query: which type of substance has the highest melting point

pos: Melting point of ice at 1 atmosphere of pressure is very close to ; this is also known as the ice point. In the presence of nucleating substances, the freezing point of water is not always the same as the melting point. In the absence of nucleators water can exist as a supercooled liquid down to −48.3 °C (−55 °F, 224.8 K) before freezing. The chemical element with the highest melting point is tungsten, at ; this property makes tungsten excellent for use as filaments in light bulbs. The often-cited carbon does not melt at ambient pressure but sublimes at about ;

pos: Incandescent light bulb direction. Compared to general-service bulbs, for the same power, these bulbs produce far more light, and (more importantly) light at a higher color temperature, at the expense of greatly reduced life (which may be as short as two hours for a type P1 lamp). The upper temperature limit for the filament is the melting point of the metal. Tungsten is the metal with the highest melting point, . A 50-hour-life projection bulb, for instance, is designed to operate only below that melting point. Such a lamp may achieve up to 22 lumens per watt, compared with 17.5 for a 750-hour

pos: Tungsten often brittle and hard to work. If made very pure, tungsten retains its hardness (which exceeds that of many steels), and becomes malleable enough that it can be worked easily. It is worked by forging, drawing, or extruding. Tungsten objects are also commonly formed by sintering. Of all metals in pure form, tungsten has the highest melting point (3422 °C, 6192 °F), lowest vapor pressure (at temperatures above 1650 °C, 3000 °F), and the highest tensile strength. Although carbon remains solid at higher temperatures than tungsten, carbon sublimes at atmospheric pressure instead of melting, so it has no melting point.

pos: Tantalum-tungsten alloys Tantalum-tungsten alloys Tantalum-tungsten alloys are in the refractory metals group, keeping their chemical and physical properties the same at high temperatures. The tantalum-tungsten alloys are characterized by their high melting point and the tension resistance. The properties of the final alloy are a combination of properties from the two elements: tungsten, the element with the highest melting point in the periodic table, and tantalum which has high corrosion resistance. The Tantalum-Tungsten alloys typically vary in their percentage of Tungsten. Some common variants are: The alloys of tantalum-tungsten have high corrosion resistance, and refractory properties. The crystalline structure of the material

pos: Melting point of ice at 1 atmosphere of pressure is very close to ; this is also known as the ice point. In the presence of nucleating substances, the freezing point of water is not always the same as the melting point. In the absence of nucleators water can exist as a supercooled liquid down to −48.3 °C (−55 °F, 224.8 K) before freezing. The chemical element with the highest melting point is tungsten, at ; this property makes tungsten excellent for use as filaments in light bulbs. The often-cited carbon does not melt at ambient pressure but sublimes at about ;

pos: Langmuir probe the general case of none-Maxwellian electron distribution functions see. For laboratory and technical plasmas, the electrodes are most commonly tungsten or tantalum wires several thousandths of an inch thick, because they have a high melting point but can be made small enough not to perturb the plasma. Although the melting point is somewhat lower, molybdenum is sometimes used because it is easier to machine and solder than tungsten. For fusion plasmas, graphite electrodes with dimensions from 1 to 10 mm are usually used because they can withstand the highest power loads (also sublimating at high temperatures rather than melting), and

pos: Flashtube the electrodes are usually made of tungsten, which has the highest melting point of any metal, to handle the thermionic emission of electrons. Cathodes are often made from porous tungsten filled with a barium compound, which gives low work function; the structure of cathode has to be tailored for the application. Anodes are usually made from pure tungsten, or, when good machinability is required, lanthanum-alloyed tungsten, and are often machined to provide extra surface area to cope with power loading. DC arc lamps often have a cathode with a sharp tip, to help keep the arc away from the glass

pos: Period 6 element living organism. Tungsten interferes with molybdenum and copper metabolism, and is somewhat toxic to animal life. Rhenium is a chemical element with the symbol Re and atomic number 75. It is a silvery-white, heavy, third-row transition metal in group 7 of the periodic table. With an "estimated" average concentration of 1 part per billion (ppb), rhenium is one of the rarest elements in the Earth's crust. The free element has the third-highest melting point and highest boiling point of any element. Rhenium resembles manganese chemically and is obtained as a by-product of molybdenum and copper ore's extraction and refinement. Rhenium

neg: Melting point graphically to the right, but also of Si, Ge, Ga, Bi. With extremely large changes in pressure, substantial changes to the melting point are observed. For example, the melting point of silicon at ambient pressure (0.1 MPa) is 1415 °C, but at pressures in excess of 10 GPa it decreases to 1000 °C. Melting points are often used to characterize organic and inorganic compounds and to ascertain their purity. The melting point of a pure substance is always higher and has a smaller range than the melting point of an impure substance or, more generally, of mixtures. The higher the

neg: Melting point Open melting point data are also available from "Nature Precedings". High quality data mined from patents and also models developed with these data were published by Tetko "et al". Melting point The melting point (or, rarely, liquefaction point) of a substance is the temperature at which it changes state from solid to liquid. At the melting point the solid and liquid phase exist in equilibrium. The melting point of a substance depends on pressure and is usually specified at a standard pressure such as 1 atmosphere or 100 kPa. When considered as the temperature of the reverse change from liquid

neg: Melting point Melting point The melting point (or, rarely, liquefaction point) of a substance is the temperature at which it changes state from solid to liquid. At the melting point the solid and liquid phase exist in equilibrium. The melting point of a substance depends on pressure and is usually specified at a standard pressure such as 1 atmosphere or 100 kPa. When considered as the temperature of the reverse change from liquid to solid, it is referred to as the freezing point or crystallization point. Because of the ability of some substances to supercool, the freezing point is not considered as

neg: Melting-point apparatus Melting-point apparatus A melting-point apparatus is a scientific instrument used to determine the melting point of a substance. Some types of melting-point apparatuses include the Thiele tube, Fisher-Johns apparatus, Gallenkamp (Electronic) melting-point apparatus and automatic melting-point apparatus. While the outward designs of apparatuses can vary greatly, most apparatuses use a sample loaded into a sealed capillary ("melting-point capillary"), which is then placed in the apparatus. The sample is then heated, either by a heating block or an oil bath, and as the temperature increases, the sample is observed to determine when the phase change from solid to liquid occurs. The

neg: Melting point a characteristic property of a substance. When the "characteristic freezing point" of a substance is determined, in fact the actual methodology is almost always "the principle of observing the disappearance rather than the formation of ice", that is, the melting point. For most substances, melting and freezing points are approximately equal. For example, the melting point "and" freezing point of mercury is 234.32 kelvins (−38.83 °C or −37.89 °F). However, certain substances possess differing solid-liquid transition temperatures. For example, agar melts at 85 °C (185 °F) and solidifies from ; such direction dependence is known as hysteresis. The melting point

neg: Carbon the softest known substances, and diamond, the hardest naturally occurring substance. It bonds readily with other small atoms, including other carbon atoms, and is capable of forming multiple stable covalent bonds with suitable multivalent atoms. Carbon is known to form almost ten million different compounds, a large majority of all chemical compounds. Carbon also has the highest sublimation point of all elements. At atmospheric pressure it has no melting point, as its triple point is at and , so it sublimes at about 3,900 K. Graphite is much more reactive than diamond at standard conditions, despite being more thermodynamically stable,

neg: Panicudine data, confirmed by high resolution mass spectrometry, completed the determination of the structure. Panicudine was identified as an active antimicrobial substance in the chloroform extract of "Polygonum aviculare", a traditional herbal medicine of the Mediterranean coastal region. It has also been isolated from epigeal parts of "Rumex pictus". A variety of related alkaloids have been isolated from other natural sources. Panicudine Panicudine (6-hydroxy-11-deoxy-13-dehydrohetisane) is a C-diterpene alkaloid of the hetisine type, first isolated from "Aconitum paniculatum". It has empirical formula CHNO and a melting point of 249-250 °C. The structure was determined to be a hetisine type diterpene by noting

neg: Polypropylene styrene (ABS). Polypropylene is reasonably economical. Polypropylene has good resistance to fatigue. The melting point of polypropylene occurs in a range, so the melting point is determined by finding the highest temperature of a differential scanning calorimetry chart. Perfectly isotactic PP has a melting point of . Commercial isotactic PP has a melting point that ranges from , depending on atactic material and crystallinity. Syndiotactic PP with a crystallinity of 30% has a melting point of . Below 0 °C, PP becomes brittle. The thermal expansion of polypropylene is very large, but somewhat less than that of polyethylene. Polypropylene at

neg: Solidus (chemistry) Solidus (chemistry) In chemistry, materials science, and physics, the solidus is the locus of temperatures (a curve on a phase diagram) below which a given substance is completely solid (crystallized). The solidus is applied, among other materials, to metal alloys, ceramics, and natural rocks and minerals. The solidus quantifies the temperature at which melting of a substance "begins", but the substance is not necessarily melted "completely", i.e., the solidus is not necessarily a melting point. For this distinction, the solidus may be contrasted to the liquidus. The solidus is always less than or equal to the liquidus, but they need

neg: Melting point "ΔH" are respectively the temperature at the melting point, change of entropy of melting and the change of enthalpy of melting. The melting point is sensitive to extremely large changes in pressure, but generally this sensitivity is orders of magnitude less than that for the boiling point, because the solid-liquid transition represents only a small change in volume. If, as observed in most cases, a substance is more dense in the solid than in the liquid state, the melting point will increase with increases in pressure. Otherwise the reverse behavior occurs. Notably, this is the case of water, as illustrated

neg: Melting Melting Melting, or fusion, is a physical process that results in the phase transition of a substance from a solid to a liquid. This occurs when the internal energy of the solid increases, typically by the application of heat or pressure, which increases the substance's temperature to the melting point. At the melting point, the ordering of ions or molecules in the solid breaks down to a less ordered state, and the solid melts to become a liquid. Substances in the molten state generally have reduced viscosity as the temperature increases. An exception to this principle is the element sulfur,

neg: Carbon dioxide clathrate Carbon dioxide clathrate Carbon dioxide hydrate is a snow-like crystalline substance composed of water ice and carbon dioxide. It normally is a Type I gas clathrate. However, there has been some experimental evidence for the development of a metastable Type II phase at A temperature near the ice melting point. The clathrate can exist below 283K (10 °C) at a range of pressures of carbon dioxide. It is quite likely to be important on Mars due to the presence of carbon dioxide and ice at low temperatures. The first evidence for the existence of CO hydrates dates back to the

neg: Enthalpy of fusion change in volume by displacing its environment against ambient pressure. The temperature at which the phase transition occurs is the melting point or the freezing point, according to context. By convention, the pressure is assumed to be unless otherwise specified. The 'enthalpy' of fusion is a latent heat, because during melting the heat energy needed to change the substance from solid to liquid at atmospheric pressure is latent heat of fusion, as the temperature remains constant during the process. The latent heat of fusion is the enthalpy change of any amount of substance when it melts. When the heat of

neg: Lauric acid other soaps. In the laboratory, lauric acid may be used to investigate the molar mass of an unknown substance via the freezing-point depression. The choice of lauric acid is convenient because the melting point of the pure compound is relatively high (43.8°C). Its cryoscopic constant is 3.9°C·kg/mol. By melting lauric acid with the unknown substance, allowing it to cool, and recording the temperature at which the mixture freezes, the molar mass of the unknown compound may be determined. "In vitro" experiments have suggested that some fatty acids including lauric acid could be a useful component in a treatment for acne,

neg: Entropy of fusion Equilibrium occurs when the temperature is equal to the melting point formula_4 so that and the entropy of fusion is the heat of fusion divided by the melting point. Helium-3 has a negative entropy of fusion at temperatures below 0.3 K. Helium-4 also has a very slightly negative entropy of fusion below 0.8 K. This means that, at appropriate constant pressures, these substances freeze with the addition of heat. Entropy of fusion The entropy of fusion is the increase in entropy when melting a substance. This is almost always positive since the degree of disorder increases in the transition from

neg: Electroless nickel Unlike electroplated nickel, electroless nickel deposits do not have a precise melting point but rather have a melting "range". Pure nickel has a melting point of 1455 °C (2650 °F), however EN is an alloy and as the phosphorus content is increased within the film, the deposit begins to soften at lower temperatures and continues to soften until it eventually melts. The melting range decreases linearly as the phosphorus levels increase. The eutectic or lowest melting point for NiP alloys is 880 °C (1620 °F) and occurs at a deposit phosphorus content of 11% b.w. The highest melting point is

neg: Melting sufficient rigidity to mechanically withstand load. Under a standard set of conditions, the melting point of a substance is a characteristic property. The melting point is often equal to the freezing point. However, under carefully created conditions, supercooling or superheating past the melting or freezing point can occur. Water on a very clean glass surface will often supercool several degrees below the freezing point without freezing. Fine emulsions of pure water have been cooled to −38 degrees Celsius without nucleation to form ice. Nucleation occurs due to fluctuations in the properties of the material. If the material is kept still

neg: Refractory metals including all elements with a melting point above , includes a varying number of nine additional elements: titanium, vanadium, chromium, zirconium, hafnium, ruthenium, rhodium, osmium and iridium. The artificial elements, being radioactive, are never considered to be part of the refractory metals, although technetium has a melting point of 2430 K or 2157 °C and rutherfordium is predicted to have melting point of 2400 K or 2100 °C. The melting point of the refractory metals are the highest for all elements except carbon, osmium and iridium. This high melting point defines most of their applications. All the metals are body-centered

neg: Phase diagram the solid and liquid phases have the same symmetry group. For most substances, the solid–liquid phase boundary (or fusion curve) in the phase diagram has a positive slope so that the melting point increases with pressure. This is true whenever the solid phase is denser than the liquid phase. The greater the pressure on a given substance, the closer together the molecules of the substance are brought to each other, which increases the effect of the substance's intermolecular forces. Thus, the substance requires a higher temperature for its molecules to have enough energy to break out of the fixed pattern

neg: Barium metaphosphate and barium polyphosphate forms a low-melting glass with a high coefficient of thermal expansion. The melting point of the glass increases with barium content. This glass makes seals with low melting metals like aluminium (melting point 650 °C). Normal borosilicate glasses soften above the melting point of aluminium. This mixture is prepared by heating a mixture of diammonium phosphate, sodium carbonate, and barium carbonate. Barium metaphosphate Barium metaphosphate is an inorganic substance with the molecular formula Ba(PO). It is a colourless solid that is insoluble in water, though is soluble in acidic solutions through "slow dissolution". X-ray crystallography shows that

neg: Rheid Rheid In geology, a rheid is a substance whose temperature is below the melting point and whose deformation by viscous flow during the time of observation is at least three orders of magnitude (1,000×) greater than the elastic deformation under the given conditions. A material is a rheid by virtue of the time of observation. The term, coined by S. Warren Carey in 1953, has the same Greek root as rheology, the science of viscoelasticity and nonlinear flow. Almost any type of rock can behave as a rheid under appropriate conditions of temperature and pressure. For example, the Earth's mantle

neg: Flux melting the mantle, where these volatiles are released by metamorphic dewatering into the overlying mantle wedge. The partial melting triggered by the incorporation of volatiles produces mafic magma which rises and differentiates forming the igneous and volcanic rocks of the overlying volcanic arc. Flux melting In igneous petrology, flux melting occurs when water and other volatile components are added to hot solid rock. In engineering and metallurgy, flux is a substance, such as salt, that produces a low melting point mixture with a metal oxide. In the same way, the addition of water and other volatile compounds to rocks composed of

neg: Heat transfer of "gas thermal barrier". Condensation occurs when a vapor is cooled and changes its phase to a liquid. During condensation, the latent heat of vaporization must be released. The amount of the heat is the same as that absorbed during vaporization at the same fluid pressure. There are several types of condensation: Melting is a thermal process that results in the phase transition of a substance from a solid to a liquid. The internal energy of a substance is increased, typically with heat or pressure, resulting in a rise of its temperature to the melting point, at which the ordering

neg: Niobium a body-centered cubic crystal structure from absolute zero to its melting point, high-resolution measurements of the thermal expansion along the three crystallographic axes reveal anisotropies which are inconsistent with a cubic structure. Therefore, further research and discovery in this area is expected. Niobium becomes a superconductor at cryogenic temperatures. At atmospheric pressure, it has the highest critical temperature of the elemental superconductors at 9.2 K. Niobium has the greatest magnetic penetration depth of any element. In addition, it is one of the three elemental Type II superconductors, along with vanadium and technetium. The superconductive properties are strongly dependent on the

neg: Compounds of fluorine negative balls that fluorines are repel each other. Therefore, the intermolecular bonding strength falls further down, a result of which is the low melting point of high fluorides. Fluorine combines with hydrogen to make a compound (HF) called hydrogen fluoride or, especially in the context of water solutions, hydrofluoric acid. The H-F bond type is one of the few capable of hydrogen bonding (creating extra clustering associations with similar molecules). This influences various peculiar aspects of hydrogen fluoride's properties. In some ways the substance behaves more like water, also very prone to hydrogen bonding, than one of the other hydrogen

neg: Chemical substance FeS. The resulting compound has all the properties of a chemical substance and is not a mixture. Iron(II) sulfide has its own distinct properties such as melting point and solubility, and the two elements cannot be separated using normal mechanical processes; a magnet will be unable to recover the iron, since there is no metallic iron present in the compound. While the term "chemical substance" is a precise technical term that is synonymous with "chemical" for chemists, the word "chemical" is used in general usage in the English speaking world to refer to both (pure) chemical substances and mixtures (often

neg: Homologous temperature values for tensile strength, shear strength and modulus of elasticity. Copper, on the other hand, has a much higher melting point, so foils are working at only 0.16T to 0.29T and their properties are little affected by temperature. Homologous temperature Homologous temperature expresses the temperature of a material as a fraction of its melting point temperature using the Kelvin scale: formula_1 For example, the homologous temperature of lead at room temperature (25 °C) is approximately 0.50 (T = T/T = 298 K/601 K = 0.50). The homologous temperature of a substance is useful for determining the rate of steady state

neg: Thermodynamic temperature box heading from blue to green. At one specific thermodynamic point, the melting point (which is 0 °C across a wide pressure range in the case of water), all the atoms or molecules are, on average, at the maximum energy threshold their chemical bonds can withstand without breaking away from the lattice. Chemical bonds are all-or-nothing forces: they either hold fast, or break; there is no in-between state. Consequently, when a substance is at its melting point, every joule of added thermal energy only breaks the bonds of a specific quantity of its atoms or molecules, converting them into a

neg: Cocrystal the properties of the individual components. Such properties include melting point, solubility, chemical stability, and mechanical properties. Some cocrystals have been observed to exist as polymorphs, which may display different physical properties depending on the form of the crystal. Phase diagrams determined from the "contact method" of thermal microscopy is valuable in the detection of cocrystals. The construction of these phase diagrams is made possible due to the change in melting point upon cocrystallization. Two crystalline substances are deposited on either side of a microscope slide and are sequentially melted and resolidified. This process creates thin films of each substance

neg: Liquefaction transformed into a substance that acts like a liquid, often in an earthquake. Soil liquefaction blamed for building collapses in the city of Palu, Indonesia in October 2018. In a related phenomena, liquefaction of bulk materials in cargo ships may cause a dangerous shift in the load. In physics and chemistry, the phase transitions from solid and gas to liquid (melting and condensation, respectively) may be referred to as liquefaction. The melting point (sometimes called liquefaction point) is the temperature and pressure at which a solid becomes a liquid. In commercial and industrial situations, the process of condensing a gas

neg: Melting amorphous materials. Even below its melting point, quasi-liquid films can be observed on crystalline surfaces. The thickness of the film is temperature dependent. This effect is common for all crystalline materials. Pre-melting shows its effects in e.g. frost heave, the growth of snowflakes and, taking grain boundary interfaces into account, maybe even in the movement of glaciers. In genetics, melting DNA means to separate the double-stranded DNA into two single strands by heating or the use of chemical agents, cf. polymerase chain reaction. Melting Melting, or fusion, is a physical process that results in the phase transition of a substance

neg: Melting point a liquid phase only exists above pressures of and estimated (see ). Tantalum hafnium carbide (TaHfC) is a refractory compound with a very high melting point of 4215 K (3942 °C, 7128 °F). At the other end of the scale, helium does not freeze at all at normal pressure even at temperatures close to absolute zero; a pressure of more than twenty times normal atmospheric pressure is necessary. Many laboratory techniques exist for the determination of melting points. A Kofler bench is a metal strip with a temperature gradient (range from room temperature to 300 °C). Any substance can be

neg: Nitrocyclohexane Nitrocyclohexane Nitrocyclohexane is an organic compound with the molecular formula CHNO. It is listed as an extremely hazardous substance by the Emergency Planning and Community Right-to-Know Act, and the NOAA warns that it can be explosive. It is a colorless liquid, or a pale yellow liquid. At standard temperature and pressure, it is a liquid, and has a melting point of -34 °C, and a boiling point of 205.8 °C. Its density is 1.061 g/cm, and it is slightly soluble in water. Nitrocyclohexane is highly flammable and a strong oxidizing agent. It is listed as an extremely hazardous substance by

neg: Flux melting Flux melting In igneous petrology, flux melting occurs when water and other volatile components are added to hot solid rock. In engineering and metallurgy, flux is a substance, such as salt, that produces a low melting point mixture with a metal oxide. In the same way, the addition of water and other volatile compounds to rocks composed of silicate minerals lowers the melting temperature of those rocks. In subduction zones, the ultramafic rock of the upper mantle is melted by the addition of volatiles from the down-going plate. The subducting slab of oceanic crust carries water and other volatiles into

neg: 1,3-Difluoro-trisulfane-1,1-difluoride Possible isomers of SF includes FSSFSF, which has a spontaneous fluorine migration to yield FSSSF which in turn spontaneously fragments to SF and SSF. Another high energy structure is a ring consisting of three SF units. 1,3-Difluoro-trisulfane-1,1-difluoride 1,3-Difluoro-trisulfane-1,1-difluoride is an inorganic molecular substance consisting of sulfur in a low oxidation state with fluorine. The structural formula is SFSSF containing a chain of three sulfur atoms. At one end there are three fluorine atoms bound, and at the other one. The formula can also be written SF. It has a melting point of -62°C and a boiling point of 94°C. As

neg: Thermal decomposition break less easily. For example, copper is near the bottom of the reactivity series, and copper sulfate (CuSO), begins to decompose at about 200 °C, increasing rapidly at higher temperatures to about 560 °C. In contrast potassium is near the top of the reactivity series, and potassium sulfate (KSO) does not decompose at its melting point of about 1069 °C, nor even at its boiling point. Thermal decomposition Thermal decomposition, or thermolysis, is a chemical decomposition caused by heat. The decomposition temperature of a substance is the temperature at which the substance chemically decomposes. The reaction is usually endothermic as

neg: Krüss Optronic may be delivered through different computer interfaces. The melting point is specific characteristic of a substance. A.Krüss Optronic provides a fully automatic melting point meter for powdery substances. With the device, melting points up to 400 °C can be examined. Beside these main product groups, A.Krüss Optronic offers a variety of laboratory equipment, like flame-photometers, devices for spectral measurements, UV and analysis lamps, color sensors, and lab-software. A specialty of A.Krüss Optronic is their program of gemological instruments and equipment. It includes gemological magnifiers and microscopes, special spectrometers and gem-refractometers, and complete battery-operated portable laboratories for field operation. Krüss Optronic

neg: Melting tank purchasing a candle or soap. Melting tanks are generally classified as either direct-heating or water-jacket-heating. There is another type of melter which uses convection heating similar to an oven. These are generally more expensive than normal heaters, even though they are inefficient and take a longer time to heat, simply because they rely on air to heat. Direct-heat melters are generally made from aluminum and can heat up to over 500°F. The uses vary from wax to solder. They heat with the heating element directly on the aluminum which is directly against the substance to be melted, hence the name

neg: Alkali metal changes state from solid to liquid while the boiling point of a substance (in liquid state) is the point where the vapour pressure of the liquid equals the environmental pressure surrounding the liquid and all the liquid changes state to gas. As a metal is heated to its melting point, the metallic bonds keeping the atoms in place weaken so that the atoms can move around, and the metallic bonds eventually break completely at the metal's boiling point. Therefore, the falling melting and boiling points of the alkali metals indicate that the strength of the metallic bonds of the alkali

neg: Pressure melting point flux from below and atmospheric warming or cooling from above. As the pressure increases with depth in a glacier from the weight of the ice above, the pressure melting point of ice decreases within bounds, as shown in the diagram. The level where ice can start melting is where the pressure melting point equals the actual temperature. In static equilibrium conditions, this would be the highest level where water can exist in a glacier. It would also be the level of the base of an ice shelf, or the ice-water interface of a subglacial lake. Pressure melting point The pressure

neg: Ascaridole study by E. K. Nelson in 1911, in particular that ascaridole explodes upon heating, reacting with sulfuric, hydrochloric, nitric, or phosphoric acids. Nelson showed that the new substance contained neither a hydroxyl nor a carbonyl group and that upon reduction with iron(II) sulfate it formed a glycol, now known as ascaridole glycol, CHO. The glycol is more stable than ascaridole and has a higher melting point of about 64 °C, boiling point of 272 °C, and density of 1.098 g/cm. Nelson also predicted the chemical structure of ascaridole which was almost correct, but had the peroxide bridge not along the

neg: Type metal melting point of pure antimony is 630 °C, this mixture will be completely molten and a homogeneous fluid even at temperatures as low as 371 °C. Letting this mixture cool the alloy will remain liquid even through 355 °C, the melting point of pure lead. Once the temperature reaches 291 °C, lead crystals will start to form, increasing the cohesion of the liquid alloy. At 252 °C, the mixture will start to fully solidify, during which the temperature will remain constant. Only when the mixture has fully solidified will the temperature start to decrease again. Using a 10% antimony, 90%

neg: Tableting These devices use strain gauge technology at each compression station to monitor pressure, which is then calibrated to tablet weight. And can be affected by a number of factor In almost all cases, tablets coming out of a tablet machine have excess powder on their surface which is removed by passing them through a tablet deduster. The Fette machine is a device that chills the compression components to allow the compression of low melting point substance such as waxes and thereby making it possible to compress product with low melting points. Compressed tablets can be round, oblong, or unique in

neg: Votive candle type of candle being made. The speed at which the candle burns depends on the composition of the wax. A taper candle that sits in a ring-shaped candle holder may have a low melting point and produce little to no oil, whereas a votive candle set in a glass cup may have a very low melting point and turn to oil. Pillar candles, large candles often with multiple wicks, have their own formula. Soy jar candles tend to have a lower melting point than pillars and votive candles. Candle quality also varies widely depending on the candle maker. The aroma

neg: Thermodynamic temperature large amount of latent heat is liberated as steam condenses into liquid water on the skin. Even though thermal energy is liberated or absorbed during phase transitions, pure chemical elements, compounds, and eutectic alloys "exhibit no temperature change whatsoever" while they undergo them (see "Fig. 7," below right). Consider one particular type of phase transition: melting. When a solid is melting, crystal lattice chemical bonds are being broken apart; the substance is transitioning from what is known as a "more ordered state" to a "less ordered state". In "Fig. 7, "the melting of ice is shown within the lower left

neg: Metoprolol and a small percentage by CYP3A4, resulting in inactive metabolites. Metoprolol has a very low melting point; around for the tartrate, and around for the succinate. Because of this, metoprolol is always manufactured in a salt-based solution, as drugs with low melting points are difficult to work with in a manufacturing environment. The free base exists as a waxy white solid, and the tartrate salt is finer crystalline material. The active substance metoprolol is employed either as metoprolol succinate or as metoprolol tartrate (where 100 mg metoprolol tartrate corresponds to 95 mg metoprolol succinate). The tartrate is an immediate-release formulation

neg: Twinwall plastic begin to move again, allowing crystals to nucleate and grow. This procedure is known as solid-state crystallization. Structure<br> Polyethylene is a thermoplastic polymer consisting of long hydrocarbon chains. Depending on the crystallinity and molecular weight, a melting point and glass transition may or may not be observable. The temperature at which these occur varies strongly with the type of polyethylene. For common commercial grades of medium- and high-density polyethylene the melting point is typically in the range . The melting point for average, commercial, low-density polyethylene is typically . Most LDPE, MDPE and HDPE grades have excellent chemical resistance, meaning

neg: Phase rule separation into two phases. Above the critical point and away from the phase boundary curve, and the temperature and pressure can be controlled independently. Hence there is only one phase, and it has the physical properties of a dense gas, but is also referred to as a supercritical fluid. Of the other two-boundary curves, one is the solid–liquid boundary or melting point curve which indicates the conditions for equilibrium between these two phases, and the other at lower temperature and pressure is the solid–gas boundary. Even for a pure substance, it is possible that three phases, such as solid, liquid

neg: Beilstein database the product name "Reaxys". The database contains information on reactions, substances, structures and properties. Up to 350 fields containing chemical and physical data (such as melting point, refractive index etc.) are available for each substance. References to the literature in which the reaction or substance data appear are also given. The Beilstein content made available through Reaxys is complemented by information drawn from Gmelin (which gives access to the Gmelin Database), a very large repository of organometallic and inorganic information, as well as by information drawn from the Patent Chemistry Database. The Reaxys registered trademark and the database itself are

neg: Phenylketonuria of the same substance he had found in eight other patients. He conducted tests and found reactions that gave rise to benzaldehyde and benzoic acid, which led him to conclude that the compound contained a benzene ring. Further testing showed the melting point to be the same as phenylpyruvic acid, which indicated that the substance was in the urine. In 1954, Horst Bickel, Evelyn Hickmans and John Gerrard published a paper that described how they created a diet that was low in phenylalanine and the patient recovered. Bickel, Gerrard and Hickmans were awarded the John Scott Medal in 1962 for

neg: Tantalum hafnium carbide Tantalum hafnium carbide Tantalum hafnium carbide is a refractory chemical compound with a general formula TaHfC, which can be considered as a solid solution of tantalum carbide and hafnium carbide. Individually, these two carbides have the highest melting points among the binary compounds, and , respectively, and their "alloy" with a composition TaHfC is believed to have a melting point of . Very few measurements of melting point in tantalum hafnium carbide have been reported, because of the obvious experimental difficulties at extreme temperatures. A 1965 study of the TaC-HfC solid solutions at temperatures 2225–2275 °C found a minimum in

neg: Thiele tube ranges at which the sample melts can then be observed. During heating, the point at which melting is observed and the temperature constant is the melting point of the sample. A more modern method uses dedicated equipment, known as a melting point apparatus. A slow heating rate at the melting point is needed in order to get an accurate measurement. Record the temperature on the thermometer when the sample starts to melt and record the temperature again when all of the sample has melted (this gives you the melting point range, which is what is usually quoted in chemical literature).

neg: High-temperature corrosion High-temperature corrosion High-temperature corrosion is a mechanism of corrosion that takes place in gas turbines, diesel engines, furnaces or other machinery coming in contact with hot gas containing certain contaminants. Fuel sometimes contains vanadium compounds or sulfates which can form compounds during combustion having a low melting point. These liquid melted salts are strongly corrosive for stainless steel and other alloys normally inert against the corrosion and high temperatures. Other high-temperature corrosions include high-temperature oxidation, sulfidation and carbonization. Two types of sulfate-induced hot corrosion are generally distinguished: Type I takes place above the melting point of sodium sulfate and Type

neg: Francium has a half-life of 56 seconds, although synthetic astatine-210 is much longer-lived with a half-life of 8.1 hours. All isotopes of francium decay into astatine, radium, or radon. Francium-223 also has a shorter half-life than the longest-lived isotope of each synthetic element up to and including element 105, dubnium. Francium is an alkali metal whose chemical properties mostly resemble those of caesium. A heavy element with a single valence electron, it has the highest equivalent weight of any element. Liquid francium—if created—should have a surface tension of 0.05092 N/m at its melting point. Francium's melting point was calculated to be

neg: Melting point medium is then removed and the current through the filament is adjusted to match the filament intensity to that of the black-body. This establishes a second calibration point for the pyrometer. This step is repeated to carry the calibration to higher temperatures. Now, temperatures and their corresponding pyrometer filament currents are known and a curve of temperature versus current can be drawn. This curve can then be extrapolated to very high temperatures. In determining melting points of a refractory substance by this method, it is necessary to either have black body conditions or to know the emissivity of the material

neg: Rubidium nor under the microscope showed the slightest trace of metallic substance." They presumed it was a subchloride (); however, the product was probably a colloidal mixture of the metal and rubidium chloride. In a second attempt to produce metallic rubidium, Bunsen was able to reduce rubidium by heating charred rubidium tartrate. Although the distilled rubidium was pyrophoric, they were able to determine the density and the melting point. The quality of this research in the 1860s can be appraised by the fact that their determined density differs less than 0.1 g/cm and the melting point by less than 1 °C

neg: Polymorphism (materials science) analogous phenomenon for amorphous materials is polyamorphism, when a substance can take on several different amorphous modifications. In terms of thermodynamics, there are two types of polymorphic behaviour. For a monotropic system, a plot of the free energy of the various polymorphs against temperature do not cross before all polymorphs melt—in other words, any transition from one polymorph to another below melting point will be irreversible. For an enantiotropic system, a plot of the free energy against temperature shows a crossing point threshold before the various melting points. It may also be possible to revert interchangeably between the two polymorphs

neg: Thermodynamic databases for pure substances mass and amount composition and transition temperatures of the constituent elements. Transition temperatures for the constituent elements have dashes ------- in the first column in a blank row, such as at 922 K, the melting point of Mg. Transition temperatures for the substance have two blank rows with dashes, and a center row with the defined transition and the enthalpy change, such as the melting point of MgCl at 980 K. The datafile equations are at the bottom of the table, and the entire table is in an Excel worksheet. This is particularly useful when the data is intended for

neg: Aspirin occasionally phosphoric acid) are almost always used as a catalyst. This method is commonly employed in undergraduate teaching labs. Formulations containing high concentrations of aspirin often smell like vinegar because aspirin can decompose through hydrolysis in moist conditions, yielding salicylic and acetic acids. Aspirin, an acetyl derivative of salicylic acid, is a white, crystalline, weakly acidic substance, with a melting point of , and a boiling point of . Its acid dissociation constant (p"K") is 3.5 at . Polymorphism, or the ability of a substance to form more than one crystal structure, is important in the development of pharmaceutical ingredients.

neg: Asphalt asphalt concrete, which has only around 5% asphalt. This thermoplastic substance is widely used in the building industry for waterproofing flat roofs and tanking underground. Mastic asphalt is heated to a temperature of and is spread in layers to form an impervious barrier about thick. A number of technologies allow asphalt to be mixed at much lower temperatures. These involve mixing with petroleum solvents to form "cutbacks" with reduced melting point or mixing with water to turn the asphalt into an emulsion. Asphalt emulsions contain up to 70% asphalt and typically less than 1.5% chemical additives. There are two main

neg: Vacancy defect Vacancy defect In crystallography, a vacancy is a type of point defect in a crystal. Crystals inherently possess imperfections, sometimes referred to as crystalline defects. A defect in which an atom is missing from one of the lattice sites is known as a "vacancy" defect. It is also known as a Schottky defect, although in ionic crystals the concepts are not identical. Vacancies occur naturally in all crystalline materials. At any given temperature, up to the melting point of the material, there is an equilibrium concentration (ratio of vacant lattice sites to those containing atoms). At the melting point of

neg: Melting point point (typically considered to be above, say, 1800 °C) may be determined by heating the material in a black body furnace and measuring the black-body temperature with an optical pyrometer. For the highest melting materials, this may require extrapolation by several hundred degrees. The spectral radiance from an incandescent body is known to be a function of its temperature. An optical pyrometer matches the radiance of a body under study to the radiance of a source that has been previously calibrated as a function of temperature. In this way, the measurement of the absolute magnitude of the intensity of radiation

neg: Lanthanide contraction and ionic radii does affect their chemistry, however. Without the lanthanide contraction, a chemical separation of lanthanides would be extremely difficult. However, this contraction makes the chemical separation of period 5 and period 6 transition metals of the same group rather difficult. There is a general trend of increasing Vickers hardness, Brinell hardness, density and melting point from lanthanum to lutetium (with europium and ytterbium being the most notable exceptions; in the metallic state, they are divalent rather than trivalent). Lutetium is the hardest and densest lanthanide and has the highest melting point. The elements following the lanthanides in the

neg: Polyethylene fibers. It feels waxy when touched. The commercial applicability of polyethylene is limited by its comparably low melting point. For common commercial grades of medium- and high-density polyethylene the melting point is typically in the range . The melting point for average, commercial, low-density polyethylene is typically . These temperatures vary strongly with the type of polyethylene. Polyethylene consists of nonpolar, saturated, high molecular weight hydrocarbons. Therefore, its chemical behavior is similar to paraffin. The individual macromolecules are not covalently linked. Because of their symmetric molecular structure, they tend to crystallize; overall polyethylene is partially crystalline. Higher crystallinity increases density

neg: Pulverized Vinsol resin Pulverized Vinsol resin Pulverized Vinsol resin (PV resin) is a substance that is extracted from pinewood stumps. It has a dark brown color and a high melting point. It is a thermoplastic natural resin. Vinsol is produced exclusively by Pinova, Inc. in Brunswick, Georgia, USA. Because of its physical and chemical properties and its aliphatic-hydrocarbon insolubility, Vinsol resin is used in a wide range of industrial applications. In a finely ground state it is used for testing filters for clogging. e.g. in accordance with SAE HS 806. The powder which is free-flowing may be suspended in a liquid for testing

neg: Chondrite Type 7 chondrites have experienced the highest temperatures possible, short of that required to produce melting. Should the onset of melting occur the meteorite would probably be classified as a primitive achondrite instead of a chondrite. All groups of ordinary and enstatite chondrites, as well as R and CK chondrites, show the complete metamorphic range from type 3 to 6. CO chondrites comprise only type 3 members, although these span a range of petrologic types from 3.0 to 3.8. These meteorites either contain a proportion of water or minerals that have been altered by water. This suggests that the asteroid

neg: Cashmeran substance Cashmeran Cashmeran (trade name; also known as musk indanone or indomuscone; chemical name 6,7-dihydro-1,1,2,3,3-pentamethyl-4(5"H")-indanone or DPMI) is a chemical compound used in fragrances. Cashmeran is an alicyclic ketone with the molecular formula CHO and a molecular weight of 206 g/mol. At room temperature it occurs as a white solid but its melting point is 27 °C. Boiling point has been reported to be 256 °C, however in some tests decomposition of the material was noted at 220 °C. Cashmeran was discovered by International Flavors and Fragrances in the 1970s by John Hall. Its invention came about researching inexpensive chemical

neg: Homologous temperature Homologous temperature Homologous temperature expresses the temperature of a material as a fraction of its melting point temperature using the Kelvin scale: formula_1 For example, the homologous temperature of lead at room temperature (25 °C) is approximately 0.50 (T = T/T = 298 K/601 K = 0.50). The homologous temperature of a substance is useful for determining the rate of steady state creep (diffusion dependent deformation). A higher homologous temperature results in an exponentially higher rate of diffusion dependent deformation. Additionally, for a given fixed homologous temperature, two materials with different melting points would have similar diffusion-dependent deformation behaviour. For

neg: 1,3-Difluoro-trisulfane-1,1-difluoride 1,3-Difluoro-trisulfane-1,1-difluoride 1,3-Difluoro-trisulfane-1,1-difluoride is an inorganic molecular substance consisting of sulfur in a low oxidation state with fluorine. The structural formula is SFSSF containing a chain of three sulfur atoms. At one end there are three fluorine atoms bound, and at the other one. The formula can also be written SF. It has a melting point of -62°C and a boiling point of 94°C. As a gas, it is unstable and breaks up to form SSF and SF. SFSSF is produced by the condensation of sulfur difluoride and an isomer of SSF. The reaction SF SSF + SF uses 6 kJ/mol.

neg: State of matter As heat is added to this substance it melts into a liquid at its melting point, boils into a gas at its boiling point, and if heated high enough would enter a plasma state in which the electrons are so energized that they leave their parent atoms. Forms of matter that are not composed of molecules and are organized by different forces can also be considered different states of matter. Superfluids (like Fermionic condensate) and the quark–gluon plasma are examples. In a chemical equation, the state of matter of the chemicals may be shown as (s) for solid, (l) for

neg: Allotropes of sulfur slow down formation of α-sulfur. It has a melting point variously quoted as 119.6 °C and 119.8 °C but as it decomposes to other forms at around this temperature the observed melting point can vary from this. The 119 °C melting point has been termed the "ideal melting point" and the typical lower value (114.5 °C) when decomposition occurs, the "natural melting point". This form, first prepared by F.W. Muthmann in 1890, is sometimes called "nacreous sulfur" or "mother of pearl sulfur" because of its appearance. It crystallises in pale yellow monoclinic needles. It contains puckered S rings like α-sulfur

neg: Hall–Héroult process be used instead, aluminium oxide has a melting point of 2072 °C so electrolysing it is impractical. In the Hall–Héroult process, alumina, AlO, is dissolved in molten synthetic cryolite, NaAlF, to lower its melting point for easier electrolysis. In the Hall–Héroult process the following simplified reactions take place at the carbon electrodes: Cathode: Anode: Overall: In reality much more CO is formed at the anode than CO: Pure cryolite has a melting point of 1009 ± 1°C. With a small percentage of alumina dissolved in it, its melting point drops to about 1000°C. Besides having a relatively low melting point,

neg: Melting point with high melting point". Carnelley based his rule on examination of 15,000 chemical compounds. For example, for three structural isomers with molecular formula CH the melting point increases in the series isopentane −160 °C (113 K) n-pentane −129.8 °C (143 K) and neopentane −16.4 °C (256.8 K). Likewise in xylenes and also dichlorobenzenes the melting point increases in the order meta, ortho and then para. Pyridine has a lower symmetry than benzene hence its lower melting point but the melting point again increases with diazine and triazines. Many cage-like compounds like adamantane and cubane with high symmetry have relatively high

neg: History of candle making It was a bluish-white wax, burned cleanly, and left no unpleasant odor, unlike tallow candles. A drawback to the substance was that early coal- and petroleum-derived paraffin waxes had a very low melting point. The introduction of stearin, discovered by Michel Eugène Chevreul, solved this problem. Stearin is hard and durable, with a convenient melting range of 54–72.5 °C (129.2–162.5 °F). By the end of the 19th century, most candles being manufactured consisted of paraffin and stearic acid. By the late 19th century, Price's Candles, based in London was the largest candle manufacturer in the world. The company traced its

neg: Cucujus clavipes inhibit ice nucleators to vary in low temperatures and may inhibit homogenous nucleation resulting in vitrification. Another study reported that if temperatures were held constant, then "C. clavipes" individuals with the highest water content had the highest probability of freezing, and individuals with the lowest water content had the lowest probability of freezing. AFPs decrease the temperature at which an ice crystal grows, defined as the hysteretic freezing point, by an average of 2–5 °C below the melting point in insects, which can be as much as 13 °C in "C. clavipes" in winter when the insect is dehydrated and

neg: Heptazine Berzelius first mentioned the heptazines in the 1830s when he discovered a polymeric substance after mercury thiocyanate ignition. Justus von Liebig named the polymer "melon". Much later in 1937 Linus Pauling showed by x-ray crystallography that heptazines are in fact fused triazines. The unsubstituted heptazine CNH was synthesized by Ramachandra S. Hosmane and others from the group of N. Leonard in the early 1980s. The structure of Berzelius's melon was confirmed only in 2001. The parent substance CNH is a yellow, weakly fluorescent solid with melting point over 300 °C. The compound is generally stable and soluble in organic solvents

neg: Pressure melting point Pressure melting point The pressure melting point is the temperature at which ice melts at a given pressure. The pressure melting point is nearly a constant 0 °C at pressures above the triple point at 611.7 Pa, where water can exist in only the solid or liquid phases, through atmospheric pressure (100 kPa) until about 10 MPa. With increasing pressure above 10 MPa, the pressure melting point decreases to a minimum of −21.9 °C at 209.9 MPa. Thereafter, the pressure melting point rises rapidly with pressure, passing back through 0 °C at 632.4 MPa. Glaciers are subject to geothermal heat

neg: Iridium platinum group metals, iridium is white, resembling platinum, but with a slight yellowish cast. Because of its hardness, brittleness, and very high melting point, solid iridium is difficult to machine, form, or work; thus powder metallurgy is commonly employed instead. It is the only metal to maintain good mechanical properties in air at temperatures above . It has the 10th highest boiling point among all elements and becomes a superconductor at temperatures below 0.14 K. Iridium's modulus of elasticity is the second-highest among the metals, only being surpassed by osmium. This, together with a high shear modulus and a very

neg: Thorium complex crystal structures and weakened metallic bonding. (The f-electron count for thorium is a non-integer due to a 5f–6d overlap.) Among the actinides up to californium, which can be studied in at least milligram quantities, thorium has the highest melting and boiling points and second-lowest density; only actinium is lighter. Thorium's boiling point of 4788 °C is the fifth-highest among all the elements with known boiling points. The properties of thorium vary widely depending on the degree of impurities in the sample. The major impurity is usually thorium dioxide (ThO); even the purest thorium specimens usually contain about a tenth

neg: Makiyakinabe to 35 cm and are often made of aluminium or cast iron. The best type is considered to be heavy copper coated with tin, although care has to be taken to avoid damage to the pan due to the low melting point of tin. A cheaper, Teflon coated pan is available in many stores. The depth of the pans is usually from 3 cm to 4 cm. Their weights are usually from 0.5 kg to 2.5 kg. There are three types of "makiyakinabe": Kantō-type, Kansai-type and Nagoya-type. The Kantō-type pans are squared. The Kansai-type pans are tall-and-thin rectangles. The Nagoya-type

neg: Furonazide Furonazide Furonazide is a crystalline tuberculostatic drug substance with a reported melting point of 199-201.5 °C. Furonazide was prepared in 1955 by Miyatake from isoniazid and 2-Acetylfuran by refluxing in ethanol, followed by filtration of the crystalline product. Furonazide has shown bacteriostatic action and is tuberculostatic at levels of 10-8 molar. The in vitro antibacterial activity of furonazide against Bacillus Calmette-Guerin was found to be essentially equal to that of isoniazid on an equimolar basis. In vivo studies in the guinea pig showed furonazide slightly more active than isoniazid as a tuberculostatic agent. The drug has relatively low toxicity. The

neg: Polybutylene flexible, resists impact well and has good elastic recovery. Isotactic polybutylene crystallizes in three different forms. Crystallization from solution yields form-III with the melting point of 106.5 °C. Cooling from the melt results in the form II which has melting point of 124 °C and density of 0.89 g/cm. At room temperature, it spontaneously converts into the form-I with the melting point of 135 °C and density of 0.95 g/cm. PB-1 generally resists chemicals such as detergents, oils, fats, acids, bases, alcohol, ketones, aliphatic hydrocarbons and hot polar solutions (including water). It shows lower resistance to aromatic and chlorinated hydrocarbons

neg: Thorium (sometimes called "thoria" in the industry), rather than the metal. This compound has a melting point of 3300 °C (6000 °F), the highest of all known oxides; only a few substances have higher melting points. This helps the compound remain solid in a flame, and it considerably increases the brightness of the flame; this is the main reason thorium is used in gas mantles. All substances emit energy (glow) at high temperatures, but the light emitted by thorium is nearly all in the visible spectrum, hence the brightness of thorium mantles. Energy, some of it in the form of visible

neg: Hassium relatively high melting points (Fe, 1538 °C; Ru, 2334 °C; Os, 3033 °C). Much like them, hassium is predicted to be a solid at room temperature, although the melting point of hassium has not been precisely calculated. Hassium should crystallize in the hexagonal close-packed structure (/ = 1.59), similarly to its lighter congener osmium. Pure metallic hassium is calculated to have a bulk modulus (resistance to uniform compression) comparable to that of diamond (442 GPa). Hassium is expected to have a bulk density of 40.7 g/cm, the highest of any of the 118 known elements and nearly twice the density

neg: Rhenium Rhenium Rhenium is a chemical element with symbol Re and atomic number 75. It is a silvery-gray, heavy, third-row transition metal in group 7 of the periodic table. With an estimated average concentration of 1 part per billion (ppb), rhenium is one of the rarest elements in the Earth's crust. Rhenium has the third-highest melting point and second-highest boiling point of any element at 5903 K. Rhenium resembles manganese and technetium chemically and is mainly obtained as a by-product of the extraction and refinement of molybdenum and copper ores. Rhenium shows in its compounds a wide variety of oxidation states

neg: Red-short carbon steel and brittle. This is due to the sulfur forming iron sulfide/iron mixtures in the grain boundaries of the metal which have a lower melting point than the steel. When the steel is heated up and worked, the mechanical energy added to the workpiece increases the temperature further. The iron sulfide (FeS) or iron/iron sulfide alloy (which has an even lower melting point) begins to melt, and the steel starts to separate at the grain boundaries. Steelmakers add manganese (Mn) to the steel when it is produced, to form manganese sulfide (MnS). Manganese sulfide inclusions have a higher melting point and

neg: Melting-point depression Melting-point depression The melting temperature of a bulk material is not dependent on its size. However, as the dimensions of a material decrease towards the atomic scale, the melting temperature scales with the material dimensions. The decrease in melting temperature can be on the order of tens to hundreds of degrees for metals with nanometer dimensions. Melting-point depression is most evident in nanowires, nanotubes and nanoparticles, which all melt at lower temperatures than bulk amounts of the same material. Changes in melting point occur because nanoscale materials have a much larger surface-to-volume ratio than bulk materials, drastically altering their thermodynamic

neg: Liquidus The crystal phase that crystallizes first on cooling a substance to its liquidus temperature is termed primary crystalline phase or primary phase. The composition range within which the primary phase remains constant is known as primary crystalline phase field. The liquidus temperature is important in the glass industry because crystallization can cause severe problems during the glass melting and forming processes, and it also may lead to product failure. The liquidus temperature can be contrasted to the solidus temperature. The solidus temperature quantifies the point at which a material completely solidifies (crystallizes). The liquidus and solidus temperatures do not necessarily

neg: Rheid structures may form. In some areas, such as the Gulf of Mexico, these structures often serve as traps for petroleum and natural gas. Rheid In geology, a rheid is a substance whose temperature is below the melting point and whose deformation by viscous flow during the time of observation is at least three orders of magnitude (1,000×) greater than the elastic deformation under the given conditions. A material is a rheid by virtue of the time of observation. The term, coined by S. Warren Carey in 1953, has the same Greek root as rheology, the science of viscoelasticity and nonlinear

neg: Benzanthrone and burning sensations on exposed skin, together with erythema, dermatitis, and skin pigmentation. Benzanthrone Benzanthrone (BZA) is an aromatic hydrocarbon derivate used as a dyestuff intermediate for anthraquinone-based dyes. It has the appearance of a light yellow to brown-green powder with melting point of 170 °C. It is insoluble in water and soluble in alcohol. It is a basic substance with fluorescent and luminescent properties. It can be used for photosensitization, and as a charge transport material. It is also used in pyrotechnics industry, mainly as a component of some older formulations of green and yellow colored smokes, often together

neg: Januarius increased by up to 28 grams during liquefaction. However, later measurements with a precision balance, performed over five years, failed to detect any variation. Various suggestions for the content's composition have been advanced, such as a material that is photosensitive, hygroscopic, or has a low melting point. However, these explanations run into technical difficulties, such as the variability of the phenomenon and its lack of correlation to ambient temperature. A recent hypothesis by Garlaschelli & al. is that the vial contains a thixotropic gel, In such a substance viscosity increases if left unstirred and decreases if stirred or moved. Researchers

neg: Citrus Red 2 Citrus Red 2 Citrus Red 2, Citrus Red No. 2, C.I. Solvent Red 80, or C.I. 12156 is an artificial dye. As a food dye, it has been permitted by the US Food and Drug Administration (FDA) since 1956 to color the skin of oranges. Citrus Red 2 is listed by the International Agency for Research on Cancer (IARC) as a group 2B carcinogen, a substance "possibly carcinogenic to humans". Citrus Red 2 is an orange to yellow solid or a dark red powder with a melting point of 156 °C. It is not soluble in water, but is readily

neg: Glucuronolactone Glucuronolactone Glucuronolactone is a naturally occurring substance that is an important structural component of nearly all connective tissues. Glucuronolactone is also found in many plant gums. Glucuronolactone is a white solid odorless compound, soluble in hot and cold water. Its melting point ranges from 176 to 178 °C. The compound can exist in a monocyclic aldehyde form or in a bicyclic hemiacetal (lactol) form. Glucuronolactone has received some notoriety due to an urban legend that it was a Vietnam War-era drug manufactured by the American government and since banned due to brain tumor-related deaths. However, the quoted "British Medical Journal"