The initial value problem for the quantum Zakharov equation in three di- mensions is studied. The existence and uniqueness of a global smooth solution are proven with coupled a priori estimates and the Galerkin method.
The initial value problem for the quantum Zakharov equation in three di- mensions is studied. The existence and uniqueness of a global smooth solution are proven with coupled a priori estimates and the Galerkin method.
A graph G is k-vertex-critical if χ(G) = k but χ(G − v) 1, H2)-free if it contains no induced subgraph isomorphic to H1 nor H2. A W4 is the graph consisting of a C4 plus an additional vertex adjacent to all the vert...
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We report enhanced accuracy in isotope-shift (IS) measurement using sympathetic cooling, demonstrated with Yb+170,172,174,176 transitions at 369 and 935 nm. Considering only type-A uncertainties, sympathetic cooling a...
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We report enhanced accuracy in isotope-shift (IS) measurement using sympathetic cooling, demonstrated with Yb+170,172,174,176 transitions at 369 and 935 nm. Considering only type-A uncertainties, sympathetic cooling achieves 30- and 200-fold improvements in IS measurement accuracy at 369 and 935 nm compared with previous single-ion results. Our measurements remain the most accurate to date including type-B uncertainties. King-plot analysis yields model-independent IS factors for these transitions [F369=−12.3(8) GHz/fm2, K369=−1800(1400) GHz u, F935=30.7(2.0) GHz/fm2, and K935=12900(3000) GHz u] and their ratio [F935F369=−2.498(4)] along with K935−K369F935F369=8410(90) GHz u, representing a 17-fold improvement. More reliable nuclear charge radii for Yb170–174,176 are also determined with an accuracy of 0.01 fm2. This paper complements collinear laser spectroscopy, introduces a robust approach for researching unstable isotopes, and supports applications of sympathetic cooling in trapped-ion quantum computers and quantum frequency standards.
Plant-based essential oils are complex natural products composed of volatile compounds with wide applications in food, cosmetics, and pharmaceuticals. Their bioactive properties, including antimicrobial, antioxidant, ...
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Plant-based essential oils are complex natural products composed of volatile compounds with wide applications in food, cosmetics, and pharmaceuticals. Their bioactive properties, including antimicrobial, antioxidant, and anti-inflammatory effects, make them promising candidates for food flavoring, preservation, and therapeutic uses. Variations in chemical composition are influenced by geographical, climatic, and extraction factors, necessitating further investigation into their functional roles. This review aims to explore the versatile applications of plant-based essential oils, emphasizing their use in food flavoring, culinary practices, and health benefits. The paper highlights their potential as natural preservatives, flavor enhancers, and bioactive agents, while also addressing challenges such as toxicity, allergenicity, and interactions with food components. A comprehensive literature review was conducted to analyze studies on the extraction methods, chemical compositions, and biological activities of essential oils. Data was gathered to evaluate their antimicrobial, antioxidant, and preservative properties, along with their impact on food quality and safety. Essential oils exhibit significant antimicrobial and antioxidant activities, enabling their use as natural preservatives in food systems, active packaging, and edible coatings. Their incorporation into products such as cheese, ice cream, and beverages has demonstrated enhanced sensory attributes and prolonged shelf life. Encapsulation techniques have shown promise in minimizing interactions with food matrices, ensuring stability, and preserving bioactivity. Plant-based essential oils represent versatile natural additives with functional and sensory benefits. Their antimicrobial, antioxidant, and flavor-enhancing properties support their use in food preservation and flavoring. Encapsulation techniques effectively address challenges related to solubility and stability, enhancing their practical applications
It is presented in this paper that the new design and its analysis of finite difference domain decomposition algorithms for the two-dimensional heat equation, and the numerical results have shown the stability and acc...
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It is presented in this paper that the new design and its analysis of finite difference domain decomposition algorithms for the two-dimensional heat equation, and the numerical results have shown the stability and accuracy of the algorithms, where SauFyev asymmetric schemes have been used at the interface points. The Algorithm II in this paper has further extended those developed by Dawson and the others, Zhang and Shen.
Semiclassical limit to the solution of transient bipolar quantum drift-diffusion model in semiconductor simulation is discussed. It is proved that the semiclassical limit of this solution satisfies the classical bipol...
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Semiclassical limit to the solution of transient bipolar quantum drift-diffusion model in semiconductor simulation is discussed. It is proved that the semiclassical limit of this solution satisfies the classical bipolar drift-diffusion model. In addition, the authors also prove the existence of weak solution.
The following coupled Schrodinger system with a small perturbationis considered, where β and ε are small parameters. The whole system has a periodic solution with the aid of a Fourier series expansion technique, and...
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The following coupled Schrodinger system with a small perturbation
is considered, where β and ε are small parameters. The whole system has a periodic solution with the aid of a Fourier series expansion technique, and its dominant system has a heteroclinic solution. Then adjusting some appropriate constants and applying the fixed point theorem and the perturbation method yield that this heteroclinic solution deforms to a heteroclinic solution exponentially approaching the obtained periodic solution （called the generalized heteroclinic solution thereafter）.
By molecular dynamics simulations employing an embedded atom method potential, we have investigated structural transformations in single crystal A1 caused by uniaxial strain loading along the [001], [011] and [111] di...
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By molecular dynamics simulations employing an embedded atom method potential, we have investigated structural transformations in single crystal A1 caused by uniaxial strain loading along the [001], [011] and [111] directions. We find that the structural transition is strongly dependent on the crystal orientations. The entire structure phase transition only occurs when loading along the [001] direction, and the increased amplitude of temperature for [001] loading is evidently lower than that for other orientations. The morphology evolutions of the structural transition for [011] and [111] loadings are analysed in detail. The results indicate that only 20% of atoms transit to the hcp phase for [011] and [111] loadings, and the appearance of the hcp phase is due to the partial dislocation moving forward on {lll}fcc family. For [011] loading, the hcp phase grows to form laminar morphology in four planes, which belong to the {111}fcc family; while for [111] loading, the hcp phase grows into a laminar structure in three planes, which belong to the {111}fcc family except for the （111） plane. In addition, the phase transition is evaluated by using the radial distribution functions.
Thresholding is an important form of image segmentation and is a first step in the processing of images for many applications. The selection of suitable thresholds is ideally an automatic process, requiring the use of...
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Thresholding is an important form of image segmentation and is a first step in the processing of images for many applications. The selection of suitable thresholds is ideally an automatic process, requiring the use of some criterion on which to base the selection. One such criterion is the maximization of the information theoretic entropy of the resulting background and object probability distributions. Most processes using this concept have made use of the one-dimensional (1D) grey-level histogram of the image. In an effort to use more of the information available in the image, the present approach evaluates two-dimensional (2D) entropies based on the 2D (grey-level/local average grey-level) "histogram" or scatterplot. The 2D threshold vector that maximizes both background and object class entropies is selected.
We propose a five-parameter dumbbell model to describe the fusion and fission processes of massive nuclei, where the collective variables are： distance ρ between center-of-mass of two fusing nuclei, neck parameter ...
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We propose a five-parameter dumbbell model to describe the fusion and fission processes of massive nuclei, where the collective variables are： distance ρ between center-of-mass of two fusing nuclei, neck parameter ν, asymmetry D, two deformation variables β1 and β2. The present model has macroscopic qualitative expression of polarization and nuclear collision of head to head, sphere to sphere, waist to waist and so on. The conception of ＂projectile eating target＂ based on open mouth and swallow is proposed to describe nuclear fusion process, and then our understanding of the probability of fusion and quasi-fission is in agreement with some previous work. The calculated fission barriers of a lot of compound nuclei are compared with the experimental data.
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