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http://www.bennettsmilitary.net/Sells clothing, knives and swords, camping and survival gear, backpacks and luggage, and footwear. clothing 衣服Clothing or clothes protect the human body from extreme weather and other features of the environment. It is worn for safety, comfort, modesty and to reflect religious, cultural and social meaning.
The practical function of clothing is to protect the human body from dangers in the environment: weather (strong sunlight, extreme heat or cold, and precipitation, for example), insects, noxious chemicals, weapons, and contact with abrasive substances, and other hazards. Clothing can protect against many things that might injure the naked human body. In some cases, clothing protects the environment from the clothing wearer as well (example: medical scrubs).
Humans have shown extreme inventiveness in devising clothing solutions to practical problems and the distinction between clothing and other protective equipment is not always clear-cut; examples include space suit, air conditioned clothing, armor, diving suit, swimsuit, bee-keeper's protective clothing, motorcycle leathers, high-visibility clothing, and protective clothing.
People also decorate their bodies with makeup or cosmetics, scented perfume, and other ornamentation; they also cut, dye, and arrange the hair on their heads, faces, and bodies (see hairstyle), and sometimes also mark their skin (by tattoos, scarifications, and piercings). All these decorations may contribute to the overall effect and message of clothing, but do not constitute clothing.
Articles carried rather than worn (such as purses, canes, and umbrellas) are normally considered fashion accessories rather than clothing, but hats and small dress sweaters can be called clothing or accessories.[citation needed] Jewelry and eyeglasses are usually considered as accessories as well, even though in common speech these particular items are described as being worn rather than carried.
Historically, there have been many societies where partial or complete nudity was the cultural norm. In the modern world, most cultures find it socially unacceptable to walk around in public without clothes.
According to archaeologists and anthropologists, the earliest clothing probably consisted of fur, leather, leaves or grass, draped, wrapped or tied about the body for protection from the elements. Knowledge of such clothing remains inferential, since clothing materials deteriorate quickly compared to stone, bone, shell and metal artifacts. Archeologists have identified very early sewing needles of bone and ivory from about 30,000 BC, found near Kostenki, Russia in 1988.[citation needed]
Ralf Kittler, Manfred Kayser and Mark Stoneking, anthropologists at the Max Planck Institute for Evolutionary Anthropology, have conducted a genetic analysis of human body lice that indicates that they originated about 107,000 years ago. Since most humans have very sparse body hair, body lice require clothing to survive, so this suggests a surprisingly recent date for the invention of clothing. Its invention may have coincided with the spread of modern Homo sapiens from the warm climate of Africa, thought to have begun between 50,000 and 100,000 years ago. However, a second group of researchers used similar genetic methods to estimate that body lice originated about 540,000 years ago (Reed et al. 2004. PLoS Biology 2(11): e340). For now, the date of the origin of clothing remains unresolved.
Some human cultures, such as the various peoples of the Arctic Circle, until recently made their clothing entirely of prepared and decorated furs and skins. Other cultures have supplemented or replaced leather and skins with cloth: woven, knitted, or twined from various animal and vegetable fibers.
■眼精疲労 サプリ 眼精疲労疾患を和らげるサプリメントをご紹介! knives ナイフA knife is a handheld sharp-edged instrument consisting of handle attached to a blade used for cutting. The knife is a tool that can be used as a weapon. Its origins date as far back as two-and-a-half million years ago, as evidenced by the Oldowan tools. The earliest knives were shaped by knapping (percussive flaking) of rock, particularly harder rocks such as obsidian and flint. During the Paleolithic era Homo habilis likely made similar tools out of wood, bone, and similar highly perishable materials that have not survived. As recent as five thousand years ago, as advances in metallurgy progressed, stone, wood, and bone blades were gradually succeeded by copper, bronze, iron, and eventually steel. The first metal (copper) knives were symmetrical double edged daggers, which copied the earlier flint daggers. In Europe the first single edged knives appeared during the middle bronze age. These replaced daggers, which by that time had evolved into swords. Modern knives may be made from many different materials such as alloy tool steels, carbon fiber, ceramics, and titanium.There is a very active community of modern custom knife makers and collectors, who often pioneer the use of new materials in knives. In the United States, The American Bladesmith Society promotes forged blades; the Knifemakers Guild promotes all custom knives.
Knife blades can be manufactured from a variety of materials, each of which has advantages and disadvantages. Carbon steel, an alloy of iron and carbon, can be very sharp, hold its edge well, and remain easy to sharpen, but is vulnerable to rust and stains. Stainless steel is an alloy of iron, chromium, possibly nickel, and molybdenum, with only a small amount of carbon. It is not able to take quite as sharp an edge as carbon steel, but is highly resistant to corrosion. High carbon stainless steel is stainless steel with a higher amount of carbon, intended to combine the best attributes of carbon steel and stainless steel. High carbon stainless steel blades do not discolor or stain, and maintain a sharp edge. Laminate blades use multiple metals to create a layered sandwich, combining the attributes of both. For example, a harder, more brittle steel may be sandwiched between an outer layer of softer, tougher, stainless steel to reduce vulnerability to corrosion. In this case, however, the part most affected by corrosion, the edge, is still vulnerable. Pattern-welding is similar to laminate construction. Layers of different steel types are welded together, but then the stock is manipulated to create patterns in the steel. Titanium is metal that is lighter, more wear resistant, and more flexible than steel. Although less hard and unable to take as sharp an edge, carbides in the titanium alloy allow them to be heat-treated to a sufficient hardness. Ceramic blades are incredibly hard, lightweight blades; so hard that they will maintain a sharp edge for months or years with no maintenance at all. They are immune to corrosion, but can only be sharpened on silicon carbide sandpaper and some grinding wheels. Plastic blades are not very sharp at all but are typically serrated, and are usually considered disposable.
from wikipedia |