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Cement, powdered hydraulic inorganic cementing material. After mixing with water, the slurry can be hardened in air or in water, and can firmly bond sand, stone and other materials together. The mixture of early lime and volcanic ash and modern lime and volcanic cement, which is used to bond the concrete made of crushed stone, not only has higher strength after hardening, but also can resist the erosion of fresh water or salt water.

Water industry refers to the industrial chain composed of raw water, water supply, water saving, drainage, sewage treatment and water resource recycling. Water industry is one of the most important urban basic service industries in China and even in all countries and regions in the world, and daily production and life are inseparable from urban water supply.

Hvac is an integral part of the building, including: heating, ventilation, air conditioning three aspects. Engaged in the field of building environment control, building energy conservation and intelligent technology of building facilities, with air-conditioning, heating, ventilation, building water supply and drainage, gas supply and other public facilities system, building heat supply system and building energy conservation design, construction, commissioning, operation management capabilities and building automation department.