Table of Content

Open Access Research Article

Dirac's Spectrum from Newton’s Laws in Graphene

Received: 17 March 2020;  Published: 01 July 2020;  doi: 10.21926/rpm.2003016

Abstract

The present report provides a phenomenological theory for monolayer graphene, in which two worlds, the quantum and the classical, meet and complete each other in the most natural manner. In the present report, electron mass-vortex representation is introduced, and the surface tension excitation states in the monolayer graphene are defined. The band-mass of the electrons at the Dirac’s point was calculated through the mathematical introduction of a mass-dispersion relation. As a consequence, the Dirac’s [...]

1920 12899

Open Access Review

Revolutionizing Infrastructure Development: Exploring Cutting-Edge Advances in Civil Engineering Materials

Received: 04 July 2023;  Published: 26 September 2024;  doi: 10.21926/rpm.2403023

Abstract

This study addresses the evolving challenges in infrastructure development by exploring recent advancements in civil engineering materials. The problem lies in the limitations of traditional materials such as concrete and steel, which, while foundational, may not fully meet the demands of modern construction in terms of sustainability, durability, and resilience. The objective of this review is to assess the role and impact of both traditional and emerging materials, including supplementary cementitious materials, [...]

2143 12855

Open Access Research Article

Life Cycle Assessment of North American Laminated Strand Lumber (LSL) Production

Received: 18 June 2021;  Published: 15 December 2021;  doi: 10.21926/rpm.2104048

Abstract

Raw materials for buildings and construction account for more than 35% of global primary energy use and nearly 40% of energy-related CO2 emissions. The Intergovernmental Panel on Climate Change (IPCC) emphasized the drastic reduction in GHG emissions and thus, wood products with very low or negative carbon footprint materials can play an important role. In this study, a cradle-to-grave life cycle assessment (LCA) approach was followed to quantify the environmental impacts of laminated strand lumber (LSL). The inven [...]

1470 12664

Open Access Original Research

Deflection of a Concrete T-beam with Prestressed and Non-prestressed Fiber Reinforcement Polymers at Elevated Temperatures

Received: 15 November 2020;  Published: 15 January 2021;  doi: 10.21926/rpm.2101002

Abstract

Prestressed concrete members have gained popularity as an efficient and effective way of designing a structural member with the best engineering and material properties. The method of prestressing a structural concrete member has the capability of controlling increased service loads with less depth over longer spans. However, deflections from over-loading or loading over time give a disadvantage to the common steel reinforced concrete members by the effect of corrosion as the structural concrete develop cracks. To [...]

1821 12641

Open Access Original Research

Obtaining of WC–Co- and WC–TiC–Co-Based Ultradispersive Alloys Modified with B4C–TiB2 Quasieutetic

Received: 21 March 2024;  Published: 26 August 2024;  doi: 10.21926/rpm.2403021

Abstract

Tungsten carbide WC-based materials characterized by high hardness and wear resistance have long been widely used in manufacturing cutting and mining tools. They are alloyed or modified with different ceramic phases to improve operational characteristics further. There are obtained the hard tungsten carbide–cobalt WC–Co and tungsten carbide–titanium carbide–cobalt WC–TiC–Co metal-ceramic alloys ultradispersed powders modified with quasieutectic ceramic alloy B4C–30wt.%TiB2 [...]

1709 12515

Open Access Original Research

Hydration and Microwave Curing Temperature Interactions of Repair Mortars

Received: 24 June 2021;  Published: 09 October 2021;  doi: 10.21926/rpm.2104040

Abstract

Microwave curing of repair patches provides an energy efficient technique for rapid concrete repair. It has serious economic potential due to time and energy saving especially for repairs in cold weather which can cause work stoppages. However, the high temperatures resulting from the combination of microwave exposure and accelerated hydration of cementitious repair materials need to be investigated to prevent potential durability problems in concrete patch repairs. This paper investigates the time and magnitude of [...]

1364 12443

Open Access Original Research

Assessment of Mineral Gain in White Spot Lesions Using CPP-ACP and CPP-ACFP in Different Clinical Protocols: A Proof of Concept Study

Received: 28 September 2021;  Published: 26 November 2021;  doi: 10.21926/rpm.2104046

Abstract

Subsurface remineralization can be promoted by the topical application of nanoparticles of casein phosphopeptide-amorphous calcium phosphate (CPP-ACP). To assess changes in enamel white spot lesions, an in situ proof-of-concept investigation was performed using 5 subjects (all of whom were healthy young adults) with a cross-over study design. Custom orthodontic brackets were attached to the buccal surfaces of the maxillary second premolar and first molar teeth. Each bracket had a recess that held a slab of enamel w [...]

1536 12372

Open Access Review

Effects of Quantum Confinement of Hydrogen in Nanocavities – Experimental INS Results and New Insights

Received: 31 March 2020;  Published: 23 June 2020;  doi: 10.21926/rpm.2002015

Abstract

Current developments of non-relativistic quantum mechanics appear to predict, and reveal, counter-intuitive dynamical effects of hydrogen in nanostructured materials that are of considerable importance for basic research as well as for technological applications. In this review, the experimental focus is on H2O and H molecules in carbon nanotubes and other nanocavities that have been experimentally investigated using the well-established technique of incoherent inelastic neutron scattering (INS). For instance, the [...]

2220 12354

Open Access Original Research

Micromechanics-Based Modeling of SiC/SiC Ceramic Matrix Composites and Structures

Received: 23 January 2023;  Published: 20 June 2023;  doi: 10.21926/rpm.2302025

Abstract

The behavior and response of ceramic matrix composites (CMCs), in particular silicon carbide fiber reinforced silicon carbide matrix (SiC/SiC), is affected by many factors such as variation of fiber volume fraction, residual stresses resulting from processing of the composites at high temperature, random microstructures, and the presence of matrix flaws (e.g., voids, pores, cracks etc.) as well as general material nonlinearity and heterogeneity that occurs randomly in a composite. Residual stresses arising from the [...]

1797 12328

Open Access Review

Impact of Pernicious Chemicals on Geopolymer and Alkali-Activated Composites Incorporated with Different Fiber Types: A Review

Received: 27 March 2024;  Published: 22 July 2024;  doi: 10.21926/rpm.2403017

Abstract

Over the past decade, developing geopolymer mixes to replace ordinary Portland Cement (OPC) composites has yielded positive results, leading to extensive research. The incorporation of fibers in geopolymers, besides impacting the mechanical properties, has also significantly impacted durability, mainly when dealing with the most pernicious forms of deterioration resulting from chloride attack, water penetration, sulfate attack, acid attack, as well as freeze-thaw, which occurred through chemical transgression. This [...]

1219 12241

Open Access Original Research

Green Synthesis of Metal-Organic Biohybrid (Mob) Nanomaterials

Received: 02 August 2022;  Published: 17 October 2022;  doi: 10.21926/rpm.2204020

Abstract

Green synthesis of nanomaterials endeavors to reduce the use of high energy methods with those that may include lower temperatures and pressures, use of natural products, and bottom-up self-assembly. Here we describe the generation of metal-organic biohybrids (MOBs) with nanoscale features synthesized at physiological (37°C) and room temperature (25°C). These MOBs utilized the naturally occurring amino acid dimer cystine as the biological component, and a series of metals, including copper, silver, and cobalt. The [...]

1562 12231

Open Access Review

Research Progress in Enhancing Proton Conductivity of Sulfonated Aromatic Polymers with ZIFs for Fuel Cell Applications

Received: 22 June 2024;  Published: 04 November 2024;  doi: 10.21926/rpm.2404025

Abstract

The escalating global temperatures and their adverse effects underscore the growing imperative for the widespread adoption of clean fuels, notably hydrogen. Proton Exchange Membrane Fuel Cells (PEMFC) emerge as a pivotal green energy technology, facilitating electricity and water generation. The optimization of PEMFC efficiency hinges on the judicious selection and fabrication of polymer membranes. Within innovative materials, Zeolitic Imidazolate Frameworks (ZIFs) represent a novel subclass within the expansive fa [...]

1673 12203

Open Access Review

Machine Learning in Hazardous Building Material Management: Research Status and Applications

Received: 22 January 2021;  Published: 11 May 2021;  doi: 10.21926/rpm.2102017

Abstract

Assessment of the presence of hazardous materials in buildings is essential for improving material recyclability, increasing working safety, and lowering the risk of unforeseen cost and delay in demolition. In light of these aspects, machine learning has been viewed as a promising approach to complement environmental investigations and quantify the risk of finding hazardous materials in buildings. In view of the increasing number of related studies, this article aims to review the research status of hazardous mater [...]

2187 12160

Open Access Research Article

Classical and Quantum Models of Diffusion

Received: 19 February 2021;  Published: 13 April 2021;  doi: 10.21926/rpm.2102011

Abstract

The objective of the paper is twofold: first, to review the classical diffusion models and show the approximations at the origin of the parabolic character of the classical equations; second, to demonstrate a connection between the quantum and classical models of diffusion. As diffusion is inherently related to the motion of constituents, the consistent models are framed within the dynamics of mixtures. The derivation of diffusion equations is then determined based on the related, pertinent approximations.

2199 12066

Open Access Review

Advances in Nanocarriers for Drug Delivery in Dental Therapies

Received: 19 August 2021;  Published: 28 September 2021;  doi: 10.21926/rpm.2103039

Abstract

Dental caries are one of the major causes of oral degeneration diseases. In order to treat dental-related diseases, it is often challenging and expensive. Recent literature has reported many advances in designing delivery systems utilizing polymers and novel biomaterials. Polymers play an important role in designing many nanoformulations like liposomes, polymeric micelles, polymeric nanoparticles, carbon-based nanoparticles, nano-hydroxyapatite, iron oxide, zirconia, silica, and silver nanoparticles were used to tr [...]

1646 12058

Open Access Review

Quantum Diamonds and the Future of Advanced Processors, Review on Benefits and Challenges

Received: 09 April 2025;  Published: 03 August 2025;  doi: 10.21926/rpm.2503012

Abstract

Nowadays, the development of advanced processors plays a key role in the progress of humanity and the discovery of new sciences, and quantum computers play an essential role in this regard. In this regard, the development of new generation processors is necessary for the development of quantum computers. Quantum diamonds, with their astonishing properties, especially the presence of nitrogen-vacancy (NV) centers in their crystalline structure, are among the most advanced emerging technologies in the field of quantu [...]

3387 11870

Open Access Original Research

Polystyrene Topography Sticker Array for Cell-Based Assays

Received: 15 March 2020;  Published: 14 May 2020;  doi: 10.21926/rpm.2002013

Abstract

Cells can respond to different topographical cues in their natural microenvironment. Hence, scientists have employed microfabrication techniques and materials to generate culture substrates containing topographies for cell-based assays. However, one of the limitations of custom topographical platforms is the lack of adoption by the broad research community. These techniques and materials have high costs, require high technical expertise, and can leach components that may introduce artifacts. In this study, we devel [...]

1971 11853

Open Access Original Research

Tribological Behaviour of Sputter Coated ZnO Thin Films

Received: 13 August 2020;  Published: 22 January 2021;  doi: 10.21926/rpm.2101003

Abstract

The tribological properties of ZnO thin film coated on an aluminium work piece by RF magnetron sputtering were studied as a function of deposition power, substrate coating temperature, heat treatment and rotation speed. The variation in the coefficient of friction of ZnO films produced under various levels of coating parameters and conditions were experimentally determined using a pin-on-disk tribometer. The results showed that with change in deposition conditions and heat treatment, there are significant microstru [...]

1948 11708

Open Access Original Research

Effect of Oil Palm Broom Fiber on the Mechanical Properties of Rice Husk Ash–Blended Concrete

Received: 04 June 2025;  Published: 04 September 2025;  doi: 10.21926/rpm.2503013

Abstract

The high carbon footprint of cement production and the cost and environmental impact of steel reinforcement make conventional concrete unsustainable for long-term use. Reducing cement consumption and identifying sustainable, cost-effective alternatives to steel are critical for lowering construction’s ecological and economic burden. Bio-based supplementary cementitious materials (SCMs), such as rice husk ash (RHA), and natural plant fibers show promise, but prior studies have mostly tested them separately or with v [...]

2733 11704

Open Access Case Report

A Case Study on the Impact of Transportation of Mass Timber Products on the Cradle-to-Gate LCA Results for an Institutional Building

Received: 21 April 2022;  Published: 05 August 2022;  doi: 10.21926/rpm.2203014

Abstract

Mass timber products (MTPs) are being adopted in new building constructions and remodels in the last three decades, credited to their renewable and low carbon footprint characteristics. However, there are no mass timber manufacturers currently existing in Atlantic Canada. Extended distances of transporting MTPs to this region from other Canadian provinces may sacrifice the environmental benefits of using MTPs. This study was aimed to understand, via conducting a cradle-to-gate life cycle assessment (LCA), the envir [...]

1463 11646

Open Access Original Research

Effect of Fiber/Matrix Interface Modification on Basalt Fiber Reinforced Geopolymer Composites

Received: 22 December 2020;  Published: 29 March 2021;  doi: 10.21926/rpm.2101008

Abstract

Continuous fiber reinforced geopolymer matrix composites offer the potential for use in structural applications at temperatures up to 700°C, while enabling the manufacture at temperatures below 100°C. Studies have investigated a variety of high temperature structural fiber reinforcements, including carbon, SiC and Al2O3. While there has been active research into various grades of Al2O3 fibers, SiC is most commonly used for high temperature reinforcement of geopolymers in oxidizing environments. Both familie [...]

2046 11632

Open Access Original Research

Low-Velocity Impact Resistance of Glass Laminate Aluminium Reinforced Epoxy (GLARE) Composite

Received: 16 June 2022;  Published: 12 May 2023;  doi: 10.21926/rpm.2302021

Abstract

This study intends to determine the behavior of glass laminate aluminum-reinforced epoxy (GLARE) and glass fiber-reinforced polymer (GFRP) composites under a low-velocity impact test. Experimental tests and numerical simulations are considered for this investigation. All samples are made by the hand lay-up method. Moreover, specimens are produced with a 7075-T6 aluminium sheet with a 0.5 mm thickness, resin 3001, and E-glass fiber. The drop weight test performs the low-velocity impact at 6.7 J and 10 J impact energ [...]

1519 11602

Open Access Original Research

Theoretical Modelling of Liquid Crystal Electro-Optical Material Display Elements to Achieve Optimal Low Power Consumption Ship Stealth

Received: 29 December 2020;  Published: 14 May 2021;  doi: 10.21926/rpm.2102019

Abstract

Advanced optical stealth techniques are of growing importance in the role of manned and unmanned aircraft or ship platforms. We consider here the concept of using passive reflective display elements rather than high power active light projection to achieve a low observable camouflaged ship platform. This paper presents practical consideration towards minimal radiated power user-driven requirements using adaptive liquid crystal electro-optical methods. Optical reflectivity for a multi-layer liquid crystal cell struc [...]

1930 11466

Open Access Original Research

The Effect of Curing Temperature on the Morphology and Electro-Optical Properties of a Flexible UV-Cured Polymer Dispersed Liquid Crystal (PDLC)

Received: 11 October 2020;  Published: 08 December 2020;  doi: 10.21926/rpm.2004023

Abstract

In this work, the experimental data on flexible PDLC films at the industrial scale and the effect of cure temperature (Tc) on the morphology and electro-optical properties of a UV-cured PDLC system via polymer-induced phase separation (PIPS) method were studied. Under constant UV radiation intebsity and thickness, the morphological parameters such as dimension, number density, and volume fraction of the phase-separated liquid crystal droplets as well as the optical transmissions and switching voltages as a function [...]

1902 11458

Open Access Research Article

Wave Propagation and Scattering due to Debonding in CFRP Strengthened Reinforced Concrete Beams

Received: 28 May 2020;  Published: 27 August 2020;  doi: 10.21926/rpm.2003020

Abstract

Carbon fibre reinforced polymer (CFRP) systems as sheets or plates are commonly used to strengthen and retrofit damaged reinforced concrete beams. In general, the bond between the FRP element and concrete defines the effectiveness of the externally bonded FRP materials. In most cases, the interface bonding behaviour is usually tested via static loading conditions. In this paper, the bonding is verified under dynamic conditions. Wave propagation is modelled in delaminated CFRP strengthened reinforced concrete beam. [...]

2004 11404

Open Access Research Article

Effects of Chemical Stabilisation of Eggshells-Lime and Fly-Ash-Cement on the Structural Strength of Subgrade Soil in Rural Roads

Received: 15 May 2022;  Published: 04 August 2022;  doi: 10.21926/rpm.2203013

Abstract

This study examines the chemical compositions of eggshell powder (ESP) and lime as the soil stabilisers and compared with the compositions of cement and fly-ash to understand the optimal distribution of chemical stabilisers maximising the bearing capacity and structural integrity of subgrade soil. The different proportions of eggshell powder (ESP) (2%, 4%, 6% and 8% of total soil mass) were mixed with a fixed proportion of lime (6% of total soil mass) to analyse the optimum proportion of eggshell maximising the soi [...]

1305 11394

Open Access Research Article

Mechanical and Rheological Properties of 3D Printable Cement Composites

Received: 29 July 2020;  Published: 23 October 2020;  doi: 10.21926/rpm.2004022

Abstract

Additive manufacturing is a recent revolution in the construction field since cementitious materials became printable. This extrusion technique has enabled the construction of very complex geometry with a reduction in costs, time and labour interventions. This study aims to evaluate the possibility of reinforcing 3D printable cementitious composites with the use of nano and micro materials, particularly nano silica, micro silica and microfibrillated cellulose (MFC) which are known for their ability to enhance the f [...]

2223 11160

Open Access Original Research

Do Magnetic Monopoles Exist?

Received: 21 October 2023;  Published: 07 February 2024;  doi: 10.21926/rpm.2401005

Abstract

In this paper, we continue our previous work by discussing the consequences of curvature in spacetime caused by the presence of mass and the implications of this. We address the question raised by Dirac regarding the impact of a magnetic monopole on the quantum world. We discuss quantization concerning the solid angles observed, which may have a connection with a magnetic monopole.

1341 11107

Open Access Original Research

Behavior of RC Buildings under Blast Loading: Case Study

Received: 28 April 2023;  Published: 27 July 2023;  doi: 10.21926/rpm.2303029

Abstract

In recent years, regional wars and terror activities have caused blast-loading effects on reinforced concrete buildings, resulting in catastrophic human and material damage. When a building is exposed to a blast load, a very high air pressure affects the building within a very short duration. To decide on the reconstruction or retrofit of a building exposed to blast loading, the behavior of the building under blast loading should be investigated. In this paper a case study of a RC building exposed to blast loading [...]

1420 11078

Open Access Original Research

Reaction Kinetics and Characterization of Slag-Based, High Strength, “Just-Add-Water” Type (One-Part) Alkali-Activated Binders

Received: 03 February 2022;  Published: 08 April 2022;  doi: 10.21926/rpm.2202006

Abstract

The influence of different levels of alkalinity, expressed using M2O-to-binder ratio (n) and activator SiO2-to-M2O ratio (Ms), (M being the Na+ or K+ cation) on the reaction kinetics, compressive strength development and the reaction product formation in slag-based systems activated using alkali powders are discussed. The fundamental idea is to better understand one-part, “just-add-water” type alkali activated binders that are easy-to-use than the systems that rely on liquid activators. The difference in the behavi [...]

1641 11045

Open Access Original Research

Mesoporous Silica Nanoparticles to Tune Oxidative Degradation Rates in Composite Shape Memory Polymers

Received: 12 September 2019;  Published: 31 December 2019;  doi: 10.21926/rpm.1904008

Abstract

Biomedical applications of shape memory polymers (SMPs) are limited by their biostability, degradability, and possible toxicity risks after implantation. Mesoporous silica nanoparticles (MSNs) were used to increase the oxidative biostability (increase time until degradation occurs) using antioxidants and to induce oxidative degradation through incorporation of hydrogen peroxide-containing MSNs with modified surfaces. The presented results confirm increased oxidative stability using antioxidants, and alternatively, [...]

1797 10968

Open Access Original Research

Experimental and Statistical Evaluation of the Interaction Effect of Recycled Aggregate and Water/Cement Ratio on Concrete Compressive Strength

Received: 07 March 2021;  Published: 28 July 2021;  doi: 10.21926/rpm.2103032

Abstract

The production of concrete using recycled aggregates, obtained from the processing of construction and demolition waste, is extensively practiced worldwide. However, the effect of simultaneous adding fine recycled aggregate and the recycled coarse aggregate on the mechanical properties of concrete is still unfamiliar. This work aims to evaluate the influence of the water/cement ratio (WC Ratio), the fine recycled aggregate content (%FRA), the coarse recycled aggregate content (%CRA), as well as the interaction betw [...]

1732 10923

Open Access Technical Note

Innovation in Skin Regeneration: Novel Approaches with β-1,3/1,6-Glucan-Based Treatments

Received: 06 April 2020;  Published: 11 May 2020;  doi: 10.21926/rpm.2002011

Abstract

Skin regeneration is a multidisciplinary topic that involves plastic surgery, aesthetics, and dermatology. In the last few years, several molecules have been used to prevent or delay the skin aging process. Recently, promising investigations on novel β-1,3/1,6-glucan-based treatments, associated with sodium hyaluronate, have demonstrated the induction of a naïve biological stimulus in soft tissues. Serum Revitalizing Face (Lot 00118a0051 of 11/19/2018 approved by the Italian Ministry of Health as a Medical Device-C [...]

1741 10801

Open Access Research Article

Phase Equilibrium in ZrO2-CeO2-Eu2O3 System at a Temperature of 1500 °C

Received: 24 May 2021;  Published: 02 September 2021;  doi: 10.21926/rpm.2103036

Abstract

The phase equilibria and structural transformations in the ternary ZrO2-CeO2-Eu2O3 system at 1500 °C were studied by X-ray diffraction and scanning electron microscopy in the overall concentration range. The system was found to constitute fields of solid solutions based on the tetragonal (T) modification of ZrO2, cubic (C) and monoclinic (B) modifications of Eu2O3, cubic with a fluorite-type structure (F) modifications of CeO2 (ZrO2), and ordered intermediate phase with a pyrochlore-type structure of Eu2Zr2O [...]

1967 10767

Open Access Original Research

Feasibility Study on the Use of Modified Copper Slag as a Sustainable Fine Aggregate in Mortar

Received: 09 March 2021;  Published: 02 June 2021;  doi: 10.21926/rpm.2102022

Abstract

Depending on the availability of aggregate sources pertaining to their geographic locations, the concrete industry utilizes conventional aggregates such as marine sand, dredged gravel, or crushed rocks. This method requires high energy and high processing costs for washing and grinding. The objective of this work is to use Modified Ferro silicate slag (MFS), a by-product obtained from the copper industry, as an alternative to the conventional fine aggregates found in mortar. No additional processing such as washing [...]

1869 10755

Open Access Original Research

Production of Fermentable Sugars from Cassava Stem using Hybrid Pretreatment Technology

Received: 29 April 2021;  Published: 14 September 2021;  doi: 10.21926/rpm.2103037

Abstract

One of the crucial steps in the enzymatic hydrolysis of biomass is pretreatment. We investigated the applicability of a hybrid pretreatment method, This involved acid treatment followed by alkali before the production of fermentable sugars from cassava stem. The substrate was initially treated with acid (1% oxalic acid at 100 °C for 2 h), followed by treatment with a 10% NaOH–urea mixture (by mixing 5 g each of NaOH and urea in 100 mL of water) at 100 °C for 1 h. A cellulose recovery of 98.55% was obtained with the [...]

1402 10749

Open Access Review

Advances in Quantum Properties of Graphene and Derivatives Applied to Functional Nanomaterials and Metamaterials

Received: 30 December 2022;  Published: 13 February 2023;  doi: 10.21926/rpm.2301008

Abstract

In the present work we describe the most important quantum properties of graphene and derivatives recently published. We discuss how these properties were incorporated into varied hybrid materials such as substrates for specific tuning of matter to track varied quantum signals. Their potential applications were analyzed from nanomaterial and nanotechnology. In particular graphene, its derivatives and other carbon-based allotropes were chosen due to their special chemical structure and properties from the nanoscale [...]

1474 10561

Open Access Research Article

Enhanced Long-term Antithrombogenicity Instigated by Covalently-Attached Surface Modifier on Biomedical Polymers

Received: 03 May 2020;  Published: 18 August 2020;  doi: 10.21926/rpm.2003019

Abstract

During a variety of medical procedures such as renal dialysis, bypass surgery, and lung transplantation patient blood is exposed to the surface of a number of polymeric materials such as polycarbonate (PC), poly (vinyl chloride) (PVC) and polysulfone (PS) for a period up to several days. Such exposure may result in undesirable protein-material interactions that can potentially trigger deleterious biological processes including thrombosis, which may be responsible for other complications such as cognitive disability [...]

2190 10500

Open Access Original Research

Detection of Anomalies in Additively Manufactured Metal Parts Using CNN and LSTM Networks

Received: 10 January 2023;  Published: 26 July 2023;  doi: 10.21926/rpm.2303028

Abstract

The process of metal additive manufacturing (AM) involves creating strong, complex components by using fine metal powders. Extensive use of AM methods is expected in near future for the production of small and medium-sized batches of end-use products and tools. The ability to detect loads and defects would enable AM components to be used in critical applications and improve their value. In this study, the Surface Response to Excitation (SuRE) method was used to investigate wave propagation characteristics and load [...]

1433 10415

Open Access Review

An Overview of Treatments for Ultraviolet Quenching Substances (UVQS) and Per- and Polyfluoroalkyl Substances (PFAS) Removal from Landfill Leachate

Received: 15 September 2023;  Published: 24 January 2024;  doi: 10.21926/rpm.2401002

Abstract

Organics found in landfill leachate (humic acids, fulvic acids, and hydrophilic fraction) have a solid ability to absorb ultraviolet (UV) radiation, which negatively affects UV disinfection; leachate ultraviolet quenching substances (UVQS) can, therefore, have a significant impact on the cotreatment of landfill leachate and sewage in wastewater treatment plants. On the other hand, per- and polyfluoroalkyl substances (PFAS), which pose potential risks to the environment and human health, commonly exist in landfill l [...]

1890 10400

Open Access Review

Current Advancements in the Behavior Analysis of EPDM Elastomers in Peripheral Applications of the Cathodic Side of PEMFC Systems

Received: 30 June 2024;  Published: 04 November 2024;  doi: 10.21926/rpm.2404026

Abstract

This review examines the latest developments in the study of how Ethylene Propylene Diene Monomer (EPDM) elastomers behave in peripheral applications of Proton Exchange Membrane Fuel Cells (PEMFCs), specifically on the cathodic side. The review highlights the crucial role of EPDM in maintaining the integrity and efficiency of PEMFCs in challenging conditions characterized by varying temperatures, humidity, and acidic environments. The study examines the impact of various additives and vulcanization procedures on EP [...]

1362 10395

Open Access Original Research

Stress Analysis and Life Prediction of a Ceramic Matrix Composite Vane Using a Micromechanics-Based Approach

Received: 06 September 2023;  Published: 01 December 2023;  doi: 10.21926/rpm.2304035

Abstract

The results of stress analysis of a ceramic matrix composite (CMC) vane using a physics-based model developed for two-dimensional woven CMCs are presented. The model considers the inherent defects and micromechanical damage in woven CMCs along with time-dependent deformation of the constituents. Predictions include damage state under general load conditions and the global deformation response of the vane. Strain-gage data from burst tests are compared to strain predictions obtained using the model. Results from tim [...]

1615 10319

Open Access Original Research

Phase Equilibria of Flexible Polymer and Monomer Liquid Crystal Blends

Received: 05 December 2019;  Published: 03 January 2020;  doi: 10.21926/rpm.2001001

Abstract

In this study, we explored the phase equilibria in blends of a nematic liquid crystal monomer and a nematic liquid crystal flexible polymer within the whole composition of the phase diagram. The crystal-nematic and nematic-isotropic transition temperatures, as well as the transition enthalpies and entropies, indicated the total miscibility in this mesogenic blend system. We also extracted an empirical axial ratio of 4.52 for the polymer from the nematic-isotropic transitions of the blends. Further, from the biphasi [...]

1697 10268

Open Access Original Research

Quantum Chemistry Estimation of Adhesion Strength of Hydroxyapatite with Titanium Substrate

Received: 12 May 2021;  Published: 27 October 2021;  doi: 10.21926/rpm.2104043

Abstract

One of the ways to improve the fusion of an implant with bone tissue is through the use of biocompatible coatings, in particular, hydroxyapatite (HAp). It is important to assess the strength of the HAp adhesion to the implant. The measure of the strength of the bond of the coating with the substrate is the energy of this bond. Using density functional theory and molecular dynamics, the reaction path, reaction products, oscillation frequency, activation energy and bond energy between different combinations of compon [...]

1670 10260

Open Access Original Research

Assessment of the Processing Method for the Development of Hybrid Biopolymer-Based Scaffolds

Received: 01 November 2019;  Published: 26 February 2020;  doi: 10.21926/rpm.2001004

Abstract

The present study deals with the development of scaffolds based on gelatin (G) and/or chitosan (CH) through modifications in the central processing method. This process consists of the fabrication of a hydrogel which is, then submitted to a freeze-drying stage. To compare the effects of the different modifications, the mechanical properties of the various systems were characterized, employing both dynamic compressive strain and frequency sweep tests. In addition, their porosity as well as the structure and fiber di [...]

1727 10173

Open Access Short Review

Bio-Based Substances from the Compost of Bio-Waste for Decontamination of Waste Water

Received: 25 April 2020;  Published: 01 July 2020;  doi: 10.21926/rpm.2003017

Abstract

A literature survey shows that the valorization of urban and/or agricultural biowastes into chemicals has caught the attention of experts and is gradually becoming quite an important issue. This review presents the application of the Bio-Based Substances (BBS) isolated from the compost of bio-wastes from urban gardening and park trimming residues. The non-cost BBS has been well studied in the literature. BBS are biological macromolecules with a complex lignin-derived structure containing several functional groups, [...]

1869 10080

Open Access Review

Super-Resolution of Nano-Materials and Quantum Effects Obtained by Microspheres

Received: 29 July 2019;  Published: 04 September 2019;  doi: 10.21926/rpm.1903003

Abstract

In this article, microsphere super-resolution, which are beyond the Abbe classical limit, are described. The conversion of evanescent waves into propagating waves is analyzed by using the geometry of the microsphere. In microsphere experiments, a nanojet is produced near the focal plane, where its width is smaller than the Abbe limit and remains unchanged in the axial direction for certain wavelengths. The interference between the evanescent waves being converted into propagating waves and the nanojet leads to an i [...]

1893 10038

Open Access Original Research

Antibody-Based Capture and Behaviour of Endothelial Cell Lines on Pre-Surface Modified Medical Grade Steel

Received: 25 January 2020;  Published: 27 March 2020;  doi: 10.21926/rpm.2001008

Abstract

Coronary artery disease is one of the major causes of morbidity and mortality worldwide. Coronary stents, tube-shaped medical implants that are placed in narrowed coronary arteries, have been used successfully in the management of this condition. However, re-narrowing (i.e. restenosis) of the artery can occur which is instigated by an immune response towards the implanted ‘foreign’ material. A new approach to prevent restenosis and reduce the stent-induced immune response has been proposed previously, which involve [...]

1423 10023

Open Access Original Research

Sustainable Concrete with Zero Carbon Footprint

Received: 15 April 2024;  Published: 09 August 2024;  doi: 10.21926/rpm.2403019

Abstract

This paper describes a method to use solely recycled and by-product materials as constituents to form concrete that can be used in buildings structural applications. As concrete is one of the most important materials in human civilization, where it is used widely in construction, cement and aggregate the main components of concrete cause an emission of large amounts of carbon dioxide, which is the main cause of global warming. The production of one tonne of cement, for example, causes the emission of about 800 kg o [...]

1252 10008

Open Access Review

Graphene Quantum Dots from Synthesis to Innovation for Advanced Optics and Bio-Optics Trends

Received: 24 November 2024;  Published: 18 February 2025;  doi: 10.21926/rpm.2501007

Abstract

The generation of non-classical light with improved performances within tiny sizes, intervals of lengths, and diameters is still a challenge. The generation of variable wavelengths associated with different frequencies of energy modes produced from new sources of emitters within confined scales from the Quantum to Nano-and Micro-scales are of high impact. It is noted here that the concept of the generation of non-classical light related to electronics and photonics interactions with different topological matter con [...]

2184 9961

Open Access Original Research

Formulation-Properties of Novel Ibuprofen-Loaded Soy Protein Wound Dressings

Received: 31 July 2019;  Published: 11 October 2019;  doi: 10.21926/rpm.1904004

Abstract

Background:Wound management is an important field in medical care, as annually, millions of wounds require treatment worldwide. Soy protein is highly biocompatible, easily processed, and a relatively cheap natural polymer, which can be used for wound dressing applications. Methods:In this study, solvent cast soy protein films, plasticized by glycerol and cross-linked by glyoxal, were thermally treated and their mechanical properties were evaluated as a function of various processing parameters. Samples were then lo [...]

2119 9910

Open Access Original Research

Enhancement of String Tension Using Thin-Film Metallic Glass Coatings

Received: 16 May 2020;  Published: 15 June 2020;  doi: 10.21926/rpm.2002014

Abstract

Inspired by the application of metallic glass sheet as face material for improving the performance of golf clubs, the present work was aimed to explore the application of thin-film metallic glass (TFMG) coatings for enhancing the performance of strings. In order to achieve this aim, badminton strings were coated with TFMG coatings of different thicknesses. The compositions of these TFMG coatings were analyzed using an electron probe micro-analyzer. The amorphous structure of the film was verified using X-ray diffra [...]

1852 9787

Open Access Original Research

Pilot Study of Tooth Structure Removed in Primary Molar Zirconia Crown Preparations of Typodont Teeth

Received: 10 February 2021;  Published: 28 May 2021;  doi: 10.21926/rpm.2102020

Abstract

Prefabricated zirconia crowns (ZRCs) require a passive fit and more reduction than stainless steel crowns (SSC). To determine the mean and maximum reduction depths in the mesial-buccal and occlusal areas for three ZRC brands and one SSC in posterior primary typodont molars and to compare reduction depths to existing literature to determine the preparation’s proximity to pulpal tissue. Four primary maxillary and mandibular typodont teeth (J and S) were prepared according to the manufacturers’ guidelines for three ZR [...]

1862 9540

Open Access Case Report

Influence of Wetting-Drying Cycles on Wood Behaviour of Coastal Pedestrian Walkways

Received: 30 September 2022;  Published: 11 January 2023;  doi: 10.21926/rpm.2301004

Abstract

In the context of inspection and maintenance actions for beach walkways in the North of Portugal, some samples of wood used in their construction were collected – the Pinus sylvestris wood, widely applied in the country. The sustainability of the beach walkways over natural coastal areas is very dependent on their material durability. One of the main problems of the timber used to build those structures is its behavior under wet-drying cycles. For that reason, this work aimed to simulate the effects of weathering o [...]

1316 9400

Open Access Research Article

Drainage in a Screw Press and Utilization of the Recovered Fibres after Thermo-Hydrolytic Disintegration of Waste Fibreboards

Received: 15 March 2021;  Published: 22 July 2021;  doi: 10.21926/rpm.2103029

Abstract

A thermo-hydrolytic disintegration process qualifies as a promising option for recycling the waste MDF and preserving the fibrous morphology of the recovered lignocellulosic fibre material. This study aims to include a drainage process between the thermo-hydrolytic disintegration and the further utilization of the recovered fibres (RF) obtained using a screw press for removing the disintegration water (DW). In this context, the chemical properties of the RF (pH, nitrogen content, formaldehyde emissions) and the DW [...]

1935 9398

Open Access Review

The Relation between Environmental Risk Analysis and the Use of Nanomaterials in the Built Environment Sector: A Circular Economy Perspective

Received: 02 August 2022;  Published: 11 January 2023;  doi: 10.21926/rpm.2301005

Abstract

Nowadays, the challenge of climate change and “ecological transition” is substantially an “energy challenge” for every city, which is supposed to become as “energetically self-sufficient” as possible. The construction sector is one of the main contributors to the effects of climate change, starting from the production of materials to the use phase of buildings to their demolition. Recent innovations in sustainable/circular design are related to using “new materials." According to this perspective, nanomaterials are [...]

1692 9350

Open Access Original Research

Influence of Recycled Concrete Aggregate Type on Rheological Behaviour of Mixtures Proportioned Using the Equivalent Volume Method

Received: 11 July 2022;  Published: 07 September 2022;  doi: 10.21926/rpm.2203017

Abstract

The ever-growing urgency to combat climate change has led the civil construction industry to develop and adopt sustainable construction materials and methods. The so-called recycled concrete aggregate (RCA) emerges as an alternative to decrease the carbon footprint of new concrete construction, the disposal of waste concrete, and the use of non-renewable natural resources such as cement and aggregates. RCA can be produced from crushing waste concrete; yet challenges remain when using RCA in concrete especially its [...]

1384 9172

Open Access Research Article

Optical, Charge Transport, Thermal, Magnetic, Plasmonic, and Quantum Mechanical Properties of Iridium

Received: 30 July 2022;  Published: 12 October 2022;  doi: 10.21926/rpm.2204019

Abstract

Spectrophotometry has been widely used to retrieve the dielectric function of a bulk iridium sample using an extended version of the Drude–Lorentz model. The parameters of the model are optimized using a spectral-projected-gradient-method-assisted acceptance-probability-controlled simulated annealing approach. Furthermore, optimized values of Drude parameters corresponding to the optical response of electrons and holes (scattering frequency of electrons, the ratio between scattering frequencies of holes and electro [...]

1388 9136

Open Access Research Article

Spontaneous Magnetization in the Finite-Size Two-Leg Ising Ladder in the External Magnetic Field

Received: 30 March 2023;  Published: 24 June 2023;  doi: 10.21926/rpm.2302026

Abstract

This paper considers a finite-sized two-leg ladder of spin-1/2 particles with local inter-chain Ising interaction. We include the effects of an external magnetic field by incorporating a Zeeman-type coupling between the magnetic field and the spins localized on the lattice sites. To analyze the system, we utilize the transfer-matrix formalism to calculate the partition function. We compute the magnetization for different configurations by varying the system's parameters. We observe the presence 3of spontaneous magn [...]

1998 9120

Open Access Original Research

Experimental and Analytical Studies of an Ultra-high Performance Concrete Beam Using Carbon Fiber Reinforced Polymer Bars

Received: 10 September 2022;  Published: 04 May 2023;  doi: 10.21926/rpm.2302019

Abstract

Infrastructure degradation attributable to concrete deterioration and corrosion of reinforcing steel has been a long-standing challenge to the owners and engineers. This problem becomes more evident when concrete structures are subject to aggressively corrosive environments. The use of advanced materials such as ultra-high performance concrete (UHPC) and carbon fiber reinforced polymer (CFRP) bars has a strong potential to overcome this challenge and help build new infrastructure that is durable and sustainable. Ho [...]

1242 9069

Open Access Original Research

The Use of Sulfur Waste to Protect Against Corrosion of Metal Implants

Received: 24 March 2021;  Published: 15 June 2021;  doi: 10.21926/rpm.2102024

Abstract

Metal parts of endoprosthesis have a detrimental effect on the bones that come into contact with them and on the entire body of the patient. Coating them with biocompatible layers (hydroxyapatite and bioglass) has not yet brought about permanent results. In this study, the author showed the possibility of using a binder containing sulfur waste for this purpose. The sulfur binder is used industrially in electrical engineering and construction applications. The chemical properties of elemental sulfur indicate that it [...]

1818 9058

Open Access Original Research

Contactless Detection of Natural Bending Frequencies using Embedded Metallic-Glass Ribbons inside Plastic Beams made of 3-D Printing

Received: 12 December 2020;  Published: 06 April 2021;  doi: 10.21926/rpm.2102010

Abstract

In the current work, to identify the bending mode harmonics, 30 microns thin magnetoelastic ribbons made of metallic glass are embedded inside 6 mm thick PLA plastic cantilever beams made by 3-D printing. This is possible because the ribbons are of magnetoelastic nature and thus change their mechanical state inducing a corresponding change in their magnetic state. The ribbons are placed at four different depths, starting with zero depth at the beam’s external surface all the way inside to the beam’s mid-plane. This [...]

1815 9017

Open Access Research Article

A New Progress in Random Hydrodynamic Lubrication for Movable Non-Rotational Curvilinear Biosurfaces with Phospholipid Bilayers

Received: 08 October 2020;  Published: 02 June 2021;  doi: 10.21926/rpm.2102023

Abstract

This paper aims to highlight the result of a new progression of mathematical estimation methods of stochastic bio-hydrodynamic lubrication parameters for arbitrary, curvilinear, non-rotational, co-operating, living biological surfaces coated with phospholipid bi-layers. Movable, non-rotational, co-operating surfaces occur in various biological friction nods like the collar bone, the blade bone, the jump joint, and the wrist joint. Specifically, the author presents a synthetic and comprehensive estimation of stochas [...]

1829 8960

Open Access Original Research

Effect of Recycled Rubber Particles on the Deicing Salt-Scaling Durability of Concrete

Received: 27 March 2021;  Published: 09 August 2021;  doi: 10.21926/rpm.2103033

Abstract

The present study investigated the effect of reused rubber particles (RRP) on the deicer salt durability of ordinary concrete. Four mixtures were designed, a control concrete (CC) and three other rubber concretes obtained by partial substitution of natural dune sand aggregate with reused rubber particles with 0%, 3%, 6%, and 9% w/w. All studied concretes were subjected to the combined effect of freeze/thaw (56 and 120) cycles with the deicer salt solution of 3% NaCl. The results indicated that RRP improved the deic [...]

1520 8937

Open Access Original Research

Assisted Phytostabilization of Acidic Polymetallic Mine Tailings Using Marble Waste and Native Plant Citrullus colocynthis: Effect on Soil, Plant, and Metal Uptake

Received: 29 December 2020;  Published: 22 July 2021;  doi: 10.21926/rpm.2103030

Abstract

This study aimed to assess the effectiveness of the phytostabilization ability of the native Moroccan plant Citrullus colocynthis on the neutralization of soil acidity and stabilization of metallic trace elements (MTEs) assisted by marble waste. Mine tailings (MT) collected from an abandoned polymetallic site were mixed with powdered marble (PM) using different mixing ratios (%): (MTPM25), (MTPM50), (MTPM75), and agricultural soil (AS) acting as the control. Seeds of C. colocynthis were selected and planted under g [...]

1791 8789

Open Access Original Research

Elastohydrodynamic Squeeze-film Interaction in Synovial Joints with Nanofluid Lubrication

Received: 09 July 2022;  Published: 19 October 2022;  doi: 10.21926/rpm.2204021

Abstract

New lubrication events can be predicted using improved pathological non-Newtonian physiological fluids coupled to phospholipid-based bilayers in variable time-dependent magnetic fields under random non-steady conditions. In this study, we investigated nanofluid lubrication systems for synovial joints. The particles of PSPMA-g-HSNPs were used as nanoparticles. The hydrodynamic interaction between the knee bones separated by a nanofluid film was considered here for various nanofluid concentrations. The simulation ind [...]

1250 8761

Open Access Original Research

Development of Environmentally Ecofriendly Composites Based on Polypropylene/Bahia Beige Waste: Effect of Reinforcement Content on Physical, Mechanical, Chemical, and Microstructural Properties

Received: 22 May 2023;  Published: 18 July 2023;  doi: 10.21926/rpm.2303027

Abstract

This article presents the development and characterization of environmentally friendly composites comprising polypropylene (PP) reinforced with Bahia Beige (BB) marble waste. The composites were prepared using different PP/BB weight ratios and analyzed for their chemical, physical, mechanical, microstructural, and thermal properties. X-ray fluorescence (XRF) analysis revealed the composition of BB, which exhibited a significant concentration of CaO, indicating the presence of calcite and other oxides. X-ray diffrac [...]

1236 8410

Open Access Original Research

Retracted: Performance of Grouted Coupler Embedded in Reinforced Concrete ABC Bridge Pier at Vehicle Impact

Received: 27 September 2022;  Published: 03 January 2023;  doi: 10.21926/rpm.2301001

Abstract

Increased occurrence of dynamic loading on bridge piers caused by seismic, blast and vehicular impact incidences have been increasingly reported. Statistical data shows that while seismic and blast have received significant attention in the literature despite the frequency of occurrence of vehicular impact is remarkably higher. Unfortunately, pier damage caused by high velocity vehicle impact contemplates a little consideration. With the newer construction methods like accelerated bridge construction (ABC) and its [...]

1287 8397

Open Access Original Research

Solubility of Dental Ceramics in Electric Fields

Received: 21 April 2022;  Published: 15 June 2022;  doi: 10.21926/rpm.2202012

Abstract

Combining dental ceramics with other prosthetic metallic restorations might release metal ions, thus affecting the oral tissues of the patients. In this study, we evaluated the electrochemical solubility of various dental ceramics in a galvanic experimental setup in vitro. Smooth and rough feldspathic and zirconium dioxide ceramics (at pH 5.5 and pH 3.0) were exposed to an electric field. Calcium, barium, and zirconium were selected as parameters to determine the solubility of both types of ceramic materials. Among [...]

1302 8342

Open Access Short Review

Versatile Surface Chemistry of Carbon-Based Nanoplatforms by Covalent Bonding, Non-Covalent Linking, Crosslinking, and Self-Assembling

Received: 28 July 2023;  Published: 15 November 2023;  doi: 10.21926/rpm.2304034

Abstract

This mini-review discussed the best-known chemical and synthetic methodologies used in the last years to modify carbon allotropes, with an interest in nanotechnology. In this perspective, chemistry with optoelectronics applications and recent trends within bio-applications focusing mainly on graphene and its derivatives were considered. So, the mini-review intended to focus on methodologies to add functional groups with varied reactivities, polymer chemistry, and nanoscale control. These methodologies provide insig [...]

1265 8325

Open Access Original Research

Indoor Built Environments Attended by Primary School Children and Its Microbiology: A Cross-Project Study

Received: 10 March 2022;  Published: 24 August 2022;  doi: 10.21926/rpm.2203015

Abstract

Exposure to indoor pollutants may exert a significant effect on children health as they spend most of their time in enclosed environments. This research compared the association of biological concentrations with indoor characteristics and building materials in places where children spend significant time indoors. It was compared the results of two autonomous research projects conducted in Porto primary schools and households. Both the projects included a walkthrough inspection and biological measurements in indoor [...]

1294 8283

Open Access Technical Note

Towards Femtoscan-Assisted Analysis of Liquid Crystal Self-Organization on Different Polymer and Glass Surfaces for Lab-on-a-Chip and Lab-on-a-Dish Applications, Including Optofluidic and Flexoelectric Ones

Received: 27 December 2022;  Published: 29 May 2023;  doi: 10.21926/rpm.2302022

Abstract

In this paper, starting with an introductory review of the applications of liquid crystals and polymer-dispersed liquid crystal systems in (bio)sensors and microfluidics, the possibilities of visualizing self-organization products of liquid crystalline media or field-induced instabilities of liquid crystalline systems are considered. In particular illustrated cases, it is proposed to use FemtoScan software-containing metrological complexes to visualize instabilities in liquid crystalline systems and products of sel [...]

1823 8153

Open Access Original Research

Effect of Heat Treatment on Sliding Wear Resistance of Hybrid Aluminum Matrix Composite

Received: 22 December 2022;  Published: 12 April 2023;  doi: 10.21926/rpm.2302015

Abstract

Composite materials with aluminum as matrix material have a wider amplitude of large-scale applications in engineering. Some salient features of aluminum matrix composites are, low density, low thermal coefficient of performance and low weight and high strength. Among the various series of aluminum alloy, Al6061 have been widely used by researchers due to its outstanding properties particularly as they are heat treatable. Aluminum 6061 alloys have been reinforced with various particulate reinforcements such as sili [...]

1198 8084

Open Access Review

Viral/Non-Viral Vectors in DNA/RNA Delivery Technology

Received: 26 August 2024;  Published: 12 December 2024;  doi: 10.21926/rpm.2404027

Abstract

Viral and non-viral vectors for nucleic acids (DNA/RNA) therapeutics are important in development of pharmaceutical industries. Although viral vectors have shown significant impact in transfection of DNA/RNA, but numerus studies have shown that non-viral vectors are also effective for the safe and targeted delivery of DNA/RNA to exact location in the body with high percentage of efficacy, safety, and low-immunogenicity. It is also important to protect the nucleic acids from degradation and large-scale production ca [...]

1912 8082

Open Access Review

Emerging Advances in 3-D & 4-D Printing of Polymeric Nanoarchitectures & Multifacet Applications

Received: 05 September 2024;  Published: 02 February 2025;  doi: 10.21926/rpm.2501005

Abstract

3-Dimension printing (3-DPT) or additive manufacturing (AM) technology has been utilized for a while in the construction of customized 3-D objects utilizing computer software such as computer-aided design (CAD). However, the emergence of an innovative and new four-dimensional printing (4-DPT) has enabled the synergy of AM technology with programmable materials in transforming digital processes virtually into physical entities, thereby providing innovation and advanced functionalities. 4-DPT is a procedure facilitat [...]

2208 8025

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