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Wood Stain
Wood stain is a type of paint used to colour wood and consists of colourants dissolved and/or suspended in a 'vehicle' or solvent. Vehicle is the preferred term, as the contents of a stain may not be truly dissolved in the vehicle, but rather suspended, and thus the vehicle may not be a true solvent. The vehicle often may be water, alcohol, a petroleum distillate, or a finishing agent such as shellac, lacquer, varnish and polyurethane. Coloured or stained finishes do not typically deeply penetrate the pores of the wood and may largely disappear when the finish deteriorates or is removed. Pigments and/or dyes are largely used as colourants in most stains. The difference between the two is in the solubility and in the size of the particles. While dyes are molecules that dissolve into the vehicle, pigments are larger than molecules and are temporarily suspended in the vehicle, usually settling out over time. Stains with primarily dye content are said to be 'transparent', while st ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Solar Radiation
Solar irradiance is the power per unit area (surface power density) received from the Sun in the form of electromagnetic radiation in the wavelength range of the measuring instrument. Solar irradiance is measured in watts per square metre (W/m2) in SI units. Solar irradiance is often integrated over a given time period in order to report the radiant energy emitted into the surrounding environment (joule per square metre, J/m2) during that time period. This integrated solar irradiance is called solar irradiation, solar exposure, solar insolation, or insolation. Irradiance may be measured in space or at the Earth's surface after atmospheric absorption and scattering. Irradiance in space is a function of distance from the Sun, the solar cycle, and cross-cycle changes.Michael Boxwell, ''Solar Electricity Handbook: A Simple, Practical Guide to Solar Energy'' (2012), p. 41–42. Irradiance on the Earth's surface additionally depends on the tilt of the measuring surface, the height ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Evaporation
Evaporation is a type of vaporization that occurs on the surface of a liquid as it changes into the gas phase. High concentration of the evaporating substance in the surrounding gas significantly slows down evaporation, such as when humidity affects rate of evaporation of water. When the molecules of the liquid collide, they transfer energy to each other based on how they collide. When a molecule near the surface absorbs enough energy to overcome the vapor pressure, it will escape and enter the surrounding air as a gas. When evaporation occurs, the energy removed from the vaporized liquid will reduce the temperature of the liquid, resulting in evaporative cooling. On average, only a fraction of the molecules in a liquid have enough heat energy to escape from the liquid. The evaporation will continue until an equilibrium is reached when the evaporation of the liquid is equal to its condensation. In an enclosed environment, a liquid will evaporate until the surrounding air is ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Moisture
Moisture is the presence of a liquid, especially water, often in trace amounts. Small amounts of water may be found, for example, in the air (humidity), in foods, and in some commercial products. Moisture also refers to the amount of water vapor present in the air. Moisture control in products Control of moisture in products can be a vital part of the process of the product. There is a substantial amount of moisture in what seems to be dry matter. Ranging in products from cornflake cereals to washing powders, moisture can play an important role in the final quality of the product. There are two main aspects of concern in moisture control in products: allowing too much moisture or too little of it. For example, adding some water to cornflake cereal, which is sold by weight, reduces costs and prevents it from tasting too dry, but adding too much water can affect the crunchiness of the cereal and the freshness because water content contributes to bacteria growth. Water content o ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Blonde
Blond (male) or blonde (female), also referred to as fair hair, is a hair color characterized by low levels of the dark pigment eumelanin. The resultant visible hue depends on various factors, but always has some yellowish color. The color can be from the very pale blond (caused by a patchy, scarce distribution of pigment) to reddish "strawberry" blond or golden-brownish ("sandy") blond colors (the latter with more eumelanin). Occasionally, the state of being blond, and specifically the occurrence of blond traits in a predominantly dark or colored population are referred to as blondism. Because hair color tends to darken with age, natural blond hair is significantly less common in adulthood. Naturally-occurring blond hair is primarily found in people living in or descended from people who lived in the northern half of Europe, and may have evolved alongside the development of light skin that enables more efficient synthesis of vitamin D, due to northern Europe's lower levels of ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Medullary Ray (botany)
Medullary rays are cellular structures found in some species of wood. They appear as radial planar structures, perpendicular to the growth rings, which are visible to the naked eye. In a transverse section they appear as radiating lines from the centre of the log. In an axial section they may appear as a variety of transverse markings, depending on how close the section is to the plane of the ray. In a tangential section they may be hard to see at all. They are formed by the activity of fascicular cambium. During the process of the division of cambium, the cambium cuts out cells on both the outer and inner side. These cells are parenchymatous. Most of these cells transform into xylem and phloem. But certain cells don't transform into xylem and phloem and remain as such. These cells cut out by the cambium towards the periphery are phloem parenchyma while those towards the pith are xylem parenchyma. Both of these cells together work as secondary medullary rays. These medullary or p ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Wood
Wood is a porous and fibrous structural tissue found in the stems and roots of trees and other woody plants. It is an organic materiala natural composite of cellulose fibers that are strong in tension and embedded in a matrix of lignin that resists compression. Wood is sometimes defined as only the secondary xylem in the stems of trees, or it is defined more broadly to include the same type of tissue elsewhere such as in the roots of trees or shrubs. In a living tree it performs a support function, enabling woody plants to grow large or to stand up by themselves. It also conveys water and nutrients between the leaves, other growing tissues, and the roots. Wood may also refer to other plant materials with comparable properties, and to material engineered from wood, or woodchips or fiber. Wood has been used for thousands of years for fuel, as a construction material, for making tools and weapons, furniture and paper. More recently it emerged as a feedstock for the productio ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Porosity
Porosity or void fraction is a measure of the void (i.e. "empty") spaces in a material, and is a fraction of the volume of voids over the total volume, between 0 and 1, or as a percentage between 0% and 100%. Strictly speaking, some tests measure the "accessible void", the total amount of void space accessible from the surface (cf. closed-cell foam). There are many ways to test porosity in a substance or part, such as industrial CT scanning. The term porosity is used in multiple fields including pharmaceutics, ceramics, metallurgy, materials, manufacturing, petrophysics, hydrology, earth sciences, soil mechanics, and engineering. Void fraction in two-phase flow In gas-liquid two-phase flow, the void fraction is defined as the fraction of the flow-channel volume that is occupied by the gas phase or, alternatively, as the fraction of the cross-sectional area of the channel that is occupied by the gas phase. Void fraction usually varies from location to location in the flow ch ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Surroundings
Surroundings are the area around a given physical or geographical point or place. The exact definition depends on the field. Surroundings can also be used in geography (when it is more precisely known as vicinity, or vicinage) and mathematics, as well as philosophy, with the literal or metaphorically extended definition. In thermodynamics, the term (and its synonym, environment) is used in a more restricted sense, meaning everything outside the thermodynamic system. Often, the simplifying assumptions are that energy and matter may move freely within the surroundings, and that the surroundings have a uniform composition. See also {{wiktionary-inline, surroundings, ambiance *Distance *Environment (biophysical) *Environment (systems) *Neighbourhood (mathematics) *Social environment *Proxemics Proxemics is the study of human use of space and the effects that population density has on behaviour, communication, and social interaction. Proxemics is one among several subcategories ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Paraffin Wax
Paraffin wax (or petroleum wax) is a soft colorless solid derived from petroleum, coal, or oil shale that consists of a mixture of hydrocarbon molecules containing between 20 and 40 carbon atoms. It is solid at room temperature and begins to melt above approximately , and its boiling point is above . Common applications for paraffin wax include lubrication, electrical insulation, and candles; dyed paraffin wax can be made into crayons. It is distinct from kerosene and other petroleum products that are sometimes called paraffin. Un-dyed, unscented paraffin candles are odorless and bluish-white. Paraffin wax was first created by Carl Reichenbach in Germany in 1830 and marked a major advancement in candlemaking technology, as it burned more cleanly and reliably than tallow candles and was cheaper to produce. In chemistry, ''paraffin'' is used synonymously with ''alkane'', indicating hydrocarbons with the general formula C''n''H2''n''+2. The name is derived from Latin ''parum'' (" ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Insects
Insects (from Latin ') are pancrustacean hexapod invertebrates of the class Insecta. They are the largest group within the arthropod phylum. Insects have a chitinous exoskeleton, a three-part body (head, thorax and abdomen), three pairs of jointed legs, compound eyes and one pair of antennae. Their blood is not totally contained in vessels; some circulates in an open cavity known as the haemocoel. Insects are the most diverse group of animals; they include more than a million described species and represent more than half of all known living organisms. The total number of extant species is estimated at between six and ten million; In: potentially over 90% of the animal life forms on Earth are insects. Insects may be found in nearly all environments, although only a small number of species reside in the oceans, which are dominated by another arthropod group, crustaceans, which recent research has indicated insects are nested within. Nearly all insects hatch from eggs. Inse ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mildew
Mildew is a form of fungus. It is distinguished from its closely related counterpart, mould, largely by its colour: moulds appear in shades of black, blue, red, and green, whereas mildew is white. It appears as a thin, superficial growth consisting of minute hyphae (fungal filaments) produced especially on living plants or organic matter such as wood, paper or leather. Both mould and mildew produce distinct offensive odours, and both have been identified as the cause of certain human ailments. In horticulture, mildew is either species of fungus in the order Erysiphales, or fungus-like organisms in the family ''Peronosporaceae''. It is also used more generally to mean mould growth. In Old English, mildew meant honeydew (a substance secreted by aphids on leaves, formerly thought to distill from the air like dew), and later came to mean mould or fungus. Mildew grows on damp cloth, leather, or on plants, and growing on leaves can damage the plant. Household varieties The term ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
