Boiling is the oldest method of household water treatment, and today it's practiced by an estimated 600 million people around the world Boiling of Water Heat, in fact, kills through different mechanisms heat impacts enzymes and causes them to denature and become non functional. It can affect the proteins that make up cells and cause them to unfold and change their shape. And also within a cell it can increase the pressure which damages cells. We'll look at two broad classes of heat treatment; boiling and pasteurization. To understand how heat disinfection works we have to first think a little bit about temperature and pressure, and recognize that pressure affects the boiling point. If the pressure is higher, then the boiling point can be higher. And in fact, this is how an autoclave works with steam sterilization and high pressure about one bar above atmospheric pressure and that allows water to reach 121 degrees Celsius. And if it's kept there for 15 minutes under steam i...
The first assessment from the Intergovernmental Panel for Climate Change in eight years will sound the alarm on soaring temperatures and other effects of unchecked carbon pollution A woman gets a hand from a friend as they walk in flooded streets as the Neuse River begins to flood its banks during Hurricane Florence September 13, 2018 in New Bern, North Carolina. Credit: Chip Somodevilla Getty Images The United Nations is poised to release the most confident and comprehensive assessment yet of global warming, including detailed estimates of how continued greenhouse-gas emissions will increase Earth’s sea levels and drive extreme weather in the coming years. Compiled by more than 200 scientists and approved by government representatives from 195 countries, the report from the Intergovernmental Panel on Climate Change (IPCC) will leave little doubt that humans are altering the way the planet functions — and that things will get much worse if governments do not take drastic action, say cl...