|
Pastel Do Lorvão
A pastel () is an art medium that consists of powdered pigment and a binder. It can exist in a variety of forms, including a stick, a square, a pebble, and a pan of color, among other forms. The pigments used in pastels are similar to those used to produce some other colored visual arts media, such as oil paints; the binder is of a neutral hue and low saturation. The color effect of pastels is closer to the natural dry pigments than that of any other process. Pastels have been used by artists since the Renaissance, and gained considerable popularity in the 18th century, when a number of notable artists made pastel their primary medium. An artwork made using pastels is called a pastel (or a pastel drawing or pastel painting). ''Pastel'' used as a verb means to produce an artwork with pastels; as an adjective it means pale in color. Pastel media Pastel sticks or crayons consist of powdered pigment combined with a binder. The exact composition and characteristics of an individu ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Flowers In A Green Vase By Leon Dabo
Flowers, also known as blooms and blossoms, are the reproductive structures of flowering plants (angiosperms). Typically, they are structured in four circular levels, called whorls, around the end of a stalk. These whorls include: calyx, modified leaves; corolla, the petals; androecium, the male reproductive unit consisting of stamens and pollen; and gynoecium, the female part, containing style and stigma, which receives the pollen at the tip of the style, and ovary, which contains the ovules. When flowers are arranged in groups, they are known collectively as inflorescences. Floral growth originates at stem tips and is controlled by MADS-box genes. In most plant species flowers are heterosporous, and so can produce sex cells of both sexes. Pollination mediates the transport of pollen to the ovules in the ovaries, to facilitate sexual reproduction. It can occur between different plants, as in cross-pollination, or between flowers on the same plant or even the same flower ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Polyethylene Glycol
Polyethylene glycol (PEG; ) is a polyether compound derived from petroleum with many applications, from industrial manufacturing to medicine. PEG is also known as polyethylene oxide (PEO) or polyoxyethylene (POE), depending on its molecular weight. The structure of PEG is commonly expressed as H−(O−CH2−CH2)n−OH. PEG is commonly incorporated into hydrogels which present a functional form for further use. Uses Medical uses * Pharmaceutical-grade PEG is used as an excipient in many pharmaceutical products, in oral, topical, and parenteral dosage forms. * PEG is the basis of a number of laxatives (as ''MiraLax, RestoraLAX, MoviPrep, etc.''). Whole bowel irrigation with polyethylene glycol and added electrolytes is used for bowel preparation before surgery or colonoscopy or for children with constipation. Macrogol (with brand names such as Laxido, Movicol and Miralax) is the generic name for polyethylene glycol used as a laxative. The name may be followed by a number th ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Static Electricity
Static electricity is an imbalance of electric charges within or on the surface of a material. The charge remains until it can move away by an electric current or electrical discharge. The word "static" is used to differentiate it from electric current, current electricity, where an electric charge flows through an electrical conductor. A static electric charge can be created whenever two surfaces contact and/or slide against each other and then separate. The effects of static electricity are familiar to most people because they can feel, hear, and even see sparks if the excess charge is neutralized when brought close to an electrical conductor (for example, a path to ground), or a region with an excess charge of the opposite polarity (positive or negative). The familiar phenomenon of a static shockmore specifically, an electrostatic dischargeis caused by the neutralization of a charge. Causes Materials are made of atoms that are normally electrically neutral because they contai ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Poly(methyl Methacrylate)
Poly(methyl methacrylate) (PMMA) is a synthetic polymer derived from methyl methacrylate. It is a transparent thermoplastic, used as an engineering plastic. PMMA is also known as acrylic, acrylic glass, as well as by the trade names and brands Crylux, Walcast, Hesalite, Plexiglas, Acrylite, Lucite, PerClax, and Perspex, among several others ( see below). This plastic is often used in sheet form as a lightweight or shatter-resistant alternative to glass. It can also be used as a casting resin, in inks and coatings, and for many other purposes. It is often technically classified as a type of glass, in that it is a non-crystalline vitreous substance—hence its occasional historic designation as ''acrylic glass''. History The first acrylic acid was created in 1843. Methacrylic acid, derived from acrylic acid, was formulated in 1865. The reaction between methacrylic acid and methanol results in the ester methyl methacrylate. It was developed in 1928 in several different la ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Gouache
Gouache (; ), body color, or opaque watercolor is a water-medium paint consisting of natural pigment, water, a binding agent (usually gum arabic or dextrin), and sometimes additional inert material. Gouache is designed to be opaque. Gouache has a long history, having been used for at least twelve centuries. It is used most consistently by commercial artists for posters, illustrations, comics, and other design work. Gouache is similar to watercolor in that it can be rewetted and dried to a matte finish, and the paint can become infused into its paper support. It is similar to acrylic or oil paints in that it is normally used in an opaque painting style and it can form a superficial layer. Many manufacturers of watercolor paints also produce gouache, and the two can easily be used together. Description Gouache paint is similar to watercolor, but it is modified to make it opaque. Just as in watercolor, the binding agent has traditionally been gum arabic but since the la ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Scenery Painter Schlosspark Charlottenburg Berlin 20080423
Theatrical scenery is that which is used as a setting for a theatrical production. Scenery may be just about anything, from a single chair to an elaborately re-created street, no matter how large or how small, whether the item was custom-made or is the genuine item, appropriated for theatrical use. History The history of theatrical scenery is as old as the theatre itself, and just as obtuse and tradition bound. What we tend to think of as 'traditional scenery', i.e. two-dimensional canvas-covered ' flats' painted to resemble a three-dimensional surface or vista, is a relatively recent innovation and a significant departure from the more ancient forms of theatrical expression, which tended to rely less on the actual representation of space and more on the conveyance of action and mood. By the Shakespearean era, the occasional painted backdrop or theatrical prop was in evidence, but the show itself was written so as not to rely on such items to convey itself to the audience. However ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Rottenstone
Rotten stone, sometimes spelled as rottenstone, also known as tripoli, is fine powdered porous rock (geology), rock used as a polishing abrasive for metal smithing, historically for the grinding of optical lenses and in woodworking. It is usually weathered limestone mixed with Diatomaceous earth, diatomaceous, amorphous, or crystalline silicon dioxide, silica. It has similar applications to pumice, but it is generally sold as a finer powder and used for a more glossy polish after an initial treatment with coarser pumice powder. Tripoli particles are rounded rather than sharp, making it a milder abrasive. It is usually mixed with oil, sometimes water, and rubbed on the surface of varnished or lacquered wood with a felt pad or cloth. Rotten stone is sometimes used to buff stains out of wood. Some polishing waxes contain powdered rotten stone in a paste substrate. For larger polishing jobs, rotten stone mixed with a binder is applied to polishing wheels. It has also been used to p ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pumice
Pumice (), called pumicite in its powdered or dust form, is a volcanic rock that consists of extremely vesicular rough-textured volcanic glass, which may or may not contain crystals. It is typically light-colored. Scoria is another vesicular volcanic rock that differs from pumice in having larger vesicles, thicker vesicle walls, and being dark colored and denser.Jackson, J.A., J. Mehl, and K. Neuendorf (2005) ''Glossary of Geology'' American Geological Institute, Alexandria, Virginia. 800 pp. McPhie, J., M. Doyle, and R. Allen (1993) ''Volcanic Textures A guide to the interpretation of textures in volcanic rocks'' Centre for Ore Deposit and Exploration Studies, University of Tasmania, Hobart, Tasmania..198 pp. Pumice is created when super-heated, highly pressurized rock is rapidly ejected from a volcano. The unusual foamy configuration of pumice happens because of simultaneous rapid cooling and rapid depressurization. The depressurization creates bubbles by lowering the sol ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Laid Paper
Laid paper is a type of paper having a ribbed texture imparted by the manufacturing process. In the pre-mechanical period of European papermaking (from the 12th century into the 19th century), laid paper was the predominant kind of paper produced. Its use, however, diminished in the 19th century, when it was largely supplanted by wove paper. Laid paper is still commonly used by artists as a support for charcoal drawings. Traditional production Before the mechanization of papermaking, paper was made by hand, using a wire sieve mounted in a rectangular mould to produce a single sheet at a time. A papermaker would dip the mould into a vat containing diluted pulp of hemp or linen fibers, then lift it out, tilt it to spread the pulp evenly over the sieve and, as the water drained out between the wires, shake the mould to lock the fibers together. In the process, the pattern of the wires in the sieve was imparted to the sheet of paper. Up until the invention of wove paper around 1756, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Saturation (color Theory)
Colorfulness, chroma and saturation are attributes of perceived color relating to chromatic intensity. As defined formally by the International Commission on Illumination (CIE) they respectively describe three different aspects of chromatic intensity, but the terms are often used loosely and interchangeably in contexts where these aspects are not clearly distinguished. The precise meanings of the terms vary by what other functions they are dependent on. * Colorfulness is the "attribute of a visual perception according to which the perceived color of an area appears to be more or less chromatic (Any color that is absent of white, grey, or black)"., page 87. The colorfulness evoked by an object depends not only on its spectral reflectance but also on the strength of the illumination, and increases with the latter unless the brightness is very high ( Hunt effect). * Chroma is the "colorfulness of an area judged as a proportion of the brightness of a similarly illuminated area t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Refraction
In physics, refraction is the redirection of a wave as it passes from one transmission medium, medium to another. The redirection can be caused by the wave's change in speed or by a change in the medium. Refraction of light is the most commonly observed phenomenon, but other waves such as sound waves and Wind wave, water waves also experience refraction. How much a wave is refracted is determined by the change in wave speed and the initial direction of wave propagation relative to the direction of change in speed. Optical Prism (optics), prisms and Lens (optics), lenses use refraction to redirect light, as does the human eye. The refractive index of materials varies with the wavelength of light,R. Paschotta, article ochromatic dispersion in th, accessed on 2014-09-08 and thus the angle of the refraction also varies correspondingly. This is called dispersion (optics), dispersion and causes prism (optics), prisms and rainbows to divide white light into its constituent spectral ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
French Language
French ( or ) is a Romance languages, Romance language of the Indo-European languages, Indo-European family. Like all other Romance languages, it descended from the Vulgar Latin of the Roman Empire. French evolved from Northern Old Gallo-Romance, a descendant of the Latin spoken in Northern Gaul. Its closest relatives are the other langues d'oïl—languages historically spoken in northern France and in southern Belgium, which French (Francien language, Francien) largely supplanted. It was also substratum (linguistics), influenced by native Celtic languages of Northern Roman Gaul and by the Germanic languages, Germanic Frankish language of the post-Roman Franks, Frankish invaders. As a result of French and Belgian colonialism from the 16th century onward, it was introduced to new territories in the Americas, Africa, and Asia, and numerous French-based creole languages, most notably Haitian Creole, were established. A French-speaking person or nation may be referred to as Fra ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
