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The current research studies the effectiveness of steel fibrous layers on the performance of self-compacting lightweight reinforced concrete two-way slabs with (length/width) ratio ≈ 1.618 (golden ratio). In this work, steel fibers (SFs) have been added to four slab specimens with volume fractions of 0.4 % and 0.8 %, in one bottom layer and two top and bottom layers, in addition to a reference slab without SFs, the four slabs were tested under uniform load. The results revealed that when using single or dual fibrous layers, the flexural strength of slabs was considerably enlarged (numerically 41.3 % for single bottom layer and 72.4 % for both top and bottom layers when using 0.4 % SF, and 113.7 % for a single bottom layer and 193 % for both top and bottom layers when using 0.8 % SF) as compared with nonfibrous slabs, and the failure mode had altered from flexure mode to shear one as compared with nonfibrous slabs. The effect of these fibrous layers was enlarged with increasing the content of SF. And for the same amount of SF, the influence of SF is greater when it is distributed in one bottom layer (numerically 113.7 %) than when distributed in two layers (numerically 41.3 %).

This experimental investigation describes an extensive series of reduced laboratory scale tests, conducted on circular and ring footing models rested on a geogrid reinforced cohesionless soil. The study examined the impact of several factors at different relative sand densities, such as the inner to the outer diameter ratio of the ring footing, the number of geogrid reinforcements, the depth of the initial reinforcement, and the vertical spacing between the geogrids, as well as the geogrid stiffness. The results indicated that the optimum diameter ratio of ring footings resting on loose or medium-dense cohesionless soil is 0.40 at which the maximum bearing capacity is reached, leading in a cost-effective design of the footings, while for the dense soil, a diameter ratio of 0.45 is the optimal ratio. Also, the results indicated that the optimum number of reinforcement layers which after the bearing capacity improvement can be considered negligible is three layers for the circular footing and four layers for the ring footing model. To achieve the maximum increase in bearing capacity, the study identifies optimal values for the depth of the first geogrid reinforcement layer and the vertical spacing between reinforcements, which apply to circular and ring footing. While the stiffness of the reinforcement has a significant effect on the bearing capacity, this effect is not proportional.

The purpose of this paper is to establish the existence and uniqueness of solutions to impulsive stochastic Volterra integral equations driven by Lévy process (ISVIEs, in short). By employing the averaging method, we propose a simplified form for ISVIEs. Moreover, we prove that the solutions of ISVIEs can be approximated by the solutions of the simplified one without impulses in the sense of mean square and in probability. Finally, two examples are presented to illustrate the theoretical results.

Vertically aligned Al-doped ZnO nanorods (AZO-NRs) were grown on glass substrate using a chemical bath deposition (CBD) method at various temperatures between 80°C and 130°C. The results showed the Al content in the AZO-NRs strongly depends on the growth temperature. The optimum doping level was attained at 110°C. The morphology was maintained in each sample, and the lasing properties were investigated against the Al-doped variation. The sample with a high doping level exhibited superior random lasing, with high intensity and spectral width of less than 0.08 nm. The same sample also had the lowest pumping threshold of 0.192 mW. More importantly, this study showed the possibility of utilizing doping as a tuning parameter for random lasing, whereby a 7.3 nm redshift in the lasing peak was observed with increasing doping concentration. This study also placed an emphasis on AZO-NRs as potential candidates for tunable random laser devices.

The green synthesis of metal nanoparticles (NPs) using plant derivatives and microbial organisms has emerged as a significant avenue for sustainable materials science. This review provides an overview of eco-friendly methods for synthesizing metal NPs, particularly emphasizing their synthesis from plant biomass using rapid and environmentally friendly approaches. The variation in reduction mechanisms among different plant species, an underexplored aspect, is thoroughly discussed. The review highlights the diverse applications of green-synthesized metal NPs in biomedicine, particularly their exceptional antimicrobial and antioxidant properties, rendering them attractive for wastewater treatment – an area of increasing interest. It covers various synthesis and characterization routes, and functional properties of metal NPs, along with presenting successful proof-of-concept examples. A fundamental exploration of their physical morphology is provided, contributing to a multidisciplinary approach to environmental research. The review also sheds light on current trends in water treatment techniques, with a specific focus on the application of NPs synthesized through green methods, aligning with the broader aim to understand and address environmental challenges more holistically. Given the limited data and growing industrial demand for plant-mediated metal NPs, this review aims to inspire readers from diverse disciplines to explore the potential of naturally synthesized NPs and their expanding applications, contributing to the advancement of sustainable materials science.

Purpose: To describe the clinical findings and outcomes in patients who presented with uveitis associated with multiple sclerosis.Methods: Retrospective review of 20 patients (38 eyes).Results: The most frequent ocular finding was multifocal elongated retinal perivenous “sheathing” with focal vascular leakage on fundus fluorescein angiography in 29 eyes followed by vitreous snowballs and debris in 26 eyes, anterior chamber inflammation in 15 eyes, mutton-fat keratic precipitates in 14 eyes, posterior synechiae in 13 eyes, cystoid macular edema in 9 eyes, iris nodules in 4 eyes, and optic neuritis in 3 eyes. Patients with cystoid macular edema were treated successfully with systemic corticosteroids combined with mycophenolate mofetil. Ocular complications were cataract in 6 eyes, glaucoma in 2 eyes and vitreous hemorrhage in 1 eye.Conclusions: Multifocal elongated retinal perivenous “sheathing” with focal vascular leakage on fundus fluorescein angiography is the most frequent finding in uveitis associated with multiple sclerosis.

Li-rich layer-structured cathode thin films have been successfully synthesized by combustion technique and deposited by Pulsed Laser Deposition (PLD) technique to produce LCNAO Ferrimagnetism. Pulsed Nd-YAG laser with wavelength (λ=532nm) was used and for (10 ns) and energy influence (1.4 J/cm2) at different substrate temperatures (100, 200, 300) °C and O2 pressure at 10 mbar. The structure, morphology, and magnetic properties of the films were determined by XRD, FESEM, SEM, and VSM. The results, Li rich layered structure at peak (003), very smooth surface without any pinholes or cracks. The film’s cross-section view on the Si substrate was used to estimate the film thickness, which was about 63.83 nm. Better crystalline features and spherical shape, average particle size of (1-12) nm could be obtained at substrate temperature of 200 °C. The result obtained at Ms (0.695) emug-1 of powder larger than LCNAO thin film (0.147) emug-1 about 5 times with natural soft loop has emerged with a very small coercive field. The equivalent circuits of the thin film was determined by EIS at substrate temperature (100) °C,with double layer capacitance, high surface area and indicated configuration of equivalent circuits and their symbols (CR(CR)(CR)(CR)) with no defects.

AbstractLet R be a ring with identity and S be a unitary left module over R. In this paper, we give the concepts of semismall compressible and semismall retractable modules. Also, we study properties of semismall compressible and semismall retractable modules, Also, we assert that the semismall compressible modules property is inherited by direct summands.

Mesoporous silicon (mesoPSi) layers fabricated by the photoelectrochemical etching (PECE) method in hydrofluoric acid (HF) are active as carbon monoxide gas sensors. The modified porous silicon (PSi) can be used with noble metals to manufacture an effective gas sensor. Embedded gold, platinum, and palladium nanoparticles Au, Pt, and Pd-NPs could modify the surface morphology of mesoPSi and form mesoPSi/AuPtPd-NPs hybrid structures through a simple and dipping process in fixed salt concentrations. The morphology of the hybrid structures has been studied using scanning electron microscopy and X-ray diffraction. The prepared gas sensor has measured the electrical characteristics at room temperature. Shape, nanoparticle size, and specific surface area strongly influenced the current–voltage characteristics. The results show that Au, Pd, and Pt-NPs sizes prepared by the dipping process for mesopore-like structures were in the range from 0.64 to 7.53 nm. Besides, considerable improvements in the response, recovery times and sensitivity of gas sensor were noticed when decreasing the incorporated Au, Pd, and Pt-NPs to the mesoPSi matrix.

This research concentrates on evaluating the effect of using two new techniques for strengthening steel beams with carbon fiber–reinforced polymer (CFRP) strips on the structural behavior of these beams at service and ultimate load stages by using a confining steel plate in two different configurations. Five steel beams with lengths of 1,500 mm were tested under a single concentrated load at midspan: the first (nonstrengthened) beam was used as a reference beam, the second beam was strengthened by only a CFRP strip located at the bottom flange (tension face), and the third beam was strengthened by only a steel plate, which is also located at the bottom flange. The first technique is represented in the fourth beam, which was strengthened by a CFRP strip confined by a steel plate welded at its ends, whereas the second technique is obtained by an amendment done on the first technique and is represented by the fifth beam, which was strengthened by a CFRP strip with the confining steel plate (welded at its ends) and glued with the CFRP strip by a suitable epoxy adhesive. Test results have shown that the first technique has led to less deflection, less tensile strain, and a higher yield load at the service load stage (i.e., elastic region), whereas the second modified technique has led to a further decrease in deflection and tensile strain and an additional increase in yield and ultimate loads, and both of those outcomes were higher than the algebraic sum of the increases resulting from beams strengthened by a “steel plate” and “CFRP strip” individually.

•Overview of current research on the synthesis of Fe3O4nanoparticles was articulated.•Organic and inorganic materials have been successfully modified the Fe3O4surface.•Bi-layer and multilayer methods of Fe3O4/Au and Fe3O4/ʽglueʼ/Au have been analyzed.•Medical applications of Fe3O4and Fe3O4/Au have been itemized.

Platinum nanoparticles (Pt NPs) have attracted interest in catalysis and biomedical applications due to their unique structural, optical, and catalytic properties. However, the conventional synthesis of Pt NPs using the chemical and physical methods is constrained by the use of harmful and costly chemicals, intricate preparation requirement, and high energy utilization. Hence, this review emphasizes on the green synthesis of Pt NPs using plant extracts as an alternative approach due to its simplicity, convenience, inexpensiveness, easy scalability, low energy requirement, environmental friendliness, and minimum usage of hazardous materials and maximized efficiency of the synthesis process. The underlying complex processes that cover the green synthesis (biosynthesis) of Pt NPs were reviewed. This review affirms the effects of different critical parameters (pH, reaction temperature, reaction time, and biomass dosage) on the size and shape of the synthesized Pt NPs. For instance, the average particle size of Pt NPs was reported to decrease with increasing pH, reaction temperature, and concentration of plant extract.

Soil stabilization is a well-known methods for the treatment problematic soils. Its advantages over soil replacement include low cost and fast implementation. The alkaline activation of soft soils is a new technique that has been proposed recently to stabilize soft soils. However, its strengthening mechanism and the final product in terms of stiffness and brittleness resemble those observed in cemented soils. In other words, the residual strength which emerges when approaching failure is very low, and this results in immediate damage to building structures. These shortcomings need to be overcome, particularly in places where seismic loading can be expected. In the case of cemented columns under heavy embankments, horizontal displacement is likely to occur under seismic loading. This will result in the failure of stabilized material due to frail bending moments, making greater residual strengths more important than higher peak strengths. To address this problem, a fix fly ash content of 40% and polypropylene fibers in the range of 0.5%, 0.75%, 1%, and 1.25% were considered. Compressive, flexural and indirect tensile strength test results revealed the feasibility of polypropylene fibers to improve post-peak behavior, thus allowing for higher residual strength after failure.

Regarding the significance of binder quantity, alkali activator molarities, and thermal curing, this work was utilized to geopolymerize with a potassium-based alkaline activator to strengthen soils. Five different molarities of palm oil fuel ash (POFA) in four different amounts were utilized to activate the clayey soil. POFA admixtures have been used to test soils. The results showed that for mixtures with 10 and 12.5 molarities, the unconfined compressive strength (UCS) with 15 % and 20 % of POFA was stronger. Comparing the strengths of the blends with various POFA amounts and concentration molarities allowed for this determination. To increase the strength, it is crucial to consider how the geopolymerization method's temperature and curing time affect the UCS of the soil-POFA mixture with and without fibers. The UCS of the treated soil mixtures was changed by heating at 30, 50, 70, and 90 °C. The outcomes demonstrate that increasing the curing temperature will hasten the alkaline activation process. After seven days of heating, the treated soil specimens with and without fibers exhibit the best mechanical properties at a healing temperature of about 70 °C, with compressive strengths of 16.7 and 11.4 MPa. The interaction between the geo-polymeric matrix and the fiber surface, the molarities of the alkaline solution, and the heating temperature were the most important aspects, according to an investigation of the microstructures, in improving the behavior of the reinforced mixes. By offering an efficient approach for increasing the qualities of soil treated by the alkali activation of POFA through the inclusion of glass fibers with adequate molarities of reagent and cure heating temperature, the current work offers new insights into soil stabilization operations. This has advantages over conventional calcium-based binders due to their emission of carbon dioxide during manufacture, which is one of the major causes of global warming.

This paper presents the role of clay portion in soil used to stabilize soils during alkaline activation with potassium-based alkaline activator. A 10 M potassium hydroxide solution was utilized to activate the soils with and without palm oil fuel ash (POFA) at a solution. Soils with and without POFA mixtures were tested using unconfined compression tests and microstructural analysis (using scanning electron microscopy and X-ray diffraction). Comparing the strength of the mixtures with and without POFA, the results presented that short-term compressive strength was higher for mixtures with POFA. However, after longer curing the admixtures of higher kaolinite content with POFA reached significantly higher strength levels than the admixtures without POFA. This work brings new insights to the soil stabilization by alkaline activation providing a relatively new avenue for effective utilization of aluminosilicate source materials with parent-treated soils. The clay minerals of hosted soil play an important role in soil stabilization with alkaline activation that affects the behavior of binder with hosted soil.

The stress-strain state of a plastic layer under compression by two rigid parallel rough plates under conditions of plane deformation is investigated. The hypothesis of flat sections is used. Tangential stresses are found in the part of the layer under load, as an approximate solution of the system of equations of the stress-strain state of the compressible layer. The solution is obtained in analytical form. On this basis the velocities of the points of the layer are calculated in the analytic form. The size and shape of the free surface are calculated depending on the thickness of the layer. The coefficients of this dependence are determined by recurrent relations. On this basis, an algorithm for finding the shape of a free surface is found. The computational experiments are provided and the results are compared with results obtained with FEM and ANSYS.

Platinum nanoparticles (Pt NPs) were synthesized, through sonochemical and conventional methods, using the extract from Prosopis farcta fruits (PFFs) as a reducing agent and stabilizer. The structure, morphology and colloidal stability of Pt NPs synthesized by both methods were characterized and compared. A Vibra-Cell ultrasonic solid horn with tip size, frequency, a power output of 12inch, 20 kHz and 750 watts, respectively, were used in the sonochemical synthesis of Pt NPs for 30 min. The formation of amorphous or crystalline Pt NPs is attributed to rapid heating/cooling cycles of the cavitation microbubbles generated by the sonication. The purity, uniformity and crystallinity of Pt NPs synthesized by the sonochemical method were shown to be better than those obtained from the conventional method. The Pt NPs also exhibited smaller particle size with higher colloidal stability and hydrodynamic size. The results confirm that the irradiation power of the sonochemical method enhances the crystalline properties of nanoparticles and hinders their agglomeration. Therefore, the sonochemical method can synthesize Pt NPs with better physicochemical properties compared to conventional methods.

This study is the first report on the usage of fresh fruiting bodies of Enoki mushroom (Flammulina velutipes) as a new green reducer agent incorporated in the mycosynthesis of gold nanoparticles. The mycosynthesized AuNP was characterized for its physical and chemical properties using optical observation, UV–vis spectrometer, FESEM, AFM, DLS, XRD, Zeta Potential, and FTIR analyses. The optimized AuNPs were then tested for its efficacy in the decolorization of Methylene Blue (MB). The purple color of AuNPs indicates that the solution contains a mixture of triangular, spherical, and irregular shapes with an average of size 74.32 nm. The pattern of XRD clearly showed that the formed AuNPs were crystalline while DLS and Zeta Potential data showed that mycosynthesized AuNPs exhibited good stability and aggregation properties in colloidal form. FTIR showed the attachments of polysaccharides, amino acids and phenol as reducer agents on AuNPs. The efficacy test exhibited that the degradation of MB increased with the increase of the incubation time in presence of AuNPs. The proof-of-concept that mycosynthesized AuNPs by fungal natural organic materials of Flammulina velutipescan act as catalysts in reducing the MB dye is proven by the best decolorization of MB at 75.35 % after 4 h soak.

Let ? be a ring with identity and let T be a unitary left Module over ?. In this paper, we give some cases when a direct sum of hollow Modules is semihollow-lifting, Also; we give a condition under which a direct sum of two Modules is semihollow-lifting,

•A rapid myco-reduction of chloroauric acid to gold nanoparticles using aqueous extract of fresh shiitake mushroom.•Synthesis of AuNPs was confirmed by UV–vis, FE-SEM, AFM, Zetasizer, Zeta Potential, XRD, EDX, and FTIR analyses.•The AuNPs exhibited triangular, hexagonal, spherical and irregular shapes with an average of sizes reached 72 nm.