Nano materials not applied in

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Nanomaterials are extensively used in the manufacturing of scratch-proof glasses, electronic devices, and self-cleaning materials (such as titanium dioxide nanoparticles). Conventional water treatment relies on traditional physical and chemical processes like coagulation, flocculation, sedimentation, and sand filtration, which do not involve the use of nanomaterials. Advanced water treatment may use nanomaterials, but conventional methods do not. Answer: Conventional water treatment