A ceramic membrane includes an alumina (Al.sub.2O.sub.3) layer; and a polyamide nanocomposite layer at least partially covering a surface of the alumina layer. The polyamide nanocomposite layer contains polyamide-functionalized silicon carbide (SiC) nanoparticles having an average particle size of 0.1 to 1 micrometer (m), an amine-functionalized SiC moiety, an acyl aryl moiety, and a piperazine moiety. The amine-functionalized SiC moiety contains a SiC core and an amine functionalized silicon dioxide (SiO.sub.2) shell covering the SiC core. The amine-functionalized SiC moiety is covalently bonded to the piperazine moiety via the acyl aryl moiety; and the amine functionalized SiO.sub.2 shell contains at least one amino group containing structural unit that is covalently bonded to the SiO.sub.2 shell.

The present teachings describe photocatalytic composite materials that are useful for remediation of bodies of water such as lakes, ponds, wetlands and rice fields, as well as remediation of sediment under the water.

An underground stormwater management system comprising a first chamber, a second chamber, and at least one filter member. The first chamber has a floor, a plurality of walls, and an inlet. The second chamber has a floor and a plurality of walls. The filter member comprises a corrugated member and a filter fabric. The corrugated member has through holes that permit stormwater to flow through the corrugated member. The filter fabric covers at least a portion of the corrugated member and filters silt or particulate matter from stormwater before the stormwater flows through the through holes. At least one of the plurality of first chamber walls has a plurality of first openings that permit stormwater to flow from the first chamber to the second chamber. Stormwater flowing from the first chamber to the second chamber flows through the filter member before flowing through the plurality of first openings.

A method of water treatment includes treating a mixture of water and oil with a membrane that includes a polyimide formed by polycondensation between 4,4-(4,4-isopropylidenediphenoxy)bis-(phthalic anhydride) (BPADA) and 2,4,6-trimethyl-m-phenylenediamine (TrMPD). The polyimide does not include fluorine. The polyimide is in the form of fibers having an average diameter of 0.5 micrometers (m) to 5.0 m, and the fibers are bead-free and are formed by electrospinning to form a membrane having pores with an average size of 2 m to 10 m.

A cleaning robot (1000), comprising a water-surface body (100) and an underwater body (200) detachably connected to the water-surface body (100). The water-surface body (100) is configured for floating on the surface of a working water area. The underwater body (200) is configured for cleaning at least one of the working water area and the wall surface of a pool. The water-surface body (100) comprises a functional module (2), which comprises at least one of a power supply module (21), a collection module (22), a driving module (23), a communication module (24), a sensor module (25), an alert module (26), a water-quality detection module (27) or a water-quality improvement module (280).