Deformation Vibrations Research Articles

Spectroscopic studies of conformational polymorphism in 4-methylphenol

In this work, conformational polymorphism in 4-methylphenol has been studied using a Fourier-transform infrared (FTIR) spectroscopy. The first time we have received the FTIR spectra of the stable and two metastable phases of 4-methylphenol and their temperature dependencies at temperatures from 300 to 12 K in the spectral region of the methyl group (CH3) deformation vibrations. Analysis of the FTIR spectra showed that there are significant differences in the position and shape of the bands related to the deformation bending β(CH3) and rocking ω(CH3) vibrations when passing from one polymorph to another. A particular feature of the methyl group in the 4-methylphenol molecule is that it does not take part in hydrogen bonding interaction. This made it possible to relate the observed changes in the FTIR spectra with changes in the geometrical parameters of the 4-methylphenol molecule. This in turn allowed us to conclude that the polymorphs under study consist of different conformers of 4-methylphenol molecule.

Evaluation of Nanocrystalline Magnetic ErFeO3 Composite for the Sorptive Removal of Cesium and Cobalt Ion from Aqueous Solution

The effect of nano-scale size in the magnetic semiconductor rare Earth ferrite system, ErFeO3, has been studied. The orthorhombic crystal structure in the nano-scale was found for ErFeO3 prepared by the sol-gel method to be 8 nm. Fe-O stretching vibration was identified in the IR band at around 561 cm−1, whereas the O-Fe-O deformation vibration was identified in the band at about 437 cm−1. The semiconducting behavior of ErFeO3 was found, and its energy gap equals 1.75 eV. As the frequency increases, the charge transport mechanism showed transition from the small polaron model, dominated by thermally activated hopping, to a quantum mechanical tunneling model, where charge carriers move through the material by tunneling between localized states without trapping. This transition is driven by the charge carriers having less time to become localized at higher frequencies, allowing for more direct tunneling transport. The new application of nano-crystalline ErFeO3 to remove hazardous elements was evaluated. The adsorption isotherm of Cs(I) and Co(II) by ErFeO3 nanocomposite was studied. The findings of the present studies highlight the potential use of ErFeO3 as a new, efficacious sorbent for removing Cs(I) and Co(II) from the waste stream, providing a reliable and efficient solution to environmental pollution.

Obtaining Microcellulose from Solid Agro-Waste by Ball Mill Assisted by Light Acid Hydrolysis Process.

Cellulose, the most abundant biopolymer on Earth, is biodegradable, nontoxic, and derived from renewable sources. Its properties and applications depend on the extraction methods and sources, making plant waste reuse a sustainable production option. This study aimed to assess the potential of cowpea pod skin (Vigna unguiculata) as a source of microcellulose (CPMC) using a chemical-mechanical process involving ball milling combined with acid hydrolysis. For a comparative analysis of the method's efficiency and biomass performance, corn straw (Zea mays L., CSMC) and pineapple peel (Ananas comosus, PPMC) were also utilized as extraction sources. The chemical composition of microcelluloses (MCs) was investigated by Fourier Transform Infrared Spectroscopy (FTIR), thermal behavior by Thermogravimetric Analysis (TGA), crystallinity by X-ray Diffraction (XRD), morphologies by Scanning Electron Microscopy (SEM), and shape and size by Atomic Force Microscopy (AFM). In the FTIR spectra, absorption bands characteristic of cellulose were observed at 3408 cm-1 (hydroxyl group OH stretching), 1640 cm-1 (adsorbed water molecules), 1205 cm-1 (O-H deformation vibration), 1165 cm-1 (C-O-C- stretching vibration), 1113 cm-1 (glucose ring stretching vibration), 1055 cm-1 (CO stretching), 1028 cm-1 (C-OH stretching), and 895 cm-1 (β-glycosidic bonds). The TGA/DTG curves of all the samples showed three stages of mass loss, and CPMC proved to be the sample with the greatest thermal stability. The crystallinity indices of the MCs samples ranged between 69.23-75%. The micrographs show compact and lamellar materials. However, AFM measurements revealed distinct nanostructures for each of the MCs obtained, displaying lamellar structures from 20 to 280 nm. Therefore, this method was efficient for extracting MCs from different types of biomass. The analyses demonstrated greater efficiency in the CPMC and CSMC samples. In this context, they have become promising candidates for application in a wide range of industrial materials.

Low-Coherence Integrated Optical Interferometer for Fibre Optic Sensors.

This paper proposes and implements a novel scheme for recording signals from fibre optic sensors based on tandem low-coherence interferometry with an integrated optical reference interferometer. The circuit allows precision control of the phase shift. Additionally, the paper illustrates the potential for detecting vibration and object deformation using fibre optic Fabry-Perot sensors connected to the registration system.

Synthesis and Study of the Complex Compound of Isonicotinamide with Zinc Nitrate

A complex compound of zinc nitrate with isonicotinamide was synthesized. The advantages of the mechanochemical (solid-phase) method, the optimal conditions of synthesis are presented IR- and 1Н NMRspectroscopic analysis provide information about ligands and the complex compound formed on their basis, the nature of the bond, central atom surrounding, polyhedra, valence and deformation vibrations, shifts in proton signals. Crystallographic data of the complex compound were obtained using a Malvern Panalytical Empyrean diffractometer. Analysis of the obtained results was carried out using FULLPROF and VESTA programs. When the lengths and angles of the valence bonds were analyzed using the MOGUL program adapted to the MERCURY complex, it was found that there were no bonds and angles with non-standard values between them. The state of the central atomic spatial structure, hybridization, binding of the isonicotinamide molecule and the nitric acid residue to the zinc atom were studied. Based on the data obtained, it was concluded.

INFRARED SPECTROSCOPIC ANALYSIS OF COMPLEX COPPER(II) CONTAINING CATALYTIC SYSTEM

The synthesized 2 individual orthophosphate catalysts AlPO4 and Cu3(PO4)2 and 7 new complex aluminum-copper (II) orthophosphate catalytic systems of the type xAlPO4·yCu3(PO4)2 was obtained based on them were investigated by the method of IR spectroscopic analysis. At the same time, the content of both orthophosphates in the catalyst structure varies in the range of 0.5 - 99.5 wt. %. In the entire series of air-dry samples and those baked at the optimal heat treatment temperature (600 °С), the frequencies and intensities of the absorption bands of the IR spectra of the obtained catalytic systems of the type type xAlPO4·yCu3(PO4)2 are characterized by intense absorption in the region of valence vibrations of OH groups of water molecules (3610‒3005 cm-1). Valence vibrations of OH groups of water molecules, which take a direct part in the formation of hydrogen bonds, are observed in the region of 2380‒1880 cm-1. Characteristic manifestations of the hydrogen bond in the vibrational spectrum of H2O, which is part of the structure of the synthesized aluminum-copper (II) orthophosphate catalysts, are a low-frequency shift, an increase in intensity, and a broadening of the bands of valence vibrations of its OH groups. At the same time, in the region 1114‒400 cm-1, valence and deformation vibrations of the orthophosphate ion PO43- are observed, which are clearly expressed in the form of clear absorption bands in the dehydration products for all synthesized binary catalytic systems. Additional coordination of the orthophosphate anion with metal cations Al3+ and Сu2+ is observed. Heating all synthesized orthophosphate samples above 700 °С contributes to their complete dehydration and the emergence of IR spectra characteristic of anhydrous orthophosphate salts.

Extraction of antioxidant and antibacterial agents from avocado (Persea americana) seed using Pulsed Electric Field method

The abundance of avocado seeds causes environmental problems. Therefore, avocado seeds, which are high in bioactive compounds, have been utilized. Several extraction methods have been explored to maximize this utilization. However, conventional extraction methods present major challenges due to disadvantages such as requiring high temperatures, high energy consumption, long extraction times, and producing solvent waste. To that purpose, the Pulse electric field (PEF) extraction method was developed, which is highly efficient, has a short extraction process, is environmentally friendly, and does not produce solvent waste. This study observed the effect of electric field strength (2.5–7.5 kV/cm) and pulse frequency (100–250 Hz) until an optimum point on the properties of avocado seed extract (Avs) as an antioxidant and antibacterial agent. The results show that increasing the electric field strength and pulse frequency boosts the extraction yield and total phenolic content (TPC). This is highly supported by SEM images, which show more pores, cavities, and disrupted membrane cells as the electric field strength and pulse frequency increased. GC-MS and FTIR analysis also showed that the extract contains bioactive compounds such as polyphenols, fatty acids, and other compounds with the representing peaks OH, C−H stretch, CC, −C−H stretch, C−O stretch, and in-plan deformation vibration CH indicating as antioxidant and antibacterial agents. The extract obtained at 7.5 kV/cm with a pulse frequency of 250 Hz shows the best performance of bioactive potential indicated by antioxidant activity, IC50, and surface area of the inhibition zone against E. coli and S. aureus, which are 95.56 %, 90 µg/mL, 396 mm2, and 785 mm2, respectively. The inhibitory zones of the two microbials were relatively stable until the seventh day of observation. This research showed that the EF extraction method serves as an eco-extraction technology of natural bioactive compounds, which has high potential application as an antioxidant and antibacterial agent.

Ammonium salts of sulfur-containing oxyanions resulting from reaction of sulfur dioxide with aqueous solutions of diethylentriamine and bis(hexamethylene)triamine

Interaction in the system "sulfur dioxide–diethylenetriamine (or bis-(hexamethylene)triamine)–water–air oxygen" results in a mixture of double salts (diethylenetriammonium bis(sulfito)-dithionate (Ia) and bis(sulfito)-sulfate trihydrate diethylenetriammonium (Ib)) or bis(hexamethylene)triammonium sulfate (II). The obtained ammonium salts of sulfur-containing oxyanions Ia, Ib, and II were characterized by the methods of elemental analysis, X-ray structural analysis, X-ray powder diffraction, IR spectroscopy, and mass spectrometry. Compound Ia crystallizes in monoclinic syngony (space group С2/с, a=28.1583(5) Å, b=6.84450(10) Å, c=10.8351(2) Å, =93.776(2)0, V=2083.71(6) Å3, Z=4). Compound Ib crystallizes in rhombic syngony (space group Pbcn, a=18.9777(13) Å, b=10.3131(8) Å, c=11.5414(10) Å, V=2258.9(3) Å3, Z=4). Compound II crystallizes in triclinic syngony (space group P-1, a=11.347(3) Å, b=11.700(5) Å, c=18.913(4) Å, =95.22(3)0, =92,52(2)0, =118,27(4)0, V=2191,36 Å3, Z=2). The IR spectrum of the mixture of salts Ia and Ib shows the valence vibrations of (SO) of sulfite anion (1 and 3), represented by bands at 955, 931, 907, 1026, and 1006 cm–1. Two bands at 566 and 493 cm–1 are the result of the splitting of a doubly degenerate out-of-plane deformation vibration of the 4 (E) of dithionate anion. The bands at 1127 and 1078 cm–1 correspond to the oscillations of as and s of sulfate anion (SO42–). A decrease in the symmetry of the SO42– anion as a result of salt formation is accompanied by the appearance of the band 1 (A1) at 980 cm–1 in its spectrum.

3D-printed multifunctional chiral metamaterial with invariant sound absorption under large deformation and low-frequency vibration control

ABSTRACT Acoustic metamaterials provide a distinctive route for reducing low-frequency noise and vibration; however, most are characterised by their singular functionality, e.g. sound absorption or vibration suppression. We present a 3D-printed multifunctional chiral metamaterial (MCM) with double helix structures inspired by cochlea and DNA for excellent acoustic, mechanical, vibration isolation and mitigation properties. By employing impedance matching, nearly perfect sound absorption can be obtained and kept invariably in the low-frequency range under strain from +25% to −25%, as confirmed by the standard impedance tube tests. The double helix structure provides versatile mechanical properties, including compressibility, stretchability, and recoverability. Excellent vibration isolation ability from 94 Hz and strong elastic wave attenuation performance between 199 and 254 Hz based on bandgap strategy are demonstrated by isolation and mitigation vibration tests and simulations. This 3D printed structure presents a promising solution for multipath noise control, setting a paradigm for biologically inspired multifunctional materials.

Blast resistance analysis of butterfly-like reentrant circular honeycomb sandwich structure

Negative Poisson honeycomb has great potential in the field of protection against explosive shock due to its unique tensile expansion characteristics and excellent energy absorption capacity. However, there are limitations in the types and performance enhancement of the current negative Poisson honeycomb sandwich structure (HSS), so to further improve the blast resistance of conventional HSS and reduce the mass of the structures, a butterfly-type reentrant circular HSS is designed in this paper. In this analysis, the JC constitutive model related to the mechanical properties of AL-6XN304 alloy steel was used for simulation, and the explosion load was applied to the sandwich structure using the CONWEP loading mode in ABAQUS, and its explosion process was analyzed numerically in detail. Explosive simulation of square-core HSS is first performed, and the precision of the numerical model is verified by comparing it with the experimental result in the existing literature. Secondly, the dynamic response of the imitation butterfly-type HSS under air loading was investigated, and the blast resistance performance of this structure was compared with that of four HSSs under the same air loading. The effects of explosive mass, cell thickness, cell wall radius, and cell length parameters on the blast resistance of imitation butterfly-type reentrant circular sandwich structure were also explored. Findings indicate that the dynamic response of the butterfly-like reentrant circular HSS is divisible into three distinct phases: core compression, overall deformation, and equilibrium vibration. Compared with the square, circular, reentrant hexagonal, and star HSSs, the center displacement of the front panel of the structure is 22.4, 20.2, 8.8, and 23.0% lower, respectively, and the center displacement of the rear panel is 24.4, 20.6, 7.1, and 8.2% lower, respectively. In addition, the central area of the structure is also the lowest deflection. Therefore, the butterfly-like reentrant circular HSS has the best explosion resistance. The butterfly-like reentrant circular HSS of the front and rear panel deflection and the displacement at the center point escalates as the explosive mass grows, diminishes with the thickening of the cell wall, lessens as the radius of the cell wall shrinks, and lessens as the cell length shortens, the blast resistance of the structure can be further improved.

Superstatistical functions of modified shifted Morse potential for diatomic molecules

The application of the molecular potential model to the study of different thermodynamic systems has been a focus of interest in recent time due to its importance in molecular and chemical physics. Hence, the asymptotic iteration method and the Laguerre polynomials are employed to obtain the eigensolutions of the Schrödinger equation with the modified shifted Morse potential model. Vibrational energy results for different diatomic molecules have been presented numerically, and these results are compared with experimental data and other results from available literature. The variation of normalised wave function and probability density of modified shifted Morse potential for some selected diatomic molecules at the ground- and first-excited states have been considered. Results obtained show that the equally spaced sinusoidal wave curves and varying nodes depend on the level of electron concentrations in the diatomic molecules considered. Partition function and other superstatistical function expressions of modified shifted Morse potential for some diatomic molecules within the modified Dirac delta distribution are obtained, using the Poisson summation formula. The superstatistical plots show a high level of dependence on the temperature parameter, maximum vibrational quantum number and deformation parameter. The superstatistical functions for a deformation parameter of zero correspond to the conventional thermodynamic functions.

Seismic behavior analysis of control rod dropping by vector form Intrinsic Finite-Element method

Control rod drive mechanism (CDRM) play a major role in ensuring safe operation of nuclear reactor during the earthquake, under which the dropping time of control rod is crucial for safe shutdown. Under the earthquake, Rod Cluster Control Assembly (RCCA) has contact collision with the guide tube, resulting in an increase of friction and a decrease of the speed of the falling rod. In addition, in view of the slender structure of the falling rod, the flexible deformation vibration will occur under the impact excitation, which will aggravate the collision and friction. In order to solve the nonlinear problem caused by contact collision between control rod and guide tube, we proposed a dynamic behavior analysis program of rod dropping based on vector finite element method. In order to simulate contact collision force more accurately, we proposed a conformal contact law to simulate the contact force between control rod and guide tube. The vector finite element model and simulation program are validated by comparing with a rod drop experiment. Based on the developed program, the rod dropping behavior, including rod dropping time, contact force, friction force and control rod deformation under several earthquake condition were discussed in this work.

The synthesis, structures and characterizations of (C5H12NO)4Cd3Cl10·2H2O and (C5H12NO)2BiCl6·H5O2 crystals

Two new organic-inorganic hybrid crystals (C5H12NO)4Cd3Cl10·2H2O and (C5H12NO)2BiCl6·H5O2 were synthesized by solution method, and their basic physical properties, including structures, thermal stability analysis, UV–Vis diffuse reflectance absorption spectra and photoluminescent characteristic were characterized. The two crystals both crystallize in same monoclinic crystal system, but different P21/c and C2/c space group for (C5H12NO)4Cd3Cl10·2H2O and (C5H12NO)2BiCl6·H5O2, respectively. Their infrared, Raman and mass spectrometry were measured, with related characteristic peaks were identified. The Raman peaks at 249 and 88 cm−1 are ascribed to Cd-Cl stretching vibration and Cl-Cd-Cl deformation vibration, respectively. The mass spectra analysis confirm the existence of C5H12NO+ cation, [CdCl]+ and Na-(C5H12NO)2BiCl6·H4O2. A phase transition peak that respectively located at 378 and 403 K for (C5H12NO)4Cd3Cl10·2H2O and (C5H12NO)2BiCl6·H5O2 was detected by the synchronous thermal analysis, which is related with the loss of crystalline water in their structures. In addition, the maximum absorption peak at 230 and 240 nm, with corresponding band gap of 3.35 and 3.15 eV were fitted for (C5H12NO)4Cd3Cl10·2H2O and (C5H12NO)2BiCl6·H5O2, respectively. Furthermore, (C5H12NO)4Cd3Cl10·2H2O features a bluish white emission with the peak centering at 496 nm when it was excited at 380 nm by a Xenon lamp. This work extends the catalog of organic-inorganic hybrid metal halides and presents the potential application of (C5H12NO)4Cd3Cl10·2H2O in optical field.

“Chacco” clay from the Peruvian highlands as a potential adsorbent of heavy metals in water

This research aimed to remove Cd (II), Cr (VI), Ni (II), Pb (II), and V (V) from aqueous solutions prepared in distilled water using “Chacco” clay from the Peruvian highlands as adsorbent. The adsorption process was carried out in Batch type systems for 120 min using solutions of each metal at a concentration of 5 mg/L in aqueous systems of a single metal or monometallic (MAS) and solutions of the five metals simultaneously or multimetallic (MMAS). For this purpose, the “Chacco” clay was first characterized by SEM-EDS analysis, finding a laminated clay structure with an elemental composition of C, Al, Fe, Na, Mg, Ca, K, As, Cu, Pd, O, and Ta. The results using 10 g/L of “Chacco” clay showed that the best adsorption efficiency in both MAS and MMAS aqueous systems is achieved at pH = 4 achieving in MAS aqueous systems the removal of 64.16 ± 0.98 % of Cd (II), 95.70 ± 0.81 % of Cr (VI), 97.20 ± 0.89 % of Ni (II), 92. 78 ± 0.79 % of Pb (II), and 95.80 ± 0.67 % of V (V), on the other hand, in aqueous MMAS systems a decrease in adsorption efficiency was observed, managing to remove 6.88 ± 0.53 % of Cd (II), 63.04 ± 0.94 of Cr (VI), 7.81 ± 0.43 % of Ni (II), 62.34 ± 0.77 % Pb (II), and 14.33 ± 0.56 % of V (V). The kinetic study showed that the adsorption mechanism would correspond to chemisorption since the process fitted best to the pseudo-second order model and Elovich. SEM-EDS analysis after adsorption confirmed the presence of the heavy metals under study in the “Chacco” clay. Metal adsorption is evidenced at 1418 cm−1 by -CH2-metal deformation vibrations according to FTIR analysis. In conclusion, the “Chacco” clay would be a promising adsorbent of heavy metals in polluted waters so that scaling up to real environments could be feasible. On the other hand, the “Chacco” clay is consumed by the population of Puno, Peru, therefore its potential impact on health should be evaluated due to its capacity to accumulate metals and the presence of Al in this clay.

Transesterification of Azadirachta indica seed oil into biodiesel using MgO-supported tri-metallic catalyst– synthesis and characteristic evaluation

Environmentally sustainable biodiesel from non-edible waste Azadirachta indica (neem) seed oil provides an economical alternative to combat issues caused by fossil fuel combustion. The current study reports specifically a bi-functional trimetallic (Ca-Sr-Mo) catalyst delineated across MgO support synthesized via wet impregnation and green synthesis route using Cassia fistula extract. In FTIR analysis, peaks appeared at 992, 1390, 1424 cm−1 represent the C–O stretching, C–H deforming and M–O–M bending deformation vibrations, respectively. The diffraction peaks of all CaO, SrO, MoO2, and MgO in the XRD pattern represent the formation of catalysts. The prepared catalyst is employed in the transesterification reaction to convert A. indica oil into fatty acid methyl ester. The study used the response surface methodology to examine factors that could affect the conversion rate, including oil-methanol molar ratio, reaction time, and catalyst loading. The results were analyzed to determine the best combination of factors that yields the optimal catalytic transesterification process. The highest yield of 89.92 % was achieved under optimum conditions of methanol-to-oil (18:1), catalyst loading (5 wt%), and time (6 h). In FTIR analysis, the new peak appeared at 1160 cm−1, indicating the formation of methyl esters, while 1H NMR analysis confirmed the successful conversion of A.indica oil into FAMEs by the appearance of strong singlet at 3.66 ppm for methoxy proton.1H NMR also indicated a high yield (90.09 %) which is comparable to RSM obtained yield. Additionally, a reaction mechanism has been proposed. Specifically, GC-MS FAME profiles and physicochemical testing confirmed that biodiesel meets ASTMD6751 and EN14214 standards with key fatty acid methyl esters and desirable properties.

Rapid monitoring of structural deformation based on unsupervised segmentation model

This paper presents a novel approach for rapid structural deformation monitoring using an enhanced segmentation model, SAM-DM (Segment Anything Model-Deformation Monitoring). The method enhances the SAM model by integrating an innovative point prompt generation technique, image fusion, and connected domain analysis, enabling structural deformation monitoring with just a single manual click on the target area in the initial video frame. Specifically, this manual click generates coordinate information for the target area, serving as a point prompt for the SAM-DM model. This process results in the creation of a high-quality binary mask, which is then fused with the original image to isolate only the target area. Subsequently, connected domain analysis is employed to automatically process the mask, extracting the pixel centroid coordinates of the target area, which are then used as prompts for segmenting subsequent frames. This approach allows continuous tracking of changes in the target area's coordinates, thereby facilitating rapid structural deformation monitoring. Experimental results demonstrate that this method can accurately monitor deformation across all target points and adapt to varying lighting conditions and noise levels. Applied to monitor the bending deformation of reinforced concrete beams and the in-plane deformation of concrete slabs, the method achieves results closely aligned with actual measurements, yielding relative errors of 0.95 % and 0.48 %, respectively. Additionally, in monitoring the vibrational deformation of steel frames, the primary frequency of the curve precisely matches measured values, confirming that the SAM-DM-based method delivers both high accuracy and strong robustness.

Numerical investigation of cavity dynamics and cavitation-induced vibrations of a flexible hydrofoil

This work investigates the cavitation and fluid–structure interaction characteristics of a flexible NACA0015 hydrofoil. The simulation incorporates the Zwart–Gerber–Belamri cavitation model and two-way fluid–structure interactions. The detached eddy simulation method is employed to analyze the impact of cavitation and elastic deformation on hydrodynamic performance. The vibrational response and cavitating flow field around the hydrofoil are investigated. The results show that the vibrational mode of the elastic hydrofoil shifts with increasing flow speed. Furthermore, the vertical vibrational displacement of the hydrofoil aligns with the variations in cavitation volume in the flow field. The structural vibrational deformation of an elastic hydrofoil notably affects the evolution of cavitation. Additionally, fluid–structure interaction in the presence of cavitation influences the pattern of vortex shedding wakes in the flow field. The results of this study can serve as a reference for the design of hydrofoils constructed from composite elastic materials.

Dynamic analysis and shape sensing of pipes subjected to water hammer by the inverse finite element method

Pipe structures are commonly employed in modern industries. However, the transient pressure induced by water hammer leads to a high risk of structural damage, highlighting the importance of Structural Health Monitoring (SHM). The inverse Finite Element Method (iFEM) offers a way to reverse structural deformations based on a set of discrete strain data. In this paper, the water hammer phenomenon in a Reservoir-Pipe-Valve (RPV) system is investigated. The element iQS4 is adopted to reconstruct dynamic deformations for the pipe using iFEM. The water hammer resulting from an instantaneous closure of the valve can generate significant fluid pressure, leading to severe pipe vibrations. The vibration deformations can be monitored by iFEM. The maximum error of the pipe nodal displacement is below 3 % and the average error is below 2 % in the proposed several sensor location cases, even the mesh of iFEM is coarser than the FE model. Among the sparse sensor location cases, the X path which is suitable for Fiber Bragg Grating (FBG) sensors has the highest accuracy of the displacement reconstruction. The results reveal a promising prospect in the real-time monitoring based on iFEM for pipes.

Ocean wave energy harvesting: Utilizing buoy float to induce dielectric elastomer deformation and electret vibration for power generation

The dielectric elastomeric polymer material, characterized by its high energy output, resilience, mechanical compliance, lightweight, damage tolerance, and low cost, demonstrates significant potential as an innovative sustainable energy converter. It seamlessly adapts to the ever-changing climatic conditions of the ocean, converting the violent impacts of wave kinetics into electrical energy. This paper proposed a viable electret and dielectric elastomer wave energy harvester to convert ocean wave energy into electricity and aims to achieve self-priming operation in the conjugate components. The output voltage from the electret also functions as the bias voltage for the dielectric elastomer, based on the intrinsic variable capacitance electric translation principle. The dielectric elastomer's deformation, equivalent to variable capacitance, successfully converted the mechanical energy from the ocean waves into electrical energy. The ocean wave energy conversion is evaluated using a system-level approach, incorporating theoretical, simulation, and experimental models. In addition, electric power generation is assessed with parameters such as output voltage, electret surface potential, and bias voltage. Essentially, the electric energy produced by the electret generator can serve as the bias voltage source for the dielectric elastomer generator, providing a self-sustaining solution for ocean wave energy harvesting. The innovative power device envisions various potential configurations for ocean-based power generation.

Innovative Structural Optimization and Dynamic Performance Enhancement of High-Precision Five-Axis Machine Tools

To satisfy the requirements of five-axis processing quality, this article improves and optimizes the machine tool structure design to produce improved dynamic characteristics. This study focuses on the investigation of five-axis machine tools’ static and dynamic stiffness as well as structural integrity. We also include performance optimization and experimental verification. We use the finite element approach as a structural analysis tool to evaluate and compare the individual parts of the machine created in this study, primarily the saddle, slide table, column, spindle head, and worktable. We discuss the precision of the machine tool model and relative space distortion at each location. To meet the requirements of the actual machine, we optimize the structure of the five-axis machine tool based on the parameters and boundary conditions of each component. The machine’s weight was 15% less than in the original design model, the material it was subjected to was not strained, and the area of the structure where the force was considerably deformed was strengthened. We evaluate the AM machine’s impact resistance to compare the vibrational deformation observed in real time with the analytical findings. During modal analysis, all the order of frequencies were determined to be 97.5, 110.4, 115.6, and 129.6 Hz. The modal test yielded the following orders of frequencies: 104, 118, 125, and 133 Hz. Based on the analytical results, the top three order error percentages are +6.6%, +6.8%, +8.1%, and +2.6%. In ME’scope, the findings of the modal test were compared with the modal assurance criteria (MAC) analysis. According to the static stiffness analysis’s findings, the main shaft and screw have quite substantial major deformations, with a maximum deformation of 33.2 µm. Force flow explore provides the relative deformation amount of 26.98 µm from the rotating base (C) to the tool base, when a force of 1000 N is applied in the X-axis direction, which is more than other relative deformation amounts. We also performed cutting transient analysis, cutting spectrum analysis, steady-state thermal analysis, and analysis of different locations of the machine tool. All of these improvements may effectively increase the stiffness of the machine structure as well improve the machine’s dynamic characteristics and increases its machining accuracy. The topology optimization method checks how the saddle affects the machine’s stability and accuracy. This research will boost smart manufacturing in the machine tool sector, leading to notable advantages and technical innovations.