Metallic Body Research Articles

Chemical analysis and computed tomography of metallic inclusions in Roman glass to unveil ancient coloring methods

This paper describes the analysis of two near-spherical metallic inclusions partially incorporated within two Roman raw glass slags in order to elucidate the process that induced their formation and to determine whether their presence was related to ancient glass colouring processes. The theory of metallic scraps or powder being used in Roman times for glass-making and colouring purposes is widely accepted by the archaeological scientific community, although the assumption has been mainly based on oral traditions and documented medieval practices of glass processing. The analysis of the two inclusions, carried out by X-ray computed tomography, electrochemical analyses, and scanning electron microscopy, revealed their material composition, corrosion and internal structure. Results indicate that the two metallic bodies originated when, during the melting phase of glass, metal scraps were added to colour the material: the colloidal metal–glass system reached then a supersaturation condition and the latter ultimately induced metal expulsion and agglomeration. According to the authors’ knowledge, these two inclusions represent the first documented and studied finds directly associated with the ancient practise of adding metallic agents to colour glass, and their analysis provides clear insights into the use of metallic waste in the glass colouring process.

Ultrafast X-ray Diffraction Study of a Shock-Compressed Iron Meteorite above 100 GPa

Natural kamacite samples (Fe92.5Ni7.5) from a fragment of the Gibeon meteorite were studied as a proxy material for terrestrial cores to examine phase transition kinetics under shock compression for a range of different pressures up to 140 GPa. In situ time-resolved X-ray diffraction (XRD) data were collected of a body-centered cubic (bcc) kamacite section that transforms to the high-pressure hexagonal close-packed (hcp) phase with sub-nanosecond temporal resolution. The coarse-grained crystal of kamacite rapidly transformed to highly oriented crystallites of the hcp phase at maximum compression. The hcp phase persisted for as long as 9.5 ns following shock release. Comparing the c/a ratio with previous static and dynamic work on Fe and Fe-rich Fe-Ni alloys, it was found that some shots exhibit a larger than ideal c/a ratio, up to nearly 1.65. This work represents the first time-resolved laser shock compression structural study of a natural iron meteorite, relevant for understanding the dynamic material properties of metallic planetary bodies during impact events and Earth’s core elasticity.

Ecotoxicological risk assessment of metal cocktails based on maximum cumulative ratio during multi-generational exposures

Humans and wildlife are frequently exposed to complex mixtures of chemicals, with exposure rarely causing only one dominant effect. Consequently, there is an urgent need to develop strategies to assess exposures to multiple, hazardous chemicals and effects of such combinations. Here, the maximum cumulative ratio was used as part of a tiered approach to evaluate and prioritize risks of co-exposures to metals in 781 samples of surface water from Tai Lake, China. Multiple metals, including copper, lead, cadmium, nickel and zinc dominated the hazardous effects on aquatic organisms. Based on species sensitivity distributions developed from genus mean chronic values, crustaceans were the most susceptible to effects of metals. Results of a multi-generation experiment demonstrated adverse effects of mixtures of metals at environmentally relevant concentrations on growth and reproduction of the cladocerans, Daphnia magna and Moina macrocopa. Specifically, when exposed to metals body length and total number of offspring produced per adult female were less than the controls. Resistance of D. magna populations to mixtures of metals was significantly less, while, under similar conditions, M. macrocopa exhibited greater capacity to recover and the response to adverse effects occurred earlier. Demographic analysis models constructed using a Leslie matrix, used to predict population dynamics of the cladocerans, revealed that various effects of metal cocktails on individual-level endpoints was related to attenuation at the population level. By integrating all the observations, it was recommended that densities of populations of cladocerans in surface waters could be a useful parameter for indicating possible detrimental effects induced by toxic chemicals. Results of this study provide novel insights into risks posed by simultaneous exposure to multiple metals and reveal their potential adverse long-term effects on sensitive aquatic organisms.

Thermomechanical characterization of metal-polyurethane bonded joints: effect of manufacturing parameters and working temperature

ABSTRACT Metal-elastomer bonded joints are typical of different industrial applications, specifically pallet truck wheels, where the solid elastomeric layer is bonded to the metal body. This paper focuses on the effect of manufacturing parameters and working temperature, on the shear strength of a metal-elastomer bonded joint. Through a comprehensive experimental test plan, the paper investigates the effect of thermal conditioning of the adhesive, shot peening of the metal adherend, type of solvent-based adhesive, and working temperature of the joint. The test plan uses a TAST-like specimen with a sandwich configuration (metal-elastomer-metal), loaded in order to originate a nearly pure-shear stress state. The results show which parameters influence most the shear strength of the joint helping the designer in maximizing the load-carrying capacity of the joint.

Integrated remote sensing and geophysical techniques for shallow base metal deposits (Zn, Pb, Cu) below the gossan zone at Kalabar, Western Aravalli Belt, India

Occurrences of small base metal deposits are reported along the western margin of Aravalli Belt in India. Surface manifestation of one such deposit is found to occur as gossan zone within the host rock of amphibolite in Kalabar area of Rajasthan State. Assessment of this occurrence through drilling technology is a time-consuming exercise, more expensive and requires huge manpower. In the present study, an attempt has been made to rediscover the mineral deposit in Kalabar area using remote sensing and High-resolution Electrical Resistivity Tomography (HERT) techniques. Spectral data analysis with Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER) sensor shows the characteristic mineral constituents of the gossan zone. 2D electrical resistivity tomograms helped in identifying a narrow vertical zone with low resistivity but high chargeability value up to a depth of 127.9 m. Geospatial analysis of the resistivity data provides the size of the sub-surface deposits. Several exploratory drillings confirm the existence of such deposit up to a depth of 180 m due to presence of highly conductive metallic ore body (Zn, Pb, Cu). Thus, a unique approach is adopted in mineral exploration technology through integrated analysis of surface to sub-surface information. HERT technique is found to be a cost-effective geophysical survey for identifying the geometry and type of shallow base metal deposits.

Artificial Intelligence: A Survey on Evolution and Future Trends

Today, the world has heard a lot about artificial intelligence (AI) and its influence in accomplishing responsibilities, and it has become famous through films, series TV and social networking sites. Artificial Intelligence (AI) is a combination of algorithms and techniques developed by developers and programmers to build metal bodies that can work for centuries with individuals. Despite the interest of everyone in this topic and its spread significantly, most people do not have adequate knowledge and understanding of this science. This science is considered as one of the essential topics in computer sciences and engineering. In this article, it has been decided to write an overview on the topic of artificial intelligence and understand how its ideas started and spread universally. In addition, there is a review of Expert Systems, Artificial Neural Networks, Fuzzy Logic, and AI applications in the medical field and power systems, especially in investigating lung images of people with COVID-19. The idea presented in this article is that the future will soon come when humans and machines will merge into cyborgs or cybernetic creatures, and they will work together when completing tasks. This idea is described as transhumanism.

Осложнения длительно пребывающего в глазу металлического внутриглазного инородного тела

Осложнения длительно пребывающего в глазу металлического внутриглазного инородного тела

EFFECTIVENESS OF MICROELEMENTS IN THE FORMATION OF MECHANISMS OF PROTECTION OF THE BODY UNDER THE INFLUENCE OF ENVIRONMENTAL STRESS FACTORS

Analysis of literature data and the results of our own research show that even with intensive rearing of animals with the use of balanced feeding and keeping them in accordance with the technology - it is almost impossible to avoid stress. And especially, excessive man-made load on agroecosystems also has a negative impact on animal life.
 Factors that cause a decrease in immune status and the emergence of immune pathology in animals include: industrial technology of animal husbandry, chemicalization in crop and livestock production, man-made pressure, dietary imbalance in nutrients and biologically active substances. This increases the impact on the body of heavy metals, which displace nutrients from body tissues, in particular trace elements and replace them in metabolic processes, which is a potential prerequisite for the development of oxidative stress. The mechanism of development of stress reaction of an organism is closely connected with activity of POL (lipid peroxidation) and depression of antioxidant potential. Under these conditions, the ability of the organism to mobilize protective and adaptive capabilities in response to the action of negative factors becomes especially important. Keeping productive animals in adverse conditions, unbalanced feeding are components of immobilization stress, which reduces their productivity, affects reproductive function, metabolic and functional disorders, reducing nonspecific and specific resistance of the organism (Fedoruk & Kravtsiv, 2003; Velychko, 2008; Velychko, 2011).
 Under conditions of man-caused load on the environment, respectively, and animals – it is promising to develop effective methods for regulating the activity of the enzymatic system of antioxidant protection with the help of biologically active substances, in particular trace elements. The results of research confirm that this has a positive effect on the formation of productive and adaptive properties of animals.
 The system of antioxidant protection is a necessary part of non-specific reactions of the organism, a component of the processes of its adaptation to environmental conditions, a component of normal life, a factor in maintaining homeostasis. Widespread immunodeficiency and elucidation of the main links of their pathogenesis have exacerbated the problem of regulating disorders of the immune system. Therefore, knowledge of the patterns of formation of the immune status of animals, especially in the early postnatal period, is important in the development of methods for the correction of immunodeficiency, antioxidant protection.

Crater shape as a possible record of the impact environment of metallic bodies: Effects of temperature, impact velocity and impactor density

Metallic bodies that were the cores of differentiated bodies are sources of iron meteorites and are considered to have formed early in the terrestrial planet region before migrating to the main asteroid belt. Surface temperatures and mutual collision velocities differ between the terrestrial planet region and the main asteroid belt. To investigate the dependence of crater shape on temperature, velocity and impactor density, we conducted impact experiments on room- and low-temperature iron meteorite and iron alloy targets (carbon steel SS400 and iron‑nickel alloy) with velocities of 0.8–7 km s−1. The projectiles were rock cylinders and metal spheres and cylinders. Oblique impact experiments were also conducted using stainless steel projectiles and SS400 steel targets which produced more prominent radial patterns downrange at room temperature than at low temperature. Crater diameters and depths were measured and compiled using non-dimensional parameter sets based on the π-group crater scaling relations. Two-dimensional numerical simulations were conducted using iSALE-2D code with the Johnson–Cook strength model. Both experimental and numerical results showed that the crater depth and diameter decreased with decreasing temperature, which strengthened the target, and with decreasing impact velocity. The decreasing tendency was more prominent for depth than for diameter, i.e., the depth/diameter ratio was smaller for the low temperature and low velocity conditions. The depth/diameter ratios of craters formed by rock projectiles were shallower than those of craters formed by metallic projectiles. Our results imply that the frequency distribution of the depth/diameter ratio for craters on the surface of metallic bodies may be used as a probe of the past impact environment of metallic bodies.

Laboratory stand for studying the interaction of rubbing bodies in a magnetic field

The paper presents the basic principles for the implementation of experimental studies of the tribological characteristics of friction pairs, taking into account the effect of a magnetic field on them. It has been established that modern experimental studies are carried out on laboratory units using powerful tools to analyze the data obtained, which makes it possible to study the structures of systems by changing the properties of materials under the influence of external factors and wear processes. Taking into account the influence and further research in tribo-conjugated metal bodies (for example, a wheel-rail) of such factors as magnetostriction, external magnetic field (constant, alternating, pulsed), current (direct, alternating, pulsed) passing through the contact, acting both separately, and in various combinations, the design of an experimental laboratory installation was proposed and implemented. The installation allows testing with two types of friction sliding and rolling with sliding. To measure the friction force (friction coefficient), a 6-wire bridge circuit is used, which is described in the article. The paper shows a diagram of a noise-immune strain-gauge circuit of the installation, which allows a significant level of interference during research. Due to the fact that the friction coefficient with a change in temperature can vary over a wide range, the proposed installation implements a method for automatic temperature compensation in the contact zone of tribological samples. The use of thermocouples is proposed as temperature sensors. The signals from the thermocouples of the installation are transmitted to a measuring device consisting of an analog-to-digital converter and a personal computer. The proposed laboratory setup allows for a wide range of tribological testing studies and monitoring of processes in the friction zone exposed to the magnetic field.

Health risk assessment of heavy metal accumulation in the food fish, Channa striata from Krishna river, Andhra Pradesh

The new threats to human health from heavy metals are associated with exposure to some selected metals. The study identifies and assessment of the accumulation and levels of five heavy metals (Cd, Cr, Ni, Pb and Zn) in food fish Channa striata of Krishna river, collected from three stations during four seasons of the year i.e June,2019- May2020. The range of metal concentrations recorded were: Cd 1.12-3.35, Cr 1.41-2.89, Ni 1.51 -3.72,Pb 3.29- 7.69 and Zn 13.8 – 29.1 in case of muscle and in case of liver goes to Cd 2.21 – 4.43, Cr 1.74- 3.68, Ni 1.96-3.71, Pb 3.52- 8.09 and Zn 14.5 – 32.6. The spatial variation in concentrations and comparison among seasons indicated that there are significant differences in the concentrations of metals in the muscle and liver for all seasons. The mean metal concentrations varied temporally; metal masses were relatively constant with fluctuations in metal concentrations related to fluctuations in metal body burdens. The metal contamination had significantly higher in both the tissues of Zn and Pb concentrations. According to the guideline values, the concentrations of metals studied do not pose any threat to the health of fish consumers.

Optimization of Spraying Process in Thermal Power Plant using Robot

To synthesize the surface of the metal bodies, a thermal spray coating is used. There is a great need for this new coating technology in today's progressive world where modification of the substrate material is carried out a great deal. Thermal spray covering, electroplating, powder metallurgy and other metallurgical processes are used very quickly in the field of surface modification. We have presented the summary of all different types of thermal spray coating in this review paper and the advantages of high-speed oxy fuel coating. There is a literature review and an experiment was conducted on behalf of that to demonstrate the effect of coating on mild steel plate. Through Robot, we present a proposed optimization of the spraying process in a thermal power plant. We will explore the thermal spraying and oxidation effect on deposited aluminium and bronze in this research work. We present a detailed assessment of the robot kinematics and optimize the generation of the robot trajectory with a focus on the constant relative scanning speed. The results show that the motion behavior of each axis of robot permits to identify the motion problems in the trajectory. This approach enables the generation of robot trajectories in a limited working envelope to be optimised.

Simulation Study on Electromagnetic Response Characteristics of Unfavorable Geological Body Under Complex Conditions

The second phase of the Chongqing Rail Transit Line project has poor rock and soil stability, slow construction progress, complex and variable geological conditions, and development of groundwater, which seriously threatens the safety of life and property. Therefore, this paper takes this as the engineering background to carry out a simulation research of the electromagnetic response characteristics of the unfavorable geological body under complex geological conditions. The results show that the maximum eddy current is formed in the poor geological body, indicating that the transient electromagnetic method is more sensitive to the low resistance body. The closer the tunnel face, the greater the thickness, and the larger the scale, the stronger the electromagnetic response. The induced electromotive force curve of the B value and the Z axis component of the electromagnetic induction intensity shows that the mutual influence of the two bad geological bodies is small. When there is a low-resistance karst body behind the tunnel face, it will have less impact on the detection of bad geological bodies directly in front of the tunnel face. When the metal body is close to the tunnel face, the detection curve of the induced electromotive force in front of the tunnel face is different from when there is no metal body. When the metal body is more than 30 m away from the tunnel face, the impact on the detection result is limited.

Accumulation of trace metals in freshwater macroinvertebrates across metal contamination gradients.

Historical mining activities cause widespread, long-term trace metal contamination of freshwater ecosystems. However, measuring trace metal bioavailability has proven difficult, because it depends on many factors, not least concentrations in water, sediment and habitat. Simple tools are needed to assess bioavailabilities. The use of biomonitors has been widely advocated to provide a realistic measure. To date there have been few attempts to identify ubiquitous patterns of trace metal accumulation within and between freshwater biomonitors at geographical scales relevant to trace metal contamination. Here we address this through a nationwide collection of freshwater biomonitors (species of Gammarus, Leuctra, Baetis, Rhyacophila, Hydropsyche) from 99 English and Welsh stream sites spanning a gradient of high to low trace metal loading. The study tested for inter-biomonitor variation in trace metal body burden, and for congruence amongst accumulations of trace metals within taxa and between taxa across the gradient. In general, significant differences in trace metal body burden occurred between taxa: Gammarus sp. was the most different compared with insect biomonitors. Bivariate relationships between trace metals within biomonitors reflected trace metal profiles in the environment. Strong correlations between some trace metals suggested accumulation was also influenced by physiological pathways. Bivariate relationships between insect biomonitors for body burdens of As, Cu, Mn and Pb were highly consistent. Our data show that irrespective of taxonomic or ecological differences, there is a commonality of response amongst insect taxa, indicating one or more could provide consistent measures of trace metal bioavailability.

Expression and function analysis of crustacyanin gene family involved in resistance to heavy metal stress and body color formation in Exopalaemon carinicauda.

Crustacyanin has the function of binding astaxanthin which is the best antioxidant, and plays an important role in the body color variation of crustaceans. To investigate the causes of body color variation of the ridgetail white prawn, Exopalaemon carinicauda, the present study obtained four subtypes of crustacyanin gene: C1, C2, A1, and A2. Based on fluorescence quantitative polymerase chain reaction, lipocalin-C1 is mainly expressed in the eyestalk, lipocalin-C2 is in the ventral nerve cord, and lipocalin-A1 and lipocalin-A2 are in subcutaneous adipose tissues. Under the inhibiting effect of Cd2+ stress, the expression of four subtypes first increases and then decreases within 24 h, and reaches the maximum at 6 or 12 h. RNA interference experiments showed a decrease in the expression of lipocalin genes in subcutaneous adipose tissue for each subtype, with the body color changing from transparent to red, and the dark red spots on the epidermis changing to bright red. Moreover, the blue protein in the subcutaneous adipose tissue largely disappeared, based on the light micrographs. In view of these findings, the crustacyanin gene appears to fulfill some function in the resistance to heavy metal stress and body color formation of E. carinicauda.

Normal Load and Counter Body Size Influence the Initiation of Microstructural Discontinuities in Copper during Sliding

Near the interface of two contacting metallic bodies in relative motion, the microstructure changes. This modified microstructure leads to changes in material properties and thereby influences the tribological behavior of the entire contact. Tribological properties such as the friction coefficient and wear rate are controlled by the microstructure, while the elementary mechanisms for microstructural changes are not sufficiently understood. In this paper, the influence of the normal load and the size of the counter body on the initiation of a tribologically induced microstructure in copper after a single sliding pass is revealed. A systematic variation in the normal load and sphere diameter resulted in maximum Hertzian contact pressures between 530 MPa and 1953 MPa. Scanning electron microscopy, focused ion beam, and transmission electron microscopy were used to probe the subsurface deformation. Irrespective of the normal load and the sphere diameter, a sharp line-like feature consisting of dislocations, the so-called dislocation trace line, was identified in the subsurface area at depths between 100 nm and 400 nm. For normal loads below 6.75 N, dislocation features are formed below this line. For higher normal loads, the microstructure evolution directly underneath the surface is mainly confined to the area between the sample surface and the dislocation trace line, which itself is located at increasing depth. Transmission Kikuchi diffraction and transmission electron microscopy demonstrate that the misorientation is predominantly concentrated at the dislocation trace line. The results disclose a material rotation around axes roughly parallel to the transverse direction. This study demonstrates the generality of the trace line phenomena over a wide range of loads and contact pressures and the complexity of subsurface processes under a sliding contact and provides the basis for modeling the early stages in the microstructure evolution.

Enhancement of heat transfer in a fatty acid film at the interface of two metallic bodies by applying electric field

Enhancement of heat transfer in a fatty acid film at the interface of two metallic bodies by applying electric field

A Smart Primary Pad With Integrated TMR Sensors for Wirelessly Charged EVs

In this article, a simple and efficient sensing mechanism, using tunneling magnetoresistance (TMR) sensors and a measurement scheme is presented to enable the primary pad to automatically detect and identify the secondary pad in an electric vehicle (EV). In wirelessly charged EVs, a primary pad that can interoperate with different types of secondary pads is highly beneficial. A bipolar pad (BPP) primary can be configured to transfer power to a circular pad (CP) or a double-D pad (DDP) secondary. In the proposed system, during the sensing phase, the primary pad is excited at a very low current ( $k$ ) is clearly observed. This reduces the primary current considerably. In addition, the magnitude of the primary magnetic field is modulated/changed due to the magnetic field of the secondary. When a DDP secondary is present above the primary, a slight yet repeatable change is seen in the primary magnetic field due to the modulation, while the frequency bifurcation is not seen as the $k$ is very low. The simulation and experimental studies show that these features can be used to reliably detect and identify the type of secondary pad. In the prototype developed, TMR sensors are integrated at the optimal locations on the primary pad to sense the change in the magnetic flux density. In addition, the prototype pad and sensor system developed distinguishes between the metallic body and the secondary pad so that an accidental turning on of the primary pad can be avoided. The results, from the laboratory prototype built and tested in detail, validate the functionality and usefulness of the proposed scheme.

Multiple Integrated Antennas for Wearable Fifth-Generation Communication and Internet of Things Applications

This paper proposes integrating multiple antennas into wearable devices for application in fifth-generation (5G) communications and the Internet of Things (IoT). The frequency bands covered were wireless local area network 2.4-GHz/5-GHz channels (2410–2484 MHz), the global positioning system (1575 MHz), narrowband IoT band 8 (880–960 MHz), Global System for Mobile Communications 850/900, and the 5G frequency range 1 n77/78/79 band (3300–5000 MHz). The antennas were configured as a $2\times2$ multiple-input multiple-output system (MIMO). The antenna resonance contribution integrates the slot mode, monopole mode of the three-dimensional frame, and loop coupling monopole mode. The configuration of the independent matching circuits facilitated the effective control of the desired mode and the coverage of the desired bands. All integrated antennas were placed in a watch device ( $37\times 43\times8$ mm3) with a metal body and a metal strap. An integrated miniaturized antenna was designed. The diversity gain and multiplexing efficiency between the MIMO antennas were 9.97dB and above −2dB, respectively. Favorable diversity performance was confirmed. The channel capacity of the $2\times $ 2 MIMO array was determined to be 8.8 bps/Hz. Moreover, its performance was evaluated through the addition of a hand tissue module. The impact of metal straps on antenna radiation performance was discussed. The specific absorption rate (SAR) was examined, and the best results obtained under an SAR of 1 g and 10 g were 0.25 and 0.58 W/kg, respectively. The findings demonstrate the suitability of the antenna for practical applications in 5G communication systems and the IoT.

High-accuracy quasistatic numerical model for bodies of revolution tailored for RF measurements of dielectric parameters

We have developed rotationally symmetrical coaxial chambers for measurements of dielectric parameters of disk-shaped samples, in the frequency range from 1 MHz to several hundred MHz. The reflection coefficient of the chamber is measured and the dielectric parameters are hence extracted utilizing a high-accuracy quasistatic numerical model of the chamber and the sample. We present this model, which is based on the method of-moments solution of a set of integral equations for composite metallic and dielectric bodies. The equations are tailored to bodies of revolution. The model is efficient and accurate so that the major contribution of the measurement uncertainty comes from the measurement hardware.