Semi-empirical Relations Research Articles

Influence of hygrothermal aging on the lifetime and mechanical properties of GFRP/Al adhesive joints

The study aimed to investigate the impact of hygrothermal aging on the degradation of mechanical properties and predict the lifetime of adhesive joints between aluminum alloy (AA6061) and glass fiber-reinforced epoxy (GFRP) composites. The adhesive joints were prepared in a single lap joint (SLJ) configuration and subjected to hygrothermal conditions to induce aging. Immersion tests were conducted at a water temperature of 70 °C with varying aging periods (10, 18, 40, 54, 60, and 75 days) to assess the long-term performance and predict the lifetime of the joints. The tensile and shear strength of the adhesive joints were evaluated using a tensile test. The test was performed at room temperature (RT) with a speed rate of 1.3 mm/min. Among the different methods available for lifetime prediction, a semi-empirical approach was selected to analyze the changes in the mechanical properties of the adhesive joints. A comprehensive comparison was made between aged and unaged specimens. The experimental results revealed a reduction in the ultimate tensile and shear strength of the adhesive bonds over the 75-day aging period. The semi-empirical relationship used for long-term durability prediction of adhesive joint structures indicated a 78 % decrease in ultimate tensile strength for the adhesive joints over a one-year aging period. This highlights the significant influence of hygrothermal aging on the mechanical properties of the investigated adhesive joints. During the aged periods, various failure modes were observed, including adhesive failure, cohesive failure, and structural failure.

Shaking Table Test and Numerical Modeling of Seismic Behavior of Rectangular Tunnel Structures Embedded in Soft Clay

In this paper, a series of 1-g shaking table model tests were carried out to investigate the seismic behavior of a relatively stiff rectangular tunnel structure installed in soft clay bed, accounting for different ground motions with varying peak accelerations. Using a validated numerical analysis procedure, a suite of three-dimensional (3D) finite element (FE) analyses was performed to systematically study the factors of tunnel burial depth, seismic intensity, flexural rigidity of the middle column and tunnel wall thickness on the seismic response of rectangular tunnel structures installed in clayey ground. It was found that, with the increasing burial depth, the seismic response of rectangular tunnel structure became more intense due to the increased inertial force arising from the overlying clay; in terms of improving the seismic performance of tunnel structure, increasing tunnel wall thickness seemed more effective than increasing flexural rigidity of the middle column. Furthermore, it was found that the existing simplified approaches generally tended to overestimate the earthquake-induced racking distortions of rectangular tunnels installed in clayey ground. A new semi-empirical relationship was derived for better correlating the racking ratio with flexibility ratio for rectangular tunnels embedded in soft clays, which could provide a useful reference for the seismic design and risk assessment of similar clay-tunnel systems.

A simple hot wire temperature drift correction based on temperature sensitivity applied to a turbulent shear layer

A procedure is proposed to correct temperature drift for hot wire anemometry measurements in turbulent fields where the facility is not equipped with temperature control. The procedure consists of evaluating the wire sensitivity to the temperature by building a voltage-temperature curve. The voltages of both the calibration points and the measurement points are corrected, shifting the voltage values to an arbitrary reference temperature. The correction can be applied to the instantaneous voltages by performing synced temperature measurements with constant current anemometry or constant voltage anemometry cold wire. The efficacy of the method is tested on a turbulent shear layer that develops on the side of an open jet wind tunnel not equipped with temperature control. The velocity statistics show a good match with respect to reference particle image velocimetry measurements, evidencing the self-similarity of the shear layer in contrast with the non-corrected data and the data corrected using the semi-empirical and analytical relation based on King's law modification. A correction based only on the temperature statistics shows indistinguishable results with respect to the instantaneous correction.

An analytical approach for designing sCO2 centrifugal compressors using the loss-integrated throughflow method

Several studies have focused on the analytical modeling of centrifugal compressors. These models are commonly used in design, optimization and evaluation of rotor geometry. Existing models, which rely on either the meanline method (1D model) or the streamline curvature-based throughflow method (2D model) combined with semi-empirical pressure loss relations, are closed-loop models that do not account for pressure loss distribution along the blade channel. Additionally, these models simplify the rotor’s three-dimensional geometry, focusing primarily on the β angle and meanline length. To address these limitations, we introduce an open-loop analytical approach called the ’loss-integrated throughflow method’ (LITM). This method computes pressure losses step-by-step along the blade’s channel geometry using the three-dimensional cross-section of the rotor as input data. The motivation behind this new approach is to develop an alternative tool for the preliminary design of supercritical CO2 (sCO2) compressors, providing insight into the relation between losses and rotor geometry beyond just the β angle and meanline length. In the present work we compare simulation results with a one-dimensional (1D) mathematical model that has been validated against experimental data for sCO2. We compare three sets of rotors, where each set shares identical β angles and meanline lengths. When compared against the 1D model, our model yields deviations ranging from 2.8% to 21.9% for rotors with matching meanline lengths and β angles. This suggests that factors other than the variables previously considered influence pressure losses. As a result of this study, we conclude that the proposed analytical model offers potential to refine the preliminary design for sCO2 rotors.

CFD Modeling of Aerosol Transport and Deposition Using a Drift-Flux Model

Aerosol transport and deposition are important processes in modeling of accident scenarios for a small modular reactor. An aerosol drift-flux model is attractive because it is computationally less expensive than Lagrangian particle tracking. It must be determined, however, how well it performs when implemented in a commercial computational fluid dynamics (CFD) code. This work presents results of modeling aerosol transport and deposition using a full Eulerian three-dimensional drift-flux model implemented in the commercial CFD code STAR-CCM+. The forces due to gravity and thermophoresis are included in the present drift-flux model along with Brownian motion and turbulent diffusion. The forces are added as a source term to a passive scalar transport equation. In addition, a drift velocity representing the forces is used in a built-in electrochemical species transport equation. The results of these two approaches are compared. An appropriate deposition velocity is used to calculate the aerosol concentration deposited on surfaces. The semiempirical relation proposed by Lai and Nazaroff (2000) is used to compute the deposition velocity due to gravitational settling, and the present results are compared with the experimental and numerical data obtained from the work of Chen et al. (2006). It was found that the concentration profile obtained from the present drift-flux model showed reasonable agreement with the literature data. A thermophoresis model showed good agreement when compared with the analytical solution of Nazaroff and Cass (1987). In addition to the particle concentration results, this work presents details of the drift-flux model implementation and the bulk flows. These extra details will enable comparisons by others developing similar models.

Molecular interaction study using density, viscosity, speed of sound and FT-IR in 2-methyl-2-butanol + alkoxyethanols: Experimental and modelling approach

In this article, the intermolecular interactions in the binary liquid mixtures of 2-methyl-2-butanol with alkoxyethanols viz., 2-ethoxyethanol, 2-propoxyethanol and 2-butoxyethanol have been interpreted using thermophysical properties. Density (ρ), viscosity (η) and speed of sound (u) of pure components and their binary mixtures have been measured over the entire range of composition at 298.15, 303.15 and 308.15 K and at pressure p = 0.10 MPa. The experimental data were used to calculate the thermophysical properties such as excess molar volume (VmE), excess molar isentropic compressibility (Ks,mE), excess speed of sound (uE), deviation in viscosity (Δη) and excess Gibbs free energy of activation for viscous flow (ΔG∗E). The changes in these properties with composition and temperature of the liquid mixtures were discussed in terms of intermolecular interactions. Also, the effect of increase in alkyl chain length of alkoxyethanol molecule on these properties has been studied. The excess functions and their deviations have been correlated using Redlich-Kister type polynomial equation. The experimentally measured values of viscosities have been correlated with various semi-empirical relations such as Grunberg-Nissan, Tamura-Kurata, Hind et al., Katti-Chaudhri, McAllister’s two parameter model, Heric-Brewer and McAllister’s three parameter model. Apart from this, Prigogine-Flory-Patterson (PFP) theory has been used for the estimation of VmE values for studied binary mixtures. FT-IR spectra of these liquid mixtures have also been studied.

Protein Adsorption on Solid Surfaces: Data Mining, Database, Molecular Surface-Derived Properties, and Semiempirical Relationships.

Protein adsorption on solid surfaces is a process relevant to biological, medical, industrial, and environmental applications. Despite this wide interest and advancement in measurement techniques, the complexity of protein adsorption has frustrated its accurate prediction. To address this challenge, here, data regarding protein adsorption reported in the last four decades was collected, checked for completeness and correctness, organized, and archived in an upgraded, freely accessible Biomolecular Adsorption Database, which is equivalent to a large-scale, ad hoc, crowd-sourced multifactorial experiment. The shape and physicochemical properties of the proteins present in the database were quantified on their molecular surfaces using an in-house program (ProMS) operating as an add-on to the PyMol software. Machine learning-based analysis indicated that protein adsorption on hydrophobic and hydrophilic surfaces is modulated by different sets of operational, structural, and molecular surface-based physicochemical parameters. Separately, the adsorption data regarding four "benchmark" proteins, i.e., lysozyme, albumin, IgG, and fibrinogen, was processed by piecewise linear regression with the protein monolayer acting as breakpoint, using the linearization of the Langmuir isotherm formalism, resulting in semiempirical relationships predicting protein adsorption. These relationships, derived separately for hydrophilic and hydrophobic surfaces, described well the protein concentration on the surface as a function of the protein concentration in solution, adsorbing surface contact angle, ionic strength, pH, and temperature of the carrying fluid, and the difference between pH and the isoelectric point of the protein. When applying the semiempirical relationships derived for benchmark proteins to two other "test" proteins with known PDB structure, i.e., β-lactoglobulin and α-lactalbumin, the errors of this extrapolation were found to be in a linear relationship with the dissimilarity between the benchmark and the test proteins. The work presented here can be used for the estimation of operational parameters modulating protein adsorption for various applications such as diagnostic devices, pharmaceuticals, biomaterials, or the food industry.

Lattice Boltzmann simulation of breaking waves

Water wave breaking at the ocean’s surface is a turbulent phenomenon and encompasses a wide range of physical processes such as generation of bubbles/drops with different spatio-temporal scales. In the present study, breaking of periodic waves in deep water regime has been simulated using phase-field lattice Boltzmann method (LBM). Compared to direct Navier–Stokes equation based numerical models, the present LB model is Poisson-free and explicit in time integration. Both the flow field and interface are solved using LBM with two sets of distribution functions. The normalized pressure-velocity formulation is used for the flow field, whereas the conservative Allen–Cahn equation is used to capture the interface. An impulsively started wave approach with Stokes third order wave profile has been used to initiate the breaking process. Through systematic variation of Weber number and initial steepness, the effect of surface tension on the kinematic, geometric, and energy dissipation characteristics has been studied for three breaker types, viz., spilling, weak plunging, and plunging breakers. The results are in good agreement with the past experimental observations and direct numerical simulation. In particular, the obtained breaking strength for different Weber numbers agrees well with the semi-empirical relation used in a wind-wave forecasting models.

Exploration of the optical characteristics in sol-gel synthesized europium-doped zinc oxide thin films for potential optoelectronic use: a comprehensive characterization approach

Abstract In this study, we present our findings on the spin coated pure Zinc-Oxide (ZnO) nanowire arrays and Europium doped ZnO (Eu3+: ZnO) nanostructure thin films. These arrays were grown on soda lime (silica) coated glass substrate. We conducted a comprehensive analysis of the structural and optical properties of the as-synthesized nanostructures. The characterization techniques included x-ray Diffraction, FESEM Analysis, Raman Spectroscopy, Photoluminescence and UV–vis Analysis. The XRD findings indicate the incorporation of Europium (Eu3+) into the ZnO crystalline lattice, potentially replacing Zn2+ ions. This doping with Europium (Eu3+) led to a reduction in crystalline size, as determined by Scherrer’s equation decreasing from 48 nm to 28 nm demonstrates a decrease in defects within the films. Raman Shift analysis revealed changes in the optical properties of films with inclusion of Europium in host matrix. Photoluminescence studies demonstrated a distinctive 5D0 to 7F2 transition arising from the Eu3+ ions, observed at approximately 612 nm. We have thoroughly examined the optical characteristics of both Europium-doped and pure ZnO thin films through a systematic study. The optical properties were assessed by analyzing the absorption spectra (220–600 nm) and transmission spectra within the wavelength range of 200 to 1200 nm. The film exhibited an impressive 80% transparency, particularly noteworthy for window layer application. The refractive index (n), extinction coefficient (k) and all other associated parameters were found to be impacted by the doping of Europium. The refractive index dispersion relation has been explored using a single oscillator model. Furthermore, the non-linear optical susceptibility (χ 3) and non-linear refractive index were computed using semi-empirical relationships based on the linear optical parameters. The Europium (Eu3+) doping in ZnO led to an increase in the χ 3 value elevating it from 4.07 × 10–1° to 5.91 × 10–1° e.s.u. These findings suggest that Europium-doped ZnO nanostructures have the potential to be a promising platform for the development of efficient multispectral light-emitting diodes (LED’s) and optical devices.

Calculation of the half-life of proton radioactivity using the empirical formula depending on angular momentum

In this paper, considering the power of the daughter nuclear charge as a function of the orbital angular momentum taken away by the emitted proton, we propose a formula for the half-life of proton radioactivity. In this formula, we have three coefficients with orbital angular momentum dependence. Using experimentally measured half-lives for 8 proton emitters with [Formula: see text], 14 proton emitters with [Formula: see text] and 18 proton emitters with [Formula: see text], we have obtained the coefficients. The root mean square deviations of our formula respect to the experimental value are found 0.2514, 0.4442 and 0.1846 for emitters [Formula: see text], 2 and 5, respectively. We have compared our results with Sreeja formula, the semiempirical relation of Hatsukawa and theoretical models such as the Coulomb and proximity potential model (CPPM) and the Gamow-like model. The better agreement with experimental data was observed for our formula in comparison with other theoretical models and Sreeja and Hatsukawa formulas.

Improved empirical formula for spontaneous fission half-lives

The spontaneous fission (SF) half-lives of all 96 experimentally accessible SF emitters were examined. The SF emitters are classified as even Z-even A, odd Z-even A, odd Z-odd A and even Z-odd A. A plot of [Formula: see text] versus [Formula: see text] demonstrates a straight line, where k is variable. The [Formula: see text] values produced in this study are compared to all other semi-empirical relations such as Ren et al., [Nucl. Phys. A 759, 64 (2005)], Xu et al., [Phys. Rev. C 78, 044329 (2008)], Santhosh et al., [Nucl. Phys. A 832, 220 (2010)] and Karpov et al., [Int. J. Mod. Phys. E 21, 1250013 (2012)] available in the literature. When compared to earlier semi-empirical equations accessible in the literature, the new formula shows reduced uncertainty in standard deviation in the case of Odd Z-even A and even Z-Odd A nuclei. When compared to other sets of combinations (even Z-even A, and odd Z-odd A nuclei), this study more accurately reproduces the experimental SF half-lives for even Z-odd A and odd Z-even A nuclei with smaller [Formula: see text] in the atomic number range 9[Formula: see text]12 and mass number range 23[Formula: see text]84.

Chemical Space Covered by Applicability Domains of Quantitative Structure-Property Relationships and Semiempirical Relationships in Chemical Assessments.

A significant number of chemicals registered in national and regional chemical inventories require assessments of their potential "hazard" concerns posed to humans and ecological receptors. This warrants knowledge of their partitioning and reactivity properties, which are often predicted by quantitative structure-property relationships (QSPRs) and other semiempirical relationships. It is imperative to evaluate the applicability domain (AD) of these tools to ensure their suitability for assessment purpose. Here, we investigate the extent to which the ADs of commonly used QSPRs and semiempirical relationships cover seven partitioning and reactivity properties of a chemical "space" comprising 81,000+ organic chemicals registered in regulatory and academic chemical inventories. Our findings show that around or more than half of the chemicals studied are covered by at least one of the commonly used QSPRs. The investigated QSPRs demonstrate adequate AD coverage for organochlorides and organobromines but limited AD coverage for chemicals containing fluorine and phosphorus. These QSPRs exhibit limited AD coverage for atmospheric reactivity, biodegradation, and octanol-air partitioning, particularly for ionizable organic chemicals compared to nonionizable ones, challenging assessments of environmental persistence, bioaccumulation capability, and long-range transport potential. We also find that a predictive tool's AD coverage of chemicals depends on how the AD is defined, for example, by the distance of a predicted chemical from the centroid of the training chemicals or by the presence or absence of structural features.

Method of calculation of satellite flow parameters behind the point of Mach reflection

A mathematical model for the calculation and express analysis of triple configurations of air shock waves arising from an “elevated” explosion of a condensed high-energy material is presented. The considered blast waves with a long duration of the positive phase (compression phase) can take place in industrial and agricultural applications: in the explosion of fuel-air mixtures, explosive dust in elevators and granaries, as well as high-energy materials for agricultural and industrial applications based on ammonium nitrate and explosive saltpetre mixtures with petroleum products. The developed mathematical model uses exact and semi-empirical relationships developed earlier in the theory of optimal shock wave systems.

Resistência ao cisalhamento longitudinal de lajes mistas modeladas em escala real considerando a geometria das mossas por meio do método dos elementos finitos

Abstract Slabs with cast-in-place steel formwork are composite structural elements composed of concrete and steel. The horizontal shear failure mode is the most common in composite slabs based on numerous experimental studies. This failure mode consists of loss of adherence and mechanical contact at the interface of the composite system and often occurs before the system reaches its full bending capacity. Thus, the design of this constructive system is determined by the value of the longitudinal shear strength, which can be computed by the semi-empirical so-called traditional m-k method based on the four-point bending test proposed by several standards. One of the most known factors to influence the longitudinal shear strength is the geometry of embossments present in the steel work. Calibrated computational simulation using the finite element method can be an alternative way to simulate this type of test. The present work modified and adapted a methodology explicitly including the geometry of embossments in the analysis in order to use materials and products with characteristics available to structural engineers in Brazil and used this methodology to derive m-k coefficients. This is being made with the objective of numerically simulating the effect of relevant parameters for determining the longitudinal shear strength at the concrete-steel interface of composite slabs. Force versus slip, force versus displacement graphs were obtained and the m-k coefficient values found were compared with those of other authors in the literature. The simulations presented values consistent with the literature and in relation to the rupture mode by longitudinal shear, the numerical simulations performed presented ultimate strengths with goodness-of-fit measured by the conventional coefficient of determination, reaching a good value for the semi-empirical relation using the results of the finite element data.

The response of glass fibre reinforced PEKK laminates subjected to single and multiple impact loading

This paper presents a study on the impact behaviour of newly-developed composites based on S-glass fibre reinforced PEKK (GF/PEKK) composites subjected to single and repeated impact loading. The laminates, with a thickness of 2 mm and fibre weigh fraction of 60 wt%, were manufactured by stacking eight plies of GF/PEKK woven prepregs using a hot compression moulding technique, and impacted centrally using a drop-weight apparatus. Beginning with a single impact test, these samples were subjected to repeated impacts using the same projectile and energy until full perforation was achieved. During each test, the impact response characteristics, contact force, velocity, displacement and energy absorption with respect to time were measured and recorded. The results show that, for a single impact test, the absorbed energy increases significantly at low impact energies, while repeated impacts lead to a decrease in the values of peak force and stiffness of the composite panels. Here, up to 5 times of energy can be absorbed over multiple low energy impacts compared to that required to perforate the target with a single impact. For multiple impacts at different impact energy levels, accumulation of damaged area increases rapidly around the impact location up to perforation failure (e.g. the rate of damage from 2 mm2 per impact at 1 J case jumping to 25 mm2 per impact at 2 J case, further to 68 mm2 per impact at 3 J case). The rate of damage progression (per impact) appears to be related strongly to the rate of energy absorption. The continuous nature of the absorbed energy and damage progression over multiple impacts suggest that semi-empirical analytical relationships, similar to that used in a fatigue analysis, could be useful in providing a means of assessing impact damage in a laminated structure and predicting the remaining ‘impact fatigue’ life.

Effect of inlet throttling on thermohydraulic instability in a large scale water-based RCCS: A system-level analysis with RELAP5-3D

This paper presents results from system-level modeling of a water-based reactor cavity cooling system using RELAP5-3D. The computational model is benchmarked with experimental data from a half-scale RCCS test facility at Argonne National Laboratory. The model prediction is first compared with a two-phase oscillatory baseline experimental case where mixed accuracy is obtained. The model shows reasonable prediction of mass flow rate, pressure, and temperature but significant overprediction of void fraction. The model prediction is then compared with a fault case where the inlet of the risers is gradually reduced using a throttling valve. As the valve is closed, the model is able to predict some major flow phenomena observed in the experiment such as the dampening of oscillations, the reintroduction of oscillations, as well as boiling, flashing, and geysering in the risers. However, the timeline of these events are not well captured by the model. The model is also used to investigate the evolution of flow regime in the chimney. This work highlights that the semi-empirical constitutive relations used in RELAP-3D could have a strong influence on the accuracy of the model in two-phase oscillatory flows.

Coupled bio-chemo-hydro-mechanical modeling of microbially induced calcite precipitation process considering biomass encapsulation using a micro-scale relationship

Geomaterials with inferior hydraulic and strength characteristics often need improvement to enhance their engineering behaviors. Traditional ground improvement techniques require enormous mechanical effort or synthetic chemicals. Sustainable stabilization technique such as microbially induced calcite precipitation (MICP) utilizes bacterial metabolic processes to precipitate cementitious calcium carbonate. The reactive transport of biochemical species in the soil mass initiates the precipitation of biocement during the MICP process. The precipitated biocement alters the hydro-mechanical performance of the soil mass. Usually, the flow, deformation, and transport phenomena regulate the biocementation technique via coupled bio-chemo-hydro-mechanical (BCHM) processes. Among all, one crucial phenomenon controlling the precipitation mechanism is the encapsulation of biomass by calcium carbonate. Biomass encapsulation can potentially reduce the biochemical reaction rate and decelerate biocementation. Laboratory examination of the encapsulation process demands a thorough analysis of associated coupled effects. Despite this, a numerical model can assist in capturing the coupled processes influencing encapsulation during the MICP treatment. However, most numerical models did not consider biochemical reaction rate kinetics accounting for the influence of bacterial encapsulation. Given this, the current study developed a coupled BCHM model to evaluate the effect of encapsulation on the precipitated calcite content using a micro-scale semiempirical relationship. Firstly, the developed BCHM model was verified and validated using numerical and experimental observations of soil column tests. Later, the encapsulation phenomenon was investigated in the soil columns of variable maximum calcite crystal sizes. The results depict altered reaction rates due to the encapsulation phenomenon and an observable change in the precipitated calcite content for each maximum crystal size. Furthermore, the permeability and deformation of the soil mass were affected by the simultaneous precipitation of calcium carbonate. Overall, the present study comprehended the influence of the encapsulation of bacteria on cement morphology-induced permeability, biocement-induced stresses and displacements.

The competition between α-decay and spontaneous fission for even–even isotopes of superheavy nuclei in the range 106≤Z≤124

The [Formula: see text]-decay and spontaneous fission (SF) half-lives for even–even isotopes of superheavy nuclei in the range [Formula: see text] are predicted using nuclear double-folding and Coulomb potentials. The [Formula: see text]-decay half-lives are computed based on WKB approximation for tunneling probability through potential barrier. The half-lives of SF have also been calculated using a semi-empirical relation constructed by Santhosh et al. [Nucl. Phys. A 832, 220 (2009)]. Our calculated half-lives of cold SF and [Formula: see text]-decay are compared with the available experimental data. This comparison indicates that our obtained half-lives are in good agreement with the available experimental data. The competition between [Formula: see text]-decay and SF is also analyzed in detail and the decay modes are predicted for the unknown cases. Variation of [Formula: see text]-decay and SF half-lives with mass number of the parent isotopes for each nucleus revealed the major role played with shell effect.

Method for quantifying catechin in a strawberry extract by measuring optical absorbance, at high sensitivity, under the effect of wavelength and concentration

Catechin is considered a powerful antioxidant, and its rapid quantification could help urgently prevent inflammatory and coronary heart diseases. Consequently, the UV–Vis absorption spectrophotometry assay technique could serve this need for rapid detection.For this reason, we have carefully studied the possibility of dosing this antioxidant found in strawberry extract with precision, despite its chemical complexity.In the dosage technique used; sometimes the dilution of the solutions could be the way to resolve a specific quantification problem such as catechin in strawberry extract. This is quite particular, when the optical extinction coefficient of the target substance is very low compared to the extinction coefficients of the other chemical compounds in the complex mixture, because at a certain dilution the absorption spectrum of the molecule could appear, specifically, with its total spectral form or at least at one of these wavelengths.In this article, we will study the possibility of rapidly measuring catechin from strawberry extract by spectrophotometry in UV–VIS, while reformulating the Beer-Lambert law in a new form where the extinction coefficient did not depend not only of the chemical nature of the solute and the solvent but also of the excitation wavelength (ε(λ), Eq. (9)).A catechin-methanol solution is taken as a reference to study the spectral variation due to the various dilutions of the solution and the determination of a limiting concentration where the excitation wavelength becomes constant (203 nm), thus the extinction coefficient of the catechin, denoted ε0, but the measurement sensitivity is suddenly reduced.A semi-empirical relationship is determined by linearization of the absorbance function which depended on the concentration (C) and the excitation wavelength (ε(λ)).A separation process will be exposed to recover the strawberry extract, as well as its spectral analysis. Finally, a procedure for analyzing any strawberry extract will be presented at the end of this scientific article.

Impact of nuclear rotation corrections on alpha decay half-lives of superheavy nuclei within 98 ≤ Z ≤ 120

The influence of nuclear rotation on the decay half-lives of superheavy nuclei within the range 98≤Z≤120 is investigated using the axially deformed relativistic Hartree-Bogoliubov theory in the continuum (DRHBc) with the PC-PK1 parameter set. The deduced DRHBc decay energies (with and without the rotation effect) are compared with those calculated from the macroscopic-microscopic WS4 and the available experimental binding energies. Six semi-empirical formulae, such as the Viola-Seaborg formula (VSS), the modified Brown formula (mB1), the semi-empirical relationship based on fission theory (SemFIS2), the Royer formula (R), the Wang formula (Wang) and the modified YQZR formula (MYQZR) are employed to estimate the half-lives of α decay. Among these formulae, the half-live predictions of SemFIS2 are found to gradually deviate from the systematic trend beyond Nd=184, showing that the probability of undergoing spontaneous fission is less feasible beyond this point. A minimum is observed at Nd=184, reflecting its neutron shell closure for the mass region considered on the nuclear chart. The results further indicate that, for 98≤Z≤104, the predictions of all semi-empirical formulae are more closely matched to the available experimental data when the rotation effect is taken into account. However, we have demonstrated that the effect of nuclear rotation gradually reduces as the atomic nucleus becomes heavier.