1.
Compact disc
–
Compact disc is a digital optical disc data storage format released in 1982 and co-developed by Philips and Sony. The format was developed to store and play only sound recordings but was later adapted for storage of data. The first commercially available Audio CD player, the Sony CDP-101, was released October 1982 in Japan, standard CDs have a diameter of 120 millimetres and can hold up to about 80 minutes of uncompressed audio or about 700 MiB of data. The Mini CD has various diameters ranging from 60 to 80 millimetres, they are used for CD singles, storing up to 24 minutes of audio. At the time of the introduction in 1982, a CD could store much more data than a personal computer hard drive. By 2010, hard drives commonly offered as much space as a thousand CDs. In 2004, worldwide sales of audio CDs, CD-ROMs and CD-Rs reached about 30 billion discs, by 2007,200 billion CDs had been sold worldwide. In 2014, revenues from digital music services matched those from physical format sales for the first time. American inventor James T. Russell has been credited with inventing the first system to record information on an optical transparent foil that is lit from behind by a high-power halogen lamp. Russells patent application was first filed in 1966, and he was granted a patent in 1970, following litigation, Sony and Philips licensed Russells patents in the 1980s. The compact disc is an evolution of LaserDisc technology, where a laser beam is used that enables the high information density required for high-quality digital audio signals. Prototypes were developed by Philips and Sony independently in the late 1970s, although originally dismissed by Philips Research management as a trivial pursuit, the CD became the primary focus for Philips as the LaserDisc format struggled. In 1979, Sony and Philips set up a joint task force of engineers to design a new audio disc. After a year of experimentation and discussion, the Red Book CD-DA standard was published in 1980, after their commercial release in 1982, compact discs and their players were extremely popular. Despite costing up to $1,000, over 400,000 CD players were sold in the United States between 1983 and 1984, by 1988 CD sales in the United States surpassed those of vinyl LPs, and by 1992 CD sales surpassed those of prerecorded music cassette tapes. The success of the disc has been credited to the cooperation between Philips and Sony, who came together to agree upon and develop compatible hardware. The unified design of the disc allowed consumers to purchase any disc or player from any company. In 1974, L. However, due to the performance of the analog format
Compact disc
–
The pits in a CD are 500
nm wide, between 830 nm and 3,000 nm long and 150 nm deep
Compact disc
Compact disc
–
700
MiB CD-R next to a
mechanical pencil
2.
Iridescence
–
Iridescence is the phenomenon of certain surfaces that appear to gradually change colour as the angle of view or the angle of illumination changes. Examples of iridescence include soap bubbles, butterfly wings and sea shells and it is often created by structural coloration. The word iridescence is derived in part from the Greek word ἶρις îris, meaning rainbow, Iris in turn derives from the goddess Iris of Greek mythology, who is the personification of the rainbow and acted as a messenger of the gods. Goniochromism is derived from the Greek words gonia, meaning angle, iridescence is an optical phenomenon of surfaces in which hue changes with the angle of observation and the angle of illumination. It is often caused by reflections from two or more semi-transparent surfaces in which phase shift and interference of the reflections modulates the incidental light. The thickness of the layers of the material determines the interference pattern, iridescence is also found in plants, animals and many other items. The range of colours of natural iridescent objects can be narrow, iridescence can also be created by diffraction. This is found in items like CDs, DVDs, or cloud iridescence, in the case of diffraction, the entire rainbow of colours will typically be observed as the viewing angle changes. In biology, this type of results from the formation of diffraction gratings on the surface. In biological uses, colours produced other than with pigments or dyes are called structural coloration and it was later found that iridescence in the peacock is due to a complex photonic crystal. The feathers of birds such as kingfishers, Birds-of-paradise, hummingbirds, parrots, starlings, grackles, ducks, the lateral line on the Neon tetra is also iridescent. A single iridescent species of gecko, Cnemaspis kolhapurensis, was identified in India in 2009, the tapetum lucidum, present in the eyes of many vertebrates, is also iridescent. Many groups of plants have developed iridescence as an adaptation to use light in dark environments such as the lower levels of tropical forests. Nanocellulose is sometimes iridescent, as are films of gasoline and some other hydrocarbons. Iridescent products in the cosmetic and clothing industries are often referred as being holographic
Iridescence
–
Iridescence in
soap bubbles
Iridescence
–
Iridescent nightscape over
La Silla Observatory.
Iridescence
–
Fuel on top of water creates a thin film, which interferes with the light, producing different colours. The different bands represent different thicknesses in the film.
Iridescence
–
An iridescent
biofilm on the surface of a fishtank diffracts the reflected light, displaying the entire spectrum of colours. Red is seen from longer angles of incidence than blue.
3.
Computing
–
Computing is any goal-oriented activity requiring, benefiting from, or creating a mathematical sequence of steps known as an algorithm — e. g. through computers. The field of computing includes computer engineering, software engineering, computer science, information systems, the ACM Computing Curricula 2005 defined computing as follows, In a general way, we can define computing to mean any goal-oriented activity requiring, benefiting from, or creating computers. For example, an information systems specialist will view computing somewhat differently from a software engineer, regardless of the context, doing computing well can be complicated and difficult. Because society needs people to do computing well, we must think of computing not only as a profession, the fundamental question underlying all computing is What can be automated. The term computing is also synonymous with counting and calculating, in earlier times, it was used in reference to the action performed by mechanical computing machines, and before that, to human computers. Computing is intimately tied to the representation of numbers, but long before abstractions like the number arose, there were mathematical concepts to serve the purposes of civilization. These concepts include one-to-one correspondence, comparison to a standard, the earliest known tool for use in computation was the abacus, and it was thought to have been invented in Babylon circa 2400 BC. Its original style of usage was by lines drawn in sand with pebbles, abaci, of a more modern design, are still used as calculation tools today. This was the first known computer and most advanced system of calculation known to date - preceding Greek methods by 2,000 years. The first recorded idea of using electronics for computing was the 1931 paper The Use of Thyratrons for High Speed Automatic Counting of Physical Phenomena by C. E. Wynn-Williams. Claude Shannons 1938 paper A Symbolic Analysis of Relay and Switching Circuits then introduced the idea of using electronics for Boolean algebraic operations, a computer is a machine that manipulates data according to a set of instructions called a computer program. The program has a form that the computer can use directly to execute the instructions. The same program in its source code form, enables a programmer to study. Because the instructions can be carried out in different types of computers, the execution process carries out the instructions in a computer program. Instructions express the computations performed by the computer and they trigger sequences of simple actions on the executing machine. Those actions produce effects according to the semantics of the instructions, computer software or just software, is a collection of computer programs and related data that provides the instructions for telling a computer what to do and how to do it. Software refers to one or more programs and data held in the storage of the computer for some purposes. In other words, software is a set of programs, procedures, algorithms, program software performs the function of the program it implements, either by directly providing instructions to the computer hardware or by serving as input to another piece of software
Computing
–
A
difference engine: computing the solution to a
polynomial function
Computing
–
Computer laboratory, Moody Hall, James Madison University, 2003
Computing
–
A rack of
servers from 2006
4.
Compact disk
–
Compact disc is a digital optical disc data storage format released in 1982 and co-developed by Philips and Sony. The format was developed to store and play only sound recordings but was later adapted for storage of data. The first commercially available Audio CD player, the Sony CDP-101, was released October 1982 in Japan, standard CDs have a diameter of 120 millimetres and can hold up to about 80 minutes of uncompressed audio or about 700 MiB of data. The Mini CD has various diameters ranging from 60 to 80 millimetres, they are used for CD singles, storing up to 24 minutes of audio. At the time of the introduction in 1982, a CD could store much more data than a personal computer hard drive. By 2010, hard drives commonly offered as much space as a thousand CDs. In 2004, worldwide sales of audio CDs, CD-ROMs and CD-Rs reached about 30 billion discs, by 2007,200 billion CDs had been sold worldwide. In 2014, revenues from digital music services matched those from physical format sales for the first time. American inventor James T. Russell has been credited with inventing the first system to record information on an optical transparent foil that is lit from behind by a high-power halogen lamp. Russells patent application was first filed in 1966, and he was granted a patent in 1970, following litigation, Sony and Philips licensed Russells patents in the 1980s. The compact disc is an evolution of LaserDisc technology, where a laser beam is used that enables the high information density required for high-quality digital audio signals. Prototypes were developed by Philips and Sony independently in the late 1970s, although originally dismissed by Philips Research management as a trivial pursuit, the CD became the primary focus for Philips as the LaserDisc format struggled. In 1979, Sony and Philips set up a joint task force of engineers to design a new audio disc. After a year of experimentation and discussion, the Red Book CD-DA standard was published in 1980, after their commercial release in 1982, compact discs and their players were extremely popular. Despite costing up to $1,000, over 400,000 CD players were sold in the United States between 1983 and 1984, by 1988 CD sales in the United States surpassed those of vinyl LPs, and by 1992 CD sales surpassed those of prerecorded music cassette tapes. The success of the disc has been credited to the cooperation between Philips and Sony, who came together to agree upon and develop compatible hardware. The unified design of the disc allowed consumers to purchase any disc or player from any company. In 1974, L. However, due to the performance of the analog format
Compact disk
–
The pits in a CD are 500
nm wide, between 830 nm and 3,000 nm long and 150 nm deep
Compact disk
–
Compact disc
Compact disk
–
700
MiB CD-R next to a
mechanical pencil
5.
Aluminium
–
Aluminium or aluminum is a chemical element in the boron group with symbol Al and atomic number 13. It is a silvery-white, soft, nonmagnetic, ductile metal, Aluminium metal is so chemically reactive that native specimens are rare and limited to extreme reducing environments. Instead, it is combined in over 270 different minerals. The chief ore of aluminium is bauxite, Aluminium is remarkable for the metals low density and its ability to resist corrosion through the phenomenon of passivation. Aluminium and its alloys are vital to the industry and important in transportation and structures, such as building facades. The oxides and sulfates are the most useful compounds of aluminium, despite its prevalence in the environment, no known form of life uses aluminium salts metabolically, but aluminium is well tolerated by plants and animals. Because of these salts abundance, the potential for a role for them is of continuing interest. Aluminium is a soft, durable, lightweight, ductile. It is nonmagnetic and does not easily ignite, a fresh film of aluminium serves as a good reflector of visible light and an excellent reflector of medium and far infrared radiation. The yield strength of aluminium is 7–11 MPa, while aluminium alloys have yield strengths ranging from 200 MPa to 600 MPa. Aluminium has about one-third the density and stiffness of steel and it is easily machined, cast, drawn and extruded. Aluminium atoms are arranged in a cubic structure. Aluminium has an energy of approximately 200 mJ/m2. Aluminium is a thermal and electrical conductor, having 59% the conductivity of copper. Aluminium is capable of superconductivity, with a critical temperature of 1.2 kelvin. Aluminium is the most common material for the fabrication of superconducting qubits, the strongest aluminium alloys are less corrosion resistant due to galvanic reactions with alloyed copper. This corrosion resistance is reduced by aqueous salts, particularly in the presence of dissimilar metals. In highly acidic solutions, aluminium reacts with water to form hydrogen, primarily because it is corroded by dissolved chlorides, such as common sodium chloride, household plumbing is never made from aluminium
Aluminium
–
Aluminium, 13 Al
Aluminium
–
Spectral lines of aluminium
Aluminium
–
"
Red mud " storage facility in
Stade,
Germany. The aluminium industry generates about 70 million tons of this waste annually.
Aluminium
–
Bauxite, a major aluminium ore. The red-brown color is due to the presence of
iron minerals.
6.
Polycarbonate
–
Polycarbonates are a group of thermoplastic polymers containing carbonate groups in their chemical structures. Polycarbonates used in engineering are strong, tough materials, and some grades are optically transparent and they are easily worked, molded, and thermoformed. Because of these properties, polycarbonates find many applications, Polycarbonates do not have a unique resin identification code and are identified as Other,7 on the RIC list. Products made from polycarbonate can contain the precursor monomer bisphenol A. Polycarbonates received their name because they are polymers containing carbonate groups, a balance of useful features, including temperature resistance, impact resistance and optical properties, positions polycarbonates between commodity plastics and engineering plastics. The main polycarbonate material is produced by the reaction of bisphenol A, the net reaction from the diphenoxide is, Na22CMe2 + COCl2 → 1/n n +2 NaCl In this way, approximately one billion kilograms of polycarbonate is produced annually. Many other diols have been tested in place of bisphenol A, e. g.1, the cyclohexane is used as a comonomer to suppress crystallisation tendency of the BPA-derived product. Tetrabromobisphenol A is used to enhance fire resistance, tetramethylcyclobutanediol has been developed as a replacement for BPA. Although it has high impact-resistance, it has low scratch-resistance, therefore, a hard coating is applied to polycarbonate eyewear lenses and polycarbonate exterior automotive components. The characteristics of polycarbonate compare to those of polymethyl methacrylate, but polycarbonate is stronger, Polycarbonate is highly transparent to visible light, with better light transmission than many kinds of glass. Polycarbonate has a transition temperature of about 147 °C, so it softens gradually above this point. Tools must be held at high temperatures, generally above 80 °C to make strain-free and stress-free products, low molecular mass grades are easier to mold than higher grades, but their strength is lower as a result. The toughest grades have the highest molecular mass, but are more difficult to process. Unlike most thermoplastics, polycarbonate can undergo plastic deformations without cracking or breaking. As a result, it can be processed and formed at room temperature using sheet metal techniques, even for sharp angle bends with a tight radius, heating may not be necessary. This makes it valuable in prototyping applications where transparent or electrically non-conductive parts are needed, pMMA/Acrylic, which is similar in appearance to polycarbonate, is brittle and cannot be bent at room temperature. Due to its chemical properties it is not conducive to laser-cutting, Injection molding into ready articles Polycarbonate may become brittle when exposed to ionizing radiation above 25 kGy. Polycarbonate is mainly used for applications that capitalize on its collective safety features. Being a good insulator and having heat-resistant and flame-retardant properties, it is used in various products associated with electrical
Polycarbonate
–
A bottle made from polycarbonate
Polycarbonate
Polycarbonate
–
Polycarbonate sheeting in a greenhouse
Polycarbonate
–
CDs and DVDs
7.
Laser
–
A laser is a device that emits light through a process of optical amplification based on the stimulated emission of electromagnetic radiation. The term laser originated as an acronym for light amplification by stimulated emission of radiation, the first laser was built in 1960 by Theodore H. Maiman at Hughes Research Laboratories, based on theoretical work by Charles Hard Townes and Arthur Leonard Schawlow. A laser differs from other sources of light in that it emits light coherently, spatial coherence allows a laser to be focused to a tight spot, enabling applications such as laser cutting and lithography. Spatial coherence also allows a laser beam to stay narrow over great distances, Lasers can also have high temporal coherence, which allows them to emit light with a very narrow spectrum, i. e. they can emit a single color of light. Temporal coherence can be used to produce pulses of light as short as a femtosecond, Lasers are distinguished from other light sources by their coherence. Spatial coherence is typically expressed through the output being a narrow beam, Laser beams can be focused to very tiny spots, achieving a very high irradiance, or they can have very low divergence in order to concentrate their power at a great distance. Temporal coherence implies a polarized wave at a single frequency whose phase is correlated over a great distance along the beam. A beam produced by a thermal or other incoherent light source has an amplitude and phase that vary randomly with respect to time and position. Lasers are characterized according to their wavelength in a vacuum, most single wavelength lasers actually produce radiation in several modes having slightly differing frequencies, often not in a single polarization. Although temporal coherence implies monochromaticity, there are lasers that emit a broad spectrum of light or emit different wavelengths of light simultaneously, there are some lasers that are not single spatial mode and consequently have light beams that diverge more than is required by the diffraction limit. However, all devices are classified as lasers based on their method of producing light. Lasers are employed in applications where light of the spatial or temporal coherence could not be produced using simpler technologies. The word laser started as an acronym for light amplification by stimulated emission of radiation, in the early technical literature, especially at Bell Telephone Laboratories, the laser was called an optical maser, this term is now obsolete. A laser that produces light by itself is technically an optical rather than an optical amplifier as suggested by the acronym. It has been noted that the acronym LOSER, for light oscillation by stimulated emission of radiation. With the widespread use of the acronym as a common noun, optical amplifiers have come to be referred to as laser amplifiers. The back-formed verb to lase is frequently used in the field, meaning to produce light, especially in reference to the gain medium of a laser. Further use of the laser and maser in an extended sense, not referring to laser technology or devices, can be seen in usages such as astrophysical maser
Laser
–
United States Air Force laser experiment
Laser
–
Red (660 & 635 nm), green (532 & 520 nm) and blue-violet (445 & 405 nm) lasers
Laser
–
Laser beams in fog, reflected on a car windshield
Laser
8.
Laser diode
–
A laser diode is electrically a PIN diode. The active region of the diode is in the intrinsic region. Unlike a regular diode, the goal for a diode is to recombine all carriers in the I region. Thus, laser diodes are fabricated using direct bandgap semiconductors, the active layer most often consists of quantum wells, which provide lower threshold current and higher efficiency. Laser diodes form a subset of the classification of semiconductor p-n junction diodes. Forward electrical bias across the laser diode causes the two species of charge carrier – holes and electrons – to be injected from opposite sides of the p-n junction into the depletion region, holes are injected from the p-doped, and electrons from the n-doped, semiconductor. Due to the use of injection in powering most diode lasers. As diode lasers are semiconductor devices, they may also be classified as semiconductor lasers, either designation distinguishes diode lasers from solid-state lasers. Another method of powering some diode lasers is the use of optical pumping, optically pumped semiconductor lasers use a III-V semiconductor chip as the gain medium, and another laser as the pump source. OPSL offer several advantages over ILDs, particularly in wavelength selection, spontaneous emission below the lasing threshold produces similar properties to an LED. Spontaneous emission is necessary to initiate laser oscillation, but it is one among several sources of inefficiency once the laser is oscillating and these photon-emitting semiconductors are the so-called direct bandgap semiconductors. The properties of silicon and germanium, which are single-element semiconductors, have bandgaps that do not align in the way needed to allow photon emission and are not considered direct, the transition between the materials in the alternating pattern creates the critical direct bandgap property. Gallium arsenide, indium phosphide, gallium antimonide, and gallium nitride are all examples of compound semiconductor materials that can be used to create junction diodes that emit light, a nearby photon with energy equal to the recombination energy can cause recombination by stimulated emission. This generates another photon of the frequency, polarization, and phase. This means that stimulated emission will cause gain in a wave in the injection region. As in other lasers, the region is surrounded with an optical cavity to form a laser. In the simplest form of diode, an optical waveguide is made on that crystals surface. The two ends of the crystal are cleaved to form smooth, parallel edges, forming a Fabry–Pérot resonator
Laser diode
–
Top: a packaged laser diode shown with a
penny for scale. Bottom: the laser diode chip is removed from the above package and placed on the eye of an orphan needle for scale.
Laser diode
Laser diode
–
A laser diode with the case cut away. The actual laser diode chip is the small black chip at the front; a photodiode at the back is used to control output power.
Laser diode
–
Semi-conductor lasers (660 nm, 635 nm, 532 nm, 520 nm, 445 nm, 405 nm)
9.
Optical disc drive
–
Some drives can only read from certain discs, but recent drives can both read and record, also called burners or writers. Compact discs, DVDs, and Blu-ray discs are common types of media which can be read. Optical disc drives that are no longer in production include CD-ROM drive, CD writer drive, combo drive, as of 2015, DVD writer drive supporting all existing recordable and rewritable DVD formats is the most common for desktop PCs and laptops. There are also the DVD-ROM drive, BD-ROM drive, Blu-ray Disc combo drive and they are also very commonly used in computers to read software and consumer media distributed on disc, and to record discs for archival and data exchange purposes. Floppy disk drives, with capacity of 1, USB flash drives, high-capacity, small, and inexpensive, are suitable where read/write capability is required. Large backups are often made on external hard drives, as their price has dropped to a level making this viable. The first laser disc, demonstrated in 1972, was the Laservision 12-inch video disc, the video signal was stored as an analog format like a video cassette. The first digitally recorded optical disc was a 5-inch audio compact disc in a format created by Sony. The CD-ROM format was developed by Sony and Denon, introduced in 1984, as an extension of Compact Disc Digital Audio, the CD-ROM has a storage capacity of 650 MB. Also in 1984, Sony introduced a LaserDisc data storage format, in 1987, Sony demonstrated the erasable and rewritable 5. 25-inch optical drive. The first Blu-Ray prototype was unveiled by Sony in October 2000, technically Blu-ray Disc also required a thinner layer for the narrower beam and shorter wavelength blue laser. The first BD-ROM players were shipped in mid-June 2006, the first Blu-ray Disc titles were released by Sony and MGM on June 20,2006. The first mass-market Blu-ray Disc rewritable drive for the PC was the BWU-100A, initially, CD-type lasers with a wavelength of 780 nm were used. For DVDs, the wavelength was reduced to 650 nm, two main servomechanisms are used, the first to maintain the proper distance between lens and disc, to ensure the laser beam is focused as a small laser spot on the disc. The second servo moves the head along the discs radius, keeping the beam on the track. Optical disk media are read beginning at the radius to the outer edge. This is detected by photodiodes that create corresponding electrical signals, an optical disk recorder encodes data onto a recordable CD-R, DVD-R, DVD+R, or BD-R disc by selectively heating parts of an organic dye layer with a laser. This changes the reflectivity of the dye, thereby creating marks that can be read like the pits, for recordable discs, the process is permanent and the media can be written to only once
Optical disc drive
–
A CD/DVD-ROM computer drive
Optical disc drive
–
An external
Apple USB
SuperDrive
Optical disc drive
–
The CD/DVD drive lens on an Acer laptop
Optical disc drive
–
A Blu-ray drive holds independent lenses for Blu-ray and DVD/CD media. Pictured are lenses from a Blu-ray writer in a Sony Vaio E series laptop
10.
Diffraction grating
–
In optics, a diffraction grating is an optical component with a periodic structure, which splits and diffracts light into several beams travelling in different directions. The emerging coloration is a form of structural coloration, the directions of these beams depend on the spacing of the grating and the wavelength of the light so that the grating acts as the dispersive element. Because of this, gratings are used in monochromators and spectrometers. For practical applications, gratings generally have ridges or rulings on their surface rather than dark lines, such gratings can be either transmissive or reflective. Gratings which modulate the phase rather than the amplitude of the incident light are also produced, the principles of diffraction gratings were discovered by James Gregory, about a year after Newtons prism experiments, initially with items such as bird feathers. The first man-made diffraction grating was made around 1785 by Philadelphia inventor David Rittenhouse and this was similar to notable German physicist Joseph von Fraunhofers wire diffraction grating in 1821. Diffraction can create rainbow colors when illuminated by a wide spectrum light source, a grating has parallel lines, while a CD has a spiral of finely-spaced data tracks. Diffraction colors also appear when one looks at a point source through a translucent fine-pitch umbrella-fabric covering. Decorative patterned plastic films based on reflective grating patches are very inexpensive, the relationship between the grating spacing and the angles of the incident and diffracted beams of light is known as the grating equation. Gratings may be of the reflective or transmissive type, analogous to a mirror or lens, respectively. A grating has a mode, in which there is no diffraction. An idealised grating is considered here which is made up of a set of slits of spacing d, assuming a plane wave of monochromatic light of wavelength λ with normal incidence, each slit in the grating acts as a quasi point-source from which light propagates in all directions. After light interacts with the grating, the light is composed of the sum of interfering wave components emanating from each slit in the grating. At any given point in space through which diffracted light may pass, similarly, when the path difference is λ, the phases will add together and maxima will occur. Thus, when light is incident on the grating, the diffracted light will have maxima at angles θm given by. It is straightforward to show if a plane wave is incident at any arbitrary angle θi. When solved for the diffracted angle maxima, the equation is, please note that these equations assume that both sides of the grating are in contact with the same medium. The light that corresponds to direct transmission is called the zero order, the other maxima occur at angles which are represented by non-zero integers m
Diffraction grating
–
A very large reflecting diffraction grating
Diffraction grating
–
An incandescent light-bulb viewed through a transmissive diffraction grating. [
dubious –
discuss]
Diffraction grating
–
A diffraction grating reflecting only the green portion of the spectrum from a room's fluorescent lighting
Diffraction grating
–
A helical fluorescent lamp photographed in a reflection diffraction-grating, showing the various spectral lines produced by the lamp.
11.
Lacquer
–
The term lacquer is used for a number of hard and potentially shiny finishes applied to materials such as wood. These fall into a number of different groups. This dries to a hard and smooth surface layer which is durable, waterproof. Asian lacquer is sometimes painted with pictures, inlaid with shell and other materials, or carved, as well as dusted with gold and given other further decorative treatments. In modern techniques, lacquer means a range of clear or coloured wood finishes that dry by solvent evaporation or a process that produces a hard. The finish can be of any level from ultra matte to high gloss. It is also used for paint, which is a paint that typically dries better on a hard. Lacquer is more durable than shellac and these ultimately derive from Sanskrit lākshā, which was used for both the Lac insect and the scarlet resinous secretion it produces that was used as wood finish. Lac resin was once imported in quantity into Europe from India along with Eastern woods. Lacquer sheen is a measurement of the shine for a given lacquer, different manufacturers have their own names and standards for their sheen. The most common names from least shiny to most shiny are, flat, matte, egg shell, satin, semi-gloss, urushiol-based lacquers differ from most others, being slow-drying, and set by oxidation and polymerization, rather than by evaporation alone. In order for it to set properly it requires a humid, the phenols oxidize and polymerize under the action of an enzyme laccase, yielding a substrate that, upon proper evaporation of its water content, is hard. These lacquers produce very hard, durable finishes that are beautiful and very resistant to damage by water, acid, alkali or abrasion. The active ingredient of the resin is urushiol, a mixture of various phenols suspended in water, the resin is derived from a tree indigenous to China, species Toxicodendron vernicifluum, commonly known as the Lacquer Tree. The fresh resin from the T. vernicifluum trees causes urushiol-induced contact dermatitis, the Chinese treated the allergic reaction with crushed shellfish, which supposedly prevents lacquer from drying properly. Lacquer skills became very highly developed in Asia, and many highly decorated pieces were produced, the earliest extant lacquer object, a red wooden bowl, was unearthed at a Hemudu culture site in China. By the Han Dynasty, many centres of production became firmly established. The knowledge of the Chinese methods of the process spread from China during the Han, Tang and Song dynasties, eventually it was introduced to Korea, Japan, Southeast
Lacquer
–
Lacquer box with inlaid
mother of pearl peony decor,
Ming Dynasty, 16th century
Lacquer
–
Armorial screen
Lacquer
–
A Chinese six-pointed tray, red lacquer over wood, from the Song Dynasty (960–1279), 12th-13th century, Metropolitan Museum of Art.
Lacquer
–
Ming Dynasty Chinese
lacquerware container, dated 16th century.
12.
Floppy disk
–
Floppy disks are read and written by a floppy disk drive. Floppy disks, initially as 8-inch media and later in 5¼-inch and 3½-inch sizes, were a form of data storage and exchange from the mid-1970s into the mid-2000s. These formats are usually handled by older equipment and these disks and associated drives were produced and improved upon by IBM and other companies such as Memorex, Shugart Associates, and Burroughs Corporation. The term floppy disk appeared in print as early as 1970, in 1976, Shugart Associates introduced the first 5¼-inch FDD. By 1978 there were more than 10 manufacturers producing such FDDs, there were competing floppy disk formats, with hard- and soft-sector versions and encoding schemes such as FM, MFM and GCR. The 5¼-inch format displaced the 8-inch one for most applications, the most common capacity of the 5¼-inch format in DOS-based PCs was 360 kB and in 1984 IBM introduced the 1.2 MB dual-sided floppy disk along with its PC-AT model. IBM started using the 720 kB double-density 3½-inch microfloppy disk on its Convertible laptop computer in 1986 and these disk drives could be added to older PC models. In 1988 IBM introduced a drive for 2.88 MB DSED diskettes in its top-of-the-line PS/2 models, throughout the early 1980s, limitations of the 5¼-inch format became clear. Originally designed to be practical than the 8-inch format, it was itself too large, as the quality of recording media grew. A number of solutions were developed, with drives at 2-, 2½-, 3-, 3½-, the large market share of the 5¼-inch format made it difficult for these new formats to gain significant market share. A variant on the Sony design, introduced in 1982 by a number of manufacturers, was then rapidly adopted. By the end of the 1980s, 5¼-inch disks had been superseded by 3½-inch disks, by the mid-1990s, 5¼-inch drives had virtually disappeared, as the 3½-inch disk became the predominant floppy disk. Floppy disks became ubiquitous during the 1980s and 1990s in their use with computers to distribute software, transfer data. Before hard disks became affordable to the population, floppy disks were often used to store a computers operating system. Most home computers from that period have a primary OS and BASIC stored as ROM, by the early 1990s, the increasing software size meant large packages like Windows or Adobe Photoshop required a dozen disks or more. In 1996, there were a five billion standard floppy disks in use. Then, distribution of packages was gradually replaced by CD-ROMs, DVDs. External USB-based floppy disk drives are available, many modern systems provide firmware support for booting from such drives
Floppy disk
–
8-inch, 5¼-inch, and 3½-inch floppy disks
Floppy disk
–
8-inch, 5¼-inch (full height), and 3½-inch drives
Floppy disk
–
A 3½-inch diskette's "floppy" magnetic material, removed from its housing
Floppy disk
–
8-inch disk drive with diskette (3½-inch disk for comparison)
13.
Blu-ray Disc
–
Blu-ray or Blu-ray Disc is a digital optical disc data storage format. It was designed to supersede the DVD format, in that it is capable of storing high-definition, the plastic disc is 120 mm in diameter and 1.2 mm thick, the same size as DVDs and CDs. Conventional Blu-ray Disc discs contain 25 GB per layer, with dual layer discs being the standard for feature-length video discs. Triple-layer discs and quadruple layers are available for BD-XL re-writer drives, the name Blu-ray refers to the blue laser used to read the disc, which allows information to be stored at a greater density than is possible with the longer-wavelength red laser used for DVDs. The main application of Blu-ray is as a medium for video material such as films and physical distribution of video games for the PlayStation 3, PlayStation 4. Besides the hardware specifications, Blu-ray is associated with a set of multimedia formats, high-definition video may be stored on Blu-ray discs with up to 2160p resolution, at up to 60 frames per second. DVD discs had been limited to a resolution of 480p or 576p. The BD format was developed by the Blu-ray Disc Association, a group representing makers of consumer electronics, computer hardware, Sony unveiled the first Blu-ray disc prototypes in October 2000, and the first prototype player was released in April 2003 in Japan. Afterwards, it continued to be developed until its release in June 2006. During the high definition disc format war, Blu-ray Disc competed with the HD DVD format. Toshiba, the company that supported HD DVD, conceded in February 2008. According to Media Research, high-definition software sales in the US were slower in the first two years than DVD software sales, Blu-ray faces competition from video on demand and the continued sale of DVDs. As of January 2016, 44% of U. S. broadband households had a Blu-ray player, the information density of the DVD format was limited by the wavelength of the laser diodes used. Following protracted development, blue laser diodes operating at 405 nanometers became available on a production basis, Sony started two projects in collaboration with Philips applying the new diodes, UDO, and DVR Blue, a format of rewritable discs that would eventually become Blu-ray Disc. The core technologies of the formats are similar, the first DVR Blue prototypes were unveiled at the CEATEC exhibition in October 2000 by Sony. A trademark for the Blue Disc logo was filed February 9,2001, on February 19,2002, the project was officially announced as Blu-ray Disc, and Blu-ray Disc Founders was founded by the nine initial members. The first consumer device arrived in stores on April 10,2003, the Sony BDZ-S77, but there was no standard for prerecorded video, and no movies were released for this player. On October 4,2004, the name Blu-ray Disc Founders was officially changed to the Blu-ray Disc Association, the Blu-ray Disc physical specifications were completed in 2004
Blu-ray Disc
–
A blank rewritable Blu-ray Disc (
BD-RE).
Blu-ray Disc
–
Blu-ray Disc
Blu-ray Disc
–
100 GB BDXL Triple layer disc made by
Sharp
Blu-ray Disc
–
Ultra HD Blu-ray
14.
CD-ROM
–
A CD-ROM /ˌsiːˌdiːˈrɒm/ is a pre-pressed optical compact disc which contains data. The name is an acronym which stands for Compact Disc Read-Only Memory, computers can read CD-ROMs, but cannot write to CD-ROMs which are not writable or erasable. From the mid-1990s until the mid-2000s, CD-ROMs were popularly used to distribute software for computers, some CDs, called enhanced CDs, hold both computer data and audio with the latter capable of being played on a CD player, while data is only usable on a computer. An early CD-ROM format was developed by Sony and Denon, introduced at a Japanese computer show in 1984 and it was an extension of Compact Disc Digital Audio, and adapted the format to hold any form of digital data, with a capacity of 540 MiB. The Yellow Book is the standard that defines the format of CD-ROMs. One of a set of books that contain the technical specifications for all CD formats. CD-ROMs are identical in appearance to audio CDs, and data are stored and retrieved in a similar manner. Discs are made from a 1.2 mm thick disc of polycarbonate plastic, data is stored on the disc as a series of microscopic indentations. A laser is shone onto the surface of the disc to read the pattern of pits. This pattern of changing intensity of the beam is converted into binary data. Several formats are used for data stored on discs, known as the Rainbow Books. The Yellow Book, published in 1988, defines the specifications for CD-ROMs, the CD-ROM standard builds on top of the original Red Book CD-DA standard for CD audio. Other standards, such as the White Book for Video CDs, the Yellow Book itself is not freely available, but the standards with the corresponding content can be downloaded for free from ISO or ECMA. There are several standards that define how to structure data files on a CD-ROM, ISO9660 defines the standard file system for a CD-ROM. ISO13490 is an improvement on this standard which adds support for non-sequential write-once and re-writeable discs such as CD-R and CD-RW, as well as multiple sessions. The ISO13346 standard was designed to address most of the shortcomings of ISO9660, and a subset of it evolved into the UDF format, which was adopted for DVDs. The bootable CD specification was issued in January 1995, to make a CD emulate a hard disk or floppy disk, is called El Torito, data stored on CD-ROMs follows the standard CD data encoding techniques described in the Red Book specification. This includes cross-interleaved Reed–Solomon coding, eight-to-fourteen modulation, and the use of pits, the structures used to group data on a CD-ROM are also derived from the Red Book
CD-ROM
–
A computer drive capable of reading CD-ROM discs
CD-ROM
–
A CD-ROM can easily store the entirety of a paper encyclopedia's words and images, plus audio & video clips
CD-ROM
–
A view of a CD-ROM drive's disassembled laser system
CD-ROM
–
The laser system of a CD-ROM drive
15.
CD-R
–
CD-R is a digital optical disc storage format. A CD-R disc is a disc that can be written once. CD-R disks are readable by most plain CD readers, i. e. CD readers manufactured prior to the introduction of CD-R and this is an advantage over CD-RW, which can be re-written but cannot be played on many plain CD readers. The CD-R, originally named CD Write-Once, specification was first published in 1988 by Philips, the Orange Book consists of several parts, furnishing details of the CD-WO, CD-MO, and CD-RW. The latest editions have abandoned the use of the term CD-WO in favor of CD-R, written CD-Rs and CD-RWs are, in the aspect of low-level encoding and data format, fully compatible with the audio CD and data CD standards. This means they use Eight-to-Fourteen Modulation, CIRC error correction, and, for CD-ROM, properly written CD-R discs on blanks of less than 80 minutes length are fully compatible with the audio CD and CD-ROM standards in all details including physical specifications. 80 minute CD-R discs marginally violate the Red Book physical format specifications, CD-RW discs have lower reflectivity than CD-R or pressed CDs and for this reason cannot meet the Red Book standard. Some hardware compatible with Red Book CDs may have difficulty reading CD-Rs and, because of their lower reflectivity, especially CD-RWs. To the extent that CD hardware can read extended-length discs or CD-RW discs, it is because that hardware has capability beyond the minimum required by the Red Book and Yellow Book standards. The dye materials developed by Taiyo Yuden made it possible for CD-R discs to be compatible with Audio CD, a standard CD-R is a 1.2 mm thick disc made of polycarbonate about 120 mm or 80 mm diameter. The 120 mm disc has a capacity of 74 minutes of audio or 650 Megabytes of data. Despite the foregoing, most CD-Rs on the market have an 80-minute capacity, there are also 90 minute/790 MiB and 99 minute/870 MiB discs, although they are less common. Also, due to the limitations of the structures in the ATIP,90 and 99 minute blanks will identify as 80 minute ones. Therefore, in order to use the capacity, these discs have to be burned using overburn options in the CD recording software. Nothing in the Red, Yellow or Orange Book standards prohibits disc reading/writing devices from having the capacity to read or write discs beyond the Compact Disc standards, the polycarbonate disc contains a spiral groove, called the pregroove, to guide the laser beam upon writing and reading information. The polycarbonate disc is coated on the side with a very thin layer of organic dye. Then, on top of the dye is coated a thin, reflecting layer of silver, finally, a protective coating of a photo-polymerizable lacquer is applied on top of the metal reflector and cured with UV-light. A blank CD-R is not empty, the pregroove has a wobble, maintaining a constant rate is essential to ensure proper size and spacing of the pits and lands burned into the dye layer
CD-R
–
Assorted CD-Rs
CD-R
–
Compact Disc Recordable (CD-R) logo/trademark
CD-R
–
Photomicrograph of the groove in a CD-R disc
CD-R
–
An example of a CD-R burned in 2000 showing dye degradation in 2008. Part of the data on it has been lost.
16.
CD-RW
–
CD-RW is a digital optical disc storage format. A CD-RW disc is a disc that can be written, read arbitrarily many times, erased. The technology was introduced in 1997, CD-RW discs require readers that have more sensitive laser optics than are required to read plain CDs. Consequently, CD-RWs cannot be read in many CD readers built prior to the introduction of CD-RW, CD-ROM drives that bear a MultiRead certification claim compatibility. CD-RW discs need to be blanked before reuse, fast blanking is much quicker, and is usually sufficient to allow rewriting the disc. Full blanking removes traces of the data, often for confidentiality reasons. It may be possible to data from full-blanked CD-RWs with specialty data recovery equipment, however. Their ideal usage field is in the creation of test discs, temporary short or mid-term backups, and in general, the CD-MO standard also allowed for an optional non-erasable zone on the disc, which could be read by normal CD-ROM reader units. Reading of the discs relied on the Kerr effect, the format was never released commercially, mostly because of its inherent incompatibility with standard CD reading units. A similar situation was present for early CD-R media, which suffered from either physical or logical incompatibilities. There were however some magneto-optical drives and media with the form factor that dont have this limitation. Unlike modern CD-RWs, CD-MO allowed for hybrid discs containing both an unmodifiable, pressed section, readable in standard drives, and a writable MO section, other kinds of magneto-optical media, unbound by the limitations of the typical CD-ROM filesystems, took the place intended for CD-MO. Rewritable media can, with hardware, according to some manufacturers. The CD-RW technology is based on phase change technology, so the degree of reflection reached is only 15–25%, the properties of the medium and the write and erase procedure is defined in the Orange Book Part III. To keep rotational speed precise, tracks have a slight superimposed sinusoidal excursion of 0.3 µm at a frequency of 22.05 kHz, in addition a 1 kHz frequency modulation is applied to provide the recorder with an absolute time reference. The grooves have a width of 0.6 µm and pitch of 1.6 µm, the media for CD-RW has basically the same layers as CD-R media. The reflective layer is, however, an alloy, which has in its original state. When writing the laser beam uses its power to heat the material to 500–700 °C
CD-RW
–
Compact Disc ReWritable (CD-RW) logo/trademark
17.
Alloy
–
An alloy is a mixture of metals or a mixture of a metal and another element. Alloys are defined by a metallic bonding character, an alloy may be a solid solution of metal elements or a mixture of metallic phases. Intermetallic compounds are alloys with a stoichiometry and crystal structure. Zintl phases are sometimes considered alloys depending on bond types. Alloys are used in a variety of applications. In some cases, a combination of metals may reduce the overall cost of the material while preserving important properties, in other cases, the combination of metals imparts synergistic properties to the constituent metal elements such as corrosion resistance or mechanical strength. Examples of alloys are steel, solder, brass, pewter, duralumin, bronze, the alloy constituents are usually measured by mass. Alloys are usually classified as substitutional or interstitial alloys, depending on the arrangement that forms the alloy. They can be classified as homogeneous, or heterogeneous or intermetallic. An alloy is a mixture of elements, which forms an impure substance that retains the characteristics of a metal. Alloys are made by mixing two or more elements, at least one of which is a metal and this is usually called the primary metal or the base metal, and the name of this metal may also be the name of the alloy. The other constituents may or may not be metals but, when mixed with the base, they will be soluble. The mechanical properties of alloys will often be different from those of its individual constituents. A metal that is very soft, such as aluminium, can be altered by alloying it with another soft metal. Although both metals are soft and ductile, the resulting aluminium alloy will have much greater strength. Adding a small amount of carbon to iron trades its great ductility for the greater strength of an alloy called steel. Due to its strength, but still substantial toughness, and its ability to be greatly altered by heat treatment, steel is one of the most useful. By adding chromium to steel, its resistance to corrosion can be enhanced, creating stainless steel, while adding silicon will alter its electrical characteristics, producing silicon steel
Alloy
–
Liquid
bronze, being poured into molds during casting.
Alloy
–
Wire rope made from
steel, which is a metal alloy whose major component is
iron, with
carbon content between 0.02% and 2.14% by mass.
Alloy
–
A
brass lamp.
Alloy
–
A gate valve, made from
Inconel.
18.
Phase change material
–
A phase change material is a substance with a high heat of fusion which, melting and solidifying at a certain temperature, is capable of storing and releasing large amounts of energy. Heat is absorbed or released when the changes from solid to liquid and vice versa, thus. Latent heat storage can be achieved through liquid–>solid, solid–>liquid, solid–>gas and liquid–>gas phase changes, however, only solid–>liquid and liquid–>solid phase changes are practical for PCMs. Solid–solid phase changes are very slow and have a relatively low heat of transformation. Initially, solid–liquid PCMs behave like sensible heat storage materials, their temperature rises as they absorb heat, unlike conventional SHS materials, however, when PCMs reach the temperature at which they change phase they absorb large amounts of heat at an almost constant temperature. The PCM continues to absorb heat without a significant rise in temperature until all the material is transformed to the liquid phase, when the ambient temperature around a liquid material falls, the PCM solidifies, releasing its stored latent heat. A large number of PCMs are available in any required temperature range from −5 up to 190 °C, within the human comfort range between 20–30 °C, some PCMs are very effective. They store 5 to 14 times more heat per unit volume than conventional materials such as water. High heat transfer rates are required during the freezing cycle Volumetric latent heat capacity can be low Flammable. The process is thus, Condensation ΔH<0, enthalpy decreases gives off heat, vaporization ΔH>0, enthalpy increases absorbs heat. Whilst this process liberates a small quantity of energy, large surfaces area allows significant heating or cooling in buildings, the corresponding materials are wool insulation, earth/clay render finishes. A specialised group of PCMs that undergo a phase transition with the associated absorption. Such materials are useful because, unlike solid/liquid PCMs, they do not require nucleation to prevent supercooling, currently, the range of solid-solid PCM solutions remains from +25°C upto +180°C Big text Thermodynamic properties. Recently also ionic liquids were investigated as novel PCMs, as most of the organic solutions are water-free, they can be exposed to air, but all salt based PCM solutions must be encapsulated to prevent water evaporation or uptake. Both types offer certain advantages and disadvantages and if they are correctly applied some of the disadvantages becomes an advantage for certain applications and they have been used since the late 19th century as a medium for the thermal storage applications. They have been used in diverse applications as refrigerated transportation for rail and road applications and their physical properties are, therefore. Unlike the ice storage system, however, the PCM systems can be used with any conventional water chiller both for a new or alternatively retrofit application. The temperature range offered by the PCM technology provides a new horizon for the services and refrigeration engineers regarding medium
Phase change material
–
A
sodium acetate heating pad. When the sodium acetate solution crystallises, it becomes warm.
Phase change material
–
Phase-change material being employed in the treatment of
neonates with
birth asphyxia
19.
Silver
–
Silver is a metallic element with symbol Ag and atomic number 47. The symbol Ag stems from Latin argentum, derived from the Greek ὰργὀς, a soft, white, lustrous transition metal, it exhibits the highest electrical conductivity, thermal conductivity, and reflectivity of any metal. The metal is found in the Earths crust in the pure, free form, as an alloy with gold and other metals. Most silver is produced as a byproduct of copper, gold, lead, Silver is more abundant than gold, but it is much less abundant as a native metal. Its purity is measured on a per mille basis, a 94%-pure alloy is described as 0.940 fine. As one of the seven metals of antiquity, silver has had a role in most human cultures. Silver has long valued as a precious metal. Silver metal is used in many premodern monetary systems in bullion coins, Silver is used in numerous applications other than currency, such as solar panels, water filtration, jewelry, ornaments, high-value tableware and utensils, and as an investment medium. Silver is used industrially in electrical contacts and conductors, in specialized mirrors, window coatings, Silver compounds are used in photographic film and X-rays. Dilute silver nitrate solutions and other compounds are used as disinfectants and microbiocides, added to bandages and wound-dressings, catheters. Silver is similar in its physical and chemical properties to its two neighbours in group 11 of the periodic table, copper and gold. This distinctive electron configuration, with an electron in the highest occupied s subshell over a filled d subshell. Silver is a soft, ductile and malleable transition metal. Silver crystallizes in a cubic lattice with bulk coordination number 12. Unlike metals with incomplete d-shells, metallic bonds in silver are lacking a covalent character and are relatively weak and this observation explains the low hardness and high ductility of single crystals of silver. Silver has a brilliant white metallic luster that can take a polish. Protected silver has greater optical reflectivity than aluminium at all wavelengths longer than ~450 nm, at wavelengths shorter than 450 nm, silvers reflectivity is inferior to that of aluminium and drops to zero near 310 nm. The electrical conductivity of silver is the greatest of all metals, greater even than copper, during World War II in the US,13540 tons of silver were used in electromagnets for enriching uranium, mainly because of the wartime shortage of copper
Silver
–
Electrolytically refined silver
Silver
–
Silver 1000
oz t (~31 kg) bullion bar
Silver
–
Cessna 210 equipped with a silver iodide generator for
cloud seeding
Silver
–
A Canadian 50 cent piece from 1951, with King George the 6th on the obverse and Canada's (now former) coat of arms on the reverse. It is made of 80% silver and 20% copper.
20.
Indium
–
Indium is a chemical element with symbol In and atomic number 49. It is a metal that makes up 0.21 parts per million of the Earths crust. Very soft and malleable, indium has a point higher than sodium and gallium. Chemically, indium is similar to gallium and thallium, and it is intermediate between the two in terms of its properties. Indium was discovered in 1863 by Ferdinand Reich and Hieronymous Theodor Richter by spectroscopic methods and they named it for the indigo blue line in its spectrum. Indium was isolated the next year, Indium is a minor component in zinc sulfide ores and is produced as a byproduct of zinc refinement. Indium has no role, though its compounds are somewhat toxic when injected into the bloodstream. Most occupational exposure is through ingestion, from which indium compounds are not absorbed well, Indium is a silvery-white, highly ductile post-transition metal with a bright luster. It is so soft that like sodium, it can be cut with a knife and it also leaves a visible line on paper. It is a member of group 13 on the periodic table, like tin, a high-pitched cry is heard when indium is bent – a crackling sound due to crystal twinning. Like gallium, indium is able to wet glass, like both, indium has a low melting point,156.60 °C, higher than its lighter homologue, gallium, but lower than its heavier homologue, thallium, and lower than tin. The density of indium,7.31 g/cm3, is greater than gallium. Below the critical temperature,3.41 K, indium becomes a superconductor, Indium displays a ductile viscoplastic response, found to be size-independent in tension and compression. However it does have an effect in bending and indentation, associated to a length-scale of order 50–100 µm. Indium has 49 electrons, with a configuration of 4d105s25p1. In compounds, indium most commonly donates the three outermost electrons to become indium, In3+, in some cases, the pair of 5s-electrons are not donated, resulting in indium, In+. The stabilization of the monovalent state is attributed to the inert pair effect, in which relativistic effects stabilize the 5s-orbital, thallium shows an even stronger effect, causing oxidation to thallium to be more probable than to thallium, whereas gallium commonly shows only the +3 oxidation state. Thus, although thallium is a strong oxidizing agent, indium is not
Indium
–
Indium, 49 In
Indium
–
Indium wetting the glass surface of a test tube
Indium
–
A magnified image of an
LCD screen showing RGB pixels. Individual transistors are seen as white dots in the bottom part.
Indium
–
Ductile indium wire
21.
Antimony
–
Antimony is a chemical element with symbol Sb and atomic number 51. A lustrous gray metalloid, it is found in nature mainly as the sulfide mineral stibnite, Antimony compounds have been known since ancient times and were powdered for use as medicine and cosmetics, often known by the Arabic name, kohl. Metallic antimony was known, but it was erroneously identified as lead upon its discovery. In the West, it was first isolated by Vannoccio Biringuccio, for some time, China has been the largest producer of antimony and its compounds, with most production coming from the Xikuangshan Mine in Hunan. The industrial methods for refining antimony are roasting and reduction with carbon or direct reduction of stibnite with iron, the largest applications for metallic antimony is an alloy with lead and tin and the lead antimony plates in lead–acid batteries. Alloys of lead and tin with antimony have improved properties for solders, bullets, Antimony compounds are prominent additives for chlorine and bromine-containing fire retardants found in many commercial and domestic products. An emerging application is the use of antimony in microelectronics, Antimony is in a pnictogen and has an electronegativity of 2.05. In accordance with periodic trends, it is more electronegative than tin or bismuth, Antimony is stable in air at room temperature, but reacts with oxygen if heated to produce antimony trioxide, Sb2O3. Antimony is resistant to attack by acids, four allotropes of antimony are known, a stable metallic form and three metastable forms. Elemental antimony is a brittle, silver-white shiny metalloid, when slowly cooled, molten antimony crystallizes in a trigonal cell, isomorphic with the gray allotrope of arsenic. A rare explosive form of antimony can be formed from the electrolysis of antimony trichloride, when scratched with a sharp implement, an exothermic reaction occurs and white fumes are given off as metallic antimony forms, when rubbed with a pestle in a mortar, a strong detonation occurs. Black antimony is formed upon cooling of antimony vapor. It has the crystal structure as red phosphorus and black arsenic, it oxidizes in air. At 100 °C, it transforms into the stable form. The yellow allotrope of antimony is the most unstable and it has only been generated by oxidation of stibine at −90 °C. Above this temperature and in ambient light, this metastable allotrope transforms into the more stable black allotrope, elemental antimony adopts a layered structure in which layers consist of fused, ruffled, six-membered rings. The nearest and next-nearest neighbors form an octahedral complex, with the three atoms in each double layer slightly closer than the three atoms in the next. This relatively close packing leads to a density of 6.697 g/cm3
Antimony
–
Antimony, 51 Sb
Antimony
–
Native antimony with
oxidation products
Antimony
–
Stibnite
Antimony
–
The Italian metallurgist Vannoccio Biringuccio described the first procedure of how to isolate antimony.
22.
Tellurium
–
Tellurium is a chemical element with symbol Te and atomic number 52. It is a brittle, mildly toxic, rare, silver-white metalloid, Tellurium is chemically related to selenium and sulfur. It is occasionally found in form as elemental crystals. Tellurium is far more common in the universe as a whole than on Earth, Tellurium was discovered in the Habsburg Empire, in 1782 by Franz-Joseph Müller von Reichenstein in a mineral containing tellurium and gold. Martin Heinrich Klaproth named the new element in 1798 after the Latin word for earth, gold telluride minerals are the most notable natural gold compounds. However, they are not a significant source of tellurium itself. Commercially, the use of tellurium is copper and steel alloys. Applications in CdTe solar panels and semiconductors also consume a portion of tellurium production. Tellurium has no function, although fungi can use it in place of sulfur. In humans, tellurium is partly metabolized into dimethyl telluride, 2Te, Tellurium has two allotropes, crystalline and amorphous. When crystalline, tellurium is silvery-white with a metallic luster and it is a brittle and easily pulverized metalloid. Amorphous tellurium is a black-brown powder prepared by precipitating it from a solution of acid or telluric acid. Tellurium is a semiconductor that shows a greater electrical conductivity in certain directions depending on atomic alignment, when molten, tellurium is corrosive to copper, iron, and stainless steel. Of the chalcogens, tellurium has the highest melting and boiling points, at 722.66 K and 1,261 K, Tellurium adopts a polymeric structure consisting of zig-zag chains of Te atoms. This gray material resists oxidation by air and is not volatile, naturally occurring tellurium has eight isotopes. Six of those isotopes, 120Te, 122Te, 123Te, 124Te, 125Te and 126Te, are stable, the other two, 128Te and 130Te, have been found to be slightly radioactive, with extremely long half-lives, including 2.2 ×1024 years for 128Te. This is the longest known half life among all radionuclides and is approximately 160 trillion times the age of the known universe, stable isotopes comprise only 33. 2% of naturally occurring tellurium. A further thirty artificial radioisotopes of tellurium are known with atomic masses ranging from 105 to 142, there are also 17 nuclear isomers, with half lives of up to 154 days
Tellurium
–
Tellurium, 52 Te
Tellurium
–
Klaproth named the new element and credited
von Reichenstein with its discovery
Tellurium
–
A sample of tellurium dioxide powder
23.
Compact Disc player
–
A CD player is an electronic device that plays audio compact discs, which are a digital optical disc data storage format. CD players were first sold to consumers in 1982, CDs typically contain recordings of audio material such as music. CD players are often a part of home systems, car audio systems. With the exception of CD boomboxes, most CD players do not produce sound by themselves, most CD players only produce an output signal via a headphone jack and/or RCA jacks. To listen to using a CD player with a headphone output jack. To use a CD player in a stereo system, the user connects an RCA cable to the RCA jacks or other outputs and connects it to a hi-fi. They are also manufactured as portable devices, which are battery powered, modern units can play other formats in addition to PCM audio coding used in CDs, such as MP3, AAC and WMA. DJs playing dance music at clubs often use specialized players with a playback speed to alter the pitch. Audio engineers using CD players to play music for an event through a reinforcement system use professional audio-grade CD players. CD playback functionality is also valuable on CD-ROM/DVD-ROM drive equipped computers as well as on DVD players, American inventor James T. Russell has been credited with inventing the first system to record digital information on an optical transparent foil that is lit from behind by a high-power halogen lamp. Russells patent application was first filed in 1966, and he was granted a patent in 1970, following litigation, Sony and Philips licensed Russells patents in the 1980s. The Compact Disc is an evolution of LaserDisc technology, where a laser beam is used that enables the high information density required for high-quality digital audio signals. Prototypes were developed by Philips and Sony independently in the late 1970s, in 1979, Sony and Philips set up a joint task force of engineers to design a new digital audio disc. After a year of experimentation and discussion, the Red Book CD-DA standard was published in 1980, after their commercial release in 1982, compact discs and their players were extremely popular. Despite costing up to $1,000, over 400,000 CD players were sold in the United States between 1983 and 1984. The success of the disc has been credited to the cooperation between Philips and Sony, who came together to agree upon and develop compatible hardware. The unified design of the disc allowed consumers to purchase any disc or player from any company. In 1974, L. However, due to the performance of the analog format
Compact Disc player
–
Sony CDP-101 from 1982, one of the earliest
CD players affordable to
consumers.
Compact Disc player
–
The Red book Digital Audio logo is present in all discs and players ensuring compatibility
Compact Disc player
–
A 1980s-era
Denon CD player
Compact Disc player
–
Philips CD100 Player
24.
Personal computer
–
A personal computer is a multi-purpose electronic computer whose size, capabilities, and price make it feasible for individual use. PCs are intended to be operated directly by a end-user, rather than by an expert or technician. In the 2010s, PCs are typically connected to the Internet, allowing access to the World Wide Web, personal computers may be connected to a local area network, either by a cable or a wireless connection. In the 2010s, a PC may be, a multi-component desktop computer, designed for use in a location a laptop computer, designed for easy portability or a tablet computer. In the 2010s, PCs run using a system, such as Microsoft Windows, Linux. The very earliest microcomputers, equipped with a front panel, required hand-loading of a program to load programs from external storage. Before long, automatic booting from permanent read-only memory became universal, in the 2010s, users have access to a wide range of commercial software, free software and free and open-source software, which are provided in ready-to-run or ready-to-compile form. Since the early 1990s, Microsoft operating systems and Intel hardware have dominated much of the computer market, first with MS-DOS. Alternatives to Microsofts Windows operating systems occupy a minority share of the industry and these include Apples OS X and free open-source Unix-like operating systems such as Linux and Berkeley Software Distribution. Advanced Micro Devices provides the alternative to Intels processors. PC is an initialism for personal computer, some PCs, including the OLPC XOs, are equipped with x86 or x64 processors but not designed to run Microsoft Windows. PC is used in contrast with Mac, an Apple Macintosh computer and this sense of the word is used in the Get a Mac advertisement campaign that ran between 2006 and 2009, as well as its rival, Im a PC campaign, that appeared in 2008. Since Apples transition to Intel processors starting 2005, all Macintosh computers are now PCs, the “brain” may one day come down to our level and help with our income-tax and book-keeping calculations. But this is speculation and there is no sign of it so far, in the history of computing there were many examples of computers designed to be used by one person, as opposed to terminals connected to mainframe computers. Using the narrow definition of operated by one person, the first personal computer was the ENIAC which became operational in 1946 and it did not meet further definitions of affordable or easy to use. An example of an early single-user computer was the LGP-30, created in 1956 by Stan Frankel and used for science and it came with a retail price of $47, 000—equivalent to about $414,000 today. Introduced at the 1965 New York Worlds Fair, the Programma 101 was a programmable calculator described in advertisements as a desktop computer. It was manufactured by the Italian company Olivetti and invented by the Italian engineer Pier Giorgio Perotto, the Soviet MIR series of computers was developed from 1965 to 1969 in a group headed by Victor Glushkov
Personal computer
–
Commodore PET in 1983 (at
American Museum of Science and Energy)
Personal computer
Personal computer
–
IBM Personal Computer XT in 1988
Personal computer
–
The 8-bit
PMD 85 personal computer produced in 1985-1990 by the
Tesla company in the former socialist
Czechoslovakia. This computer was produced locally (in
Piešťany) due to a lack of foreign currency with which to buy systems from the West.
25.
USB flash drive
–
USB flash drives are typically removable and rewritable, and physically much smaller than an optical disc. Most weigh less than 30 grams, since first appearing on the market in late 2000, as with virtually all computer memory devices, storage capacities have risen while prices have dropped. As of March 2016, flash drives with anywhere from 8 to 256 GB are frequently sold, storage capacities as large as 2 TB are planned, with steady improvements in size and price per capacity expected. Some allow up to 100,000 write/erase cycles, depending on the type of memory chip used. USB flash drives are used for the same purposes for which floppy disks or CDs were once used, i. e. for storage, data back-up. They are smaller, faster, have thousands of times more capacity, additionally, they are immune to electromagnetic interference, and are unharmed by surface scratches.44 MB3. 5-inch floppy disk. The USB connector may be protected by a cap or by retracting into the body of the drive. Most flash drives use a standard type-A USB connection allowing connection with a port on a personal computer, USB flash drives draw power from the computer via the USB connection. Some devices combine the functionality of a media player with USB flash storage. Pua Khein-Seng from Malaysia is considered by many to be the Father of Pen Drive and he is notable for incorporating the worlds first single chip USB flash controller. Pua hails from Sekinchan, Selangor, Malaysia, pua founded Phison Electronics based in Taiwan with four other partners and is believed to have produced the worlds first USB flash drive with system-on-chip technology. Competing claims have made by Singaporean company Trek Technology and Chinese company Netac Technology, Both Trek Technology. Trek won a Singaporean suit, but a court in the United Kingdom revoked one of Treks UK patents, Trek Technology and IBM began selling the first USB flash drives commercially in 2000. IBMs USB flash drive became available on December 15,2000, in 2000, Lexar introduced a Compact Flash card with a USB connection, and a companion card read/writer and USB cable that eliminated the need for a USB hub. That is considerably slower than what a hard drive or solid-state drive can achieve when connected via the SATA interface. Transfer rates may be given in megabytes per second, megabits per second, or in optical drive multipliers such as 180X.1, which is limited to 12 Mbit/s with accounted overhead. The effective transfer rate of a device is significantly affected by the access pattern, for example. Like USB2.0 before it, USB3.0 dramatically improved data rates compared to its predecessor
USB flash drive
–
An original IBM DiskOnKey USB flash drive, providing 8 MB of storage
USB flash drive
–
SanDisk Cruzer Micro, a brand of USB flash drives
USB flash drive
–
Internals of a typical USB flash drive
USB flash drive
–
A
Kingston card reader which accepts
Micro SD memory cards (
Transcend card shown partially inserted), and acts as a USB flash drive; resulting size is approximately 2 cm in length, 1 cm in width, and 2 mm in thickness.
26.
Alexander Graham Bell
–
Alexander Graham Bell was a Scottish-born scientist, inventor, engineer, and innovator who is credited with patenting the first practical telephone. Bells father, grandfather, and brother had all been associated with work on elocution and speech and his research on hearing and speech further led him to experiment with hearing devices which eventually culminated in Bell being awarded the first U. S. patent for the telephone in 1876. Bell considered his most famous invention an intrusion on his work as a scientist. Many other inventions marked Bells later life, including groundbreaking work in optical telecommunications, hydrofoils, and aeronautics. Although Bell was not one of the 33 founders of the National Geographic Society, he had a influence on the magazine while serving as the second president from January 7,1898. Alexander Bell was born in Edinburgh, Scotland, on March 3,1847, the family home was at 16 South Charlotte Street, and has a stone inscription marking it as Alexander Graham Bells birthplace. He had two brothers, Melville James Bell and Edward Charles Bell, both of whom would die of tuberculosis and his father was Professor Alexander Melville Bell, a phonetician, and his mother was Eliza Grace. Born as just Alexander Bell, at age 10, he made a plea to his father to have a name like his two brothers. To close relatives and friends he remained Aleck, as a child, young Bell displayed a natural curiosity about his world, resulting in gathering botanical specimens as well as experimenting even at an early age. His best friend was Ben Herdman, a neighbour whose family operated a flour mill, young Bell asked what needed to be done at the mill. In return, Bens father John Herdman gave both boys the run of a workshop in which to invent. From his early years, Bell showed a sensitive nature and a talent for art, poetry, with no formal training, he mastered the piano and became the familys pianist. Despite being normally quiet and introspective, he revelled in mimicry and he also developed a technique of speaking in clear, modulated tones directly into his mothers forehead wherein she would hear him with reasonable clarity. Bells preoccupation with his mothers deafness led him to study acoustics and his family was long associated with the teaching of elocution, his grandfather, Alexander Bell, in London, his uncle in Dublin, and his father, in Edinburgh, were all elocutionists. His father published a variety of works on the subject, several of which are well known, especially his The Standard Elocutionist. The Standard Elocutionist appeared in 168 British editions and sold over a quarter of a million copies in the United States alone, in this treatise, his father explains his methods of how to instruct deaf-mutes to articulate words and read other peoples lip movements to decipher meaning. Bells father taught him and his brothers not only to write Visible Speech but to any symbol. Bell became so proficient that he became a part of his fathers public demonstrations, as a young child, Bell, like his brothers, received his early schooling at home from his father
Alexander Graham Bell
–
Portrait photo taken between 1914–19.
Alexander Graham Bell
–
Melville House, the Bells' first home in North America, now a
National Historic Site of Canada.
Alexander Graham Bell
–
Bell, top right, providing
pedagogical instruction to teachers at the Boston School for Deaf Mutes, 1871. Throughout his life he referred to himself as "a teacher of the deaf".
Alexander Graham Bell
–
Alexander Graham Bell's telephone patent drawing, March 7, 1876.
27.
Charles Sumner Tainter
–
Tainter was born in Watertown, Massachusetts, where he attended public school. His education was modest, acquiring his knowledge mostly through self-education, in 1878 he opened his own shop for the production of scientific instruments in Cambridgeport, Massachusetts, where he made the acquaintance of Alexander Graham Bell. A year later Bell called Tainter to what would become his Volta Laboratory in Washington, Edison subsequently sued the Volta Graphophone Company for patent infringement, but the case was settled by a compromise between the two. In 1887 Tainter invented the helically wound paper tube as an improved graphophone cylinder and this design was light and strong, and came to be widely used in applications far removed from its original intent, such as mailing tubes and product containers. In 1888 he was stricken with pneumonia, which would incapacitate him intermittently for the rest of his life, leading him and his wife to move to San Diego. After the death of his first wife in 1924, he married Laura F. Onderdonk in 1928, Tainter received several distinguished awards for his graphophone. The daily agenda books described in detail the project work Tainter conducted at the Volta Laboratory during the 1880s, patent images viewable in TIFF format U. S. Patent 235,496 Photophone Transmitter, filed September 1880, issued December 1880 U. S, patent 235,497 Selenium Cell, filed September 1880, issued December 1880 U. S. Patent 235,616 Process Of Treating Selenium To Increase Its Electric Conductivity, filed August 1880, patent 241,909 Photophonic Receiver, filed March 1881, issued May 1881 U. S. Patent 336,173 Telephone Transmitter, filed April 1885, issued February 1886 U. S, patent 341,212 Reproducing Sounds from Phonograph Records, filed November 1885, issued May 1886 U. S. Patent 341,213 Transmitting And Recording Sounds By Radiant Energy, filed November 1885, patent 341,214 Recording and Reproducing Speech and Other Sounds, filed June 1885, issued May 1886 U. S. Patent 341,288 Apparatus for Recording and Reproducing Sounds, filed December 1885, patent 374,133 Paper Cylinder for Graphophonic Records, filed April 1887, issued November 1887 U. S. Patent 375,579 Apparatus for Recording and Reproducing Speech and Other Sounds, filed July 1887, patent 380,535 Graphophone, filed December 1887, issued April 1888 U. S. Patent 421,450 Graphophone Tablet, filed November 1887, issued February 1890 U. S. C, frow, George L. & Sefl, Albert F. The Edison Cylinder Phonographs 1877 -1929, Kent, Great Britain, phonographen und Grammaphone, Braunschweig, Germany, Klinkhardt and Biermann,1979. The Illustrated History of Phonographs, translation by Douglas Tubbs, VILO Inc, collecting Phonographs and Gramaphones, Christies International Collectors Series, Mayflower Books, New York,1980. The Phonograph and How to Use It, Allen Koenigsberg, New York,1971, charles Tainter and the Graphophone Plaque in Washington D. C. marking the successful Bell/Tainter photophone experiment
Charles Sumner Tainter
–
Charles Sumner Tainter c.1886
Charles Sumner Tainter
–
Tainter in 1919
28.
David Paul Gregg
–
Dr. David Paul Gregg was the inventor of the Optical disc. Gregg was inspired to create the disc in 1958 while working at California electronics company, Westrex. His patent for a Videodisk was filed in March 1962 while working to advance electron beam recording and reproducing, Gregg went to work at 3Ms Mincom division with experienced television videotape engineers Wayne Johnson and Dean De Moss. The three men subsequently filed patents to cover a disc recording system, a way to duplicate discs, when Mincom contracted Stanfords SRI to further the research, Gregg left and formed his own company Gauss Electrophysics. In 1968 the Gregg and Gauss patents were purchased by MCA and his designs and patents paved the way for the Laserdisc, which helped with the creation of the DVD, compact discs, and MiniDisc. In 1963 he also invented a video camera which could store several minutes worth of images onto an optical video disk. There was no patent files for the camera and only little is known about it, Dr. Gregg died in Culver City, California in November 2001 at the age of 78. When Dr. Gregg had improvised his invention and he imagined himself as a consumer. Patents and inventorship issues over the last thirty years of optical storage, paper presented at the,3109 doi,10. 1117/12.280678 Another article
David Paul Gregg
29.
Royalty income
–
A royalty is a payment made by one party, the licensee or franchisee to another that owns a particular asset, the licensor or franchisor for the right to ongoing use of that asset. A royalty interest is the right to collect a stream of future royalty payments, license agreements can be regulated, particularly where a government is the resource owner, or they can be private contracts that follow a general structure. However, certain types of agreements have comparable provisions. When a government owns the resource in question, the transaction is subject to legal. In the United States, fee simple ownership of the mineral is possible by a private individual, local taxing authorities may impose a severance tax on the unrenewable natural resources extracted from within their authority. The Federal Government receives royalties on production on federal lands, managed by the Bureau of Ocean Energy Management, Regulation and Enforcement, an example from Canadas north is the federal Frontier Lands petroleum royalty regime. In this manner risks and profits are shared between the government of Canada and the petroleum developer and this attractive royalty rate is intended to encourage oil and gas exploration in the remote Canadian frontier lands where costs and risks are higher than other locations. In many jurisdictions oil and gas royalty interests are considered property under the NAICS classification code. As a standard example, for every $100 bbl of oil sold on a U. S. federal well with a 25% royalty, the U. S. government does not pay and will only collect revenues. All risk and liability lie upon the operator of the well, Royalties in the forestry industry are called stumpage. An intangible asset such as a patent gives the owner an exclusive right to prevent others from practicing the patented technology in the country issuing the patent for the term of the patent. The right may be enforced in a lawsuit for monetary damages and/or imprisonment for violation on the patent, patent rights may be divided and licensed out in various ways, on an exclusive or non-exclusive basis. The license may be subject to limitations as to time or territory, a license may encompass an entire technology or it may involve a mere component or improvement on a technology. In the United States, reasonable royalties may be imposed, both after-the-fact and prospectively, by a court as a remedy for infringement. 0%, however, the range extended from 0% to 50%. All of these agreements may not have been at arms length, in license negotiation, firms might derive royalties for the use of a patented technology from the retail price of the downstream licensed product. In the Arab countries, it may be found, that a royalty as a percentage of sales may be difficult to transact, a flat fee may be preferred as percentages may be interpreted as percentage of profit. Trade marks are words, logos, slogans, sounds, or other expressions that distinguish the source, origin. Trade marks offer the public a means of identifying and assuring themselves of the quality of the good or service and they may bring consumers a sense of security, integrity, belonging, and a variety of intangible appeals
Royalty income
.
