Renewable Energy Essay Example for Free

Renewable Energy Essay The possible downsides associated with different types of renewable energy resources are briefly listed below. Hydroelectric dam Located in remote hilly regions mostly prone to earth quakes Requires construction of large dams in potentially seismic zones Seasonality in power output as water flow is more in rainy season Nuclear Power Plants Accident if occur will cause lot of damage Radioactivity exposure to the personnel Radioactive waste disposal continues to be an unsolved issue Nuclear proliferation fear Solar Power Technology is yet to mature in terms of affordable and efficient solar panels Conversion efficiency is low Scalability is an issue Depends on sky condition Cannot produce electricity in night so storage device is required Green power refers to renewable energy resources which do not adversely affect ecological balance. Some examples are hydroelectric power, wind power, solar power, biomass etc. Advantages and disadvantages are listed below. Green Power Source Advantage Disadvantage Wind energy Free, clean Reliability is a big question mark Solar Energy Free, Clean, Plentiful Low conversion efficiency Hydroelectric Clean, free Located in remote hilly regions Today, the world is interested in renewable energy resources because the fossil fuels are limited in reserve and will deplete completely one day. Also, exploitation of the fossil fuels is leading to ecological imbalances and causing green house effect leading to global warming, which is a very serious issue, globally. The only answer to these problems is to go for renewable energy resources. Therefore, the world is so much interested in decreasing energy production from fossil fuel and increasing the same from renewable energy resources.

Francis Parkman :: essays research papers fc

Many people regarded nature and the world with their eyes only. However, some perceived the world through all their senses. They stopped and listened to what appeared before them, and then they experienced their surroundings. One person who looked beyond his first impression was Francis Parkman. Parkman’s love for history and nature drove him to overcome his physical weaknesses. He pursued his passion with the diligence of a soldier and brought a different perspective to nineteenth century history. Francis Parkman traveled across North America and obtained firsthand experiences about nature, hardships, and the unknown. He developed his quest for knowledge as a child on the Hall Farm in Quincy, Massachusetts. Parkman battled the degenerating loss of his health, the loss of only son, and the loss of his wife. He compiled his wisdom in letters, journals, articles, and books; and Parkman left a legacy unmatched by historians of his time. On September 16, 1823, the union of Reverend Francis Parkman and Caroline Hall Parkman produced a son, Francis Parkman, Jr. The Reverend and Mrs. Parkman, his second wife, resided in Somerset Place, Boston, and the family tree consisted of ministers, merchants, philanthropists, and brave Indian fighters. The Parkman family spent winters in Boston and summers at the Hall farm in Quincy, Massachusetts. The farm in Quincy provided Parkman with a vast area of rocks and forestry to explore, since it happened to be located adjacent to the Five Mile Woods, later renamed the Middlesex Fells. He encountered many illnesses in Boston, and his parents decided to leave him in his grandparents’ care on the farm. On the farm he collected rocks, trapped animals, shot arrows at birds, and conducted experiments. He wrote about himself and his experiments in the third person just as his peer, Henry Adams, regularly did. Parkman returned home to his parents at age thirteen to begin private school ing. Parkman attended Gideon Thayer’s famous private school, Chauncey Hall, in order to prepare for college at Harvard. He entered Harvard in August 1940, and he excelled academically, physically, and socially. In addition to his regular studies, Parkman joined several school clubs and helped found another one. In July 19, 1841, during summer break from Harvard, he and Daniel Denison Slade took a trip to explore the White Mountains located in New Hampshire and Maine. Parkman, aware of an avalanche that killed nine in 1826, eagerly climbed the unstable flume close to Notch House.

Ediment grain size and mineralogy distribution Essay

The study was done in the Mpenjati estuary. It was found more briefly if sediment grain size and mineralogy distribution change across a beach profile changes and how it change. 4 zoneS of a beach profile were sampled. Quartz is the most stable sediment composition in the surface of the earth, compared to heavy minerals and feldspar (Marshak, 2008). INTRODUCTION The aim of the study was to find out how does the sediment grain size and mineralogy distribution change across a beach profile. Mineral is a homogenous, naturally occurring solid inorganic substance with a definable chemical composition (Marshak, 2005). The impacts of the depositional environment, transport and climate on the morphology of minerals oceans are the focus of discussion during the present study of grain morphology (Shaffer,2006). It goes without saying that morphology and texture as well as the intergrowths among ocean minerals are also of utmost importance for the and industrial use of placer minerals (Pipkin, 2007) and by this oceans profiles must not be protected from pollution and disasters. The Mpenjati Estuary has been subjected to extensive sand and stone mining for approximately 40 years and the mining operations affected sediment patterns (matthias et al,2012). Although geologists tend to classify estuaries according to their geomorphology, physiography, sedimentation or tidal patterns but an estuary is an enclosed coastal body of water which is periodically or permanently open to the sea (Whitfield, 2010). The study was done by the University Of KwaZulu-Natal students of BIOL 231 (Marine environments) together with their demonstrators and Lecturer. The study was done in the Mpenjati estuary on the third of August 2013 which is the winter season while the estuary was closed at the mouth. The Mpenjati estuary is an open/ closed estuary located at 30 Í ¦ 58’15† and approximately 165km southwest of Durban Kwazulu-Natal south coast FIGURE 1: Locality map showing Mpenjati estuary (Whitfied, 2003) FIGURE 2: beach profile showing different zones (Schwarts, 2008) MATERIALS AND METHODS Sampling was done when mouth of the estuary was closed. Four different zones of the beach profile were sampled which is Swash zone 1 which was closer to the sea followed by swash zone 2, and back beach 1 which is closer to the estuary followed by back beach 2. In each zone 2 clear plastic bags were filled with half way with sand using our own hands and were sealed with sell tape for later processing at the Lab. The plastic bags which had sand were named according to their zones collected from. The collected sediments were then taken to the soil laboratory at the Geological science Department (UKZN) for drying for 3 days. In the laboratory the sieve trays ware weighed using balanced scales after weighing. Sand which came out from drying was crushed and grinded and stirred on to the bowls using a thick pin as if cooking. Sieve trays were stacked together and then placed in a sieve machine where the dry grinded sand was stirred more on the machine for 2 minutes. After the 2 minutes the sand or sediments were poured on to the sieve trays which have different sizes of open holes measured in  µM, the top sieve tray had the biggest porosity and the bottom one had the smallest and was consisting of finest sand. When sieving was done the sieve trays were weighed again in order to obtain the mass of the sediment grains collected on the estuary. From the masses of the dishes the value of Phi (Ø) was calculated:Phi (Ø) = -log2 (d) d = Mass of a sieve /1000 The calculated phi was then used as a dependent variable in plotting graphs for distribution and the cumulative frequency that are displayed in the results. Phi ranged from -1 – 3.47 then the base.This was done for each zone I the four zones which were sampled. A small portion of sediments was collected In each zone of sampling was then placed into a petri dish and was examined by a light microscope for analyzing different types of minerals which were in each set of sediment zone by looking at their grain size, texture, and the mineral composition of the sand. This was done for each zone. The field observations are also confirmed by the graphs that in figure 4 the mass content, sediment mean size goes from high to low from swash zone 1 to back beach 1 showing that as one goes closer to the sea the sediment grain size of the sand and mass increases. Table 1 tells us that the back beach has more quarts e.g The back beach has the highest quarts. DISCUSSION It has been found out from figure 2 that the beach profile is divided into different zones, 4 zones were sampled at the mpenjati estuary namely swash zone 1, swash zone 2, back beach 1 and back beach 2. It was also found in figure 3, figure 4 and table 1 that the 4 zones have different mineralogical distributions and grain size. It was found that the soil colour and texture of the sand changed from zone to zone. The sand was damp with and had shells, little fragments, oysters afflicted by waves and washed to the sand by wave deposit. The ripples indicated wind direction and the wavelength of ripple was 6.5 cm. The deeper side of the ripples is gentle and shorter on the side of the ripples; this is due to north east blow of the wind (Marshak, 2005)) The swash zone is a zone of constant deposition from the beach characterised by moderately to poorly sorted sediments as sediments of first deposition are sub angular with a grain shape of low sphericity compared to other zones in the beac h (table 1). The long shore drift which passes across the beach water body creating wave action energy is insufficient to carry these types of sediments (Shaffer, 2006). The reason why small sediments in size are mostly found at the back beach (figure 3 and 4) is because the wave action slows down its energy in the swash zone so only small sediments in size can be carried towards the back beach leading to well sorted sediments with mature texture as high transportation of  sediments leads to re-deposition and re-transportation (Pipkin, 2007)). Closer to the sea were larger stones and burrows (figure 4) swash zone 1 had the highest mass content followed by swash zone 2 and the reason for this is because closer to the sea there is more wind action (Shaffer, 2006). Crabs adapted to the environment with burrows. Quartz is the most stable sediment composition in the surface of the earth, compared to heavy minerals and feldspar (Marshak, 2008). Quartz and feldspar are dominant in all beach zones (Table 1) this is because they are primary rock minerals, they are found in parent rock e.g. granite which contains these two minerals (Schwarts, 2005). Since so il is the deposited by the chemical weathering of rocks, the minerals also are as a result that deposition. Feldspar makes about 60% of the earth’s crust (Marshak, 2005). Mineral sands contain suites of minerals with high specific gravity known as ‘heavy minerals’. They were found mostly on the back beach 2 (Table 1) and the swash zone 2 because the wind current was not strong enough to transport them away. Those that are found on the back beach 2 are probably deposited by the river inflow and that on swash zone 2 is deposited by the ocean current and cannot be transported further because they are resistant to wave action (Pipkin, 2001). The swash zone was found to have more shells (Table 1) and some broken up and there were smooth, dishaped stones (cables) because of wave action on tide and also pedals. Lithic fragments were found mostly the back beach (Table 1) and only one on swash zone 1 because they are light and easily transported by wave and wind action. In conclusion as the profile is divided into zones it was found that mineralogical distribution and grain size change across the zones of a beach profile. As one go closer to the sea the gran size becomes larger and there was found to be more mineralogical diversity to zones closer to th e sea compare to zones closer to the estuary. Heavy minerals were found in zones closer to the sea and light minerals were found to zones far from the sea, this is all due to processes like wind and wave action. REFERENCES Marshak S.S., (2005). Earth: Portrait of the planet 2nd eds. W.W. Norton & Company, Incl., New York, London Marshak S.S, (2008). Earth: Portrait of the planet 3rd eds. W.W. Norton & Company, Incl., New York, London Matthias (2012) et al, KOTLIK School, AK 9960. P.O BOX 20129, 8 JUNE 2012, The Nushagak Estuary: Its Salmon resource, Potential Threat and proposed management plan. Pipkin B.W., et.al, 2001. Labaratory exercise in Oceanography, 3rd edition. USA Ron Uken 2011, UKZN WESTVILLE CAMPUS BIOL 231 PRACTICAL MANUAL (GEOLOGICAL COMPONENT) Schwartz M.L., 2005. Encyclopedia of coastal Sciences. Published by springer 16 June 2005 Shaffer,R., (2006). The Time of Sands: Quartz-rich Sand Deposits as a renewable Resource. Electronic Green Journal, 1(24):1-35 Whitfield A.K, J.L.B Smith institute of Ichyology, Private Bag 1015 Grahamstown, 6140, South Africa published online: 08 November 2010, 18: 1-2, 89-103, DOL Whitfield A.K Maps and Locations of South African Estuaries Index, Generated by resource quality service 2003-08-08, 14:25:28, S.A INDEX for aquatic Biodiversity.

Latin Imperative Verbs

Normally, the imperative mood is used for direct commands (orders): DormiGo to sleep! English rearranges the word order of the declarative sentence, if its necessary, and replaces the period with an exclamation point. The Latin imperative is formed by removing the -re ending of the present infinitive: dormire without the -re is dormi. When ordering two or more people, add -te to the singular imperative. When telling more than one person to go to sleep, you say: DormiteSleep! For the plural imperative of 3rd conjugation verbs, the e before the dropped re is changed to an i. Thus, the plural imperative of mittere to send is: mittiteSend! but the singular imperative is: mitteSend! There are some irregular or irregular-seeming imperatives, especially in the case of irregular verbs. The imperative of ferre to carry is ferre minus the -re ending, as predicted: ferCarry! in the singular and FerteCarry! in the plural. The imperative of the verb nolo is used to form negative commands. To say dont in Latin, you ordinarily use the imperative of nolo with the infinitive of the other verb.Noli me tangere.Dont touch me! Present Imperative of Nolo Singular: noliPlural: nolite More On the Negative Imperative You can also use other constructions. For instance, for the prohibitive imperative dont hurry you would say ne festina. More Imperatives There are also less common passive and future imperatives. For the verb to love amare, the passive imperative singular is amare and the passive imperative plural is amamini. Both passive imperatives translate as be loved. For deponent verbs (verbs that are passive in form and active in meaning), the imperative is passive although the meaning is active. The future imperatives for amare are amato, in the singular, and amatote, in the plural. This isnt a form we differentiate in English. In a sense, English imperatives are future imperatives because the person giving the order is asking that something be done in the near or distant future. Memento Remember! is the future imperative of the verb memini to remember. Esto be is another relatively common Latin future imperative. Its plural is, as predicted, estote.