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661.
Multilayered solid structures made of isotropic, transversely isotropic, or general anisotropic materials are frequently used in aerospace, mechanical, and civil structures. Ultrasonic fields developed in such structures by finite size transducers simulating actual experiments in laboratories or in the field have not been rigorously studied. Several attempts to compute the ultrasonic field inside solid media have been made based on approximate paraxial methods like the classical ray tracing and multi-Gaussian beam models. These approximate methods have several limitations. A new semianalytical method is adopted in this article to model elastic wave field in multilayered solid structures with planar or nonplanar interfaces generated by finite size transducers. A general formulation good for both isotropic and anisotropic solids is presented in this article. A variety of conditions have been incorporated in the formulation including irregularities at the interfaces. The method presented here requires frequency domain displacement and stress Green's functions. Due to the presence of different materials in the problem geometry various elastodynamic Green's functions for different materials are used in the formulation. Expressions of displacement and stress Green's functions for isotropic and anisotropic solids as well as for the fluid media are presented. Computed results are verified by checking the stress and displacement continuity conditions across the interface of two different solids of a bimetal plate and investigating if the results for a corrugated plate with very small corrugation match with the flat plate results. 相似文献
662.
663.
Development of chemical and biochemical sensors is the current need of the society. In this report, we present our investigation
on the development of a label-free fibre-optic biosensor based on evanescent wave absorbance to detect the presence of analytes
such as bacteria, virus and some clinically important proteins. A simple UV-LED (280 nm) and photodetector combination along
with a fibre probe was used for developing cost-effective, user-friendly and field applicable device. To improve the sensitivity
of the detection technique, the probe design was modified and the U-bent probe was fabricated by simple procedure. Further,
to overcome the problems for using UV light source in the fibre, the localized surface plasmon resonance of noble metal nanoparticles
at visible wavelength was exploited as a sensing medium for the biochemical reactions. Our systematic studies in this regard
presented in this communication may bring the excitement for developing the waterborne pathogen detection device for house-hold
as well as field applications. 相似文献
664.
665.
Dr. Yanbang Li Rohin Biswas William P. Kopcha Dr. Thierry Dubroca Dr. Laura Abella Yue Sun Ryan A. Crichton Dr. Christopher Rathnam Dr. Letao Yang Dr. Yao-Wen Yeh Dr. Krishnendu Kundu Dr. Antonio Rodríguez-Fortea Prof. Josep M. Poblet Prof. Ki-Bum Lee Prof. Stephen Hill Dr. Jianyuan Zhang 《Angewandte Chemie (International ed. in English)》2023,62(3):e202380362
666.
Dr. Yanbang Li Rohin Biswas William P. Kopcha Dr. Thierry Dubroca Dr. Laura Abella Yue Sun Ryan A. Crichton Dr. Christopher Rathnam Dr. Letao Yang Dr. Yao-Wen Yeh Dr. Krishnendu Kundu Dr. Antonio Rodríguez-Fortea Prof. Josep M. Poblet Prof. Ki-Bum Lee Prof. Stephen Hill Dr. Jianyuan Zhang 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2023,135(3):e202211704
Endohedral metallofullerenes (EMFs) are excellent carriers of rare-earth element (REE) ions in biomedical applications because they preclude the release of toxic metal ions. However, existing approaches to synthesize water-soluble EMF derivatives yield mixtures that inhibit precise drug design. Here we report the synthesis of metallobuckytrio (MBT), a three-buckyball system, as a modular platform to develop structurally defined water-soluble EMF derivatives with ligands by choice. Demonstrated with PEG ligands, the resulting water-soluble MBTs show superb biocompatibility. The Gd MBTs exhibit superior T1 relaxivity than typical Gd complexes, potentially superseding current clinical MRI contrast agents in both safety and efficiency. The Lu MBTs generated reactive oxygen species upon light irradiation, showing promise as photosensitizers. With their modular nature to incorporate other ligands, we anticipate the MBT platform to open new paths towards bio-specific REE drugs. 相似文献