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Whitewash , calcimine , kalsomine , calsomine , asbestis or lime paint is a type of paint made from slaked lime ( calcium hydroxide , Ca(OH) 2 ) or chalk ( calcium carbonate , CaCO 3 ), sometimes known as "whiting". Various other additives are sometimes used.

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66-439: Whitewash cures through a reaction with carbon dioxide in the atmosphere to form calcium carbonate in the form of calcite , a type of reaction generally known as carbonation or by the more specific term, carbonatation . It is usually applied to exteriors, or interiors of rural dairies because of its mildly antibacterial properties. Whitewash can be tinted for decorative use and is sometimes painted inside structures such as

132-406: A bright sunny day following a period of warm cloudy humidity. The damage to the leaves will start as bronzing of the epidermis between the veins of the leaf, and if the sunny conditions persist the tissue of the leaf will die. Sun scald on fruit appears when a fruit is exposed to direct sunlight after cold storage for an extended period of time, typically after harvest. The damage can often lead to

198-516: A decline in basic activity level and information usage at 1000 ppm, when compared to 500 ppm. However a review of the literature found that a reliable subset of studies on the phenomenon of carbon dioxide induced cognitive impairment to only show a small effect on high-level decision making (for concentrations below 5000 ppm). Most of the studies were confounded by inadequate study designs, environmental comfort, uncertainties in exposure doses and differing cognitive assessments used. Similarly

264-446: A fixed structure. However, in a Coulomb explosion imaging experiment, an instantaneous image of the molecular structure can be deduced. Such an experiment has been performed for carbon dioxide. The result of this experiment, and the conclusion of theoretical calculations based on an ab initio potential energy surface of the molecule, is that none of the molecules in the gas phase are ever exactly linear. This counter-intuitive result

330-611: A glass state similar to other members of its elemental family, like silicon dioxide (silica glass) and germanium dioxide . Unlike silica and germania glasses, however, carbonia glass is not stable at normal pressures and reverts to gas when pressure is released. At temperatures and pressures above the critical point, carbon dioxide behaves as a supercritical fluid known as supercritical carbon dioxide . Table of thermal and physical properties of saturated liquid carbon dioxide: Table of thermal and physical properties of carbon dioxide (CO 2 ) at atmospheric pressure: Carbon dioxide

396-408: A leathery or wrinkled appearance and a pale discoloration. The terms "sun scald" and "sunburn" are frequently used interchangeably, however fruit sunburn is generally distinguished by only occurring pre-harvest and leaving yellow, bronze, or brown discoloration of the skin. Fruits damaged to either extent are usually considered unmarketable due to diminished appearance, taste, and texture, but those of

462-491: A mature forest will produce as much CO 2 from respiration and decomposition of dead specimens (e.g., fallen branches) as is used in photosynthesis in growing plants. Contrary to the long-standing view that they are carbon neutral, mature forests can continue to accumulate carbon and remain valuable carbon sinks , helping to maintain the carbon balance of Earth's atmosphere. Additionally, and crucially to life on earth, photosynthesis by phytoplankton consumes dissolved CO 2 in

528-428: A much larger denominator and a much smaller value than the true K a1 . The bicarbonate ion is an amphoteric species that can act as an acid or as a base, depending on pH of the solution. At high pH, it dissociates significantly into the carbonate ion ( CO 2− 3 ): In organisms, carbonic acid production is catalysed by the enzyme known as carbonic anhydrase . In addition to altering its acidity,

594-529: A peeling wall. The only approach is to scrape it off. The chalk releases the paint in large flakes or small chips. While working, the wall sections of paint will appear to be solid and later come off easily. It is a long process. The incident of Tom Sawyer whitewashing a fence as punishment is a famous image in American literature. It appears in The Adventures of Tom Sawyer written in 1876 by Mark Twain . In

660-416: A study on the effects of the concentration of CO 2 in motorcycle helmets has been criticized for having dubious methodology in not noting the self-reports of motorcycle riders and taking measurements using mannequins. Further when normal motorcycle conditions were achieved (such as highway or city speeds) or the visor was raised the concentration of CO 2 declined to safe levels (0.2%). Poor ventilation

726-467: A typical single C–O bond, and shorter than most other C–O multiply bonded functional groups such as carbonyls . Since it is centrosymmetric, the molecule has no electric dipole moment . As a linear triatomic molecule, CO 2 has four vibrational modes as shown in the diagram. In the symmetric and the antisymmetric stretching modes, the atoms move along the axis of the molecule. There are two bending modes, which are degenerate , meaning that they have

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792-485: A waste product. In turn, oxygen is consumed and CO 2 is released as waste by all aerobic organisms when they metabolize organic compounds to produce energy by respiration . CO 2 is released from organic materials when they decay or combust, such as in forest fires. When carbon dioxide dissolves in water, it forms carbonate and mainly bicarbonate ( HCO − 3 ), which causes ocean acidification as atmospheric CO 2 levels increase. Carbon dioxide

858-469: Is Emiliania huxleyi whose calcite scales have formed the basis of many sedimentary rocks such as limestone , where what was previously atmospheric carbon can remain fixed for geological timescales. Plants can grow as much as 50% faster in concentrations of 1,000 ppm CO 2 when compared with ambient conditions, though this assumes no change in climate and no limitation on other nutrients. Elevated CO 2 levels cause increased growth reflected in

924-419: Is 304.128(15) K (30.978(15) °C) at 7.3773(30) MPa (72.808(30) atm). Another form of solid carbon dioxide observed at high pressure is an amorphous glass-like solid. This form of glass, called carbonia , is produced by supercooling heated CO 2 at extreme pressures (40–48  GPa , or about 400,000 atmospheres) in a diamond anvil . This discovery confirmed the theory that carbon dioxide could exist in

990-566: Is 53% more dense than dry air, but is long lived and thoroughly mixes in the atmosphere. About half of excess CO 2 emissions to the atmosphere are absorbed by land and ocean carbon sinks . These sinks can become saturated and are volatile, as decay and wildfires result in the CO 2 being released back into the atmosphere. CO 2 is eventually sequestered (stored for the long term) in rocks and organic deposits like coal , petroleum and natural gas . Nearly all CO2 produced by humans goes into

1056-406: Is a chemical compound with the chemical formula CO 2 . It is made up of molecules that each have one carbon atom covalently double bonded to two oxygen atoms. It is found in the gas state at room temperature and at normally-encountered concentrations it is odorless. As the source of carbon in the carbon cycle , atmospheric CO 2 is the primary carbon source for life on Earth. In

1122-415: Is an end product of cellular respiration in organisms that obtain energy by breaking down sugars, fats and amino acids with oxygen as part of their metabolism . This includes all plants, algae and animals and aerobic fungi and bacteria. In vertebrates , the carbon dioxide travels in the blood from the body's tissues to the skin (e.g., amphibians ) or the gills (e.g., fish ), from where it dissolves in

1188-402: Is commercially used in its solid form, commonly known as " dry ice ". The solid-to-gas phase transition occurs at 194.7 Kelvin and is called sublimation . The symmetry of a carbon dioxide molecule is linear and centrosymmetric at its equilibrium geometry. The length of the carbon–oxygen bond in carbon dioxide is 116.3  pm , noticeably shorter than the roughly 140 pm length of

1254-436: Is especially compatible with masonry because it is absorbed easily and the resultant chemical reaction hardens the medium. Lime wash is pure slaked lime in water. It produces a unique surface glow due to the double refraction of calcite crystals. Limewash and whitewash both cure to become the same material. When whitewash or limewash is initially applied, it has very low opacity , which can lead novices to overthicken

1320-632: Is one of the main causes of excessive CO 2 concentrations in closed spaces, leading to poor indoor air quality . Carbon dioxide differential above outdoor concentrations at steady state conditions (when the occupancy and ventilation system operation are sufficiently long that CO 2 concentration has stabilized) are sometimes used to estimate ventilation rates per person. Higher CO 2 concentrations are associated with occupant health, comfort and performance degradation. ASHRAE Standard 62.1–2007 ventilation rates may result in indoor concentrations up to 2,100 ppm above ambient outdoor conditions. Thus if

1386-410: Is ordinarily a difficult and slow reaction: The redox potential for this reaction near pH 7 is about −0.53 V versus the standard hydrogen electrode . The nickel-containing enzyme carbon monoxide dehydrogenase catalyses this process. Photoautotrophs (i.e. plants and cyanobacteria ) use the energy contained in sunlight to photosynthesize simple sugars from CO 2 absorbed from

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1452-405: Is produced as a by-product. Ribulose-1,5-bisphosphate carboxylase oxygenase , commonly abbreviated to RuBisCO, is the enzyme involved in the first major step of carbon fixation, the production of two molecules of 3-phosphoglycerate from CO 2 and ribulose bisphosphate , as shown in the diagram at left. RuBisCO is thought to be the single most abundant protein on Earth. Phototrophs use

1518-430: Is short, so this is added at point of use. Cement restricts the breathable aspects of the limewash and is inadvisable for preserved historic buildings. Dilute glues improve paint toughness. Wheat flour has been used as a strength enhancing binder. Salt is often added to prevent mold . Basic limewash can be inadequate in its ability to prevent rain-driven water ingress. Additives are being developed but these have

1584-472: Is the true first acid dissociation constant, defined as where the denominator includes only covalently bound H 2 CO 3 and does not include hydrated CO 2 (aq). The much smaller and often-quoted value near 4.16 × 10 (or pK a1 = 6.38) is an apparent value calculated on the (incorrect) assumption that all dissolved CO 2 is present as carbonic acid, so that Since most of the dissolved CO 2 remains as CO 2 molecules, K a1 (apparent) has

1650-545: Is the main cause of these increased CO 2 concentrations, which are the primary cause of climate change . Its concentration in Earth's pre-industrial atmosphere since late in the Precambrian was regulated by organisms and geological features. Plants , algae and cyanobacteria use energy from sunlight to synthesize carbohydrates from carbon dioxide and water in a process called photosynthesis , which produces oxygen as

1716-419: Is trivially due to the fact that the nuclear motion volume element vanishes for linear geometries. This is so for all molecules except diatomic molecules . Carbon dioxide is soluble in water, in which it reversibly forms H 2 CO 3 (carbonic acid), which is a weak acid , because its ionization in water is incomplete. The hydration equilibrium constant of carbonic acid is, at 25 °C: Hence,

1782-465: Is used in CO 2 scrubbers and has been suggested as a possible starting point for carbon capture and storage by amine gas treating . Only very strong nucleophiles, like the carbanions provided by Grignard reagents and organolithium compounds react with CO 2 to give carboxylates : In metal carbon dioxide complexes , CO 2 serves as a ligand , which can facilitate the conversion of CO 2 to other chemicals. The reduction of CO 2 to CO

1848-464: The 1934 film, Fugitive Lovers , Madge Evans drops a bottle of cosmetics that she calls her "Calcimine". Metaphorically, whitewashing refers to suppression or "glossing over" (possibly a close parallel construction) of potentially damaging or unwelcome information. In many Commonwealth areas, a whitewash refers to a game in which one side fails to score at all; the usage is especially found in cricket . Carbon dioxide Carbon dioxide

1914-567: The UK, Ireland and Australia, Loulaki in Greece, or Mrs. Stewart's Bluing in North America), formerly widely used to give a bright tinge to boiled white textiles, was a common 19th century addition. Historically, pig's blood was added to give the colour Suffolk pink , a colour still widely used on house exteriors in some areas of the UK. If animal blood is applied excessively, its iron oxide can compromise

1980-439: The air and water: Carbon dioxide is colorless. At low concentrations, the gas is odorless; however, at sufficiently high concentrations, it has a sharp, acidic odor. At standard temperature and pressure , the density of carbon dioxide is around 1.98 kg/m , about 1.53 times that of air . Carbon dioxide has no liquid state at pressures below 0.51795(10) MPa (5.11177(99) atm ). At a pressure of 1 atm (0.101325 MPa),

2046-444: The air, carbon dioxide is transparent to visible light but absorbs infrared radiation , acting as a greenhouse gas . Carbon dioxide is soluble in water and is found in groundwater , lakes , ice caps , and seawater . It is a trace gas in Earth's atmosphere at 421  parts per million (ppm) , or about 0.042% (as of May 2022) having risen from pre-industrial levels of 280 ppm or about 0.028%. Burning fossil fuels

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2112-430: The atmosphere. Less than 1% of CO2 produced annually is put to commercial use, mostly in the fertilizer industry and in the oil and gas industry for enhanced oil recovery . Other commercial applications include food and beverage production, metal fabrication, cooling, fire suppression and stimulating plant growth in greenhouses. Carbon dioxide cannot be liquefied at atmospheric pressure. Low-temperature carbon dioxide

2178-439: The ceiling. If left alone, these surfaces collect dust, dirt, insect debris and wastes, and can become very dirty. Whitewash aids in sanitation by coating and smoothing over the rough surfaces. Successive applications of whitewash build up layers of scale that flake off and, in the process, remove surface debris. The coating also has antimicrobial properties that provide hygienic and sanitary benefits for animal barns . Whitewash

2244-862: The condition. There are few studies of the health effects of long-term continuous CO 2 exposure on humans and animals at levels below 1%. Occupational CO 2 exposure limits have been set in the United States at 0.5% (5000 ppm) for an eight-hour period. At this CO 2 concentration, International Space Station crew experienced headaches, lethargy, mental slowness, emotional irritation, and sleep disruption. Studies in animals at 0.5% CO 2 have demonstrated kidney calcification and bone loss after eight weeks of exposure. A study of humans exposed in 2.5 hour sessions demonstrated significant negative effects on cognitive abilities at concentrations as low as 0.1% (1000   ppm) CO 2 likely due to CO 2 induced increases in cerebral blood flow. Another study observed

2310-400: The death of the fruit via consumption by insects, animals, bacteria, or fungi. This is the case if the defenses of the fruit are too heavily inflicted, which may occur when the outer skin is damaged to the point that the cell walls/membranes are either gone or weak enough for the plant's enemies to penetrate. Sun scald often presents as more of an internal damage, with the affected tissue gaining

2376-510: The degenerate pair of bending modes at 667 cm (wavelength 15.0 μm). The symmetric stretching mode does not create an electric dipole so is not observed in IR spectroscopy, but it is detected in Raman spectroscopy at 1388 cm (wavelength 7.20 μm), with a Fermi resonance doublet at 1285 cm . In the gas phase, carbon dioxide molecules undergo significant vibrational motions and do not keep

2442-566: The dispersing effects of wind, it can collect in sheltered/pocketed locations below average ground level, causing animals located therein to be suffocated. Carrion feeders attracted to the carcasses are then also killed. Children have been killed in the same way near the city of Goma by CO 2 emissions from the nearby volcano Mount Nyiragongo . The Swahili term for this phenomenon is mazuku . Adaptation to increased concentrations of CO 2 occurs in humans, including modified breathing and kidney bicarbonate production, in order to balance

2508-541: The effects of blood acidification ( acidosis ). Several studies suggested that 2.0 percent inspired concentrations could be used for closed air spaces (e.g. a submarine ) since the adaptation is physiological and reversible, as deterioration in performance or in normal physical activity does not happen at this level of exposure for five days. Yet, other studies show a decrease in cognitive function even at much lower levels. Also, with ongoing respiratory acidosis , adaptation or compensatory mechanisms will be unable to reverse

2574-551: The electrical conductivity of fully deionized water without CO 2 saturation is comparably low in relation to these data. CO 2 is a potent electrophile having an electrophilic reactivity that is comparable to benzaldehyde or strongly electrophilic α,β-unsaturated carbonyl compounds . However, unlike electrophiles of similar reactivity, the reactions of nucleophiles with CO 2 are thermodynamically less favored and are often found to be highly reversible. The reversible reaction of carbon dioxide with amines to make carbamates

2640-427: The expanding and contracting of the tree trunk. When sun scald appears on trees it is most frequently a result of reflected light off the snow during winter months. The damage in this case will appear as sunken or dead bark on the trunk of the tree, then later in the tree's life the bark might fall away revealing dead tissue in the tree's cambium layer. This damage will typically be found on the south west facing side of

2706-469: The gas deposits directly to a solid at temperatures below 194.6855(30) K (−78.4645(30) °C) and the solid sublimes directly to a gas above this temperature. In its solid state, carbon dioxide is commonly called dry ice . Liquid carbon dioxide forms only at pressures above 0.51795(10) MPa (5.11177(99) atm); the triple point of carbon dioxide is 216.592(3) K (−56.558(3) °C) at 0.51795(10) MPa (5.11177(99) atm) (see phase diagram). The critical point

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2772-413: The growth of the tree and harbor insects that may damage the tree. Painting the tree white has the same effect as wrapping, although it is a permanent change to the color of the tree. This discoloration can be aesthetically displeasing, so this method is mostly used in orchards and rarely in landscaping. The amount of light a tree receives on its southwest side is correlated with the amount of sun scald

2838-505: The hallways of apartment buildings. A small amount can rub off onto clothing . In Britain and Ireland, whitewash was used historically in interiors and exteriors of workers' cottages and still retains something of this association with rural poverty . In the United States, a similar attitude is expressed in the old saying "Too proud to whitewash and too poor to paint." The historic California Missions were commonly whitewashed, giving them their distinctive bright white appearance. Whitewash

2904-597: The harvestable yield of crops, with wheat, rice and soybean all showing increases in yield of 12–14% under elevated CO 2 in FACE experiments. Increased atmospheric CO 2 concentrations result in fewer stomata developing on plants which leads to reduced water usage and increased water-use efficiency . Studies using FACE have shown that CO 2 enrichment leads to decreased concentrations of micronutrients in crop plants. This may have knock-on effects on other parts of ecosystems as herbivores will need to eat more food to gain

2970-427: The latter are sometimes sold at a lower grade or utilized as an (often puréed) ingredient. Sun damage cannot be reversed, but the fruit may still be able to fend off attacks and partially recover if properly treated and protected from further damage. The treatment of sun scalding is fundamentally simple: reduce the intensity of the sun, or block the sun completely. The most common method used to prevent sun scalding on

3036-401: The lime binder's strength. Pozzolanic materials are occasionally added to give a much harder wearing paint finish. This addition creates a short open time and therefore requires timely application of the altered paint. Linseed oil is sometimes added (typically 0.5-2%) to improve adhesion on difficult surfaces. Cement addition makes a harder wearing paint in white or grey . Open time

3102-476: The limewash. Damping down is not difficult but it does need to be considered before application of the limewash. Additives traditionally used include water glass , glue , egg white , Portland cement , salt , soap , milk , flour , molasses, alum, and soil . Whitewash is sometimes coloured with earths to achieve colours spanning the range of broken white , cream , yellow and a range of browns . The blue laundry dye (such as Reckitt's "Dolly Blue" in

3168-444: The majority of the carbon dioxide is not converted into carbonic acid, but remains as CO 2 molecules, not affecting the pH. The relative concentrations of CO 2 , H 2 CO 3 , and the deprotonated forms HCO − 3 ( bicarbonate ) and CO 2− 3 ( carbonate ) depend on the pH . As shown in a Bjerrum plot , in neutral or slightly alkaline water (pH > 6.5), the bicarbonate form predominates (>50%) becoming

3234-443: The most prevalent (>95%) at the pH of seawater. In very alkaline water (pH > 10.4), the predominant (>50%) form is carbonate. The oceans, being mildly alkaline with typical pH = 8.2–8.5, contain about 120 mg of bicarbonate per liter. Being diprotic , carbonic acid has two acid dissociation constants , the first one for the dissociation into the bicarbonate (also called hydrogen carbonate) ion ( HCO − 3 ): This

3300-417: The northern hemisphere, it is also called southwest injury . The reason the sun can cause so much damage to trees is because of dormancy . When a tree is dormant in the winter it can be reactivated by warm weather. In the northern woods trees are exposed to the most sunlight and heat on the southwest facing side, so this side is heated during warm sunny winter days (in the afternoon, that's why westwards) to

3366-465: The outdoor concentration is 400 ppm, indoor concentrations may reach 2,500 ppm with ventilation rates that meet this industry consensus standard. Concentrations in poorly ventilated spaces can be found even higher than this (range of 3,000 or 4,000 ppm). Sun scald (flora) Sun scald is the freezing of bark following high temperatures in the winter season, resulting in permanent visible damage to bark. Fruits may also be damaged. In

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3432-437: The paint. Drying increases opacity and subsequent curing increases opacity even further. Limewash relies on being drawn into a substrate unlike a modern paint that adheres to the surface. The process of being drawn in needs to be controlled by damping down. If a wall is not damped, it can leave the lime and pigments on the surface powdery; if the wall is saturated, then there is no surface tension and this can result in failure of

3498-442: The point that it can be awoken from dormancy. The temperature required to wake up a tree depends on plant species and length of day, but it is typically just above freezing. Once active, the cells on the southwest side of the plant are unable to return to dormancy by nightfall, at which time the temperature returns to levels capable of killing active cells. Fluctuating winter temperatures can also cause frost cracks , which result from

3564-674: The potential for affecting free vapor permeability. For this reason silicate paints , more common in Germany, are gaining popularity in the UK over limewash. Whitewash is applied to trees, especially fruit trees, to prevent sun scald . Most often only the lower trunk is painted. In Poland painting the whole trunk is also said to help keep the body of the tree cool in late winter and early spring months and hence help prevent fruit trees from blooming too soon, i.e. when warm sunny days could promote rapid tree warming, rising sap and bloom and intermittent frosty nights could damage outer tree rings and destroy

3630-495: The presence of carbon dioxide in water also affects its electrical properties. When carbon dioxide dissolves in desalinated water, the electrical conductivity increases significantly from below 1 μS/cm to nearly 30 μS/cm. When heated, the water begins to gradually lose the conductivity induced by the presence of C O 2 {\displaystyle \mathrm {CO_{2}} } , especially noticeable as temperatures exceed 30 °C. The temperature dependence of

3696-499: The presence of sufficient oxygen, manifesting as dizziness, headache, visual and hearing dysfunction, and unconsciousness within a few minutes to an hour. Concentrations of more than 10% may cause convulsions, coma, and death. CO 2 levels of more than 30% act rapidly leading to loss of consciousness in seconds. Because it is heavier than air, in locations where the gas seeps from the ground (due to sub-surface volcanic or geothermal activity) in relatively high concentrations, without

3762-496: The products of their photosynthesis as internal food sources and as raw material for the biosynthesis of more complex organic molecules, such as polysaccharides , nucleic acids , and proteins. These are used for their own growth, and also as the basis of the food chains and webs that feed other organisms, including animals such as ourselves. Some important phototrophs, the coccolithophores synthesise hard calcium carbonate scales. A globally significant species of coccolithophore

3828-420: The same amount of protein. The concentration of secondary metabolites such as phenylpropanoids and flavonoids can also be altered in plants exposed to high concentrations of CO 2 . Plants also emit CO 2 during respiration, and so the majority of plants and algae, which use C3 photosynthesis , are only net absorbers during the day. Though a growing forest will absorb many tons of CO 2 each year,

3894-411: The same frequency and same energy, because of the symmetry of the molecule. When a molecule touches a surface or touches another molecule, the two bending modes can differ in frequency because the interaction is different for the two modes. Some of the vibrational modes are observed in the infrared (IR) spectrum : the antisymmetric stretching mode at wavenumber 2349 cm (wavelength 4.25 μm) and

3960-416: The tree endures. Reducing the amount of light the tree is exposed to by planting a shrub or bush strategically to shade the southwest side can be less effective than wrapping or painting, but can have better aesthetic qualities for landscaping. For fruit the most important part of avoiding sun scald is to be aware of where the fruit has been during its growth. If the fruit grew in the shade then exposing it to

4026-432: The tree's trunk. It can be found on other sides of the tree if there is light reflection from other sources, like man made structures or reflective rock faces. After a tree is afflicted by sun scald it becomes much more vulnerable to decay organisms. The plant will create walls around the affected area, but sometimes it is not enough to block the infections. The leaves of the tree are also affected by sun scald, particularly on

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4092-408: The trunks of trees is to wrap the tree up to the first branch with white paper overlapping approximately thirty three percent each time around the tree. The white paper is effective in reflecting the heat of the sun off the tree. The paper should be applied after the tree has gone dormant for the winter and taken off before it becomes active again. If the paper is left on too long it can interfere with

4158-535: The upper ocean and thereby promotes the absorption of CO 2 from the atmosphere. Carbon dioxide content in fresh air (averaged between sea-level and 10 kPa level, i.e., about 30 km (19 mi) altitude) varies between 0.036% (360 ppm) and 0.041% (412 ppm), depending on the location. In humans, exposure to CO 2 at concentrations greater than 5% causes the development of hypercapnia and respiratory acidosis . Concentrations of 7% to 10% (70,000 to 100,000 ppm) may cause suffocation, even in

4224-546: The water, or to the lungs from where it is exhaled. During active photosynthesis, plants can absorb more carbon dioxide from the atmosphere than they release in respiration. Carbon fixation is a biochemical process by which atmospheric carbon dioxide is incorporated by plants, algae and cyanobacteria into energy-rich organic molecules such as glucose , thus creating their own food by photosynthesis. Photosynthesis uses carbon dioxide and water to produce sugars from which other organic compounds can be constructed, and oxygen

4290-516: The young buds and blossoms. In the middle of the 20th century, when family farms with dairy barns were common in the Upper Midwest of the United States , whitewash was a necessary part of routine barn maintenance . A traditional animal barn contains a variety of extremely rough surfaces that are difficult to wash and keep clean, such as stone and brick masonry, and also rough-cut lumber for

4356-683: Was painted on the internal walls of Royal Navy vessels during the Age of Sail to improve light levels inside a vessel's gundeck , reduce bacteria and prevent wear and tear on hull timbers. It was also used during the Second World War by the German armed forces as an easy-to-apply winter camouflage for soft- and hard-skinned vehicles, aircraft and helmets. While calcimine was generally stable with oil paint, current latex paints blister and peel. No success has been reported with primers and other glues over top of

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