Archive for November 2014

Molding Plastics Properties

Auger – a piece of equipment, conducting molding plastics. He is one of the key elements to ensure the operation of such apparatus. Its function in the molding of plastic is really important: it takes the source material melts it and submits the form. Screw on its design features must exactly match the characteristics of a substance used in injection molding. Its geometry, the presence of additional elements and other parameters are determined by the properties of polymers, as the temperature of transition from one state to another (melting and solidification), temperature stability and so on.

What is particularly important in molding compounds plastic? Firstly, this temperature regime, where the polymer can be processed, ie, to cast plastic. The wider the figure, the easier it runs the process of working with substance. In particular, if the polymer has range of more than 50 degrees, the plastic molding is uncomplicated. If this parameter is below 30 degrees, the polymer is recognized trudnopererabatyvaemym. If in the plastic molding material is heated more allowable limit, then decomposes (or thermal destruction). It loses its original properties and can not be used in molding plastics.

Therefore, it is important that in injection molding equipment was accurate setting, especially if you use materials with low processability. In such cases, the auger is equipped with special channels, that fed cooling fluid. With their help you can provide and additional heating if necessary. In injection molding is also very important, exactly how the polymer changes its physical state – gradually or abruptly. This is reflected in the design of the screw, since such differences feed substance and its mastication occur in different ways. Smooth transition is characteristic of polysulfone, polycarbonate, polystyrene and its copolymers. The abrupt transition – a measure of the substances used in molding plastic, such as polyamides, polypropylene and other polymers.

Coral Reefs And Diseases

Studying coral reefs, the scientists found that the number of different diseases of corals, the smaller the greater diversity of fish living near these reefs. Reefs are found in protected waters have a healthier ecosystem, than reefs where fishing is allowed. In the course of his research team found only one species of fish, which has a negative impact on the coral – it butterfly fish, which feed on hard corals and only occasionally caught by fishermen. Study by researchers in handy – for now, coral reefs are rapidly disappearing from the face of the earth. Corals are dying because of pollution, global warming, species extinction animals needed to sustain the existence of the reef community.

In addition, the major cause of death of coral reefs are a variety of coral diseases. What exactly causes the spread of diseases in Reef – until recently for scientists remained a mystery. Polluting air particles can 'travel' from one continent to American scientists have found that air-pollutant emissions have a negative impact on the ecology of another country far away from their 'homeland'. Harmful air particles that pollute environment, can 'travel' across the oceans from different continents – from Asia to America and from America to Europe. Although Air quality in one country are almost always determined by the dominant number of local industrial and domestic emissions, a significant impact on the environment can render and external sources contamination came from other continents. Thus, the global environment has no national boundaries. That is, greenhouse gas emissions in one country can adversely affect human health and ecosystems, and other States, despite the considerable distances.