  Crushed stone, for example, has a density of 100 pounds per cubic foot (lb/ft3), which is 1600 kilograms per cubic meter (kg/m3), which is 1.6 metric tons per cubic meter. Packed earth is about 95 lb/ft3, or 1520 kg/m3.
Harvard Business Review. Harvard Business Review. The Harvard Business Review (HBR) is a general management magazine published by Harvard Business Publishing, a wholly owned subsidiary of Harvard University. It is published 6 times a year and is headquartered in Brighton, Massachusetts.
The unique properties attributed to HNBR have resulted in wide adoption of HNBR in automotive, industrial, and assorted, performance-demanding applications. On a volume basis, the automotive market is the largest consumer, using HNBR for a host of dynamic and static seals, hoses, and belts.HNBR has also been widely employed in industrial sealing for oil field exploration and processing, as well as rolls for steel and paper mills.NBR is widely known for its physical strength and retention of properties after long-term exposure to heat, oil, and chemicals. Depending on filler selection and loading, HNBR compounds typically have tensile strengths of 20 - 31 MPa when measured at 23Â°C.