Science and Materials for construction and the built Enviroment Essay

Science and Materials for construction and the built Enviroment - Essay Example Its strength and durability make it a great choice for structures exposed to high amounts of stress, such as weather, heat, large amounts of applied force and constant usage† (LaRoche, 1999). Modifying the chemical structure of the alloy permits steel to have enhanced and multiple uses. It has many other benefits apart from construction of roads and buildings, such as building of ships, cars and every other means of transport. It can literally be said that steel is unconstrained in its possible benefits. It is a major element in the construction of home appliances, automobiles, and shipping containers and various other machines. 2. Copper It is a thin wired metal with a high-level of thermal and electrical conductivity. It is used as a conductor of electricity and heat, a building material, and as a constituent element in various metal mixtures. The low stiffness of copper describes its huge electrical conductivity and, therefore, also high thermal conductivity, which is the se cond most important feature among pure metals at room temperature. This is since the resistivity to electron transport in metals at room temperature frequently derives from dispersion of electrons in thermal atmosphere of the network, which is comparatively nullified in case of a soft metal. â€Å"The maximum permissible current density of copper in open air is approximately 3.1?106 A/m2 of cross-sectional area, above which it begins to heat excessively† (Phillip, 2006). Electrical conductivity is a vital property in electrical wiring technique. Copper has the maximum electrical conductivity ranking among all non-precious metals. A distinctive combination of high strength and high ductility enables copper to be perfect for wiring systems. In electrical systems, high thermal conductivity is necessary for dispersing waste heat, mainly at terminations and links. It is also necessary for dropping energy consumption appropriate to the creation of waste heat. 2. Aluminum Aluminum i s a metal similar to copper, steel, brass, zinc, lead and titanium. It can be dissolved, radiated, created and developed like the aforementioned metals and it also conducts electric current. The strength and durability of an aluminum mixture differs generally, not only accordingly of the elements of the specific mixture, but also as a result of heat treatments and production procedure. Aluminum is a tremendous heat and electricity conductor and in association to its weight, it is approximately twice as high-quality a conductor as copper. This has led to aluminum being the main generally applied material in main power transmission approach. 3. Timber Timber is light, strong and reliable form and timber construction is easy and secure than steel or concrete construction material. Good featuring, coating and protection ensure that goods produced from timber are durable. Though many buildings become outdated and are destroyed long before the ending of their usual lives, timber construct ion properly planned and preserved could have an imprecise life. The input to extended life provides security from weather, insects and decomposers, with the help of fixed design featuring, surface coating systems, collection of durable types, and stabilized treatment procedures. The flexibility and strength property is â€Å"due to the (abundance) of interlocked fibers to provide strength. The direction and structure of the cells also effects the strength of the timber, straight grained

Social Change Essay Example | Topics and Well Written Essays - 750 words - 3

Social Change - Essay Example Supply and demand for dangerous drugs is international and global. An important source of world opium, for example, is Afghanistan and the United Nations Office on Drugs and Crime is anticipating that cultivation of opium in the Northern and North-Eastern regions of Afghanistan will likely increase â€Å"strongly† this 2011. For Cocaine, an important source is Columbia and the cocaine goes through several routes by various means of transportation and through several countries before going to Europe and, of course, the United States. Some of the transnational routes for cocaine are shown in Figure 1. Drug use is not only a problem of law enforcement. Several studies confirm that it is a social problem. Several studies of the US National Institute on Drug Abuse in 1980, for example, pointed out that the drug problem arose because of social factors. On the other hand, a 1995 study of the United Nations International Drug Program indicated that the drug problem will have social consequences. Addressing the use of illegal drugs and narcotics require more than a cloak-and-dagger and police work approaches as it is a social problem in the first place. There is a need to work on both the supply and demand sides of the social problem. On the supply side, there is a need for at least five initiatives. First, there is a need to strengthen international cooperation and sharing of intelligence towards exposing and destroying the international networks engaged in illegal drugs and narcotics. This means that current efforts on the sharing intelligence must be supported. Most likely, the world has the technological capability to identify the plantations that are likely being used as the raw materials for producing drugs. This is one important piece of intelligence that must be shared worldwide. Volumes of drug transports require large ships, planes, and the like for international transport. In some of the