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Mulling Agent
Mulling is the process of grinding up a sample into fine powder through mortar and pestle that is dispersed in a paraffin for infrared spectroscopy. Sample preparation Using a nonporous ceramic mortar and pestle, a small quantity of the solid sample is ground up until the sample is exceedingly fine and has a glassy appearance. A drop of the mulling agent is added to the ground solid in the mortar. The mixture is further ground up until a uniform paste with the consistency of toothpaste is acquired. The resulting paste is transferred to a salt plate (sodium chloride) with a small flat spatula. The disks are gently pressed together, leaving the sample ready for analysis. Mulling agents There are a variety of mineral oil Mineral oil is any of various colorless, odorless, light mixtures of higher alkanes from a mineral source, particularly a distillate of petroleum, as distinct from usually edible vegetable oils. The name 'mineral oil' by itself is imprecise ...s used as mull ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mortar And Pestle
Mortar and pestle is a set of two simple tools used from the Stone Age to the present day to prepare ingredients or substances by crushing and grinding them into a fine paste or powder in the kitchen, laboratory, and pharmacy. The ''mortar'' () is characteristically a bowl, typically made of hard wood, metal, ceramic, or hard stone such as granite. The ''pestle'' (, also ) is a blunt, club-shaped object. The substance to be ground, which may be wet or dry, is placed in the mortar where the pestle is pounded, pressed, and rotated into the substance until the desired texture is achieved. Mortars and pestles have been used in cooking since prehistory; today they are typically associated with the profession of pharmacy due to their historical use in preparing medicines. They are used in chemistry settings for pulverizing small amounts of chemicals; in arts and cosmetics for pulverizing pigments, binders, and other substances; in ceramics for making grog; in masonry and in othe ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mineral Oil
Mineral oil is any of various colorless, odorless, light mixtures of higher alkanes from a mineral source, particularly a distillate of petroleum, as distinct from usually edible vegetable oils. The name 'mineral oil' by itself is imprecise, having been used for many specific oils over the past few centuries. Other names, similarly imprecise, include 'white oil', 'paraffin oil', ' liquid paraffin' (a highly refined medical grade), (Latin), and 'liquid petroleum'. Most often, mineral oil is a liquid by-product of refining crude oil to make gasoline and other petroleum products. This type of mineral oil is a transparent, colorless oil, composed mainly of alkanes and cycloalkanes, related to petroleum jelly. It has a density of around . Nomenclature Some of the imprecision in the definition of the names used for mineral oil (such as 'white oil') reflects usage by consumers and merchants who did not know, and usually had no need of knowing, the oil's precise chemical mak ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Infrared Spectroscopy
Infrared spectroscopy (IR spectroscopy or vibrational spectroscopy) is the measurement of the interaction of infrared radiation with matter by absorption, emission, or reflection. It is used to study and identify chemical substances or functional groups in solid, liquid, or gaseous forms. It can be used to characterize new materials or identify and verify known and unknown samples. The method or technique of infrared spectroscopy is conducted with an instrument called an infrared spectrometer (or spectrophotometer) which produces an infrared spectrum. An IR spectrum can be visualized in a graph of infrared light absorbance (or transmittance) on the vertical axis vs. frequency, wavenumber or wavelength on the horizontal axis. Typical units of wavenumber used in IR spectra are reciprocal centimeters, with the symbol cm−1. Units of IR wavelength are commonly given in micrometers (formerly called "microns"), symbol μm, which are related to the wavenumber in a reciprocal way. A ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sodium Chloride
Sodium chloride , commonly known as salt (although sea salt also contains other chemical salts), is an ionic compound with the chemical formula NaCl, representing a 1:1 ratio of sodium and chloride ions. With molar masses of 22.99 and 35.45 g/mol respectively, 100 g of NaCl contains 39.34 g Na and 60.66 g Cl. Sodium chloride is the salt most responsible for the salinity of seawater and of the extracellular fluid of many multicellular organisms. In its edible form, salt (also known as '' table salt'') is commonly used as a condiment and food preservative. Large quantities of sodium chloride are used in many industrial processes, and it is a major source of sodium and chlorine compounds used as feedstocks for further chemical syntheses. Another major application of sodium chloride is de-icing of roadways in sub-freezing weather. Uses In addition to the familiar domestic uses of salt, more dominant applications of the approximately 250 million tonnes per year product ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mineral Oil
Mineral oil is any of various colorless, odorless, light mixtures of higher alkanes from a mineral source, particularly a distillate of petroleum, as distinct from usually edible vegetable oils. The name 'mineral oil' by itself is imprecise, having been used for many specific oils over the past few centuries. Other names, similarly imprecise, include 'white oil', 'paraffin oil', ' liquid paraffin' (a highly refined medical grade), (Latin), and 'liquid petroleum'. Most often, mineral oil is a liquid by-product of refining crude oil to make gasoline and other petroleum products. This type of mineral oil is a transparent, colorless oil, composed mainly of alkanes and cycloalkanes, related to petroleum jelly. It has a density of around . Nomenclature Some of the imprecision in the definition of the names used for mineral oil (such as 'white oil') reflects usage by consumers and merchants who did not know, and usually had no need of knowing, the oil's precise chemical mak ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Nujol
Nujol is a brand of mineral oil by Plough Inc., cas number 8012-95-1, and density 0.838 g/mL at 25 °C, used in infrared spectroscopy. It is a heavy paraffin oil so it is chemically inert and has a relatively uncomplicated IR spectrum, with major peaks between 2950-2800, 1465-1450, and 1380–1300 cm−1. The empirical formula of Nujol is hard to determine exactly because it is a mixture but it is essentially the alkane formula where ''n'' is very large. To obtain an IR spectrum of a solid, a sample is combined with Nujol in a mortar and pestle or some other device to make a mull (a very thick suspension), and is usually sandwiched between potassium- or sodium chloride Sodium chloride , commonly known as salt (although sea salt also contains other chemical salts), is an ionic compound with the chemical formula NaCl, representing a 1:1 ratio of sodium and chloride ions. With molar masses of 22.99 and 35. ... plates before being placed in the spectrometer. For ver ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Reciprocal Length
Reciprocal length or inverse length is a quantity or measurement used in several branches of science and mathematics. As the reciprocal of length, common units used for this measurement include the reciprocal metre or inverse metre (symbol: m−1), the reciprocal centimetre or inverse centimetre (symbol: cm−1). Quantities measured in reciprocal length include: * absorption coefficient or attenuation coefficient, in materials science *curvature of a line, in mathematics *gain, in laser physics * magnitude of vectors in reciprocal space, in crystallography *more generally any spatial frequency e.g. in cycles per unit length * optical power of a lens, in optics * rotational constant of a rigid rotor, in quantum mechanics *wavenumber, or magnitude of a wavevector, in spectroscopy *density of a linear feature in hydrology and other fields; see kilometre per square kilometre In optics, the dioptre is a unit equivalent to reciprocal metre. Measure of energy In some b ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mid-infrared
Infrared (IR), sometimes called infrared light, is electromagnetic radiation (EMR) with wavelengths longer than those of visible light. It is therefore invisible to the human eye. IR is generally understood to encompass wavelengths from around 1 millimeter (300 GHz) to the nominal red edge of the visible spectrum, around 700 nanometers (430 THz). Longer IR wavelengths (30 μm-100 μm) are sometimes included as part of the terahertz radiation range. Almost all black-body radiation from objects near room temperature is at infrared wavelengths. As a form of electromagnetic radiation, IR propagates energy and momentum, exerts radiation pressure, and has properties corresponding to both those of a wave and of a particle, the photon. It was long known that fires emit invisible heat; in 1681 the pioneering experimenter Edme Mariotte showed that glass, though transparent to sunlight, obstructed radiant heat. In 1800 the astronomer Sir William Herschel discove ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
