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This paper focuses on the evaluation of the strength development and microstructure of nano-calcium carbonate (CaCO3) cemented paste backfill experimentally cured under isothermal conditions at room temperature and non-isothermal conditions in the field. A series of mechanical (uniaxial compressive strength, UCS) and microstructural (thermogravimetric, mercury intrusion porosimetry, scanning electron microscope) tests as well as monitoring experiments are experimentally conducted on cemented paste backfill (CPB) specimens with and without nano-calcium carbonate and cured at different times and under isothermal or non-isothermal conditions. The results show that the addition of nano-CaCO3 particles to CPB significantly improves its mechanical strength, irrespective of the thermal curing conditions (isothermal, field non-isothermal conditions). However, the impact of nano-CaCO3 particles on the increase in strength of CPB is only effective or significant at the early ages (curing time≤7 days). It is also found that the higher temperatures improve the accelerating effect of nano-CaCO3 much more than they accelerate the PCI hydration reactions in the first 3 days. Moreover, it is also found the sulphate ions present in the natural gold tailings negatively affect the mechanical performance of nano-CPB and reduced the accelerating effect of nano-CaCO3 due to sulphate attacks. [ABSTRACT FROM AUTHOR]

Due to the high demand for cement-based materials in buildings, graphene has been widely studied as a potential new cement composite reinforcement agent. In this study, polycarboxylate (PC) Superplasticizer, Tetraoxatetradecan-1-ol,14-(nonylphenoxy)-(CO520), Sodium dodecyl-benzenesulfonate (SDBS), Sodium cholate (SC), and Hexadecyl trimethyl ammonium Bromide (CTAB) were used as surface-active agents (SAA). The effects of different graphene contents (0, 0.01%, 0.03%, 0.05%, and 0.07%) on the mechanical properties were experimentally evaluated and analyzed. The results showed that under the same curing condition, when the graphene content is 0.03% (PC as SAA), the mechanical properties arrived at maximum. Compared with the control group, the compressive strength with 3, 14, and 28 curing days, achieved the improvement of 23.49%, 28.75%, and 33.99%, respectively. The flexural strength had the improvement of 22.18%, 25.11%, and 27.18%, respectively. The Scanning electron microscope (SEM), Diffraction of X-rays (XRD), Ultraviolet-visible Spectrophotometer (UV), Energy Dispersive Spectroscopy (EDS) and Raman analysis proved that graphene promoted the hydration reaction, and it played a filling effect and template role in the mortar matrix. Ultimately, when graphene content is within the appropriate range, the filling effect and the unplugging effect of graphene can effectively improve the performance of the mortar. [ABSTRACT FROM AUTHOR]

Spore balls of false smut of rice caused by Ustilagonoidea virens were collected from different major rice belts of eastern part of India. Ten isolates from ten different locations were collected and isolated in the laboratory for their, cultural, morphological and molecular characterization. Potato sucrose agar media was used for their cultural studies and observation on colony diameter, colour and sporulation were made. Spores of all the isolates were observed under scanning electron microscope (SEM) and light microscope for spore size, spine length and colour. Differences in colony characters were observed where the highest mycelial growth was observed in isolate Uv2 with 5.33 cm colony diameter and lowest mycelial growth was observed in Uv9 (3.70 cm). Most of the isolates produced white and circular colony. Spores of all the isolates observed under a light microscope appeared to be olive green in colour, however, a significant variation in spore size and spike length under SEM was observed. Spores size and spike length of different isolates ranged between 4.533 μm to 6.169 μm and 362.567 nm to 799.533 nm, respectively. For genetic identification and variability, DNAs of isolates were amplified using ITS1 and ITS 4 primers. The length of nucleotide sequences of different isolates varied from 583 to 606 bp. Phylogenetic analysis revealed genetic variation among the isolates, dividing them into two major groups. [ABSTRACT FROM AUTHOR]

High-speed impact behaviour of composite sandwich panels reinforced by nano-SiO2 has been studied in the present article. The sandwich panels were manufactured by glass/fibre epoxy composite face sheets and an M-shaped core using the vacuum-assisted resin transfer moulding (VARTM) method. To enhance the mechanical strength of the matrix, especially impact resistance, the nanoparticles were added to the resin epoxy matrix as filler. A scanning electron microscope (SEM) was utilised to observe the microscopic structure of the composites. The experimental results indicated that adding 1–3 wt-% of nano-SiO2 into the matrix remarkably increased the impact resistance of the composite. In order to validate the results, the experimental data were compared to the finite element models, and good agreement was observed. [ABSTRACT FROM AUTHOR]

The origin of dolostones from the Lei 4 Member (T2l4) of the Middle Triassic Leikoupo Formation in the Western Sichuan Depression is unclear. The occurrence and genetic evolution of dolostones in T2l4 were analysed by polarised thin-sections and cathodoluminescence, major- and trace-element, scanning electron microscope, and carbon, oxygen and strontium isotope analyses. The study results are summarised as follows. (1) The dolostones were mainly precipitated in three stages of <40 °C, 40–60 °C and 60–80 °C, corresponding with three paleodepth ranges of 167–300 m, 433–1000 m and 1067–1433 m. The micritic dolostones and the fabric-retentive dolostones (algal dolostone, granular dolostone) mainly formed in a near-surface–shallow-burial environment, and the crystalline dolostones were mainly formed under intermediate burial conditions. (2) 87Sr/86Sr ratios are equivalent to that of the Middle Triassic seawater, Sr/Ba and V/Ni ratios >1, Na notably higher than that in coexisting limestones of T2l4, and the dolostones always coexist with evaporative minerals such as gypsum, indicating that dolomitisation fluids mainly originated from evaporative concentrated seawater. (3) The dolostones mainly inherit materials from precursor limestones based on trace-element distribution patterns, and carbon and oxygen isotope values that are consistent with coexisting limestones of T2l4. (4) Mediated by micro-organisms during the syngenetic period, micritic dolostones and some algal dolostones were formed by replacing aragonites and calcites. During shallow burial, concentrated seawater rich in Mg2+ from the supratidal–intertidal zone flowed downward owing to gravity along the platform and replaced the underlying carbonate rocks, promoting continuous growth of the early dolomites. In the intermediate burial period, the Mg2+-depleted dolomitisation fluid caused the early micritic and silt-crystalline dolostones to recrystallise into silt- or fine-crystalline dolostones with larger crystals and altered the fabric-retentive dolostones into crystalline dolostones. (5) The evaporative dolostones deposited in the near-surface environment are characterised by maximal enrichment of Fe, Sr and Na, the highest δ18O values, the lowest order degree and the highest Ca/Mg ratios. The reflux dolostones formed in a shallow-burial environment characterised by the lowest Fe, medium δ18O values and the lowest order degree. The burial dolostones that developed in the intermediate burial environment are characterised by relative enrichment of Fe and Mn, minimal Na, the lowest δ18O values, the highest order degree and medium Ca/Mg ratios. The fabric-retentive dolostones mainly formed in a near-surface–shallow-burial environment, and the crystalline dolostones mainly formed under intermediate burial conditions. Dolomitisation fluids mainly originated from the evaporative concentrated seawater, and the dolostones inherit materials from the precursor limestones. Micritic dolostones were formed by evaporative dolomitisation; algal dolostone and granular dolostone were formed by evaporative dolomitisation and reflux dolomitisation; and silt-crystalline dolostone were formed by reflux dolomitisation and burial dolomitisation. [ABSTRACT FROM AUTHOR]

A spark plasma sintering technology has already become rather common for the fabrication of GexSi1-x nanostructured thermoelectric solid solutions. Such trend is related with a number of opportunities and technological tools that enable precise properties manipulation. The present paper is devoted to discussing the modulation of GexSi1-x spark plasma sintering technique that consists in the use of silicon phosphide as a source of n-type doping within the process of sintering. The composition of the sintered powder is investigated. The synthesis of a solid solution was carried out in the process of sintering. The SiP is a chemically stable non-toxic compound that can replace toxic phosphorus in thermoelectric technology thus reducing the safety requirements of the corresponding technology process. The paper investigates the effect of SiP concentration on thermoelectric characteristics. The impurity distribution is analyzed, and the association of phosphorus atoms into clusters at a very high doping level is shown. The distribution of impurity elements was controlled by EMF analysis in a scanning electron microscope. It was shown that sintering of Ge-Si-SiP powder mixture allowed obtaining the phosphorus doped GexSi1-x material with high electron concentration that demonstrate high level of thermoelectric properties. The obtained thermoelectric characteristics are compared with the world's best nanostructured materials [ABSTRACT FROM AUTHOR]

This study investigated the effects of Arabic gum (AG) on the separation performance of polyvinylidene fluoride (PVDF) membranes. The membrane properties were characterized using scanning electron microscope energy dispersive X-ray (SEM–EDX), Fourier transforms infrared (FTIR), tensile strength tester, and contact angle. Results showed that incorporating AG from 0.5 wt% to 1.5 wt% into PVDF membrane could increase pure water flux from 47.46 L/m2 h to 66.04 L/m2 h and porosity from 53% to 58%. Moreover, the highest flux recovery was obtained by PVDF/AG-1.5 membrane, revealing the improvement in fouling resistance against bovine serum albumin (BSA). However, the addition of AG from 0.5 wt% to 1.5 wt% did not affect to increase of membrane mechanical strength and the efficiency of the membranes for BSA rejection. SEM, XRD and FTIR analyses confirmed the successful incorporation of AG, which improved membrane surface hydrophilicity compared to the pristine PVDF membrane. Overall, the obtained result showed that incorporating AG could attain synergy benefits in enhancing the membrane properties and performance. [ABSTRACT FROM AUTHOR]

This paper aims to present compressive stress-strain behaviour and develop relationships for peak stress, strain at peak stress, and material parameter with the modified reinforcing index for analytical modelling of basalt fiber reinforced concretes (BFRC's) stress-strain curves. For this, three different strengths of BFRCs were developed i.e., normal-strength-BFRC, medium-strength-BFRC and high-strength-BFRC, each strength of BFRCs contains 0%, 0.1%, 0.2%, 0.3%, 0.4%, and 0.5% of basalt fibers (BFs). The effect of BFs on mechanical properties, compressive stress-strain behaviour of the BFRCs mixes were studied experimentally. The energy absorption capacity, peak stress, and strain at peak stress of BFRCs have also been studied analytically. Scanning electron microscope analysis was performed to examine microstructural characteristics of BFRCs. The test results indicated that the maximum compressive, flexural, and split tensile strengths and better stress-strain behaviour exhibited at the addition of 0.3% of BFs in all three strengths of BFRCs. Using developed relationships, analytically modelled stress-strain curves closely represented the realistic stress-strain behaviour of BFRCs and fit well with the experimental stress-strain curves. In addition, in literature, the proposed expressions between the material parameter and reinforcing index for analytical modelling of steel FRC's stress-strain curves could not accurately predict the experimental stress-strain curves of BFRCs. [ABSTRACT FROM AUTHOR]

Herbicides based formulations are conventionally used as wettable powder or as Emulsifiable concentrate. The Emulsifiable Concentrates (EC) are prepared by mixing the active content with solvents and surfactants. However, these formulations have undesirable phytotoxic effects due to hazardous solvent and are unsafe to operators during application. Thus, capsule suspension (CS) formulation is considered as an alternative to EC formulations. In this study, we report the preparation of CS formulation of herbicide oxyfluorfen by polymerizing Methylene diphenyldiisocyanate (MDI) and Ethylenediamine (EDA). Water suspensions of the oxyfluorfen microcapsules were prepared by adding anionic, nonionic, polymeric surfactants and formulation auxiliaries. The study also aimed to determine the effect of surfactant on the stability of the microcapsule suspension. It was found that the nature of surfactant influenced the properties of the formulation. The synthesized microcapsules were characterized by Scanning electron microscope (SEM), Fourier Transform Infrared (FTIR) spectroscopy and thermogravimetric analysis (TGA). The microcapsule suspensions were applied on rice crop to establish the safety and its future use instead of oxyfluorfen EC. [ABSTRACT FROM AUTHOR]

The aim of this study was to explore plant-derived peptides as carrier material with the function of anti-hot-melt stickiness of traditional Chinese herbal extracts during spray drying. Crataegi fructus extract (CFE) with a severe hot-melt stickiness problem was used as a model drug, and soy peptides (SPT) were screened as the most effective and suitable carrier material among seven plant-derived proteins and peptides which include soy protein isolate, walnut protein and five kinds of peptides (corn peptides, wheat peptides, walnut peptides, rice peptides and SPT). The addition of 15% SPT also exhibited a strong anti-stickiness effect in other four hot-melt sticky herbal extracts from Chinese herbs (Lycii fructus, Corni fructus, Chaenomelis fructus and Mume fructus) since the obtained powder increased from completely sticking to the wall to more than 50% powder yield. The dynamic surface tensions (DST) of CFE decreased consistently with the increase of SPT from 5% to 20%, and DST1000ms had consistent reduction with the addition of SPT from zero to 20%. Meanwhile, the adhesive force of the single droplet at 28 min decreased below 18.5 N. The softening point of the spray-dried powder of CFE added 15% SPT increased by about 40 °C, and the addition of 15% SPT improved the stability which might be similar with the addition of 50% MD based on scanning electron microscope analysis but more efficiently. These findings confirmed that SPT plant-derived could serve as effective and stable carrier material with good anti-stickiness ability during spray drying. [ABSTRACT FROM AUTHOR]

Denitration is a proven technique that can reduce the nitric acid concentration of high-level liquid waste (HLLW) to meet the aqueous acidity requirement of the TRPO (TriAlkyl Phosphine Oxide) process. However, interfacial crud is generated in the TRPO extraction of the HLLW after denitration. In this work, the interfacial crud was characterized by Fourier-transform infrared spectroscopy and dynamic light scattering. The extraction distribution ratio of zirconium by 30% TRPO in kerosene decreases dramatically after the simulated HLLW is denitrated, and we proposed that the presence of zirconium in the simulated HLLW after denitration is responsible for the generation of interfacial crud. Using ammonium molybdate as a precipitant, the concentration of zirconium in the simulated HLLW was successfully reduced without essentially changing the concentration of other metal ions. The effects of reaction time, temperature, and amount of ammonium molybdate added on the zirconium removal process were investigated and the precipitates formed in the removal of zirconium were characterized by scanning electron microscope, energy dispersive X-ray spectroscopy, and X-ray photoelectron spectroscopy. Finally, after reducing the concentration of zirconium in the simulated HLLW to below 10 mg/L by using ammonium molybdate, the extraction experiment was performed again and no interfacial crud was observed. [ABSTRACT FROM AUTHOR]

Bismuth layer-structured ferroelectric K0.5Bi4.5Ti4O15 crystal was grown by original micro-pulling down method. The scanning electron microscope photos indicate the homogeneous distribution of the four elements of K, Bi, Ti and O in the as-grown crystal. The ferroelectric and dielectric properties were studied and the high Curie Temperature was determined to be 562 °C. Domain structure of K0.5Bi4.5Ti4O15 crystal was investigated by piezoresponse force microscopy (PFM) through ±3 V dc bias. The clear dark and bright contrast in the PFM images indicates the domain switching. [ABSTRACT FROM AUTHOR]

The number of viable spores is the most important quality index of Bacillus-based microbial pesticides. This study aimed to establish a novel pre-treatment method of samples for improving the traditional plate counting method thereby detecting the number of viable spores accurately and reproducibly in Paenibacillus polymyxa-based microbial pesticides. Firstly, three pre-treatment methods of Shaker shaking (SSP), ultrasonic oscillation (UOP), and ultrasonic crushing (UCP) were optimised and compared. The results showed that only the UCP-based plate counting method could detect accurately the viable spore counts (5.2 × 109 CFU/g) in the 5 × 109 CFU/g P. polymyxa original powder, and were repeated well with a coefficient of variation (CV) of 5.0%, compared to SSP (3.46 × 109 CFU/g, CV was 23.4%) and UOP (3.5 × 109 CFU/g, CV was 26.0%). The optimal conditions of UCP were ultrasonic power of 200 W, ultrasonic/intermittent time of 3 s/3 s, and total time of 3 mins (30 cycles). Furthermore, the scanning electron microscope observed that spores were completely desorbed from the carrier by the UCP method. and the average particle size of the carrier pellet was about 2–5 μm, which is significantly smaller than the average particle size of the carrier pellet without pre-treatment (about 15–20 μm) and by the SSP (about 7–12 μm). The plate counting method based on UCP could desorb all spores from the carrier, and the detection results of viable spore counts in P. polymyxa microbial pesticides were accurate and reproducible. [ABSTRACT FROM AUTHOR]

The influences of natural bamboo fibers (BFs) weight fraction on the microstructure, quasi-static and dynamic compressive responses of the epoxy resin matrix composites were investigated with the aid of scanning electron microscope, electronic universal testing machine and the modified Split Hopkinson pressure bar (SHPB) setup. The quasi-static compressive properties of the BFs/epoxy resin matrix composites suggested that the compressive strength were strongly improved with the addition of the natural BFs, which was attributed to the excellent strengthening effect. When the BFs content increased up to 15 wt.%, the compression ratio of the BFs/epoxy resin matrix composites showed 11% reduction than that of the unmodified epoxy resin. Moreover, the stress and strain were linear at the initial part but nonlinear when stress exceeds a certain value. SHPB impact tests results indicated that, compared with the pristine epoxy resin, the natural BFs reinforced epoxy matrix composite with 15 wt.% BFs exhibited the highest dynamic compressive strength, compression modulus and the best strengthening effect. Epoxy resin matrix composites also showed an obvious effect rate effective under impact load. Similar to that in the quasi-static compressive test, the addition of natural BFs has a positive effect in improving the compressive strength of the epoxy matrix. [ABSTRACT FROM AUTHOR]

Natural leather still represents great importance among the materials used by humans in modern times, although it is the oldest-known fiber used by humans. Adding new features to the leather, such as bacteria and fungi resistance, electrical conductivity and magnetic properties, is an ambitious goal for leather developers. In our study, production and characterization of anti-microbial sole leather coated with zinc oxide nanoparticles were achieved. For this purpose, the ZnONPs have been prepared through green synthesis and the prepared nanomaterial loaded on the sole leather by a padding mangle. The surface morphology of the nano coated sole leather was studied using a scanning electron microscope (SEM). Antimicrobial performance of the treated leather to some microorganisms was evaluated by applying the qualitative agar disc diffusion method. The SEM image of the treated leather samples showed successive leather coating, and the nanoparticles completely adhere to the leather surface. The nano-treated leather samples showed significant resistance to the tested bacteria and fungi. Results are promising for the utilization of zinc oxide nanoparticles as additives for sole leather coating. Accordingly, the study succeeded in producing a natural microorganism-resistant sole leather, which can be used in the production of healthy and microorganisms-resistant shoes. [ABSTRACT FROM AUTHOR]

In this study, an attempt is made to check whether a hybrid composite made up of both synthetic and natural fibers (Carbon and Cordia Dichotoma respectively) can be made bio-degradable, at least to some extent, without much compromising on the mechanical properties. Hybrid composites were prepared by reinforcing alkali treated Cordia dichotoma and carbon fibers into epoxy resin using hand lay-up method. By varying the number of layers of fibers in the composite specimen and fixing 20% fiber weight for all composites, nine distinct combinations of specimens were prepared. The maximum tensile strength of 386.68 MPa, flexural strength of 647.08 MPa, and impact energy of 4.82 J were obtained for composites produced with pure carbon fiber, whereas hybrid composite exhibit tensile strength of 367.76 MPa, flexural strength of 646.41MPa and impact energy of 4.74 J. The interfacial bonding between the fibers and matrix of tested specimens was studied using a scanning electron microscope (SEM), as well as the arrangement of fibers within the matrix for the manufactured composite. Thermogravimetric analysis (TGA) was used to investigate thermal stability, and it was found that it was thermally stable up to 415°C. 9. Crystallinity value increases from 20% carbon fiber to 20% alkali fiber. [ABSTRACT FROM AUTHOR]

Treatment of colored wastewater is one of the important challenges of environmental engineers. Adsorption is one of the most efficient methods in dye removal. The aim of this study was to prepare a magnetic adsorbent with Fe3O4 nanoparticles as an inexpensive adsorbent to remove basic violet 16 (BV16) dye from aqueous media. In this experimental study, the effect of parameters such as initial solution pH, adsorbent dose, initial dye concentration, and contact time on the adsorption rate was investigated. The residual dye concentration was read at 545 nm by using a spectrophotometer. Physical, surface, and magnetic properties of the adsorbent were analyzed using Brunauer–Emmett–Teller (BET), Vibrating-Sample Magnetometer (VSM), X-ray Powder Diffraction (XRD), Fourier Transform Infrared Spectroscopy (FTIR), and Scanning electron microscope (SEM) techniques. Adsorption data were described by Langmuir and Freundlich isotherms and reaction kinetics. The results showed that with increasing the contact time and increasing the adsorbent dose, the amount of dye removal by the adsorbent increased and with decreasing the initial concentration of dye, the amount of removal increased. The results also showed that with increasing pH, the removal efficiency of the process increased linearly. According to resuls, the highest BV16 dye adsorption efficiency was 99%, which was obtained at determined values of studied parameters including pH of 7, adsorbent dose: of 0.5 g/L, initial BV16 dye concentration of 25 mg/l, mixing speed of 250 rpm, and contact time of 45 min. Moreover, according to results, removal of BV16 dye using adsorption onto clinoptilolite zeolite magnetized with Fe3O4 nanoparticles obey a second-order kinetic model and Freundlich model (R2>0.99). According to SEM images, the adsorbent surface used is non-uniform and has many pores and also the morphology of the adsorbent surface is preserved after loading of Fe3O4 nanoparticles. According to VSM images, the magnetic saturation in composite is 18.11 emu/g. Results hihlighted the adsorption of BV16 dye onto clinoptilolite zeolite magnetized with Fe3O4 nanoparticles was a useful technique and could provide high efficiency in removal of studied dye from aqueous solutionsl; thus, it mabe be effective and useful in removal other similar pollutants. [ABSTRACT FROM AUTHOR]

In the present work, a specific three-point bending test is applied to evaluate how the roughness can impact the bond strength (adherence) and the mechanism of interfacial failure initiation. The study is conducted using an aluminum alloy 2024-T3 as substrate and the DGEBA (polyepoxide bisphenol A diglycidyl ether) /DETA (diethylenetriamine) as adhesive, considering different abrasive surface treatments. An optimal roughness is reached to maximize the critical force during failure initiation; besides, the roughness impacted the failure propagation mechanism and the failure initiation area for each abrasive treatment. A power-law regression is considered to correlate the critical force and the failure initiation area, considering different average roughness. Local assessment using a mechanical profilometer and Scanning Electron Microscope (SEM) with Focused Ion Beam (FIB) are applied to measure the residual adhesive thickness at failure initiation and failure propagation zones as well as the initiation-to-propagation transitions. It is constated that the residual adhesive thickness is dependent on the average roughness of the substrate. Finally, Weibull's analysis is undertaken to demonstrate that the mechanism of failure initiation for all substrate groups is essentially the same, although the failure propagation mechanism can be different. [ABSTRACT FROM AUTHOR]

Leather making technology is undergoing a profound change from chemical process to enzyme-assisted dehairing. In this work, the SptA protease from halophilic archaeon Natrinema sp. J7 was expressed by Bacillus subtilis SCK6. The crude enzyme extract was applied into enzymatic dehairing process with the enzyme activity of 1800 U/mL. Histologic analysis, scanning electron microscope and wastewater test indicated this SptA protease could serve as a good alternative to sodium sulphide in goatskins dehairing technique. Noteworthily, 8% sodium chloride was introduced in SptA protease dehairing system and achieved a comparable result after 6 h of treatment. This would not only reduce the pollution load significantly, but also bring about 16–20% water-conserving benefit by addressing the issue of high salt in the preservation of hides and skins. In addition, based on bioinformatics, molecular modelling and docking analysis were made as an attempt to illustrate how SptA protease contribute to the loosing and removal of hair from the micro and molecule perspective. It was concluded that this SptA protease could efficiently dehair goatskins without any damage to the grain and collagen structure, ensuring its use as a promising candidate for leather making. [ABSTRACT FROM AUTHOR]

This study investigated the adsorption performance of ibuprofen onto magnetic zeolite clinoptilolite modified with polypyrrole (Clino/Fe3O4/Ppy). The synthesized nanocomposite was characterized by scanning electron microscope, Fourier-transform infrared spectroscopy, Energy-dispersive X-ray analysis, Brunauer-Emmett-Teller, and X-ray powder diffraction analysis. The obtained results demonstrated that the high surface area of zeolite could significantly impact the adsorption process. Various parameters were studied to determine the optimum condition, including contact time, pH, adsorbent dosage, initial ibuprofen concentration, temperature, and mixing speed. The optimization of contact time revealed a high performance in the first 5 min of the adsorption process. Furthermore, when the temperature rose, the efficiency increased as well, with the highest efficiency being achieved at 45°C. Some isotherm models and kinetics equations were used to analyze equilibrium data. The kinetic study revealed that the adsorption process followed pseudo-second-order (R2 = 0.9972), and the isotherm investigations showed that Langmuir (R2 = 0.9941) was an appropriate model for explaining the equilibrium of the adsorption process. Based on the obtained thermodynamic factors, it was represented that the adsorption process was endothermic and spontaneous. Based on the research findings, Clino/Fe3O4/PPy nano-adsorbent developed in this study might be a helpful strategy for removing ibuprofen from various water sources. [ABSTRACT FROM AUTHOR]

Pure and cobalt (Co)-doped zinc oxide (ZnO) nanoparticles were synthesised by co-precipitation method. Various characterisation studies such as powder X-ray diffraction, scanning electron microscope (SEM) and UV-visible spectra were carried out to investigate their structural and optical characteristics. The absorbance spectrum shows the red shift for the Co-doped ZnO nanoparticles and also decrease in their band gap due to increase in dopant concentration. The SEM analysis reveals that the pure ZnO has spherical-shaped morphology and Co-doped samples have hexagonal-shaped nanorods and nanoflowers. Photo catalytic activity of pure and Co-doped Zinc oxide was analysed using Malachite Green and Chrysodine Y dyes under UV irradiation, and it shows good photo catalytic behaviour. [ABSTRACT FROM AUTHOR]

Biomass-derived porous activated carbon and their applications as supercapacitor (SC) electrode materials have gained immense research interest owing to their abundance, inexpensive, recyclable, etc. Herein, we report the synthesis of tea dregs-derived 3D interconnected honeycomb-like porous activated carbon (HCAC) via a simple, effective, and inexpensive method for SC applications. Tea dregs waste was activated using NaOH activation with different mass ratios of 1:3, 1:4, and 1:5 under a N2 atmosphere at 800°C for 3.5 h. The scanning electron microscope, energy dispersive X-ray (EDX) spectroscopy, adsorption/desorption isotherm of N2, X-ray diffraction (XRD), FT-IR, and cyclic voltammetry methods were employed to analyze surface morphology, elemental compositions, specific surface area, crystallographic feature, surface functional groups, and electrochemical behavior, respectively. The as-obtained HCAC-3 has a 3D interconnected honeycomb-like porous architecture with high carbon and oxygen contents, achieved the specific surface area of 624 m2/g, amorphous carbon structure, and containing oxygen functional group. The symmetrical SC devices have an optimum specific capacitance of 100 F/g with an optimum energy density of 13.89 Wh/kg at a power density of 50.05 W/kg. This study could provide a good reference for the synthesis of biomass-derived 3D interconnected HCAC and its applications in energy storage devices systems, catalysts, and adsorbents. [ABSTRACT FROM AUTHOR]

In spite of industries making huge investments, for a viable energy saving, still the methods for conservation of energy are lagging and the industries are still in search for alternatives. The major concern that persists with the oil and gas operations is emission of hydrogen sulfide, frequently or inadvertently, during the initial or later stages of the process. Hence, this study focuses on the indirect electrolysis toward the recovery of sulfur and hydrogen from hydrogen sulfide using graphite as both anode and cathode with calomel as reference electrode. The recovered sulfur was analyzed using high-resolution scanning electron microscope was in range of few microns that was in agreement with the X-ray diffraction analysis confirming the crystalline orthorhombic structure of sulfur (JCPDS Card no.89–2600). The cyclic voltammetry experiment was carried out by sweeping the potential between −1.2 and +1.2 V at a scan rate of 50 mVs−1 obtaining a maximum current density of 0.41 A/cm2. Maximum deposition of sulfur observed at pH 13 with a current density of 0.23 A/cm2 and temperature 80°C. The quantity of sulfur recovered by indirect electrolysis was in the range of 2.9 mg with efficiency of 90.44%.Thus an effective method using indirect electrolysis method was successfully used to achieve crystalline sulfur and hydrogen from H2S. [ABSTRACT FROM AUTHOR]

This work presents the development of polyvinyl chloride/functionalised multi-carbon nanotube (PVC/F-MWCNT) membranes and PVC/graphene oxide (PVC/GO) membranes for the improved removal of chemical oxygen demand (COD) from actual petroleum wastewater. Also, this work for the first time presents the proposed interaction mechanism between the contents of PVC/GO and PVC/F-MWCNT membranes as well as the interaction mechanism of each composite membrane with water molecules. The effect of both F-MWCNT and GO content on the characteristics and performance of the PVC/F-MWCNT membrane and PVC/GO membrane were studied. Fourier-transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), scanning electron microscope (SEM), atomic force microscopy (AFM), contact angle (CA), differential scanning calorimetry (DSC), porosity and tensile strength were used to examine the properties of F-MWCNT, GO, PVC/F-MWCNT and PVC/GO membranes. The composite membranes' performance was studied by measuring the rejection of chemical oxygen demand (COD) and mass flux. It was found that F-MWCNTs and GO played significant roles in the membranes' structural morphology. A significant improvement was obtained in the CA, porosity and tensile strength of the membranes by embedding the PVC casting solution with 0.12 wt% of each F-MWCNTand GO. The PVC/F-MWCNTs membrane showed higher performance in term of mass flux and COD rejection that reached 88.9%, which makes using a PVC/F-MWCNTs membrane preferable to remove COD from petroleum wastewater. [ABSTRACT FROM AUTHOR]

Dysprosium (Dy3+) ion substituted 0.8BaTiO3-0.2Bi0.5K0.5TiO3 (here after abbreviated as BTBKT-20) lead free ceramic materials with composition 0.8BNa0.2(Bi0.5(1-x)Dy0.5xK0.5)TiO3 (where x = 0.01,0.03,0.05) were prepared by conventional solid state reaction method and followed by high energy ball milling process. The X-ray diffraction studies confirm the tetragonal structure of the material at the room temperature. Microstructure studies have been carried out with the help of scanning electron microscope. Temperature and frequency dependent dielectric studies indicate that dielectric constant decreasing with the substitution of Dy3+. The substitution of Dy3+ effect the Curie temperature and it is decreasing with increase of Dy3+ substitution. Relaxor behavior is observed in all the Dy3+ substituted samples. Degree of diffuseness is calculated from the modified Curie-Weiss law and it has been found to be increasing with the substitution of Dy. AC conductivity is calculated and it is found to be obey the universal Jonscher's Power law. [ABSTRACT FROM AUTHOR]

Polyethylene terephthalate (PET) pre-prepared nano/micro fibers were treated by sodium hydroxide (NaOH) aqueous solution and then AgNPs were loaded on them through the soaking process. In total, eight samples were created. Then they were characterized by field emission scanning electron microscopy (FESEM), scanning electron microscopy (SEM), X-ray energy diffraction (EDS) spectroscopy and Fourier transform infrared (FTIR). Disk diffusion and colony counting tests were also performed. Samples containing AgNPs had growth inhibition zones with diameters between 19 and 26 mm while control samples had no inhibition zone. PET microfibers containing AgNPs had a larger inhibition zone on Staphylococcus aureus compared to other samples. The innovation of this research is the placement of AgNPs on the hydrophilic PET micro/nano fibers. [ABSTRACT FROM AUTHOR]

The effect of a barrier layer composed of reduced graphene oxide (rGO) with edge adsorption of K+ (rGOK+) on anticorrosive performance was investigated. Scanning electron microscope (SEM), X-ray photoelectron spectroscopy (XPS), DC polarisation technique and electrochemical impedance spectroscopy (EIS) were used to investigate the morphology, corrosion product, corrosion mechanism and process. XPS results show that the corrosion products are ZnCl2, Zn(OH)2, ZnCO3 and Zn5(OH)8Cl2. SEM, energy-dispersive spectrometer (EDS), polarisation curve and EIS show that the coating with the most rGOK+ not only builds a barrier layer but also improves the utilisation of zinc powder, thereby providing better corrosion protection for the substrate despite the 30% reduction in zinc powder usage. [ABSTRACT FROM AUTHOR]

This research mainly focuses on selecting phase change materials (PCM) and container materials for next-generation concentrated solar power plants (CSP). The present study investigates the hot corrosion behaviour of Inconel 617 and 625 in Na2SO4 + 45 wt-% diatomite PCM environment at 800°C for 40, 80 and 120 h. Oxide scales developed on the alloy surfaces were examined by Scanning electron microscope (SEM) and X-ray diffraction (XRD) to study morphology and oxide phases. The result indicates that Inconel 617 and 625 weight changes were 1.239 and 0.925 mg cm−2 at 800°C for a maximum duration of 120 h. The dense oxide of Cr2O3 is formed on alloys 617 and 625, which gives better oxidation resistance in a PCM environment. Moreover, the Inconel 625 shows lesser weight gain compared to Inconel 617 due to the presence of higher wt-% of Cr in the alloy and Nb formation oxides reducing corrosion species diffusion rate. [ABSTRACT FROM AUTHOR]

The present work aims to evaluate how an innovative and eco-friendly anodizing process with tartaric-sulfuric acid (TSA) bath and a pore widening in an aqueous solution of NaOH 0.1 M can improve the durability in marine environment of co-cured adhesive joints between an aluminum alloy (AA 5083) and fiber (i.e., glass or basalt)-reinforced composite substrates. The aging was carried out by exposing samples to salt-fog spray conditions (5 wt.% NaCl) for 30, 60 and 90 days in a climate chamber, in accordance with ASTM B117. In order to get further insights on the aging behaviour of bonded joints, neat matrix was also exposed to the same environment for 60 days. Quasi-static mechanical tests and morphological analysis through SEM microscope coupled with EDX analyser were carried out to deeper understand how the fracture surfaces change during aging and how this affected the mechanical performances of joints. [ABSTRACT FROM AUTHOR]

In the environment of advocating low-carbon economy, the development of green lighting and the potential application of rare earth luminescent light sources have always attracted much attention. In this study, aiming at the existing defects of white LED, taking the new red rare earth phosphor excited by ultraviolet light as the research object, Eu3+ doped NaLa(WO4)2:0.08Eu3+ phosphors samples were prepared by microwave method. The prepared samples were characterized by x-ray diffraction (XRD), scanning electron microscope (SEM), fluorescence spectrum (PL), CIE color coordinates and other detection methods, and their phase composition, micro-morphology and luminescent properties were characterized. The results show that the doping of Eu3+ does not change the crystal structure of the matrix material, and the NaLa(WO4)2:0.08Eu3+ phosphors is micron-sized and irregular polyhedral at room temperature. It can be excited by ultraviolet light with wavelength of 395 nm to produce red light emission. The color coordinates of NaLa(WO4)2:0.08Eu3+ phosphors are (0.5794, 0.308), and the manufactured device can emit white light with color coordinates of (0.3060, 0.3307). Therefore, the NaLa(WO4)2:0.08Eu3+ red phosphors prepared in this study is expected to be used in the preparation of white LED devices. [ABSTRACT FROM AUTHOR]

Polymer dispersed liquid crystals (PDLCs) are frequently used as a display material owing to their simple design and easily driven characteristics, where the stepwise display effect can be shown through the same electrical switch. In this paper, single-layer PDLCs are laminated into a double-layer structure with an ultra-thin transparent film sandwiched in between, in contrast to single-layer PDLCs. The flat plateau area is clearly exhibited in the photoelectric curve graph, while the step-by-step display is demonstrated experimentally. Electro-optical properties of the composite film as well as its upper and lower layers as a single-layer, respectively, are characterised, by an insignificant increase in threshold voltage (Vth) for the former relative to the latter. In addition, the single-layer film morphology is additionally photographed using a scanning electron microscope. Furthermore, by choosing an ultra-film as a spacer for two PDLC materials, different transmittance regions of the film were obtained, and this result provides a new idea for the realisation of multi-display smart windows at the same voltage. [ABSTRACT FROM AUTHOR]

To investigate the histopathological findings and follow-up outcome of focused ultrasound ablation surgery (FUAS) treatment of multiple fibroadenomas (FA). A total of 20 patients with 101 multiple FAs were enrolled. After one session FUAS ablation, 21 lesions (≥15.0 mm) were surgically removed within one week for histopathological analysis, including 2, 3, 5-triphenyltetrazolium chloride (TTC) staining, H&E staining, nicotinamide adenine dinucleotide (NADH) -flavretin enzyme staining, Transmission electron microscope (TEM) and scanning electron microscope (SEM). The remaining 80 lesions were followed up at 3, 6 and 12 months after treatment. All ablation procedures were performed successfully. Pathologic findings showed that irreversible damage of FA was confirmed. TTC, H&E and NADH staining and TEM/SEM demonstrated tumor cell death and tumor structural destruction at the gross, cellular, and subcellular levels, respectively. The median shrinkage rate at 12 months post-FUAS was 66.4 (43.6, 89.5) %. Histopathological analysis for FAs after FUAS treatment proved that FUAS could effectively induce irreversible coagulative necrosis of FA, and the tumor volume would gradually shrink in follow-up. FUAS was safe and effective to treat multiple FAs with good cosmesis. This study was the first study of detailed histopathological analysis for FAs after FUAS treatment. FUAS can effectively induce irreversible coagulative necrosis of fibroadenoma cells. FUAS ablation of multiple fibroadenomas is safe and effective. [ABSTRACT FROM AUTHOR]

The present study focused on the examination of the seed and pollen morphology of nine native Chinese species of the genus Sorbus L. using Light Microscope (LM) and Scanning Electron Microscope (SEM). The crucial features investigated for seeds include color, shape, epidermal cell size, and seeds coat ornamentation. On the other hand, the pollen grains are analyzed based on quantitative traits as well as the following quantitative traits: polar and equatorial view, shape, apertures and exine ornamentation. Pollens of the studied taxa were monad and trizonocolporate. The most important pollen features include exine ornamentation based on traits of striae and grooves (length and width) and perforations (number and diameter). The variability of the observed morphological features for both seeds and pollen provide important characteristics to differentiate the studied Sorbus species. [ABSTRACT FROM AUTHOR]

Extending the shelf life of fruits without altering their nutritional or sensory characteristics has led to the search for different preservation technologies. Strawberry (Fragaria ananassa) is prone to rapid decay after harvest. Aloe Vera Gel (AVG) provides antioxidants that help prevent rapid ripening; however, its hydrophilic nature can reduce the effectiveness of the coating. On the other hand, Carnauba wax (CWP) could decrease water vapor permeability and has not been previously used for strawberries. The objective of this study was to evaluate the effects of the coating formed by different concentrations of AVG with CWP microparticles. The samples were immersed in the coating for different times, lyophilized and analyzed in the scanning electron microscope, with different resolutions, to establish the experimental conditions and confirmed the formation of the layer on the surface. A Completely Random Design was applied, with a 32 factorial arrangement: AVG (0%, 30%, 45% v/v) and CWP (0%, 0.3%, 0.4% w/v). Three repetitions and 27 experimental runs were carried out. The treatments that presented the best physicochemical and microbiological conditions were analyzed sensorially. The treatments with higher concentrations of the two components provided the least change in weight loss, pH, and ripening index (p ≤.05), and the lowest values of the severity index caused by Botrytis cinerea. The coated samples were well accepted sensorially, with no significant difference with the uncoated strawberries (p >.05). The proposed coatings have the potential to extend the shelf life of strawberries and be applied in the fruit marketing chain. [ABSTRACT FROM AUTHOR]

Corrosion is one of the major issues faced by marine industries. Two of the major metals used in these industries include copper and AISI 5140 steel. This iterates the importance of understanding the microstructure and its influence on the corrosion behavior of these metals in 3.5 wt% NaCl that is studied here. Annealing treatment was performed for both the metals, and the microstructure before and after the annealing treatment was performed using an optical microscope and SEM. X-ray diffraction (XRD) of the metals before and after heat treatment was performed, and it was found that the annealing treatment caused an increase in the crystallite size irrespective of the metal. The samples were subjected to Vicker's microhardness testing, and a decrease in the hardness was achieved post-annealing. The electrochemical studies further proved that there is an improvement in corrosion resistance post-annealing. The kinetic and thermodynamic parameters are described using Arrhenius and transition state theories. [ABSTRACT FROM AUTHOR]

Nanoparticle incorporation in polymeric matrices to generate polymer nanocomposite with the intention of maximizing the "nano-effect" derived from the nanoparticles and minimizing the drawbacks of the polymer is an emerging field of research. In this study, low-density polyethylene (LDPE) was mixed with varying concentrations of montmorillonite (MMT) nanoclays to create a polymer nanocomposite with desirable characteristics. Composite sheets with nanoclays contents of (0, 1, 2, 3, and 4 wt%) were prepared for hardness, tensile-fractography, thermal conductivity, and tensile testing (elongation and stress-at-break). The results showed that, according to scanning electron microscope (SEM) study, LDPE has a low flexibility temperature and is prone to corrosion. For larger MMT filler loadings (>3% wt), tensile-fractography showed nanoclays particle micro-aggregation. The pure LDPE sample fracture's tensile-fractography showed plastic deformation. MMT/LDPE samples with 3% wt hard MMT filler have brittle fractures without appreciable plastic deformation. Thermal conductivity test results show that LDPE/MMT composite thermal conductivity decreased with increasing clay concentration. The thermal conductivity values were reduced from a value of 0.13 W/m.K to a value of 0.039 W/m.K when reinforced with 0% wt to 3% wt filler loading, respectively. With 4% wt filler loading, LDPE/MMT composites had the highest shore hardness at 47.4. Yet, tensile tests indicated that increasing clay content improved the composite's characteristics. At modest loading percentages (1-2 wt%), tensile results were excellent. Furthermore, the elongation at break of the unadulterated LDPE was reduced by 20% and 30% after introducing 1% wt and 2% wt of MMT as reinforcement additives, respectively. Hence, MMT clay can improve the mechanical properties and thermal insulation of LDPE polymer matrix. [ABSTRACT FROM AUTHOR]

Hybrid polymer laminates employed in advanced engineering fields are susceptible to atmospheric conditions, such as moisture and temperature throughout their service life, which may impact their mechanical and damping properties. This research focuses on the influence of three distinct environmental situations: ambient ageing at 25°C, sub-zero ageing at -10°C, and environmental chamber humid ageing at 40°C with 60% RH (relative humidity) on the mechanical and damping characteristics of quasi-isotropic carbon-Kevlar fibre reinforced intraply hybrid composites. Compression molding process was incorporated for the fabrication of the laminates and specimens were aged until the moisture saturation point was reached. The mechanical and vibrational properties of post-aged specimens, including tensile, three-point flexure, short-beam shear strength (SBS), and hammer impact tests, were investigated and compared with pristine specimens. The results showed that the experimental degree of moisture absorption closely followed the Fick's first law, with a greater moisture diffusion rate in the early phase of ageing and moisture saturation in the laminates were ranging from 1.162% to 4.167%. The study also unveiled that diffusion of moisture has a negative impact on the mechanical and vibrational behaviour of the composites. Mechanical strength deterioration was discovered to be highest in the ambient aged specimens followed by humid and sub-zero aged specimens. To evaluate the damage morphology, posttensile test coupons were analysed by employing a Scanning Electron Microscope (SEM). The predominant failure mechanisms found in aged composites were fibre fractures, interfacial degradation due to matrix deterioration, matrix cracks, and delamination. [ABSTRACT FROM AUTHOR]

A Study of the process followed by an Emulsion Polyvinyl Chloride droplet in a spray dryer is necessary to understand the morphology of produced dry powder. For the Production of E-PVC, vinyl chloride monomer turns into liquid under pressure and high temperature. This liquid is extracted into the water in the form of emulsion with the help of an emulsifier, and polymerization is performed using water-soluble catalysts. Investigating the operational parameters of the latex drying process can provide helpful information for the design process. In the present study, a pilot plant of Arvand petrochemical spray dryer with a scale of 1:10 is constructed and studied. The purpose of this study is to experimentally analyze the drying of E-PVC in a pilot-scale spray dryer with a particular focus on determining the effects of drying conditions on the powder properties including morphology. For this purpose, the pilot-scale dryer is constructed, and the impact of various parameters such as inlet air temperature, atomization ratio, and latex concentration on outlet temperature and powder moisture content are investigated. A scanning electron microscope is employed to observe the particle morphology parameters mentioned above. The results showed that the outlet temperature decreased dramatically by increasing the atomization ratio and latex concentration. The results showed that more than 90% of the E-PVC particles are solid spheres. About 6% of donut-like particles, about 3% of particles with pore, less than 1% of broken hollow particles. The SEM image of latex used in experiments with a concentration of 40% and a Class D was taken to determine the shape of the latex particles. The picture showed that the particles were spherical before the drying, so the particles' final deformation is due to spray parameters changes during the drying process. From the morphological viewpoint, the number of agglomerates increased at higher inlet temperatures. More than 84% of particles maintained their spherical shape and have a diameter of 15-20 microns. [ABSTRACT FROM AUTHOR]

Polycrystalline ceramic samples with compositional formula Ba(1-x)PbxTi(1-x) ZrxO3 (x = 0, 0.05, 0.075, 0.10, 0.15, 0.20) were prepared by the conventional solid-state reaction route (SSR). All the samples were sintered at 1300°C for 4 h in closed high-density alumina crucibles with the lead-rich environment. Sintered samples were subjected to X-ray diffraction (XRD) analysis and scanning electron microscope (SEM) for structural analysis. XRD analysis confirmed tetragonal to orthorhombic phase transition for samples with x ≥ 0.10. The relative permittivity and loss were measured as a function of temperature at 1, 10, 100 and 1000 kHz frequencies. The value of relative permittivity at room temperature was found to be increased with an increase in x. PE hysteresis loops were recorded for all the samples (at 30°C and 50 Hz). It was found that the sample with x = 0.05 shows the maximum value of remanent polarization 'Pr' = 18.51 µC/cm2. [ABSTRACT FROM AUTHOR]

Ramie fabrics are suitable for summer clothing due to their excellent moist)ure absorption and breathability. Still, their application in the garment industry is limited by the presence of stiff, coarse hairiness that tends to prickle when it comes into contact with the skin. Herein, a low concentration copper ammonia solution was used to slenderize the fiber of the ramie fabric for a short time at room temperature to eliminate prickle and improve the softness of the fabric. Scanning electron microscope (SEM), Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), and thermal gravity analysis (TG) were used to investigate the morphology and structure of treated ramie fabric. And its softness, smoothness, fiber diameter, breaking strength, air permeability, and moisture absorption were also studied. The results showed that the fibers were slenderized, the stiff, coarse hairiness was reduced, and the softness of the fabric was improved, while its other proper)ties remained good after the ramie fabric was treated under appropriate conditions. The use of copper ammonia solution at room temperature to eliminate the prickle of ramie fabrics was simple and inexpensive, suitable for use in practical production. [ABSTRACT FROM AUTHOR]

This research is a comparative study of untreated and treated date palm fiber (DPF) and kenaf (KF)-reinforced epoxy hybrid composite and explores the properties of DPF. The prepared hybrid composites were characterized in terms of tensile properties, impact properties, physical behavior, water absorption, and thickness swelling. The composites were prepared by hand layup technique. Treated 30% date palm and 70% kenaf (T-3DP7K) showed the highest tensile strength (26.45 MPa) and modulus (4.54 GPa) among untreated and treated hybrid composites. The scanning electron microscope revealed the behavior of fiber and polymers and also the cause of tensile test failure. The impact strength of T-1DP1K revealed highest impact resistant (5493 J/m) among untreated and treated hybrid composites. Remarkably, alkali-treated hybrid composites reduced the water absorption and thickness swelling compared to the untreated composites. In untreated composites, higher DPF content composites showed higher moisture content and dimensional instability. Overall, we concluded that among all hybrid composites, T-3DP7K showed better tensile properties, lowest water absorption, and lowest thickness swelling, and T-7DP3K showed better impact properties. [ABSTRACT FROM AUTHOR]

Creatinine O-phosphate (COP) containing phosphorus and nitrogen elements was used as eco-friendly flame-retardant for lyocell/cotton blended fabric (L/C fabric). The flame retardant fabrics are prepared by a simple and effective dip-dry-cure method. Fourier infrared spectroscopy (FTIR), scanning electron microscope (SEM), and X-ray photoelectron spectroscopy (XPS) analyses certified that COP has been successfully grafted onto the surface of the L/C fabric and distributed evenly. Compared with the control fabric, the thermogravimetric analysis (TG) results showed that the char residue rate of the flame-retardant fabric at 800°C increased by 229% (air atmosphere), indicating that it has excellent char-forming ability. Besides, cone calorimetry results showed that the PHRR and THR values of the treated L/C fabric were reduced by 88.83% and 76.65%, respectively. The volatile pyrolysis products of the treated L/C fabric were determined by thermogravimetric analysis coupled with Fourier transform infrared analysis (TG-IR). In general, these results indicated that the L/C fabric treated with COP had high flame retardancy, excellent washing resistance and thermal stability. [ABSTRACT FROM AUTHOR]

The acrylic acid treated rattan fiber reinforced epoxy (RF/Epoxy) composite has been fabricated by taking various weight percentages (5, 10, 15, 20, and 25 wt%) of fibers using hand layup followed by compression molding technique. The optimum fiber loading has been determined by regression analysis and it is found that 18 wt% of rattan fiber gives maximum tensile strength. The interaction of rattan fiber with epoxy matrix has been studied by Fourier transform infrared spectroscopy and X-ray diffraction. Scanning electron microscope (SEM) has been used to study the morphology of chemically modified rattan fiber and RF/Epoxy composite. The mechanical, thermal, and dynamic mechanical thermal properties of 18 wt% RF/Epoxy composite have been studied as per ASTM standards. From the results, it is observed that RF/Epoxy composite gives best properties at optimum (18 wt %) fiber loading. The maximum tensile strength and flexural strength of the composite are found to be 47.5 and 121 MPa, respectively, which is better in comparison to other natural fiber composites used for manufacturing different automobile body parts. Hence, it can be concluded that 18 wt% RF/Epoxy composite can be considered as a potential candidate for automotive body parts. [ABSTRACT FROM AUTHOR]

This research focuses on developing a new material by reinforcing chemically treated Eleusine Indica (EI) fiber with epoxy resin as matrix. Composites using varying wt% of treated EI fibers were fabricated taking epoxy as matrix. The effect of chemical treatment and fiber loading on various mechanical properties, thermal, and morphology using a scanning electron microscope (SEM) was investigated. From the results obtained, it is obvious that the mechanical and thermal properties of composites reinforced with chemically treated fibers were enhanced due to fiber surface modification which helps in better bonding with matrix. Moreover, the composites with 20 wt% fiber concentration shows good tensile strength, Young’s modulus, impact strength and was found to be 79.31MPa, 3.84 GPa, 32.24 KJ/m² respectively. At this fiber loading the composites were characterized by Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), and thermogravimetric (TGA) and compared with untreated fiber reinforced composites and neat epoxy. Finally, the failure analysis of fracture surface due to delimitation, pull-out of the fibers, percentage of voids, and composite fracture has been verified using scanning electron microscope. The findings provide manufacturers and engineers with a general concept of how to employ the composites to make low-weight automotive parts for improved fuel efficiency. [ABSTRACT FROM AUTHOR]

The aim of the effort is to estimate the effect of jute and bamboo fibers with silica fume (SF) of different proportions on mechanical properties of concrete. Cube, cylinder and prism specimens are tested to determine the compressive, split tensile and flexural strength at 14 and 28 days of curing. To verify the experimental findings, further Artificial Neural Network (ANN) analysis is conducted. The study employs neural network (NN), such as the Neural Network-Leven Berg–Marquardt and the Neural Network Gradient Descent. In this investigation, feed-ahead lower back promulgation neural networks were employed. The NN predicted values are validated with actual values and the variation is found to be within 10% only. The predicted ANN results are compared with existing Response Surface Methodology model. Under compressive, split tensile and flexural load, the broken surface is examined at a smaller-scale level with a scanning electron microscope (SEM). The experimental results show that concrete with 0.5% bamboo fibers and 0.5% jute fibers with 10% SF had higher influence on the mechanical properties of concrete. When comparing ANN results, the suggested ANN model showed high level of accuracy in estimating the mechanical properties of natural-fiber-reinforced concrete. SEM examination displayed the failure pattern of concrete and fibers. [ABSTRACT FROM AUTHOR]

Natural fiber reinforced composites are attracting the attention of industries toward a sustainable and environment-friendly material for the future demands. The main drawback pertaining to the use of natural fiber composites lies in its inferior strength in comparison to its counterpart synthetic fibers. This research focuses on improving the fracture toughness of woven jute fabric mat with different orientations (0°, 30° and 45°) in epoxy resin by incorporating fillers and tested in universal tensile testing machine. Silicon carbide (SiC) particles of three sizes 26 µm, 54 µm and 72 µm were incorporated in the matrix in different weight ratios (5%, 10% and 15%). The fracture toughness of the jute/epoxy composites increases with the increase in the amount of SiC particles up to 10% addition and then it shows decreasing trend with further addition. The fracture toughness values show upward trend when the fiber orientation changed from 0° to 45°. Fractography of the tested specimen captured by scanning electron microscope which reveals the fracture of fibers and micro cracks in the epoxy matrix due to the applied load. Analysis of variance (ANOVA) is also conducted for predicting the most influencing parameters on the fracture toughness. [ABSTRACT FROM AUTHOR]

Synthetic fibers are restricted from being used as reinforcements due to increasing awareness of environmental issues and strict laws from government agencies. In recognition of this, the engineering and scientific communities switched their attention to using natural fibers as reinforcement in polymers to make sustainable composites. The fiber was extracted through the water retting process, and characterized from the stem of the Tithonia diversifolia (TD) plant. Physical, chemical, and mechanical properties were investigated and it was found that this fiber has high cellulose content of 65.33 wt.%, and less wax content of 0.67%. X-ray diffraction (XRD) confirmed the crystallinity index as 45%. Surface morphology was carried out through Scanning Electron Microscope (SEM) analysis. Fourier Transform Infrared Spectroscopy (FTIR) results confirmed the chemical functional groups. Thermogravimetric Analysis (TGA), TG and DTG curves were used to evaluate the fiber thermal stability. This result confirms that TD fiber can be used as potential fiber reinforcement in biocomposites. [ABSTRACT FROM AUTHOR]

The current study investigated the use of polyester synthetic (PES) fiber and basalt (BS) and bagasse (BG) natural fibers on the strength and mechanical behavior of sandy soil in pavement construction projects. A series of California bearing ratio (CBR) and indirect tensile strength (ITS) tests were performed on fiber contents (FC) of 0.5,1 and 2% and fiber lengths (FL) of 2.5, 5, and 7.5 mm. Findings show that the maximum California bearing ratio (by increasing 3.3 times) and indirect tensile strength (by increasing 2.98 times) are obtained in the length of 7.5 mm and the content of 2% for polyester and basalt fibers, respectively, which is also evident in the scanning electron microscope (SEM) test results. Also, based on the analysis of variance (ANOVA) and according to various factors including P-value (<0.05), it was determined that the contrast between the values is statistically significant. Due to California bearing ratio – indirect tensile strength and California bearing ratio – resilient modulus experimental relationships, the relationship between resilient modulus-indirect tensile strength was provided with very good correlation coefficients. Furthermore, sensitivity analysis revealed that California bearing ratio and indirect tensile strength values are noticeably influenced by fiber content variations. [ABSTRACT FROM AUTHOR]

The research is aimed to understand the effect of WC/C coating on the bearing rolling elements to improve fatigue life in surface distress conditions. The 1–1.5 microns optimized coating thickness was deposited on the steel substrate using the PVD process. The coating's physical and chemical properties were analysed by X-ray diffraction, scanning electron microscope, contact profilometer, nanoindentation hardness, and micro scratch indenter. The wear properties were compared on a ball-on-disc tribometer with and without a coated specimen. The bearing tests were performed in contaminated and clean lubrication conditions to prove the coating's effect on bearing life in surface distress conditions. Results show that coated roller bearings perform at least two times that of the standard bearing. The overall benefit of less friction and wear resistance was due to the polishing action and coating transfer mechanism of multi-layer coating which increases oil film thickness between contacts and hence improve bearing life. [ABSTRACT FROM AUTHOR]

In this work, the packed thickness of pyrite's effect on its conversion behavior and kinetics was investigated under air in high temperatures. The results showed that pyrite was oxidized to hematite directly with no more than 2 mm packed thickness, or indirect oxidation occurred (pyrite → pyrrhotite → hematite) when greater than 2 mm. Subsequently, the evolutions of pyrite were studied comprehensively by X-ray diffraction (XRD), Raman, Scanning electron microscope (SEM), and Transmission electron microscopy (TEM). The kinetics by the Avrami – Erofeev method displayed that the activation energy of the process of pyrite → hematite (27 KJ·mol−1) < pyrite → pyrrhotite (34 KJ·mol−1) < pyrrhotite → hematite (42 KJ·mol−1). The thinner-packed pyrite requires less energy to oxidize and more readily undergoes direct oxidation. The thermodynamics theoretically explained the reasons for indirect/direct oxidation of thicker-packed/thinner-packed pyrite that ΔGpyrrhotite < ΔGhematite in the thicker packed, or ΔGpyrrhotite > ΔGhematite in the thinner packed. This paper provided some fundamental and significant knowledge of pyrite oxidation to reduce SO2 emissions and industrial production safety. [ABSTRACT FROM AUTHOR]