Archive for August 2011
Melamine is a chemical compound comprised of carbon, hydrogen and nitrogen. It is a white substance that was first created by a German chemist called Justus von Liebig in 1834. It is harmful if swallowed or inhaled and can cause damage to the reproductive system and kidneys. In 2008 many brands of Chinese infant formulas were found to contain high levels of melamine, which led to 50,000 hospitalizations and 6 infant deaths from kidney failure. It is also a known carcinogen and can even cause death in large amounts. However, despite these drawbacks melamine has many uses in a variety of industries.
Wind power has been harnessed by humans for a variety of purposes throughout history. Some of these uses include sailing ships, windmills and, more recently, power generation. Today, it is used to generate approximately 200 gigawatts of power throughout the world. Wind turbines are commonly used throughout Europe, but China currently has the world’s highest wind power capacity of any country. There have been at least 9 accidents relating directly to power generation from wind, but it is still considered to be one of the safest and environmentally friendly methods of power generation. You may have seen the large wind turbines that are used to generate this power, but have you ever wondered how they work?
Our Sun provides us with all the warmth and light we need. It is essential for life and, if it could be harnessed, produces enough energy to power the whole planet. The Earth is the only planet in the solar system that supports life and part of the reason for this is the distance of the Sun from the Earth. If we were too close to the sun the Earth would become too hot for life and if we were further away from the sun the Earth would be too cold.
Selenium is a chemical element with the chemical symbol Se. It has the atomic number of 34 and an atomic mass of 78.96. Most selenium is produced as a by-product of refining other elements or during the production of sulfuric acid. It is solid at room temperature and can exist in many forms. The most common of these forms is gray selenium, but red selenium is also quite common. It is toxic in high doses, but, in the correct doses, it is an essential nutrient for animals. It also has many other uses including in glass production. If you have ever wondered who discovered this important element, continue reading to find out.
Bifocal glasses are designed with 2 different lenses in the one pair of glasses. They are generally used by people who have diminished eyesight and also require correction for nearsightedness. This allows the wearer to see clearly at all times, while also providing focus for tasks such as reading. Traditionally they were made of two separate lenses, but today a small section for reading is molded into the main lens.