Special Issue "New Materials and Advanced Procedures of Obtaining and Processing"

A special issue of Applied Sciences (ISSN 2076-3417). This special issue belongs to the section "Materials Science and Engineering".

Deadline for manuscript submissions: closed (31 December 2021) | Viewed by 17845

Special Issue Editor

Dr. Andrei Victor Sandu
E-Mail Website
Guest Editor
Department of Technologies and Equipment for Materials Processing, Faculty of Materials Science and Engineering, “Gheorghe Asachi” Technical University of Iasi, 41 “D. Mangeron” Street, 700050 Iasi, Romania
Interests: material characterization; biomaterials; geopolymers; microscopy
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Special Issue Information

Dear Colleagues,

This Special Issue is focused on highlighting the most recent contributions in the field of materials and procedures from a broad range of applications, from medical to civil engineering.

The main applications are related to materials involved in environmental engineering, medicine, dentistry, and civil engineering, as well as the procedures for the processing and treatment of various materials.

The studied materials can be from nano to macro scale, involving alloys, ceramics, composites, biomaterials, polymers, and more. We welcome the submission of a variety of manuscripts, from theoretical approaches (modeling or simulation) to advanced insights into materials and procedures.

For this Special Issue of Applied Sciences, it is my pleasure to invite you to submit reviews and articles in the abovementioned areas.

Dr. Andrei Victor Sandu
Guest Editor

Manuscript Submission Information

Manuscripts should be submitted online at www.mdpi.com by registering and logging in to this website. Once you are registered, click here to go to the submission form. Manuscripts can be submitted until the deadline. All submissions that pass pre-check are peer-reviewed. Accepted papers will be published continuously in the journal (as soon as accepted) and will be listed together on the special issue website. Research articles, review articles as well as short communications are invited. For planned papers, a title and short abstract (about 100 words) can be sent to the Editorial Office for announcement on this website.

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Published Papers (13 papers)

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Research

Article
Nano-Architectonics of Antibiotic-Loaded Polymer Particles as Vehicles for Active Molecules
Appl. Sci. 2022, 12(4), 1998; https://doi.org/10.3390/app12041998 - 14 Feb 2022
Cited by 2 | Viewed by 764
Abstract
Recently, nanotechnology research studies have been proven that use of various nanoparticles as drug delivery systems to target and to annihilate pathogenic microorganisms may be a good solution for prevention and treatment of severe infection. In the last few years, antimicrobial drug encapsulation [...] Read more.
Recently, nanotechnology research studies have been proven that use of various nanoparticles as drug delivery systems to target and to annihilate pathogenic microorganisms may be a good solution for prevention and treatment of severe infection. In the last few years, antimicrobial drug encapsulation into nano-sized systems has materialized as a promising alternative that increased drug efficacy and minimized adverse effects. Physicochemical properties of erythromycin-loaded polymer nanoparticles were assessed using particle size distribution, HPLC, FTIR, TG/DTA, and SEM characterization techniques. The as-prepared samples exhibited an average particle size of 340 and 270 nm, respectively, with erythromycin content of 99.7% in both samples. From the release profile of erythromycin from PLA/PLGA, a prolonged drug release can be observed from both Ery-PLA and Ery-PLGA nanostructures. Morphology images exhibited spherical, rigid, and ring-shaped nanoparticles. Thermal analytical study in the case of Ery-PLA and Ery-PLGA samples showed that pure drug has an endothermic peak at around 150 °C assigned to a melting point. The antibiotic melting peak disappeared for both antibiotic-loaded PLA and PLGA nanoparticles thermographs, denoting the presence of erythromycin. This indicates that the antibiotic is uniformly dispensed throughout the host polymer matrix at nanometer scale. FTIR spectra of Ery-PLA and Ery-PLGA nano-architectures with almost similar peaks indicated no alteration in chemical structure of drug-loaded polymer nanoparticles. Full article
(This article belongs to the Special Issue New Materials and Advanced Procedures of Obtaining and Processing)
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Article
A Study on the Errors of 2D Circular Trajectories Generated on a 3D Printer
Appl. Sci. 2021, 11(24), 11695; https://doi.org/10.3390/app112411695 - 09 Dec 2021
Viewed by 711
Abstract
This paper presents a study on the movement precision and accuracy of an extruder system related to the print bed on a 3D printer evaluated using the features of 2D circular trajectories generated by simultaneous displacement on x and y-axes. A computer-assisted [...] Read more.
This paper presents a study on the movement precision and accuracy of an extruder system related to the print bed on a 3D printer evaluated using the features of 2D circular trajectories generated by simultaneous displacement on x and y-axes. A computer-assisted experimental setup allows the sampling of displacement evolutions, measured with two non-contact optical sensors. Some processing procedures of the displacement signals are proposed in order to evaluate and to describe the circular trajectories errors (e.g., open and closed curves fitting, the detection of recurrent periodical patterns in x and y-motions, low pass numerical filtering, etc.). The description of these errors is suitable to certify that the 3D printer works correctly (keeping the characteristics declared by the manufacturer) for maintenance purpose sand, especially, for computer-aided correction of accuracy (e.g., by error compensation). Full article
(This article belongs to the Special Issue New Materials and Advanced Procedures of Obtaining and Processing)
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Article
Investigation of the Strength Parameters of Drilling Pumps during the Formation of Contact Stresses in Gears
Appl. Sci. 2021, 11(15), 7076; https://doi.org/10.3390/app11157076 - 30 Jul 2021
Cited by 2 | Viewed by 965
Abstract
The relevance of this research lies in the need to develop scientifically based methods for calculating and designing a transmission shaft with a hardened coating of increased strength and service life of a core drilling pump drive that can allow for a redistributing [...] Read more.
The relevance of this research lies in the need to develop scientifically based methods for calculating and designing a transmission shaft with a hardened coating of increased strength and service life of a core drilling pump drive that can allow for a redistributing of resistance forces along the contact surfaces of the gear. This relevance is confirmed by the need to improve domestic methods for designing drive shafts of increased reliability which can ensure the development of frozen soils during deposits exploration. The purpose of the research is to increase the energy efficiency and service life of the high-loaded drive gear teeth of core drilling pump transmission shafts by justifying the critical loads and stresses in hardened gear coatings acting under intense wear of the contact surface with a broken contact symmetry. The criteria for the effective wear area with an uneven contact cross-section at the maximum bending moments of the transmission shaft of the drilling pump were justified and presented in the work. Additionally, the process of interaction of the transmission shaft gear teeth with the eccentric shaft gear at uneven axial torques was investigated. The effective power (Ng) of the gearing of the drive transmission shaft gear and the eccentric shaft gear, which characterizes the energy consumption of the drill bit depth stroke, was justified. This work also proposes a method of substantiating the technological and power parameters of the transmission shaft by using Legendre polynomials. A nomographic chart was developed for the determination of the dependence of the contact stress base cycles on the change in the load distribution factor and the contact spot deviation factor from the design axis λ. Full article
(This article belongs to the Special Issue New Materials and Advanced Procedures of Obtaining and Processing)
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Article
In Vivo Evaluation of Biocompatibility of Three Biomaterials Used in Endodontics for Prosthetic Purposes in Complex Rehabilitation Treatment
Appl. Sci. 2021, 11(14), 6519; https://doi.org/10.3390/app11146519 - 15 Jul 2021
Viewed by 849
Abstract
The ideal biomaterial used in endodontics in the process of sealing the radicular canals should possess a group of qualities for a predictable outcome: biocompatibility, initiation of ontogenesis and cementogenesis, ease of handling, sufficient manipulation time, and convenient price. For a perfect sealing, [...] Read more.
The ideal biomaterial used in endodontics in the process of sealing the radicular canals should possess a group of qualities for a predictable outcome: biocompatibility, initiation of ontogenesis and cementogenesis, ease of handling, sufficient manipulation time, and convenient price. For a perfect sealing, the root canal treatment can be followed by prosthetic restoration. This study of biocompatibility aims to determine the quantification of the local reaction following the implantation of three biomaterials in the rabbit subcutaneous connective tissue. The used biomaterials with particular reparative properties are: MTA (Mineral Trioxide Aggregate, Dentsply, Tulsa Dental, Johnson City, TN, USA), Sealapex (Kerr, Switzerland), and DiaRoot BioAggregate (Innovative BioCaramix Inc, Vancouver, BC, Canada). The first two biomaterials (MTA, Sealapex) are already being used in endodontic treatments, and the latter was newly introduced during the concrete development of the study. This is an experimental study focused on qualitative and quantitative analysis based on histopathological examination and underlined by the positive result of the study undertaken of the applicability of oral rehabilitation treatments, increasing patients’ quality of life by a significant proportion of 95%, and generating optimal functionality of the stomatognathic system with prosthetic devices as well as accomplishing the objectives of homeostasis. Full article
(This article belongs to the Special Issue New Materials and Advanced Procedures of Obtaining and Processing)
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Article
The Interdisciplinary Approach of Some Middle Bronze Age Pottery from Eastern Romania
Appl. Sci. 2021, 11(11), 4885; https://doi.org/10.3390/app11114885 - 26 May 2021
Cited by 1 | Viewed by 1192
Abstract
Prehistoric pottery is the most abundant material discovered in archaeological sites and represents the main element of knowledge about human communities from the past. This study presents a model of interdisciplinary investigation of pottery through several types of analyses, enabling the scientific study [...] Read more.
Prehistoric pottery is the most abundant material discovered in archaeological sites and represents the main element of knowledge about human communities from the past. This study presents a model of interdisciplinary investigation of pottery through several types of analyses, enabling the scientific study of this category of artifacts. The analyses were performed on 11 ceramic fragments from the Middle Bronze Age settlement of Piatra Neamț–Lutărie, Eastern Romania, considering information about the color, production technique, type, size, functionality and category of the vessel, but also data related to ceramic paste inclusions. The samples were studied by optical microscopy (OM), scanning electron microscopy (SEM) coupled with energy-dispersive X-ray analysis (EDX) and micro-Fourier-transform infrared spectroscopy (µFTIR). The results obtained provide important information regarding pottery manufacturing technologies, such as sources of the raw materials and firing temperatures, and revealed the functionality of various vessel categories within a prehistoric settlement. Full article
(This article belongs to the Special Issue New Materials and Advanced Procedures of Obtaining and Processing)
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Article
Boron-Decorated Pillared Graphene as the Basic Element for Supercapacitors: An Ab Initio Study
Appl. Sci. 2021, 11(8), 3496; https://doi.org/10.3390/app11083496 - 13 Apr 2021
Cited by 3 | Viewed by 995
Abstract
In this work, using the first-principle density functional theory (DFT) method, we study the properties of a new material based on pillared graphene and the icosahedral clusters of boron B12 as a supercapacitor electrode material. The new composite material demonstrates a high [...] Read more.
In this work, using the first-principle density functional theory (DFT) method, we study the properties of a new material based on pillared graphene and the icosahedral clusters of boron B12 as a supercapacitor electrode material. The new composite material demonstrates a high specific quantum capacitance, specific charge density, and a negative value of heat of formation, which indicates its efficiency. It is shown that the density of electronic states increases during the addition of clusters, which predictably leads to an increase in the electrode conductivity. We predict that the use of a composite based on pillared graphene and boron will increase the efficiency of existing supercapacitors. Full article
(This article belongs to the Special Issue New Materials and Advanced Procedures of Obtaining and Processing)
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Article
The Archaeometallurgical Evaluation of Three Bronze Socketed Axes, Discovered in Eastern Romania
Appl. Sci. 2021, 11(4), 1811; https://doi.org/10.3390/app11041811 - 18 Feb 2021
Cited by 2 | Viewed by 1337
Abstract
This paper presents the study of three bronze socketed axes discovered in Neamţ County, Romania. The surface structures and those from the interface of the corrosion layer with the metal core of the basic alloy were analyzed, in order to elucidate the nature [...] Read more.
This paper presents the study of three bronze socketed axes discovered in Neamţ County, Romania. The surface structures and those from the interface of the corrosion layer with the metal core of the basic alloy were analyzed, in order to elucidate the nature of the materials used and the manufacturing processes. The analyzes by optical microscopy (OM) and electron microscopy (SEM), coupled with X-ray spectrometry (EDX), revealed the type of their degradation during the depositional period, as a result of the processes of chemical alteration and physical damage. A series of metallurgical techniques used were also established, as well as the identification of some finishing and decoration processes that led to the establishment of the objects’ functionality. Full article
(This article belongs to the Special Issue New Materials and Advanced Procedures of Obtaining and Processing)
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Article
Parametric Study of the Corrosion of API-5L-X65 QT Steel Using Potentiostat Based Measurements in a Flow Loop
Appl. Sci. 2021, 11(1), 444; https://doi.org/10.3390/app11010444 - 05 Jan 2021
Cited by 2 | Viewed by 1866
Abstract
Low-carbon steel is widely used in industrial pipelines, and corrosion studies are focused mostly on erosion-corrosion, its prediction and control. In this paper, the corrosion rate in pipelines is modeled using a flow loop and measured by linear polarization resistance method (LPR) using [...] Read more.
Low-carbon steel is widely used in industrial pipelines, and corrosion studies are focused mostly on erosion-corrosion, its prediction and control. In this paper, the corrosion rate in pipelines is modeled using a flow loop and measured by linear polarization resistance method (LPR) using a 3-electrode corrosion setup for API-5L-X65 QT steel. Optical microscopy and SEM studies are conducted to examine the surface of the sample and the corrosion products. The effect of NaCl concentration on the corrosion rate is studied at different pH, temperature range, and flow velocities with dissolved oxygen content in the solution maintained at 6 mg/L (6ppm). The corrosion rate is found to be varying from 1 mil per year (0.0254 mmyr−1) to 10 mils per year (0.254 mmyr−1), and the corrosion rate increases with the flow velocity and reaches a maximum at Reynolds Number above 10,000. Further increase in fluid velocity shows corrosion is flow insensitive, and uniform corrosion is predominant in the region. Full article
(This article belongs to the Special Issue New Materials and Advanced Procedures of Obtaining and Processing)
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Article
Corrosion and Tribocorrosion Behaviors for TA3 in Ringer’s Solution after Implantation of Nb Ions
Appl. Sci. 2020, 10(23), 8329; https://doi.org/10.3390/app10238329 - 24 Nov 2020
Cited by 2 | Viewed by 888
Abstract
Ti alloys are prone to corrosion and wear due to the hostile environment in bodily fluids, but the Ti-45Nb alloy is considered to be a promising titanium alloy with excellent biocompatibility and resistance to physiological corrosion. In this study, Nb ions were implanted [...] Read more.
Ti alloys are prone to corrosion and wear due to the hostile environment in bodily fluids, but the Ti-45Nb alloy is considered to be a promising titanium alloy with excellent biocompatibility and resistance to physiological corrosion. In this study, Nb ions were implanted into a TA3 alloy and the effect on the biological corrosion as well as tribocorrosion behavior of TA3 in Ringer’s solution was systematically investigated. The surface microstructure and XRD results revealed that the implanted samples showed a smoother surface due to the sputtering and radiation damages, and the Nb ions mainly existed in the alloy as the solid solution element. The electrochemical polarization tests showed that the implantation of Nb ions can increase the corrosion potential of the samples, showing a better thermodynamic stability. The tribocorrosion tests showed that the implanted samples exhibited a better thermodynamic stability in a corrosive environment accompanied by wear behavior, and the worn surface showed fewer pitting pits, indicating a better corrosion resistance. However, the abrasive wear and oxidation wear degree of the sample increased because of partial softening of the surface and brittle passivation film. Full article
(This article belongs to the Special Issue New Materials and Advanced Procedures of Obtaining and Processing)
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Article
Design of Experiment in the Milling Process of Aluminum Alloys in the Aerospace Industry
Appl. Sci. 2020, 10(19), 6951; https://doi.org/10.3390/app10196951 - 04 Oct 2020
Cited by 15 | Viewed by 1610
Abstract
For many years, surface has quality received a serious attention due to its influence on various mechanical properties. The main contribution made in this scientific paper is the performance of actual experiments, as well as the experimental processing obtained in order to develop [...] Read more.
For many years, surface has quality received a serious attention due to its influence on various mechanical properties. The main contribution made in this scientific paper is the performance of actual experiments, as well as the experimental processing obtained in order to develop a model for predicting the surface roughness based on the optimization of cutting parameters. The novelty of this paper is brought by the method of obtaining the regression equation of the surface roughness, resulted from a standard end-milling process (standard milling tools, standard milling parameters, recommended by the tool manufacturer, 3 axis CNC machine and standard vice), on aluminum alloy 7136 in temper T76511, through two statistical methods of data analysis. This material is used for the production of extruded parts and is poorly understood for the proposed line of research. This study’s aim is to determine the surface roughness equation obtained by the milling of aluminum alloy 7136 in two ways: using Taguchi′s experimental design once and the other, using the central composite design. The Taguchi method and the central composite design are used to develop an efficient mathematical model to predict the optimal level of certain processing parameters. Using ANOVA analysis, a comparative study of calculated and experimental surface roughness values is carried out. The initial characteristics (surface roughness) and the controlled factors (cutting speed, depth of cut and feed) are analyzed with the Minitab program. Finally, an analysis of the advantages and disadvantages of the two methods used is presented. This study has a great industrial application, since the main task of every manufacturer is to achieve a better quality of the final product with minimal processing time. Full article
(This article belongs to the Special Issue New Materials and Advanced Procedures of Obtaining and Processing)
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Article
An Experimental Approach on Beating in Vibration Due to Rotational Unbalance
Appl. Sci. 2020, 10(19), 6899; https://doi.org/10.3390/app10196899 - 01 Oct 2020
Viewed by 1593
Abstract
This paper proposes a study in theoretical and experimental terms focused on the vibration beating phenomenon produced in particular circumstances: the addition of vibrations generated by two rotating unbalanced shafts placed inside a lathe headstock, with a flat friction belt transmission between the [...] Read more.
This paper proposes a study in theoretical and experimental terms focused on the vibration beating phenomenon produced in particular circumstances: the addition of vibrations generated by two rotating unbalanced shafts placed inside a lathe headstock, with a flat friction belt transmission between the shafts. The study was done on a simple computer-assisted experimental setup for absolute vibration velocity signal acquisition, signal processing and simulation. The input signal is generated by a horizontal geophone as the sensor, placed on a headstock. By numerical integration (using an original antiderivative calculus and signal correction method) a vibration velocity signal was converted into a vibration displacement signal. In this way, an absolute velocity vibration sensor was transformed into an absolute displacement vibration sensor. An important accomplishment in the evolution of the resultant vibration frequency (or combination frequency as well) of the beating vibration displacement signal was revealed by numerical simulation, which was fully confirmed by experiments. In opposition to some previously reported research results, it was discovered that the combination frequency is slightly variable (tens of millihertz variation over the full frequency range) and it has a periodic pattern. This pattern has negative or positive peaks (depending on the relationship of amplitudes and frequencies of vibrations involved in the beating) placed systematically in the nodes of the beating phenomena. Some other achievements on issues involved in the beating phenomenon description were also accomplished. A study on a simulated signal proves the high theoretical accuracy of the method used for combination frequency measurement, with less than 3 microhertz full frequency range error. Furthermore, a study on the experimental determination of the dynamic amplification factor of the combination vibration (5.824) due to the resonant behaviour of the headstock and lathe on its foundation was performed, based on computer-aided analysis (curve fitting) of the free damped response. These achievements ensure a better approach on vibration beating phenomenon and dynamic balancing conditions and requirements. Full article
(This article belongs to the Special Issue New Materials and Advanced Procedures of Obtaining and Processing)
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Article
Effects of Dentifrices Containing Nanohydroxyapatite on Dentinal Tubule Occlusion—A Scanning Electron Microscopy and EDX Study
Appl. Sci. 2020, 10(18), 6513; https://doi.org/10.3390/app10186513 - 18 Sep 2020
Cited by 4 | Viewed by 1681
Abstract
This in vitro study evaluated the effects of dentifrices containing nano-hydroxyapatite (n-HAp) on dentinal tubule occlusion and on mineral deposition. Dentin specimens of ten human teeth were submersed for 30 s in 40% citric acid and then randomly divided into four groups (three [...] Read more.
This in vitro study evaluated the effects of dentifrices containing nano-hydroxyapatite (n-HAp) on dentinal tubule occlusion and on mineral deposition. Dentin specimens of ten human teeth were submersed for 30 s in 40% citric acid and then randomly divided into four groups (three study groups and one control group). In the study groups, the dentin samples were exposed to three different n-HAp toothpastes: Karex (Dr. Kurt Wolff GmbH & Co. KG, Bielefeld, Germany), Biorepair Plus Sensitive (Coswell SpA, Bologna, Italy), and Dr. Wolff’s Biorepair (Dr. Kurt Wolff GmbH & Co. KG, Bielefeld, Germany); in the control group no toothpaste was applied. All of the samples were evaluated using scanning electron microscopy (SEM) and energy-dispersive X-ray (EDX) analysis. In the control group all of the samples showed a frank and wide opening of the dentinal tubules, whereas in the study groups different degrees of tubule closure by mineral depositions were observed. Toothpastes containing n-HAp determined a significant occlusion of dentinal tubules and a significant increase of mineral deposition on the dentin surface. All three tested toothpastes showed similar results regarding the degree of dentinal tubule closure. Varying degrees of differences in calcium, phosphate, carbon, and oxygen ion concentrations among the three tested toothpastes were obtained. Full article
(This article belongs to the Special Issue New Materials and Advanced Procedures of Obtaining and Processing)
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Article
Facial Reconstruction: Anthropometric Studies Regarding the Morphology of the Nose for Romanian Adult Population I: Nose Width
Appl. Sci. 2020, 10(18), 6479; https://doi.org/10.3390/app10186479 - 17 Sep 2020
Viewed by 2237
Abstract
Craniofacial reconstruction often represents a final step in medico-legal identification and is dependent on facial tissue thickness measurements and feature shape estimation. This study’s aim is to create a reliable and readily reproductible method of predicting the maximum nose width (MNW) based on [...] Read more.
Craniofacial reconstruction often represents a final step in medico-legal identification and is dependent on facial tissue thickness measurements and feature shape estimation. This study’s aim is to create a reliable and readily reproductible method of predicting the maximum nose width (MNW) based on the maximum nasal aperture width (MAW) for a Romanian adult population. A sample of 55 computer tomography (CT) scans consisting of Romanian adult subjects was selected from the database of a neurosurgery hospital. The craniometrics measured consisted of a first measure of MAW and second one of the MNW using 3D systems Freeform Modelling Plus Software. Correlation analysis indicated a moderate link between the MAW and the MNW. Regression analysis showed that MAW and sex form a statistically significant regression pattern (R2 = 0.340, SEE (Standard Error of Estimate) = 3.801). The preliminary results obtained provide reliable predictions of MNW for facial reconstruction based on MAW measured on the skull. Full article
(This article belongs to the Special Issue New Materials and Advanced Procedures of Obtaining and Processing)
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