Plastic is material consisting of any of a wide range of synthetic or semi-synthetic organic compounds that are malleable and so can be molded into solid objects. Plasticity is the general property of all materials which can deform irreversibly without breaking but, in the class of moldable polymers, this occurs to such a degree that their actual name derives from this specific ability. Plastics are organic polymers of high molecular mass and contain other substances, they are synthetic, most derived from petrochemicals, however, an array of variants are made from renewable materials such as polylactic acid from corn or cellulosics from cotton linters. Due to their low cost, ease of manufacture and imperviousness to water, plastics are used in a multitude of products of different scale, including paper clips and spacecraft, they have prevailed over traditional materials, such as wood, stone and bone, metal and ceramic, in some products left to natural materials. In developed economies, about a third of plastic is used in packaging and the same in buildings in applications such as piping, plumbing or vinyl siding.
Other uses include automobiles and toys. In the developing world, the applications of plastic may differ—42% of India's consumption is used in packaging. Plastics have many uses in the medical field as well, with the introduction of polymer implants and other medical devices derived at least from plastic; the field of plastic surgery is not named for use of plastic materials, but rather the meaning of the word plasticity, with regard to the reshaping of flesh. The world's first synthetic plastic was bakelite, invented in New York in 1907 by Leo Baekeland who coined the term'plastics'. Many chemists have contributed to the materials science of plastics, including Nobel laureate Hermann Staudinger, called "the father of polymer chemistry" and Herman Mark, known as "the father of polymer physics"; the success and dominance of plastics starting in the early 20th century led to environmental concerns regarding its slow decomposition rate after being discarded as trash due to its composition of large molecules.
Toward the end of the century, one approach to this problem was met with wide efforts toward recycling. The word plastic derives from the Greek πλαστικός meaning "capable of being shaped or molded" and, in turn, from πλαστός meaning "molded"; the plasticity, or malleability, of the material during manufacture allows it to be cast, pressed, or extruded into a variety of shapes, such as: films, plates, bottles, amongst many others. The common noun plastic should not be confused with the technical adjective plastic; the adjective is applicable to any material which undergoes a plastic deformation, or permanent change of shape, when strained beyond a certain point. For example, aluminum, stamped or forged exhibits plasticity in this sense, but is not plastic in the common sense. By contrast, some plastics will, in their finished forms, break before deforming and therefore are not plastic in the technical sense. Most plastics contain organic polymers; the vast majority of these polymers are formed from chains of carbon atoms,'pure' or with the addition of: oxygen, nitrogen, or sulfur.
The chains comprise many repeat units, formed from monomers. Each polymer chain will have several thousand repeating units; the backbone is the part of the chain, on the "main path", linking together a large number of repeat units. To customize the properties of a plastic, different molecular groups "hang" from this backbone; these pendant units are "hung" on the monomers, before the monomers themselves are linked together to form the polymer chain. It is the structure of these side chains; the molecular structure of the repeating unit can be fine tuned to influence specific properties in the polymer. Plastics are classified by: the chemical structure of the polymer's backbone and side chains. Plastics can be classified by: the chemical process used in their synthesis, such as: condensation and cross-linking. Plastics can be classified by: their various physical properties, such as: hardness, tensile strength, resistance to heat and glass transition temperature, by their chemical properties, such as the organic chemistry of the polymer and its resistance and reaction to various chemical products and processes, such as: organic solvents and ionizing radiation.
In particular, most plastics will melt upon heating to a few hundred degrees celsius. Other classifications are based on qualities that are relevant for product design. Examples of such qualities and classes are: thermoplastics and thermosets, conductive polymers, biodegradable plastics and engineering plastics and other plastics with particular structures, such as elastomers. One important classification of plastics is by the permanence or impermanence of their form, or whether they are: thermoplastics or thermosetting polymers. Thermoplastics are the plastics that, when heated, do not undergo chemical change in their composition and so can be molded again and again. Examples include: polyethylene, polypropylene and polyvinyl chloride. Common thermoplastics range from 20,000 to 500,000 amu, while thermosets are assumed to have infinite molecular weight. Thermosets, or thermosetting polymers, can melt and take shape only once: after they have solidified, they stay solid. In the thermosetting process, a chemical reaction occurs, irreversible.
Sterling State Park
William C. Sterling State Park is a state park located in Frenchtown Charter Township and a smaller portion in the city limits of Monroe, Michigan, it is the only Michigan state park located on Lake Erie. The park encompasses 2.03 mi² of man-made lagoons and beachfront near the mouth of Sandy Creek. The main attractions at the park include the 256-site campground, beach area, a public boat launch, shore fishing lagoons. There are over six miles of hiking trails within the park; the park is named for William Clark Sterling, a businessman and outdoorsman who bought marshland at the mouth of the Detroit River and was one of the first to see the value in protecting swamps for future generations and the good of the environment. The state acquired the park's first 134 acres—a narrow strip lying between Lake Erie and a lagoon—in 1935. A portion of the land had been donated by the city of Monroe and the Monroe Piers Land Company, which had once been owned by Sterling; the park was dedicated the following year.
For quite some time, Sterling State Park was polluted by river runoff from Detroit, swimming in the water was not recommended and illegal. In an effort to preserve the Lake Erie coastline after decades of pollutants from the Detroit River emptied into the region—killing off tremendous amounts of wildlife and leaving the lake uninhabitable—millions of dollars were spent and the region was cleaned up and restored. In the late 1990s, the Environmental Protection Agency declared the area to be an environmental concern due to the level of pollutants in Lake Erie and the River Raisin; when studying fish in the area, PCB levels increased 87% from the 1988 to 1998. The result of the overpollution came from the sudden industrial growth surrounding the River Raisin delta and Lake Erie; the largest of these industries include a Ford plant and the coal-burning Monroe Power Plant, both of which caused severe impacts on the ecosystem of the area. In September 1997, the Ford completed an environmental dredging project in the River Raisin and removed 25,000 cubic yards of toxic PCB-contaminated sediment from the River Raisin.
In 2001, William C. Sterling State Park was included as the southern border of the Detroit River International Wildlife Refuge; this allowed the park to receive federal funding for a $12 million renovation project. The park was closed during the 2003 season while the renovation was carried out to the park, remodeled to include miles of wetland walking paths open to the public in an area, closed since the early 1900s. Today, the park boasts many lagoons and marshes, providing good habitat for a variety of wildlife and bird life that have returned to the area. During the time of renovation, there was a threat of E. coli bacteria in the lake waters, which resulted in several deaths in neighboring Ontario. William C. Sterling State Park was not tested. Swimming in Lake Erie is monitored to make sure that the level of toxins are low enough not to pose a threat to human safety; the once polluted lake has undergone much restoration in the past decade, which has benefited William C. Sterling State Park.
Today, William C. Sterling State Park includes 256 modernized camp sites, picnic areas and shelters and hiking trails, a recreational metal detecting area, beach access, playgrounds. Snowmobiling is permitted in the park; the park is bordered by a pristine 36-hole golf course. Every year for Independence Day, Monroe holds a fireworks show on Lake Erie, within clear view of the park, to which thousands of people drive to view the show, causing severe traffic congestion. Many boats moor on the lake, where the fireworks are best seen. Sterling State Park Michigan Department of Natural Resources Sterling State Park Map Michigan Department of Natural Resources Sterling State Park Protected Planet
The domestic dog is a member of the genus Canis, which forms part of the wolf-like canids, is the most abundant terrestrial carnivore. The dog and the extant gray wolf are sister taxa as modern wolves are not related to the wolves that were first domesticated, which implies that the direct ancestor of the dog is extinct; the dog was the first species to be domesticated and has been selectively bred over millennia for various behaviors, sensory capabilities, physical attributes. Their long association with humans has led dogs to be uniquely attuned to human behavior and they are able to thrive on a starch-rich diet that would be inadequate for other canid species. Dogs vary in shape and colors, they perform many roles for humans, such as hunting, pulling loads, assisting police and military, companionship and, more aiding disabled people and therapeutic roles. This influence on human society has given them the sobriquet of "man's best friend"; the term dog is applied both to the species as a whole, any adult male member of the same.
An adult female is a bitch. An adult male capable of reproduction is a stud. An adult female capable of reproduction is brood mother. Immature males or females are puppies. A group of pups from the same gestation period is called a litter; the father of a litter is a sire. It is possible for one litter to have multiple sires; the mother of a litter is a dam. A group of any three or more adults is a pack. In 1999, a study of mitochondrial DNA indicated that the domestic dog may have originated from multiple grey wolf populations, with the dingo and New Guinea singing dog "breeds" having developed at a time when human populations were more isolated from each other. In the third edition of Mammal Species of the World published in 2005, the mammalogist W. Christopher Wozencraft listed under the wolf Canis lupus its wild subspecies, proposed two additional subspecies: "familiaris Linneaus, 1758 " and "dingo Meyer, 1793 ". Wozencraft included hallstromi – the New Guinea singing dog – as a taxonomic synonym for the dingo.
Wozencraft referred to the mDNA study as one of the guides in forming his decision. The inclusion of familiaris and dingo under a "domestic dog" clade has been noted by other mammalogists; this classification by Wozencraft is debated among zoologists. The origin of the domestic dog includes the dog's evolutionary divergence from the wolf, its domestication, its development into dog types and dog breeds; the dog is a member of the genus Canis, which forms part of the wolf-like canids, was the first species and the only large carnivore to have been domesticated. The dog and the extant gray wolf are sister taxa, as modern wolves are not related to the population of wolves, first domesticated; the genetic divergence between dogs and wolves occurred between 40,000–20,000 years ago, just before or during the Last Glacial Maximum. This timespan represents the upper time-limit for the commencement of domestication because it is the time of divergence and not the time of domestication, which occurred later.
The domestication of animals commenced over 15,000 years ago, beginning with the grey wolf by nomadic hunter-gatherers. The archaeological record and genetic analysis show the remains of the Bonn–Oberkassel dog buried beside humans 14,200 years ago to be the first undisputed dog, with disputed remains occurring 36,000 years ago, it was not until 11,000 years ago that people living in the Near East entered into relationships with wild populations of aurochs, boar and goats. Where the domestication of the dog took place remains debated, with the most plausible proposals spanning Western Europe, Central Asia and East Asia; this has been made more complicated by the recent proposal that an initial wolf population split into East and West Eurasian groups. These two groups, before going extinct, were domesticated independently into two distinct dog populations between 14,000 and 6,400 years ago; the Western Eurasian dog population was and replaced by East Asian dogs introduced by humans at least 6,400 years ago.
This proposal is debated. Domestic dogs have been selectively bred for millennia for various behaviors, sensory capabilities, physical attributes. Modern dog breeds show more variation in size and behavior than any other domestic animal. Dogs are predators and scavengers, like many other predatory mammals, the dog has powerful muscles, fused wrist bones, a cardiovascular system that supports both sprinting and endurance, teeth for catching and tearing. Dogs are variable in height and weight; the smallest known adult dog was a Yorkshire Terrier, that stood only 6.3 cm at the shoulder, 9.5 cm in length along the head-and-body, weighed only 113 grams. The largest known dog was an English Mastiff which weighed 155.6 kg and was 250 cm from the snout to the tail. The tallest dog is a Great Dane; the dog's senses include vision, sense of smell, sense of taste and sensitivity to the earth's magnetic field. Another study suggested; the coats of domestic dogs are of two varieties: "double" being common with dogs originating from colder climates, made up of a coarse guard hair and a soft down hair, or "single", with the topcoat only.
Breeds may have stripe, or "star" of white fur on their chest or underside. Regarding coat appearance or h
A glove is a garment covering the whole hand. Gloves have separate sheaths or openings for each finger and the thumb. If there is an opening but no covering sheath for each finger they are called fingerless gloves. Fingerless gloves having one large opening rather than individual openings for each finger are sometimes called gauntlets, though gauntlets are not fingerless. Gloves which cover the entire hand or fist but do not have separate finger openings or sheaths are called mittens. Mittens are warmer than other styles of gloves made of the same material because fingers maintain their warmth better when they are in contact with each other. A hybrid of glove and mitten contains open-ended sheaths for the four fingers and an additional compartment encapsulating the four fingers; this compartment can be lifted off the fingers and folded back to allow the individual fingers ease of movement and access while the hand remains covered. The usual design is for the mitten cavity to be stitched onto the back of the fingerless glove only, allowing it to be flipped over to transform the garment from a mitten to a glove.
These hybrids are called convertible mittens or glittens, a combination of "glove" and "mittens". Gloves protect and comfort hands against cold or heat, damage by friction, abrasion or chemicals, disease. Latex, nitrile rubber or vinyl disposable gloves are worn by health care professionals as hygiene and contamination protection measures. Police officers wear them to work in crime scenes to prevent destroying evidence in the scene. Many criminals wear gloves to avoid leaving fingerprints, which makes the crime investigation more difficult. However, the gloves themselves can leave prints that are just as unique as human fingerprints. After collecting glove prints, law enforcement can match them to gloves that they have collected as evidence. In many jurisdictions the act of wearing gloves itself while committing a crime can be prosecuted as an inchoate offense. Fingerless gloves are useful where dexterity is required that gloves would restrict. Cigarette smokers and church organists use fingerless gloves.
Some gloves include a gauntlet that extends partway up the arm. Cycling gloves for road racing or touring are fingerless. Guitar players use fingerless gloves in circumstances where it is too cold to play with an uncovered hand. Gloves are made of materials including cloth, knitted or felted wool, rubber, neoprene and metal. Gloves of kevlar protect the wearer from cuts. Gloves and gauntlets are integral components of pressure suits and spacesuits such as the Apollo/Skylab A7L which went to the moon. Spacesuit gloves combine toughness and environmental protection with a degree of sensitivity and flexibility. Gloves appear to be of great antiquity. According to some translations of Homer's The Odyssey, Laërtes is described as wearing gloves while walking in his garden so as to avoid the brambles. Herodotus, in The History of Herodotus, tells how Leotychides was incriminated by a glove full of silver that he received as a bribe. There are occasional references to the use of gloves among the Romans as well.
Pliny the Younger, his uncle's shorthand writer wore gloves in winter so as not to impede the elder Pliny's work. A gauntlet, which could be a glove made of leather or some kind of metal armour, was a strategic part of a soldier's defense throughout the Middle Ages, but the advent of firearms made hand-to-hand combat rare; as a result, the need for gauntlets disappeared. During the 13th century, gloves began to be worn by ladies as a fashion ornament, they were made of linen and silk, sometimes reached to the elbow. Such worldly accoutrements were not for holy women, according to the early 13th century Ancrene Wisse, written for their guidance. Sumptuary laws were promulgated to restrain this vanity: against samite gloves in Bologna, 1294, against perfumed gloves in Rome, 1560. A Paris corporation or guild of glovers existed from the thirteenth century, they made them in skin or in fur. By 1440, in England glovers had become members of the Dubbers or Bookbinders Guild until they formed their own guild during the reign of Elizabeth I.
The Glovers' Company was incorporated in 1613. It was not until the 16th century that gloves reached their greatest elaboration; the 1592 "Ditchley" portrait of her features her holding leather gloves in her left hand. In Paris, the gantiers became gantiers parfumeurs, for the scented oils, musk and civet, that perfumed leather gloves, but their trade, an introduction at the court of Catherine de Medici, was not recognised until 1656, in a royal brevet. Makers of knitted gloves, which did not retain perfume and had less social cachet, were organised in a separate guild, of bonnetiers who might knit silk as well as wool; such workers were organised in the fourteenth century. Knitted gloves were a refined handiwork that required five years of apprenticeship. In the 17th century, gloves made of soft chicken skin became fashionable; the craze for gloves called "limericks" took hold. This particular fad was the product of a manufacturer in Limerick, who fashioned the gloves from the sk