1.
Cedrus libani
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Cedrus libani, commonly known as the Cedar of Lebanon is a species of cedar native to the mountains of the Eastern Mediterranean basin. It is a conifer that can reach 40 m in height. Cedrus libani is the emblem of Lebanon and is widely used as an ornamental tree in parks. Cedrus libani is a coniferous tree, it can reach 40 m in height with a massive monopodial columnar trunk up to 2.5 m in diameter. The trunks of old trees ordinarily fork into several large, erect branches, the rough and scaly bark is dark grey to blackish brown, it is run through by deep horizontal fissures that peel in small chips. The first-order branches are ascending in young trees, they grow to a size and take on a horizontal. Second-order branches are dense and grow in a horizontal plane, the crown is conical when young, becoming broadly tabular with age with fairly level branches, trees growing in dense forests maintain a more pyramidal shape. The shoots are dimorphic, with long and short shoots. New shoots are brown, older shoots turn grey, grooved. C. libani has slightly resinous ovoid vegetative buds measuring 2 to 3 mm long and 1.5 to 2 mm wide enclosed by pale brown deciduous scales. Cedrus libani produces cones at around the age of 40, it flowers in autumn, the male cones appear in early September and the female ones in late September. Male cones occur at the ends of the shoots, they are solitary and erect approximately 4 to 5 cm long. The female seed cones also grow at the ends of short shoots. The young seed cones are resinous, sessile and pale green, the mature woody cones are 8 to 12 cm long and 3 to 6 cm wide, they are scaly, resinous, ovoid or barrel shaped and gray-brown in color. Mature cones open from top to bottom, they disintegrate and lose their seed scales releasing the seeds until only the cone rachis remains attached to the branches. The seed scales are thin, broad and coriaceous measuring 3.5 to 4 cm long and 3 to 3.5 cm wide. The seeds are ovoid,10 to 14 mm long and 4 to 6 mm wide, Cedrus libani grows rapidly until the age of 45 to 50 years, growth becomes extremely slow after the age of 70 years. Cedrus is the Latin name for true cedars, the specific epithet refers the Lebanon mountain range where the species was first described by French botanist Achille Richard, the tree is commonly known as the Lebanon cedar or Cedar of Lebanon
2.
Mummy
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Some authorities restrict the use of the term to bodies deliberately embalmed with chemicals, but the use of the word to cover accidentally desiccated bodies goes back to at least 1615 CE. Mummies of humans and other animals have found on every continent. Over one million animal mummies have been found in Egypt, many of which are cats, in addition to the well-known mummies of ancient Egypt, deliberate mummification was a feature of several ancient cultures in areas of America and Asia with very dry climates. The Spirit Cave mummies of Fallon, Nevada in North America were accurately dated at more than 9,400 years old. Before this discovery, the oldest known deliberate mummy was a child, one of the Chinchorro mummies found in the Camarones Valley, Chile, which dates around 5050 BCE. The oldest known naturally mummified corpse is a severed head dated as 6,000 years old. These substances were defined as mummia, the OED defines a mummy as the body of a human being or animal embalmed as a preparation for burial, citing sources from 1615 CE onward. However, Chambers Cyclopædia and the Victorian zoologist Francis Trevelyan Buckland define a mummy as follows, also applied to the frozen carcase of an animal imbedded in prehistoric snow. Wasps of the genus Aleiodes are known as mummy wasps because they wrap their prey as mummies. While interest in the study of mummies dates as far back as Ptolemaic Greece, prior to this, many rediscovered mummies were sold as curiosities or for use in pseudoscientific novelties such as mummia. The first modern scientific examinations of mummies began in 1901, conducted by professors at the English-language Government School of Medicine in Cairo, Egypt. The first X-ray of a mummy came in 1903, when professors Grafton Elliot Smith, British chemist Alfred Lucas applied chemical analyses to Egyptian mummies during this same period, which returned many results about the types of substances used in embalming. Lucas also made significant contributions to the analysis of Tutankhamun in 1922, pathological study of mummies saw varying levels of popularity throughout the 20th century. In 1992, the First World Congress on Mummy Studies was held in Puerto de la Cruz on Tenerife in the Canary Islands, more than 300 scientists attended the Congress to share nearly 100 years of collected data on mummies. This was not possible prior to the Congress due to the unique, in more recent years, CT scanning has become an invaluable tool in the study of mummification by allowing researchers to digitally unwrap mummies without risking damage to the body. The level of detail in such scans is so intricate that small linens used in areas such as the nostrils can be digitally reconstructed in 3-D. Such modelling has been utilized to perform autopsies on mummies to determine cause of death and lifestyle. Mummies are typically divided into one of two categories, anthropogenic or spontaneous
3.
Pharaoh
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The word pharaoh ultimately derive from the Egyptian compound pr-ˤ3 great house, written with the two biliteral hieroglyphs pr house and ˤ3 column, here meaning great or high. It was used only in larger phrases such as smr pr-ˤ3 Courtier of the High House, with specific reference to the buildings of the court or palace. From the twelfth dynasty onward, the word appears in a wish formula Great House, may it live, prosper, and be in health, but again only with reference to the royal palace and not the person. During the reign of Thutmose III in the New Kingdom, after the rule of the Hyksos during the Second Intermediate Period. During the eighteenth dynasty the title pharaoh was employed as a designation of the ruler. From the nineteenth dynasty onward pr-ˤ3 on its own was used as regularly as hm. f, the term, therefore, evolved from a word specifically referring to a building to a respectful designation for the ruler, particularly by the twenty-second dynasty and twenty-third dynasty. For instance, the first dated appearance of the pharaoh being attached to a rulers name occurs in Year 17 of Siamun on a fragment from the Karnak Priestly Annals. Here, an induction of an individual to the Amun priesthood is dated specifically to the reign of Pharaoh Siamun and this new practice was continued under his successor Psusennes II and the twenty-second dynasty kings. Shoshenq I was the successor of Siamun. Meanwhile, the old custom of referring to the sovereign simply as pr-ˤ3 continued in traditional Egyptian narratives, by this time, the Late Egyptian word is reconstructed to have been pronounced *par-ʕoʔ whence Herodotus derived the name of one of the Egyptian kings, Φερων. In the Bible, the title also occurs as פרעה, from that, Septuagint φαραώ pharaō and then Late Latin pharaō, both -n stem nouns. The Quran likewise spells it فرعون firawn with n, interestingly, the Arabic combines the original pharyngeal ayin sound from Egyptian, along with the -n ending from Greek. English at first spelt it Pharao, but the King James Bible revived Pharaoh with h from the Hebrew, meanwhile in Egypt itself, *par-ʕoʔ evolved into Sahidic Coptic ⲡⲣ̅ⲣⲟ prro and then rro. Scepters and staves were a sign of authority in ancient Egypt. One of the earliest royal scepters was discovered in the tomb of Khasekhemwy in Abydos, kings were also known to carry a staff, and Pharaoh Anedjib is shown on stone vessels carrying a so-called mks-staff. The scepter with the longest history seems to be the heqa-scepter, the earliest examples of this piece of regalia dates to pre-dynastic times. A scepter was found in a tomb at Abydos that dates to the late Naqada period, another scepter associated with the king is the was-scepter. This is a long staff mounted with an animal head, the earliest known depictions of the was-scepter date to the first dynasty
4.
Insect
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Insects are a class of hexapod invertebrates within the arthropod phylum that have a chitinous exoskeleton, a three-part body, three pairs of jointed legs, compound eyes and one pair of antennae. They are the most diverse group of animals on the planet, including more than a million described species, the number of extant species is estimated at between six and ten million, and potentially represent over 90% of the differing animal life forms on Earth. Insects may be found in all environments, although only a small number of species reside in the oceans. The life cycles of insects vary but most hatch from eggs, insect growth is constrained by the inelastic exoskeleton and development involves a series of molts. The immature stages can differ from the adults in structure, habit and habitat, Insects that undergo 3-stage metamorphosis lack a pupal stage and adults develop through a series of nymphal stages. The higher level relationship of the Hexapoda is unclear, fossilized insects of enormous size have been found from the Paleozoic Era, including giant dragonflies with wingspans of 55 to 70 cm. The most diverse insect groups appear to have coevolved with flowering plants, adult insects typically move about by walking, flying or sometimes swimming. As it allows for rapid yet stable movement, many insects adopt a tripedal gait in which they walk with their legs touching the ground in alternating triangles, Insects are the only invertebrates to have evolved flight. Many insects spend at least part of their lives under water, with adaptations that include gills. Some species, such as water striders, are capable of walking on the surface of water, Insects are mostly solitary, but some, such as certain bees, ants and termites, are social and live in large, well-organized colonies. Some insects, such as earwigs, show maternal care, guarding their eggs, Insects can communicate with each other in a variety of ways. Male moths can sense the pheromones of female moths over great distances, other species communicate with sounds, crickets stridulate, or rub their wings together, to attract a mate and repel other males. Lampyridae in the beetle order communicate with light, humans regard certain insects as pests, and attempt to control them using insecticides and a host of other techniques. Some insects damage crops by feeding on sap, leaves or fruits, a few parasitic species are pathogenic. Some insects perform complex ecological roles, blow-flies, for example, help consume carrion, Many other insects are considered ecologically beneficial as predators and a few provide direct economic benefit. Silkworms and bees have been used extensively by humans for the production of silk and honey, in some cultures, people eat the larvae or adults of certain insects. Insect first appears documented in English in 1601 in Hollands translation of Pliny, translations of Aristotles term also form the usual word for insect in Welsh, Serbo-Croatian, Russian, etc. The evolutionary relationship of insects to other animal groups remains unclear, in the Pancrustacea theory, insects, together with Entognatha, Remipedia, and Cephalocarida, make up a natural clade labeled Miracrustacea
5.
Materials science
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The interdisciplinary field of materials science, also commonly termed materials science and engineering, involves the discovery and design of new materials, with an emphasis on solids. Materials science still incorporates elements of physics, chemistry, and engineering, as such, the field was long considered by academic institutions as a sub-field of these related fields. Materials science is a syncretic discipline hybridizing metallurgy, ceramics, solid-state physics and it is the first example of a new academic discipline emerging by fusion rather than fission. Many of the most pressing scientific problems humans currently face are due to the limits of the materials that are available, thus, breakthroughs in materials science are likely to affect the future of technology significantly. Materials scientists emphasize understanding how the history of a material influences its structure, the understanding of processing-structure-properties relationships is called the § materials paradigm. This paradigm is used to advance understanding in a variety of areas, including nanotechnology, biomaterials. Such investigations are key to understanding, for example, the causes of various accidents and incidents. The material of choice of a given era is often a defining point, phrases such as Stone Age, Bronze Age, Iron Age, and Steel Age are great examples. Originally deriving from the manufacture of ceramics and its putative derivative metallurgy, materials science is one of the oldest forms of engineering, modern materials science evolved directly from metallurgy, which itself evolved from mining and ceramics and the use of fire. Materials science has driven, and been driven by, the development of technologies such as rubbers, plastics, semiconductors. Before the 1960s, many materials science departments were named metallurgy departments, reflecting the 19th, a material is defined as a substance that is intended to be used for certain applications. There are a myriad of materials around us—they can be found in anything from buildings to spacecraft, Materials can generally be divided into two classes, crystalline and non-crystalline. The traditional examples of materials are metals, semiconductors, ceramics, New and advanced materials that are being developed include nanomaterials and biomaterials, etc. The basis of science involves studying the structure of materials. Once a materials scientist knows about this structure-property correlation, they can go on to study the relative performance of a material in a given application. The major determinants of the structure of a material and thus of its properties are its constituent chemical elements and these characteristics, taken together and related through the laws of thermodynamics and kinetics, govern a materials microstructure, and thus its properties. As mentioned above, structure is one of the most important components of the field of materials science, Materials science examines the structure of materials from the atomic scale, all the way up to the macro scale. Characterization is the way materials scientists examine the structure of a material, structure is studied at various levels, as detailed below
6.
Viscosity
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The viscosity of a fluid is a measure of its resistance to gradual deformation by shear stress or tensile stress. For liquids, it corresponds to the concept of thickness, for example. Viscosity is a property of the fluid which opposes the motion between the two surfaces of the fluid in a fluid that are moving at different velocities. For a given velocity pattern, the stress required is proportional to the fluids viscosity, a fluid that has no resistance to shear stress is known as an ideal or inviscid fluid. Zero viscosity is observed only at low temperatures in superfluids. Otherwise, all fluids have positive viscosity, and are said to be viscous or viscid. A fluid with a high viscosity, such as pitch. The word viscosity is derived from the Latin viscum, meaning mistletoe, the dynamic viscosity of a fluid expresses its resistance to shearing flows, where adjacent layers move parallel to each other with different speeds. It can be defined through the situation known as a Couette flow. This fluid has to be homogeneous in the layer and at different shear stresses, if the speed of the top plate is small enough, the fluid particles will move parallel to it, and their speed will vary linearly from zero at the bottom to u at the top. Each layer of fluid will move faster than the one just below it, in particular, the fluid will apply on the top plate a force in the direction opposite to its motion, and an equal but opposite one to the bottom plate. An external force is required in order to keep the top plate moving at constant speed. The magnitude F of this force is found to be proportional to the u and the area A of each plate. The proportionality factor μ in this formula is the viscosity of the fluid, the ratio u/y is called the rate of shear deformation or shear velocity, and is the derivative of the fluid speed in the direction perpendicular to the plates. Isaac Newton expressed the forces by the differential equation τ = μ ∂ u ∂ y, where τ = F/A. This formula assumes that the flow is moving along parallel lines and this equation can be used where the velocity does not vary linearly with y, such as in fluid flowing through a pipe. Use of the Greek letter mu for the dynamic viscosity is common among mechanical and chemical engineers. However, the Greek letter eta is used by chemists, physicists
7.
Polymer
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A polymer is a large molecule, or macromolecule, composed of many repeated subunits. Because of their range of properties, both synthetic and natural polymers play an essential and ubiquitous role in everyday life. Polymers range from familiar synthetic plastics such as polystyrene to natural biopolymers such as DNA and proteins that are fundamental to biological structure, Polymers, both natural and synthetic, are created via polymerization of many small molecules, known as monomers. The units composing polymers derive, actually or conceptually, from molecules of low molecular mass. The term was coined in 1833 by Jöns Jacob Berzelius, though with a distinct from the modern IUPAC definition. The modern concept of polymers as covalently bonded macromolecular structures was proposed in 1920 by Hermann Staudinger, Polymers are studied in the fields of biophysics and macromolecular science, and polymer science. Polyisoprene of latex rubber is an example of a polymer. In biological contexts, essentially all biological macromolecules—i. e, proteins, nucleic acids, and polysaccharides—are purely polymeric, or are composed in large part of polymeric components—e. g. Isoprenylated/lipid-modified glycoproteins, where small molecules and oligosaccharide modifications occur on the polyamide backbone of the protein. The simplest theoretical models for polymers are ideal chains, Polymers are of two types, Natural polymeric materials such as shellac, amber, wool, silk and natural rubber have been used for centuries. A variety of natural polymers exist, such as cellulose. Most commonly, the continuously linked backbone of a used for the preparation of plastics consists mainly of carbon atoms. A simple example is polyethylene, whose repeating unit is based on ethylene monomer, however, other structures do exist, for example, elements such as silicon form familiar materials such as silicones, examples being Silly Putty and waterproof plumbing sealant. Oxygen is also present in polymer backbones, such as those of polyethylene glycol, polysaccharides. Polymerization is the process of combining many small molecules known as monomers into a covalently bonded chain or network, during the polymerization process, some chemical groups may be lost from each monomer. This is the case, for example, in the polymerization of PET polyester, the distinct piece of each monomer that is incorporated into the polymer is known as a repeat unit or monomer residue. Laboratory synthetic methods are divided into two categories, step-growth polymerization and chain-growth polymerization. However, some methods such as plasma polymerization do not fit neatly into either category
8.
Organic compound
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An organic compound is virtually any chemical compound that contains carbon, although a consensus definition remains elusive and likely arbitrary. Organic compounds are rare terrestrially, but of importance because all known life is based on organic compounds. The most basic petrochemicals are considered the building blocks of organic chemistry, for historical reasons discussed below, a few types of carbon-containing compounds, such as carbides, carbonates, simple oxides of carbon, and cyanides are considered inorganic. The distinction between organic and inorganic compounds, while useful in organizing the vast subject of chemistry. Organic chemistry is the science concerned with all aspects of organic compounds, Organic synthesis is the methodology of their preparation. The word organic is historical, dating to the 1st century, for many centuries, Western alchemists believed in vitalism. This is the theory that certain compounds could be synthesized only from their classical elements—earth, water, air, vitalism taught that these organic compounds were fundamentally different from the inorganic compounds that could be obtained from the elements by chemical manipulation. Vitalism survived for a while even after the rise of modern atomic theory and it first came under question in 1824, when Friedrich Wöhler synthesized oxalic acid, a compound known to occur only in living organisms, from cyanogen. A more decisive experiment was Wöhlers 1828 synthesis of urea from the inorganic salts potassium cyanate, urea had long been considered an organic compound, as it was known to occur only in the urine of living organisms. Wöhlers experiments were followed by others, in which increasingly complex organic substances were produced from inorganic ones without the involvement of any living organism. Even though vitalism has been discredited, scientific nomenclature retains the distinction between organic and inorganic compounds, still, even the broadest definition requires excluding alloys that contain carbon, including steel. The C-H definition excludes compounds that are considered organic, neither urea nor oxalic acid is organic by this definition, yet they were two key compounds in the vitalism debate. The IUPAC Blue Book on organic nomenclature specifically mentions urea and oxalic acid, other compounds lacking C-H bonds but traditionally considered organic include benzenehexol, mesoxalic acid, and carbon tetrachloride. Mellitic acid, which contains no C-H bonds, is considered an organic substance in Martian soil. The C-H bond-only rule also leads to somewhat arbitrary divisions in sets of carbon-fluorine compounds, for example, CF4 would be considered by this rule to be inorganic, whereas CF3H would be organic. Organic compounds may be classified in a variety of ways, one major distinction is between natural and synthetic compounds. Another distinction, based on the size of organic compounds, distinguishes between small molecules and polymers, natural compounds refer to those that are produced by plants or animals. Many of these are extracted from natural sources because they would be more expensive to produce artificially
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