Modern Testing Techniques Research Articles

Magneto acoustic emission technique: A review of methodology, applications, and future prospects in non-destructive testing

The magneto acoustic emission (MAE) technique is an emerging non-destructive testing (NDT) method that has shown potential for defect detection in the bulk of material, proven vital for the safety and integrity of the material. The MAE technique has shown promising results among modern non-destructive testing techniques for ferromagnetic materials. Although MAE technique is a long-established NDT method, it has the potential for further development. This paper provides an in-depth review of MAE signals' physical origin and characteristics, compares them with their counterpart, Magneto Barkhausen Noise (MBN), and explores data acquisition methods and applications, including specific case studies in material defect detection. The research gaps in the MAE technique are discussed, and the paper explores potential developments, highlighting future perspectives and possible improvements.

Modern Microbiological Methods to Detect Biofilm Formation in Orthopedy and Suggestions for Antibiotic Therapy, with Particular Emphasis on Prosthetic Joint Infection (PJI).

Biofilm formation is a serious problem that relatively often causes complications in orthopedic surgery. Biofilm-forming pathogens invade implanted foreign bodies and surrounding tissues. Such a condition, if not limited at the appropriate time, often requires reoperation. This can be partially prevented by selecting an appropriate prosthesis material that prevents the development of biofilm. There are many modern techniques available to detect the formed biofilm. By applying them we can identify and visualize biofilm-forming microorganisms. The most common etiological factors associated with biofilms in orthopedics are: Staphylococcus aureus, coagulase-negative Staphylococci (CoNS), and Enterococcus spp., whereas Gram-negative bacilli and Candida spp. also deserve attention. It seems crucial, for therapeutic success, to eradicate the microorganisms able to form biofilm after the implantation of endoprostheses. Planning the effective targeted antimicrobial treatment of postoperative infections requires accurate identification of the microorganism responsible for the complications of the procedure. The modern microbiological testing techniques described in this article show the diagnostic options that can be followed to enable the implementation of effective treatment.

Study on the fracture mechanical properties of high performance concrete (HPC) with rapid cooling after high temperature

In practical engineering, concrete structures typically undergo high temperatures and fire spray cooling during the process of fire, and high temperatures will cause changes in the microstructure of concrete. Therefore, studying the fracture mechanical properties of concrete after rapid cooling at high temperatures is more in line with the actual engineering situation. This paper sets five temperature conditions (20°C, 200°C, 400°C, 600°C, and 800°C), and after rapid cooling in a water bath, a hydraulic servo machine is used to conduct three-point bending beam fracture tests on plain concrete (PC) and high performance concrete (HPC). The fracture process and mechanism are analyzed using digital image correlation (DIC) and acoustic emission (AE). The research results indicate that the three-point bending unstable fracture load of PC and HPC decreases with the increase of temperature, with the maximum reduction after 800 ℃ high temperature, reaching 87.5% and 82.2%, respectively. After high temperature, the fracture energy of PC and HPC both showed a trend of first increasing and then decreasing. The ductility index of PC and HPC increases with the increase of temperature. The unstable fracture toughness and initial fracture toughness of PC and HPC decrease with the increase of temperature. By combining DIC and AE technologies, the development and fracture mode of cracks in PC and HPC after rapid cooling at high temperature are analyzed. The results showed that the softening effect of concrete is more significant after high temperature, the crack initiation stage is earlier, and the bearing capacity is lower. Furthermore, modern testing techniques are employed to reveal the mechanism of the impact of high temperature and cooling methods on the mechanical properties of HPC from a microscopic perspective. The research results have important reference value for practical engineering.

Chameleon-like Response Mechanism of Gold-Silver Bimetallic Nanoclusters Stimulated by Sulfur Ions and Their Application in Visual Fluorescence Sensing.

Herein, 2-mercapto-5-benzimidazolesulfonate acid sodium salt dihydrate (MBZS)-protected gold-silver bimetallic nanoclusters, named MBZS-AuAg NCs, were synthesized. Interestingly, we found that MBZS-AuAg NCs solutions can exhibit different fluorescence color changes under sulfide stimulation. A series of modern analytical testing techniques were used to explore the interaction mechanism between MBZS-AuAg NCs and sulfide. Sulfide ions can not only cause MBZS-AuAg NCs to exhibit rich fluorescence color changes similar to those of a chameleon but also have four linear relationships between the response intensity and sulfide concentration. A wide-range sulfide fluorescence sensing platform was constructed based on four linear segments with different fluorescence color responses. This sensing platform can be directly used for the determination of S2- with a detection limit as low as 11 nM. The portable test paper based on MBZS-AuAg NCs can realize the visual and rapid detection of gaseous hydrogen sulfide with a detection limit of 100 ppb (v/v). The wide detection range of the proposed method not only allows it to be used as an alternative method for sulfide detection in environmental samples but also has potential applications in the rapid detection and early warning of hydrogen sulfide gas in industrial and mining scenarios.

Modulating adhesion strength in multi-ferroic composite materials: Insights from adhesive contact with arbitrary profile indenters

Adhesion control is a critical aspect of various applications, from industrial adhesion devices to the locomotion of insects on ceilings and walls. Multi-ferroic materials, which encompass mechanical, electrical, and magnetic properties, offer approaches for reversible adhesion control. This study presents a comprehensive theoretical framework for adhesive contact in multi-ferroic composite materials when subjected to axisymmetric rigid indenters with arbitrary profiles. We analytically derive the physical fields for various contact models, including Hertz contact, Johnson–Kendall–Roberts (JKR), and Maugis–Dugdale (MD) adhesive models. The obtained energy release rates indicate that the electric and magnetic potentials can modulate adhesion strength. The Griffith energy balance relation is employed to derive the indentation forces and penetration depths, which can be extended to a range of common indenters. Notably, the classical approximations fail when using small spherical indenters, but the study provides valid alternatives. The influence of amplitude and wavelength on contact behavior is explored, with greater effects observed for larger or smaller values. For cosine-shaped indenters, equivalence to flat-ended cylindrical punches is established under specific conditions. The study also reveals that the power indices for power-law-shaped indenters change the influence of electric and magnetic potentials on pull-off forces. These findings provide a theoretical fundament associated with the biomimetic and artificial adhesive systems and the modern testing techniques.

Integrity assessment of a crack inside a pressure vessel wall in RHPP “Bajina Bašta”

The goal of this research was to combine non-destructive test methods, specifically modern ultrasound testing techniques with numerical simulations via finite element method, to determine the risk of failure of a pressure vessel in the reversible hydropower plant “Bajina Bašta”. Using Phased Array Ultrasonic Technique and Time of Flight Diffraction technique, a crack with a length of 75 mm and depth of 20 mm was detected inside the pressure vessel wall, in the vertical welded joint. Based on the exact position and size of the crack, a numerical model was made in ABAQUS. Two models were made, with and without the crack, for comparison purposes. Since the obtained results did not show difference, it was decided to make another model, with different boundary conditions, providing a more realistic insight into the behaviour of the pressure vessel, which still remained in the safe zone.

The Application of Heat-Shrinkable Fibers and Internal Curing Aggregates in the Field of Crack Resistance of High-Strength Marine Structural Mass Concrete: A Review and Prospects.

High-strength large-volume marine concrete is a critical material required for the construction of large-span sea-crossing bridges. However, the widespread issue of cracking in this concrete type significantly impacts the durability and load-bearing capacity of concrete structures. Dealing with these cracks not only delays construction schedules but also increases project costs. Addressing these pressing technical issues, this project proposes the use of newly developed high-modulus heat-shrinkable fibers (polyethylene terephthalate fiber, also known as PET fiber) from the textile industry. These fibers utilize the heat generated during the hydration of large-volume concrete to trigger its contraction, applying three-dimensional micro-prestressing stress to enhance its crack resistance, while simultaneously incorporating prewetted aggregates with high-performance micro-porous structures and utilizing their internal curing effect to reduce concrete shrinkage. This helps to minimize the loss of micro-prestressing stress caused by concrete shrinkage and creep. This synergistic approach aims to improve the crack resistance of high-strength large-volume marine concrete. By employing modern testing and simulation analysis techniques, this study aims to uncover the mechanism by which the heat-shrinkable fibers exert micro-prestressing stress on concrete and the water release mechanism of internal curing aggregates during the temperature rise and fall stages of large-volume concrete. It seeks to elucidate the cooperative regulation of the microstructure and performance enhancement mechanisms of high-strength large-volume marine concrete by the heat-shrinkable fibers and internal curing aggregates. This research will lead to the development of novel methods for the design and crack control of high-strength large-volume marine concrete, which will be validated through engineering demonstrations. The outcomes of this study will provide theoretical foundations and technical support for the preparation of the crack-resistant large-volume marine concrete used in large-span bridges.

Performance evaluation and multiscale investigation of deodorant on mechanism of rubber modified asphalt

Asphalt fume emission caused by high-temperature is large during the production and construction of rubber modified asphalt, and the toxic and odor gas contained seriously pollutes the environment. This paper prepared rubber modified asphalt (RMA) and deodorant rubber modified asphalt (DRMA) and evaluated the impact of deodorants on the environmental and physical properties. Modern testing techniques, such as gel permeation chromatography, are used to explore the microscopic morphology of RMA, DRMA, and crumb rubber extracted from RMA and DRMA, so as to reveal the mechanism of deodorant in asphalt. Meanwhile, the effect of deodorant was monitored from macro scales by applying electrochemical sensing technology. The results show inhibiting the degradation of rubber in asphalt is the main mechanism of deodorant. Deodorant can not only promote the swelling of rubber in asphalt and improve the stability of sulfur elements, but also capture the odor particles in asphalt fume, reduce the concentration of polluting organic and H2S, realize the application of rubber modified asphalt environmentally-friendly, and promote the recycling of waste tires and the sustainability of pavements for pollution and carbon reduction.

Genetic differences in variants of the AMD virus at the site of a disease outbreak

Aleutian Mink Disease Virus (AMDV) results in mink breeding losses due to frequent abortion, low fecundity and high juvenile mortality. Due to the high persistence of pathogen in the environment and lack of causative treatment there is a need for research on alternative methods to eliminate the pathways of the spread of the virus and extinguish current outbreaks. The aim of the study was to investigate molecular variation of AMDV on a farm where mass deaths of mink took place.The material for the research was obtained from a mink farm located in Latvia. Mass deaths had occurred on the farm among symptoms typical of Aleutian disease. Spleen samples were collected from the dead animals during post-mortem examination. Sequencing and bioinformatic analysis made it possible to distinguish the variants occurring in the groups.The presence of the genetic material of the virus was confirmed by PCR and qPCR in each of the spleen samples. The isolates were divided into two main groups: the dominant group A, with more than 83% of all isolates, and group B. Comparison of the variants with the nonpathogenic strain AMDV-G revealed that isolates from group A were more than 95% similar to that strain, whereas the similarity of group B isolates was just over 86%. The average viral load in both groups was 108 copies; no differences in viral load were noted between groups.Testing based on serological analysis produces fairly effective screening results, but these methods do not enable complete elimination of the virus from a population. Only their use in combination with modern testing techniques as tools for identification of vectors and the directions of the spread of the AMD virus can make it possible to block the routes of its spread and to extinguish its current outbreaks.

Study on Structure and Anti-UV Properties of Sericin Cocoons

Abstract Through biogenetic engineering, the posterior silk glands of Bombyx mori larvae are degenerated, and only the middle silk glands are retained to secrete sericin to produce sericin fibers, so as to obtain sericin cocoons with high sericin content (>98.5%). For this paper, sericin cocoons were studied, and the morphological structure characteristics and properties of sericin cocoons and common Bombyx mori cocoons were compared and analyzed through such modern test techniques as SEM, FTIR, and XRD. Results show that sericin cocoons have the basic morphological structure of cocoons, but because of the brittleness and hardness of sericin, the ssericin cocoons have poor integrity with a thermal decomposition rate that is higher than that of cocoons; the two cocoons are of a similar protein structure, with both α-helix and β-sheet structures, and dominantly the β-sheet structure; and the crystallinity of sericin cocoons (10.48%) is lower than that of the common Bombyx mori cocoons (27.10%). Sericin was extracted from both cocoons to obtain a mixed sericin solution respectively, which were coated on base fabrics of polyester taffeta (210T) for coating finish and subjected to qualitative research for their anti-UV properties. The base fabrics coated with mixed sericin solutions of sericin cocoons and Bombyx mori cocoons have an anti-UV performance index (UPF) of 23.9% and 22.5% respectively, which are higher than that of the base fabric (8.9%)..

Structure and optical band gap of porous nano-Cu-SiC composite films prepared via magnetron sputtering

Porous nano-Cu-SiC composite films were prepared using double-target co-sputtering technology combined with annealing process by using high-purity copper and SiC as target materials, methane and nitrogen as the reaction gas, and argon as the working gas. The surface morphology, crystal structure, and optical transmission properties of the composite films were characterized and analyzed using modern testing and analytical techniques. The results show that the prepared composite film has a uniform and porous microstructure. Further analysis shows that SiC was dispersed in the copper matrix and well combined with the copper matrix. Annealing was conducive to carrier transmission. After annealing, the composite films recrystallized and grew again, thus increasing the stability of the structure. Raman spectra show that annealing can lead to the separation and crystallization of silicon and carbon phases in composite films. With the increase of energy density, the crystallization degree of porous SiC increases continuously, and the crystallization quality of the composite film and the light transmittance are improved. The prepared porous nano-Cu-SiC composite films have semiconductor properties, and the optical band gap is 0.17 eV. The porous nano-Cu-SiC composite films prepared using this method have good application prospects in high-performance composite film materials, such as heat conduction and wave absorption.

Three elements of liquefaction risk of liquefiable solid bulk cargoes during sea transport: Critical review

The transport of liquefiable solid bulk cargo is one of the main causes of maritime safety accidents over the past decade. This article innovatively summarized the status quo of research on the liquefaction risk of liquefiable solid bulk cargo during sea transport from three aspects, namely, the properties, moisture content and external induced load of cargoes during their sea transport. The influence of the main physical parameters, the application of modern testing techniques (e.g., transparent soil and PIV) in related fields, and various TML testing methods in IMSBC code were also introduced. Result highlighted external induced load as an important factor affecting the cargo liquefaction during sea transport. The latest trends on the adoption of the liquefaction risk assessment method based on external load were also systematically introduced, and the importance of quantitative risk assessment in practical application was emphasized. This article also analyzed the main challenges encountered in managing liquefaction risk and revealed quantitative risk assessment and liquefaction mechanism as the main trends in related research. Four promising directions for future research were also put forward, which can provide valuable ideas for researchers and managers to further study and control the liquefaction risk of liquefiable solid bulk cargo.

Catalytic performance of amino acid/phosphotungstic acid as bi-functional heterogeneous catalyst for biodiesel production

In this study, a series of acid-base bi-functional catalysts were prepared by mixing different amounts of basic amino acids (AAs) and phosphotungstic acid (PTA), which exhibited the excellent performance in catalyzing conversion of oleic acid (OA) for the biodiesel production. The physicochemical properties of the catalysts were characterized and analyzed using modern testing techniques and characterization methods such as XRD, FT-IR, XPS, SEM, TEM, and Hammett titration. The various influence parameters were optimized using the central composite design based the response surface methodology, where the maximum biodiesel yield of 97.0% was achieved at the MeOH/OA molar ratio of 5.9, the catalyst loading of 8%, reaction time of 6 h, and reaction temperature of 65℃. Furthermore, the stability and reusability of the prepared catalyst were also demonstrated. At last, the possible catalytic mechanism of the prepared catalyst was comprehensively described.

Review on miniaturized flexible wearable antenna with SAR measurement for body area network

The existence of Body area network (BAN) is present at the proximity of human body comprising of gadgets put in, on and close with regard to person’s body. This BAN is comprising of embedded devices which communicate information through different channel to other devices. Basically, these devices utilize electromagnetic innovations for making device handier and more useful. It can be broadly seen as this could be utilized in three different manners. The application of BAN is truly valuable in many different medical applications. First is in observing the sensors’ performance which has been inserted inside the body of patients. Second is following record of wellbeing of older folks. Third is many modern testing techniques such as MRI, CT-Scan, endoscopic test etc. BAN is being used in so many useful functions. It’s an obtrusive, low power and handy system comprising of high data security. Looking at the usefulness of the wearable antennas under BAN. In the presented study a review on various aspects required to be gone through while designing antenna to work in BAN. and various methods to get minimum errors by discussing different configurations of MSP (Micro strip patch) has been discussed. Through this review paper the designing and analysis of various body worn antennas applicable in BAN working under different situations has been done which is really helpful in construction of wearable flexible antenna for BAN.

Investigation on the mechanism and performance of asphalt and its mixture regenerated by waste engine oil

Waste engine oil (WEO) is planned to be used as a regenerating agent for asphalt pavement materials to regenerate the reclaimed asphalt pavement (RAP) and recovery their road performance. To enhance the modification effect of WEO on the road performance of asphalt mixture, the furfural extraction oil and epoxy resin are added to compound with the WEO as well. The modern testing techniques were used to reveal the mechanism of WEO-RA from the microscopic scale. The macroscopic properties of asphalt such as the physical, rheological and anti-aging properties of asphalt were investigated to study the regeneration effect of WEO on the technical performance of aged asphalt. The road performance and mechanical properties of recycled asphalt mixtures were investigated extensively. The results show that WEO can be used to recovery the aged asphalt by modifying its components, the modification of WEO on aged asphalt is a physical way. The thermal stability of WEO regenerated asphalt (WEO-RA) is slightly worse than that of the original asphalt, but the WEO-RA has good thermal stability. Physical and high-temperature rheological performance of WEO-RA is almost the same with original asphalt. The low-temperature property rheological performance WEO-RA is two PG better than that of original asphalt. The long-term anti-aging performance of WEO-RA is as good as original asphalt. The performance of WEO-RA has good storage stability. The asphalt mixtures with 0–50% RAP meet the road performance requirement, what’s more, the both the high-temperature and low-temperature performance of asphalt mixture are enhanced with different contents of RAP regenerated by WEO.

Study of the anti-abrasion performance and mechanism of coral reef sand concrete

In a marine environment, tidal waves carry coral reef blocks, which cause erosion and abrasion of breakwaters and other concrete structures, seriously affecting their stability and durability. In order to reveal the damage mechanism of coral reef sand concrete, herein the effects of admixtures such as fly ash, silica fume, polypropylene fiber and basalt fiber on the anti-abrasion performance and micro-hardness of coral reef sand concrete were studied. Additionally, the mechanisms of the abrasive damage and the increased performance of coral reef sand concrete were revealed by means of modern testing techniques, including X-ray diffraction and scanning electron microscope. The results revealed a linear relationship between the anti-abrasion strength and the compressive strength of the coral reef sand concrete mixed with fly ash and silica fume; whereas this correlation was not observed for the coral reef sand concrete containing fibers. Unlike ordinary aggregates, the characteristics of the coral aggregate such as the roughness, porosity, susceptibility to breakage, the irregularity of the shape, and the mineral composition were found to affect the anti-abrasion performance of the coral reef sand concrete. The roughness and the porous characteristics improved the micro-hardness of the aggregate-cement stone joints (0 μm) in the coral reef sand concrete, but there was still a weak Interfacial transition zone. Moreover, it was observed that the abrasion of the coral reef sand concrete can be reduced by the presence of a strong and dense interfacial transition zone, the crack resistance effect of the fibers, and the enhanced cohesive force of the cement mortar and fibers.

Genetic phenocopies of cerebral palsy: a review

Cerebral palsy (CP) represents a heterogeneous group of non-progressive disorders of motor development and posture control, leading to activity limitation due to disturbances in a fetal or infant’s developing brain. In CP, motor impairment is often accompanied by disturbances of sensation, cognition, communication, perception, and (or) behavior, and (or) by a seizure disorder. Despite profound knowledge of the CP risk factors, in many patients, the latter cannot be identified, and the neuroimaging features of the brain injury may also be absent. Those patients, at least in part, can include children with undiagnosed genetic phenocopies of the CP. Literature search was performed using Scopus, Web of Science, PubMed (MEDLINE), and eLibrary databases. In the review, we briefly touch upon the current understanding of CP’s risk factors and pathophysiology. Common neuroimaging findings typical for CP subtypes are presented. We then discuss the role of genetic factors that can lead to the development of CP phenocopies, briefly describing their phenotypic subtypes and some of the specific diseases. Clinical and neuroimaging «red flags» that can prompt a diagnostic search for genetic disorders are reviewed. The role of modern genetic testing techniques, including high-throughput sequencing, in diagnosing CP phenocopies is described. We present a general diagnostic approach to suspected genetic CP phenocopies. Early identification of the pediatric population’s genetic conditions can affect the individual and family prognosis and the patient’s management.

Attitude toward personal genomics: A nation‐wide survey of public and professionals in Pakistan

With the emergence of modern genetic testing and profiling techniques, it has become imperative to assess the general public awareness and attitudes toward such developments. The public's perspective and possible responses are necessary for planning commercial, legal, medical, or healthcare initiatives. The purpose of this study was to assess the perception of the general public and professionals about the personal genome testing and genetic profiling. A questionnaire-based survey was conducted to investigate the attitudes of 2954 adults (56.4% male and 43.6% female) from more than 120 different educational, research, and professional organizations of Pakistan. The aim of the study was to assess interest in genomic testing. The findings of this survey will feed into the larger Genome Projects in Pakistan and will be helpful for the national bioethical committee, healthcare agencies, diagnostic companies, and other institutions for making policy decisions.

Local structure modification for identifying the site preference and characteristic luminescence property of Eu2+ ions in full-color emission phosphors Sr18Mg3(PO4)14:Eu2+

An understanding on the site preference of luminescence centers in phosphors serves as a starting point to illustrate the relationship between structure and luminescence. Till now, various methods such as theoretical calculation or modern testing techniques are employed to analyze their luminescent behavior and intrinsic mechanism. The present study proposes a local structure modification method to confirm the site occupation of Eu2+ ions in a whitlockite-type phosphor Sr18Mg3(PO4)14: Eu2+. The result shows that Eu2+ ions can not only occupy Sr2+ sites but also substitute partial Mg2+ sites in Sr18Mg3(PO4)14. Owing to this, three emission bands centered at 420 (blue), 520 (green) and 620 nm (red) are simultaneously observed upon ultraviolet light excitation, resulting in a full color emission in Sr18Mg3(PO4)14: Eu2+ phosphors. Meanwhile, the detailed structure information of Sr18Mg3(PO4)14 are renewedly evaluated and the optical spectroscopy property, decay curves and thermal quenching behavior as well as related mechanism of Sr18Mg3(PO4)14: Eu2+ are studied in detail. Finally, an ultraviolet light pumped white LED is fabricated with suitable CCT of 4663 K and high Ra of 82. The current analysis provides a deep insight into the origin of Eu2+ luminescence and its relationship with local lattice environment, which paves a new avenue to identify the site preference of luminescence centers.

Detection of disbonds in adhesively bonded aluminum plates using laser-generated shear acoustic waves

Adhesively bonded metals are increasingly used in many industries. Inspecting these parts remains challenging for modern non-destructive testing techniques. Laser ultrasound (LU) has shown great potential in high-resolution imaging of carbon-reinforced composites. For metals, excitation of longitudinal waves is inefficient without surface ablation. However, shear waves can be efficiently generated in the thermo-elastic regime and used to image defects in metallic structures. Here we present a compact LU system consisting of a high repetition rate diode-pumped laser to excite shear waves and noncontact detection with a highly sensitive fiber optic Sagnac interferometer to inspect adhesively bonded aluminum plates. Multiphysics finite difference simulations are performed to optimize the measurement configuration. Damage detection is performed for a structure consisting of three aluminum plates bonded with an epoxy film. Defects are simulated by a thin Teflon film. It is shown that the proposed technique can efficiently localize defects in both adhesion layers.