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Creosote Bush Flower Stages
Creosote is a category of carbonaceous chemicals formed by the distillation of various tars and pyrolysis of plant-derived material, such as wood, or fossil fuel. They are typically used as preservatives or antiseptics. Some creosote types were used historically as a treatment for components of seagoing and outdoor wood structures to prevent rot (e.g., bridgework and railroad ties, see image). Samples may be found commonly inside chimney flues, where the coal or wood burns under variable conditions, producing soot and tarry smoke. Creosotes are the principal chemicals responsible for the stability, scent, and flavor characteristic of smoked meat; the name is derived . The two main kinds recognized in industry are coal tar, coal-tar creosote and tar, wood-tar creosote. The coal-tar variety, having stronger and more toxic properties, has chiefly been used as a preservative for wood; coal-tar creosote was also formerly used as an escharotic, to burn malignant skin tissue, and in d ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Water Gas
Water gas is a kind of fuel gas, a mixture of carbon monoxide and hydrogen. It is produced by "alternately hot blowing a fuel layer okewith air and gasifying it with steam". The caloric yield of the fuel produced by this method is about 10% of the yield from a modern syngas plant. The coke needed to produce water gas also costs significantly more than the precursors for syngas (mainly methane from natural gas), making water gas technology an even less attractive business proposition. Production Synthesis gas is made by passing steam over a red-hot carbon fuel such as coke: : (Δ''H'' = +131 kJ/mol) The reaction is endothermic, so the fuel must be continually re-heated to maintain the reaction. To do this, an air stream, which alternates with the vapor stream, is introduced to combust some of the carbon: : (Δ''H'' = −393 kJ/mol) Theoretically, to make 6 L of water gas, 5 L of air is required. Alternatively, to prevent contamination with nitrogen, energy can be p ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Putrefaction
Putrefaction is the fifth stage of death, following pallor mortis, livor mortis, algor mortis, and rigor mortis. This process references the breaking down of a body of an animal Post-mortem interval, post-mortem. In broad terms, it can be viewed as the decomposition of proteins, and the eventual breakdown of the cohesiveness between tissues, and the liquefaction of most organs. This is caused by the decomposition of organic matter by bacterial or fungal digestion, which causes the release of gases that infiltrate the body's tissues, and leads to the deterioration of the tissues and organs. The approximate time it takes putrefaction to occur is dependent on various factors. Internal factors that affect the rate of putrefaction include the age at which death has occurred, the overall structure and condition of the body, the cause of death, and external injuries arising before or after death. External factors include environmental temperature, moisture and air exposure, clothing, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Dry Distillation
Dry distillation is the heating of solid materials to produce gaseous products (which may condense into liquids or solids). The method may involve pyrolysis or thermolysis, or it may not (for instance, a simple mixture of ice and glass could be separated without breaking any chemical bonds, but organic matter contains a greater diversity of molecules, some of which are likely to break). If there are no chemical changes, just phase changes, it resembles classical distillation, although it will generally need higher temperatures. Dry distillation in which chemical changes occur is a type of destructive distillation or cracking. Uses The method has been used to obtain liquid fuels from coal and wood. It can also be used to break down mineral salts such as sulfates () through thermolysis, in this case producing sulfur dioxide (SO2) or sulfur trioxide (SO3) gas which can be dissolved in water to obtain sulfuric acid. By this method sulfuric acid was first identified and artific ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pyroligneous Acid
Pyroligneous acid, also called wood vinegar or wood acid, is a dark liquid produced by the destructive distillation of wood and other plant materials. Composition The principal components of pyroligneous acid are 10% acetic acid, acetone and methanol. It was once used as a commercial source for acetic acid. History Pyroligneous acid (acetum lignorum) was investigated by German chemist Johann Rudolph Glauber. The acid was used as a substitute for vinegar. It was also used topically for treating wounds, ulcers and other ailments. A salt can be made by neutralizing the acid with a lye made from the ashes of the burnt wood. During the United States Civil War it became increasingly difficult for the Confederate States of America to obtain much needed salt. Curing meat and fish with pyroligneous acid was attempted by cooks to compensate for this deficiency, but it was insufficient. In the nineteenth century, pyroligneous acid was used to prepare an impure aluminium sulfacetate ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Carl Reichenbach
Karl Ludwig Freiherr von Reichenbach (; February 12, 1788January 19, 1869), known as Carl Reichenbach, was a German chemist, geologist, metallurgist, naturalist, industrialist and philosopher, and a member of the Prussian Academy of Sciences. He is best known for his discoveries of several chemical products of economic importance, extracted from tar, such as eupione, waxy paraffin, pittacal (the first synthetic dye) and phenol (an antiseptic). He also dedicated his last years to researching an unproved field of energy combining electricity, magnetism and heat, emanating from all living things, which he called the Odic force. Life Reichenbach was educated at the University of Tübingen, where he obtained the degree of doctor of philosophy. At the age of 16 he conceived the idea of establishing a new German state in one of the South Sea Islands, and for five years he devoted himself to this project. Afterwards, directing his attention to the application of science to the industr ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Anthracene
Anthracene is a solid polycyclic aromatic hydrocarbon (PAH) of formula C14H10, consisting of three fused benzene rings. It is a component of coal tar. Anthracene is used in the production of the red dye alizarin and other dyes, as a scintillator to detect high energy particles, as production of pharmaceutical drugs. Anthracene is colorless but exhibits a blue (400–500 nm peak) fluorescence under ultraviolet radiation. History and etymology Crude anthracene (with a melting point of only 180°) was discovered in 1832 by Jean-Baptiste Dumas and Auguste Laurent who crystalized it from a fraction of coal tar later known as "anthracene oil". Since their (inaccurate) measurements showed the proportions of carbon and hydrogen of it to be the same as in naphthalene, Laurent called it ''paranaphtaline'' in his 1835 publication of the discovery, which is translated to English as paranaphthalene. Two years later, however, he decided to rename the compound to its modern name d ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Naphthalene
Naphthalene is an organic compound with formula . It is the simplest polycyclic aromatic hydrocarbon, and is a white Crystal, crystalline solid with a characteristic odor that is detectable at concentrations as low as 0.08 Parts-per notation, ppm by mass. As an Aromaticity, aromatic hydrocarbon, naphthalene's structure consists of a fused pair of benzene rings. It is the main ingredient of traditional mothballs. History In the early 1820s, two separate reports described a white solid with a pungent odor derived from the distillation of coal tar. In 1821, John Kidd (chemist), John Kidd cited these two disclosures and then described many of this substance's properties and the means of its production. He proposed the name ''naphthaline'', as it had been derived from a kind of naphtha (a broad term encompassing any volatile, flammable liquid hydrocarbon mixture, including coal tar). Naphthalene's chemical formula was determined by Michael Faraday in 1826. The structure of two f ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Phenol
Phenol (also known as carbolic acid, phenolic acid, or benzenol) is an aromatic organic compound with the molecular formula . It is a white crystalline solid that is volatile and can catch fire. The molecule consists of a phenyl group () bonded to a hydroxy group (). Mildly acidic, it requires careful handling because it can cause chemical burns. It is acutely toxic and is considered a health hazard. Phenol was first extracted from coal tar, but today is produced on a large scale (about 7 million tonnes a year) from petroleum-derived feedstocks. It is an important industrial commodity as a precursor to many materials and useful compounds, and is a liquid when manufactured. It is primarily used to synthesize plastics and related materials. Phenol and its chemical derivatives are essential for production of polycarbonates, epoxies, explosives such as picric acid, Bakelite, nylon, detergents, herbicides such as phenoxy herbicides, and numerous pharmaceuti ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Deep Foundation
A pile or piling is a vertical structural element of a deep foundation, driven or drilled deep into the ground at the building site. A deep foundation is a type of foundation (architecture), foundation that transfers building loads to the earth farther down from the surface than a shallow foundation does to a subsurface layer or a range of depths. There are many reasons that a geotechnical engineer would recommend a deep foundation over a shallow foundation, such as for a skyscraper. Some of the common reasons are very large design loads, a poor soil at shallow depth, or site constraints like property lines. There are different terms used to describe different types of deep foundations including the pile (which is analogous to a pole), the pier (which is analogous to a column), drilled shafts, and Caisson (engineering), caissons. Piles are generally driven into the ground ''in situ''; other deep foundations are typically put in place using excavation and drilling. The namin ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Carbonization
Carbonization or carbonisation is the conversion of organic matters like plants and dead animal remains into carbon through destructive distillation. Complexity in carbonization Carbonization is a pyrolytic reaction, therefore, is considered a complex process in which many reactions take place concurrently such as dehydrogenation, Condensation reaction, condensation, Transfer hydrogenation, hydrogen transfer and isomerization. Carbonization differs from Coal#Geology, coalification in that it occurs much faster, due to its reaction rate being faster by many orders of magnitude. For the final pyrolysis temperature, the amount of heat applied controls the degree of carbonization and the residual content of foreign elements. For example, at T ~ the carbon content of the residue exceeds a mass fraction of 90 wt.%, whereas at T ~ more than 99 wt.% carbon is found. Carbonization is often exothermic, which means that it could in principle be made self-sustaining and be used as a sou ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pesticide
Pesticides are substances that are used to control pests. They include herbicides, insecticides, nematicides, fungicides, and many others (see table). The most common of these are herbicides, which account for approximately 50% of all pesticide use globally. Most pesticides are used as plant protection products (also known as crop protection products), which in general protect plants from weeds, fungi, or insects. In general, a pesticide is a chemical or biological agent (such as a virus, bacterium, or fungus) that deters, incapacitates, kills, or otherwise discourages pests. Target pests can include insects, plant pathogens, weeds, molluscs, birds, mammals, fish, nematodes (roundworms), and microbes that destroy property, cause nuisance, spread disease, or are disease vectors. Along with these benefits, pesticides also have drawbacks, such as potential toxicity to humans and other species. Definition The word pesticide derives from the Latin ''pestis'' (plagu ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
