behavior of 15CrMn steel in SCSA solution was studied by immersion test and electrochemical methods. • The corrosion product mainly comprised of Fe 2 O 3 , Fe 3 O 4 , and FeNaS 2. • The thickness of corrosion product film increased with time. • Polarization curve described the corrosion products of 15CrMn steel has the wide passivation section. The corrosion behavior of 15CrMn steel in S2−-containing sodium aluminate (SCSA) solution was studied by immersion test and electrochemical methods. The phase analysis and cross-section corrosion products were performed using scanning electron microscope (SEM) and X-ray diffraction (XRD). Results showed a layer of Fe 2 O 3 , Fe 3 O 4 , and FeNaS 2 corrosion product film on the surface of 15CrMn steel after corrosion. The film improved the protective effect on the sample, which led to the decrease of polarization current and the increase of Nyquist's arc radius at 4 days. As the corrosion time extends to 5 days, the corrosion product layer loosened and partly fell off due to the formation of unstable sulfide on the substrate surface, promoting a new corrosion process. [ABSTRACT FROM AUTHOR]

• The preparation of antibacterial synthetic non-woven materials is established. • Gas-discharge plasma of low-pressure radio-frequency discharge is used for this goal. • The polypropylene textile materials were treated with silver nanoparticles. • To study the antibacterial activity, colony formation of E. Coli culture was used. The presented work is devoted to the study of the use of a gas-discharge plasma of a low-pressure radio-frequency discharge in the processes of preparing substrates and fixing silver nanoparticles in the preparation of antibacterial synthetic non-woven materials for disposable use. The results of the study of antibacterial activity to assess the inhibition of colony formation of E. coli culture on polypropylene non-woven materials for disposable surgical, medical clothing and underwear, as well as personal protective equipment are presented. To assess the antibacterial activity, fluorescent staining of the samples was carried out. The study of the surface of the samples was carried out using a scanning electron microscope. The materials were treated with preparations based on silver nanoparticles; to ensure the uniformity of properties and fixation of the preparations, treatment in radio-frequency gas-discharge plasma was used. The use of radio-frequency gas-discharge plasma treatment in the processes of modification of polypropylene fibers with antibacterial preparations based on silver nanoparticles makes it possible to obtain antibacterial materials with bacteriostatic and/or antibacterial activity over their entire surface area. [ABSTRACT FROM AUTHOR]

• CdTe thin films were grown via close-spaced sublimation in vacuum (pure Ar ambient) and Ar/O 2 ambient. • CdTe thin films demonstrated cubic zinc blend structure and crystallite size was in the range of 25–45 nm. • O 2 presence had a substantial effect in grain size growth up to 7.19 µm. • Carrier concentration increased slightly with the rise in O 2 concentration. • CdTe thin films deposited in (10% O 2 + 90% Ar) ambient might be favourable as the optimum absorber layer. In this work, cadmium telluride (CdTe) thin film was deposited in vacuum (pure argon ambient) as well as different argon (Ar) and oxygen (O 2) ambient conditions using close-spaced sublimation (CSS) method at the deposition pressure of 1 Torr. The deposited films were characterized via X-ray Diffraction (XRD), Scanning Electron Microscope (SEM), UV–Vis spectrophotometer and Hall Effect measurement for the analysis of structural properties, morphology, optical properties and electrical properties, respectively. XRD patterns exhibited almost similar preferential orientation plane at (1 1 1) irrespective of the O 2 concentration. SEM surface morphology microstructure revealed that O 2 presence had a substantial effect on grain size reaching up to 7.19 µm. Optical properties also demonstrated insignificant changes in the direct band gap values of around 1.48 eV. Carrier concentration showed an upward trend in the order of 1013 cm−3, whereby resistivity and mobility did not change substantially either in vacuum (pure Ar ambient) or in Ar/O 2 ambient. [ABSTRACT FROM AUTHOR]

Abstract: Ag/AgBr is a highly efficient visible-light plasmonic photocatalyst but suffers from severe aggregation of the particles. To settle this problem, we simply added a small amounts of graphene oxide (GO) to the Ag/AgBr reaction system. Expectedly, well monodispersed Ag/AgBr particles bonded on the rGO sheets (Ag/AgBr/rGO) was obtained, as observed by SEM. The adsorptive and photocatalytic activities of the as-prepared samples were investigated by degradation of RhB under visible light irradiation. Compared with pure Ag/AgBr, Ag/AgBr/rGO nanocomposite shows enhanced performance in both the adsorptive and photocatalytic activities. [Copyright &y& Elsevier]

Abstract: This study describes the preparation of hydroxyapatite microspheres for local delivery of alendronate and BMP-2. The hydroxyapatite microsphere preparation was initiated by enzymatic decomposition of urea and accomplished using an emulsification process (water-in-oil) for nucleation and growth of hydroxyapatite within the microemulsion. The microspheres obtained were then sintered at 500°C. Scanning electron microscope (SEM) indicated that the microspheres have particle-in-sphere morphology, so called ‘microstructured microspheres’. The viability of L-929 cells in the presence of sintered microspheres was 85%. The adsorption efficiencies for alendronate varied from 27.2% to 84.1% depending on the loading conditions. For BMP-2 loading, 79.2% was absorbed on the microspheres when a BMP-2 concentration of 25μg/ml was used. [Copyright &y& Elsevier]

Abstract: LiFePO4/C composite microspheres have been synthesized as lithium-ion battery cathode material with good high-rate capability and cycling stability. In the precursor, polyvinyl alcohol (PVA) gel was chosen as carbon source for its excellent film-forming properties in spray drying process. Both TEM and SEM results indicated that the carbon layers transformed from PVA gel films were well coated around LiFePO4 units in the composite microspheres. This unique LiFePO4/C composite microspheres exhibited excellent high-rate capability and cycling stability, with discharge capacities reaching up to 150 and 100mAhg−1 at 0.1C and 10C current rates, respectively. [Copyright &y& Elsevier]

Abstract: The microstructure of high manganese steel solidified under 6GPa was examined by using OM, FEGSEM and TEM for analysis of influences of high pressure on phase transformation and the morphology of carbides. The results indicate that the microstructure consisting of complete equiaxed dendrites, the mean dendrite arm spacing of which was ~18μm, was remarkably refined under 6GPa. The change of the morphology of carbides from needle-like and rhombic carbide (M3C) to nodulized cubic carbide (M23C6) was observed by TEM, which is associated with the undercooling and distribution of trace elements of manganese. The diameter of spheroidal carbides is approximately between 150nm and 200nm. [Copyright &y& Elsevier]

Abstract: Microwave absorbing material PPy/Ag/NanoG was prepared by in situ polymerization of Pyrrole on the surface of silver-coated conductive graphite nanosheet (Ag/NanoG). The morphologies and nanostructures of PPy, Ag/NanoG and PPy/Ag/NanoG were characterized by scanning electron microscope (SEM), energy dispersive spectroscopy analysis (EDS) and X-ray diffraction analysis (XRD) respectively. Results show that Ag/NanoG has layered structure with high aspect ratio (width-to-thickness) and most of Ag/NanoG nanoparticles are encapsulated by PPy. Measurement of electromagnetic parameters shows that the complex permittivity (ε*=ε′–jε″), complex permeability (μ*=μ′–jμ″), dielectric loss tanδe =ε″/ε′ and magnetic loss tanδm =μ″/μ′ of PPy/Ag/NanoG are superior to those of PPy. The reflection loss of PPy/Ag/NanoG is below −15dB at the X band from 8.2 GHz to 12.4 GHz and the minimum loss value is −18.21dB at 9.86GHz. [Copyright &y& Elsevier]

Abstract: A simple low temperature hydrothermal process was employed to fabricate the needle-like ZnO array in the diluted butyl amine. The microstructure, morphology and the photoluminescence property of the as-prepared products were characterized by x-ray diffraction (XRD), transmission electron microscope (TEM), field emission environment scanning electron microscope (SEM) and photoluminescence spectrum (PL). The results show that the needle-like ZnO crystals are hexagonal wurtzite monocrystal with slender figure and smooth surface. A possible growth mechanism of the needle-like ZnO array related to the diluted butyl amine is proposed. The PL spectrum of the needle-like ZnO array shows a strong blue light emission at 437nm and a relatively low ultraviolet emission at 377nm. [Copyright &y& Elsevier]

Abstract: Aluminum–silicon (Al–Si) casting alloys are the most frequently used alloys in the automotive industry. The modification of its microstructure is an important practice for refining the large needles of the eutectic silicon into fine fibrous or lamellar particles. In this study, the chemical and microstructural analyses of the samples taken during the submerged SrO powders injection tests in magnesium (Mg)-containing molten Al–Si alloys demonstrated the feasibility of Sr uptake in the bath, as SrO is reduced through metallothermic reactions in the molten alloys, producing a suitable silicon eutectic modification effect. The parameters that were evaluated during the experiments included temperature of the molten bath, size of SrO powders, initial Mg concentration in the molten alloy, and injection time. Based on the characterization of the reaction products of partially reacted SrO particles using the scanning electron microscope (SEM) as well as the X-ray diffraction (XRD) analysis of the samples of dross obtained during the injection tests, the sequence of the reaction was proposed. It was observed that the initial Mg content is a key parameter in accelerating the reaction rate through chemical reactions that produce MgAl2O4 as the main reaction product. [Copyright &y& Elsevier]

• The fatigue behavior of AA2014 alloy is investigated. • The fracture features of different regions were examined under Scanning electron Microscope. • The fatigue behavior of each sample is correlated with microstructural features. The present investigation studies the actual fatigue crack growth behavior of AA2014 alloy processed using multi-pass overlapping friction stir processing. The results revealed that friction stir processed samples sustained a large number of fatigue cycles than base metal due to the various microstructural aspects in the processed zone. The fractured surface of fatigue samples revealed the presence of ridges and plateaus in the Stage-I crack propagation region and dimples and striations in the Stage-II crack propagation region. [ABSTRACT FROM AUTHOR]

Abstract: Ball-nanostructured MnO2/MWCNTs composite was successfully prepared by microwave irradiation. The surface morphology and structures of the composite were examined by scanning electron microscope and X-ray diffraction. Multi-walled carbon nanotubes play a role as sustainment to inhibit MnO2 nanoplates from collapsing into nanorods. The electrochemical studies indicated that the composite had ideal capacitive performance and high specific capacitances of 298 F g−1, 213 F g−1 and 198 F g−1 at the current density of 2 mA·cm−2, 10 mA·cm−2 and 20 mA·cm−2, respectively. The formation mechanism of nanostructured MnO2/MWCNTs and the electrochemical behaviour of composites were discussed in detail. [Copyright &y& Elsevier]

Abstract: Copper deposits with smooth surface were prepared on a cylindrical cathode by a simultaneous electroforming and polishing process. In a specifically developed equipment, the cathode was embedded in insulating ceramic beads, and the beads were forced to polish the deposit surface during electrodepositing. The prepared deposits were characterized by scanning electron microscope (SEM) and transmission electron microscope (TEM). It was found that simultaneous polishing in electrodeposition could evidently affect the microstructure of the deposits and smooth their surfaces. In contrast with the deposits electrodeposited by traditional method, the ones produced by the new process present higher microhardness and better corrosion resistance in neutral aqueous NaCl solution. Their structure and properties depend on the strength of the polishing effect, which can be enhanced by increasing the cathode rotational speed. [Copyright &y& Elsevier]

Abstract: The hydration process of K-PSS geopolymeric cement was in situ quantitatively investigated by environment scanning electron microscope (ESEM) under 80% relative humidity. An energy dispersion X-ray analysis (EDXA) was also employed to determine the chemical composition of the hydration product. The ESEM micrographs showed that metakaolin particles pack loosely at 10 min after an initial mixing, resulting in an existence of many large voids. As the hydration proceeded, some gels were produced and gradually precipitated on the surfaces of these particles. At a later stage, these particles were covered by thick gel layers, and their interspaces among the metakaolin particles were also completely filled up. The corresponding EDXA results illustrated that the molar ratios of K/Al and Si/Al decreased with the development of hydration. The molar ratios of K/Al and Si/Al of the hydration products at an age of 13 h amounted to 1.06 and 2.14 respectively, which were very close to the theoretical values (K/Al=1.0, Si/Al=2.0) for K-PSS geopolymeric cement hardened paste. In addition, well-developed crystals could not be found at any ages, instead sponge-like amorphous gels have always been observed during the whole hydration process. [Copyright &y& Elsevier]

Abstract: The SiC fibers, ropes and columnar-like fibers have been synthesized on the substrate of Co-based DSX40M alloy by electron beam (EB) melting. The fibers have been prepared from the SiC particles under high vacuum. The microstructure of the SiC fibers, ropes and columnar-like fibers has been investigated by scanning electron microscope (SEM) having energy dispersive spectroscopy (EDS) as an attachment. The coating of Co, Cr and Ni is observed on the surface of the SiC fibers, ropes and columnar-like fibers. A slight charging is observed in the case of the ropes while the columnar-like fibers and small size woven fibers did not show this effect suggesting the semiconducting nature of the ropes. [Copyright &y& Elsevier]

Abstract: Gas tunnel type plasma spraying deposition has been applied successfully to the deposition of the SiC films on stainless-steel substrates. The microstructure and the surface morphology of the SiC films were characterized by means of X-ray diffraction (XRD) and scanning electron microscope (SEM). The control of the processing parameters such as powder feeding rate, composition of plasma working gases, spraying distance, and carrier gas flow rate allowed the deposition of dense, uniform, continuous, and high purity crystalline SiC films. The thickness of the SiC films varied from 3 to 10 μm. EDS analysis confirmed the presence of SiO2 in the deposited SiC films. [Copyright &y& Elsevier]

Abstract: The tracks of cathode spots produced after arcing on the surfaces of nanostructured W alloys were investigated using a scanning electron microscope (SEM). For nanostructured W–2%ThO2 cathodes, the distribution of cathode spots was dispersed and their geometrical properties were completely controlled by the shape and size of ThO2. For nanostructured W–20%Cu cathodes, the spots were also separated on Cu-rich phase. The results showed that cathode spots on the surface of nanostructured W alloys were quite different from those on the surface of commercial W alloys with coarse grain size, and the microstructure of the cathode materials had significant influence on the cathode spots propagation. Also, space-charge regions induced by internal electric field at the interface which responded to the effect of microstructure on cathode spots were suggested. [Copyright &y& Elsevier]

Abstract: In this paper, a novel α-FeSi2 nanobars material and structure, which may be used in nanoelectronic and microelectronic fields, were fabricated on (001) silicon wafers and the growth mechanism was discussed. The scanning electron microscope morphology indicates that the α-FeSi2 nanobars align along <110> directions on (001) silicon substrate, with the length up to 10 μm, width ranging between 20 and 200 nm, thickness about 10–100 nm, and triangle or trapezoids cross section. It seems that the optimal matching directions, the reconstruction in high temperature, and the interaction of original depositional iron nanoparticles by the magnetization of microwave magnetic field are the three factors that caused the formation and orientation of iron silicide nanobars. [Copyright &y& Elsevier]

Abstract: Effects of Pr6O11 doping on the microstructures and the electrical properties of Bi4Ti3O12 (BIT) were investigated using dense ceramics, which were prepared by a conventional ceramic technique. For all the samples, X-ray diffraction (XRD) analyses revealed Bi-layered perovskite structures, and the scanning electron microscope (SEM) micrographs showed well developed plate-like morphologies with random orientations. The P–E hysteresis loop of samples measured at room temperature exhibited a large remnant polarization and a low coercive field. In addition, the DC current–voltage properties measured at different temperature from RT to 550 °C were discussed. Results indicate that Pr6O11 can be a good additive to improve the properties of Bi4Ti3O12. [Copyright &y& Elsevier]

[Display omitted] • An amorphous Co 60 Fe 18 Ta 8 B 14 powdered alloy was prepared by mechanical alloying process. • Microstructural characterization of mechanically alloyed material using XRD and SEM was obtained. • Thermal stability was achieved using DSC analysis. • The amorphous alloy exhibits a wide supercooled liquid region of 83 K. • The crystallization occurs by three successive exothermic reactions. An amorphous Co 60 Fe 18 Ta 8 B 14 powdered alloy was prepared by mechanical alloying process. The XRD results confirmed that the amorphous phase becomes a dominant phase above 50 h milling. Observation by scanning electron microscope shows a succession of phenomena of severe plastic deformation, cold welding and fracturing of powder particles. This new amorphous alloy exhibits a wide supercooled liquid region of 83 K and its crystallization occurs by three successive exothermic reactions. [ABSTRACT FROM AUTHOR]