Search

...system within 2 weeks. This is sterile immunity: the virus cannot be obtained from the patient after recovery from the disease. Figure 2 shows the typical time course of an acute flu infection. [Time course of flu infection.] Figure 2 Time course of a typical flu infection. Production of the virus (purple bar) starts early after infection and is maximal within two days....

...systems should allow the cavity to be filled rapidly. Vents and risers must be located in such a way that the unfilled portion of the casting cavity is at atmospheric pressure, to allow the gases formed in the initial stages to escape to atmosphere. Knock-out is easy, since removal of the vacuum allows the sand to flow out of the box. When casting cast iron, or other...

...system contains the workpiece on all sides, which eliminates the tensile stresses developed in conventional hot forging. The high rate of working leads to heat generation to compensate for radiation losses, so that multiple passes can be used to produce a forging in a single heat. This leads to substantial energy and labour savings compared with conventional forging....

...systems in action. India’s busiest city, Mumbai, is right at the heart of the world’s busiest railway. Mumbai is situated on a peninsula of land on the west coast of India, surrounded by the Indian Ocean. Its most important transport hub, the historic Chhatrapati Shivaji Terminus, opened in 1887 when India was still part of the British Empire. The station was built...