Nicotine is a naturally produced alkaloid in the nightshade family of plants (most predominantly in tobacco and Duboisia hopwoodii)[6] and is widely used recreationally as a stimulant and anxiolytic. As a pharmaceutical drug, it is used for smoking cessation to relieve withdrawal symptoms.[7][4][8][9] Nicotine acts as a receptor agonist at most nicotinic acetylcholine receptors (nAChRs),[10][11][12] except at two nicotinic receptor subunits (nAChRα9 and nAChRα10) where it acts as a receptor antagonist.[10]
https://en.wikipedia.org/wiki/Nicotine
Caffeine is a central nervous system (CNS) stimulant of the methylxanthine class.[11] There are several known mechanisms of action to explain the effects of caffeine. The most prominent is that it reversibly blocks the action of adenosine on its receptors and consequently prevents the onset of drowsiness induced by adenosine. Caffeine also stimulates certain portions of the autonomic nervous system.
Caffeine can have both positive and negative health effects. It can treat and prevent the premature infant breathing disorders bronchopulmonary dysplasia of prematurity and apnea of prematurity. Caffeine citrate is on the WHO Model List of Essential Medicines.[17]
https://en.wikipedia.org/wiki/Caffeine
Deoxyadenosine monophosphate (dAMP), also known as deoxyadenylic acid or deoxyadenylate in its conjugate acid and conjugate base forms, respectively, is a derivative of the common nucleic acid AMP, or adenosine monophosphate, in which the -OH (hydroxyl) group on the 2' carbon on the nucleotide's pentose has been reduced to just a hydrogen atom (hence the "deoxy-" part of the name). Deoxyadenosine monophosphate is abbreviated dAMP. It is a monomer used in DNA.
https://en.wikipedia.org/wiki/Deoxyadenosine_monophosphate
Cyclic adenosine monophosphate (cAMP, cyclic AMP, or 3',5'-cyclic adenosine monophosphate) is a second messenger important in many biological processes. cAMP is a derivative of adenosine triphosphate (ATP) and used for intracellular signal transduction in many different organisms, conveying the cAMP-dependent pathway. It should not be confused with 5'-AMP-activated protein kinase (AMP-activated protein kinase).
https://en.wikipedia.org/wiki/Cyclic_adenosine_monophosphate
Adenosine triphosphate (ATP) is an organic compound and hydrotrope that provides energy to drive many processes in living cells, such as muscle contraction, nerve impulse propagation, condensate dissolution, and chemical synthesis. Found in all known forms of life, ATP is often referred to as the "molecular unit of currency" of intracellular energy transfer.[2] When consumed in metabolic processes, it converts either to adenosine diphosphate (ADP) or to adenosine monophosphate (AMP). Other processes regenerate ATP so that the human body recycles its own body weight equivalent in ATP each day.[3] It is also a precursor to DNA and RNA, and is used as a coenzyme.
From the perspective of biochemistry, ATP is classified as a nucleoside triphosphate, which indicates that it consists of three components: a nitrogenous base (adenine), the sugar ribose, and the triphosphate.
https://en.wikipedia.org/wiki/Adenosine_triphosphate
Phosphorus is a chemical element with the symbol P and atomic number 15. Elemental phosphorus exists in two major forms, white phosphorus and red phosphorus, but because it is highly reactive, phosphorus is never found as a free element on Earth. It has a concentration in the Earth's crust of about one gram per kilogram (compare copper at about 0.06 grams). In minerals, phosphorus generally occurs as phosphate.
https://en.wikipedia.org/wiki/Phosphorus
Phosphorous acid (or phosphonic acid (singular)) is the compound described by the formula H3PO3. This acid is diprotic (readily ionizes two protons), not triprotic as might be suggested by this formula. Phosphorous acid is an intermediate in the preparation of other phosphorus compounds. Organic derivatives of phosphorous acid, compounds with the formula RPO3H2, are called phosphonic acids.
https://en.wikipedia.org/wiki/Phosphorous_acid
An acid anhydride is a type of chemical compound derived by the removal of water molecules from an acid.
In organic chemistry, organic acid anhydrides contain the functional group R(CO)O(CO)R'. Organic acid anhydrides often form when one equivalent of water is removed from two equivalents of an organic acid in a dehydration reaction.
In inorganic chemistry, an acid anhydride refers to an acidic oxide, an oxide that reacts with water to form an oxyacid (an inorganic acid that contains oxygen or carbonic acid), or with a base to form a salt.
https://en.wikipedia.org/wiki/Acid_anhydride
In process engineering Dry process may refer to:
- Dry process (cement) used in cement manufacture using Cement kilns
- Dry spinning process in fibre spinning
- Dry process in Coffee production
- Dry process in Coconut oil production
- Dry process in the manufacture of Separators for electrochemical cells
- BaMgAl10O17:Eu2+ (BAM), a plasma-display phosphor, undergoes oxidation of the dopant during baking. Three mechanisms are involved; absorption of oxygen atoms into oxygen vacancies on the crystal surface, diffusion of Eu(II) along the conductive layer, and electron transfer from Eu(II) to absorbed oxygen atoms, leading to formation of Eu(III) with corresponding loss of emissivity.[8] Thin coating of aluminium phosphate or lanthanum(III) phosphate is effective in creating a barrier layer blocking access of oxygen to the BAM phosphor, for the cost of reduction of phosphor efficiency.[9] Addition of hydrogen, acting as a reducing agent, to argon in the plasma displays significantly extends the lifetime of BAM:Eu2+ phosphor, by reducing the Eu(III) atoms back to Eu(II).[10]
- Y2O3:Eu phosphors under electron bombardment in presence of oxygen form a non-phosphorescent layer on the surface, where electron–hole pairs recombine nonradiatively via surface states.[11]
- ZnS:Mn, used in AC thin-film electroluminescent (ACTFEL) devices degrades mainly due to formation of deep-level traps, by reaction of water molecules with the dopant; the traps act as centers for nonradiative recombination. The traps also damage the crystal lattice. Phosphor aging leads to decreased brightness and elevated threshold voltage.[12]
- ZnS-based phosphors in CRTs and FEDs degrade by surface excitation, coulombic damage, build-up of electric charge, and thermal quenching. Electron-stimulated reactions of the surface are directly correlated to loss of brightness. The electrons dissociate impurities in the environment, the reactive oxygen species then attack the surface and form carbon monoxide and carbon dioxide with traces of carbon, and nonradiative zinc oxide and zinc sulfate on the surface; the reactive hydrogen removes sulfur from the surface as hydrogen sulfide, forming nonradiative layer of metallic zinc. Sulfur can be also removed as sulfur oxides.[13]
- ZnS and CdS phosphors degrade by reduction of the metal ions by captured electrons. The M2+ ions are reduced to M+; two M+ then exchange an electron and become one M2+ and one neutral M atom. The reduced metal can be observed as a visible darkening of the phosphor layer. The darkening (and the brightness loss) is proportional to the phosphor's exposure to electrons and can be observed on some CRT screens that displayed the same image (e.g. a terminal login screen) for prolonged periods.[14]
A strobe light or stroboscopic lamp, commonly called a strobe, is a device used to produce regular flashes of light. It is one of a number of devices that can be used as a stroboscope. The word originated from the Ancient Greek στρόβος (stróbos), meaning "act of whirling".
A typical commercial strobe light has a flash energy in the region of 10 to 150 joules, and discharge times as short as a few milliseconds, often resulting in a flash power of several kilowatts. Larger strobe lights can be used in “continuous” mode, producing extremely intense illumination.
The light source is commonly a xenon flash lamp, or flashtube, which has a complex spectrum and a color temperature of approximately 5,600 kelvins. To obtain colored light, colored gels may be used.
Strobe lights usually use flashtubes with energy supplied from a capacitor, an energy storage device much like a battery, but capable of charging and releasing energy much faster.
In a capacitor-based strobe, the capacitor is charged up to around 300 V. Once the capacitor has been charged, to trigger the flash a small amount of power is diverted into a trigger transformer, a small transformer with a high turns ratio. This generates the weak but high-voltage spike required to ionize the xenon gas in a flash tube. An arc is created inside the tube, which acts as a path for the capacitor to discharge through, allowing the capacitor to quickly release its energy into the arc. The capacitor's energy rapidly heats the xenon gas, creating an extremely bright plasma discharge, which is seen as a flash.
A strobe without a capacitor storage device simply discharges mains voltages across the tube once it's fired. This type of strobe requires no charging time and allows for much quicker flash rates, but drastically reduces the lifetime of the flash tube if powered for significant periods of time. Such strobes require a form of current limiting, without which the flash tube would attempt to draw high currents from the electricity source, potentially tripping electrical breakers or causing voltage drops in the power supply line.
https://en.wikipedia.org/wiki/Strobe_light
Ultramarine is a deep blue color pigment which was originally made by grinding lapis lazuli into a powder.[2] The name comes from the Latin ultramarinus, literally 'beyond the sea', because the pigment was imported into Europe from mines in Afghanistan by Italian traders during the 14th and 15th centuries.[3]
Ultramarine was the finest and most expensive blue used by Renaissance painters. It was often used for the robes of the Virgin Mary, and symbolized holiness and humility. It remained an extremely expensive pigment until a synthetic ultramarine was invented in 1826.
https://en.wikipedia.org/wiki/Ultramarine
Sodalite (/ˈsoʊ.dəˌlaɪt/ SOH-də-lyte) is a royal blue tectosilicate mineral with the formula Na
8(Al
6Si
6O
24)Cl
2, widely used as an ornamental gemstone. Although massive sodalite samples are opaque, crystals are usually transparent to translucent. Sodalite is a member of the sodalite group with hauyne, nosean, lazurite and tugtupite.
First discovered by Europeans in 1811 in the Ilimaussaq intrusive complex in Greenland, sodalite did not become important as an ornamental stone until 1891 when vast deposits of fine material were discovered in Ontario, Canada.
A discontinuity of the thermal expansion coefficient occurs at a certain temperature when chloride is replaced by sulfate or iodide, and this is thought to happen when the framework becomes fully expanded or when the cation (sodium in natural sodalite) reaches the coordinates (1/4, 1/4, 1/4) (et cetera).[10] This adds symmetry (such as mirror planes in the faces of the unit cell) so that the space group becomes Pm3n (space group 223), and the cavities cease to be chiral and take on pyritohedral symmetry. Natural sodalite holds primarily chloride anions in the cages, but they can be substituted by other anions such as sulfate, sulfide, hydroxide, trisulfur with other minerals in the sodalite group representing end member compositions. The sodium can be replaced by other alkali group elements, and the chloride by other halides. Many of these have been synthesized.[10]
The characteristic blue color arises mainly from caged S−3 and S4 clusters.[11]
https://en.wikipedia.org/wiki/Sodalite
Opal is a hydrated amorphous form of silica (SiO2·nH2O); its water content may range from 3 to 21% by weight, but is usually between 6 and 10%. Because of its amorphous character, it is classed as a mineraloid, unlike crystalline forms of silica, which are classed as minerals. It is deposited at a relatively low temperature and may occur in the fissures of almost any kind of rock, being most commonly found with limonite, sandstone, rhyolite, marl, and basalt.
https://en.wikipedia.org/wiki/Opal
Onyx primarily refers to the parallel banded variety of the silicate mineral chalcedony. Agate and onyx are both varieties of layered chalcedony that differ only in the form of the bands: agate has curved bands and onyx has parallel bands. The colors of its bands range from black to almost every color. Commonly, specimens of onyx contain bands of black and/or white.[3] Onyx, as a descriptive term, has also been applied to parallel banded varieties of alabaster, marble, calcite, obsidian and opal, and misleadingly to materials with contorted banding, such as "Cave Onyx" and "Mexican Onyx".[4][5][6]
https://en.wikipedia.org/wiki/Onyx
Photochromism is the reversible transformation of a chemical species (photoswitch) between two forms by the absorption of electromagnetic radiation (photoisomerization), where the two forms have different absorption spectra.[1][2] In plain language, this can be described as a reversible change of colour upon exposure to light.
Tenebrescence[edit]
Tenebrescence, also known as reversible photochromism, is the ability of minerals to change colour when exposed to light. The effect can be repeated indefinitely, but is destroyed by heating.[9]
Tenebrescent minerals include hackmanite, spodumene and tugtupite.
Photochromic complexes[edit]
A photochromic complex is a kind of chemical compound that has photoresponsive parts on its ligand. These complexes have a specific structure: photoswitchable organic compounds are attached to metal complexes. For the photocontrollable parts, thermally and photochemically stable chromophores (azobenzene, diarylethene, spiropyran, etc.) are usually used. And for the metal complexes, a wide variety of compounds that have various functions (redox response, luminescence, magnetism, etc.) are applied.
The photochromic parts and metal parts are so close that they can affect each other's molecular orbitals. The physical properties of these compounds shown by parts of them (i.e., chromophores or metals) thus can be controlled by switching their other sites by external stimuli. For example, photoisomerization behaviors of some complexes can be switched by oxidation and reduction of their metal parts. Some other compounds can be changed in their luminescence behavior, magnetic interaction of metal sites, or stability of metal-to-ligand coordination by photoisomerization of their photochromic parts.
Classes of photochromic materials[edit]
Photochromic molecules can belong to various classes: triarylmethanes, stilbenes, azastilbenes, nitrones, fulgides, spiropyrans, naphthopyrans, spiro-oxazines, quinones and others.
https://en.wikipedia.org/wiki/Photochromism
Photosensitive glass, also known as photostructurable glass (PSG) or photomachinable glass, is a crystal-clear glass that belongs to the lithium-silicate family of glasses, in which an image of a mask[clarification needed] can be captured by microscopic metallic particles in the glass when it is exposed to short wave radiations such as ultraviolet light.[1] Photosensitive glass was first discovered by S. Donald Stookey in 1937.[2][3][4]
HF chemical etching[edit]
The lithium metasilicate that forms in the exposed regions of the glass has the unique property of being strongly etched in hydrofluoric acid (HF). Hence allowing a three-dimensional image of the mask to be produced, the resulting glass microstructures have a surface roughness in the range 5 μm[1] to 0.7 μm.[6]
X-ray sensitive glasses[edit]
As stated above radiation produces some direct and indirect measurable changes in the glasses. In some cases, the effect is readily observable immediately upon irradiation. In other cases, thermal treatment is required to bring about the observed changes. On the whole, the result of the mentioned reactions will be atomic silvers and/or silver clusters which act as nucleant for precipitation of lithium-meta-silicate during post heat-treatment of irradiated glass and Similar to other glass-ceramic systems, the more nucleation sites leads to more reduction of crystallization temperature and finer crystalline size. Therefore, to attain the above-mentioned condition, various energetic radiation such as UVand laser beam and x γ and proton and radiations have been used for different photosensitive glasses until now.[7] investigated the effect of X-ray irradiation on solarization of photosensitive lithium silicate based glasses containing cerium, antimony, tin and silver elements. They have shown that there is a possibility to use X-ray in photosensitive glasses. This will open new doors for nano machining of glasses in near future.
Applications[edit]
Photosensitive glass is used in printing and reproducing processes.[8] Photosensitive glass is like traditional camera film except that it reacts to ultraviolet (UV) light, where camera film responds to visible light.[4][9] The ideal wavelength to use for exposure should be between 300 and 350 nm, with 320 nm being optimum.[8]
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