A possible power output estimation based on material constants in piezoelectric vibration-based generators is proposed. A modified equivalent circuit model of the generator was built and was validated by the measurement results in the generator fabricated using potassium sodium niobate-based and lead zirconate titanate (PZT) ceramics. Subsequently, generators with the same structure using other PZT-based and bismuth-layered structure ferroelectrics ceramics were fabricated and tested. The power outputs of these generators were expressed as a linear functions of the term composed of electromechanical coupling coefficients k(sys)(2) and mechanical quality factors Q*(m) of the generator. The relationship between device constants (k(sys)(2) and Q*(m)) and material constants (k(31)(2) and Q(m)) was clarified. Estimation of the power output using material constants is demonstrated and the appropriate piezoelectric material for the generator is suggested.
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http://dx.doi.org/10.1109/TUFFC.2011.2023 | DOI Listing |
iScience
January 2025
Ningbo Sunpu Led Co., Ltd., Ningbo 315000, China.
Multiple channels are designed for dimmable LED light sources with color temperatures ranging from 2,700 to 6,500 K. However, issues such as Delta uv (D) values <0, lower brightness, luminous efficacy, and color rendering index (CRI), lower power density, exceeding the standard deviation of color matching (SDCM), unconstant power, poor color consistencies, and high costs persist. We present a three-channel LED light source featuring an integrated chip-on-board (COB) package structure.
View Article and Find Full Text PDFFood Res Int
February 2025
College of Food Science and Engineering, Henan University of Technology, Zhengzhou 450001, China; Wilmar (Shanghai) Biotechnology Research and Development Center Co., Ltd., Pudong New District, Shanghai 200137, China. Electronic address:
The effects of temperature, humidity, and UV irradiation on the accelerated oil oxidation of chicken seasoning (CS) were investigated, aiming to establish a method for evaluating its storage stability. Key oxidation indicators, such as peroxide value (POV), fatty acid profile, and volatile aldehydes, were measured to assess the degree of oil oxidation. The results indicated that oil oxidation of CS is not significantly accelerated by temperatures of 50-80 °C due to the inhibitory effects of the Maillard reaction.
View Article and Find Full Text PDFSci Rep
January 2025
Applied Optics Laboratory, Institute of Optics and Precision Mechanics, University Setif 1, Setif, 19000, Algeria.
This prediction evaluates the different physical characteristics of magnetic materials XFeO (X = Mg, Ca and Sr) by using density functional theory (DFT). The generalized gradient approximation (GGA) approach is chosen to define the exchange and correlation potential. The structural study of the compounds XFeO (X = Mg, Ca and Sr) shows that the ferromagnetic phase is the more stable ground state, where all the parameters of the network are given at equilibrium.
View Article and Find Full Text PDFEnviron Res
January 2025
Faculty for Chemistry, Department of Physical Chemistry, University of Vienna, Vienna, Austria.
Composite photocatalysts based on metal nanoparticles and functional polymers attract much attention compared to inorganic photocatalysts. In this study, a reusable magnetite/anion exchanger (FeO/PPE-2) functional material is synthesized by a hydrothermal method, and its photocatalytic activity is evaluated for the photocatalytic degradation of Rhodamine B (RhB). The results from materials characterization confirm a well-defined morphology of magnetic FeO/PPE-2 functional material and the formation of FeO nanocrystals with different shapes and sizes on the surface of anion exchange material (PPE-2).
View Article and Find Full Text PDFBiomacromolecules
January 2025
School of Physics and Astronomy, University of Leeds, Leeds LS2 9JT, U.K.
Enzymes are attractive as catalysts due to their specificity and biocompatibility; however, their use in industrial and biomedical applications is limited by stability. Here, we present a facile approach for enzyme immobilization within "all-enzyme" hydrogels by forming photochemical covalent cross-links between the enzyme glucose oxidase. We demonstrate that the mechanical properties of the enzyme hydrogel can be tuned with enzyme concentration and the data suggests that the dimeric nature of glucose oxidase results in unusual gel formation behavior which suggests a degree of forced induced dimer dissociation and unfolding.
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