Dredging is the excavation of material from a water environment. Possible reasons for dredging include improving existing water features; reshaping land and water features to alter drainage, navigability, and commercial use; constructing dams, dikes, and other controls for streams and shorelines; and recovering valuable mineral deposits or marine life having commercial value.
http://www.kedadredger.com/gold-minin.

Digital printing machine, also known as universal flatbed printer or flatbed printer, has broken through the difficulties of digital printing technology and realized the true one-shot printing, no plate-making, and full-color image completion at one time.
http://www.yssmdigitalprinter.com/dig.

Floor tiles are commonly made of ceramic or stone, although recent technological advances have resulted in rubber or glass tiles for floors as well. Ceramic tiles may be painted and glazed. Small mosaic tiles may be laid in various patterns. Floor tiles are typically set into mortar consisting of sand, cement and often a latex additive.
http://www.nokanitile.com/glazed-tile.

Coronavirus disease 2019 (COVID-19) is a contagious disease caused by a virus, the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). The first known case was identified in Wuhan, China, in December 2019. The disease has since spread worldwide, leading to the ongoing COVID-19 pandemic.
http://www.modaivd.com/all-poct-produ

A heat exchanger is a system used to transfer heat between two or more fluids. Heat exchangers are used in both cooling and heating processes. The fluids may be separated by a solid wall to prevent mixing or they may be in direct contact. They are widely used in space heating,
http://www.lxheattransfer.com/heat-ex