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Hendrik Zwaardemaker
Hendrik Zwaardemaker ( – ) was a Dutch scientist who invented the olfactometer in 1888. From 1897 to 1927 he was professor of Experimental Physiology at the University of Utrecht. In 1903 he became member of the Royal Netherlands Academy of Arts and Sciences. In addition to his work on the sense of smell, he also conducted research on the human heart. He found that salts of potassium and other radioactive elements stimulated the heart. His major work was "Die Physiologie des Geruchs" (Physiologie of Olfaction), it appeared in 1895. Zwaardemaker Pairs An important contribution of Zwaardemaker's studies is the concept of odor conjugates. Zwaardemaker discovered that certain odors could be prevented from detection by smell senses when mixed with various essential oils An essential oil is a concentrated hydrophobic liquid containing volatile (easily evaporated at normal temperatures) chemical compounds from plants. Essential oils are also known as volatile oils, etherea ...
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Haarlem, Netherlands
Haarlem (; predecessor of ''Harlem'' in English) is a city and municipality in the Netherlands. It is the capital of the province of North Holland. Haarlem is situated at the northern edge of the Randstad, one of the most populated metropolitan areas in Europe; it is also part of the Amsterdam metropolitan area, being located about 15 km to the west of the core city of Amsterdam. Haarlem had a population of in . Haarlem was granted city status or '' stadsrechten'' in 1245, although the first city walls were not built until 1270. The modern city encompasses the former municipality of Schoten as well as parts that previously belonged to Bloemendaal and Heemstede. Apart from the city, the municipality of Haarlem also includes the western part of the village of Spaarndam. Newer sections of Spaarndam lie within the neighbouring municipality of Haarlemmermeer. Geography Haarlem is located on the river Spaarne, giving it its nickname 'Spaarnestad' (Spaarne city). It is situated ...
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Flesh
Flesh is any aggregation of soft tissues of an organism. Various multicellular organisms have soft tissues that may be called "flesh". In mammals, including humans, ''flesh'' encompasses muscle Skeletal muscles (commonly referred to as muscles) are organs of the vertebrate muscular system and typically are attached by tendons to bones of a skeleton. The muscle cells of skeletal muscles are much longer than in the other types of muscl ...s, adipose tissue, fats and other loose connective tissues, but sometimes excluding non-muscular viscera, organs (liver, lung, spleen, kidney) and typically slaughterhouse waste, discarded parts (hard tendon, brain tissue, intestines, etc.). In a culinary context, consumable animal flesh is called meat, while processed visceral tissues are known as offal. In particular animal groups such as vertebrates, molluscs and arthropods, the flesh is distinguished from tougher body structures such as bone, exoskeleton, shell and scute, respectively ...
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Cigarette
A cigarette is a narrow cylinder containing a combustible material, typically tobacco, that is rolled into thin paper for smoking. The cigarette is ignited at one end, causing it to smolder; the resulting smoke is orally inhaled via the opposite end. Cigarette smoking is the most common method of tobacco consumption. The term ''cigarette'', as commonly used, refers to a tobacco cigarette, but the word is sometimes used to refer to other substances, such as a cannabis cigarette or an herbal cigarette. A cigarette is distinguished from a cigar by its usually smaller size, use of processed leaf, and paper wrapping, which is typically white. Since the 1920s, scientists and doctors have been able to link smoking with respiratory illness. Researchers have identified negative health effects from smoking cigarettes such as cancer, chronic obstructive pulmonary disease (COPD), heart disease, and other health problems relating to nearly every organ of the body. Nicotine, the psycho ...
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Tobacco
Tobacco is the common name of several plants in the genus '' Nicotiana'' of the family Solanaceae, and the general term for any product prepared from the cured leaves of these plants. More than 70 species of tobacco are known, but the chief commercial crop is ''N. tabacum''. The more potent variant ''N. rustica'' is also used in some countries. Dried tobacco leaves are mainly used for smoking in cigarettes and cigars, as well as pipes and shishas. They can also be consumed as snuff, chewing tobacco, dipping tobacco, and snus. Tobacco contains the highly addictive stimulant alkaloid nicotine as well as harmala alkaloids. Tobacco use is a cause or risk factor for many deadly diseases, especially those affecting the heart, liver, and lungs, as well as many cancers. In 2008, the World Health Organization named tobacco use as the world's single greatest preventable cause of death. Etymology The English word ''tobacco'' originates from the Spanish word "tabaco ...
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Ionone
The ionones are a series of closely related chemical substances that are part of a group of compounds known as rose ketones, which also includes damascones and damascenones. Ionones are aroma compounds found in a variety of essential oils, including rose oil. β-Ionone is a significant contributor to the aroma of roses, despite its relatively low concentration, and is an important fragrance chemical used in perfumery. The ionones are derived from the degradation of carotenoids. The combination of α-ionone and β-ionone is characteristic of the scent of violets and used with other components in perfumery and flavouring to recreate their scent. The carotenes α-carotene, β-carotene, γ-carotene, and the xanthophyll Xanthophylls (originally phylloxanthins) are yellow pigments that occur widely in nature and form one of two major divisions of the carotenoid group; the other division is formed by the carotenes. The name is from Greek (, "yellow") and (, "l ... β ...
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Rose Oil
Rose oil (rose otto, attar of rose, attar of roses, or rose essence) is the essential oil extracted from the petals of various types of rose. ''Rose ottos'' are extracted through steam distillation, while ''rose absolutes'' are obtained through solvent extraction, the absolute being used more commonly in perfumery. The production technique originated in Persia. Even with their high price and the advent of organic synthesis, rose oils are still perhaps the most widely used essential oil in perfumery. Components Two major species of rose are cultivated for the production of rose oil: * ''Rosa damascena'', the damask rose, which is widely grown in Bulgaria, Syria, Turkey, Russia, Pakistan, India, Uzbekistan, Iran and China * ''Rosa centifolia'', the cabbage rose, which is more commonly grown in Morocco, France and Egypt. The most common chemical compounds present in rose oil are: citronellol, geraniol, nerol, linalool, phenyl ethyl alcohol, farnesol, stearoptene, α-pinene, β ...
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Urine
Urine is a liquid by-product of metabolism in humans and in many other animals. Urine flows from the kidneys through the ureters to the urinary bladder. Urination results in urine being excretion, excreted from the body through the urethra. Cell (biology), Cellular metabolism generates many by-products that are rich in nitrogen and must be clearance (medicine), cleared from the Circulatory system, bloodstream, such as urea, uric acid, and creatinine. These by-products are expelled from the body during urination, which is the primary method for excreting water-soluble chemicals from the body. A urinalysis can detect nitrogenous wastes of the mammalian body. Urine plays an important role in the earth's nitrogen cycle. In balanced ecosystems, urine fertilizes the soil and thus helps plants to grow. Therefore, Reuse of excreta, urine can be used as a fertilizer. Some animals use it to territory (animal)#Scent marking, mark their territories. Historically, aged or fermented urine (kn ...
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Ammonia
Ammonia is an inorganic compound of nitrogen and hydrogen with the formula . A stable binary hydride, and the simplest pnictogen hydride, ammonia is a colourless gas with a distinct pungent smell. Biologically, it is a common nitrogenous waste, particularly among aquatic organisms, and it contributes significantly to the nutritional needs of terrestrial organisms by serving as a precursor to 45% of the world's food and fertilizers. Around 70% of ammonia is used to make fertilisers in various forms and composition, such as urea and Diammonium phosphate. Ammonia in pure form is also applied directly into the soil. Ammonia, either directly or indirectly, is also a building block for the synthesis of many pharmaceutical products and is used in many commercial cleaning products. It is mainly collected by downward displacement of both air and water. Although common in nature—both terrestrially and in the outer planets of the Solar System—and in wide use, ammonia is both caust ...
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Vanillin
Vanillin is an organic compound with the molecular formula . It is a phenolic aldehyde. Its functional groups include aldehyde, hydroxyl, and ether. It is the primary component of the extract of the vanilla bean. Synthetic vanillin is now used more often than natural vanilla extract as a flavoring in foods, beverages, and pharmaceuticals. Vanillin and ethylvanillin are used by the food industry; ethylvanillin is more expensive, but has a stronger note. It differs from vanillin by having an ethoxy group (−O−CH2CH3) instead of a methoxy group (−O−CH3). Natural vanilla extract is a mixture of several hundred different compounds in addition to vanillin. Artificial vanilla flavoring is often a solution of pure vanillin, usually of synthetic origin. Because of the scarcity and expense of natural vanilla extract, synthetic preparation of its predominant component has long been of interest. The first commercial synthesis of vanillin began with the more readily available na ...
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Vanilla
Vanilla is a spice derived from orchids of the genus ''Vanilla (genus), Vanilla'', primarily obtained from pods of the Mexican species, flat-leaved vanilla (''Vanilla planifolia, V. planifolia''). Pollination is required to make the plants produce the fruit from which the vanilla spice is obtained. In 1837, Belgian botanist Charles François Antoine Morren discovered this fact and pioneered a method of artificially pollinating the plant. The method proved financially unworkable and was not deployed commercially. In 1841, Edmond Albius, a 12-year-old enslaved child who lived on the French island of Réunion in the Indian Ocean, discovered that the plant could be hand-pollination, hand-pollinated. Hand-pollination allowed global cultivation of the plant. Noted French botanist and plant collector Jean Michel Claude Richard falsely claimed to have discovered the technique three or four years earlier. By the end of the 20th century, Albius was considered the true discoverer ...
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Chlorine
Chlorine is a chemical element with the Symbol (chemistry), symbol Cl and atomic number 17. The second-lightest of the halogens, it appears between fluorine and bromine in the periodic table and its properties are mostly intermediate between them. Chlorine is a yellow-green gas at room temperature. It is an extremely reactive element and a strong oxidising agent: among the elements, it has the highest electron affinity and the third-highest electronegativity on the revised Electronegativity#Pauling electronegativity, Pauling scale, behind only oxygen and fluorine. Chlorine played an important role in the experiments conducted by medieval Alchemy, alchemists, which commonly involved the heating of chloride Salt (chemistry), salts like ammonium chloride (sal ammoniac) and sodium chloride (common salt), producing various chemical substances containing chlorine such as hydrogen chloride, mercury(II) chloride (corrosive sublimate), and hydrochloric acid (in the form of ). However ...
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Juniper
Junipers are coniferous trees and shrubs in the genus ''Juniperus'' () of the cypress family Cupressaceae. Depending on the taxonomy, between 50 and 67 species of junipers are widely distributed throughout the Northern Hemisphere, from the Arctic, south to tropical Africa, throughout parts of West Asia, western, Central Asia, central and South Asia, southern Asia, east to eastern Tibet in the Old World, and in the mountains of Central America. The highest-known juniper forest occurs at an altitude of in southeastern Tibet and the northern Himalayas, creating one of the highest tree lines on earth. Description Junipers vary in size and shape from tall trees, tall, to columnar or low-spreading shrubs with long, trailing branches. They are evergreen with needle-like and/or scale-like leaves. They can be either monoecious or dioecious. The female Conifer cone, seed cones are very distinctive, with fleshy, fruit-like coalescing scales which fuse together to form Juniper berry, a&n ...
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