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Clothes Line
A clothes line or washing line is any type of rope, cord, or twine that has been stretched between two points (e.g. two sticks), outside or indoors, above the level of the ground. Clothing that has recently been washed is hung along the line to dry, using clothes pegs or clothespins. Washing lines are attached either from a post or a wall, and are frequently located in back gardens, or on balconies. Longer washing lines often have props holding up sections in the middle due to the weight of the usually wet clothing. More elaborate rotary washing lines save space and are typically retractable and square or triangular in shape, with multiple lines being used (such as the Hills Hoist from Australia). Some can be folded up when not in use (although there is a very minor hazard of getting fingers caught, so there is usually a safety button). In Scotland, many tenement buildings have a "drying green", which is a communal area predominantly used for clothes lines – it may also b ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hallig Hooge, Germany, View From The Backenswarft
The ''Halligen'' (German, singular ''Hallig'', ) or the ''halliger'' (Danish, singular ''hallig'') are small islands without protective dikes. They are variously pluralized in English as the Halligen, Halligs, Hallig islands, or Halligen islands. There are ten German ''halligen'' in the North Frisian Islands on Schleswig-Holstein's Wadden Sea-North Sea coast in the district of Nordfriesland and one hallig at the west coast of Denmark (Mandø). The name is cognate to Old-English ''halh'', meaning "slightly raised ground isolated by marsh". The very existence of the ''halligen'' is a result of frequent floods and poor coastal protection. The floods were much more common in the Middle Ages and coastal protection was much poorer. The ''halligen'' have areas ranging from 7 to 956 ha, and are often former parts of the mainland, separated therefrom by storm tide erosion. Some are also parts of once much bigger islands sundered by the same forces. Sometimes, owing to sediment deposition, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Static Cling
Static cling is the tendency for light objects to stick (cling) to other objects owing to static electricity. It is common in clothing, but occurs with other items, such as the tendency of dust to be attracted to, and stick to, plastic items. Cause and prevention In clothing, static cling occurs from static electricity. An electrostatic charge builds up on clothes due to the triboelectric effect when pieces of fabric rub against each other, as happens particularly in a clothes dryer. The separate positive and negatively charged surfaces attract each other. It is especially noticeable when humidity is low, allowing static electricity to build up. Certain substances can reduce static cling and are often included in fabric softener and dryer sheets. Antistatic agents, which make the surfaces slightly conductive, can be used on fabrics. Electronic devices Dust accumulation caused by static cling is a significant issue for computers and other electronic devices with heat gen ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Psychrometrics
Psychrometrics (or psychrometry, ; also called hygrometry) is the field of engineering concerned with the physical and thermodynamic properties of gas-vapor mixtures. Common applications Although the principles of psychrometry apply to any physical system consisting of gas-vapor mixtures, the most common system of interest is the mixture of water vapor and air, because of its application in heating, ventilation, and air-conditioning and meteorology. In human terms, our thermal comfort is in large part a consequence of not just the temperature of the surrounding air, but (because we cool ourselves via perspiration) the extent to which that air is saturated with water vapor. Many substances are hygroscopic, meaning they attract water, usually in proportion to the relative humidity or above a critical relative humidity. Such substances include cotton, paper, cellulose, other wood products, sugar, calcium oxide (burned lime) and many chemicals and fertilizers. Industries t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Condensation
Condensation is the change of the state of matter from the gas phase into the liquid phase, and is the reverse of vaporization. The word most often refers to the water cycle. It can also be defined as the change in the state of water vapor to liquid water when in contact with a liquid or solid surface or cloud condensation nuclei within the atmosphere. When the transition happens from the gaseous phase into the solid phase directly, the change is called deposition. Initiation Condensation is initiated by the formation of atomic/molecular clusters of that species within its gaseous volume—like rain drop or snow flake formation within clouds—or at the contact between such gaseous phase and a liquid or solid surface. In clouds, this can be catalyzed by water-nucleating proteins, produced by atmospheric microbes, which are capable of binding gaseous or liquid water molecules. Reversibility scenarios A few distinct reversibility scenarios emerge here with respect to t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Kilowatt-hours
A kilowatt-hour ( unit symbol: kW⋅h or kW h; commonly written as kWh) is a unit of energy: one kilowatt of power for one hour. In terms of SI derived units with special names, it equals 3.6 megajoules (MJ). Kilowatt-hours are a common billing unit for electrical energy delivered to consumers by electric utilities. Definition The kilowatt-hour is a composite unit of energy equal to one kilowatt (kW) sustained for (multiplied by) one hour. Expressed in the standard unit of energy in the International System of Units (SI), the joule (symbol J), it is equal to 3,600 kilojoules or 3.6 MJ."Half-high dots or spaces are used to express a derived unit formed from two or more other units by multiplication.", Barry N. Taylor. (2001 ed.''The International System of Units.'' (Special publication 330). Gaithersburg, MD: National Institute of Standards and Technology. 20. Unit representations A widely used representation of the kilowatt-hour is "kWh", derived from its comp ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Enthalpy Of Vaporization
The enthalpy of vaporization (symbol ), also known as the (latent) heat of vaporization or heat of evaporation, is the amount of energy (enthalpy) that must be added to a liquid substance to transform a quantity of that substance into a gas. The enthalpy of vaporization is a function of the pressure at which that transformation takes place. The enthalpy of vaporization is often quoted for the normal boiling temperature of the substance. Although tabulated values are usually corrected to 298 K, that correction is often smaller than the uncertainty in the measured value. The heat of vaporization is temperature-dependent, though a constant heat of vaporization can be assumed for small temperature ranges and for reduced temperature T_r \ll 1. The heat of vaporization diminishes with increasing temperature and it vanishes completely at a certain point called the critical temperature (T_r = 1). Above the critical temperature, the liquid and vapor phases are indistinguishable ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Kilogram
The kilogram (also kilogramme) is the unit of mass in the International System of Units (SI), having the unit symbol kg. It is a widely used measure in science, engineering and commerce worldwide, and is often simply called a kilo colloquially. It means 'one thousand grams'. The kilogram is defined in terms of the second and the metre, both of which are based on fundamental physical constants. This allows a properly equipped metrology laboratory to calibrate a mass measurement instrument such as a Kibble balance as the primary standard to determine an exact kilogram mass. The kilogram was originally defined in 1795 as the mass of one litre of water. The current definition of a kilogram agrees with this original definition to within 30 parts per million. In 1799, the platinum '' Kilogramme des Archives'' replaced it as the standard of mass. In 1889, a cylinder of platinum-iridium, the International Prototype of the Kilogram (IPK), became the standard of the unit of mass for ... [...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 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Convection
Convection is single or multiphase fluid flow that occurs spontaneously due to the combined effects of material property heterogeneity and body forces on a fluid, most commonly density and gravity (see buoyancy). When the cause of the convection is unspecified, convection due to the effects of thermal expansion and buoyancy can be assumed. Convection may also take place in soft solids or mixtures where particles can flow. Convective flow may be transient (such as when a multiphase mixture of oil and water separates) or steady state (see Convection cell). The convection may be due to gravitational, electromagnetic or fictitious body forces. Heat transfer by natural convection plays a role in the structure of Earth's atmosphere, its oceans, and its mantle. Discrete convective cells in the atmosphere can be identified by clouds, with stronger convection resulting in thunderstorms. Natural convection also plays a role in stellar physics. Convection is often categor ... [...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, t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Basement
A basement or cellar is one or more Storey, floors of a building that are completely or partly below the storey, ground floor. It generally is used as a utility space for a building, where such items as the Furnace (house heating), furnace, water heating, water heater, breaker panel or fuse box, Garage (residential), car park, and air-conditioning system are located; so also are amenities such as the electrical system and cable television distribution point. In cities with high property prices, such as London, basements are often fitted out to a high standard and used as living space. In British English, the word ''basement'' is usually used for underground floors of, for example, department stores. The word is usually used with houses when the space below the ground floor is habitable, with windows and (usually) its own access. The word ''cellar'' applies to the whole underground level or to any large underground room. A ''subcellar'' is a cellar that lies further underneath ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Apartment
An apartment (American English), or flat (British English, Indian English, South African English), is a self-contained housing unit (a type of residential real estate) that occupies part of a building, generally on a single story. There are many names for these overall buildings, see below. The housing tenure of apartments also varies considerably, from large-scale public housing, to owner occupancy within what is legally a condominium ( strata title or commonhold), to tenants renting from a private landlord (see leasehold estate). Terminology The term ''apartment'' is favored in North America (although in some cities ''flat'' is used for a unit which is part of a house containing two or three units, typically one to a floor). In the UK, the term ''apartment'' is more usual in professional real estate and architectural circles where otherwise the term ''flat'' is used commonly, but not exclusively, for an apartment on a single level (hence a 'flat' apartment). In some coun ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
