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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In heavy metal producing industries such as electroplating, metal-finishing, steels, chemical manufacturing, leather tanning, the handling of effluent has always been the main concern. Improper treatment to the wastewater before it is drained out into rivers or oceans will cause a great pollution an.....
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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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At present time techniques in preparing advanced ceramic materials with high electrical conductivity and magnetic susceptibility are rare. This new invention relates to hyperbranched organometallic polymers, which are useful as precursors to certain ceramic materials, processes for the preparation o.....
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Bacillus subtilis has been widely used for extracellular production of native and homologous proteins. Based on the use of a synthetic expression/secretion cassette, a new bacterial expression system is developed and may be applied to produce heterologous proteins efficiently as secreted products. .....
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