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Magnetite nanoparticles (Fe3O4) were prepared by chemical coprecipitation method using ferric chloride (FeCl3) and heptahydrate ferrous sulfate (FeSO4·7H2O) salts employing sodium hydroxide (NaOH) as a precipitant. To determine the size, shape, and chemical makeup of the produced magnetite nanoparticles, the generated powders were examined by transmission electron microscope, scanning electron microscope, atomic force microscope, and X-ray diffractometer. It was found that the magnetite powder had made a face-centered cubic crystal structure and spherical-like particle form with particle diameters of about 30 nm. The magnetic properties of magnetite nanoparticles were evaluated using a vibrating sample magnetometer. The obtained superparamagnetic properties of the produced nanoparticles, with saturation magnetization and coercivity of 50.75 emu/g and 30.09 Oe, respectively, allow them for applications in drug delivery, MRI contrast agent, catalysis, degradation of antibiotics, antibacterial activity, removal of heavy metals and organic dyes, etc. [ABSTRACT FROM AUTHOR]

Due to its outstanding physical, chemical, and thermal properties, an increasing consideration has been paid to produce copper (Cu) nanoparticles (NPs). Various methods are accessible for producing Cu NPs by conceiving the top–down and bottom–up approaches. Electrodeposition is a bottom–up method to synthesize high-quality Cu NPs at a low cost. The attributes of Cu NPs rely on their way of deduction and electrochemical process parameters. This work aims to deduce the mean size of Cu NPs. Artificial neural networks (ANN) and nature-inspired algorithms, namely genetic algorithm (GA), firefly algorithm (FA), and cuckoo search (CS) algorithm were used to predict and optimize the electrochemical parameters. The results obtained from ANN prediction agreed with data from the electrodeposition process. All nature-inspired algorithms reveal similar operating conditions as optimal parameters. The minimum NP size of 20 nm was obtained for the process parameters of 4 g·l−1 of CuSO4 concentration, electrode distance of 3 cm, and a potential difference of 27 V. The synthesized NP size was in line with the anticipated NP size. The scanning electron microscope and X-ray diffractometer (XRD) were performed to analyze the nanoparticle size and morphology. [ABSTRACT FROM AUTHOR]

Magnesium-based alloys were more prevalent in automobile applications owing to their mechanical properties, low mass, and density. However, its poor mechanical properties are restricting its applications. Therefore, the present study focuses on improving the mechanical properties of AZ31D alloy by reinforcing silicon carbide (SiC) and graphite (Gr) nanoparticles with weight fractions of 2%, 4%, and 6% using stir-casting technique. The microstructure analysis was performed using a scanning electron microscope. The elemental analysis was confirmed using energy-dispersive spectroscopy, and X-ray diffraction was used to study various phases in the nanocomposites. Further, the mechanical properties, such as microhardness, ultimate tensile strength, yield strength, and compression strength of the nanocomposites, were significantly improved by 53%, 59%, 62%, and 82%, respectively, as compared with base alloy. [ABSTRACT FROM AUTHOR]

The intention of this research is to recapitulate the two different fillers like E glass fiber and nanocarbon fiber, which were utilized to fabricate the polymer matrix composites by the assistance of epoxy resin. The mechanical compression molding was influenced to produce the polymer-based nanocomposites under consideration of optimal process parameters. There are three different weight fractions E glass fiber (40%, 45%, and 50%), nanocarbon fiber (10%, 15%, and 20%), and epoxy concentrations (30%, 40%, and 50%), respectively, that were used to produce the polymer matrix composites. Those processing parameters were designed by the L9 Taguchi with DOE technique to conduct the mechanical tests like tensile strength and hardness properties. The signal-to-noise ratios were successfully accomplished to identify optimal process parameters for improving the individual responses. The ANOVA and interaction was additional supports to enhance the mechanical properties. The scanning electron microscope was used to examine the fracture surfaces at the tensile fracture specimens with optimal conditions. Moreover, the maximum mechanical characteristics were attained by the increasing of nanocarbon fiber in the processed polymer matrix composites. [ABSTRACT FROM AUTHOR]

The aim of this study is to investigate the effect of isopropyl triisostearoyl titanate (KR-TTS) as a titanate coupling agent (TCA) on surface modification of TiO2 nanotube (TNT) material. From the physical and chemical studies that have been performed on the modified TiO2 nanotube, scanning electron microscope micrographs, energy-dispersive X-ray and viscosity indicated that there was significant reduction in particle aggregation of the modified TiO2 Nanotube. FTIR spectroscopy confirmed that the functional group of the TCA reacted with the hydroxyl groups present on the surface of TiO2 nanotube resulting in an altered surface property from being hydrophilic to hydrophobic. X-ray diffraction indicated that crystalline structure did not change upon the modification with the coupling agent. Isopropyl triisostearoyl titanate (KR-TTS) is found to be superior in performance and has a significant effect on the dispersion and resolving of agglomeration. This paper presents the effect of surface modification with the TCA of isopropyl triisostearoyl titanate (KR-TTS) type on the TiO2 nanotube material. [ABSTRACT FROM AUTHOR]

The main aim of this research is to analyze the mechanical performances of the influence of silicon carbide (SiC) particles with AA6351 aluminum alloy. The aluminum metal matrix composites were prepared with liquefying stir casting to produce the metal matrix composites (MMCs). The following weight fractions are AA6351-0% SiC, AA6351-2.5% SiC, AA6351-5% SiC, and AA6351-7.5% SiC utilized to compose the MMCs. The mechanical performances like hardness, flexural, impact, compressive, and tensile studies were investigated on the processed MMCs. The scanning electron microscope (SEM) was employed to examine the strengthened particle of SiC. During the SEM examinations, uniformly dispersed SiC-strengthened particles were analyzed. The entire MMCs specimens achieve greater mechanical characteristics; the specimen fabricated with a maximum volume fraction of 7.5 wt% of SiC accumulates higher strength than the other volume fractions samples. The SiC plays a very tedious role in improving mechanical attributes. The fabricated MMCs were highly utilized in the applications of automotive and aerospace usages. This application is fully employed with lesser weight and maximum strength conditions to fulfill the mechanical performances. The stir-casting process was a highly efficient technique to compose better MMCs to achieve greater strength. [ABSTRACT FROM AUTHOR]

One of the most fundamental subjects in nanoscience and nanotechnology is structural analysis. We employed a scanning electron microscope (SEM) image of the manufactured Gd3+/13X/DOX/FA nanocomposite in this study. The size, dimensions, and morphology of nanocomposite materials were studied to ensure the uniformity and homogeneity of SEM images. This is the first study to look at segmented SEM images for fractal dimension (FD) and other statistical criteria, including average, maximum, minimum, skewness, and range for magnetic resonance imaging (MRI) nanocomposite. The average of FD (FDavg), the standard deviation of FD (FDsd), and the lacunarity of FD (FDlac) fractal data analysis criteria were also employed. The findings show that particle sizes and shapes vary because the minimum-to-maximum range is not zero, and our data provide a reasonable range. This interpretation is further supported by an analysis of the nanocomposite's SEM image. At first glance, the image seemed to be uniform. However, when the calculations were performed, it was discovered that the generated particles were not particularly uniform. The particles were uniformly dispersed throughout all surfaces, although their sizes, dimensions, and morphologies varied. In conclusion, the study was supported by fractal data analysis, emphasizing the importance of structural analysis for future research, particularly for medical applications like MRI. [ABSTRACT FROM AUTHOR]

Titanium dioxide (TiO2) nanoparticles were prepared by the sol–gel method and the structural, morphological, and optical properties were investigated at different sintering temperatures of 500, 600, 700, 800, and 900°C. A tetragonal structure of anatase, mixed (anatase–rutile), and rutile phases are observed in the X-ray diffraction (XRD) analysis. Pure anatase phase formation occurred at 500°C, whereas anatase-to-rutile phase transformation began at 600°C, and reaching complete conversion to rutile at 800°C. The average crystallite size increased from 23 to 34 nm for anatase and 38 to 62 nm for the rutile when sintering temperature increased from 500 to 900°C. The scanning electron microscope (SEM) result presented the increase of grain size (25–100 nm) with increasing the sintering temperature. The Fourier transform infrared (FTIR) spectra demonstrated the presence of TiO2 vibrational bonds in all samples. The optical bandgaps of the sintered TiO2 nanoparticles decreased with rising sintering temperature. Photoluminescence spectra exhibited three characteristic peaks centered at 380, 450, and 550 nm. The emission intensity increased with increasing the sintering temperature. The Mie analysis was also studied to calculate scattering cross-section, forward scattering, and asymmetry for different grain sizes. The results showed that by increasing the nanoparticle diameters, the peaks of all spectra are redshifted for larger grain sizes and cross-section peaks shift to high values. In this study, the sintering temperature is observed to have a strong influence on crystalline phase transformation, microstructure, and optical properties of TiO2 nanoparticles. The TiO2 sample sintered at 900°C shows the best result to be used as luminescent material due to the low optical bandgap energy. [ABSTRACT FROM AUTHOR]

The spread of infectious diseases across the globe as a result of numerous bacterial and fungal variations has become a serious threat to human life. A critical global situation is the need to search for antibiotic resistance and develop new treatments. The most crucial role is for academics to advise the pharmaceutical industry about substances with antimicrobial assessments. One of the challenges in implementing novel medicine delivery is the discovery of compounds having antibacterial and antifungal characteristics against Gram-positive and Gram-negative bacteria and fungi. The superiority of the metal oxide-doped liquid crystal technology for antibiotic resistance is revealed. In this work, a bacterially triggered drug delivery system using a nanometal oxide-doped lipid-based liquid crystal system was explored. Copper oxide (CU) and cholesteryl stearate (CS) are processed using ultrasonication to produce the complex chemical in powder form (CSCU). Functional groups are predicted by Fourier transform infrared (FTIR) analyses, while surface appearance and dimensions that support the compound CSCU's biological characteristics are revealed by scanning electron microscope (SEM) and transmission electron microscope (TEM) analyses. Using the agar-well diffusion method, this substance was tested for antibacterial and antifungal activities against the Gram-positive bacteria Streptococcus pyogenes at various concentrations ranging from 0.6 to 1.25 µg/ml. Additionally, this substance exhibits a range of moderate to good antifungal efficacy against Aspergillus niger. [ABSTRACT FROM AUTHOR]

The aluminum metal matrix composites were broadly exploited in the applications of automotive, aerospace, and other defense with functionally graded materials-related application. Above applications definitely required excellent mechanical characteristics. Therefore, in this way, the major attempt was made on the nano-based composites with aluminum alloy utilization. In this research, aluminum alloy AA8011 and the ceramic-based reinforcement particles of nano boron carbide (B4C) were selected for producing the metal matrix composites by the liquefying process or stir casting route. The weight percentage of nano boron carbide particles having 15 wt% was subjected to add into the aluminum alloy during the stir casting process. Then, processed nano boron carbide and AA8011 specimens were prepared to conduct tribological behaviors with various processing conditions like sliding velocity, setting wear temperature, and applied load by the tribometer setup. The scanning electron microscope was employed to examine the processed composites samples and worn-out surface samples. Finally, the multiobjective optimization was used to measure the individual performances of the tribological parameters by the gray relational technique. [ABSTRACT FROM AUTHOR]

This study is focused on the application of activated carbon nanoadsorbent derived from Ocimum basilicum Linn (sweet basil) leaves for the removal of methyl orange dye from an aqueous solution. The Ocimum basilicum Linn leaves are dried, powdered, cured with H2SO4, and thermally treated to form an activated carbon biosorbent. Sorbent characterization studies like scanning electron microscope (SEM) and Fourier transform infrared (FTIR) spectroscopy have revealed the adsorption of the methyl orange dye from their aqueous solution in the batch mode process. The biosorbent has shown a maximum adsorption capacity of 1.54 mg g−1 at 10 mg l−1 concentration, 1.2 g sorbent dosage, pH of 3, contact time of 180 min, and pHpzc at 3.9. Experimental results are analyzed using equilibrium models and it is found that the Langmuir isotherm model and kinetic model fit well and also the results have corresponded well with pseudo-first order. The intraparticle diffusion (IPD) mechanism has shown that pore diffusion occurs at a slower rate. The Elovich model has displayed that adsorption is affected by film diffusion. From the statistical optimization studies, it is demonstrated that Box–Behnken model can correlate the good agreement between experimental and predicted values. The highest adsorption capacity for the nanoadsorbent was found using quadrate models and optimizing the variables at a time of 237 min, initial dye concentration of 5.31 mg l−1, adsorbent dose of 1.22 g, and pH of 4.23. [ABSTRACT FROM AUTHOR]

The green synthesis of zinc sulfide nanoparticles (ZnS NPs)-mediated plant extract is gaining importance because of its simplicity, cost-effectiveness, and ecofriendly nature. In this work, ZnS NPs were synthesized using garlic extract as NPs facilitating agent, characterized by Fourier transform infrared, X-ray diffraction, scanning electron microscope, and UV–visible, then their antibacterial and hemocompatibility were assayed. Analysis revealed a cubic phase, 2.33 nm crystallite size, and a 3.75 eV optical bandgap. Bioactivity test against Staphylococcus aureus and Escherichia coli indicated dose-dependent potency closer to that of azithromycin standard drug and more efficient on S. aureus (Gram-positive) than E. coli (Gram-negative) bacteria. Biocompatibility test in terms of erythrocyte hemolysis, in reference to normal saline and water as minimal and maximal controls, confirmed nontoxic substance up to 100 μg/mL as the highest examined concentration and at which a lysis of 2.9% was detected. Therefore, it could be concluded that this biogenic method is effective in producing ZnS NPs with desirable properties for potential biomedical applications. [ABSTRACT FROM AUTHOR]

Natural fiber composites are now more costly than traditional building materials. Currently, industries are moving from traditional materials to natural fiber composites, and the price of natural fiber should be reduced through greater utilization of industrial production. This work aims to determine how matrix alteration affects the interlaminar characteristics of a hemp fiber-reinforced epoxy composite containing nano silicon oxide particles. Interlaminar modulus of rupture in Types I and II is assessed using dual cantilevered beams and end-notched deformation testing samples. Mechanical mixing and sonication are used to blend nanoscale SiO2 (30 nm) into the resin at concentrations of 0, 0.2, 0.4, and 0.6 wt%. The composites were made using the compression molding method. The composites were tested according to the American Society for Testing and Materials standards after manufacturing. The findings show that adding nanoparticles enhances interlaminar toughness values. Interlaminar fracture toughness improved by 20.25% and 30.35% for 0.4 wt% SiO2, respectively. The fiber matrix interaction and failure causes are examined using scanning electron microscope images. [ABSTRACT FROM AUTHOR]

Titanium alloy-based components are now attracted by the industries with their distinguished properties even though they are difficult to machine. The tooling industries encounter numerous problems in machining these metals like higher tool wear, huge volumes of cutting fluid consumption, and shorter tool life. The objective of this research is to enhance the surface of the cutting tool with carbon nanotube (CNT) deposition to solve the aforementioned difficulties. This research used the plasma-enhanced chemical vapor deposition method to coat CNT on high-speed steel tools. Microstructural investigations were performed using a scanning electron microscope and a Raman spectroscopic technique to ensure the homogenous deposition of CNT. Additionally, scratch testing was also conducted to assess the adhesive strength of the deposited layer to the substrate. Finally, the machining performance of the CNT-coated tool was compared with commercially available diamond-like carbon (DLC) and titanium aluminum nitride (TiAlN)-coated tools. Machining experiments conducted under three distinct cutting levels revealed that the CNT-deposited tool is appropriate for turning more challenging materials. CNT-coated tools showed substantial decreases in cutting tooltip temperature, turning forces, and tool wear compared to DLC and TiAlN-coated tools. In particular, tool life studies conducted under elevated machining circumstances recorded the enhancement in tool life as 96.3% and 26.8% in comparison with TiAlN and DLC, respectively. [ABSTRACT FROM AUTHOR]

The simple, accurate, and rapid detection of foodborne pathogens is essential for public health. Development of an immunomagnetic separation (IMS) multiplex touchdown PCR (IMS–multiplex TD–PCR) assay for simultaneous detection and distinguishing of C. jejuni and C. coli is reported herein. Polyclonal antibody (pAb) against multiepitope antigen (MEA) was conjugated to ferromagnetic nanoparticles (FMNs) to produce anti-MEA FMNs. Optimal anti-MEA FMNs loading yielded 26.7 μg of immunoglobulin G (IgG) molecules per mg of FMNs with an average size of 72 ± 9 nm, corresponding to an 83% rate of pAb conjugation. Anti-MEA FMNs (20 μg) for IMS captured culturable C. jejuni cells at 3.54 × 10 2 colony-forming unit (CFU)/mL in pure culture, while higher amounts (40 and 60 μg) reduced the recovery. The scanning electron microscope (SEM) analysis revealed the attachment of anti-MEA FMNs to target bacteria, forming aggregated cells and magnetic nanoparticles in ellipse-like shapes. The subsequent multiplex TD–PCR assay simultaneously detected and distinguished C. jejuni and C. coli at 104 CFU/mL in mixed culture and at 103 CFU/mL for each individual species. Furthermore, the limit of detection (LOD) of the IMS–multiplex TD–PCR assay was 104 CFU/g in spiked chicken breast samples. Specificity was 100% for both C. jejuni and C. coli as none of the amplicons were detected in control samples where Campylobacter was absent. This assay is able to detect and distinguish C. jejuni and C. coli simultaneously and is simple, accurate, and rapid with a time to result of 4 h without an enrichment step, making it a promising approach for rapid and culture-free detection of Campylobacter in chicken products. [ABSTRACT FROM AUTHOR]

Organic fiber-based biocomposites have gained prominence in a variety of sectors over the last four to five years due to their exceptional mechanical and physical properties. Natural fiber-based composites are increasingly being employed in autos, ships, airplanes, and infrastructure projects. The current study will look at the effect of nanotitanium oxide (TiO2) fillers on the properties of hybridised jute-hemp-based composites. In this work, TiO2-filled biocomposites were created using the hand layup method in hybrid jute-hemp composites containing jute fiber mats, woven hemp mats, and epoxy resin. After nanotitanium oxide fillers were injected in various weight proportions, the mechanical properties of fiber-reinforced polymers were investigated. The mechanical properties of laminated composites were tested using the ASTM standard. Compared to 2 and 4 wt.% of TiO2, the 6 wt.% was provided the highest mechanical strength. Among the different types of specimen, the E-type specimen (30 wt.% of hemp, 7 wt.% of jute, 57 wt.% of epoxy, and 6 wt.% of TiO2) gives their highest contribution, i.e., for tensile 24.21%, for flexural 25.03%, and for impact 24.56%. The scanning electron microscope was utilized to analyse the microstructures of nanocomposites. [ABSTRACT FROM AUTHOR]

Organic fiber biocomposites have figured prominently in various industries of commerce during the last 3 to 5 years owing to their remarkable physical and mechanical abilities. The main purpose of this experimental research is to evaluate the biomechanical and geomorphologic belongings of nanostructured substance under naturalistic situations. To accomplish such a cognitive approach, flaxseed strands are employed as reinforcing, nano-based graphene as an additive, and epoxy as a matrix phase, with the following restrictions in imagination: (i) fiber lengths, (ii) fiber volume fraction, and (iii) weight proportions of nanoparticles. The nanocomposites are combined by means of the hand lay-up process based on the Taguchi orthogonal specification. The material characteristics of the substance, like bending, tension, and shock characteristics, are assessed in line with the standard specification. The material properties of mixtures' second levels are the highest when compared to all other configurations. The elastic modulus of nanoparticle biocomposites revealed that 2% graphene provides 32.39 percent, 4% graphene provides 36.39 percent, and 6% nanoparticle pertains to 31.23 percent. Fractured images captured using scanning electron microscope of cracked samples have been used to comprehend the overall failure mechanism of a composite in mechanical characterization. [ABSTRACT FROM AUTHOR]

In the past few years, researchers have turned away from previous metals and minerals and more towards lightweight materials throughout addition to creating lightweight, better effective composites for special tasks. The composite materials were created by employing the most advantageous hand layup approach. To attain the aforementioned goals, the following limitations were implemented: at various levels, (i) coconut shell powder, (ii) walnut powder, and (iii) cryogenic treatment hours are all accessible. At 77 K, the laminated composite was put in a cryogenic chamber. Tensile, flexural, and interlaminar shear strengths were all tested mechanically. In comparison to 100 μm coconut shell powder-based particle composites, 80 μm walnut shell composites gave the maximum mechanical strength, while 10 wt% coconut shell powder and walnut and 80 wt% polyester also had a beneficial impact. The morphological behaviour of the particulate material was detected using a scanning electron microscope (SEM). [ABSTRACT FROM AUTHOR]

A mixed microbiologically composite made from natural Linum usitatissimum fibers with nano-reinforced organic plastics can improve properties while being environmentally friendly. The inclusion of aluminium tris hydroxide particles into an organic polymer enables it to maintain stiffness without sacrificing durability, even while improving barriers and material characteristics. A study of numerous composite samples verified this complementary effect, with combinations including 10 percent EMS and 2.6 wt.% ATH retaining the resin's stiffness, stress to breakage, and mechanical properties while improving durability. Mechanical tests such as tensile and impact strength were discovered using the conventional ASTM test plan. Best-practice designs which maximize constituent interactions are thus attainable, and the research findings serve as the basis for discovering this balance, thereby broadening the spectrum of microbiologically polymer nanocomposites. The cracked surfaces of the nanomaterials, and the amount of dispersion of an ATH filler, were examined using a scanning electron microscope. [ABSTRACT FROM AUTHOR]

Electroless deposition or chemical coating is a well-established industrial technique that is gaining popularity. The purpose of the current investigation was to determine how long a heat treatment process had on the mechanical and corrosion performances of a Ni-P coating on low-carbon steel. The coating is performed on the low-carbon steel using Ni-P salt bath. The coated samples were heat treated at 400°C under atmospheric condition using muffle furnace. The heat treatment offers greater corrosion resistance and mechanical qualities. The coated samples were analysed using scanning electron microscope for morphological studies and X-ray diffraction analysis for phase change during heat treatment. According to the experimental findings, a heat treatment prior to coating with Ni-P layer increases hardness and corrosion resistance while lowering friction. [ABSTRACT FROM AUTHOR]

The aim of this study is to evaluate the wear and micro hardness of a Ti-6Al-4V matrix reinforced with 10% and 15% tungsten carbide particle (WCp) composite manufactured using the squeeze casting process. Optical microscopy is used to determine the microstructures of the composite. A pin-on-disc wear test equipment and Vickers hardness at atmospheric temperature were used to examine the wear behaviour wear rate, CoF, and micro hardness qualities of primed samples. Loads of 10 N to 80 N, velocities of 4 m/s, and distances of 1000 m to 2000 m are considered for analyzing the wear behaviour of Ti-6Al-4V composites. The wear rate values are 25.683 for 10% WCp, 30.957 for 15% WCp, and 37.683 and 30.957 for 20% WCp. A scanning electron microscope (SEM) is utilized to examine the worn surface of the composites. For 10% WCp, the CoF values are 0.82 and 0.87, and for 15% WC, 0.88 and 0.956. The micro hardness values are 692 VHN for 10% WCp and 835 VHN for 15% WCp. The wear rate, microstructure, SEM images, coefficient of friction, and hardness of TMCs for totaling reinforcing tungsten carbide particle (WCp) possessions were discovered to be improved. [ABSTRACT FROM AUTHOR]

The river sand is a primary parameter in the concrete structure. This work replaces accessible locally accessible substitution materials like red soil and manufactured sand (M-Sand). In this paper, the mechanical properties and durability of concrete containing red soil and M-Sand have been studied. In this investigation, M30 grade concrete was used, and tests were conducted for two sets of combinations; i.e., red soil as a partial replacement for river sand seems to be 20%, 30%, 40%, 50%, and 60%, and red soil as a partial replacement for manufactured sand (M-Sand) seems to be 60%, 50%, 40%, 30%, and 20%. The compressive strength (7 days, 28 days, 90 days), split tensile strength (28 days), and flexural strength (28 days) have been determined. The combination S4-50% river sand + 50 % red soil and S9-70% M- Sand + 30 % red soil gives more compressive strength than other combinations. Similarly, the combination S3-60% river sand + 40 % red soil and S6-40% M- Sand + 60 % red soil gives more flexural and split tensile strength than other combinations. The scanning electron microscope (SEM) analysis, EDAX analysis, and durability tests like alkalinity, sulfate attack, and chloride attack have also been studied. [ABSTRACT FROM AUTHOR]

With the popularization of oral health knowledge, people have gradually realized the importance of orthodontic treatment in oral health, so the number of patients undergoing orthodontic treatment has increased significantly. To improve the effect of orthodontic treatment, this article mainly studied the application of adhesives loaded with amorphous nanocalcium phosphate in the prevention of enamel demineralization in orthodontic patients. In the experiment, we used spray-drying technology to synthesize NACP. The collected dry particles were dispersed with absolute ethanol, sonicated for 10 minutes, dropped on a 200 ordinary carbon support film, and then dried and observed with a transmission electron microscope (TEM). Prevention of enamel demineralization in orthodontic patients was by adhesive-loaded amorphous nanocalcium phosphate. In this experiment, the membrane dialysis method was used to release the drug-loaded nanoparticles. The MH-5 microhardness tester was used to randomly select 3 positions on the buccal area of the enamel surface to measure the microhardness. After measuring the microhardness of each point, take the average of the readings of the 3 positions. Before and after the experiment, the difference of the enamel surface microhardness before and after the experiment was statistically analyzed. Before the scanning electron microscope observation, to avoid contamination of the window area of the enamel surface, which will cause interference with the scanning electron microscope observation, we use acetone to remove the acid-resistant nail polish coated on the enamel surface. Clean the attachments on the surface of the teeth first, then fix, dehydrate, and dry. When the release time reaches 52 h, the cumulative release rates of Cur in pH 5.4 and pH 7.4 buffers are 85.84 and 64.68%, respectively. The results show that by adjusting the concentration of PAA, it is possible to configure a mineralized liquid that can not only use the fluidity of NACP to penetrate into the collagen fibers but also transform into HAP within a suitable time, to achieve the purpose of repairing demineralized dentin. [ABSTRACT FROM AUTHOR]

During the stir casting process, different percent weights of hexagonal boron nitride (HBN) and cubic boron nitride (CBN) were mixed with aluminum alloy 6061. The test specimens are then machined from the cast aluminum metal matrix composites. The tests are carried out utilizing an ASTM G99-compliant pin-on-plate tribometer on a pivoting EN32 circle. Minitab 16 is used to plan the dry sliding wear trials, which are set up in an orthogonal array. The input parameters are percent HBN addition and CBN addition, sliding speed, and load, and the wear rate was considered to be the output parameter. The actual density of the cast specimens was found to be greater than 90% of their theoretical density. The accumulation of HBN and CBN greatly enhances the wear resistance of aluminum metal matrix composites, according to research. The technique of regression analysis is utilized to establish genuine links between the wear rate and input parameters. The morphology of the worn out surfaces was examined using a scanning electron microscope (SEM). After numerous iterations, the simulation source of DEFORM 3D forecasts the stress and velocity component of the frictional surface contact area. [ABSTRACT FROM AUTHOR]

In today's world of electronics, nanomaterial applications pose a challenge. The spin coating approach was used to create nanostructured ZnO with wurtzite structure in a recent study. Antimony doping, aluminum, and antimony codoping with 2.0 percent were used to make these films. The impact of doped and codoped films on structural, optical properties, and morphological has been examined using a variety of characterization approaches. A ZnO nanocrystal with a diameter of 20-30 nm was discovered using XRD (X-ray diffraction). According to SEM (scanning electron microscope) scans, the grain size is in the 80-120 nm region. The use of Fourier transform infrared spectroscopy (FTIR) to detect elemental elements was studied, and the peak at 400-520 cm-1 was identified as ZnO. The optical properties of doped and codoped ZnO were checked, and it was discovered that antimony-doped ZnO has a larger band gap than Al and antimony-codoped ZnO. This proved that ZnO may be used in gas sensors and solar cells. The gas response of a static gas sensor system based on Sb-doped films was measured and compared to Al- and Sb-codoped films in the presence of ethanol vapor. [ABSTRACT FROM AUTHOR]

Recently, nontoxic origin-mediated synthesis of copper oxide nanoparticles acquires further recognition because of the key role of bioapplications. The plant Cissus quadrangularis is one most prominent herbs used in the treatment of diabetes, asthma, tissue regeneration, etc. In this study, we tested the process of copper oxide nanoparticle synthesis and their role in many functions from Cissus quadrangularis. The synthesis of copper oxide nanoparticles uses plant extract and characterization by X-ray diffraction, thermogravimetric analysis (TGA), Fourier-transform infrared spectroscopy (FT-IR), atomic force microscope (AFM), and scanning electron microscope (SEM). The synthesized nanoparticles were analyzed for their biomedical applications such as antibacterial, antifungal, antioxidant, antidiabetic, and anti-inflammatory activity and antiproteinase action. The results show that the C. quadrangularis plant-mediated nanoparticles may be used in many biomedical applications related to arthritis, diabetes, and the production of various antimicrobial products in the future. [ABSTRACT FROM AUTHOR]

Recycling wastes and providing their use in useful fields attract attention every day. In our study, with the extract prepared from the parts of the Cynara scolymus L. (artichoke) plant that is not suitable for human consumption, silver nanoparticles were easily synthesized in an ec-friendly, energy-free way. Characterization of the obtained nanoparticles was done with a UV-visible spectrophotometer (UV-Vis.), fourier transform infrared spectroscopy (FTIR), X-ray diffraction diffractometer (XRD), scanning electron microscope (SEM), transmission electron microscopy (TEM), and zeta potential analysis data. In these data, it was determined that AgNPs have a maximum absorbance at 458.8 nm wavelength, a crystal nanosize of 28.78 nm, and a spherical appearance. The zeta potential of (-) 16.9 mV indicates that silver nanoparticles exhibit a stable structure. Particles show antimicrobial effects on pathogenic species at concentrations of 0.03-0.25 μg/ml, and it was determined by using the minimum inhibition concentration (MIC) microdilution method. By examining their cytotoxic effects on U118, CaCo-2, and Skov-3 cancer cell lines and healthy HDF cell lines by the MTT method, concentrations of inhibitive effects on survival were determined. [ABSTRACT FROM AUTHOR]

Nanotechnology from titanium dioxide has been deposited, and its application in desalination and water treatment has been investigated by using sol-gel methods. Homogeneously dispersed sphere shapes of titanium dioxide nanoparticles were observed from scanning electron microscope micrographs and decrease in size as aging time increases from 40 min to 60 min. SEM micrographs of highly transparent nanopowders show that they are detected in the visible region from UV/visible and that their red shift around maximum wavelength increases with increasing aging time due to an increase in water quality. The energy band gap of the generated nanosheet has narrowed as the aging time has increased, which is related to the red shift of the absorption spectrum edge in the sheet. The structural behaviors of deposited nanoparticles have also been investigated, which confirms the existence of anatase as well as rutile levels in the liquid phase. The findings of the PL allowed us to determine the total strength of the intensity. This shows that applying photodegradation by a solar absorber could play a vital role in desalination and water treatment. [ABSTRACT FROM AUTHOR]

In this paper, a magnetic graphene oxide (MGO) composite was prepared by the click reaction between the alkyne-modified Fe3O4 nanoparticles and the azide-modified graphene oxide for the purpose of removing the Congo red (CR) dye from water. The deposition of the Fe3O4 nanoparticles on the graphene oxide to successfully prepare the MGO composite was evidenced by the Fourier-transform infrared spectrometer, wide-angle X-ray diffraction equipment, scanning electron microscope, thermal gravimetric analyzer, and Raman spectrometer. The value of saturation magnetization for the MGO composite was 34.9 emu/g. The CR absorption capacities of the MGO composite increased first and then decreased as the pH value increased. It was found that the maximum adsorption capacity of the MGO composite for the CR was as high as 769.2 mg/g. In the absorption-desorption experiment, the CR absorption capacities of the MGO composite from the second cycle to the fifth cycle remained stable to be about 130 mg/g. Moreover, both the Langmuir model for the adsorption isotherm and the pseudo-second-order kinetic model could be used to describe the CR absorption behaviors of the MGO composite. [ABSTRACT FROM AUTHOR]

The combination of tissue-engineered bone scaffolds with osteogenic induction molecules is an important strategy for critical-sized bone defects repair. We synthesized a novel thiolated chitosan/calcium carbonate composite microsphere (TCS-P24/CA) scaffold as a carrier for bone morphogenetic protein 2- (BMP2-) derived peptide P24 and evaluated the release kinetics of P24. The effect of TCS-P24/CA scaffolds on the proliferation and differentiation of bone marrow mesenchymal stem cells (BMSCs) was evaluated by scanning electron microscope (SEM), CCK-8, ALP assay, alizarin red staining, and PCR. A 5 mm diameter calvarial defect was created, then new bone formation was evaluated by Micro-CT and histological examination at 4 and 8 weeks after operation. We found the sequential release of P24 could last for 29 days. Meanwhile, BMSCs revealed spindle-shaped surface morphology, indicating the TCS-P24/CA scaffolds could support cell adhesion and mRNA levels for ALP, Runx2, and COL1a1 were significantly upregulated on TCS-10%P24/CA scaffold compared with other groups in vitro (p < 0.05). Similarly, the BMSCs exhibited a higher ALP activity as well as calcium deposition level on TCS-10%P24/CA scaffolds compared with other groups (p < 0.05). Analysis of in vivo bone formation showed that the TCS-10%P24/CA scaffold induced more bone formation than TCS-5%P24/CA, TCS/CA, and control groups. This study demonstrates that the novel TCS-P24/CA scaffolds might contribute to the delivery of BMP2-derived Peptide P24 and is considered to be a potential candidate for repairing bone defects. [ABSTRACT FROM AUTHOR]

The possibility of obtaining calcium carbonate nanoparticles from Achatina fulica shell through mechanochemical synthesis to be used as a modifying filler for polymer materials has been studied. The process of obtaining calcium carbonate nanopowders includes two stages: dry and wet milling processes. At the first stage, the collected shell was dry milled and undergone mechanical sieving to ≤50 μm. The shell particles were wet milled afterward with four different solvents (water, methanol, ethylene glycol, and ethanol) and washed using the decantation method. The particle size and shape were investigated on transmission electron microscopy, and twenty-three particle counts were examined using an iTEM image analyzer. Significantly, nanoparticle sizes ranging from 11.56 to 180.06 nm of calcium carbonate was achieved after the dry and wet milling processes. The size particles collected vary with the different solvents used, and calcium carbonate synthesis with ethanol offered the smallest organic particle size with the average size ranging within 13.48-42.90 nm. The effect of the solvent on the chemical characteristics such as the functional group, elemental composition, and carbonate ion of calcium carbonate nanopowders obtained from Achatina fulica shell was investigated. The chemical characterization was analyzed using Fourier transform infrared (FTIR) and a scanning electron microscope (SEM) equipped with an energy-dispersive spectroscope (EDX). The effect of milling procedures on the mechanical properties such as tensile strength, stiffness, and hardness of prepared nanocomposites was also determined. This technique has shown that calcium carbonate nanoparticles can be produced at low cost, with low agglomeration, uniformity of crystal morphology, and structure from Achatina fulica shell. It also proved that the solvents used for milling have no adverse effect on the chemical properties of the nano-CaCO3 produced. The loading of calcium carbonate nanoparticles, wet milled with different solvents, exhibited different mechanical properties, and nanocomposites filled with methanol-milled nano-CaCO3 offered superior mechanical properties. [ABSTRACT FROM AUTHOR]

The porous silicon as substrate material was prepared by metal-assisted chemical etching (MACE) method. The TiO2 nanowire cover layer on porous silicon was prepared by hydrothermal method. Thus, porous Si/TiO2 nanowire heterostructure was obtained. The formation of the porous Si/TiO2 nanowire heterostructure was confirmed by X-ray diffraction (XRD) and scanning electron microscope (SEM). The results of diffuse reflection spectra (DRS) show that porous Si/TiO2 nanowire has the highest antireflectivity among the four tested samples. Photoelectric catalysis (PEC) and photocurrent measurement show that the porous Si/TiO2 nanowire heterostructure has higher photoelectric catalytic and photocurrent activity than the other samples under the simulated solar light and visible light irradiation. The results showed that the construction of the porous Si/TiO2 nanowire heterostructure improved the photoelectrochemical properties, which is attributed to the heterogeneous effect and window effect. [ABSTRACT FROM AUTHOR]

Calcium nitrate (CN) is used widely as an effectively inorganic setting accelerator and antifreeze admixture in concrete structures. In this paper, the multiscale investigation of CN on the hydration of C3S was studied by scanning transmission X-ray microscopy (STXM) combined with near-edge X-ray absorption fine structure (NEXAFS), 29Si MAS NMR, calorimetry, scanning electron microscope, and N2 absorption. It was concluded that the calcium silicate hydrate (C-S-H) surrounds the unhydrated C3S at 1-day hydrated C3S in the presence of calcium nitrate, while portlandite is partly in transformation and is formed partly. Based on Ca L 3 , 2 -edge NEXAFS spectra for 1-day hydrated C3S particle, calcium nitrate does not change the structure of the asymmetrically 7-fold coordination of calcium in the C-S-H. Calcium nitrate can accelerate the hydration of C3S to some extent and polymerization of the silicate chains within C-S-H considerably at early age, resulting in the increasing specific surface area. [ABSTRACT FROM AUTHOR]

The process of obtaining aqueous solutions of silver nanoparticles with the use of a low-temperature nonequilibrium contact plasma and stabilizing agent—polysaccharide (sodium alginate)—has been examined. The synthesized Ag NPs were characterized by using UV-Vis spectroscopy, dynamic light scattering (DLS), scanning electron microscope (SEM), and XRD analysis. The effect of concentration of Ag+, sodium alginate, duration of processing by plasma discharge, and pH of liquid on the production of silver nanoparticles has been studied. The results demonstrated that synthesis provides the formation of silver nanoparticles for investigated concentrations of Ag+ (0.3-3.0 mmol/l) and 5.0 g/l Na-Alg (pH = 7 –10) within 1–5 minutes. From the SEM images, the silver nanoparticles are found to be almost spherical. Powder XRD results reveal that Ag nanoparticles have a face-centered cubic crystal structure. Zeta potential of plasma-chemically obtained colloidal solutions at various concentrations of Ag+ ions and stabilizing agent varies from −32.8 to −39.3 mV, indicating the moderate stability of synthesized nanoparticles. [ABSTRACT FROM AUTHOR]

A new kind of zeolite capsule complex with ferriferous oxide (Fe3O4) materials was prepared in this work. Its morphology was characterized via the scanning electron microscope (SEM), the high-resolution transmission electron microscopy (HRTEM), N2 adsorption analysis, and X-ray powder diffraction, respectively. The mesoporous nickel-based complex electrodes using substrate coating exhibited excellent energy storage properties through electrochemical testing. The high specific capacitance of 739.8 F g−1 was achieved at the current density of 1 A g−1 in a 6 M KOH solution. The good capacitance retention can retain 72.8% after 1000 cycles in a current density of 1 A g−1. The energy storage mechanism of the nickel-based complex electrodes was also analyzed. Furthermore, the asymmetrical supercapacitors (ASCs) were fabricated using the zeolite capsule complex with Fe3O4 as positive electrodes and the AC as negative electrodes, which performs high specific capacitance, outstanding energy density, superb power density, excellent cycle life, and small internal impedance. Those results suggest that the mesoporous nickel-based zeolite capsule complex with Fe3O4 as an electrode would be an ideal candidate material for supercapacitor applications. [ABSTRACT FROM AUTHOR]

Multiwalled carbon nanotubes (MWCNTs) were modified by oxidizing agent to obtain O-MWCNTs, and the surface of it was coated with active group. 4,4′-Diaminodiphenylmethane bismaleimide (MBMI) was used as matrix, 3,3′-diallyl bisphenol A (BBA) and bisphenol-A diallyl ether (BBE) were used as reactive diluent, polyethersulfone (PES) as toughening agent, and O-MWCNTs as modifier; OMWCNT/PES-MBAE composite was prepared through in situ sol-gel method. The effect of PES and OMWCNTs on the mechanical and dielectric properties of composite was analyzed, and the microstructure was examined by transmission electron microscope (TEM) and scanning electron microscope (SEM). The mechanism of composite toughened by PES and OMWCNTs was observed and analyzed. The results showed that Diels-Alder reaction between MBMI and allyl compounds occurred completely and unsaturated double bond disappeared. O-MWCNTs and PES resin dispersed smoothly in polymer matrix and were used as reinforcement, and PES resin and O-MWCNTs could synergistically improve the properties of the composite and exhibited a typical ductile fracture. The impact and bending strengths were 16.09 kJ/m2 and 153.57 MPa, which were 74.32% and 53.08% higher than those of the MBAE matrix, respectively, and the dielectric constant and the dielectric loss were 3.76 (100 Hz) and 2.79 × 10−3 (100 Hz), when the content of PES was 2 wt% and O-MWCNTs was 0.02 wt%. The outstanding properties of the material made it play an important role in high-performance insulating material applications. [ABSTRACT FROM AUTHOR]

We report a sputtered PdO decorated TiO2 sensing layer by radiofrequency (RF) sputtering methods and demonstrated gas sensing performance for H2 gas. We prepared sputtered anatase TiO2 sensing films with 200 nm thickness and deposited a Pd layer on top of the TiO2 films with a thickness ranging from 3 nm to 13 nm. Using an in situ TiO2/Pd multilayer annealing process at 550°C for 1 hour, we observed that Pd turns into PdO by Auger electron spectroscopy (AES) depth profile and confirmed decorated PdO on TiO2 sensing layer from scanning electron microscope (SEM) and atomic-force microscope (AFM). We also observed a positive sensing signal for 3, 4.5, and 6.5 nm PdO decorated TiO2 sensor while we observed negative output signal for a 13.5 nm PdO decorated one. Using a microheater platform, we acquired fast response time as ~11 sec and sensitivity as 6 μV/ppm for 3 nm PdO under 33 mW power. [ABSTRACT FROM AUTHOR]

Microwave-assisted chemical bath deposition (MW-CBD) was used to deposit zinc oxide nanorods (ZnO-NRs) films by using different microwave irradiation time. The films exhibit a good crystallinity having a hexagonal wurtzite phase formation. Although the dominant preferred orientation was not observed for the ZnO-5 and ZnO-10, ZnO-8 showed (002) preferred orientation. The emission scanning electron microscope (FESEM) showed almost randomly oriented hexagonal nanorods on the surface. A slight decrease in the length of the observed hexagonal nanorods due to the increase in the irradiation time was observed, changing from 550 nm to 300 nm. The p-Si/n-ZnO-NRs heterojunction photodiodes were fabricated. The current-voltage characteristics of these photodiodes were investigated under dark and different illumination intensity. An increase in the reverse current with increasing illumination intensity confirmed that the fabricated photodiodes exhibited a photoconducting behavior. In addition, the barrier height and series resistance values of the photodiodes were determined from capacitance-voltage measurements. [ABSTRACT FROM AUTHOR]

Polypropylene (PP) composites reinforced with multiwalled carbon nanotubes (MWNTs) were prepared by using twin screw extruder. The experimental results showed that with the increasing amount of MWNTs the elongation at break decreased whereas the tensile strength, bending strength, and impact strength increased. By using scanning electron microscope (SEM), we find that the hydroxyl-modified carbon nanotube has better dispersion performance in PP and better mechanical properties. [ABSTRACT FROM AUTHOR]

We investigated the effect of poly(3,4-ethylenedioxythiophene)-poly(styrenesulfonate) (PEDOT:PSS) deposition on the chemical and mechanical stability of Ag nanowire flexible electrodes. A large number of bending cycles, up to 500,000 cycles, were imposed on the Ag nanowire electrodes with and without PEDOT:PSS overcoating layer. In situ resistance measurement during bending tests revealed that the Ag nanowire electrode with PEDOT:PSS overcoating layer was mechanically reliable, showing a 21.9% increase in resistance after 500,000 cycles of bending. Scanning electron microscope images revealed that the failure of the Ag nanowire network occurred along with cracks initiated in the PEDOT:PSS layer, which resulted in the increase in resistance under bending. Furthermore, the PEDOT:PSS deposition enhanced the chemical stability of Ag nanowire electrode, which showed no significant increase in resistance after exposure in air for 50 days. Our study underscored that PEDOT:PSS is effective in protecting the Ag nanowires, while maintaining the high mechanical stability. [ABSTRACT FROM AUTHOR]

Mesoporous metal-organic framework-5 (MOF-5), with the composition Zn4O(BDC)3, showed a high capacity for the adsorptive removal of Pb(II) from 100% aqueous media. After the adsorption process, changes in both morphology and composition were detected using a scanning electron microscope (SEM) equipped with an energy dispersive X-ray (EDX) system, Fourier transform infrared spectroscopy (FTIR), and X-ray photoelectron spectroscopy (XPS) analysis. The experimental evidence showed that Zn(II) liberation from MOF-5 structure was provoked by the water effect demonstrating that Pb(II) removal is not due to ionic exchange with Zn. A kinetic study showed that Pb(II) removal was carried out in 30 min with a behavior of pseudo-second-order kinetic model. The experimental data on Pb(II) adsorption were adequately fit by both the Langmuir and BET isotherm models with maximum adsorption capacities of 658.5 and 412.7 mg/g, respectively, at pH 5 and 45°C. The results of this work demonstrate that the use of MOF-5 has great potential for applications in environmental protection, especially regarding the removal of the lead present in industrial wastewaters and tap waters. [ABSTRACT FROM AUTHOR]

Hollow ZnSnO3 nanospheres were synthesized by a hydrothermal method using ZnO nanospheres as the hard template and raw material simultaneously. The combined characterizations of X-ray diffraction (XRD), scanning electron microscope (SEM) and high-resolution transmission electron microscopy (HRTEM) confirmed the successful preparation of hollow ZnSnO3 nanospheres. The gas-sensing results indicated that the sensor made from hollow ZnSnO3 nanospheres exhibited high sensitivity, good selectivity, and stability to ethanol at a low operating temperature of 200°C. The sensitivity was about 32 and the response and recovery time were about 4 s and 30 s for 100 ppm ethanol, respectively. The enhancement in gas-sensing properties was attributed to the hollow nanostructures and high specific surface areas of ZnSnO3. [ABSTRACT FROM AUTHOR]

To improve the photoelectric property of polyaniline (PANI) counter electrode using for flexible dye-sensitized solar cell (DSSC), graphene (GN) was doped in PANI films covered on flexible conducting substrate by one-step electrochemical method, and then GN/PANI composites are characterized by scanning electron microscope (SEM), fourier transform infrared spectroscopy (FTIR), four probe instrument, and so on. The results show that PANI particles can be electrodeposited on the surface of GN sheets as the potential rising to 2.0 V. This formed unique PANI-GN-PANI lamellar structure owing to the strong interaction of conjugated π electron between GN and PANI results in the superior conductivity and catalytic performance of GN/PANI electrode. The maximum conversion efficiency of dye-sensitized solar cell with this counter electrode reaches 4.31%, which is much higher than that of GN-free PANI counter electrode. [ABSTRACT FROM AUTHOR]

Conductive poly(3,4-ethylenedioxythiophene)-poly(4-styrene sulfonate) (PEDOT:PSS) was incorporated into nanohydroxyapatite/chitosan (nHA/CS) composite scaffolds through a freezing and lyophilization technique. The bionanocomposite conductive scaffold was then characterized using several techniques. A scanning electron microscope image showed that the nHA and PEDOT:PSS were dispersed homogeneously in the chitosan matrix, which was also confirmed by energy-dispersive X-ray (EDX) analysis. The conductive properties were measured using a digital multimeter. The weight loss and water-uptake properties of the bionanocomposite scaffolds were studied in vitro. An in vitro cell cytotoxicity test was carried out using mouse fibroblast (L929) cells cultured onto the scaffolds. Using a freezing and lyophilization technique, it was possible to fabricate three-dimensional, highly porous, and interconnected PEDOT:PSS/nHA/CS scaffolds with good handling properties. The porosity was 74% and the scaffold’s conductivity was 9.72±0.78 μS. The surface roughness was increased with the incorporation of nHA and PEDOT:PSS into the CS scaffold. The compressive mechanical properties increased significantly with the incorporation of nHA but did not change significantly with the incorporation of PEDOT:PSS. The PEDOT:PSS-containing nHA/CS scaffold exhibited significantly higher cell attachment. The PEDOT:PSS/nHA/CS scaffold could be a potential bionanocomposite conductive scaffold for tissue engineering. [ABSTRACT FROM AUTHOR]

Series of WO3/TiO2 nanocomposites were obtained by hydrothermal method followed by calcination in the temperature range from 400°C to 900°C. The characteristics of photocatalysts by X-ray diffractometry (XRD), scanning electron microscope (SEM), and diffuse reflectance spectroscopy (DRS) showed that increasing the calcination temperature from 400 to 900°C resulted in change of photocatalytic activity under UV-Vis light. Moreover, the amount of WO3 crystalline phase and amorphous phase in WO3/TiO2 aggregates, as revealed by XRD analysis, was dependent on the calcination temperature. The WO3/TiO2 samples with 8 mol% load of WO3 in respect to TiO2 calcinated at 500 and 800°C possess the highest photocatalytic activity in reaction of phenol degradation, which is about 1.2 and 1.5 times that with calcination at 400°C. The increase in calcination temperature above 400°C resulted in increase of WO3 crystallinity and reduction of the amount of amorphous phase in the nanocomposite structure. Moreover, the annealing of nanocomposites above 700°C decreases the value of optical band gap energies of obtained WO3/TiO2 nanomaterials. [ABSTRACT FROM AUTHOR]

Three-point bending tests were performed on double-anchored, 110 silicon nanowire samples in the vacuum chamber of a scanning electron microscope (SEM) via a micromanipulator equipped with a piezoresistive force sensor. Nanowires with widths of 35 nm and 74 nm and a height of 168 nm were fabricated. The nanowires were obtained monolithically along with their 10 μm tall supports through a top-down fabrication approach involving a series of etching processes. The exact dimension of wire cross sections was determined by transmission electron microscopy (TEM). Conducting the experiments in an SEM chamber further raised the opportunity of the direct observation of any deviation from ideal loading conditions such as twisting, which could then be taken into consideration in simulations. Measured force-displacement behavior was observed to exhibit close resemblance to simulation results obtained by finite element modeling, when the bulk value of 169 GPa was taken as the modulus of elasticity for 110 silicon. Hence, test results neither show any size effect nor show evidence of residual stresses for the considered nanoscale objects. The increased effect of the native oxide with reduced nanowire dimensions was captured as well. The results demonstrate the potential of the developed nanowire fabrication approach for the incorporation in functional micromechanical devices. [ABSTRACT FROM AUTHOR]

This study reports the manufacture, microstructure, and tribological behaviour of carbon nanotube reinforced aluminium composites against pure aluminium. The specimens were fabricated using powder metallurgy method. The nanotubes in weight percentages of 0.5, 1.0, 1.5, and 2.0 were homogeneously dispersed and mechanically alloyed using a high energy ball milling. The milled powders were cold compacted and then isothermally sintered in air. The density of all samples was measured using Archimedes method and all had a relative density between 92.22% and 97.74%. Vickers hardness increased with increasing CNT fraction up to 1.5 wt% and then reduced. The microstructures and surfaces were investigated using high resolution scanning electron microscope (SEM). The tribological tests showed that the CNT reinforced composites displayed lower wear rate and friction coefficient compared to the pure aluminium under mild wear conditions. However, for severe wear conditions, the CNT reinforced composites exhibited higher friction coefficient and wear rate compared to the pure aluminium. It was also found that the friction and wear behaviour of CNT reinforced composites is significantly dependent on the applied load and there is a critical load beyond which CNTs could have adverse impact on the wear resistance of aluminium. [ABSTRACT FROM AUTHOR]

T10 steel slid against 20CrMnTi steel on a pin-on-disc wear test rig. Optical Microscope (OM), scanning electron microscope (SEM), and High Resolution Transmission Electron Microscope (HRTEM) methods were used to analyze the microstructures in the worn surface layers. The microstructures in the worn surface layers of pins and discs were all severely plastically deformed. Furthermore, the ultrafine and even nanoferrite structure (10 nm to 100 nm) was observed when the normal load reached 60 N. The mechanism of forming nanocrystalline structure in the sliding friction induced deformation layer (SFIDL) was elucidated as the result of the simultaneous and recursive actions of (i) severe shear deformation and (ii) friction heat on the contact surface. [ABSTRACT FROM AUTHOR]

This work reports for the first time electrosynthesis of hexanethiol capped silver nanotriangles cores (Ag@C6SH NCs) by a rapid, clean, and simple Double Pulse Chronopotentiometric (DCP) method in nonaqueous media, using a Taguchi orthogonal array L8 design to identify the optimized experimental conditions. It was found that the size and shape of the product could be tuned by the current density, electrolysis time, electrode distance, and amount of NaBH4% used. The Ag@C6SH NCs in different shapes and sizes (in the range of 30 to 44 nm as an average estimation) were synthesized, under different experimental conditions. Finally, the as-prepared nanoclusters electrosynthesized at optimized conditions were characterized by SEM, XRD, and UV-Vis spectroscopy. The average particle size of the triangular/pyramidal shape (Ag@C6SH NCs), obtained under optimized experimental conditions, was 30.5±2.0 nm but the majority of nanoparticles in TC3 SEM are so much finer. [ABSTRACT FROM AUTHOR]

WO3 hierarchical porous structures were successfully synthesized via cetyltrimethylammonium bromide- (CTAB-) assisted hydrothermal method. The structure and morphology were investigated using scanning electron microscope, X-ray diffractometer, transmission electron microscopy, X-ray photoelectron spectra, Brunauer-Emmett-Teller nitrogen adsorption-desorption, and thermogravimetry and differential thermal analysis. The result demonstrated that WO3 hierarchical porous structures with an orthorhombic structure were constructed by a number of nanoparticles about 50–100 nm in diameters. The H2 gas sensing measurements showed that well-defined WO3 hierarchical porous structures with a large specific surface area exhibited the higher sensitivity compared with products without CTAB at all operating temperatures. Moreover, the reversible and fast response to H2 gas and good selectivity were obtained. The results indicated that the WO3 hierarchical porous structures are promising materials for gas sensors. [ABSTRACT FROM AUTHOR]