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TRANSPORTATION

Transportation in India

NAMES OF TRANSPORTATION USED IN INDIA

Cycle rickshaws 

Bullock carts/Horse carriages

Bicycles

Rickshaws

Bus

Ambulance

Boat

Train

Air plane

Metro

 Transports from one location to another. Modes of transport include air, land (rail and road), water, cable, pipeline and space. The field can be divided into infrastructure, vehicles and operation .or or transportation is the movement of humans, animals and goo

WHAT DO YOU MEAN  BY TRANSPORTATION SYSTEM

A Transportation System or mode is a system for moving persons or goods consisting of three components: (a) The vehicle (equipment) is what moves objects or traffic (people, goods

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DOGS

DOGS

There are more than 150 dog breeds, divided into 8 classes: sporting, hound, working, terrier, toy, non-sporting, herding, and miscellaneous.

– According to a recent survey, the most popular name for a dog is Max. Other popular names include Molly, Sam, Zach, and Maggie.

– Dogs can vary in size from a 36 inch (150+ lb.) Great Dane to a 2 lb. Chihuahua.

– Puppies and kittens can be adopted as early as 8 weeks of age. Until then, they should stay with their moms and littermates.

– About 1/3 of the dogs that are surrendered to animal shelters are purebred dogs.

– Contrary to popular belief, dogs do not sweat by salivating. They sweat through the pads of their feet.

– Dogs may not have as many taste buds as we do (they have about 1,700 on their tongues, while we humans have about 9,000), but that doesn’t mean they’re not discriminating eaters. They have over 200 million scent receptors in their noses (we have only 5 million) so it’s important that their food smells good and tastes good.

– The term “dog days” has nothing to do with dogs. It dates back to Roman times, when it was believed that Sirius, the Dog Star, added its heat to that of the sun from July 3 to August 11, creating exceptionally high temperatures.

– Did you know they were female? Toto’s role in The Wizard of Oz was played by a female Cairn Terrier named Terry, and the Taco Bell dog is actually a female Chihuahua named Gidget.

– Former US President Teddy Roosevelt had a Pit Bull named Pete.

– An adult dog has 42 teeth.

– If a dog isn’t spayed or neutered, a female dog, her mate and their offspring can product 67,000 dogs in 6 years.

– The most successful mountain rescue dog ever was a St Bernard named Barry, who lived during the early 1800’s and saved 40 lives.

– It was recently discovered that dogs do see in color, just not as vivid as we see.

– Nearly all but two breeds of dogs have pink tongues: the Chow Chow and the Shar-pei both have black tongues.

– The Poodle haircut was originally meant to improve the dog’s swimming abilities as a retriever, with the pom-poms left in place to warm their joints.

– The top five favorite breeds of dogs in the US are: Labrador Retriever, Golden Retriever, German Shepherd, Beagle, and Dachshund.

– The Basenji is the only barkless dog in the world.

– Greyhounds can reach a speed of up to 45 miles per hour.

– When a puppy is born, he is blind, deaf, and toothless.

– All dogs, regardless of breed, are direct descendants of wolves and technically of the same species.

– A dog’s whiskers — found on the muzzle, above the eyes and below the jaws — are technically known as vibrissae. They are touch-sensitive hairs than actually sense minute changes in airflow.

– Dogs are capable of locating the source of a sound in 6/100ths of a second by using their swiveling ears like radar dishes.

CATS

CATS

To their owners, cats will always be fascinating creatures. So here are a few facts about cats you may find interesting.

The cat

  • Cats have been domesticated for around 4,000 years. While they were once valued for their hunting abilities, they are now valued for their companionship and loving behaviour.
  • While not well known, the collective nouns used for cats and kittens are a clowder of cats and a kindle of kittens.
  • Our domestic cats are known as little cats. They differ from large cats such as lions and tigers because they are naturally active at night and can purr.
  • Cats are now the most popular pet in the UK and in the US.

The feline body & behaviour

With 48 recognised cat breeds and pedigrees in Australia plus an endless combination of cross breeds it’s amazing just how different each cat can look and behave. But there are many amazing physical characteristics that all cats possess, read on for more fascinating facts about your feline friend.

  • Cats have 30 teeth (dogs have 42) and most of us know how sharp they are!
  • Cats have a reflective layer in their eyes, known as the tapetum lucidum, which magnifies incoming light allowing them to see up to 6 times better than humans can in low light. Cats (as well as dogs) also have a ‘third eyelid’ called the nictitating membrane which is found on the inside corner of the eye which is an extra protective function of the eye.
  • Cats have 32 muscles in their ears (humans have only 12). This gives the ear mobility, enabling it to precisely locate prey such as mice or the opening of their cat food! Cats can also hear frequencies that are both below and above those that can be heard by humans. The ear also has the job of helping to maintain balance and the ability to right themselves when falling – which is where the phrase “Cats always land on their feet” came from.
  • More cats are left-pawed than right.
  • The texture of cat food is more important to cats than taste and cats can often be quite fussy about the smells of food. If your cat have ever licked you, you might compare the feel of their tongue to that of coarse sandpaper – that’s because a cats’ tongue is covered in tiny backwards facing thorn like barbs that guide food to the back of the mouth. These rough tongues are also perfectly designed for grooming and lapping up water.
  • Cats can retract their front claws. This keeps them sharp so they can be used for climbing and of course, as effective weapons!
  • Cats rub against us and scratch as a form of communication. They have scent glands on their cheeks and paws, so rubbing against us or scratching on vertical surfaces transfers their scent.
  • Around 75% of cats respond to catnip. This herb stimulates those cats that are genetically programmed to respond.
  • Those long whiskers around your cats’ mouth and face which form a vital part of their sense of touch. These whiskers are attached to nerve cells and are used to judge the size of openings as well as providing your cat information about everything he/she touches, as well as shifts in air pressure.
  • Cats can travel at speeds of up to 30km per hour.
  • The largest breed of cat in Australia is the Maine . Males can regularly weigh up to 12kgs!

Feline- human relationship

  • Cats are good for our health. People who own cats have a lower risk of cardio-vascular disease than non-cat owners. Elderly cat owners suffer less from depression and loneliness than non-cat owners.
  • Cats can be trained. Teach your cat to share a “high five” with you by rewarding her with a special treat every time she lifts her paw.
  • Cats need to interact with people from two weeks of age to enable them to be social towards humans. After 16 weeks of age it is very difficult to tame a cat.
  • Psychological studies have shown that cat owners are more logical and practical than dog owners. They tend to be more introverted than dog owners. Cat owners, however, tell more stories about their cats than dog owners.
  • The record number of cats kept by any one person was by an owner named Jack Wright, from Ontario, Canada who kept 689 cats!

Can’t get enough cat facts? Check out our other cat care topics.

 

About Dr Joanne Righetti

Dr Joanne RighettiDr Joanne Righetti is an animal behaviourist, educating the public and professionals in all aspects of the human–animal relationship. Her background is in zoology, with a PhD in animal behaviour and a counselling diploma – qualifications which enable her to work with all sorts of animals – including the human variety! Joanne likes to help pet owners understand their pet’s behaviour and solve any pet behaviour problems. She also consults to a variety of organisations including non-profit organisations, commercial companies and councils and is involved in a variety of media including regular spots on radio. Joanne is an honorary associate of the Faculty of Veterinary Sciences, University of Sydney. Find out more about Joanne at www.petproblemsolved.com.au

MATHEMATICS

MATHEMATICS

Mathematics is the science that deals with the logic of shape, quantity and arrangement. Math is all around us, in everything we do. It is the building block for everything in our daily lives, including mobile devices, architecture (ancient and modern), art, money, engineering, and even sports.

Since the beginning of recorded history, mathematic discovery has been at the forefront of every civilized society, and in use in even the most primitive of cultures. The needs of math arose based on the wants of society. The more complex a society, the more complex the mathematical needs. Primitive tribes needed little more than the ability to count, but also relied on math to calculate the position of the sun and the physics of hunting.

Several civilizations — in China, India, Egypt, Central America and Mesopotamia — contributed to mathematics as we know it today. The Sumerians were the first people to develop a counting system. Mathematicians developed arithmetic, which includes basic operations, multiplication, fractions and square roots. The Sumerians’ system passed through the Akkadian Empire to the Babylonians around 300 B.C. Six hundred years later, in America, the Mayans developed elaborate calendar systems and were skilled astronomers. About this time, the concept of zero was developed.

As civilizations developed, mathematicians began to work with geometry, which computes areas and volumes to make angular measurements and has many practical applications. Geometry is used in everything from home construction to fashion and interior design.

Geometry went hand in hand with algebra, invented in the ninth century by a Persian mathematician, Mohammed ibn-Musa al-Khowarizmi. He also developed quick methods for multiplying and diving numbers, which are known as algorithms — a corruption of his name.

Algebra offered civilizations a way to divide inheritances and allocate resources. The study of algebra meant mathematicians were solving linear equations and systems, as well as quadratics, and delving into positive and negative solutions. Mathematicians in ancient times also began to look at number theory. With origins in the construction of shape, number theory looks at figurate numbers, the characterization of numbers, and theorems.

Math and the Greeks

The study of math within early civilizations was the building blocks for the math of the Greeks, who developed the model of abstract mathematics through geometry. Greece, with its incredible architecture and complex system of government, was the model of mathematic achievement until modern times. Greek mathematicians were divided into several schools:

  • The Ionian School, founded by Thales, who is often credited for having given the first deductive proofs and developing five basic theorems in plane geometry.
  • The Pythagorean School, founded by Pythagoras, who studied proportion, plane and solid geometry, and number theory.
  • The Eleatic School, which included Zeno of Elea, famous for his four paradoxes.
  • The Sophist School, which is credited for offering higher education in the advanced Greek cities. Sophists provided instruction on public debate using abstract reasoning.
  • The Platonic School, founded by Plato, who encouraged research in mathematics in a setting much like a modern university.
  • The School of Eudoxus, founded by Eudoxus, who developed the theory of proportion and magnitude and produced many theorems in plane geometry
  • The School of Aristotle, also known as the Lyceum, was founded by Aristotle and followed the Platonic school.

In addition to the Greek mathematicians listed above, a number of Greeks made an indelible mark on the history of mathematics. Archimedes, Apollonius, Diophantus, Pappus, and Euclid all came from this era. To better understand the sequence and how these mathematicians influenced each other, visit this timeline.

During this time, mathematicians began working with trigonometry. Computational in nature, trigonometry requires the measurement of angles and the computation of trigonometric functions, which include sine, cosine, tangent, and their reciprocals. Trigonometry relies on the synthetic geometry developed by Greek mathematicians like Euclid. For example, Ptolemy’s theorem gives rules for the chords of the sum and difference of angles, which correspond to the sum and difference formulas for sines and cosines. In past cultures, trigonometry was applied to astronomy and the computation of angles in the celestial sphere.

After the fall of Rome, the development of mathematics was taken on by the Arabs, then the Europeans. Fibonacci was one of the first European mathematicians, and was famous for his theories on arithmetic, algebra, and geometry. The Renaissance led to advances that included decimal fractions, logarithms, and projective geometry. Number theory was greatly expanded upon, and theories like probability and analytic geometry ushered in a new age of mathematics, with calculus at the forefront.

Development of calculus

In the 17th century, Isaac Newton and Gottfried Leibniz independently developed the foundations for calculus. Calculus development went through three periods: anticipation, development and rigorization. In the anticipation stage, mathematicians were attempting to use techniques that involved infinite processes to find areas under curves or maximize certain qualities. In the development stage, Newton and Leibniz brought these techniques together through the derivative and integral. Though their methods were not always logically sound, mathematicians in the 18th century took on the rigorization stage, and were able to justify them and create the final stage of calculus. Today, we define the derivative and integral in terms of limits.

In contrast to calculus, which is a type of continuous mathematics, other mathematicians have taken a more theoretical approach. Discrete mathematics is the branch of math that deals with objects that can assume only distinct, separated value. Discrete objects can be characterized by integers, whereas continuous objects require real numbers. Discrete mathematics is the mathematical language of computer science, as it includes the study of algorithms. Fields of discrete mathematics include combinatorics, graph theory, and the theory of computation.

People often wonder what relevance mathematicians serve today. In a modern world, math such as applied mathematics is not only relevant, it’s crucial. Applied mathematics is the branches of mathematics that are involved in the study of the physical, biological, or sociological world. The idea of applied math is to create a group of methods that solve problems in science. Modern areas of applied math include mathematical physics, mathematical biology, control theory, aerospace engineering, and math finance. Not only does applied math solve problems, but it also discovers new problems or develops new engineering disciplines. Applied mathematicians require expertise in many areas of math and science, physical intuition, common sense, and collaboration. The common approach in applied math is to build a mathematical model of a phenomenon, solve the model, and develop recommendations for performance improvement.

While not necessarily an opposite to applied mathematics, pure mathematics is driven by abstract problems, rather than real world problems. Much of what’s pursued by pure mathematicians can have their roots in concrete physical problems, but a deeper understanding of these phenomena brings about problems and technicalities. These abstract problems and technicalities are what pure mathematics attempts to solve, and these attempts have led to major discoveries for mankind, including the Universal Turing Machine, theorized by Alan Turing in 1937. The Universal Turing Machine, which began as an abstract idea, later laid the groundwork for the development of the modern computer. Pure mathematics is abstract and based in theory, and is thus not constrained by the limitations of the physical world.

According to one pure mathematician, pure mathematicians prove theorems, and applied mathematicians construct theories. Pure and applied are not mutually exclusive, but they are rooted in different areas of math and problem solving. Though the complex math involved in pure and applied mathematics is beyond the understanding of most average Americans, the solutions developed from the processes have affected and improved the lives of all.

 

PAINT

PAINT

Related image

In 2003 and 2004, South African archeologists reported finds in Blombos Cave of a 100,000-year-old human-made ochre-based mixture that could have been used like paint.[1][2] Further excavation in the same cave resulted in the 2011 report of a complete toolkit for grinding pigments and making a primitive paint-like substance.[2][3] Cave paintings drawn with red or yellow ochre, hematite, manganese oxide, and charcoal may have been made by early sapiens as long as 40,000 years ago.

Ancient colored walls at Dendera, Egypt, which were exposed for years to the elements, still possess their brilliant color, as vivid as when they were painted about 2,000 years ago. The Egyptians mixed their colors with a gummy substance, and applied them separately from each other without any blending or mixture. They appear to have used six colors: white, black, blue, red, yellow, and green. They first covered the area entirely with white, then traced the design in black, leaving out the lights of the ground color. They used minium for red, and generally of a dark tinge.

Pliny mentions some painted ceilings in his day in the town of Ardea, which had been done prior to the foundation of Rome. He expresses great surprise and admiration at their freshness, after the lapse of so many centuries.

Paint was made with the yolk of eggs and therefore, the substance would harden and adhere to the surface it was applied to. Pigment was made from plants, sand, and different soils. Most paints used either oil or water as a base (the diluent, solvent or vehicle for the pigment).

A still extant example of 17th-century house oil painting is Ham House in Surrey, England, where a primer was used along with several undercoats and an elaborate decorative overcoat; the pigment and oil mixture would have been ground into a paste with a mortar and pestle. The process was done by hand by the painters and exposed them to lead poisoning due to the white-lead powder.

In 1718, Marshall Smith invented a “Machine or Engine for the Grinding of Colours” in England. It is not known precisely how it operated, but it was a device that increased the efficiency of pigment grinding dramatically. Soon, a company called Emerton and Manby was advertising exceptionally low-priced paints that had been ground with labour-saving technology:

One Pound of Colour ground in a Horse-Mill will paint twelve Yards of Work, whereas Colour ground any other Way, will not do half that Quantity.

By the proper onset of the Industrial Revolution, paint was being ground in steam-powered mills and an alternative to lead-based pigments was found in a white derivative of zinc oxide. Interior house painting increasingly became the norm as the 19th century progressed, both for decorative reasons and because the paint was effective in preventing the walls rotting from damp. Linseed oil was also increasingly used as an inexpensive binder.

In 1866, Sherwin-Williams in the United States opened as a large paint-maker and invented a paint that could be used from the tin without preparation.

It was not until the stimulus of World War II created a shortage of linseed oil in the supply market that artificial resins, or alkyds, were invented. Cheap and easy to make, they also held the color well and lasted for a long time.[4][not in citation given][citation needed]

Components

Vehicle

The vehicle is composed of the binder; or, if it is necessary to thin the binder with a diluent like solvent or water, it is the combination of binder and diluent.[5][6] In this case, once the paint has dried or cured very nearly all of the diluent has evaporated and only the binder is left on the coated surface. Thus, an important quantity in coatings formulation is the “vehicle solids”, sometimes called the “resin solids” of the formula. This is the proportion of the wet coating weight that is binder, i.e. the polymer backbone of the film that will remain after drying or curing is complete.

Binder or film former

The binder is the film-forming component of paint.[7] It is the only component that is always present among all the various types of formulations. Many binders are too thick to be applied and must be thinned. The type of thinner, if present, varies with the binder.

The binder imparts properties such as gloss, durability, flexibility, and toughness.[8]

Binders include synthetic or natural resins such as alkyds, acrylics, vinyl-acrylics, vinyl acetate/ethylene (VAE), polyurethanes, polyesters, melamine resins, epoxy, silanes or siloxanes or oils.

Binders can be categorized according to the mechanisms for film formation. Thermoplastic mechanisms include drying and coalescence. Drying refers to simple evaporation of the solvent or thinner to leave a coherent film behind. Coalescence refers to a mechanism that involves drying followed by actual interpenetration and fusion of formerly discrete particles. Thermoplastic film-forming mechanisms are sometimes described as “thermoplastic cure” but that is a misnomer because no chemical curing reactions are required to knit the film. Thermosetting mechanisms, on the other hand, are true curing mechanism that involve chemical reaction(s) among the polymers that make up the binder.[9]

Thermoplastic mechanisms: Some films are formed by simple cooling of the binder. For example, encaustic or wax paints are liquid when warm, and harden upon cooling. In many cases, they resoften or liquify if reheated.

Paints that dry by solvent evaporation and contain the solid binder dissolved in a solvent are known as lacquers. A solid film forms when the solvent evaporates. Because no chemical crosslinking is involved, the film can re-dissolve in solvent; as such, lacquers are unsuitable for applications where chemical resistance is important. Classic nitrocellulose lacquers fall into this category, as do non-grain raising stains composed of dyes dissolved in solvent. Performance varies by formulation, but lacquers generally tend to have better UV resistance and lower corrosion resistance than comparable systems that cure by polymerization or coalescence.

The paint type known as Emulsion in the UK and Latex in the United States is a water-borne dispersion of sub-micrometer polymer particles. These terms in their respective countries cover all paints that use synthetic polymers such as acrylic, vinyl acrylic (PVA), styrene acrylic, etc. as binders.[10] The term “latex” in the context of paint in the United States simply means an aqueous dispersion; latex rubber from the rubber tree is not an ingredient. These dispersions are prepared by emulsion polymerization. Such paints cure by a process called coalescence where first the water, and then the trace, or coalescing, solvent, evaporate and draw together and soften the binder particles and fuse them together into irreversibly bound networked structures, so that the paint cannot redissolve in the solvent/water that originally carried it. The residual surfactants in paint, as well as hydrolytic effects with some polymers cause the paint to remain susceptible to softening and, over time, degradation by water. The general term of latex paint is usually used in the United States, while the term emulsion paint is used for the same products in the UK and the term latex paint is not used at all.

Thermosetting mechanisms: Paints that cure by polymerization are generally one- or two-package coatings that polymerize by way of a chemical reaction, and cure into a crosslinked film. Depending on composition they may need to dry first, by evaporation of solvent. Classic two-package epoxies or polyurethanes would fall into this category.[11]

The “drying oils”, counter-intuitively, actually cure by a crosslinking reaction even if they are not put through an oven cycle and seem to simply dry in air. The film formation mechanism of the simplest examples involve first evaporation of solvents followed by reaction with oxygen from the environment over a period of days, weeks and even months to create a crosslinked network.[5] Classic alkyd enamels would fall into this category. Oxidative cure coatings are catalyzed by metal complex driers such as cobalt naphthenate.

Recent environmental requirements restrict the use of volatile organic compounds (VOCs), and alternative means of curing have been developed, generally for industrial purposes. UV curing paints, for example, enable formulation with very low amounts of solvent, or even none at all. This can be achieved because of the monomers and oligomers used in the coating have relatively very low molecular weight, and are therefore low enough in viscosity to enable good fluid flow without the need for additional thinner. If solvent is present in significant amounts, generally it is mostly evaporated first and then crosslinking is initiated by ultraviolet light. Similarly, powder coatings contain little or no solvent. Flow and cure are produced by heating of the substrate after electrostatic application of the dry powder.[12]

Combination mechanisms: So-called “catalyzed” lacquers” or “crosslinking latex” coatings are designed to form films by a combination of methods: classic drying plus a curing reaction that benefits from the catalyst. There are paints called plastisols/organosols, which are made by blending PVC granules with a plasticiser. These are stoved and the mix coalesces.

Diluent or solvent or thinner

The main purposes of the diluent are to dissolve the polymer and adjust the viscosity of the paint. It is volatile and does not become part of the paint film. It also controls flow and application properties, and in some cases can affect the stability of the paint while in liquid state. Its main function is as the carrier for the non volatile components. To spread heavier oils (for example, linseed) as in oil-based interior house paint, a thinner oil is required. These volatile substances impart their properties temporarily—once the solvent has evaporated, the remaining paint is fixed to the surface.

This component is optional: some paints have no diluent.

Water is the main diluent for water-borne paints, even the co-solvent types.

Solvent-borne, also called oil-based, paints can have various combinations of organic solvents as the diluent, including aliphatics, aromatics, alcohols, ketones and white spirit. Specific examples are organic solvents such as petroleum distillate, esters, glycol ethers, and the like. Sometimes volatile low-molecular weight synthetic resins also serve as diluents.

Pigment and filler

Pigments are granular solids incorporated in the paint to contribute color. Fillers are granular solids incorporate to impart toughness, texture, give the paint special properties,[13] or to reduce the cost of the paint. Alternatively, some paints contain dyes instead of or in combination with pigments.

Pigments can be classified as either natural or synthetic. Natural pigments include various clays, calcium carbonate, mica, silicas, and talcs. Synthetics would include engineered molecules, calcined clays, blanc fixe, precipitated calcium carbonate, and synthetic pyrogenic silicas.

Hiding pigments, in making paint opaque, also protect the substrate from the harmful effects of ultraviolet light. Hiding pigments include titanium dioxide, phthalo blue, red iron oxide, and many others.

Fillers are a special type of pigment that serve to thicken the film, support its structure and increase the volume of the paint. Fillers are usually cheap and inert materials, such as diatomaceous earth, talc, lime, barytes, clay, etc. Floor paints that must resist abrasion may contain fine quartz sand as a filler. Not all paints include fillers. On the other hand, some paints contain large proportions of pigment/filler and binder.

Some pigments are toxic, such as the lead pigments that are used in lead paint. Paint manufacturers began replacing white lead pigments with titanium white (titanium dioxide), before lead was banned in paint for residential use in 1978 by the US Consumer Product Safety Commission. The titanium dioxide used in most paints today is often coated with silica/alumina/zirconium for various reasons, such as better exterior durability, or better hiding performance (opacity) promoted by more optimal spacing within the paint film.[14]

Micaceous iron oxide (MIO) is another alternative to lead for protection of steel, giving more protection against water and light damage than most paints. When MIO pigments are ground into fine particles, most cleave into shiny layers, which reflect light, thus minimising UV degradation and protecting the resin binder. Most pigments used in paint tend to be spherical, but lamellar pigments, such as glass flake and MIO have overlapping plates, which impede the path of water molecules.[15] For optimum performance MIO should have a high content of thin flake-like particles resembling mica. ISO 10601 sets two levels of MIO content.[16] MIO is often derived from a form of hematite.

Additives

Besides the three main categories of ingredients, paint can have a wide variety of miscellaneous additives, which are usually added in small amounts, yet provide a significant effect on the product. Some examples include additives to modify surface tension, improve flow properties, improve the finished appearance, increase wet edge, improve pigment stability, impart antifreeze properties, control foaming, control skinning, etc. Other types of additives include catalysts, thickeners, stabilizers, emulsifiers, texturizers, adhesion promoters, UV stabilizers, flatteners (de-glossing agents), biocides to fight bacterial growth, and the like.

Additives normally do not significantly alter the percentages of individual components in a formulation.[17]

Color-changing paint

Various technologies exist for making paints that change color. Thermochromic paints and coatings contain materials that change conformation when heat is applied or removed, and so they change color. Liquid crystals have been used in such paints, such as in the thermometer strips and tapes used in aquaria and novelty/promotional thermal cups and straws. These materials are used to make eyeglasses.

Color-changing paints can also be made by adding halochrome compounds or other organic pigments. One patent[18] cites use of these indicators for wall coating applications for light colored paints. When the paint is wet it is pink in color but upon drying it regains its original white color. As cited in patent, this property of the paint enabled two or more coats to be applied on a wall properly and evenly. The previous coats having dried would be white whereas the new wet coat would be distinctly pink. Ashland Inc. introduced foundry refractory coatings with similar principle in 2005[19][20] for use in foundries.

Electrochromic paints change color in response to an applied electric current. Car manufacturer Nissan has been reportedly working on an electrochromic paint, based on particles of paramagnetic iron oxide. When subjected to an electromagnetic field the paramagnetic particles change spacing, modifying their color and reflective properties. The electromagnetic field would be formed using the conductive metal of the car body.[21] Electrochromic paints can be applied to plastic substrates as well, using a different coating chemistry. The technology involves using special dyes that change conformation when an electric current is applied across the film itself. This new technology has been used to achieve glare protection at the touch of a button in passenger airplane windows.

Art

Watercolors as applied with a brush

Since the time of the Renaissance, siccative (drying) oil paints, primarily linseed oil, have been the most commonly used kind of paints in fine art applications; oil paint is still common today. However, in the 20th century, water-based paints, including watercolors and acrylic paints, became very popular with the development of acrylic and other latex paints. Milk paints (also called casein), where the medium is derived from the natural emulsion that is milk, were popular in the 19th century and are still available today. Egg tempera (where the medium is an emulsion of raw egg yolk mixed with oil) is still in use as well, as are encaustic wax-based paints. Gouache is a variety of opaque watercolor that was also used in the Middle Ages and Renaissance for manuscript illuminations. The pigment was often made from ground semiprecious stones such as lapis lazuli and the binder made from either gum arabic or egg white. Gouache, also known as ‘designer color’ or ‘body color’ is commercially available today.

Poster paint has been used primarily in the creation of student works, or by children.

The “painter’s mussel“, a European freshwater mussel. Individual shell valves were used by artists as a small dish for paint.

Application

Paint can be applied as a solid, a gaseous suspension (aerosol) or a liquid. Techniques vary depending on the practical or artistic results desired.

As a solid (usually used in industrial and automotive applications), the paint is applied as a very fine powder, then baked at high temperature. This melts the powder and causes it to adhere to the surface. The reasons for doing this involve the chemistries of the paint, the surface itself, and perhaps even the chemistry of the substrate (the object being painted). This is called “powder coating” an object.

As a gas or as a gaseous suspension, the paint is suspended in solid or liquid form in a gas that is sprayed on an object. The paint sticks to the object. This is called “spray painting” an object. The reasons for doing this include:

  • The application mechanism is air and thus no solid object touches the object being painted;
  • The distribution of the paint is uniform, so there are no sharp lines;
  • It is possible to deliver very small amounts of paint;
  • A chemical (typically a solvent) can be sprayed along with the paint to dissolve together both the delivered paint and the chemicals on the surface of the object being painted;
  • Some chemical reactions in paint involve the orientation of the paint molecules.

In the liquid application, paint can be applied by direct application using brushes, paint rollers, blades, scrapers, other instruments, or body parts such as fingers and thumbs.

Rollers generally have a handle that allows for different lengths of poles to be attached, allowing painting at different heights. Generally, roller application requires two coats for even color. A roller with a thicker nap is used to apply paint on uneven surfaces. Edges are often finished with an angled brush.

  • Using the finish flat one would most likely use a 1/2″ nap roller
  • Using the finish eggshell one would most likely use a 3/8″ nap roller
  • Using the finish satin or pearl one would most likely use a 3/8″ nap roller
  • Using the finish semi-gloss or gloss one would most likely use a 3/16″ nap roller

[22]

After liquid paint is applied, there is an interval during which it can be blended with additional painted regions (at the “wet edge”) called “open time”. The open time of an oil or alkyd-based emulsion paint can be extended by adding white spirit, similar glycols such as Dowanol (propylene glycol ether) or open time prolongers. This can also facilitate the mixing of different wet paint layers for aesthetic effect. Latex and acrylic emulsions require the use of drying retardants suitable for water-based coatings.

Paint application by spray is the most popular method in industry. In this, paint is aerosolized by the force of compressed air or by the action of high pressure compression of the paint itself, and the paint is turned into small droplets that travel to the article to be painted. Alternate methods are airless spray, hot spray, hot airless spray, and any of these with an electrostatic spray included. There are numerous electrostatic methods available.

Dipping used to be the norm for objects such as filing cabinets, but this has been replaced by high speed air turbine driven bells with electrostatic spray. Car bodies are primed using cathodic elephoretic primer, which is applied by charging the body depositing a layer of primer. The unchanged residue is rinsed off and the primer stoved.

Many paints tend to separate when stored, the heavier components settling to the bottom, and require mixing before use. Some paint outlets have machines for mixing the paint by shaking the can vigorously for a few minutes.

The opacity and the film thickness of paint may be measured using a drawdown card.

Water-based paints tend to be the easiest to clean up after use; the brushes and rollers can be cleaned with soap and water.

Proper disposal of left over paint is a challenge. Sometimes it can be recycled: Old paint may be usable for a primer coat or an intermediate coat, and paints of similar chemistry can be mixed to make a larger amount of a uniform color.

To dispose of paint it can be dried and disposed of in the domestic waste stream, provided that it contains no prohibited substances (see container). Disposal of liquid paint usually requires special handling and should be treated as hazardous waste, and disposed of according to local regulations.[23][24]

Product variants

A collection of cans of paint and variants

A huge collection of different kinds of spray cans, markers, paints and inks in the underground graffiti shop. Russia, Tver City, 2011.
  • Primer is a preparatory coating put on materials before applying the paint itself. The primed surface ensures better adhesion of the paint, thereby increasing the durability of the paint and providing improved protection for the painted surface. Suitable primers also may block and seal stains, or hide a color that is to be painted over.
  • Emulsion paints are water-based paints in which the paint material is dispersed in a liquid that consists mainly of water. For suitable purposes this has advantages in fast drying, low toxicity, low cost, easier application, and easier cleaning of equipment, among other factors.
  • Flat Finish paint is generally used on ceilings or walls that are in bad shape. This finish is useful for hiding imperfections in walls and it is economical in effectively covering relatively great areas. However this finish is not easily washable and is subject to staining.
  • Matte Finish is generally similar to flat finish, but such paints commonly offer superior washability and coverage. (See Gloss and matte paint.)
  • Eggshell Finish has some sheen, supposedly like that of the shell on an egg. This finish provides great washability, but is not very effective at hiding imperfections on walls and similar surfaces. Eggshell finish is valued for bathrooms because it is washable and water repellent, so that it tends not to peel in a wet environment.
  • Pearl (Satin) Finish is very durable in terms of washability and resistance to moisture, even in comparison to eggshell finish. It protects walls from dirt, moisture and stains. Accordingly, it is exceptionally valuable for bathrooms, furniture, and kitchens, but it is shinier than eggshell, so it is even more prone to show imperfections.
  • Semi-Gloss Finish typically is used on trim to emphasise detail and elegance, and to show off woodwork, such as on doors and furniture. It provides a shiny surface and provides good protection from moisture and stains on walls. Its gloss does however emphasise imperfections on the walls and similar surfaces. It is popular in schools and factories where washability and durability are the main considerations.[25]
  • Varnish and shellac are in effect paints without pigment; they provide a protective coating without substantially changing the color of the surface, though they can emphasise the colour of the material.
  • Wood stain is a type of paint that is formulated to be very “thin”, meaning low in viscosity, so that the pigment soaks into a material such as wood rather than remaining in a film on the surface. Stain is mainly dissolved pigment or dye plus binder material in solvent. It is designed to add color without providing a surface coating.
  • Lacquer is a solvent-based paint or varnish that produces an especially hard, durable finish. Usually it is a rapidly drying formulation.
  • Enamel paint is formulated to give an especially hard, usually glossy, finish. Some enamel paints contain fine glass powder or metal flake instead of the color pigments in standard oil-based paints. Enamel paint sometimes is mixed with varnish or urethane to improve its shine and hardness.
  • A glaze is an additive used with paint to slow drying time and increase translucency, as in faux painting and for some artistic effects.
  • A roof coating is a fluid that sets as an elastic membrane that can stretch without harm. It provides UV protection to polyurethane foam and is widely used in roof restoration.
  • Fingerpaints are formulations suitable for application with the fingers; they are popular for use by children in primary school activities.
  • Inks are similar to paints, except that they are typically made using finely ground pigments or dyes, and are not designed to leave a thick film of binder. They are used largely for writing or calligraphy.
  • Anti-graffiti coatings are used to defeat the marking of surfaces by graffiti artists or vandals. There are two categories of anti-graffiti coatings: sacrificial and non-bonding:
  • Sacrificial coatings are clear coatings that allow the removal of graffiti, usually by washing the surface with high-pressure water that removes the graffiti together with the coating (hence the term “sacrificial”). After removal of the graffiti, the sacrificial coating must be re-applied for continued protection. Such sacrificial protective coatings are most commonly used on natural-looking masonry surfaces, such as statuary and marble walls, and on rougher surfaces that are difficult to clean.
  • Non-bonding coatings are clear, high-performance coatings, usually catalyzed polyurethanes, that do not bond strongly to paints used for graffiti. Graffiti on such a surface can be removed with a solvent wash, without damaging either the underlying surface or the protective non-bonding coating. These coatings work best on smooth surfaces, and are especially useful on decorative surfaces such as mosaics or painted murals, which might be expected to suffer harm from high pressure sprays.
  • Anti-climb paint is a non-drying paint that appears normal but is extremely slippery. It is useful on drainpipes and ledges to deter burglars and vandals from climbing them, and is found in many public places. When a person attempts to climb objects coated with the paint, it rubs off onto the climber, as well as making it hard for them to climb.
  • Anti-fouling paint, or bottom paint, prevents barnacles and other marine organisms from adhering to the hulls of ships.
  • Insulative paint or insulating paint, reduces the rate of thermal transfer through a surface it’s applied to. One type of formulation is based on the addition of hollow microspheres to any suitable type of paint.
  • Anti-slip paint contains chemicals or grit to increase the friction of a surface so as to decrease the risk of slipping, particularly in wet conditions.
  • Road marking paint[26] is specially used to marking and painting road traffic signs and lines, to form a durable coating film on the road surface. It must be fast drying, provide a thick coating, and resist wear and slipping, especially in wet conditions.
  • Luminous paint or luminescent paint is paint that exhibits luminescence. In other words, it gives off visible light through fluorescence, phosphorescence, or radioluminescence.

Failure

The main reasons of paint failure after application on surface are the applicator and improper treatment of surface.

Defects or degradation can be attributed to:

Dilution
This usually occurs when the dilution of the paint is not done as per manufacturers recommendation. There can be a case of over dilution and under dilution, as well as dilution with the incorrect diluent.
Contamination
Foreign contaminants added without the manufacturers consent can cause various film defects.
Peeling/Blistering
Most commonly due to improper surface treatment before application and inherent moisture/dampness being present in the substrate. The degree of blistering can be assessed according to ISO 4628 Part 2 or ASTM Method D714 (Standard Test Method for Evaluating Degree of Blistering of Paints).
Chalking
Chalking is the progressive powdering of the paint film on the painted surface. The primary reason for the problem is polymer degradation of the paint matrix due to exposure of UV radiation in sunshine and condensation from dew. The degree of chalking varies as epoxies react quickly while acrylics and polyurethanes can remain unchanged for long periods.[27] The degree of chalking can be assessed according to International Standard ISO 4628 Part 6 or 7 or American Society of Testing and Materials(ASTM) Method D4214 (Standard Test Methods for Evaluating the Degree of Chalking of Exterior Paint Films).
Cracking
Cracking of paint film is due to the unequal expansion or contraction of paint coats. It usually happens when the coats of the paint are not allowed to cure/dry completely before the next coat is applied. The degree of cracking can be assessed according to International Standard ISO 4628 Part 4 or ASTM Method D661 (Standard Test Method for Evaluating Degree of Cracking of Exterior Paints).
Erosion
Erosion is very quick chalking. It occurs due to external agents like air, water etc. It can be evaluated using ASTM Method ASTM D662 (Standard Test Method for Evaluating Degree of Erosion of Exterior Paints). The generation of acid by fungal species can be a significant component of erosion of painted surfaces.[28] The fungus Aureobasidium pullulans is known for damaging wall paints.[29]

Dangers

Volatile organic compounds (VOCs) in paint are considered harmful to the environment and especially for people who work with them on a regular basis. Exposure to VOCs has been related to organic solvent syndrome, although this relation has been somewhat controversial.[30] The controversial solvent 2-butoxyethanol is also used in paint production.[31]

In the US, environmental regulations, consumer demand, and advances in technology led to the development of low-VOC and zero-VOC paints and finishes. These new paints are widely available and meet or exceed the old high-VOC products in performance and cost-effectiveness while having significantly less impact on human and environmental health.[citation needed]

A polychlorinated biphenyl (PCB) was reported ( published in 2009 ) in air samples collected in Chicago, Philadelphia, the Arctic, and several sites around the Great Lakes. PCB is a global pollutant and was measured in the wastewater effluent from paint production. The widespread distribution of PCB suggests volatilization of this compound from surfaces, roofs etc. PCB is present in consumer goods including newspapers, magazines, and cardboard boxes, which usually contain color pigments. Therefore, exist hypothesis that PCB congeners are present as byproduct in some current commercial pigments.[32]

See also

References

 

 

Further reading

FASHION

FASHION

Every person nurtures an innate desire of looking good and feel ‘accepted’ in the sociol-economic circle. The word fashion instantaneously brings to mind a flash of colour with a dash of glamour.

Women are taking to fashion in a big way, and are experimenting with different looks, styles, and textures.

Fashion plays an increasingly important role in an indivi­dual’s life because it is considered as a means of self-expression. The garments and accessories that man or women wear, help them to identify with a group of others-whether it is a lifestyle, profession, a religion, or an attitude. Thus, the term ‘fashion’ has become synonymous with the overall growth of the country as well.

Several factors contribute to the evolution of fashion as a whole. It is a widely accepted fact that the rich and the famous, and the political figures and royalty have always moved the seasonal trends of fashion. The advertising media also contributes equally to update us about the daily style checks.

Fashion in India, a land rich in culture and tradition, has evolved through the centuries. This country, rich in culture represents a kaleidoscope of changing trends and traditions. Here, clothes perform different functions depending on the occasion. Be it festivals, parties, profession, or just a matter of reflecting attitude … fashion is simply ‘in’.

Right from women who sport a dash of vermilion in the parting of their hair, to professionals on the go who wield the ladle and the laptop with equal ease, fashion forms an integral 92 Top School Essays

part of their lives. Today, fashion does not necessarily mean glamour, or the urge to follow the current trends. It is more a way of life, a reflection of inner beauty, where the intellect shines through, complete with comfort quotient.

Fashion not only highlights the social history and the needs of person but also the overall cultural aesthetic of the various periods. The evolution of fashion dates back to several hundred years and as our attitude and culture change, fashion comes along with it.

In India, the fashion scenario was different in different political periods. During the British rule in India, the fashion trend within high society was strongly influenced by the British fashion style and western clothes became a status symbol in India.

Again during 1930s, emergence of different ideologies like communism, socialism and fascism imparted a more feminine and conservative touch to the women’s fashion.

However, the period also witnessed the predominance of body hugging dresses with dark shades. The foundation of the Indian cinema also proved to be the strongest influence on revolutionising the fashion scene in those days.

1940s was a decade marked by the second World War and the ensuing independence of India. Hence, the period portrayed relatively simple yet functional women’s clothing.

During 1950s, the advent of art colleges and schools led to popularity of narrow waist and balloon skirts with bouncing patterns. Also, the adoption of khadi by Mahatma Gandhi made khadi garments a rage among women.

In the 1960s, the sweeping changes in fashion and lifestyle resulted in highly versatile fashion trends. In 1970s, the traditional materials were exported in bulk to other nations.

Thus, excess of export materials were sold within the country itself, which resulted in popularity of international fashion in India.

During 1980s and 90s, the advent of television and other advertising means gave a new edge to the Indian fashion scene. Influenced by ideas of several foreign designers, new design and pattern were introduced into garments.

During these periods, power dressing and corporate look were the style statement. The revival of ethnicity was also witnessed in these decades.

Fashion trends keep changing and most fashion divas and models are the one to make them. The youth is a major follower of fashion trends. Fashion trends also get influenced from Bollywood as well as Hollywood. Metros like Mumbai and Delhi witness the quick changes in fashion especially in college going crowds.

India has a rich and varied textile heritage, where each region of India has its own unique native costume and traditional attire. While traditional clothes are still worn in most of rural India, urban India is changing rapidly, with international fashion trends reflected by the young and glamorous, in the cosmopolitan metros of India.

Fashion in India is a vibrant scene, a nascent industry and a colourful and glamorous world where designers and models start new trends every day.

While previously a master weaver was recognised for his skill, today a fashion designer is celebrated for his or her creativity. Young urban Indians can choose from the best of East and West as Indian fashion designers are inspired by both Indian and western styles. This fusion of fashion can be seen

Fashion in India is also beginning to make its mark on the international scene, as accessories such as bindis (red dots worn on the forehead), mehendi (designs made by applying henna to the palms of the hands and other parts of the body) and bangles, have gained international popularity, after being worn by fashion icons, like the pop singers Madonna and Gwen Stefani.

In India, fashion has become a growing industry with international events such as the India Fashion Week and annual shows by fashion designers in the major cities of India.

The victories of a number of Indian beauty queens in International events such as the Miss World and Miss Universe contests have also made Indian models recognised worldwide.

Fashion designers such as Ritu Kumar, Ritu Beri, Rohit Bal, Rina Dhaka, Muzaffar Ah, Satya Paul, Abraham and Thakore, Tarun Tahiliani, JJ Valaya and Manish Malhotra are some of the well- known fashion designers in India.

In India, fashion covers a whole range of clothing from ornate clothes designed for wedding ceremonies to pret lines, sports wear and casual wear.

Traditional Indian techniques of embroidery such as chikhan, crewel and zardosi, and traditional weaves and fabrics have been used by Indian designers to create Indo-western clothing in a fusion of the best of East and West.

Traditional costumes in India vary widely depending on the climate and natural fibres grown in a region. In the cold northern state of Jammu and Kashmir, people wear a thick loose shirt called a phiran to keep them warm.

In the tropical warmth of south India, men wear a sarong like garment called the mundu, while women drape 5 metres of cloth around their bodies in the graceful folds of the saree. Sarees are woven in silk, cotton and artificial fibres. Kanjivaram, Mysore, Paithani, Pochampalli, Jamdani, Balucheri, Benarasi, Sambalpuri,

Bandhini are some varieties of beautiful sarees from different regions of India. In the dry regions of Rajasthan and Gujarat men wrap and twist a length of cloth in the form of a dhoti around their lower limbs and a shirt-like kurta above.

Colourful turbans complete the picture. In the northeastern regions the tribal communities such as Khasis, Nagas, Mizos, Manipuris and Arunachalis wear colourful woven sarong-like clothing and woven shawls that represent the identity of each tribal group.

In urban India the salwar kameez and the churidar kameez, are commonly work by women and the saree is worn on formal occasions. Men wear kurtas and pajamas, or a sherwani for formal wear. Men commonly wear western wear such as shirts and trousers across India.

The young and the young at heart wear Jeans, T-shirts, capris, Bermudas and various kinds of casual clothing, which are the trendsetters of fashion in India.

Comparing the past and the present, fashion for people in India has changed over the decades. Not only India, but also the whole world has witnessed changes in fashion statements for both men and women.

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STORY

STORY

Your business is in deep mud. Not just metaphorically speaking, but for real. The building’s very foundations have started sinking in slime. Best case scenario: your contractor actually takes responsibility for the mess and doesn’t evaporate into thin air, but he is still at a loss. Yes, he has heard about such cases, but has no idea what to do about it. He knows how to construct buildings, but has no idea how to pull them out of the mud. He tries to joke about it, but you are hardly in the mood.

You start sustaining losses. One thing’s for sure: you haven’t much time. You must decide quickly. You wake up each morning and go through the few options you have left. Actually, the option of letting the entire building sink into the mud sounds rather attractive this morning. What the , the entire area seems to lie on one big bog. In fact, you have seen endless neighboring buildings come down, so what on earth made you think it couldn’t happen to you? But that inner voice of yours doesn’t let you give up. Not just yet, anyway.

The second option is to let that huge contractor company help you. After all they are a brand name. They sell. They have spacious offices. Their sales rep has already met with you once. He parked his shiny car far away, careful not to soil it with mud. Throughout your conversation – if his sales pitch could be termed as such – you couldn’t but notice the effort you were making to believe him. To really and truly believe, that is. “The best workers in the business,” he said. “Committed to the highest standards in a variety of technologies,” he added. At some point he even emitted, “a company based on values, in which the client is part of the family.”

it. If only you were one of those people who let sales people sweep them off their feet, you might actually be happy. But unfortunately for you, you are not one of those people. You are one of those miserables who need only take one look at a person and know straight away that “this person hasn’t the faintest idea what he is talking about.”

This morning the situation is somewhat different. “Sustaining losses” no longer describes the problem sufficiently and when the bank manager calls she no longer sounds accommodating. So it’s safe to say you have understood the situation, right? Not a good one. Actually, pretty bad, is more like it.

You heard about that little company quite some time ago. In fact, you heard about it from a number of sources, but you have never really spoken to them. Why? Mainly because you prefer working with big companies. On any other day you would be the first to explain to anyone willing to listen why working with a boutique company isn’t suitable for a company of your scale. However, at this very moment, one of your load-bearing walls appears to be on the verge of collapse.

When you dial the number, sweat pours down your back, and you try to convince yourself that this cannot be the last resort, but your fingers are crossed when you hear the dial tone, and inside you are praying: Let it work! Let it work!

The very next day the manager himself shows up on a bike and parks it really close by. Right in the middle of all the mud.

You say hello and start relating the building’s history.

“Okay, gotcha,” he cuts you off after a minute. “Let’s just go inside and see what things are like,” he says calmly. He is the first one to ask to come in.

You try leading him, but he soon overtakes you and disappears into the innermost rooms. Never before in your life have you seen somebody who seems to know his way around your dilapidated building and in no time. After a while he comes back.

“So what do you think?” you venture. You would usually also add, “And don’t make it prettier than it is,” but with this guy you feel there is no need. He is not going to beat around the bush with you.

“Listen, things are pretty up here,” he says without a trace of humor while looking at the load-bearing wall. He knocks on it and half the coating peels off. “I’ve seen worse,” he adds, and by his look you know he is not lying. After a few seconds he says, “Okay, we will take on the job.”

He is so crazily self-confident – a trait belonging either to charlatans or to the very best professionals, you wonder to yourself – that you realize it is up to you to decide whether the guy standing before you is the former or latter.

“Just a moment,” you suddenly take fright, “how much will it cost?”

While he is busy jotting down numbers, you pray that it won’t be expensive. They are a small company after all, so please let it be cheap. He shows you the figure and your stomach does summersaults. He doesn’t wait for you to react, but continues: “We are really good,” and smiles for the first time. Suddenly you realize that the son-of-a- really loves his job. “We will begin tomorrow,” he says, “There is no time to lose. I am going to prepare the work plans. Be by us at 8:00 sharp. Don’t be late.“

You are in a complete daze but somehow manage to say something like, “Oh, okay, yeah sure, I won’t be late. See you in the morning” and he turns around and leaves.

After a few minutes, when you come out of your trance, you feel like shouting after him that you don’t really need him and who the does he think he is and that it’s better working with the big companies. Because they have a standard of values, that is – their values are a standard, that is the best workers in the market are their family, in other words – never mind – they have spacious offices!

True, you must admit to yourself, their clientele list is far more impressive than that of any other company you have heard of, and yet… And yet…

At the end you take a deep breath. And another one. And then you feel something strange. And you ask yourself whether it’s that headache again, caused by the pressure you have been feeling for the past months, but it’s not that. Or perhaps it’s those stomach cramps caused by the fear that everything might soon come to an end? But it isn’t that either.

You haven’t felt like this in a long time, but by now you know exactly what it is you are feeling, although you are still too embarrassed to admit it to yourself. So your inner voice says it out loud for you: You are simply – calm.

Your business is in deep mud. The entire building has started sinking. Not really, only metaphorically speaking.

 

THE GREAT GARBAGE PATCH

 

The Great Pacific garbage patch, also described as the Pacific trash vortex, is a gyre of marine debris particles in the central North Pacific Ocean discovered between 1985 and 1988. It is located roughly between 135°W to 155°W and 35°N to 42°N.[1] The collection of plastic, floating trash halfway between Hawaii and California[2] extends over an indeterminate area of widely varying range depending on the degree of plastic concentration used to define the affected area.

The patch is characterized by exceptionally high relative pelagic concentrations of plastic, chemical sludge, and other debris that have been trapped by the currents of the North Pacific Gyre.[3] Despite the common public image of islands of floating rubbish, its low density (4 particles per cubic meter) prevents detection by satellite imagery, or even by casual boaters or divers in the area. It consists primarily of an increase in suspended, often microscopic, particles in the upper water column.

The Great Pacific garbage patch was described in a 1988 paper published by the National Oceanic and Atmospheric Administration (NOAA) of the United States. The description was based on results obtained by several Alaska-based researchers in 1988 that measured neustonic plastic in the North Pacific Ocean.[4] Researchers found relatively high concentrations of marine debris accumulating in regions governed by ocean currents. Extrapolating from findings in the Sea of Japan, the researchers hypothesized that similar conditions would occur in other parts of the Pacific where prevailing currents were favorable to the creation of relatively stable waters. They specifically indicated the North Pacific Gyre.[5]

Charles J. Moore, returning home through the North Pacific Gyre after competing in the Transpacific Yacht Race in 1997, claimed to have come upon an enormous stretch of floating debris. Moore alerted the oceanographer Curtis Ebbesmeyer, who subsequently dubbed the region the “Eastern Garbage Patch” (EGP).[6] The area is frequently featured in media reports as an exceptional example of marine pollution.[7]

The Pacific garbage patch is not easily seen from the sky, because the plastic is dispersed over a large area. Researchers from The Ocean Cleanup have found the patch to cover an area of 1.6 million square kilometers. The plastic concentration is estimated to be up to 100 kilograms per square kilometer in the center of the patch, going down to 10 kilograms per square kilometer in the outer parts of the patch. There is an estimate of 80,000 metric tons of plastic in the patch, totalling 1.8 trillion pieces. When accounting for the total mass, 92% of the debris found in the patch consists of objects larger than 0.5 centimeters. [8]

A similar patch of floating plastic debris is found in the Atlantic Ocean, called the North Atlantic garbage patch.

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