It is very difficult to shield low frequency sound waves. This is mainly because in order to cause wave scattering or reflection, the usual wisdom is that the size of the scatterers must be on the order of the wavelength. Since low frequency sound has long wavelength, it follows that the shielding m.....
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The present invention introduces a novel process of preparing branched polymers and branched organic materials containing triaroylbenzene moieties as one structural unit by cyclotrimerization. Among conventional methods for synthesis of hyperbranched polymers, it is found that degree of branching is.....
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Zeolites are microporous crystalline aluminosilicate molecular sieve that have pore sizes ranging from about 0.3 to 1 mm. Due to their uniform, molecular-sized pores, they can separate molecules based on their size, shape and polarity. They can therefore act as ''molecular sieves''. Membranes made o.....
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The present invention provides a bone treatment device (1), which allows for reinforced security at the bone interface and/or for delivery of a bone treatment material (30) into a bone portion. The bone treatment device (1) has shaft member (10) with first and second end portions (14, 16). A deliver.....
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The operational frequency of existing magnetoelectric materials having metallic or ceramic magnetostrictive materials and ceramic piezoelectric materials may be limited to a few kilohertz due to the presence of eddy-current losses in the metallic magnetostrictive phase. Further, these materials may .....
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