Electricity can be defined as the phenomenon of moving or stationary electrons and protons. Although electricity has always been present on our planet in countless forms, it remained little more than an intellectual curiosity until 1600, when an English scientist by the name of William Gilbert made a careful study of electricity and magnetism, distinguishing the lodestone effect from static electricity produced by rubbing amber. [1]A lodestone is a naturally occurring magnetized...
Despite persistently high oil prices, global energy demand will grow by 50 percent over the next two decades with continued heavy reliance on environmentally troublesome fossil fuels, especially coal and oil, the UN predicted. The report forecast the steepest increases in China and other emerging economies where energy demand is expected to be 85 percent greater in 2030 than it is today. One of the biggest challenges of our time is the need for energy. Energy consumption is steadily increasing,...
During the past decades, some developed countries such as UK has experienced serious environmental pollution along with the development of industry. And this condition still exists in many developing countries. The development of industry has strongly facilitated our lives. But at the same time, it also has brought a lot of risks to the environment. Water pollution, air pollution and land pollution are not only threatening human's health, but also the existence of the earth. Environmental...
Issues of energy conservation in the transport sector are becoming increasingly relevant in the light of the annual growth of energy consumption, degree of negative impact on the environment, and emissions of harmful substances. In terms of energy consumption growth in 2000-2007, the transport sector yielded only to the industrial one. Energy consumption in the transport sector increased in 2000-2007 by 43%, which made 31,5% of final energy consumption (Energy policy, 2009). The main reason for...
A volcano is an opening, or rupture, in a planets surface or crust, which allows hot magma, volcanic ash and gases to escape from below the surface. Volcanoes are generally found where tectonic plates are diverging or converging. A mid-oceanic ridge, for example the Mid-Atlantic Ridge, has examples of volcanoes caused by divergent tectonic plates pulling apart; the Pacific Ring of Fire has examples of volcanoes caused by convergent tectonic plates coming together. By contrast, volcanoes are...
Climate change is one of the main debate topics in our popular Medias. Evidence shows that we are experiencing a very fast approaching climate change due to global warming. A climate change would have disturbing and disastrous effects on the human population, plant and animal life. Life in a new climate would be inherently different if such a change were continues to happen. Do humans contribute global warming? There is a general agreement between scientists that earth climate is being...
1.0 General: Mortar mix is a combination of cement and sand that is used to hold together construction type blocks. On adding water it becomes a workable paste that sets hard. It is used with materials like bricks and stones to make walkways and walls. Mortar was originally made of mud or clay. There is evidence of the use of mortar in cultures around the world. Iranian and Babylonian structures used mortar from about 2900 BC on. The earliest Egyptian pyramids used the mud or clay combination,...
The terms sand dams , subsurface dams and sometimes sand weirs are often used interchangeably to refer to the same, or different, kinds of structure. In a sand dam, the dam wall protrudes above the surface of the sand, while in a subsurface dam, the dam wall is level with the sand surface. It should be noted that these structures are feasible only in certain areas. The type of soil in an area is important because it determines the types of sediment deposited in a dam and consequently its water...
Water is humankind's most basic necessity. Approximately one in eight people are without access to clean, safe drinking water (JMP 2008:56). The water crisis of the global South--Buenos Aires, Jakarta and Cebu in particular--is a complex, locally defined and contentious issue; debates about whether water is a public human right or a privately owned consumer commodity are taking priority in development discourse on the international stage. Inherent to this issue is a historic power relationship...
The irreversible loss of the earth's diverse biological resources is given major importance today. The living resources are primarily threatened by habitat degradation and loss, habitat fragmentation, overexploitation, and species invasions (Groom & Carroll, 2006; Mittermeier & Bowles, 1993) which most experts believed we are now confronting the sixth major extinction in history. The different natural resources or biodiversity, as defined by the Convention on Biological Diversity, is...