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In this study, in situ measurements of electrical resistance in pure Ti during severe plastic deformation (SPD) under high pressures are presented. The process of high‐pressure sliding (HPS) is adopted for the SPD so that straining is feasible under various pressures covering α to ω allotropic phase transformation in pure Ti. Anvil surfaces are coated by a plasma‐sprayed alumina layer to maintain electrical insulation between the sample and the anvils during HPS operation. The electrical resistance increases continuously with straining by the HPS processing but the increase in the electrical resistance is more pronounced as the applied pressure increases, particularly when the ω phase formation occurs. The phase transformation is evidenced by X‐Ray diffraction analysis as well as in situ static heating experiment. The continuous increase in the electrical resistance suggests that there is neither critical strain nor avalanche for the phase transformation to the ω phase. [ABSTRACT FROM AUTHOR]

Combining multiple monitoring methods can improve the accuracy of coal damage and fracture behavior detection. In this study, nine coal samples, each with similar P-wave velocities and masses, were subjected to joint monitoring experiments involving multiple physical parameters. The acoustic emission (AE) and resistance information of coal samples were assessed from the initiation of loading to eventual failure under diverse uniaxial loading rates. The characteristic electrical and acoustic parameters were analyzed in combination with coal damage conditions. The results show that, throughout the loading process, resistivity declined gradually with escalation of coal strain, followed by an abrupt nonlinear increase. Deformation before failure reduced coal resistivity by up to 11.39%. As the coal crack area expanded, the resistivity post-failure reached threefold the initial value. The AE ring count peak value corresponded to crack growth, and the AE energy had a power law distribution feature. The frequency band effect of the AE peak frequency was significant, and shear cracks accounted for more than 80%. Resistance and AE ring count exhibited simultaneous responses to coal failure, and the characteristic parameters of acoustic-electrical behavior demonstrated consistent patterns for cracks induced by various loading rates. The time sequence characteristics of the RSD index, which quantified the degree of resistivity fluctuation, corresponded almost exactly to the development process of coal damage described by AE, and the peak value of this index corresponded to the AE event in the time scale. The overall fluctuation degrees in resistivity of coal samples with varying damage levels showed positive correlation with the AE ring count. An acoustic-electric method for characterizing coal damage is summarized, and corresponding resistivity characteristic parameters are proposed. These parameters have a significant response law to coal damage, which is helpful in supplementing a new index for early warning of geological disasters. [ABSTRACT FROM AUTHOR]

The electrical resistance variation of the Sn–20% Pb alloy melt subjected to ultrasonic vibration was investigated using four-electrode method. The modified energy band theory and cavitation dynamics simulation were employed to explain the experimental results. The ultrasonic vibration in the liquid disrupted the melt structure and enhanced the forced vibration of the atoms, resulting in a reversible liquid–liquid structural transformation and a sharp decrease in electrical resistance. The evolution of the optical microstructure suggested that the ultrasonic-induced refining and homogenizing effects of short-range ordered structures were time-sensitive. The numerical simulation of cavitation dynamics indicated that the structural variation was the substantial root for the electrical resistance change by ultrasonic irradiation, and the high energy required for the reversible structural variation was provided by the collapsing cavities. [ABSTRACT FROM AUTHOR]

The fabrication of ternary Cu–Mn–Al alloys through self-propagating high-temperature synthesis and their thermoelectric properties, such as electrical resistivity and the Seebeck coefficient in a wide range of temperatures, were studied. XRD analysis identified the Heusler compound Cu2MnAl in the synthesized compositions as a main precipitated phase. In addition, different secondary phases (Al2Cu, Cu3Al AlCu, and Mn) appear depending on an excess of aluminum or manganese in the green mixture. The magnetization (M–H) curves constructed for the studied alloys showed their weakly ferromagnetic behavior. [ABSTRACT FROM AUTHOR]

The progression of the electrical resistance of graphite foils during spark plasma sintering process (SPS) was investigated at constant temperature and pressure. The study applied various set-ups of the SPS device, and the electrical data used for the evaluation of electrical resistance (heating power and current) was obtained from the SPS apparatus in real-time. The contact resistance and resistance due to graphite foil/s was evaluated by subtracting the resistance of the single punch set-up from the set-up of two punches in direct contact and the set-ups with various graphite foils. The results showed that during the initial stages of sintering, set-up resistance increases with time and that, overall, set-up resistance increases with number of graphite foils. Both contact resistance and resistance due to graphite foils was found to decrease with sintering time. In contrast to previous conceptions, the electrical resistance of graphite foils changes in response to sintering conditions during the SPS process. [ABSTRACT FROM AUTHOR]

This study explored the fascinating field of high-performance nanoscale metallic multilayer composites, focusing on their magnetic, optical, and radiation tolerance properties, as well as their thermal and electrical properties. In general, nanoscale metallic multilayer composites have a wide range of outstanding properties, which differ greatly from those observed in monolithic films. Their exceptional properties are primarily due to the large number of interfaces and nanoscale layer thicknesses. Through a comprehensive review of existing literature and experimental data, this paper highlights the remarkable performance enhancements achieved by the precise control of layer thicknesses and interfaces in these composites. Furthermore, it will discuss the underlying mechanisms responsible for their exceptional properties and provide insights into future research directions in this rapidly evolving field. Many studies have investigated these materials, focusing on their magnetic, mechanical, optical, or radiation-tolerance properties. This paper summarizes the findings in each area, including a description of the general attributes, the adopted synthesis methods, and the most common characterization techniques used. The paper also covers related experimental data, as well as existing and promising applications. The paper also covers other phenomena of interest, such as thermal stability studies, self-propagating reactions, and the progression from nanomultilayers to amorphous and/or crystalline alloys. Finally, the paper discusses challenges and future perspectives relating to nanomaterials. Overall, this paper is a valuable resource for researchers and engineers interested in harnessing the full potential of nanoscale metallic multilayer composites for advanced technological applications. [ABSTRACT FROM AUTHOR]

The effect of copper (II) sulfide (CuS) addition on the superconductivity of (Bi1.6Pb0.4)Sr2Ca2Cu3O10 (CuS)x (x = 0–1.5 wt%) is reported. All samples were prepared via the co-precipitation technique. The XRD patterns revealed that the formation of Bi-2223 phase was not affected by the CuS addition. The temperature-dependent resistance measurements showed a metallic normal state behavior for all samples, with onset transition temperatures Tc onset between 109 and 118 K and zero transition temperatures Tc zero between 96 and 101 K. The intragranular and intergranular diamagnetic transition, intrinsic and coupling peak temperatures, the onset temperature of grain decoupling and the Josephson phase-locking temperature of (Bi1.6Pb0.4)Sr2Ca2Cu3O10 were not suppressed at lower CuS additions (x ≤ 0.2 wt%) but further CuS additions (x = 0.8–1.5 wt%) severely suppressed these properties. The highest Josephson current (10.82 μA) and Josephson energy coupling (22.22 meV) were exhibited by the non-added sample. The volume fraction of the grains decreased when CuS was added which indicated that the intergranular contribution was enhanced as shown by the AC susceptibility curves for all added samples. The highest transport critical current density, Jct at 40 K was for x = 0.2 wt% sample (4713 mA cm−2). The effect of internal lattice strain on the transition temperatures was also discussed. This work showed that lower addition of CuS could enhance the connectivity between the grains and enhance flux pinning. [ABSTRACT FROM AUTHOR]

The fabrication of welded joints in steel sheets has become a focal point, especially in meeting the demands for interconnections within battery packs for electric vehicles (EVs). This study delves into the impact arising from the initiation arc during the micro-tungsten inert gas (TIG) welding of nickel-plated steel sheets. The investigation involved the manipulation of various current modulations and arc lengths. Notably, optimal results were achieved with a 5 mm arc length paired with a 25 A current modulation. Microstructural analysis, conducted through scanning electron microscopy (SEM), unveiled a higher penetration depth, contributing to a more extensive and shallower fusion zone at the interface between the filler metal and the base material. Tensile testing revealed impressive mechanical properties, with the ultimate tensile strength peaking at 90 N/mm2, a yield strength of 85 N/mm2, and the highest elastic modulus. This underscores the weld's robustness in withstanding applied loads and resisting fracture. Furthermore, the calculation of the lowest K factor at 1.0375 indicated a reduction in resistance across the specimen, resulting in enhanced conductivity. Micro-TIG welding emerges as an efficient method for nickel-plated steel in connecting individual battery cells to form a high-capacity battery pack. These interconnections ensure efficient current flow and maintain the overall integrity and performance of the battery pack. The reliability and quality of these interconnects directly affect the battery's efficiency, safety, and lifespan in EVs application. [ABSTRACT FROM AUTHOR]

We investigated semiconductor composite materials of the AlN–50% SiC–Y3Al5O12 system, obtained by free sintering, which exhibit a high level of microwave absorption of 4.6 dB/mm. The activation energy values of electrical conductivity (Ea) for the obtained composites were calculated within the temperature range of 20–800°C. At temperatures close to room temperature (20–150 °C), Ea ranges from 0.120 to 0.075 eV and increases to 0.270–0.275 eV as the temperature rises to 350–800°C. The determined photon energy values of the electromagnetic wave, in the frequency range from 1 to 100 GHz, are from 4.13 × 10–6 to 4.13 × 10–4 eV. Using quantum electrodynamics at the atomic level, we described the process of microwave radiation absorption in the AlN–SiC semiconductor composites. Low-energy photons of electromagnetic waves incident on the surface of the AlN–SiC composite transfer their energy to the conduction electrons in the near-surface layers of the SiC phase and are absorbed by them. The conduction electrons emit photons at the same frequency of the electromagnetic wave, predominantly into the same SiC grains, within 10–8 s. This interaction results in the absorption of electromagnetic radiation, leading to the dissipation of wave energy and subsequent heating of the entire composite: initially, the SiC phase particles and, subsequently, the AlN grains. [ABSTRACT FROM AUTHOR]

Highlights Continuously long carbon nanotube yarns (CNTYs) were integrated into glass fiber weave/vinyl ester composites to act as electrical sensing elements to self‐monitoring damage. A grid comprising one longitudinal and three transverse CNTYs, running through the 125 mm long flexural specimen, was integrated into the top and bottom layers of glass fiber weaves to allow monitoring of the electrical resistance and locate damage. Four‐point bending specimens were tested under cyclic flexural loading, alternating with low‐velocity impacts to monitor damage initiation and progression. The electrical response of the CNTY grid is able to pinpoint the region where damage initiates, accumulates, and propagates under cycling loading, triggered or not by impact. The damage location identified by the electrical response of CNTYs is supported by in situ in‐plane and through‐thickness strain fields measured by digital image correlation (DIC). The correlation between the electrical technique and the DIC‐measured strain fields indicate that the majority of damage occurs through interlaminar stresses at or near the supports and/or loading introduction elements of the flexural test rig. Integrating CNTYs into structural composites enables online damage monitoring, leading to intelligent condition‐based maintenance for naval ships, aircrafts, and other structures, ultimately extending service life and reducing costs. CNTYs were integrated into composites for damage self‐sensing. Electrical response of CNTYs pinpoints the region of damage. Damage caused by cyclic bending and low velocity impacts were identified. Electrically identified damage is supported by DIC. [ABSTRACT FROM AUTHOR]

The electrical stimulation of pedicle screws is a technique used to ensure its correct placement within the vertebrae pedicle. Several authors have studied these screws' electrical properties with the objective of understanding if they are a potential source of false negatives. As titanium screws are anodized with different thicknesses of a high electrical resistance oxide (TiO2), this study investigated, using analytical, numerical, and experimental methods, how its thickness may affect pedicle screw's resistance and conductivity. Analytical results have demonstrated that the thickness of the TiO2 layer does result in a significant radial resistance increase (44.21 mΩ/nm, for Ø 4.5 mm), and a decrease of conductivity with layers thicker than 150 nm. The numerical approach denotes that the geometry of the screw further results in a decrease in the pedicle screw conductivity, especially after 125 nm. Additionally, the experimental results demonstrate that there is indeed an effective decrease in conductivity with an increase in the TiO2 layer thickness, which is also reflected in the screw's total resistance. While the magnitude of the resistance associated with each TiO2 layer thickness may not be enough to compromise the ability to use anodized pedicle screws with a high-voltage electrical stimulator, pedicle screws should be the subject of more frequent electrical characterisation studies. [ABSTRACT FROM AUTHOR]

We consider a model of current distribution in a tungsten sample and a vapor layer produced when the surface is heated by an electron beam. The model is based on solving electrodynamic equations and a two-phase Stefan problem in cylindrical coordinates. Based on the temperature distribution in the computational domain, the electrical resistance and thermopower are calculated via an integral over the electron energy at each grid node. The electromagnetic field configuration is a possible source of rotation of the substance, which is observed in experiments. The simulation results demonstrate the role of thermionic emission and the way of model development. The model parameters are taken from experiments at the Beam of Electrons for materials Test Applications (BETA) facility created at the Budker Institute of Nuclear Physics of the Siberian Branch of the Russian Academy of Sciences. [ABSTRACT FROM AUTHOR]

In the paper an experimental study of the influence of two types of multiwalled carbon nanotubes (MWCNTs) obtained on Ni/0,16MgO (MWCNTs-1) and Co–Mo/Al2O3–MgO (MWCNTs-2) catalysts with micro-sized metals (12–60 μm) on the change of structural and electro- and thermophysical properties of organosilicon elastomer Silagerm 8030 was carried out. It was found that micro-sized particles of aluminium (Al) and bronze (Br) mixed with MWCNTs improve the electrical and thermal conductivity of the elastomer. At the same time, the addition of micro-sized Al in the form of powder to the elastomer matrix resulted in the formation of elongated formations from particles of different sizes up to 60 μm, while Br was characterized by spherical inclusions from particles with sizes from 12 to 30 μm. The analysis of elemental composition showed that the composite with MWCNTs-1 and Al has in its composition, in addition to Al, nickel (Ni) associated with the catalyst particles which in the process of synthesis intercalated into the structure of MWCNTs-1. The presence of silicon (Si), is related to the chemical composition of the elastomer, which has polar Si–O bonds, and carbon (C) corresponds to MWCNTs. The composite containing MWCNTs-2 (2 wt %) with Br (3 wt %) had the maximum thermal conductivity of 0.215 W/(m °C) and the minimum electrical resistivity of 25.784 kΩ at 3×106 Hz. [ABSTRACT FROM AUTHOR]

Electro-conductive fabrics are key materials for designing and developing wearable smart textiles. The properties of textile materials depend on the production method, the technique which leads to high conductivity, and the structure. The aim of the research work was to determine the factors affecting the electrical conductivity of woven fabrics and elucidate the mechanism of electric current conduction through this complex, aperiodic textile material. The chemical composition of the material surface was identified using scanning electron microscopy energy dispersion X-ray spectroscopy. The van der Pauw method was employed for multidirectional resistance measurements. The coefficient was determined for the assessment of the electrical anisotropy of woven fabrics. X-ray micro-computed tomography was used for 3D woven structure geometry analysis. The anisotropy coefficient enabled the classification of electro-conductive fabrics in terms of isotropic or anisotropic materials. It was found that the increase in weft density results in an increase in sample anisotropy. The rise in thread width can lead to smaller electrical in-plane anisotropy. The threads are unevenly distributed in woven fabric, and their widths are not constant, which is reflected in the anisotropy coefficient values depending on the electrode arrangement. The smaller the fabric area covered by four electrodes, the fewer factors leading to structure aperiodicity. [ABSTRACT FROM AUTHOR]

The process of precipitation of Al3Zr particles in cast Al–(0.25–0.4) wt % Zr alloys manufactured by the induction casting method is studied. The effect of zirconium concentration on the structural parameters, hardness, and specific electrical resistance (SER) of cast alloys is investigated. The dependences of hardness and SER on the time of cast alloys annealing at 500°C are plotted. The parameters of the Johnson–Mehl–Avrami–Kolmogorov equation for alloys with different Zr content are determined. The optimal regimes of cast ingot aging are found. Fine wires with ∅0.3 mm are manufactured by the drawing method; their strength, SER, and hardness are studied in the initial state and after heat treatment. The tests of thermal stability of wires are carried out according to the state standard GOST R MEK 62004–2014. [ABSTRACT FROM AUTHOR]

Copyright of Indonesian Journal of Veterinary Science / Jurnal Kedokteran Hewan is the property of Universitas Syiah Kuala, Faculty of Veterinary Medicine and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

In this paper, the effects of M = Mn and Ru substitutions at the Tl site of Tl1−xMx(BaSr)CaCu2O7 (Tl-1212) on the electrical properties and AC susceptibility were investigated. The X-ray diffraction (XRD) and field emission scanning electron microscopy (FESEM) methods were used to examine the phase and microstructure, respectively. All samples showed diffraction patterns with Tl-1212 as the major phase and an increase in the Tl-1223 phase with increasing Mn and Ru substitutions. The microstructure showed partial melting and randomly oriented grains in all samples. The electrical resistance measurements showed metallic normal state behavior for all samples. The zero-resistance transition temperature Tc−zero was the highest for x = 0.4 where Tc−zero was 107K and 90K for Mn and Ru substitutions, respectively. The superconducting transition, Tcχ′ obtained from AC susceptibility measurements increased with Mn and Ru substitutions up to x = 0.4. Using Bean’s model, the current density at the peak temperature of the imaginary part of the AC susceptibility, Jc(Tp) was determined to be between 16 and 22A⋅cm−2 for Mn, and between 15 and 19A⋅cm−2 for Ru-substituted samples. Mn substitution showed a higher transition temperature compared with Ru. This study showed that optimization of the average Cu valence was achieved with Mn and Ru substitutions for x = 0.4 at the Tl site. The ionic radii of the substituting and substituted elements are important factors in enhancing the transition temperature of Tl(BaSr)CaCu2O7 superconductor. [ABSTRACT FROM AUTHOR]

This work aimed to manufacture bioplastics with mechanical and electrical properties for monitoring the Rhizopus stolonifer growth in tomato fruit packaging. Bioplastics were based on chitosan/polyvinyl alcohol (Ch/PVA), chitosan/polyvinyl pyrrolidone (Ch/PVP), and nanoparticles (NPs) of plant extracts at 10% and 30% of concentrations. Bioplastics were exposed to tomato inoculated with R. stolonifer for 6 d at 25°C. Water vapor permeability (WVP), mechanical properties, FTIR, UV–vis, morphology, electrical resistance of bioplastics, and the NPs size were assessed. In bioplastics added with plant extracts, 1.5 times more WVP than in the control group (18–35 gs−1m−1Pa−1) were quantified. Ch/PVA bioplastic showed 51% more tensile strength, 44% more elongation at break, and 40% more Young's modulus than Ch/PVP, regardless of the plant extract. The electrical resistance in Ch/PVA bioplastics with 30% mushroom extract and 10% radish allowed the differentiation between inoculated (109–1010 Ω) and non‐inoculated tomatoes (1010–1011 Ω). The FTIR assay confirmed the presence of each compound used in the bioplastic, and UV–vis confirmed phenols at 300 nm. The NPs measured less than 50 nm. Only Ch/PVA with 30% mushroom and 10% radish can be useful to monitor fungi in tomatoes based on their electrical behavior. [ABSTRACT FROM AUTHOR]

The results of measurements of the frequency dependence of the active resistance of a circular cross-section of aluminum and copper conductors with a various diameter in a wide frequency range from 20 Hz to 2 MHz are presented. Using the skin effect simulation we show that for all types of wires an increased active resistance observed, compared to the theoretical values in the frequency range above 200 kHz, where the skin layer thickness becomes less than 200 μm. This phenomenon may be associated with the manufacturing process of a metal wire by drawing through a die, when defects are formed in the near-surface layer, leading to its increased resistivity. [ABSTRACT FROM AUTHOR]

In order to improve the sensitivity, responsiveness and stability of flexible pressure sensor based on fabric, a variable honeycomb weave fabric with a dome-shaped micro-surface structure was woven by introducing micro-structures in the woven structure design into cotton fabric. Variable honeycomb fabric, carbon black(CB)and polyvinyl alcohol(PVA)were used as raw materials, different sensor fabrics were prepared by immersion method. The relationship between the mass fraction of carbon black and the sensor resistance was tested, the structural morphology and mechanical sensing performance of the prepared sensor were characterized to explore its application in human motion monitoring. The results showed that the prepared sensor had high sensitivity and small hysteresis when the mass fraction of carbon black was 5% and the sensor resistance was decreased to 20 kΩ/cm. Under different pressures and compression rates, the sensor could maintain better stability, repeatability and durability. It is considered that the prepared sensor can be applied to human motion monitoring, including finger pressing, knuckle, wrist and elbow bending movements. [ABSTRACT FROM AUTHOR]

Self-healing techniques are presented in three different ways: The first application is the use of bacteria to calcite in concrete cracks. In this way, relatively large cracks can be filled in reinforced concrete. This method does not improve the strength of the structure, but by filling the crack, the reinforcement path is blocked. This stops the entry of liquids and ions that start to corrode the reinforcement and thus increase the compressive strength but decrease the electrical resistivity of the structure. With this method, cracks can be filled and leakage can be prevented. In designs that use a self-healing additive such as Mix designation 7, the time interval obtained from the accelerated corrosion test between the cracked and intact specimens is reduced. Compressive strength in cracked and intact specimens in these designs is higher than in other designs. The use of more superplasticizers and more Silica fume are effective in these amounts. Its low electrical resistance can lead to increased corrosion intensity thus more superplasticizers in Plan 7 is not preferable to Plan 4. Low electrical resistance can lead to increased corrosion intensity thus Plan 4 is preferable to Plan 7. [ABSTRACT FROM AUTHOR]

This study examines the influence of multiwalled carbon nanotubes (MWCNTs) on cementitious composites, specifically focusing on the fabrication of multifunctional cementitious composites known as ultrahigh-performance cementitious (UHPC) composites. Key properties such as compressive strength, thermal performance, and electrical resistance were examined with varying MWCNT contents, curing methods, curing duration, and supply voltage. The effects of the incorporation of MWCNTs on the hydration reactions of the cementitious composites were analyzed using field-emission scanning electron microscopy, thermogravimetric analysis, and X-ray diffraction. The study revealed that MWCNT UHPC composites can achieve a maximum ultrahigh strength of 120.8 MPa. Additionally, the incorporation of MWCNTs enabled the composites to reach a maximum surface temperature of 90.6 °C during heating. Furthermore, the power consumption of MWCNT UHPC composites was found to be predictable based on the curing type and the duration of curing. Notably, the hydration reactions in MWCNT UHPC composites remained unaffected by the MWCNT content. The findings emphasize the potential of multifunctional MWCNT UHPC composites by offering exceptional strength, heating capabilities, and electrical performance in construction materials.

Microwave-assisted chemical precipitation was used to prepare CuxCd1-xS (x = 0.8, 0.6, 0.4, and 0.2) nanoparticles mixture. The crystal structure, size, and surface morphology of the as-synthesized nanoparticles were studied using X-ray diffraction and SEM. Presence of copper, cadmium, and sulphur in proper ratios in the samples was confirmed by energy-dispersed X-ray analysis. DC electrical resistance measurements of all the samples in the temperature range of 300…500 K showed phase transition above a certain temperature. [ABSTRACT FROM AUTHOR]

Summary: Thawing is necessary to restore the freshness of fish before cooking because fish is often frozen to retain its freshness. Frequently, fish is partially thawed (or 'tempered') as it is easier to handle in this form than fully thawed fish. However, the conventional tempering techniques – immersion in water and still air tempering – take a long time and alter the fish's characteristics. Hence, the aim of this study was to use the heat generated inside the frozen fish, or ohmic heating, to alter the tempering process. Compared with conventional tempering operations, in this study, three voltage levels (20, 30 and 40 V/cm) were used for ohmic tempering. The fish quality and yield findings revealed that 30‐V/cm ohmic heating was more appropriate, even though ohmic heating at 40 V/cm provided the shortest tempering time. The main operating expense for ohmic tempering was the power cost of USD 58.5/100 kg, whereas the major operating expense for water immersion was the cost of water supply and wastewater treatment, which was around USD 108/100 kg. By using ohmic heating instead of still air and water immersion to temper the frozen fish, not only was less time required while retaining the freshness of the fish but the cost of tempering was also reduced. [ABSTRACT FROM AUTHOR]

• Corrosion sensors for VOC based on flexible substrate are proposed for the first time. • Results show sensitivity <1 ppm and linear response behavior. • For the first time, different materials are combined on the same substrate into a multisensor. • The multisensor is able to discriminate among different classes of VOC. Aim of this work is the development of a new kind of corrosion sensors, based on low-cost flexible substrates, specifically designed to detect Volatile Organic Compounds (VOCs) producing significant degradation of artifacts in museum display cases. Sensors have been fabricated and tested in relevant environment with three of the most relevant VOCs (acetic acid, formic acid and formaldehyde) to the artifacts preservation. Sensitivity has been measured to be lower than 1 ppm, which is several times better than what reported in the literature on corrosion sensors for the same VOCs. In addition, different sensors, arranged with different active materials, have been implemented for the first time into a so-called multi-sensor architecture, aimed at demonstrating VOC specificity: in particular, we report here on a preliminary test in which the multi-sensor has been able to be selective between acetic acid and formaldehyde. [Display omitted] [ABSTRACT FROM AUTHOR]

Due to their electroconductive properties, flexible open-cell polyurethane foam/silver nanowire (PUF/AgNW) structures can provide an alternative for the construction of cheap pressure transducers with limited lifetimes or used as filter media for air conditioning units, presenting bactericidal and antifungal properties. In this paper, highly electroconductive metal-polymer hybrid foams (MPHFs) based on AgNWs were manufactured and characterized. The electrical resistance of MPHFs with various degrees of AgNW coating was measured during repeated compression. For low degrees of AgNW coating, the decrease in electrical resistance during compression occurs in steps and is not reproducible with repeated compression cycles due to the reduced number of electroconductive zones involved in obtaining electrical conductivity. For high AgNW coating degrees, the decrease in resistance is quasi-linear and reproducible after the first compression cycle. However, after compression, cracks appear in the foam cell structure, which increases the electrical resistance and decreases the mechanical strength. It can be considered that PUFs coated with AgNWs have a compression memory effect and can be used as cheap solutions in industrial processes in which high precision is not required, such as exceeding a maximum admissible load or as ohmic seals for product security. [ABSTRACT FROM AUTHOR]

Copyright of Industria Textila is the property of Institutul National de Cercetare-Dezvoltare pentru Textile si Pielarie and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The recent increased interest in structural health monitoring (SHM) related to material performance has necessitated the application of advanced data analysis techniques for interpreting the realtime data in decision-making. Currently, an accurate and efficient approach for the timely analyses of large volumes of uncertain sensor data is not well-established. This paper proposes an automated clustering-based piecewise linear regression (ACPLR)-SHM methodology for handling, smoothing, and processing large data sets. It comprises two main stages, where the gaussian weighted moving average (GWMA) filter is used to smooth noisy data obtained from electrical resistance sensors, and piecewise linear regression (PLR) predicts material properties for assessing the performance of concrete in service. The obtained values of stabilized resistance and derived values of diffusion coefficients using this methodology have clearly demonstrated the benefit of applying ACPLR to the sensor data, thereby classifying the performance of different types of concrete in service environments. [ABSTRACT FROM AUTHOR]

Sn–0.7Cu eutectic alloy is a low-cost alloy with moderate melting point and wetting that appears to be adequate for some applications. Lead-free Sn–0.7Cu joint solders on copper substrate were investigated in this study. To enhance the performance of the alloy, many previous studies verified the importance of adding bismuth to the eutectic alloy. (84.3Sn–0.7Cu–15Bi) ternary alloy is regarded as a potential substitute for hazardous Sn–Pb solders, possessing a melting point of 206 °C. The effects of incorporating selenium, zinc, or indium on the electrical characteristics, crystal structure and microstructure of the tin copper-bismuth alloy were examined. Phase identification of the base solder and various newly developed alloys was performed by X-ray diffraction tests and an LCR meter was used to measure the electrical resistance of the prepared samples. The unit cell volume, and lattice parameters of the tetragonal Sn base were altered, along with the electrical characteristics of the base solder alloy. According to the test results, the best addition was by indium since it reduced the grain size of the base solder alloy. Smaller grain size improves the mechanical properties of the solder. Furthermore, indium addition increased the electrical conductivity of the base solder alloy compared to other alloying additions. [ABSTRACT FROM AUTHOR]

Fiber-reinforced emulsified asphalt (FEA) is widely used in asphalt pavement structures as a stress-absorption layer. This study aimed at developing a multifunctional fiber-reinforced emulsified asphalt (MFEA) by empowering the FEA with the self-sensing ability. To achieve this purpose, carbon nanotubes (CNTs) were grafted onto the basalt fibers in the FEA. An optical microscope and scanning electron microscope (SEM) were respectively used to investigate the distribution of CNTs onto the fibers and the microstructure of CNT/fiber composite (CFC). The fabrication process of CFC was optimized based on the distribution homogeneity of the CNTs. The self-sensing ability of the MFEA was then evaluated in the laboratory using an electrochemical workstation. Based on the experimental and analytical results, 1.5 mg/mL was recommended as the optimal dosage of the suspension of CNTs for grafting CNTs onto the fiber. The electrical resistance of the developed MFEA was found to be isotropic and sensitive to the demulsification state, EA/CFC mass ratio, temperature, loading speed, and deformation magnitude, which confirms the potential of using developed MFEA as a self-sensing layer to monitor its response to environmental and traffic variation. Besides, the direct tension and pull-out tests indicate the positive influence of grafting CNTs onto basalt fibers on the mechanical performance of FEA. [ABSTRACT FROM AUTHOR]

Uncertainty about the geometry of jet grouting columns is a serious challenge to the efficiency of jet grouting technology. If this challenge can be met, jet grouting can become an efficient method of soil improvement. One proposed approach is measurement based on changes in the electrical resistivity between the column and surrounding soil. This approach is non-destructive, easy to use, fast and accurate. This paper reviews jet-grouting methods using the experimental research approach and reports on the design and construction of a probe equipped with ring electrodes that is suitable for measurement of the column diameter. The approach is based on the geoelectric method and Wenner theory. The probe was field tested on jet-grouting columns in a project in Bandar-e Gaz. The probe results were validated by visually observing the dimensions of the excavated column. The results showed that the probe performed well. The device measured a 90-cm column as being from 81 to 88 cm with an error of about 10%. The method of measuring the difference in electrical resistance was shown to be an accurate approach to solving the problem of uncertainty in the geometry of jet-grouting columns. [ABSTRACT FROM AUTHOR]

Electrical resistance measurement is central to materials characterization, circuit analysis and resistance-based sensing. Resistance measurement involving the two-probe method (involving two electrical connections) is known to overassess the resistance, due to the electrode-specimen contact resistance. Resistance measurement involving the four-probe method (involving four electrical connections) is advantageous in that it essentially excludes the contact resistance at the connection-specimen interface. Nevertheless, the two-probe method is widely used, because of the simplicity of having only two connections. In the two-probe method, the current passes through the specimen and connections. The connection-related stray inductance is found in this work to cause large additional overassessment of the two-probe resistance when the electrical connection configuration entails current direction changes. The connections pertain to electrical leads and clips. The inductance increase due to a current direction change is in line with Faraday's law. Mere constriction or spreading of the current due to the connections also increases the inductance, but it does not influence the two-probe resistance. The inductance and two-probe resistance increase with the lead length because of the connection-related inductance, not because of the negligible increase in the lead resistance. An inductance increase of ≤ 80% causes a two-probe resistance increase of ≤ 278%. The specimen in this work is aluminum. It does not need to be magnetic. The connections in this work are also not magnetic. This inductance-related source of two-probe resistance overassessment is reported here for the first time. [ABSTRACT FROM AUTHOR]

The dependence of the electrical resistance of a volumetric homogeneous conductor on the area of electrical contacts has been studied by computer modeling methods. To describe this dependence, simple analytical models are proposed, which are suitable for engineering calculations. The problem of resistance of a multilayer structure with a small contact is considered and solved. [ABSTRACT FROM AUTHOR]

Short single-stranded DNA molecules of two types, consisting of dC nucleotides only or dA nucleotides only, were immobilized onto the surface of mica and silver substrates and studied by scanning probe microscopy methods. Geometric dimensions of the studied objects were determined. The currentvoltage curves of d(A)12 and d(C)12 oligonucleotides were measured. Their differential electrical resistances were estimated and compared with each other.

In the construction industry, tests such as compressive strength, density porosity, and water absorption porosity are frequently used to determine material properties. In general, experimental studies are divided into two categories: destructive and non-destructive testing methods. According to the common consensus, destructive testing methods produce more dependable results than non-destructive testing methods. However, it is not possible to reuse the samples in destructive tests, and there are difficulties in taking samples from the building whose construction process has been completed. In addition, the experimental implementation of destructive tests creates time and cost disadvantages. Within the scope of this study, destructive and non-destructive experiments have been carried out on alkali-activated concrete composites, which have attracted interest as sustainable environmentally friendly composite building materials in recent years. Compressive strength, density, porosity, water absorption, etc. traditional test methods have been associated with electrical resistance measurements. Electrical measurements have been taken with the MEGGER equipment, and resistance values have been directly correlated with the other parameters. The positive results indicate that different structures of materials used in the construction industry can be evaluated regardless of sample size or localization.

The aim of this paper is to determine the influence of relative humidity on the comfort and electrical resistance properties of textile laminates in order to predict possible changes in footwear protection levels. Four textile laminates of different structure and fibre nature were selected for the study. It was determined that water vapour absorption of textile laminates strongly depends on the humidity of the storage environment. The absorption ability of laminates increases about 1.8 – 3 times as relative humidity increases from 65 % up to 95 %. The degree of increase depends on the textile laminate structure and the nature of the materials layers. The electrical properties of protective footwear can be influenced by the structure, thickness, relative humidity, and voltage of textile laminates. For textile laminates composed of natural and synthetic fibres and polymer foam as insulators, the resistivity increases with the thickness of the synthetic fibre and polymer layer. At low voltage (U = 100 V), the textile laminates tested became insulating materials, as the electrical resistivity exceeded the threshold values for antistatic materials in all relative humidity ranges. At high voltage (U = 500 V) the electrical resistivity of textile the laminates drops dramatically when the relative air humidity increases and the level of protection of the laminates depend on the amount of moisture absorbed and the nature of the layer materials. The laminates possessed insulating properties in environments of up to 65 % relative humidity. In a high humidity of the environment, the insulating properties of textile laminates turned to antistatic, except for laminate without a polymeric membrane, which became conductive.

This study explored the fascinating field of high-performance nanoscale metallic multilayer composites, focusing on their magnetic, optical, and radiation tolerance properties, as well as their thermal and electrical properties. In general, nanoscale metallic multilayer composites have a wide range of outstanding properties, which differ greatly from those observed in monolithic films. Their exceptional properties are primarily due to the large number of interfaces and nanoscale layer thicknesses. Through a comprehensive review of existing literature and experimental data, this paper highlights the remarkable performance enhancements achieved by the precise control of layer thicknesses and interfaces in these composites. Furthermore, it will discuss the underlying mechanisms responsible for their exceptional properties and provide insights into future research directions in this rapidly evolving field. Many studies have investigated these materials, focusing on their magnetic, mechanical, optical, or radiation-tolerance properties. This paper summarizes the findings in each area, including a description of the general attributes, the adopted synthesis methods, and the most common characterization techniques used. The paper also covers related experimental data, as well as existing and promising applications. The paper also covers other phenomena of interest, such as thermal stability studies, self-propagating reactions, and the progression from nanomultilayers to amorphous and/or crystalline alloys. Finally, the paper discusses challenges and future perspectives relating to nanomaterials. Overall, this paper is a valuable resource for researchers and engineers interested in harnessing the full potential of nanoscale metallic multilayer composites for advanced technological applications.

In recent years, there is a growing demand for materials that can both improve the mechanical properties of structures and carry out health monitoring and risk warning. In this case, in order to realize distributed deformation monitoring, a new method of making geogrid by 3D printing technology is proposed. The grille rib is made by embedding the conductive polymer (ground carbon fiber as conductive filler) into the insulating shell (PLA material) in the specified path, and then the rib is vertically crossed into each other to form a grille sample. In order to study the distributed deformation monitoring function of this grid, a manual push–pull testing machine was used to conduct a load–unload experiment to analyze the change rule of resistance on the grid plane. The following conclusions were obtained: the closer the ribs are to the load bearing point, the greater the change in resistance, and conversely, the farther the ribs are from the load bearing point, the smaller the change in resistance. Depending on the geogrid network characteristics, the electrical resistance distribution on the geogrid plane can be obtained by superimposing the resistance values of the horizontal and longitudinal ribs, then the location and the magnitude of deformation can be estimated. Additionally, this study carried out numerical simulation of the grid model based on ANSYS 15.0 software and compared with the loading experiment results to verify that the force deformation position can be retrieved through the change of resistance. [ABSTRACT FROM AUTHOR]

Conductive coatings on a glass substrate are widely used in electronics and automotive, ship, aircraft, and optical industries. The method for obtaining electroconductive polyacrylate coatings filled with bimetal Cu–Ni, Zn–Cu, or Zn–Ni particles and graphene nanoplatelets (GNPs) is developed in this work. At the ratio GNPs:bimetal powder:polymer of (33–35):(17–35):(30–50) (wt%) and the coating thickness 50 μm specific volume resistance is 0.12–0.26 Ω·cm owing to the percolation effect. Bimetal particles are synthesized by nickel or copper ions reduction from aqueous solutions on copper or zinc particles. Their composition is regulated by the duration of metal ions reduction. Bimetal particles have a structure of copper or zinc core with a loose shell of nickel or copper nanoparticles, they ensure the contact between GNPs forming a continuous network in polymer matrix. GNPs are obtained by thermal exfoliation of natural flake graphite treated in liquid ammonia containing metal sodium. Polymer composite is prepared using the solution of methyl‐ and n‐butylmethacrylate copolymer. Coatings have adequate adhesion to the glass, and owing to their high conductivity, absence of noble metals, simplicity and cheapness of fabrication can be used for production of conductive elements on glass and other substrates. Highlights: Cu–Ni, Zn–Cu, or Zn–Ni powder and GNPs filled conductive polyacrylate coatingsBimetal core‐shell particles are obtained by Ni(II) or Cu(II) reduction in solutionsBimetal particles and GNPs form a network in polymer with percolation effectSpecific volume resistance of coatings 50 μm thick on glass is 0.12–0.26 Ω·cmCoatings conductivity and adhesion to glass open great prospects for application [ABSTRACT FROM AUTHOR]

The chemical reaction of ion-adsorption-type rare earth ore during the in situ leaching process is accompanied by ion migration and charge movement, making the leaching process electrochemical in nature. The chemical reaction rate plays an important role in the leaching rate of rare earth elements. In this work, electrochemical impedance spectroscopy (EIS) was used to reveal the characteristics of electrical resistance alterations and leaching rate of rare earth elements during in situ leaching. The equivalent circuit model of the leaching process was established, and two critical parameters of solution resistance Rs and charge transfer resistance Rt were analyzed to reflect the electrochemical characteristics. According to the characteristics of electrical resistance alteration, the leaching process was divided into four stages: wetting, reaction, equilibrium, and top water stage. The resistance parameters Rs and Rt decreased first and then increased during the leaching process. The maximum value of Rs was 1330 Ω∙cm2 at the end of the top water stage, and the minimum value was 125 Ω∙cm2 at the beginning of the equilibrium stage. The maximum value of Rt was 8310 Ω∙cm2 at the beginning of the leaching stage, and the minimum value was 21 Ω∙cm2 at the end of the reaction stage. Rs and Rt were negatively correlated with the pore size and chemical reaction rate during leaching. With an increasing pore size and reaction rate, the resistance parameters decrease. This study provides a new idea for the intelligent monitoring of rare earth ore. [ABSTRACT FROM AUTHOR]

The results of work on the creation of an efficient and economical method, as well as the manufacture and testing of an installation for non-destructive quality control of baked anodes of aluminum electrolytic cells. The installation uses the method of measuring the electrical resistance of the anode and building its calculation model with known data on its geometry and resistivity, as well as the geometry and coordinates of internal defects. In this case, a series of calculations is performed to obtain a 3D matrix of amplitudes and directions of the vectors of the calculated strengths or inductions of the electromagnetic field at points located near the outer surface of the anode. To do this, at least two electrically conductive contacts are placed at these points, passing a given amount of electric current through the anode. Also, at least one sensor is placed near the outer surface of the anode and the amplitude and direction of the magnetic field intensity or induction vectors are measured and displayed in the form of a 3D matrix of the measured intensity or magnetic field induction vectors. After that, the 3D matrices of the calculated and measured vectors of the strength or induction of the magnetic field are compared at the same points located near the outer surface of the anode and, based on these results, the sizes and coordinates of internal defects are determined. The technical result of the implementation of the proposed method is to increase the accuracy, reliability and reliability of determining the location of defects in baked anodes. The installation was tested in laboratory and industrial conditions, which showed good agreement between the results obtained and the data obtained by destructive testing. The entire procedure for checking the quality of one anode took 45–50 s. As a result of preliminary tests, it was determined that out of 100% of the anodes approved for use by the manufacturer, 13.5% were rejected by NDF testing. During research in the Siberian Federal University laboratory, it was found that the accuracy of detecting defective anode blocks using NDF was 82%. Industrial test results of the installation made it possible to divide all anode blocks into 4 classes based on quality, and the validity of this division was confirmed by destructive testing tests. [ABSTRACT FROM AUTHOR]

The aim of this work was to synthesize and investigate the roentgenographic and electro-physical properties of new phases, namely double tellurites of neodymium. Oxotellurites of the composition NdMeIITeO4.5 MeII - Ca, Ba) were synthesized by the method of ceramic technology with high-temperature interaction of Nd2O3, TeO2 oxides with carbonates of alkaline earth metals in the interval of 800°C - 1200°C . Roentgenograms of the synthesized compounds were obtained using an Empyrean powder diffractometer by PANalytical and indication was determined using the X'Pert HighScore Plus program. It was found that the synthesized tellurites were crystallized in tetragonal syngony. The unit cell parameters, roentgen and pycnometric densities of the compounds were determined. It was revealed that with increasing ionic radii from Ca to Ba, the lattice parameters and unit cell volumes of synthesized tellurites increase. The assumed structure of the synthesized double tellurites of neodymium is a distorted perovskite structure. A study of the temperature dependence of the dielectric permittivity and electrical resistance of tellurites of neodymium-alkaline earth metals established that they can possess semiconducting properties at 293 K - 483 K. Temperature coefficients of resistance and forbidden zone width of tellurites were calculated. [ABSTRACT FROM AUTHOR]

Copyright of Industria Textila is the property of Institutul National de Cercetare-Dezvoltare pentru Textile si Pielarie and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Flexible transparent electrodes are integral to the advancement of flexible optoelectronic devices such as flexible displays and solar cells. However, indium tin oxide (ITO), a traditional material used in transparent electrodes, exhibits a significant increase in resistance under mechanical stress, which limits the long-term stability of flexible devices. Here, we prepare various types of silver nanowire (AgNW)-based transparent electrodes and investigate their stability in terms of electrical resistance and optical transmittance under compressive and tensile stresses. Under compressive stress, ITO on a polyethylene terephthalate (PET) substrate exhibits a significantly high electrical resistance of >3000 Ω after 1000 stress cycles, while the AgNW-coated electrode on a PET film exhibits a relatively smaller resistance of <1200 Ω. The AgNW-embedded electrode in a UV-curable polymer matrix (NOA63 or NOA71) exhibits an even lower electrical resistance of <450 Ω because AgNWs can easily maintain their network. A similar trend is observed under tensile stress. The AgNW-embedded electrode shows the highest resistance stability, whereas the ITO on the PET substrate shows the poorest stability. The optical transmittance is comparable regardless of the type of stress or electrode used. This superior stability of the AgNW-based electrodes, realized by integrating it with a polymer matrix, is promising for the development of durable and high-performance flexible optoelectronic devices. [ABSTRACT FROM AUTHOR]

Waste fly ash (WFA) and secondary aluminum dross (SAD) are common solid wastes inducing environmental pollution. These materials contain certain active substances that can be used in cement-based materials. Therefore, cement concrete can be used to solidify these solid wastes. In this study, the influence of the assembly unit of secondary aluminum dross (SAD) and waste fly ash (WFA) on the properties of ultra-high-performance concrete (UHPC) is investigated. The slump flow, the plastic viscosity, the yield shear stress, and the initial setting time of fresh UHPC are measured. Moreover, the flexural and compressive strengths and the dry shrinkage rate (DSR) are determined. The electrical resistance and reactance are tested. The electron microscopy spectroscopy (EDS), thermogravimetric analysis (TG), and X-ray diffraction spectrum (XRD) curves are obtained for revealing the mechanism of macroscopic performances. Results show that due to the optimal specific surface area and the volcanic ash effect, the UHPC with the assembly unit of 50% SAD and 50% WFA provides the highest slump flow, DSR, and mechanical strengths, while the corresponding plastic viscosity, yield shear stress, and electrical resistance are the lowest. The SAD can delay the setting time of UHPC. The relationship between the electrical resistance or the electrical reactance and the mass ratio of SAD accords with the quadratic function. The corresponding electrical resistance is the lowest. The relationship between the mechanical strengths and the electrical resistance fits with the cubic function. The leaching amounts of Zn and Cr increase in the form of cubic function with the immersing time. Meanwhile, the SAD can decrease the Zn and Cr by 0%–46.3% and 0%–45.2% respectively. As obtained from the EDS results, the element of Al is increased by adding SAD. The XRD curves show that the crystals of Al2O3 are increased and the SiO2 crystals are decreased by the added SAD. UHPC with 50% SAD exhibits the highest compact microstructures and the least Ca(OH)2 and 3CaO·SiO2 hydration products. The TG results show that UHPC with 50% SAD shows the lowest TG values of all the groups. This research will provide new UHPC materials and techniques applied in solidifying the WFA and SAD in the future. [ABSTRACT FROM AUTHOR]

The electrical properties and kinetic dependences of thermally induced drift of electrical resistance in eco-friendly single- and multilayer temperature-sensitive thick-film structures based on Cu0.1Ni0.1Co1.6Mn1.2O4 (with p+-type electrical conductivity) and Cu0.1Ni0.8Co0.2Mn1.9O4 (with p-type of electrical conductivity) ceramics for multisensor nanosystems. It has been established that in the p- and p+-type thick films the processes of burning out the residues of the organic bond between grain spinels and simultaneous penetration of metallic silver into the space are activated. Such processes are described by a compressed exponential-power relaxation function. Thick-film p+-p structures are characterized by own aging processes, which manifest themselves in an increase in electrical resistance. Kinetics of their thermally-induced aging is adequately described by an extended exponential-power function. [ABSTRACT FROM AUTHOR]

Copyright of Duzce University Journal of Science & Technology is the property of Duzce University Journal of Science & Technology and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

One significant form of deterioration in weathering steel bridges is corrosion, and steel requires water and oxygen to corrode. As a measurement method for the wetness time of the rust layer on weathering steel, measuring electrical resistance has been proposed. In this research, the fundamental data have been collected as preliminary considerations to develop this method of measuring water retention in the rust layer. Based on the measurement of specimens, it is revealed that measuring the exact amount of water retention is difficult because electrical resistance depends on the thickness of the rust layer and the supplied amount of NaCl. Thus, the water retention ratio is calculated by dividing the mass of the water-retained specimen by the mass of the full water-retained specimen. These measurement results suggest a potential method for predicting water retention ratio by measuring electrical resistance and rust thickness. The approximate water retention ratio is predicted by plotting electrical resistance and rust thickness in the proposed diagram. [ABSTRACT FROM AUTHOR]

We measured the temperature dependence of the resistance in thinned samples of a layered transition metal dichalcogenide 1T-TiSe2. As a result, a thermal hysteresis of resistance was discovered in most samples with a thickness of 10 μm or less, but not in samples thicker than 100 μm. The onset temperature of this hysteresis was almost the same as the onset temperature of the charge density wave (CDW) transition, suggesting that this hysteresis is related to the CDW. All the samples with hysteresis exhibited one or a few jumps of resistance in the 110–190 K range in cooling. Moreover, the hysteresis was related not only to the history of temperature below the CDW transition temperature, but also to that above the transition temperature. To interpret these anomalous results, we discuss the effect of impurities on the domain structure of the CDW. [ABSTRACT FROM AUTHOR]