Thursday, December 10, 2009

School project - History of Cricket

Like me you all might be keen to know these facts on cricket. I am a fan of many world famous cricket players. Let us go deeper in to this study

Origin

No one knows when or where cricket began but there is a body of evidence, much of it circumstantial, that strongly suggests the game was devised during Saxon or Norman times by children living in the Weald, an area of dense woodlands and clearings in south-east England that lies across Kent and Sussex. In medieval times, the Weald was populated by small farming and metal-working communities. It is generally believed that cricket survived as a children's game for many centuries before it was increasingly taken up by adults around the beginning of the 17th century

It is quite likely that cricket was devised by children and survived for many generations as essentially a children’s game. Adult participation is unknown before the early 17th century. Possibly cricket was derived from bowls, assuming bowls is the older sport, by the intervention of a batsman trying to stop the ball from reaching its target by hitting it away. Playing on sheep-grazed land or in clearings, the original implements may have been a matted lump of sheep’s wool (or even a stone or a small lump of wood) as the ball; a stick or a crook or another farm tool as the bat; and a stool or a tree stump or a gate (e.g., a wicket gate) as the wicket

The 1st recorded cricket match took place in Kent in 1646 and, by the late 1600s fines were actually handed out for those missed church church to play. Cricket was popular and widely documented in England during the 1700s. In 1706 William Goldwyn published the 1st description of the game. He wrote that 2 teams were 1st seen carrying their curving bats to the venue, choosing a pitch and arguing over the rules. They pitched 2 sets of wickets, each with a "milk-white" bail perched on two stumps; tossed a coin for 1st knock, the umpire called "play" and the "leathern orb" was bowled. They had 4-ball overs, the umpires leant on their staves (which the batsmen had to touch to complete a run), and the scorers sat on a mound making notches.

The 1st written "Laws of Cricket" were established in 1744. They stated, "the principals shall choose from amongst the gentlemen present 2 umpires who shall absolutely decide all disputes. The stumps must be Twenty-two inches high and the bail across them six inches. The ball must be between 5 & 6 ounces, and the two sets of stumps Twenty-two yards apart". There were no limits on the shape or size of the bat. It appears that 40 notches was viewed as a very big score, probably due to the bowlers bowling quickly at shins unprotected by pads. The world's first cricket club was formed in Hambledon in the 1760s and the Marylebone Cricket Club (MCC) was founded in 1787.

During the 1760's and 1770's it became common to pitch the ball through the air, rather than roll it along the ground. This innovation gave bowlers the weapons of deception through the air, length, plus increased pace. It also opened new possibilities for spin and swerve. In response, batsmen had to masters shot selection and timing. One immediate consequence of this was the replacement of the curving bat with the straight one. All of this raised the premium on skill and lessened the influence of rough ground and brute force. It was in the 1770's that the modern game began to take shape.

The weight of the ball was limited to between 5 and a 1/2 and five and 3/4 ounces, and the width of the bat to 4 inches. The latter ruling followed an innings by a batsman called "Shock" White, who appeared with a bat the width of the wicket. In 1774, the first leg before law was published. Also around this time, a third stump became commonplace.

The first reference to it being played as an adult sport was in 1611, when two men in Sussex were prosecuted for playing cricket on Sunday instead of going to church [6]. In the same year, a dictionary defines cricket as a boys' game and this suggests that adult participation was a recent development [

In 1744, the Laws of Cricket were codified for the first time and then amended in 1774, when innovations such as lbw, middle stump and maximum bat width were added. These laws stated that the principals shall choose from amongst the gentlemen present two umpires who shall absolutely decide all disputes. The codes were drawn up by the so-called "Star and Garter Club" whose members ultimately founded MCC at Lord's in 1787. MCC immediately became the custodian of the Laws and has made periodic revisions and recodifications subsequently
The first ever international cricket game was between the USA and Canada in 1844. The match was played at the grounds of the St George's Cricket Club in New York

In 1859, a team of leading English professionals set off to North America on the first-ever overseas tour and, in 1862, the first English team toured Australia.

In 1889 the immemorial four ball over was replaced by a five ball over and then this was changed to the current six balls an over in 1900. Subsequently, some countries experimented with eight balls an over. In 1922, the number of balls per over was changed from six to eight in Australia only. In 1924 the eight ball over was extended to New Zealand and in 1937 to South Africa. In England, the eight ball over was adopted experimentally for the 1939 season; the intention was to continue the experiment in 1940, but first-class cricket was suspended for the Second World War and when it resumed, English cricket reverted to the six ball over. The 1947 Laws of Cricket allowed six or eight balls depending on the conditions of play. Since the 1979/80 Australian and New Zealand seasons, the six ball over has been used worldwide and the most recent version of the Laws in 2000 only permits six ball overs.

Limited overs cricket

In the 1960s, English county teams began playing a version of cricket with games of only one innings each and a maximum number of overs per innings. Starting in 1963 as a knockout competition only, limited overs grew in popularity and in 1969 a national league was created which consequently caused a reduction in the number of matches in the County Championship.

Although many "traditional" cricket fans objected to the shorter form of the game, limited overs cricket did have the advantage of delivering a result to spectators within a single day; it did improve cricket's appeal to younger or busier people; and it did prove commercially successful.

Cricket's newest innovation is Twenty20, essentially an evening entertainment. It has so far enjoyed enormous popularity and has attracted large attendances at matches as well as good TV audience ratings. The inaugural ICC Twenty20 World Cup tournament was held in 2007 with a follow-up event in 2009. The formation of Twenty20 leagues in India - the unofficial Indian Cricket League, which started in 2007, and the official Indian Premier League, starting in 2008 - raised much speculation in the cricketing press about their effect on the future of cricket.

Project on Chemical Elements

When got such a topic, it was hectic to gather information, so sharing with you all


A chemical element can be defined in one of two ways: experimentally or theoretically. Experimentally, an element is any substance that cannot be broken down into any simpler substance. Imagine that you are given a piece of pure iron and asked to break it down using any device or method ever invented by chemists. Nothing you can do will ever change the iron into anything simpler. Iron, therefore, is an element.

The experimental definition of an element can be explained by using a second definition: an element is a substance in which all atoms are of the same kind. If there were a way to look at each of the individual atoms in the bar of pure iron mentioned above, they would all be the same—all atoms of iron. In contrast, a chemical compound, such as iron oxide, always contains at least two different kinds of atoms, in this case, atoms of iron and atoms of oxygen.

Historical background

The concept of a chemical element goes back more than 2,000 years. Ancient Greek philosophers conceived of the idea that some materials are more fundamental, or basic, than others. They listed obviously important materials such as earth, air, fire, and water as possibly being such "elemental" materials. These speculations belonged in the category of philosophy, however, rather than science. The Greeks had no way of testing their ideas to confirm them.

In fact, a few elements were already known long before the speculations of the Greek philosophers. No one at that time called these materials elements or thought of them as being different from the materials we call compounds today. Among the early elements used by humans were iron, copper, silver, tin, and lead. We know that early civilizations knew about and used these elements because of tools, weapons, and pieces of art that remain from the early periods of human history.

Another group of elements was discovered by the alchemists, the semimystical scholars who contributed to the early development of chemistry. These elements include antimony, arsenic, bismuth, phosphorus, and zinc.

Natural and synthetic elements

Ninety-two chemical elements occur naturally on Earth. The others have been made synthetically or artificially in a laboratory. Synthetic elements are usually produced in particle accelerators (devices used to increase the velocity of subatomic particles such as electrons and protons) or nuclear reactors (devices used to control the energy released by nuclear reactions). The first synthetic element to be produced was technetium, discovered in 1937 by Italian American physicist Emilio Segrè (1905–1989) and his colleague C. Perrier. Except for technetium and promethium, all synthetic elements have larger nuclei than uranium.


More than 100 years ago, chemists began searching for ways to organize the chemical elements. At first, they tried listing them by the size (mass) of their nucleus, their atomic mass. Later, they found that using the number of protons in their atomic nuclei was a more effective technique. They invented a property known as atomic number for this organization. The atomic number of an element is defined as the number of protons in the nucleus of an atom of that element. Hydrogen has an atomic number of 1, for example, because the nuclei of hydrogen atoms each contain one—and only one—proton. Similarly, oxygen has an atomic number of 8 because the nuclei of all oxygen atoms contain 8 protons. The accompanying table (periodic table of the elements) contains a list of the known chemical elements arranged in order according to their atomic number.

Notice that the chemical symbol for each element is also included in the table. The chemical symbol of an element is a letter or pair of letters that stands for some given amount of the element, for example, for one atom of the element. Thus, the symbol Ca stands for one atom of calcium, and the symbol W stands for one atom of tungsten. Chemical symbols, therefore, are not really abbreviations.

Chemical elements can be fully identified, therefore, by any one of three characteristics: their name, their chemical symbol, or their atomic number. If you know any one of these identifiers, you immediately know the other two. Saying "Na" to a chemist immediately tells that person that you are referring to sodium, element #11. Similarly, if you say "element 19," the chemist knows that you're referring to potassium, known by the symbol K.

The system of classifying elements used by chemists today is called the periodic table. The law on which the periodic table is based was first discovered almost simultaneously by German chemist Julius Lothar Meyer (1830–1895) and Russian chemist Dmitry Mendeleev (1834–1907) in about 1870. The periodic table is one of the most powerful tools in chemistry because it organizes the chemical elements in groups that have similar physical and chemical properties.

Properties of the elements

One useful way of describing the chemical elements is according to their metallic or nonmetallic character. Most metals are hard with bright, shiny surfaces, often white or grey in color. Since important exceptions to this rule exist, metals are more properly defined according to the way they behave in chemical reactions. Metals, by this definition, are elements that lose electrons to other elements. By comparison, nonmetals are elements that gain electrons from other elements in chemical reactions. (They may be gases, liquids, or solids but seldom look like a metal.) The vast majority (93) of the elements are metals; the rest are nonmetals.


Formation of the Elements

How were the chemical elements formed? Scientists believe the answer to that question lies in the stars and in the processes by which stars are formed. The universe is thought to have been created at some moment in time 12 to 15 billion years ago. Prior to that moment, nothing other than energy is thought to have existed. But something occurred to transform that energy into an enormous explosion: the big bang. In the seconds following the big bang, matter began to form.

According to the big bang theory, the simplest forms of matter to appear were protons and electrons. Some of these protons and electrons combined to form atoms of hydrogen. A hydrogen atom consists of one proton and one electron; it is the simplest atom that can exist. Slowly, over long periods of time, hydrogen atoms began to come together in regions of space forming dense clouds. The hydrogen in these clouds was pulled closer and closer together by gravitational forces. Eventually these clouds of hydrogen were dense enough to form stars.

A star is simply a mass of matter that generates energy by nuclear reactions. The most common of these reactions involves the combination of four hydrogen atoms to make one helium atom. As soon as stars began to form, then, helium became the second element found in the universe.

As stars grow older, they switch from hydrogen-to-helium nuclear reactions to other nuclear reactions. In another such reaction, helium atoms combine to form carbon atoms. Later carbon atoms combine to form oxygen, neon, sodium, and magnesium. Still later, neon and oxygen combine with each other to form magnesium. As these reactions continue, more and more of the chemical elements are formed.

At some point, all stars die. The nuclear reactions on which they depend for their energy come to an end. In some cases, a star's death is dramatic. It may actually blow itself apart, like an atomic bomb. The elements of which the star was made are then spread throughout the universe. They remain in space until they are drawn into the core of other stars or other astronomical bodies, such as our own Earth. If this theory is correct, then the atoms of iron, silver, and oxygen you see around you every day actually started out life in the middle of a star billions of miles away.

The modern definition of an element was first provided by English chemist Robert Boyle (1627–1691). Boyle defined elements as "certain primitive and simple, or perfectly unmingled bodies; which not being made of any other bodies, or of one another, are the ingredients of which all those call'd perfectly mixed bodies are immediately compounded, and into which they are ultimately resolved." For all practical purposes, Boyle's definition of an element has remained the standard working definition for a chemical element ever since.

By the year 1800, no more than about 25 true elements had been discovered. During the next hundred years, however, that situation changed rapidly. By the end of the century, 80 elements were known. The rapid pace of discovery during the 1800s can be attributed to the development of chemistry as a science, to the improved tools of analysis available to chemists, and to the new predictive power provided by the periodic law of 1870.

During the twentieth century, the last remaining handful of naturally occurring elements were discovered and the synthetic elements were first manufactured.

Environmental Pollution

Definition
Gaseous, liquid, or solid substances which (when present in sufficient concentration, for a sufficient time, and under certain conditions) tend to interfere with human comfort, health or welfare, and cause environmental damage. Air pollution causes acid rain, ozone depletion, photochemical smog, and other such phenomenon.
Pollution in broad terms may be defined as an undesirable change in physical, chemical or biological characteristics of air, water and land that may or will harmfully affect human lives, lives of desirable species, living conditions or will deteriorate raw materials resources.Pollutions are substances, chemicals or factors which cause adverse effect on natural quality of any constituent of environment. Pollutions are generally bye products or waste - products.

Types of pollution

There are 7 (seven) types of pollution that are going to be discussed in this note, namely air, water, noise, land, radioactive, marine and thermal. Please proceed to the following links to learn anyone of them.

  1. Air Pollution
  2. Water Pollution
  3. Land Pollution
  4. Noise Pollution
  5. Radioactive Pollution
  6. Thermal Pollution
  7. Marine Pollution

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Air Pollution
Air pollution is the presence of materials in air in such concentration which are harmful to man and his environment. Various causes of air pollution are:
Category
1. Chemical plants
Examples: Petroleum refineries, fertilizers, cements, papermills, ceramic clay products, glass manufacture
Important pollutants: H2S, sulphur oxide, fluorides, organic vapours and dust
2. Crop spraying
Examples: Pesticides and weedicides
Important pollutants: Organophosphates, chlorinated hydrocarbons, lead, arsenic
3. Fuel burning
Examples: Domestic burning, thermal power plants
Important pollutants: Sulphur and nitrogen oxides
4. Metallurgy plants
Examples: Aluminium refineries and steel plant
Important pollutants:Metal flumes (Pb and Zn) fluorides and particulates
5. Nuclear device testing
Examples: Bomb explosions
Important pollutants:Radioactive fall out, Sr-90, Cs-137, C-14 etc.
6. Ore preparations
Examples: Crushing, grinding and screening
Important pollutants: Uranium and beryllium dust, other particulates
7. Spray painting, ink, solvent cleansing
Examples: Printing and chemical separations, furniture, dyeing
Important pollutants: Hydrocarbons and other organic vapours
8. Transportation
Examples: Cars, trucks, aeroplanes and railways
Important pollutants: CO, NO, NO2, Pb, smoke, soot, smoke organic vapours etc.
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2. Water Pollution

Water pollution aversely changes he quality of water. It degrades the quality of water so that it either becomes health hazard or unfit for use. Surface water is never pure. Soil erosion, leaching of minerals from rocks, decaying of organic matter are natural sources of water pollution. Most of water pollution is man-made

Effects of Water Pollution (a)Eutrophication is a natural process observed in lakes and tanks where rich growth of micro-organisms consumes much of dissolved oxygen, depriving other organisms. It is generally found at bottom layers of deep lakes. Addition of excessive plant nutrients increases Eutrophication and is harmful to fish and other aquatic life.
(b) Foam formation in waters by soaps, detergents and alkalies.

(c) Impairment of taste and unpleasant odours in water.
(d) Turbidity which makes water unfit for drinking and industrial purpose.
(e) Inorganic nitrates and phosphates stimulate excessive plant growth in lake and reservoirs


Control of Water Pollution
1. Water hyacinth can purify water polluted by biological and chemical wastes.
2. Strict legislation should be enacted over industries to treat waste water before being discharge into rivers or series.
3. Reclaiming polluted water by proper sewage treatment plants.
4. Domestic and industrial wastes should be destroyed by constructing composite pit.
5. Hot water should be cooled suitably before adding to river water.
6. Oxidation ponds can be used in removing low level of radioactive wastes.
7. Sewage pollutions are subjected to chemical treatment to change them into non-toxic substances.
8. Very specific and less stable chemicals should be used in manufacture of insecticides to reduce water pollution.

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Soil Pollution

Soil pollution is standing up as an havoc in densely populated and developing countries. Since soil-formation is slow it is regarded as non-renewable resource. Soil pollution is the effect of dumping and disposal of wastes, application of agrochemicals or indirect result of air pollution (acid rain). Pesticides reduce the population and number of species of living organisms which effect structure and fertility of the soil. Several pesticides and their degradation products enter the food chain via. plants.

Improper sanitation and unhygienic practices of the people of developing countries pollute the soil. Innumerable pathogens present in these wastes contaminate the vegetable crops and cause several health hazards for man and domesticated animals. Biological sources are a minor factor in altering soil composition.

Control of Soil Pollution
1. Use of pesticides should be minimized.
2. Use of fertilisers should be judicious.
3. Cropping techniques should be improved to prevent growth of weeds.
4. Special pits should be selected for dumping wastes.
5. Controlled grazing and forest management.
6. Wind breaks and wind shield in areas exposed to wind erosin
7. Planning of soil binding grasses along banks and slopes prone to rapid erosin.
8. Afforestation and reforestation.

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Noise Pollution

Noise is defined as 'unwanted sounds' being 'dumped' into atmosphere to disturb the unwilling ears. It effects our physiological and mental health. A sound of over 115 decides is harmful for ears. They city noise is often sufficient to deafen people gradually, at least partially with advancing age. Sources of Noise Pollution High intensity sound from industrial machines, supersonic aeroplanes, bomb blasts, exploding of crackers, blaring radios and loudspeakers, slogans shouting city crowd, traffic noise etc.

Effects of Noise Pollution
1. It interferes with human communication
2. Prolonged exposure leads to deafen our ears or permanent loss of hearing.
3. It causes anxiety, reaction of stress and tension, may produce fright and even heart failure to heart patients.
4. Its long exposure can cause hormonal imbalance leading to adverse disorders like increased heart beat, constriction of blood vessels, increase in cholesterol level, high blood pressure and hypertension and production of gastro intestinal problems like peptic ulcers.
5. It can impair development of nervous system of unborn babies leading to abnormal behaviour in life.

Control of Noise PollutionIt depends upon three factors:
1. To reduce the source of noise.
2. To put checks in path of its transmission.
3. To safeguard the receive of the noise. For this to happen vehicular traffic should be diverted away from dwelling sites. Proper designing of machines can reduce loss due to noise. Acoustic furnishing (absorbing techniques) should be extensively employed. There should be legal enforcement of restrictions on noise pollution.

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Radioactive Pollution

Despite the advantage of nuclear as a clean energy, the big concern is the waste resulted from nuclear reaction, which is a form of pollution, called radioactivity. Radioactivity is a form of radiation (a form of energy that travels through space). Some elements in this world are naturally radioactive while some others are made to be. Radioactivity is emitted when a radioactive element become unstable and begin to decay in the attempt to regain their molecular stability. When an element decays, it emits energy and small particles. If it’s still radioactive, it will repeat the process, until it finally regains its molecular stability and stop decaying. The time that it takes for half way of decaying process is called half-life, and this differs for each radioactive element. It possibly takes up to 4.5 billion years (Uranium 238) and as short as 8 days (Iodine 131). This process constantly remains, not considering external factors such as pressure or temperature.

There are commonly three types of radiation, namely:

Alpha particles, can be blocked by a piece of paper and human skin.

Beta particles can penetrate through skin, while can be blocked by some pieces of glass and metal.

Gamma rays can penetrate easily to human skin and damage cells on its way through, reaching far, and can only be blocked by a very thick, strong, massive piece of concrete.

We can classify major sources that lead to radioactive pollution to the following categories:
· nuclear power plants
· nuclear weapon
· transportation
· disposal of nuclear waste uranium mining

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Thermal Pollution:

It is caused by addition of hot effluents and hot water bodies. Warm water contains less oxygen. So there is decrease in rate of decomposition of organic matter. Green algae are replaced by less desirable blue green algae. Many animals fail to multiply. Trout eggs fail to hatch while salmon does not spawm at higher temperature.Agriculture sources.Use of high yielding varieties of crops increased the demand for fertilizers are carried to ground water by leaching. They are also added through surface run off. Many pesticides are non-degradable. Huge amount of animal excreta-dung, piggeries are either discharged into grazing fields or dumped into pits.

These are later carried either by surface run-off or get percolated into under-grounded water. Lack of potable drinking water supply, unhygienic habits and poor waster disposal have aggravated problem of water pollution. To evade water pollution regulations and to avoid cost of treatment, industries are disposing off their wastes on ground which has lead to large scale pollution of underground water.

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Marine Pollution.

Oceans are ultimate sink of all natural and man-made pollutants. Marine ecosystems lack decomposing capacity. Artificial discharges cause localised pollution especially in coastal areas. Main sources are navigational oil discharge, grease and petroleum products, detergents, sewage and garbage including radioactive wastes.