Asymmetric Vibration Research Articles

An Innovative Use of Hydroxyapatite (HAp) from Pokea Clam Shells (Batissa violacea var. celebensis) for Toothpaste Manufacturing

Innovation research on the use of hydroxyapatite from pokea clam shells (Batissa violacea var. celebensis) for toothpaste manufacturing has been successfully conducted. This study aims to determine how to synthesize and characterize hydroxyapatite (HAp) from pokea shells and the efficiency of its use in making toothpaste. The research process was conducted through hydroxyapatite synthesis and hydroxyapatite toothpaste formulation. The success of this synthesis was proven by the characterization of XRF spectrophotometer, FTIR spectrophotometer and digital optical microscope. The results of XRF analysis showed that the CaO content in the material was 88.21%. The results of FTIR analysis showed that in hydroxyapatite material there was absorption at wave numbers 926 cm-1 and 1024 cm-1 which showed asymmetric strain vibrations and bending vibrations of PO43- groups. The results of XRD characterization of HAp show that the diffraction peak is at an angle of 2θ = 20-57 ° with a crystal size of 46.15 nm and a degree of crystallinity of 85.43%. Digital optical microscope test results at 500x and 1000x magnification, showed hydroxyapatite has a uniform and non-porous shape. The hydroxyapatite toothpaste produced is bone white in color with menthol aroma and slightly rough texture. The resulting toothpaste is homogeneous, the diameter of the distribution that meets the quality requirements of toothpaste is 6.833 cm. The pH measurement result on toothpaste is 5.82 which meets the toothpaste quality requirements. The result of viscosity measurement on toothpaste is 20,000 cpa.s which meets the requirements of toothpaste viscosity. The foam formed is 10 mm where the height of the foam formed has met the requirements. Hydroxyapatite toothpaste has good stability and strong antibacterial activity, where the clear zone formed is 18.7 mm

Research on a novel non-uniform and asymmetric ultrasonic vibration system

Abstract A new type of non-uniform and asymmetric ultrasonic vibration system (UVS) is proposed and applied to the turning process. The research results show that the design theory of the non-uniform and non-symmetric UVS is accurate and reliable. The theoretical design frequency and modal simulation frequency error of ultrasonic vibration turning system is only 2.5%. The designed non-uniform and non-symmetric UVS has excellent vibration performance and stability, and the established simulation model can predict surface microtexture accurately. The vibration mode output by the non-uniform and non-symmetric UVS is longitudinal-bending vibration, and the actual vibration performance is excellent. Compared with conventional cutting, the addition of longitudinal-bending ultrasonic vibration under the same conditions can give the machined surface a microscopic textured structure, reduce surface roughness and water contact angle, and improve surface wettability. The minimum surface roughness obtained in the experiment is 1.005 μm. The orthogonal experiment results show that there is a correlation between the machining parameters, surface micro-structure parameters, surface wettability, and surface roughness.

Thermoelastic damping in asymmetric vibrations of nonlocal circular plate resonators with Moore-Gibson-Thompson heat conduction

Precise estimation of the amount of thermoelastic damping (TED) in small-sized resonators is one of the crucial issues in their optimal design. According to several experimental, numerical and theoretical findings, the behavior of structures with such small dimensions in structural and thermal domains does not follow classical elasticity theory and the Fourier law of heat conduction. The objective of this work is to develop a nonclassical formulation for computing TED in asymmetric vibrations of circular nanoplates according to nonlocal theory (NT) and Moore-Gibson-Thompson (MGT) heat transfer model. To do so, first, the coupled equations of motion and heat are derived in the purview of NT and MGT model. Then, the real and imaginary parts of the system frequency are extracted from the frequency equation affected by thermoelastic coupling. Finally, by means of the existing definition for TED, a mathematical expression including nonlocal parameter of NT and nonclassical constants of MGT model is obtained to make an estimate of TED value. In the numerical examples section, to ensure the credibility of the provided formulation, the results obtained through this model are compared with those reported in the literature in the context of simpler models. Then, by presenting various graphical data, the type and extent of the role of different factors in TED changes are appraised. The obtained results indicate that employing NT and MGT model can substantially impact the amount of TED compared to the estimations of the classical formulation. Furthermore, the comparison of results reveals that the magnitude of TED in asymmetric vibration modes surpasses that in symmetric ones, and consequently incorporating asymmetric vibration modes is crucial for thorough analysis of TED in circular nanoplates. Thus, the formulation presented in this article can aid in achieving an optimal design for such plates, particularly in terms of minimizing energy loss.

Structural, optical and magnetic characteristics of Mg2+- doped (Ba0.94Sr0.06)(Fe0.80Al0.20-xMgx)O3-ẟ (x = 0–0.20) oxides

Perovskite-type ABO3 oxides have attracted immense attention in recent technologies e.g., gas sensors, solar cells, fuel cells, oxygen-permeable membranes, etc. An attempt has been made here to synthesize (Ba0.94Sr0.06)(Fe0.80Al0.20-xMgx)O3-ẟ (x = 0–0.20) oxides using sol-gel method and characterized with regards to phase, Raman and magnetic properties. X-ray diffraction-cum-Rietveld refinement shows the structural transformation from cubic (Pm3m) to hexagonal (P63/mmc) via cubic (Pm3m) + rhombohedral (R3c) and increase of cubic lattice parameter ac = 4.0369–4.1296 Å with magnesium. FT-IR spectra exhibit different vibrational bands at 548, 555, 638, 667, and 692 cm−1, representing the metal-oxygen (M-O-M) bond vibrations (M - Fe, Mg, Al), deformation of MO6 octahedral, and internal changes in bond lengths. No Raman band was appeared for cubic phase with x=0–0.10. Bands between ∼ 250–450 cm−1 assign the tilting, rotation, and asymmetric bending vibrations of Fe – O, Mg – O and Al – O bonds and asymmetric bending mode of (Fe/Mg/Al)O6 octahedra. Oxygen bending vibration, anti-stretching mode and presence of oxygen vacancies lie in the bands of range ∼498–656 cm−1. Maximum coercivity (Hc ∼ 1081 Oe) and remanent magnetization (Mr ∼ 0.033 emu/g) have been observed for x = 0 and found similar variation with ‘x’. The saturation magnetization (Ms) and anisotropic constant (K1) values lie as Ms = ∼ 0.678 – 0.754 emu/g and K1 = ∼ 1.38× 104 – 1.53× 104 erg/cm3, respectively with magnesium (x). Presence of anion vacancies and high coercivity make the materials suitable for industrial applications.

An alternative approach in the synthesis of strontium-hydroxyapatite and strontium hydroxyapatite embedded in graphitic carbon nitride nanocomposites for potential tissue engineering applications

Sr-hydroxyapatite has drawn much attention with promising applications in biomedical engineering especially in drug delivery and tissue repair. A novel protocol for the preparation of Strontium hydroxyapatite (Sr-HAP) and Strontium hydroxyapatite encapsulated by graphitic carbon nitride (Sr-HAP@gCN) with high purity and better homogeneity was adopted for potential use in orthopaedic surgeries. The physiological pathway of Strontium and calcium inside humans follow the same trend leading to the mineral deposition of the bone. In the present study, a novel attempt in synthesizing Sr-HAP and Sr-HAP@gCN by the hydrothermal method is proposed for obtaining an ideal biomaterial with potential biocompatibility and pharmacological activity. Phase identification by X-ray diffraction (XRD), Fourier transform Infra-Red spectroscopic analysis (FTIR), Electron & atomic force microscopic studies, Thermogravimetric and Raman spectroscopic analysis was performed on the prepared Sr-HAP and Sr-HAP@gCN to characterize the incorporation efficiency of Strontium. Resazurin microtiter assay and MTT assay were used to evaluate antimicrobial susceptibility and biocompatibility. The typical crystal phase of Sr-HAP and a phase change in Sr-HAP@gCN have been demonstrated with special reference to the interfacial connection between gCN and Sr-HAP through FT-IR studies. Raman spectroscopy revealed the archetypal signature of symmetric and asymmetric PO vibrations pertaining to linearity change with the addition of Strontium. The biological effect of Sr-HAP and Sr-HAP@gCN was quite significant in inducing mineralization when kept immersed in simulated body fluid (SBF) for 21 days. Promising results pertaining to antimicrobial susceptibility and biocompatibility have been proved as an encouraging choice for drug delivery applications and bone filling applications.

Pressure Distributions in Glottal Geometries With Multichannel Airflows

Computer simulation of self-sustained oscillation of the vocal folds has been successful with application of simple Bernoulli-like driving pressures. As voice simulation is now applied to asymmetric vibration with complex mode structures that yield partial vocal fold contact, the driving pressures need refinement. Two independent approaches were used to obtain pressure distributions. The first was a high-fidelity immersed-boundary method computation and the second was a series of pressure tap measurements on scaled-up physical models. Glottal geometries were based on normal surface modes of vibration. Samples are chosen from a large inventory of measured and calculated profiles. Pressure distributions show the complexity that can exist in the driving forces on vocal fold surfaces. Qualitative similarity between computation and measurement was established for a variety of contact patterns, showing diverse pressure gradients in multiple directions. Simplified Bernoulli approaches to glottal pressure distributions are defensible when a single flow channel is preserved in vocal fold oscillation. However, when there are contact islands that produce confluence or difluence of multiple airflow channels, the pressure gradients vary profoundly. Small quantitative differences were observed between measurement and calculation, primarily due to spatial sampling.

A Positioning and Recognition Method Based on Bilinear Time–Frequency Transform and CNN for Long-Range Asymmetric Interferometer Vibration Sensor

A Positioning and Recognition Method Based on Bilinear Time–Frequency Transform and CNN for Long-Range Asymmetric Interferometer Vibration Sensor

Symmetric and asymmetric vibration and buckling of a thermal rotating annular-plate with Pasternak foundation

This paper studies the symmetric and asymmetric vibration and buckling modes of a rotating thermal annular plate resting on a Pasternak foundation. With considering the von Kármán geometric nonlinearity and the first-order shear deformation theory, the governing equations of the system are established via Hamilton's principle, and then solved by using the differential quadrature method. With both inner and outer boundaries constrained, the modes of the rotating system vary differently depending on the mode symmetry. The symmetric modes are mainly affected by the generated centrifugal force, while the asymmetric ones are affected by both centrifugal and Coriolis forces. The additional Coriolis, with mainly two directions, strengthens the forward travelling parts of the asymmetric modes, but makes the backward counterparts buckled more easily. Also, the thermal effect, as well as boundary elasticity and foundation coefficients, are also investigated from the viewpoint of mode symmetry. Results show that the temperature rise can shift the fundamental vibration mode from the symmetric one to the asymmetric one and backward travelling waves for rotation, which also adds to the complexity of mode variation with joint parameters. For the joint effect of the temperature rise and rotating, the annular plate tends to buckle more readily while the effects of the two factors are linearly superimposed.

Asymmetric triangular body-cover model of the vocal folds with bilateral intrinsic muscle activation.

Many voice disorders are linked to imbalanced muscle activity and known to exhibit asymmetric vocal fold vibration. However, the relation between imbalanced muscle activation and asymmetric vocal fold vibration is not well understood. This study introduces an asymmetric triangular body-cover model of the vocal folds, controlled by the activation of bilateral intrinsic laryngeal muscles, to investigate the effects of muscle imbalance on vocal fold oscillation. Various scenarios were considered, encompassing imbalance in individual muscles and muscle pairs, as well as accounting for asymmetry in lumped element parameters. Measurements of amplitude and phase asymmetries were employed to match the oscillatory behavior of two pathological cases: unilateral paralysis and muscle tension dysphonia. The resulting simulations exhibit muscle imbalance consistent with expectations in the composition of these voice disorders, yielding asymmetries exceeding 30% for paralysis and below 5% for dysphonia. This underscores the relevance of muscle imbalance in representing phonatory scenarios and its potential for characterizing asymmetry in vocal fold vibration.

Характеристики эласмоидной чешуи рыб и ее фракций, по данным ИК-Фурье-спектроскопии

Elasmoid scales of pike-perch (Sander lucioperca), white amur (Ctenopharyngodon idella), carp (Cyprinus carpio), freshwater bream (Abramis brama) and crucian carp (Carassius carassius) were processed without hydrolysis by “dry” method in order to study the characteristics of the obtained finished product, which determine its further use as additives for food and other purposes. The essence of the method consisted in washing the scales, its subsequent drying, grinding and separation, with obtaining two fractions enriched with both organic (cotton-like product) and inorganic (powder) components. FT-IR spectroscopy was used to characterize the scale samples and their enriched fractions. Characteristic bands known for collagen, in particular for Amide I, Amide II, Amide III, Amide A, were observed in the IR spectra of all the samples studied. The bands (inorganic part) at ~1022 cm–1 and at ~599 cm–1 indicate valence asymmetric vibrations of PO43– groups. Numerous bands for all experimental samples in the wavelength region 3900-3500 cm–1 can be caused by vibrations of OH groups, which is associated with the presence of water in the tested samples. Comparison of the absorption intensity in the region of characteristic frequencies of collagen and hydroxyapatite calculated by the IR method can be one of the approaches for the development of a rapid method for the determination of their quantitative content in fractions obtained from fish scales. Organic and mineral additives from fish scales can be recommended as components of formulations of various food products, as well as raw materials in tissue engineering, orthopedics and dentistry.

A novel asymmetric tri-stable piezoelectric vibration energy harvester for low-orbit vibration energy harvesting enhancement

This study introduces an innovative asymmetric tri-stable piezoelectric vibration energy harvester (ATPVEH) augmented with an elastic base (EB), aimed at optimizing energy capture from low-orbit vibrations. This design incorporates a uniquely configured asymmetric tri-stable piezoelectric cantilever beam, positioned within a U-shaped block that is further enhanced by an elastic base. A strategically placed spring (kf)–mass (Mf) system, situated between the U-shaped block and the constrained end of the beam, significantly boosts the vertical displacement of the beam during vibrational events. We developed a dynamic model for the ATPVEH+EB utilizing Lagrange’s equations, exploring the impact of various factors—including the asymmetry of the potential well, the stiffness of the elastic base, the mass of the spring–mass system, and the load resistance—on the system’s nonlinear dynamic responses. Our findings indicate that the ATPVEH+EB facilitates more efficient energy harvesting from low-orbit vibrations, demonstrating dual response peaks across its operational frequency spectrum. Notably, the displacement and output voltage amplitudes of the ATPVEH+EB can be enhanced by increasing mf or decreasing kb, whereas the peak output power transitions toward a lower frequency range as the load resistance escalates. Both theoretical analyses and numerical simulations corroborate the ATPVEH+EB’s superior performance in harvesting energy within low-orbit vibrational environments.

Asymmetric vibrations in the organ of Corti by outer hair cells measured from excised gerbil cochlea

Pending questions regarding cochlear amplification and tuning are hinged upon the organ of Corti (OoC) active mechanics: how outer hair cells modulate OoC vibrations. Our knowledge regarding OoC mechanics has advanced over the past decade thanks to the application of tomographic vibrometry. However, recent data from live cochlea experiments often led to diverging interpretations due to complicated interaction between passive and active responses, lack of image resolution in vibrometry, and ambiguous measurement angles. We present motion measurements and analyses of the OoC sub-components at the close-to-true cross-section, measured from acutely excised gerbil cochleae. Specifically, we focused on the vibrating patterns of the reticular lamina, the outer pillar cell, and the basilar membrane because they form a structural frame encasing active outer hair cells. For passive transmission, the OoC frame serves as a rigid truss. In contrast, motile outer hair cells exploit their frame structures to deflect the upper compartment of the OoC while minimally disturbing its bottom side (basilar membrane). Such asymmetric OoC vibrations due to outer hair cell motility explain how recent observations deviate from the classical cochlear amplification theory.

FT-Raman and FTIR spectroscopy as a tools showing marker of platinum-resistant phenomena in women suffering from ovarian cancer

Platinum-resistant phenomena in ovarian cancer is very dangerous for women suffering from this disease, because reduces the chances of complete recovery. Unfortunately, until now there are no methods to verify whether a woman with ovarian cancer is platinum-resistant. Importantly, histopathology images also were not shown differences in the ovarian cancer between platinum-resistant and platinum-sensitive tissues. Therefore, in this study, Fourier Transform InfraRed (FTIR) and FT-Raman spectroscopy techniques were used to find chemical differences between platinum-resistant and platinum-sensitive ovarian cancer tissues. Furthermore, Principal Component Analysis (PCA) and machine learning methods were performed to show if it possible to differentiate these two kind of tissues as well as to propose spectroscopy marker of platinum-resistant. Indeed, obtained results showed, that in platinum-resistant ovarian cancer tissues higher amount of phospholipids, proteins and lipids were visible, however when the ratio between intensities of peaks at 1637 cm−1 (FTIR) and at 2944 cm−1 (Raman) and every peaks in spectra was calculated, difference between groups of samples were not noticed. Moreover, structural changes visible as a shift of peaks were noticed for C–O–C, C–H bending and amide II bonds. PCA clearly showed, that PC1 can be used to differentiate platinum-resistant and platinum-sensitive ovarian cancer tissues, while two-trace two-dimensional correlation spectra (2T2D-COS) showed, that only in amide II, amide I and asymmetric CH lipids vibrations correlation between two analyzed types of tissues were noticed. Finally, machine learning algorithms showed, that values of accuracy, sensitivity and specificity were near to 100% for FTIR and around 95% for FT-Raman spectroscopy. Using decision tree peaks at 1777 cm−1, 2974 cm−1 (FTIR) and 1714 cm−1, 2817 cm−1 (FT-Raman) were proposed as spectroscopy marker of platinum-resistant.

Preparation and Study of Structural, Optical and Electrical Properties of the Composite Films [PVA-PEO-MnCl2.4H2O

In the present paper, pure polymeric blend film [PVA-PEO] and the polymeric blend films reinforced by MnCl2.4H2O salt with different weight ratios (10, 20, 30, 40, 50 wt %) have been prepared by using the solution casting method. The effects of weight ratio of salt on structural properties for all reinforced polymeric blends films were studied. FTIR spectra were used to establish the interaction between the polymer (PVA) and the polymer (PEO) reinforced by MnCl2.4H2O salt, which causes some changes in the vibration modes and the position of the bonds. All inrestigated samples exhibited broad bonds at around (3310 cm-1). The results showed the asymmetric vibration of O-H group in the polymers matrix. The peaks around (2880 cm-1) can be attributed to the presence of C- H stretching vibration group. The C=C stretching vibration appears in the bonds at (1955 cm-1). The peak at (1096 cm-1) for all reinforced films is attributed to the stretching mode of C-O-C stretching. There is a shift of out-of-plane rings C-H bending vibration from 961.2 to 955 cm-1. These indicate the chemical interactions of MnCl2.4H2O salt with the polymeric blend [PVA-PEO]. The two strong bonds observed around (1471 cm-1 and 844 cm-1) are assigned to the bending and stretching vibration of the CH2 group, respectively. The change in the spectral intensities of polymeric blend [PVA-PEO] involves a shift in some bonds due to the MnCl2.4H2O salt addition. The effects of weight ratio of salt on optical properties for all reinforced polymeric blends films were studied, as the transmittance and absorbance spectra were recorded within the range of wavelengths (190-1100) nm, and it was found that the energy gap value decreases with an increase of the added salt’s weight ratio. Results showed that the indirect electronic transitions are allowed. Effects of salt’s weight ratio on electrical (dielectrical) properties for all reinforced polymeric blends films were studied, and the practical results showed a decrease in the dielectric constant (ε΄) with an increase in frequency for all polymeric blends films, while the practical results also showed an increase in the alternating electrical conductivity (σa.c) with increasing frequency for all polymeric blends films, as well as an increase in both the dielectric constant and alternating electrical conductivity with an increase in the added salt’s weight ratio at same frequency.

Experimental research on the influence of acid on the chemical and pore structure evolution characteristics of Wenjiaba tectonic coal.

The chemical and pore structures of coal play a crucial role in determining the content of free gas in coal reservoirs. This study focuses on investigating the impact of acidification transformation on the micro-physical and chemical structure characteristics of coal samples collected from Wenjiaba No. 1 Mine in Guizhou. The research involves a semi-quantitative analysis of the chemical structure parameters and crystal structure of coal samples before and after acidification using Fourier Transform infrared spectroscopy (FTIR) and X-ray diffraction (XRD) experiments. Additionally, the evolution characteristics of the pore structure are characterized through high-pressure mercury injection (HP-MIP), low-temperature nitrogen adsorption (LT-N2A), and scanning electron microscopy (SEM). The experimental findings reveal that the acid solution modifies the structural features of coal samples, weakening certain vibrational structures and altering the chemical composition. Specifically, the asymmetric vibration structure of aliphatic CH2, the asymmetric vibration of aliphatic CH3, and the symmetric vibration of CH2 are affected. This leads to a decrease in the contents of -OH and -NH functional groups while increasing aromatic structures. The crystal structure of coal samples primarily dissolves transversely after acidification, affecting intergranular spacing and average height. Acid treatment corrodes mineral particles within coal sample cracks, augmenting porosity, average pore diameter, and the ratio of macro-pores to transitional pores. Moreover, acidification increases fracture width and texture, enhancing the connectivity of the fracture structure in coal samples. These findings provide theoretical insights for optimizing coalbed methane (CBM) extraction and gas control strategies.

Raman spectroscopy of kassite, lucasite-(Ce), La analogue of lucasite, and cafetite

Raman spectra of lucasite-(Ce), La-analogue of lucasite, kassite and cafetite are significantly different. Most evident differences were revealed in the position of bands corresponding to vibrational modes for bands assigned to symmetrical v1(Ti-O) and asymmetrical v3(O-Ti-O) stretching vibrations, as well as the bands determined by asymmetrical bending vibrations v4(transTiO6) and asymmetrical v3(O-Ti-O) stretching vibrations. Raman spectra of lucasite-(Ce) and La-analogue of lucasite are published for the first time. The presented data are valuable for the identification of cafetite and kassite group minerals using Raman spectroscopy.

Chemically Synthesized Sb-Doped SnO2 Nanoparticles for Supercapacitor Application

This study explores the potential of antimony tin oxide (ATO) as an electrode material for supercapacitor applications. ATO, known for its exceptional electrical conductivity and stability, was synthesized using the coprecipitation method followed by calcination. The resulting ATO powder underwent thorough characterization through X-ray diffraction (XRD), scanning electron microscopy (SEM), and Fourier-transform infrared spectroscopy (FTIR). XRD analysis confirmed the tetragonal morphology and phase purity of ATO nanoparticles, while SEM revealed a sphere-like structure with an irregular surface. FTIR spectroscopy identified various functional groups, including O–H stretching, C–H symmetric and asymmetric vibrations, and the characteristic–SnO2; vibration mode, providing insights into the surface properties crucial for electrochemical performance. Electrochemical evaluations, conducted through cyclic voltammetry, galvanostatic charge-discharge, and electrochemical impedance spectroscopy, demonstrated a specific capacitance of 140 F/g for the ATO electrode. This notable specific capacitance highlights the potential of ATO as an advanced electrode material for supercapacitors, showcasing its suitability for applications requiring rapid charge-discharge cycles and high specific power. This research contributes to the understanding of ATO’s structural and functional aspects, emphasizing its promising role in advancing supercapacitor technology. The synthesized ATO nanoparticles, characterized by their unique morphology and enhanced electrochemical performance, pave the way for cleaner and more efficient energy storage solutions.

Enhancing the Biosorption Potential of Pichia kluyveri FM012 for 4-Bromophenols

AbstractThe use of toxic and persistent pesticides in agriculture results in serious and lasting environmental impacts. Although traditional methods, such as physical and chemical reclamation, yield the best results, treating these contaminants requires a high cost and expertise. Therefore, this study focuses on bioremediation recovery, which is more efficient, economical, and safer for removal. In this case, the newly isolated potential of Pichia kluyveri FM012 in degrading 4-bromophenol was investigated. The impact of optimized parameters such as agitation, pH, nitrogen, and carbon source were also studied. After extensive testing, the best optimal degradation occurred at pH 5 with a stirrer speed of 150 rpm. Glucose and yeast performed the best compared to other carbon and nitrogen sources. The Langmuir model predicted the maximum biosorption capacity (qm = 38.46 mg/g biomass), but the Freundlich model provided a better value of R2 = 0.999. The pseudo-second-order kinetic model was fitting for the study of biosorption kinetics. The FTIR spectrum revealed the presence of asymmetric and symmetric vibrations of the aromatic ring and was assigned to C = C or C = O. Fungi showed biosorption ability across broad functional groups. These results provide interesting information about the ability of Pichia kluyveri FM012 and its potential applications for remediating resistant pesticides.

Characterization and antimicrobial Properties of Cotton Fabric Loaded with green Synthesized Silica Nanoparticles

During the past decade, improvement in the functionality of textile materials has become an important research field due to their significant health and safety benefits. Here we report, simple and cost-effective green synthesis of silica nanoparticles from fibrous residue of sugarcane bagasse followed by investigating the applicability on cotton fabric. The characteristics of synthesized nanoparticles were determined by techniques including FTIR (exhibited characteristic peak at 791.01 attributed to vibration of Si-O and the absorption band at 1072.48 cm-1 owing to asymmetric vibration of Si-O-Si confirming the formation of SNPs), SEM (40±2nm), and XRD (Examined spectra with JCPDS 36-1451 indicate well-defined peaks of Silicon Oxide). Debye Scherrer equation was used to calculate the mean crystallite size (19.79 nm) of powder Silica NP sample at the full width half maximum (FWHM) of the diffraction peaks of 2Ɵ positions. Applicability of synthesized nanoparticles was determined by assessing thermal stability and antimicrobial property of treated and untreated cotton fabric. It was observed that silica nanoparticles coated fabric showed substantial thermal stability at 1 % Silica NPs comparatively treated with 2% and 3% silica NPs due to clustering phenomena. Antimicrobial property, confirmatory test as positive control of treated fabric shown substantial increased in antibacterial activity in solutions containing silica NPs as compared to the ethanol solution. Moreover, 76 green profiling score of synthesized method was evaluated by Analytical Eco-Scale tool.

Effect of acid-thermal coupling on the chemical structure and wettability of coal: An experimental study

Coal is the primary fossil fuel in China's energy sector. As the amount of mining continues to increase, the high concentration of dust generated poses a severe threat to equipment and frontline workers. The coupling influence of HCl and temperature on the structure and wettability of coal were conducted by experiments. The phenomenon indicates that the contact angle between coal treated with HCl of different temperatures and water is reduced, the settling distance in an aqueous solution is longer, and the effect is significant with the increase of temperature, demonstrating the acid-thermal coupling solution improves the wettability of coal. Secondly, detailed analysis of coal functional groups and surface element, shows that the percentage of hydrophilic groups increased, such as OH⋯O, free –OH, and hydrophobic groups were destroyed, such as the asymmetric deformation vibration of adjacent H. The L, ‘C', and DOC show an increasing trend, while I first increase and then decrease by analyzing the trends of IR indices of coal. The conclusions prove that the degree of coal deterioration changed after treatment with acid-thermal coupling conditions. The influence mechanism of acid-thermal coupling solution on coal was explored to provide ideas for improving the wettability of coal from the source.