Non-metallic Materials Research Articles

On moving average based location charts under modified successive sampling

Ceramics are made up of water, clay, and powders. These are categorized as non-metallic and inorganic materials. It is revealed in the literature that Longquan celadon glaze had irregular cracks in glaze layers due to the relatively high content of $Na_{2}O$. Therefore, it is necessary to monitor the influence of $Na_{2}O$ in the ceramic process. Control charts are a possible tool to monitor the changes in the ceramic process. For single event issues, simple random sampling strategy is utilized; however, modified successive sampling is preferred as the favored sampling strategy at regular intervals of time when the quality of any product is evaluated. Hence, this paper is designed to propose moving average $M{A_{MSS\left( S \right)}}$ and double moving average $DM{A_{MSS\left( S \right)}}$ based control charts to detect small to moderate location shifts using the modified successive sampling technique. We have highlighted the performance evaluations of designed control charts with respect to run-length metrics, and their comparison has been made with the existing $Shewhar{t_{MSS\left( S \right)}}\;$control chart. The results revealed that the $DM{A_{MSS\left( S \right)}}$ performs more efficiently as compared to the $Shewhar{t_{MSS\left( S \right)}}$ and $M{A_{MSS\left( S \right)}}\;$control charts. Further, to demonstrate the application of the designed charts, a dataset of the chemical composition of the ceramic is also utilized.

Multifunctional rare earth oxide/MBG composite microspheres as a carrier for bone tumor treatment

With the development of advanced composites, biomaterials have brought the field of tissue engineering and regeneration into a new era. Among them, composites of inorganic nonmetallic materials and rare earth oxides have unique structures and biochemical properties and have attracted widespread interest. In this work, rare earth oxides (CeO2)/inorganic nonmetallic materials (mesoporous bioactive glass, MBG) composite microspheres (CeO2/MBGs) were synthesized by a sol-gel method, and the in vitro biological effect of CeO2/MBGs was systematically studied. The filling of CeO2/MBGs in irregular bone tumor defects not only promoted osteogenic mineralization in MG63 cells but also had significant antibacterial effects on E. coli and S. aureus. CeO2 enters the MBG network as a network modifier, while doxorubicin (DOX) is adsorbed into the mesoporous structure through electrostatic interactions, which endows CeO2/MBGs with excellent bioactivity and controlled DOX release behavior. Moreover, the results of in vitro experiments showed that the proper addition of rare earth oxides had no toxic effect on normal cells, and the combination of rare earth oxides with antitumor drugs could slow the release of DOX through the use of an intelligent response design system, thus inducing the apoptosis of MG63 cells. This work suggested that combination chemotherapy and the design of a rare earth oxide/MBG composite microspheres may be potential therapeutic approaches for the postoperative repair of bone tumor defects. The construction of this multifunctional rare earth oxide/inorganic biocomposite provides a way to apply the material to bone tissue.

Material Selection of Conductive Fibers for Touchable Gloves and Application of Graphene

In recent years, nanometer conductive materials are the focus of research. Graphene is widely recognized and used in recent years, they have excellent flexibility, mechanical strength and electrical conductivity, with low dimensions and large specific surface area characteristics, in the field of sensors and daily life has great application potential, perhaps some emerging nanomaterials and technologies can provide the possibility of progress for touch screen gloves. Most touchscreen gloves on the market today use metal fibers, but compared with other metals and non-metallic materials, graphene is undoubtedly a suitable and superior conductive fiber choice now and in the future.

Photocatalytic Activity of Ag Nanoparticles Deposited on Thermoexfoliated g-C3N4.

The limited access to fresh water and the increased presence of emergent pollutants (EPs) in wastewater has increased the interest in developing strategies for wastewater remediation, including photocatalysis. Graphitic carbon nitride (g-C3N4) is a 2D non-metal material with outstanding properties, such as a 2.7 eV bandgap and physicochemical stability, making it a promising photocatalyst. This work reports the process of obtaining high-surface-area (SA) g-C3N4 using the thermal-exfoliation process and the posterior effect of Ag-nanoparticle loading over the exfoliated g-C3N4 surface. The photocatalytic activity of samples was evaluated through methylene blue (MB) degradation under visible-light radiation and correlated to its physical properties obtained by XRD, TEM, BET, and UV-Vis analyses. Moreover, 74% MB degradation was achieved by exfoliated g-C3N4 compared to its bulk counterpart (55%) in 180 min. Moreover, better photocatalytic performances (94% MB remotion) were registered at low Ag loading, with 5 wt.% as the optimal value. Such an improvement is attributed to the synergetic effect produced by a higher SA and the role of Ag nanoparticles in preventing charge-recombination processes. Based on the results, this work provides a simple and efficient methodology to obtain Ag/g-C3N4 photocatalysts with enhanced photocatalytic performance that is adequate for water remediation under sunlight conditions.

Mathematical simulation of transverse cut in the fiber of a composite reinforced with unidirectional fibers with linear cohesion cracks

In the reviewed paper, the case of a transverse displacement plane with two pairs of biperiodic (corresponding to the X and Y axes) cohesive cracks of unequal size, weakened by biperiodic circular holes, is considered. The circular holes are filled with reinforcing fibers and the surface is covered with a thin homogeneous non-metallic material of the same thickness. In this case, boundary issues between filler and coating, coating and matrix, and boundary issues along cohesion cracks are determined. For both cases, the solution to the problem is sought in the form of an analytical function with complex variables. According to the boundary conditions of the case, a system of unequal algebraic equations is found along the holes, and singular integral equations are constructed along the cohesion cracks. Currently, the singular integral equations are brought to the system of finite linear algebraic equations with the help of mathematical transformations. Both systems are solved together using the Gaussian method and the crack growth is determined using the stress intensity factor formulas at the crack tips. During the solution of the problem, the stress intensity coefficients at the end are found by the variation of the length of the cracks based on the radius of the circular holes.

Dynamics of bulk and surface oxide evolution in copper foams for electrochemical CO2 reduction

Oxide-derived copper (OD-Cu) materials exhibit extraordinary catalytic activities in the electrochemical carbon dioxide reduction reaction (CO2RR), which likely relates to non-metallic material constituents formed in transitions between the oxidized and the reduced material. In time-resolved operando experiment, we track the structural dynamics of copper oxide reduction and its re-formation separately in the bulk of the catalyst material and at its surface using X-ray absorption spectroscopy and surface-enhanced Raman spectroscopy. Surface-species transformations progress within seconds whereas the subsurface (bulk) processes unfold within minutes. Evidence is presented that electroreduction of OD-Cu foams results in kinetic trapping of subsurface (bulk) oxide species, especially for cycling between strongly oxidizing and reducing potentials. Specific reduction-oxidation protocols may optimize formation of bulk-oxide species and thereby catalytic properties. Together with the Raman-detected surface-adsorbed *OH and C-containing species, the oxide species could collectively facilitate *CO adsorption, resulting an enhanced selectivity towards valuable C2+ products during CO2RR.

Theoretical modeling and experimental investigation of carbon fiber reinforced plastic-based piezoelectric actuator

Piezoelectric actuators based on non-metallic materials have drawn much attention in recent years. Carbon fiber reinforced plastic (CFRP) is one of the ideal materials for the development of lightweight, high power density piezoelectric actuators because of its low density, high stiffness. However, its anisotropic characteristics pose a challenge in actuator development. In this study, we designed a CFRP-based piezoelectric actuator, which utilizes hybrid modes of first-order longitudinal mode and second-order bending mode. The electromechanical coupling dynamic model for CFRP-based piezoelectric actuator was established a, based on the modal superposition method and energy method, and while taking into account the stress-strain relationships in anisotropic materials. The size of the actuator was calculated through the model and a prototype was processed for experimental research. The experimentally obtained results of frequencies and transient- as well as steady-state vibration characteristics demonstrated excellent agreement with the predictions of our mathematical modeling. Actuator performance evaluation results show that under a single-phase excitation voltage of 200 Vp-p, the CFRP-based actuator can reach maximum speed, thrust force, output power, thrust–weight ratio, power density, and efficiency of 617 mm s−1, 65 N, 1.14 W, 980.3 N kg−1, 223.5 W kg−1, and 10.4%, respectively. These results are satisfactory compared with actuators in other reports, especially the power density, which is nearly tripled. These results demonstrate the superior performance of the CFRP-based actuator and illustrate a new approach for developing lightweight and powerful actuators.

Modelling Annihilation Properties of Positronium Confined in Nanoporous Materials: A Review.

Positronium (Ps) is a valuable probe to investigate nanometric or sub-nanometric cavities in non-metallic materials, where Ps can be confined. Accessible experimental measurements concern the lifetime of trapped Ps, which is largely influenced by pick-off processes, depending on the size of the cavity as well as on the density of the electrons belonging to the surface of the host trap. Another relevant physical quantity is the contact density, that is the electron density at the positron position, which is usually found to be well below the vacuum value. Here, we review the principal models that have been formulated to account and explain for these physical properties of confined Ps. Starting with models, treating Ps as a single particle formulated essentially to study pick-off, we go on to describe more refined two-particle models because a two-body model is the simplest approach able to describe any change in the contact density, observed in many materials. Finally, we consider a theory of Ps annihilation in nanometric voids in which the exchange correlations between the electron of Ps and the outer electrons play a fundamental role. This theory is not usually taken into account in the literature, but it has to be considered for a correct theory of pick-off annihilation processes.

Recovery of cathode materials from waste lithium iron phosphate batteries through ultralow temperature treatment and mechanical separation

ABSTRACT Waste lithium iron phosphate (LFP) batteries consist of various of metallic and nonmetallic materials, with lithium being a critical strategic resource in the new energy era. Therefore, recycling LFP batteries has become a primary means of secondary lithium resource recovery. However, the presence of the strong binder polyvnylidene fluoride during the recycling process hinders the efficient recovery and separation of cell materials. This study proposes an innovative approach for recovery, involving ultralow temperature treatment and mechanical separation. In the experimental setup, the ultralow temperature treatment temperature at −140°C for 120 min, followed by 20 s of crushing, resulted in an impressive 96.5% dissociation rate of the cathode material and a purity of 94.2% for lithium iron phosphate. The physical and chemical changes in the cathode materials before and after ultralow temperature treatment were examined using differential scanning calorimetry, scanning electron microscopy, inductively coupled plasma optical emission spectrometer, X-ray fluorescence spectrometer, and X-ray diffraction (XRD). This method has the advantages of low cost, high efficiency, high environmental affinity and no additional products.

DaISy: diffuser-aided sub-THz imaging system.

Sub-terahertz (Sub-THz) waves possess exceptional attributes, capable of penetrating non-metallic and non-polarized materials while ensuring bio-safety. However, their practicality in imaging is marred by the emergence of troublesome speckle artifacts, primarily due to diffraction effects caused by wavelengths comparable to object dimensions. In addressing this limitation, we present the Diffuser-aided sub-THz Imaging System (DaISy), which utilizes a diffuser and a focusing lens to convert coherent waves into incoherent counterparts. The cornerstone of our progress lies in a coherence theory-based theoretical framework, pivotal for designing and validating the THz diffuser, and systematically evaluating speckle phenomena. Our experimental results utilizing DaISy reveal substantial improvements in imaging quality and nearly diffraction-limited spatial resolution. Moreover, we demonstrate a tangible application of DaISy in the scenario of security scanning, highlighting the versatile potential of sub-THz waves in miscellaneous fields.

Trial Manufacture and Performance Research of Hydraulic Oil Tank for Three Kinds of Non-Metallic Materials

With the increasing demand for lightweight construction machinery, it is of great significance to study non-metallic materials that can replace steel plates to make hydraulic oil tanks (HOTs). To explore the feasibility of making HOTs with three materials—cross-linked polyethylene (XLPE), polypropylene (PP), and nylon (PA)—this paper takes 28 L and 115 L volumes commonly used in construction machinery, such as forklifts and loaders, as the design volume and obtains non-metal HOT products of good forming quality by regulating the process parameters. Based on the test methods and evaluation bases of the fuel tank in the national standard, the normal-temperature pressure test, high-temperature pressure test, and low-temperature impact test are designed according to the working conditions of the HOTs. Finally, the non-metallic HOT products are tested. The results show that the rotational molding of XLPE material is the easiest, and products of all sizes can be molded, but the mechanical properties and thermal stability of the products are poor. The low-temperature impact resistance of PP products is poor. PA material can be used to create small HOTs, and the product performance is excellent. This research serves as a valuable reference for the non-metallic and lightweight design of HOTs.

Approaches to Developing Cold-Cure Polyurethane Adhesives for Gluing Metallic and Nonmetallic Materials

Approaches to Developing Cold-Cure Polyurethane Adhesives for Gluing Metallic and Nonmetallic Materials

Investigation of Hydrodynamic Characteristics of Pulse-Wave Action for Various Technological Modes of Electric Discharge Installations for the Destruction of Non-Metallic Materials

Investigation of Hydrodynamic Characteristics of Pulse-Wave Action for Various Technological Modes of Electric Discharge Installations for the Destruction of Non-Metallic Materials

In Situ Metallic Coating of Atom Probe Specimen for Enhanced Yield, Performance, and Increased Field-of-View.

Atom probe tomography requires needle-shaped specimens with a diameter typically below 100 nm, making them both very fragile and reactive, and defects (notches at grain boundaries or precipitates) are known to affect the yield and data quality. The use of a conformal coating directly on the sharpened specimen has been proposed to increase yield and reduce background. However, to date, these coatings have been applied ex situ and mostly are not uniform. Here, we report on the controlled focused-ion beam in situ deposition of a thin metal film on specimens immediately after specimen preparation. Different metallic targets e.g. Cr were attached to a micromanipulator via a conventional lift-out method and sputtered using Ga or Xe ions. We showcase the many advantages of coating specimens from metallic to nonmetallic materials. We have identified an increase in data quality and yield, an improvement of the mass resolution, as well as an increase in the effective field-of-view. This wider field-of-view enables visualization of the entire original specimen, allowing to detect the complete surface oxide layer around the specimen. The ease of implementation of the approach makes it very attractive for generalizing its use across a very wide range of atom probe analyses.

АНАЛИЗ МЕТОДОВ ПРАВКИ КОЛЬЦЕВЫХ АЛМАЗНЫХ СВЕРЛ НА МЕТАЛЛИЧЕСКОЙ СВЯЗКЕ

The study objective is to analyze the existing methods to dress annular diamond drills of metal bonds and to develop new schemes of dressing used for diamond grinding tools.
 The paper is devoted to solving the problem, which consists in comparing different dressing methods, analyzing their disadvantages and advantages.
 Research methods are theoretical studies of various methods of annular diamond drill dressing.
 Novelty of the work: schemes for dressing annular diamond drills of metal bonds with free abrasive are developed.
 Research results: the existing methods and schemes for dressing annular diamond drills of metal bonds are analyzed, their main disadvantages and advantages are found. Dressing schemes for the free abrasive method are developed.
 Conclusions: when drilling hard non-metallic materials with annular diamond drills, the tool loses its functionality, glares and needs forced dressing. During the analysis, existing methods and possible dressing options are considered.

A Comparison Study of Carbon and Energy Footprints Between Traditional Metallic and Non-Metallic Materials in the Oil and Gas Sector

A Comparison Study of Carbon and Energy Footprints Between Traditional Metallic and Non-Metallic Materials in the Oil and Gas Sector

Nonmetallic graphite for tumor magnetic hyperthermia therapy

Magnetic hyperthermia therapy (MHT) has garnered immense interest due to its exceptional spatiotemporal specificity, minimal invasiveness and remarkable tissue penetration depth. Nevertheless, the limited magnetothermal heating capability and the potential toxicity of metal ions in magnetic materials based on metallic elements significantly impede the advancement of MHT. Herein, we introduce the concept of nonmetallic materials, with graphite (Gra) as a proof of concept, as a highly efficient and biocompatible option for MHT of tumors in vivo for the first time. The Gra exhibits outstanding magnetothermal heating efficacy owing to the robust eddy thermal effect driven by its excellent electrical conductivity. Furthermore, being composed of carbon, Gra offers superior biocompatibility as carbon is an essential element for all living organisms. Additionally, the Gra boasts customizable shapes and sizes, low cost, and large-scale production capability, facilitating reproducible and straightforward manufacturing of various Gra implants. In a mouse tumor model, Gra-based MHT successfully eliminates the tumors at an extremely low magnetic field intensity, which is less than one-third of the established biosafety threshold. This study paves the way for the development of high-performance magnetocaloric materials by utilizing nonmetallic materials in place of metallic ones burdened with inherent limitations.

“Four Dimensions, Four Stages and Five Supports, Integration of Theory and Practice”-Reform and Practice of Professional Curriculum for Industrial Upgrading

The transformation and upgrading of the manufacturing industry make the problem of “shortage of resources and weak teaching” in the professional curriculum of the ceramic materials obvious. This paper discusses the background and thinking of the curriculum reform of inorganic non-metallic materials engineering major, summarizes the reform thinking of “four dimensions, four stages and five supports, integration of theory and practice” and the achievements since its implementation, and discusses the significance of the reform.

Topaz quartzolite (greisen) in North Bohemia – potential source of the natural abrasive

Topazolite (greisen) is a rock formed essential by quartz and topaz, with accessory white mica, tourmaline, sulphides (molybdenite and arsenopyrite), wolframite and cassiterite. This rock was found in the Krkonoše and Jizera Mountains in the western Sudetes. In Poland, this metasomatic rock occurs at the contact between leucogranite and mica schist (associated with hydrothermal kaolinization) in a narrow zone between the settlements of Rebiszow and Gierałtówek. On Czech territory, similar topaz quartzolite (greisen rock), consisting of up to 65 % quartz and 32 % topaz, was found near the settlements of Růžek and Vítkov near Chrastava in association with orthogneiss. The high content of topaz in this rock offers the possibility of using it as an abrasive in high-speed abrasive water jet technology for cutting and surface treatment of hard metallic and non-metallic materials. In the crushed form, after being concentrated in a treatment plant, topaz could be a natural abrasive with a wide range of applications. However, the results of technological testing of the physical and mineralogical characteristics of the topaz concentrate indicate its unfavorable properties caused by the high fissility of topaz. This leads to losses of topaz during its technological adjustment to the required grain size or during recycling. It has been shown that abrasive concentrates with topaz content above 90 % are promising, especially for special applications of abrasive water jet technology. Mastering the technology for processing of the source raw material, i.e. topaz quartzolite, into a topaz-rich concentrate, and subsequent applied research on the use of topaz abrasives in industry are crucial.

Exploration of metal-free 2D electrocatalysts toward the oxygen electroreduction.

The advancement of economical and readily available electrocatalysts for the oxygen reduction reaction (ORR) holds paramount importance in the advancement of fuel cells and metal-air batteries. Recently, 2D non-metallic materials have obtained substantial attention as viable alternatives for ORR catalysts due to their manifold advantages, encompassing low cost, ample availability, substantial surface-to-volume ratio, high conductivity, exceptional durability, and competitive activity. The augmented ORR performances observed in metal-free 2D materials typically arise from heteroatom doping, defects, or the formation of heterostructures. Here, the authors delve into the realm of electrocatalysts for the ORR, pivoting around metal-free 2D materials. Initially, the merits of metal-free 2D materials are explored and the reaction mechanism of the ORR is dissected. Subsequently, a comprehensive survey of diverse metal-free 2D materials is presented, tracing their evolutionary journey from fundamental concepts to pragmatic applications in the context of ORR. Substantial importance is given on the exploration of various strategies for enhancing metal-free 2D materials and assessing their impact on inherent material performance, including electronic properties. Finally, the challenges and future prospects that lie ahead for metal-free 2D materials are underscored, as they aspire to serve as efficient ORR electrocatalysts.