Lime essential oil (EO) nanoemulsions from key lime (Citrus aurantifolia), kaffir lime (Citrus hystrix) and calamansi lime (Citrofortunella microcarpa) were produced by using spontaneous ...emulsification method and their particle size, polydispersity index (PDI), turbidity, morphology and antibacterial properties were investigated. Lime EO nanoemulsions were produced by mixing 5% (v/v) of oil phase (lime EO and corn oil at the ratio of 8:2) with 15% (v/v) of Tween 80 and 80% (v/v) of deionized water using magnetic stirring at 750 rpm and 25 °C. Key lime EO nanoemulsion showed the smallest particle size (21 nm), lowest PDI value (0.444) and lowest turbidity (99.0% of transmittance) followed by kaffir and calamansi lime. Transmission electron microscopy (TEM) micrographs revealed sphere-shaped oil particles with different particle size. Freshly prepared calamansi lime EO nanoemulsion was the most effective against Escherichia coli, Salmonella spp, and Staphylococcus aureus by exhibiting the largest diameter of inhibition zone (8.34, 7.71, and 9.98 mm, respectively). Key lime EO nanoemulsion showed the lowest reduction in the antibacterial activity after 1 month of storage at room temperature. The lime EO nanoemulsions showed great potential to be incorporated into water-based food products and beverages as flavouring and antimicrobial agents.
•Lime essential oil nanoemulsions produced via spontaneous emulsification method.•Stable lime essential oil nanoemulsions (21–60 nm) were produced using Tween 80.•Optimal essential oil to carrier oil ratio of 8:2 was determined.•Lime essential oil composition affected the nanoemulsions' physical properties.•All lime essential oil nanoemulsions exhibited good antibacterial activity.
In this paper, we investigate the long time existence and uniqueness of small solution to d, for d=2,3, dimensional Prandtl system with small initial data which is analytic in the horizontal ...variables. In particular, we prove that d dimensional Prandtl system has a unique solution with the life-span of which is greater than ε−43 if the initial data is of size ε and the value on the boundary of the tangential velocity of the outflow are of size ε53. We mention that the tool developed in 4,5 to make the analytical type estimates and the special structure of the nonlinear terms to this system play an essential role in the proof of this result.
This work is concerned with the compressible micropolar fluids system in three–dimensional space. We consider the asymptotic behavior of the solution to the Cauchy problem near the constant ...equilibrium state provided that the initial perturbation is sufficiently small. Under some assumptions of the initial data, we show that the solution of the Cauchy problem converges to its constant equilibrium state at the exact same L2–decay rates as the linearized equations, which shows the convergence rates are optimal. The proof is based on the spectral analysis of the semigroup generated by the linearized equations and the nonlinear energy estimates.
The paper presents a modal model to describe the interaction between a 4-conductor bundle and wind. A finite-element model of the bundle is used to perform a linear analysis, to extract mode shapes ...and natural frequencies of the system. The motion of the expanded bundle is then described through mode coordinates representing the first horizontal, vertical and torsional modes. Wind tunnel tests were performed adding templates over the cables to mimic the presence of ice over the same conductor bundle; tests allowed to characterize the aerodynamic coefficients of the entire bundle and provided data for the model validation. The model was then applied to a case study to predict the maximum oscillations produced by iced conductor galloping. Time-domain simulations were used for the purpose, together with an alternative approach named energy method; this last directly estimates the amplitude of limit cycles avoiding the integration of the equations of motion and can be much more useful from the engineering point of view.
In the present study, a novel theoretical model is developed, based on the energy method, to predict the equivalent mechanical properties of a new morphing structure with zero Poisson’s ratio, which ...is composed of continuous fiber reinforced composite struts.Due to the employing glass fiber in fabricating the proposed cruciform honeycomb, higher strength than the structures made of pure isotropic materials is obtained. The use of cells with a zero Poisson's ratio also increases the flexural strength of the structure. In the continuation of the paper, by examining the geometric effects on the equivalent properties, a parametric study is performed. Then, using the appropriate failure criterion, the tensile and compressive strength of this network is obtained. The extracted properties are used in nonlinear analysis of the response of morphing structures and to improve the performance of these structures under different loads. It should be noted that in order to validate the relationships developed in this paper, the experimental tests and finite element methods are employed.
Astrocaryum vulgare is an Amazon palm species, popularly known as tucumã. A. vulgare oil has diverse biological purposes, but low solubility in water. Nanoemulsions provide a solution to this ...problem. This study aimed to evaluate the influence of different surfactants on the development of nanoemulsions. To determine the hydrophilic-lipophilic balance (HLB), the influence of different surfactants on nanoemulsification was determined, the region of nanoemulsion formation on the pseudo-ternary phase diagram was analyzed, nanoemulsions were characterized, and the best candidate was subjected to stability assessment. The HLB was 14, and PPG-5-Ceteth-20 and sorbitan oleate were selected as surfactants. The nanoemulsion had a droplet size of 174.1 nm, a polydispersity index of 0.295, and a zeta potential of 20.7. A. vulgare oil is used in the Amazon for countless pharmaceutical applications. We demonstrate the impact of the chemical structure of surfactants, resulting in the formation of nanoemulsions containing A. vulgare oil.
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In this paper, we consider a one‐dimensional porous thermoelastic system with microtemperatures effects and past history term acting only on the porous equation. We show that the system is well‐posed ...in the sens of semigroup and based on the energy method we establish a general decay result for the solutions of the system under an appropriate assumptions on the kernel. Furthermore, our result does not depend on any relationship between the coefficients of the system. The result of this paper improves some results in the literature.
Tunneling underneath is bound to induce the free displacement of surrounding soil, which will further significantly affect the overlying tunnel's deformation. Based on this, a simplified method for ...calculating the deformation of the overlying tunnel due to shield tunnel excavation is proposed. Firstly, the Loganathan formula is selected to solve the additional stress along the pre‐existing tunnel induced by tunneling underlying, then the overlying tunnel is further simplified into an infinitely Euler‐Bernoulli beam resting on the Pasternak foundation. The influence of the lateral soil reaction on the existing tunnel is introduced, then adopting the energy method to describe the soil and tunnel response. The minimum potential energy principle is utilised to solving the variational energy solutions due to new tunnel excavation underlying and further obtain the explicit solutions of tunnel response. The proposed method's effectiveness is confirmed through comparisons with centrifuge tests and field case studies obtained from prior research. In comparison with the Pasternak foundation model degenerated from the proposed method, the outcomes produced using the proposed method align more closely with the measurement data. Further parameter studies show that skew angle between tunnels, depth of existing tunnel, and volume loss rate are significant factors affecting the tunnel behaviors due to tunneling underneath.
In this paper, we study the well-posedness and asymptotic stability to a thermoelastic laminated beam with nonlinear weights and time-varying delay. To the best of our knowledge, there are no results ...on the system and related Timoshenko systems with nonlinear weights. On suitable premises about the time delay and the hypothesis of equal-speed wave propagation, existence and uniqueness of solution is obtained by combining semigroup theory with Kato variable norm technique. The exponential stability is proved by energy method in two cases, with and without the structural damping, by using suitably sophisticated estimates for multipliers to construct an appropriated Lyapunov functional.
We consider the non-relativistic quantum Boltzmann equation for fermions and bosons. Using the nonlinear energy method and mild formulation, we justify the global well-posedness when the density ...function is near the global Maxwellian and vacuum. This work is a generalization and adaptation of the classical Boltzmann theory. Our main contribution is a detailed analysis of the nonlinear operator Q in the quantum context. This is the first piece of a long-term project on the quantum kinetic equations.
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