Photochemical smog.
* Describe in terms of the production of photochemical smog, what is meant by primary pollutants and secondary pollutants in the atmosphere, and list the main primary and secondary pollutants produced as a result of motor vehicles. Photochemical smogs are a mixture of smoke and fog derived from human activities. They take place in the troposphere, in the summer months. Photochemical smogs are highly oxidising. They contain a mixture of primary and secondary pollutants. Primary pollutants are released directly into the atmosphere by, for example, combustion of fuels in cars and power stations. Secondary pollutants are formed when primary pollutants undergo further reactions. An example of a secondary pollutant is Ozone. Ozone is a secondary pollutant because it is formed in chemical reactions that take place when the sun shines on a mixture of primary pollutants. The main primary and secondary pollutants released from motor vehicles are NOx (released from exhausts) of which contains mostly NO (95%) with only small amounts of NO2. Hydrocarbons are emitted from vehicle exhausts as unburnt fuel. Secondary pollutants due to these primary pollutants are O3, NO2, H2O2, PAN and partially oxidised VOCs HNO3. * Describe how primary pollutants are formed in the combustion of the fuel in a coal-fired power station. Coal-fired power stations are major sources of pollution. They have
Atmospheric Pollution.
Atmospheric Pollution Pollution is defined as the contamination of air, water or soil by materials that interfere with human health, the quality of life, or the natural functioning of ecosystems. Air pollution is the pollution of the atmosphere by emissions from industrial plants, incinerators, internal combustion engines and other sources. Pollutants can be classified as either primary or secondary. Primary pollutants are substances directly produced by a process, such as ash from a volcanic eruption or the carbon monoxide gas from a motor vehicle exhaust. Secondary pollutants are not emitted. Rather, they form in the air when primary pollutants react or interact. An important example of a secondary pollutant is ozone-one of the many secondary pollutants that make up photochemical smog. The motor vehicle engine emits many types of pollutants including nitrogen oxides (NOx), volatile organic compounds (VOCs), carbon monoxide (CO), carbon dioxide (CO2), particulates, sulphur dioxide (SO2) and lead. Listed below are the major air pollutants produced as a result of motor vehicles: Pollutant Sources Effects Sulphur Dioxide (SO2) A corrosive gas that cannot be seen or smelled at low levels but can have a "rotten egg" smell at high levels. Sulphur dioxide mostly comes from the burning of coal or oil in power plants. It also comes from factories that make chemicals, paper,
Atmospheric Pollution Caused By Coal-fired Power Stations And Motor Vehicle Engines.
Atmospheric Pollution Caused By Coal-fired Power Stations And Motor Vehicle Engines Photochemical smog contains a mixture of primary and secondary pollutants. Primary pollutants are released directly into the atmosphere whereas secondary pollutants undergo further reactions (1). The main primary and secondary pollutants in the atmosphere are shown in table 1 below. Table 1 Primary Pollutants NOx (NO + NO2), VOCs, CO Secondary Pollutants O3, NO2, H2O2, PAN, Partially oxidised VOCs, HNO3 The two main types of primary pollutants are oxides of nitrogen and VOC's (Volatile organic compounds) mostly hydrocarbons. Both are naturally present in the atmosphere but human activity heavily adds to this. Oxides of nitrogen are always produced when fossils fuels are burnt at a high temperature e.g. in a motor vehicle internal combustion engine. 95% of this is NO, which is a primary pollutant, with only small amounts being NO2 which is a secondary pollutant. Unburnt fuel in motor vehicles also releases hydrocarbons into the atmosphere. In a coal power station primary pollutants are formed by the burning of the fossil fuel coal. Burning coal at high temperature will produce oxides of nitrogen. Inside the coal are compounds of sulphur and nitrogen. These originate from the dead organisms that make up the coal. When the coal is burnt the Sulphur and Nitrogen is oxidised producing SOX
Nuclear power.
Nuclear power has changed the world. It has enabled the world to do many things that would have otherwise been impossible. There are two types of nuclear power Fission and Fusion. Fission occurs when a nucleus of an atom splits in two in order to gain greater stability. When the atom splits there is a huge amount of energy released. In this reaction there is a difference in mass between the reactants and their products. This energy can then be used to boil water, which can in turn be used to turn turbines and therefore make electricity. The other type is fusion. This is the kind of process that occurs in the sun. In this process 2 small atoms are forced together to form a bigger one. This process also releases large quantities of energy. Nuclear power has many advantages. It provides huge amounts of power of the amount of fuel that is used. One kilo of enriched uranium can produce as much power as 2 million kilos of coal. The electricity is produced without any of the problems that come from burning fossils fuels. There are no greenhouse gases produced and there is no ash to disposes of. There are however problems with this type of power production. The fuel is highly radioactive and this makes it toxic to humans. Radioactive emissions can cause many diseases including cancer. When a cell is bombarded by radioactive emissions then can mutate or die. Mutation can lead to
ERP and Organisational Change Management
ERP and Organisational Change Management Abstract Change has turn into an unending event and business process re-engineering has turn out to be a prerequisite for continued existence of organizations as we approach the 21st century. As participants in this ever-changing operational environment, we must be ground-breaking in managing change as it affects both our professional and persona lives. One of the innovative ways to manage change in the implementation of an enterprise resource planning (ERP) system is to adopt a comprehensive change management methodologies. The purpose of this paper is to describe how the change management is crucial to ERP implementation and to illustrate how the methodology can be used to implement successful change. INTRODUCTION Although most organizations have come to realize the benefits of using testing procedures and tools during an ERP implementation, many companies recognize the need for change-management support in their projects. IT organizations need solid support for a number of critical procedures that change-management practices provide, including version control to manage the large number of modifications made throughout a project, audit trails to keep well-documented records of those modifications, process and workflow control to define, coordinate, and control the steps within a project and issue tracking to keep all project
Environmental Problems.
Environmental Problems All cities experience environmental problems to a lesser or greater degree, usually causing great obstruction to the developers that attempt to improve the urban environment. The brown agenda that obstructs this includes these issues: * Waste * Dereliction * Air pollution * Noise * Water supply * Environmental health * Urban ecosystems Waste products and waste disposal * Solids from paper, packaging and toxic waste increase as the numbers and affluence increase * Liquid sewage and industrial waste both rise exponentially * Sewage control in Calcutta, India-during the monsoon season sewage can be seen pouring down the side of the street where the drains are insufficient to cope. * Contamination and health hazards from poor systems of disposal, e.g. rat infestation and waterborne diseases * An example of an MEDC problem of waste disposal is in the 'Bronx', south of New-York-rubbish continually clutters the streets, just like in the squatter settlements in Rio de Janeiro, Brazil. Solutions: Solutions to any problem are made more difficult by the lack of available resources and the sheer scale of the problems faced. * Improved public awareness-recycling etc, landfill sites, incineration plants and export to other areas (usually MEDC to LEDC) * Development of effective sewage systems and treatment plants including recycling of brown water
Evaluate The Impact Of Deforestation In Indonesia.
Evaluate The Impact Of Deforestation In Indonesia Indonesia is an island republic and the largest nation in South East Asia, comprising of more than 13,670 islands straddling the equator, 6,000 of which are inhabited. Its latitude is 5º N to 10º S and longitude 95ºE to 140ºE, and stretches across 5,150 km of ocean. Indonesia is home to approximately 10% of the world's remaining tropical forests. In December 1999 Indonesia had only 20 million hectares of forests left and the World Bank has said that Indonesian forests were reduced by an annual average of approximately 1.5 million hectares between 1985 and 1997. A number of factors cause this deforestation. These include the use of wood as fuel; the use of wood in the manufacture of paper; manufacture of other wood products; slash-and-burn farming; commercial farming; cattle ranching; infrastructure development; forest fires; population resettlement; insect pests and diseases; mining; pollution; and illegal logging. These in turn are all results of unsustainable levels of consumption; the effects of national debt; pressure for increased trade and development; poverty; patterns of land ownership; growing populations; and social relationships including gender relations. These underlying causes are often ignored in explanations of why forests are being destroyed rather than managed sustainably. It is more usual to blame
Evaluate the impact of deforestation in Indonesia.
Evaluate the impact of deforestation in Indonesia. Indonesia is the larges archipelago in the world with over 3000 islands including Borneo, Java and Sumatra. The islands lie on or close to the Equator. The climate is equatorial - hot and wet - and the typical vegetation is tropical rainforest giving Indonesia the name of the 'Amazon of south-east Asia'. Indonesia had 10% of the world's tropical rainforest but rapid deforestation is a major issue for the country. Deforestation is a global issue; it brings both advantages and disadvantages to the countries that have areas of rainforest and to those who depend on the rainforest products. Many are opposed to the development of rainforests because of the negative impact on the ecosystem and the indigenous people. This loss of rainforest and the associated fauna and flora is particularly significant in Indonesia because the country has the largest number of mammal species in the world, with over 20 000 plant species and 17% of the worlds birds. Several species of both flora and fauna are facing extinction and continued deforestation is likely to lead to reduced bio-diversity, reduced biomass and lower rates of net primary productivity. The impact f this is worsened because there are no replanting policies in place to replace the deforested areas. There are serious conflicts between indigenous people such as the Moi people and
Plate tectonics
Plate tectonics model The theory of which has revolutionized modern geology. A vast amount of scientific evidence supports the central theme of the theory that the earth's outer rock layer (lithosphere) is fractured into large pieces (plates) which move around the globe, carrying overlying oceans and continents with them. The theory has correctly predicted the distribution of earthquakes, volcanoes and mountain chains, greatly improving our understanding of geology. However, not all aspects of the theory are fully explained - the driving force behind plate motion is the subject of several competing hypotheses: . The Convection Cell Model: large convection cells in the earth's partially molten mantle exert a drag on the overlying plates, carrying them along like objects on a giant conveyor belt. Ridge push" and "slab pull" are both ways that gravity can act to keep a plate in motion. Note that arrows on convection cells and overlying plate are going in the same direction. 2. The Push-Pull Model: the creation of new oceanic plate at spreading centers pushes the plates away on either side and, at the same time, colder, denser plate material sinks at subduction zones pulling the plates along behind them. The electromagnetic field applies both pushes and pulls to bodies in the field. This is accomplished via photons and photon "holes" in the field traveling both forward and
Plate Tectonics
Jai Mehta 11AY ) 2) a) Plates "float" or move very slowly (a few mm per year) on the molten material of the mantle. Convection currents in the mantle cause this movement. b) Plates meet at plate boundaries or margins. c) Plates that move apart are known as diverging and are constructive, as new features are formed e.g. submarine volcanoes in the Mid Atlantic plate margin. d) Plates that move towards each other are converging and destructive - Fold Mountains, earthquakes, and volcanoes are common. e) Plates which move sideways against each other are conservative margins - material isn't gained or lost, volcanoes are rare and earthquakes are common e.g. San Andreas Fault. f) Pangaea was a single landmass; made up of all the present continents, believed to have existed between 300 and 200 million years ago the rest of the Earth was covered by the Panthalassa Ocean. Pangaea split into two landmasses Laurasia in the north and Gondwanaland in the south, which subsequently broke up into several continents. These then moved slowly to their present positions, due to plate tectonics. Jai Mehta 11AY 3) A Map Showing The Location Of The Worlds Plate Boundaries. Jai Mehta 11AY 4) Volcanoes can be found where Earthquakes are found, at plate margins/ boundaries. The map below shows a good example of this; you can see where the pacific plate meets surrounding plates and many
