Bulletin of Materials Science最新文献

Accumulation of water in large diesel storage tanks due to climatic differences poses significant operational challenges, including potential contamination of tanker deliveries and the growth of harmful microbes leading to filter blockages and vehicle malfunctions. To mitigate this issue, we focus on the synthesis of biodegradable surfactants capable of emulsifying free water to form stable emulsions. Among various classes of biodegradable surfactants tested, oleic acid diethanolamide emerged as a promising candidate due to its superior emulsifying properties and relatively unexplored potential. To assess the maximum water emulsification, oleic acid diethanolamide was synthesised by optimising the ratio of oleic acid to diethanolamine. Out of the prepared formulations, a clear emulsion was achieved at a 1:1 ratio of oleic acid to diethanolamine, demonstrating higher efficacy in water emulsification compared to other formulations. Characterization analyses, including FTIR and total acid number, were conducted for all surfactants. Formulations utilising the synthesised surfactant at varying concentrations, ranging from 1 to 10% were used to stabilise 5% water in the emulsions. The study demonstrated that clear emulsions showed extended stability beyond 45 days with formulations having surfactant concentrations ranging from 6 to 10%. The emulsions were further characterized for key fuel properties such as calorific value, viscosity and cloud point to meet the operational requirements of the fuel. The research aims to provide a sustainable, environment friendly and operationally efficient solution to the persistent problem of water precipitation in large diesel storage tanks, offering operational efficiency and environmental benefits to the fuel industry.

In engineering projects involving expansive clay, its mechanical and chemical properties are enhanced through soil stabilization using various admixtures such as fly ash, lime, and cement. Considering the admixture’s limitation in recent years, the employment of waste materials in stabilizing such soils is highly encouraged. This study investigates the efficacy of digestate ash as a soil stabilizer under diverse temperature conditions (100°C to 800°C) through an unconfined compressive strength test at an optimal stabilizer content. The Atterberg’s limits and compressive strength test were performed on the clay with and without additives at room temperature through various curing times (0 and 28 days). The digestate ash was used at 0 to 25% (by dry clay weight) as an additive along with the initial consumption of lime as an activator at 4.5% (by dry soil weight). The maximum unconfined compressive strength value of 336 kPa was observed when using 15% digestate ash obtained at 560°C for a curing period of 28-days. The significant alteration in mineralogical and chemical composition was identified when the DA-modified clay underwent X-ray diffraction and fourier transform infrared examinations. This research facilitates better understanding of digestate ash-based soil stabilization in different thermal conditions, aiding sustainable soil improvement in civil engineering and environmental remediation.

A nano-sized Al₂O₃/MGO composite was studied for its ability to activate peroxymonosulphate (PMS) and generate active radicals for the degradation of ciprofloxacin (CIP). Degradation tests were performed at pH 7 with a CIP concentration of 20 mg × l⁻¹, the Al₂O₃/MGO dose of 2.0 g·l⁻¹, and the PMS dose of 2.0 g·l⁻¹. In addition, the degradation of CIP and the stability of the Al₂O₃/MGO-activated-PMS system were consistent after three repeated experiments. Furthermore, sulphate radicals (({text{SO}}_{4}^{ - bullet})) and hydroxyl radicals ((^{bullet})OH) were detected during the degradation of CIP, leading to the formation of nine degradation intermediates. Additionally, two possible degradation pathways were proposed. The results of this study suggests a new mechanism for the degradation of CIP in Al₂O₃/MGO-activated-PMS system, which could be applied to sulphate radicals (({text{SO}}_{4}^{ - bullet})) advanced oxidation processes (SR-AOPs).

In order to further improve the corrosion resistance of 316L stainless steel, which is commonly used in petrochemical enterprises, this paper leverages the characteristics of electrochemical deposition, utilizing pulsed-assisted jet electrodeposition technology. The morphology, hardness, wear resistance and corrosion resistance of the Ni-SiC composite coatings were investigated using scanning electron microscopy, X-ray diffractometer, energy-dispersive spectroscopy, a Vickers hardness tester, a friction and wear tester and an electrochemical workstation. The results indicate that deposition temperature influences coating properties more significantly than other factors. At a deposition temperature of 40°C, the coating exhibits minimal surface defects and the highest SiC particle content. At this time, the microhardness of the composite coatings reaches 652.85 HV, which is increased by 113.75% compared with the substrate, and the minima of the average friction coefficient and the average wear width are 0.73 and 383.6 μm, respectively, which are 4.13 and 40% lower than those of the substrate. In addition, the corrosion current density and annual corrosion rate of the composite coatings were reduced by 67.01 and 67.13%, respectively, compared to the substrate at this temperature. The study indicates that variations in deposition temperature significantly influence the wear and corrosion resistance of nickel-based composite coatings.

NiO were prepared by hydrothermal method using nitrate hexahydrate and urea as precursors at 100°C for 12 h. The morphology, size and structure was observed by scanning electron microscope and X-ray diffraction (XRD). The gas sensitivity of NiO to ethanol vapor was characterized by CGS-8 gas sensing analysis system. The results showed that the sensitivity of NiO-based gas sensor increased from 1.82 to 3.25 under the additive of polyvinylidene fluoride (PVDF). The mechanism of the enhanced gas sensing performance was investigated.

Conductive scaffolds are gaining increasing attention in peripheral nerve repair for their good biocompatibility and electrical properties similar to those of normal nerves. In this study, silk fibroin (SF) nanofibre mats coated with polypyrrole (PPy) were prepared through electrospinning and chemical polymerization. Scanning electron microscopy (SEM) showed even and firm coating of PPy around the nanofibres, and fourier transform infrared spectroscopy (FTIR) analyses of the conductive mats confirmed the presence of hydrogen bonds or electrostatic interactions between PPy and SF. The conductivity of the composite mats could be regulated by varying the pyrrole monomer concentration from 10–20 mM, resulting in corresponding changes in conductivity from 9.4 ± 3.4 × 10^–5 to 4.6 ± 1.0 × 10^–3 S cm^–1. The mechanical strength, hydrophilicity and biodegradability of the mats exhibited similar changing trends. Biodegradability tests showed weight losses of 51.2, 13.6, 11.2 and 15.1% for composite mats with varying PPy coating rates on the 28th day, revealing that the biodegradability can be regulated and optimised by varying the pyrrole concentration. Schwann cell culture confirmed that the SF/PPy mats improved cell proliferation and adhesion compared to pure SF mats. The results demonstrate that the SF/PPy mats, with nanoscale surface, excellent biocompatibility, conductivity and controllable biodegradability, represent promising materials with potential for use in peripheral nerve regeneration.

Graphical Abstract

In this study, we investigate a simple technique in surface-enhanced Raman spectroscopy (SERS) substrate fabrication designed to decrease synthesis time, effort and cost. Sputtering is utilized to deposit a gold (Au) layer on insulating substrates, and annealing treatments are applied to agglomerate the Au atoms into the sought-after nanostructures conducive to the SERS effect. The samples are characterized by scanning electron microscopy, Raman spectroscopy, atomic force microscopy, etc. This study shows that with increasing sputtering amperage and time, the film thickness increases, and with increased annealing temperature, the surface roughness decreases while increasing the particle-to-particle distance. A quartz substrate with 10 mA current, 40 s time and annealing at 300°C produced the highest enhancement factor. Through the utilization of sputter coating and a simple annealing step, the complexity of SERS substrate synthesis can be scaled back considerably, allowing further utilization within industrial and medical settings and unlocking more potential for SERS.

Stretchable conducting polymer nanocomposites are indispensable for designing flexible electronic devices mainly employed in emerging robotic technology to improve human–machine interactions. Herein, we report the fabrication and testing of 300% stretchable electronic film resistors as strain sensors by spray coating carbon nanofibers (CNFs)/natural rubber solutions over a stretchable acrylic latex-CNF nanocomposite substrate. The CNF-based coatings had a low sheet resistance of 26 Ω sq⁻¹ and very good current transmission behaviour under elongation. Under 300% elongation, the nanocomposite film current reached ~55 µA demonstrating their potential as flexible thin conductive films.

Zn₃V₂O₈ (or ZVO) nanophosphor was prepared using a simple solution-combustion technique and sintered at 700–800°C for 5 h. The effects of additive and sintering temperatures on structural, morphological and optical properties have been investigated. The structural studies revealed an orthorhombic phase structure. The d-spacing and lattice constants also increased with the sintering temperature. The microplate-shaped morphology of ZVO sintered at 750°C is confirmed by SEM and TEM pictures, with an average grain size of roughly 3–5 μm. The optical energy gap of the direct transition is also estimated, and it decreases from 3.4 to 3.1 eV with the increase in sintering temperature. The ZVO also demonstrated a broad photoluminescence (PL) emission range between 450 and 600 nm, with a peak at 534 nm, indicating green luminescent emission. Large grains with microplate shapes emit the highest PL intensity in ZVO phosphor at 750°C.

Environmental toxicants can impact brain health and function. Studying their effects on the rodent brain is paramount to understanding the mechanisms and devising therapies. The stereotaxic device is widely used to target brain regions. However, the cost of this device is very high and cannot be afforded by researchers from low- and low-middle-income countries. This study has modelled, designed, fabricated, and evaluated a cost-effective stereotaxic device. A 3-D model of the stereotaxic device was prepared using FUSION 360 software followed by fabrication using aluminium and steel. The aluminium has malleability, lightweight, high extrudability, and corrosion resistance property, making it the material of choice for fabricating the nose clamp, mouth restrainer, and ear bar. To construct the parts requiring motion, we used alloy steel, which has high density, tensile strength and smooth texture. To achieve better accuracy, computer numerical control (CNC) and an automatic wire-cutting (EDM) manufacturing processes were used in fabrication. Later, the dye microinjection and electrolytic lesion techniques were used to validate this instrument. A comparison of percent accuracy for hitting structures between the fabricated and commercial stereotaxic devices for both the deep and superficial brain structures such as the substantia nigra (91.7 vs. 92.5%), thalamus (92.6 vs. 98.22%) and hippocampus (92.85 vs. 98.75%), showcased comparable accuracies between devices. The cost of the materials used were approximately nine thousand Indian rupees, and the labour charges for different machining processes used were approximately seventeen thousand Indian rupees. Totalling to 26,000 Indian rupees or 310 US dollars. This cost may vary depending on the material type/vendor as well. The materials can be provided to a workshop, and the design reported here can be used to make a stereotaxic device for rodent research. The 3-D modeling approach presented here coupled with computerised numerical control/electronic discharge machining process achieves high precision comparable to a commercial product and is also affordable. This study will enable students/researchers in middle and low-income countries to perform neuroscience/toxicological studies on the brain using this self-made low-cost precision device.