ash

ash,

in chemistry, solid residue of combustion. The chemical composition of an ash depends on that of the substance burned. Wood ash contains metal carbonates (e.g., potassium carbonate) and oxides formed from metals originally compounded in the wood. Coal ash usually has a high content of minerals and is sometimes contaminated with rock; during combustion the mineral matter may become partially fused, forming cinders or clinker. Bone ash is largely made up of calcium phosphate. Seaweed ash (called kelp or varec) contains sodium carbonate, potassium carbonate, and iodine that can be extracted. Fly ash is very fine ash produced during the combustion of many materials.

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ash,

in botany, any plant of the genus Fraxinus of the family Oleaceae (olive family), trees and shrubs mainly of north temperate regions. The ashes are characterized by small clusters of greenish flowers and by fruits with long "wings" to aid in wind dispersal. The most valuable of the North American species used for hardwood timber is the white ash (F. americana), ranging from Nova Scotia to Minnesota and Texas. Its strong, durable wood is used for sporting goods, furniture, tool handles, and oars. The bark of the blue ash (F. quadrangulata), which is found from the S Midwest to Oklahoma and Tennessee, yields a blue dye. Both the white ash, blue ash, and other North American species as well as the European ash (F. excelsior) are threatened by the emerald ash borer, a beetle native to Asia whose larvae kill ash trees by boring under the bark and into the wood, cutting off the flow of nutrients. Ash dieback, in which crown dieback and leaf loss results from infection with the fungus Hymenoscyphus fraxineus, also is a threat to the European ash. The Mediterranean flowering ash (F. ornus) is the source of commercial manna. The name flowering ash is also applied to a shrubby species (F. cuspidata) of the California canyon chaparral and to the fringe tree (genus Chionanthus of the same family) of North America and China. The mountain ash and prickly ash are not true ashes. Ashes are classified in the division Magnoliophyta, class Magnoliopsida, order Scrophulariales, family Oleaceae.

The Columbia Electronic Encyclopedia™ Copyright © 2013, Columbia University Press. Licensed from Columbia University Press. All rights reserved. www.cc.columbia.edu/cu/cup/

ash

ash

Tall tree, 100ft. Leaves green on top, lighter underneath, winged maple-like seeds. Antibacterial, anti-inflammatory used for cancer therapy. Bark tea used for liver, gallbladder, rheumatism, dysentery, kidney, lung, heart, nervous tension, cramps. Stimulates mucus surfaces, bile and pancreas. Chew bark for toothache. Can make tea from berries. Used for rheumatism because it stimulates circulation but blocks and calms nerve activity. Promotes sweating. Tea used externally for skin rash, itching etc.

Edible Plant Guide © 2012 Markus Rothkranz

The following article is from The Great Soviet Encyclopedia (1979). It might be outdated or ideologically biased.

Ash

 

an incombustible residue that is formed by the inorganic impurities in fuel after its complete combustion. The ash content of coal and lignite is 1–45 percent or more; that of combustible shales, 50–80 percent; that of fuel peat, 2–30 percent; that of firewood, usually less than 1 percent; that of other kinds of plant fuels, 3–5 percent; and that of mazut, usually up to 0.15 percent, but sometimes higher. The upper limit of the inorganic impurity content determines the technological possibility and economic feasibility of using a particular mineral as a fuel.

The presence of ash reduces the relative amount of combustibles in a fuel. Upon combustion of a fuel, part of the heat is lost with the ash. In boiler installations molten ash is deposited on the tubes of the furnace baffles, shields, and other parts as a sintered slag. The deposition of ash on heating surfaces inhibits the transfer of heat from furnace gases to the water or stem and increases the boiler’s aerodynamic resistance. Fly ash abrades boiler tubes and flue gas pumps, and ash pollutes the air when it is carried away with the flue gases.

In the building-materials industry ashes are used for making certain kinds of concrete. Rare and trace elements, such as germanium and gallium, are extracted from the ash of certain coals.

In agriculture, ash is widely used as a fertilizer containing potassium in the form of potash (K2CO3), which is readily soluble in water and available to plants. Other inorganic substances that are essential for plants (phosphorus, calcium, magnesium, sulfur, boron, and manganese); as well as other macroelements and trace elements, are present in ash. The high calcium carbonate content of shale and peat ash makes possible their use to reduce soil acidity. The average percentages in ash of compounds containing the main nutritive elements of plants are given in Table 1.

Table 1. Content of inorganic substances in ash used as fertilizer (percent)
	Potassium (K,0)	Phosphorus (P,0)	Calcium (CaO)
Sunflower-stem ash	30–35	2–4	18–20
Straw ash
buckwheat	25–35	2–4	16–19
rye	10–14	4–6	8–10
wheat	9–18	3–9	4–7
Firewood ash
birch	10–12	4–6	35–40
fir	3–4	2–3	23–26
pine	10–12	4–6	30–40
Manure ash	10–12	4–6	7–9
Peat ash	0.5–4.8	1.2–7.0	15–26
Shale ash	0.5–1.2	1.0–1.5	36–48

Ash is added to all soils and crops, but its use is most expedient with tobacco, potatoes, buckwheat, leguminous plants, flax, and fruit crops. It is introduced with the plowing, when turning over the soil under the crowns of trees (4–15 centners per hectare), and in planting potatoes, cabbage, and tomatoes (3–5 centners per hectare), as well as to fertilize meadows and cultivated and grain crops (3–5 centners per hectare). Ash must not be mixed with organic and ammonia fertilizers (to avoid loss of ammonia) or with superphosphate and other water-soluble phosphorus fertilizers (it causes retrogradation, reducing the ability of plants to assimilate phosphates).

REFERENCES

Agrokhimiia. Edited by V. M. Klechkovskii and A. V. Peterburgskii. Moscow, 1967.
Khimizatsiia sel’skogo khoziaistva: Nauchno-tekhnicheskii slovar’-spravochnik, 2nd ed. Edited by L. L. Balashev and S. I. VoPfkovich. Moscow, 1968.

A. V. PETERBURGSKII

The Great Soviet Encyclopedia, 3rd Edition (1970-1979). © 2010 The Gale Group, Inc. All rights reserved.

ash

[ash]

(botany)

A tree of the genus Fraxinus, deciduous trees of the olive family (Oleaceae) characterized by opposite, pinnate leaflets.

Any of various Australian trees having wood of great toughness and strength; used for tool handles and in work requiring flexibility.

(chemistry)

The incombustible matter remaining after a substance has been incinerated.

(engineering)

An undesirable constituent of diesel fuel whose quantitative measurement indicates degree of fuel cleanliness and freedom from abrasive material.

(geology)

Volcanic dust and particles less than 4 millimeters in diameter.

McGraw-Hill Dictionary of Scientific & Technical Terms, 6E, Copyright © 2003 by The McGraw-Hill Companies, Inc.

ash

A hard, strong, straight-grained hardwood of the eastern US having good shock resistance and bending qualities; used as flooring, trim, and decorative veneer.

McGraw-Hill Dictionary of Architecture and Construction. Copyright © 2003 by McGraw-Hill Companies, Inc.

ash

¹

1. the nonvolatile products and residue formed when matter is burnt

2. any of certain compounds formed by burning

3. fine particles of lava thrown out by an erupting volcano

4. a light silvery grey colour, often with a brownish tinge

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ash

²

1. any oleaceous tree of the genus Fraxinus, esp F. excelsior of Europe and Asia, having compound leaves, clusters of small greenish flowers, and winged seeds

2. the close-grained durable wood of any of these trees, used for tool handles, etc.

3. any of several trees resembling the ash, such as the mountain ash

4. Austral any of several Australian trees resembling the ash, esp of the eucalyptus genus

Collins Discovery Encyclopedia, 1st edition © HarperCollins Publishers 2005

ash

(tool)

A Bourne Shell clone by Kenneth Almquist. It works pretty well. For running scripts, it is sometimes better and sometimes worse than Bash.

Ash runs under 386BSD, NetBSD, FreeBSD, and Linux.

FTP Linux version.

This article is provided by FOLDOC - Free Online Dictionary of Computing (foldoc.org)