IRC +10216 or CW Leonis is a well-studied carbon star, embedded in a thick dust envelope. It was first discovered in 1969 by a group of astronomers led by Eric Becklin, based upon infrared observations made with the 62 inches Caltech Infrared Telescope at Mount Wilson Observatory, its energy is emitted at infrared wavelengths. At a wavelength of 5 μm, it was found to have the highest flux of any object outside the Solar System. CW Leonis is believed to be in a late stage of its life, blowing off its own sooty atmosphere to form a white dwarf in a distant future. Based upon isotope ratios of magnesium, the initial mass of this star has been constrained to lie between 3–5 solar masses; the mass of the star's core, the final mass of the star once it becomes a white dwarf, is about 0.7–0.9 solar masses. Its bolometric luminosity varies over the course of a 649-day pulsation cycle, ranging from a minimum of about 6,250 times the Sun's luminosity up to a peak of around 15,800 times; the overall output of the star is best represented by a luminosity of 11,300 L☉.
The carbon-rich gaseous envelope surrounding this star is at least 69,000 years old and the star is losing about × 10−5 solar masses per year. The extended envelope contains at least 1.4 solar masses of material. Speckle observations from 1999 show a complex structure to this dust envelope, including partial arcs and unfinished shells; this clumpiness may be caused by a magnetic cycle in the star, comparable to the solar cycle in the Sun and results in periodic increases in mass loss. Various chemical elements and about 50 molecules have been detected in the outflows from CW Leonis, among others nitrogen and water, silicon and iron. One theory was that the star was once surrounded by comets which melted once the star started expanding, but water is now thought to form in the atmospheres of all carbon stars. If the distance to this star is assumed to be at the lower end of the estimate range, 120 pc the astrosphere surrounding the star spans a radius of about 84,000 AU; the star and its surrounding envelope are advancing at a velocity of more than 91 km/s through the surrounding interstellar medium.
It is moving with a space velocity of = km s−1. Several papers have suggested. ALMA and astrometric measurements may show orbital motion; the astrometric measurements, combined with a model including the companion, provide a parallax measurement showing that CW Leonis is the closest carbon star to the Earth. List of largest stars Nibiru cataclysm Water Found Around Nearby Star CW Leonis NASA article. Variations in the dust envelope around IRC +10216 revealed by aperture masking interferometry Simbad info for IRC +10216 including over 1200 articles discussing this object. Http://jumk.de/astronomie/special-stars/cw-leonis.shtml CW Leonis on WikiSky: DSS2, SDSS, GALEX, IRAS, Hydrogen α, X-Ray, Sky Map and images
Cyaphide, P≡C−, is the phosphorus analogue of cyanide. It is not known as a discrete salt, however, In silico measurements reveal that the -1 charge in this ion is location on carbon, as opposed to phosphorus. Organometallic complexes of cyaphide were first reported in 1992. More recent preparations use two other routes: Treatment of the ɳ1-coordinated phosphaalkyne complex trans-+ with an alkoxide resulted in desilylation, followed by subsequent rearrangement to the corresponding carbon-bound cyaphide complex. Cyaphide-alkynyl complexes are prepared similarly. An actinide cyaphide complex can be prepared by C-O bond cleavage of the phosphaethynolate anion, the phosphorus analogue of cyanate. Reaction of the uranium complex with in the presence of 2.2.2-cryptand results in the formation of a dinuclear, oxo-bridged uranium complex featuring a C≡P ligand. Phosphaalkyne
Zinc phosphide is an inorganic chemical compound. It is a grey solid, although commercial samples are dark or black, it is used as a rodenticide. Zn3P2 is a semiconductor with a direct band gap of 1.5 eV and may have applications in photovoltaic cells. A second zinc phosphide is known, with the stoichiometry ZnP2. Zinc phosphide can be prepared by the reaction of zinc with phosphorus. 3 Zn + 2 P → Zn3P2Another method of preparation include reacting tri-n-octylphosphine with dimethylzinc. Zinc phosphide reacts with water to produce phosphine and zinc hydroxide: Zn3P2 + 6 H2O → 2 PH3 + 3 Zn2 Zn3P2 has a room-temperature tetragonal form that converts to a cubic form at around 845 °C. In the room-temperature form there are discrete P atoms, zinc atoms are tetrahedrally coordinated and phosphorus six coordinate, with zinc atoms at 6 of the vertices of a distorted cube. ZnP2 has two forms, a lower-temperature red tetragonal form and a black monoclinic form. In both of these there are chains of P atoms, helical in the tetragonal, semi-spiral in the monoclinic.
Zinc phosphide is an ideal candidate for thin film photovoltaic applications, for it has strong optical absorption and an ideal band gap. In addition to this, both zinc and phosphorus are found abundantly in the earth’s crust, meaning that material extraction cost is low compared with that of other thin film photovoltaics. Both zinc and phosphorus are nontoxic, not the case for other common commercial thin film photovoltaics, like cadmium telluride. Researchers at the University of Alberta were the first to synthesize colloidal zinc phosphide. Before this, researchers were able to create efficient solar cells from bulk zinc phosphide, but their fabrication required temperatures greater than 850°C or complicated vacuum deposition methods. By contrast, colloidal zinc phosphide nanoparticles, contained in a zinc phosphide “ink”, allows for inexpensive, easy large-scale production, by means of slot-die coating or spray coating; the testing and development of these zinc phosphide thin films is still in its early stages, but early results have been positive.
Prototype heterojunction devices fabricated from zinc phosphide nanoparticle ink exhibited a rectification ratio of 600 and photosensitivity with an on/off ratio near 100. These are both acceptable suitability benchmarks for solar cells. Development still needs to be made on optimizing the nanoparticle ink formation and device architecture before commercialization is possible, but commercial spray-on zinc phosphide solar cells may be possible within ten years. Metal phosphides have been used as rodenticides. A mixture of food and zinc phosphide is left; the acid in the digestive system of the rodent reacts with the phosphide to generate toxic phosphine gas. This method of vermin control has possible use in places where rodents are immune to other common poisons. Other pesticides similar to zinc phosphide are calcium phosphide. Zinc phosphide is added to rodent baits in amount of around 0.75-2%. Such baits have a strong, pungent garlic-like odor characteristic of phosphine liberated by hydrolysis.
The odor has a repulsive effect on other animals. The baits have to contain sufficient amount of zinc phosphide in sufficiently attractive food in order to kill rodents in a single serving. Rodenticide-grade zinc phosphide comes as a black powder containing 75% of zinc phosphide and 25% of antimony potassium tartrate, an emetic to cause vomiting if the material is accidentally ingested by humans or domestic animals. However, it is still effective against rats, guinea pigs and rabbits, none of which have a vomiting reflex; the New Zealand Environmental Protection Authority has approved the import and manufacture of Microencapsulated Zinc Phosphide for the ground control of possums. The application was made by Pest Tech Limited, with support from Connovation Ltd, Lincoln University and the Animal Health Board, it will be used as an additional vertebrate poison in certain situations. Unlike 1080 poison, it cannot be used for aerial application. Zinc phosphide is toxic. In Indian certification markings, it is marked as'Highly Dangerous', which means that 1–50 mg of the substance ingested orally can be lethal.
Zinc Phosphide Pesticide Information Profile - Extension Toxicology Network EPA Proposed Risk Mitigation Decision for Nine Rodenticides Zinc phosphide in the Pesticide Properties DataBase Zinc phosphide properties and use in Michigan MD0173 - Pesticides in the military
Gallium phosphide, a phosphide of gallium, is a compound semiconductor material with an indirect band gap of 2.24 eV at room temperature. The polycrystalline material has the appearance of pale grayish pieces. Undoped single crystals are orange, but doped wafers appear darker due to free-carrier absorption, it is insoluble in water. Sulfur or tellurium are used as dopants to produce n-type semiconductors. Zinc is used as a dopant for the p-type semiconductor. Gallium phosphide has applications in optical systems, its refractive index is between 4.30 at 262 nm, 3.45 at 550 nm and 3.19 at 840 nm, higher than in most known materials, including diamond. Gallium phosphide has been used in the manufacture of low-cost red and green light-emitting diodes with low to medium brightness since the 1960s, it has a short life at higher current and its lifetime is sensitive to temperature. It is used standalone or together with gallium arsenide phosphide. Pure GaP LEDs emit green light at a wavelength of 555 nm.
Nitrogen-doped GaP emits yellow-green light, zinc oxide doped. Gallium phosphide is transparent for yellow and red light, therefore GaAsP-on-GaP LEDs are more efficient than GaAsP-on-GaAs. At temperatures above ~900 °C, gallium phosphide dissociates and the phosphorus escapes as a gas. In crystal growth from a 1500 °C melt, this must be prevented by holding the phosphorus in with a blanket of molten boric oxide in inert gas pressure of 10-100 atmospheres; the process is called liquid encapsulated Czochralski growth, an elaboration of the Czochralski process used for silicon wafers. Haynes, William M. ed.. CRC Handbook of Chemistry and Physics. CRC Press. ISBN 1439855110. Ioffe NSM data archive
Indium phosphide is a binary semiconductor composed of indium and phosphorus. It has a face-centered cubic crystal structure, identical to that of GaAs and most of the III-V semiconductors. Indium phosphide can be prepared from the reaction of white phosphorus and indium iodide at 400 °C. by direct combination of the purified elements at high temperature and pressure, or by thermal decomposition of a mixture of a trialkyl indium compound and phosphine. InP is used in high-power and high-frequency electronics because of its superior electron velocity with respect to the more common semiconductors silicon and gallium arsenide, it was used with indium gallium arsenide to make a record breaking pseudomorphic heterojunction bipolar transistor that could operate at 604 GHz. It has a direct bandgap, making it useful for optoelectronics devices like laser diodes; the company Infinera uses indium phosphide as its major technological material for manufacturing photonic integrated circuits for the optical telecommunications industry, to enable wavelength-division multiplexing applications.
InP is used as a substrate for epitaxial indium gallium arsenide based opto-electronic devices. The application fields of InP splits up into three main areas, it is used as the basis - for optoelectronic components - for high-speed electronics. - for photovoltaics There is still a vastly under-utilized, yet technically exciting zone in the electromagnetic spectrum between microwaves and infrared referred to as “Terahertz”. Electromagnetic waves in this range possess hybrid properties they show high-frequency- and optical characteristics simultaneously. InP based. InP based lasers and LEDs can emit light in the broad range of 1200 nm up to 12 µm; this light is used for fibre based Telecom and Datacom applications in all areas of the digitalised world. Light is used for sensing applications. On one hand there are spectroscopic applications, where a certain wavelength is needed to interact with matter to detect diluted gases for example. Optoelectronic terahertz is used in ultra-sensitive spectroscopic analysers, thickness measurements of polymers and for the detection of multilayer coatings in the automotive industry.
On the other hand there is a huge benefit of specific InP lasers. The radiation can not harm the retina. InP lasers in LiDAR will be a key component for the mobility of the future and the automation industry. Indium Phosphide is used to produce efficient lasers, sensitive photodetectors and modulators in the wavelength window used for telecommunications, i.e. 1550 nm wavelengths, as it is a direct bandgap III-V compound semiconductor material. The wavelength between about 1510 nm and 1600 nm has the lowest attenuation available on optical fibre. InP is a used material for the generation of laser signals and the detection and conversion of those signals back to electronic form. Wafer diameters range from 2-4 inches. Applications are: • Long-haul optical fibre connections over great distance up to 5000 km >10 Tbit/s • Metro ring access networks • Company networks and data center • Fibre to the home • Connections to wireless 3G, LTE and 5G base stations • Free space satellite communication Spectroscopic Sensing aiming environmental protection and identification of dangerous substances • A growing field is sensing based on the wavelength regime of InP.
One example for Gas Spectroscopy is drive test equipment with real-time measurement of. • Another example is FT-IR-Spectrometer VERTEX with a terahertz source. The terahertz radiation is generated from the beating signal of 2 InP lasers and an InP antenna that transforms the optical signal to the terahertz regime. • Stand-Off detection of traces of explosive substances on surfaces, e.g. for safety applications on airports or crime scene investigation after assassination attempts. • Quick verification of traces of toxic substances in gases and liquids or surface contaminations down to the ppb level. • Spectroscopy for non-destructive product control of e.g. food • Spectroscopy for many novel applications in air pollution control are being discussed today and implementations are on the way. Discussed in the LiDAR arena is the wavelength of the signal. While some players have opted for 830-to-940-nm wavelengths to take advantage of available optical components, companies are turning to longer wavelengths in the also-well-served 1550-nm wavelength band, as those wavelengths allow laser powers 100 times higher to be employed without compromising public safety.
Lasers with emission wavelengths longer than ≈ 1.4 μm are called “eye-safe” because light in that wavelength range is absorbed in the eye's cornea and vitreous body and therefore cannot damage the sensitive retina). • LiDAR-based sensor technology can provide a high level of object identification and classification with three-dimensional imaging techniques. • The automotive industry will adopt a chip-based, low cost solid state LiDAR sensor technology instead of large, mechanical LiDAR systems in the future. • For the most advanced chip-based LiDAR systems, InP will play an important role and will enable autonomous driving.. The longer eye safe wavelength is more appropriate dealing with real world conditions like dust and rain. Today´s semiconduc
Copper phosphide, Cu3P copper phosphide, cuprous phosphide and phosphor copper, is a compound of copper and phosphorus, a phosphide of copper. It has the appearance of yellowish-grey brittle mass of crystalline structure, it does not react with water. Copper phosphide has a role in copper alloys, namely in phosphor bronze, it is a good deoxidizer of copper. Copper phosphide can be produced in a reverberatory furnace or in a crucible, e.g. by a reaction of red phosphorus with a copper-rich material. It can be prepared photochemically, by irradiating cupric hypophosphite with ultraviolet radiation; when subjected to ultraviolet light, copper phosphide shows fluorescence. A blue-black film of copper phosphide forms on white phosphorus when subjected to a solution of copper salt; the particles can be removed, helped by their fluorescence. Formation of protective layer of copper phosphide is used in cases of phosphorus ingestion, when gastric lavage with copper sulfate is employed as part of the cure