Powders, definition

Indigenous peanut oil Katchung oil Peanut oil Pecan shell powder Definition Refined fixed oil obtained fiom seed kernels of one or more cultivated varieties of Arachs hypogaea Properties Colorless to pale yel. liq., nutty odor, bland taste sol. in benzene, ether, chloroform, CCI oils misc. with carbon disulfide si. sol. in alcohol insol. in alkalis dens. 0.916-0.922 solid, pt. -5 C iodine no. 84-100 sapon. no. 185-195 flash pt. 540 E ref. index 1.466-1.470... 

CAS 9010-66-6 EINECS/ELINCS 232-722-9 Synonyms Zein powder Definition Alcohol-sol. protein obtained from corn, Zea mays component of corn gluten Properties Wh. to yel. powd., odorless sol. in aq. alcohols, glycols, glycol ethers, furfuryl alcohol, tetrahydrofurfuryl alcohol, aq. alkaline sol ns. with... 

The sur ce FT-IR stey of a nanosize aluminum nitride powder definitely brought evidence of the specific chemical composition of its first atomic layer. The unavoidable contamination, mainly by atmospheric water, implies the presence of oxygen and hydrogen in this first layer. As a result, a comparison with the alumina sur ce appeared quite reasonable. Indeed, methanol and pyridine used as probe molecules showed the same behavior on both material sur ces. The acidity of the AIN sur ce was proven by the presence of two types of Al Lewis sites. However for AIN, a specific dissociative adsorption mechanism of acidic methanol could be possibly explained by the presence of weakly basic AI3N sites. Besides, the isotopic exchange... 

Synonyms Arachis hypogaea Arachis oil Earthnut oil Groundnut oil Indigenous peanut oil Katchung oil Peanut oil Pecan shell powder Definition Refned fixed oil obtained from seed kernels of one or more cultivated varieties of Arachis hypogaea... 

For tire purjDoses of tliis review, a nanocrystal is defined as a crystalline solid, witli feature sizes less tlian 50 nm, recovered as a purified powder from a chemical syntliesis and subsequently dissolved as isolated particles in an appropriate solvent. In many ways, tliis definition shares many features witli tliat of colloids , defined broadly as a particle tliat has some linear dimension between 1 and 1000 nm [1] tire study of nanocrystals may be drought of as a new kind of colloid science [2]. Much of die early work on colloidal metal and semiconductor particles stemmed from die photophysics and applications to electrochemistry. (See, for example, die excellent review by Henglein [3].) However, the definition of a colloid does not include any specification of die internal stmcture of die particle. Therein lies die cmcial distinction in nanocrystals, die interior crystalline stmcture is of overwhelming importance. Nanocrystals must tmly be little solids (figure C2.17.1), widi internal stmctures equivalent (or nearly equivalent) to drat of bulk materials. This is a necessary condition if size-dependent studies of nanometre-sized objects are to offer any insight into die behaviour of bulk solids. 

Suspend the crude hydrochloride in some water in a separating-funnel and add 20% sodium hydroxide solution until the mixture is definitely alkaline and the crude phenylhydrazine base floats as a deep red oil on the surface. Now extract the phenylhydrazine twice with benzene (using about 30 ml. of benzene on each occasion) and dry the united benzene extracts with powdered... 

To the cold acid chloride add 175 ml. of pure carbon disulphide, cool in ice, add 30 g, of powdered anhydrous aluminium chloride in one lot, and immediately attach a reflux condenser. When the evolution of hydrogen chloride ceases (about 5 minutes), slowly warm the mixture to the boiling point on a water bath. Reflux for 10 minutes with frequent shaking the reaction is then complete. Cool the reaction mixture to 0°, and decompose the aluminium complex by the cautious addition, with shaking, of 100 g. of crushed ice. Then add 25 ml. of concentrated hydrochloric acid, transfer to a 2 htre round-bottomed flask and steam distil, preferably in the apparatus, depicted in Fig. II, 41, 3 since the a-tetralone is only moderately volatile in steam. The carbon disulphide passes over first, then there is a definite break in the distillation, after whieh the a-tetralone distils completely in about 2 htres of distillate. 

Classically, aerosols are particles or droplets that range from about 0.15 to 5 p.m ia size and are suspended or dispersed ia a gaseous medium such as air. However, the term aerosol, as used ia this discussion, identifies a large number of products which are pressure-dispensed as a Hquid or semisohd stream, a mist, a fairly dry to wet spray, a powder, or even a foam. This definition of aerosol focuses on the container and the method of dispensiag, rather than on the form of the product. 

Consolidation. Metal powders are consoHdated by heat or by pressure followed by heat, or by heating during the appHcation of pressure (17). ConsoHdation produces a coherent mass of definitive size and shape for further working, heat treating, or use as is. 

Definitions of Terms Used in Powder Metallurgy, MPIF Standard 09, Metal Powder Industries Federation, Princeton, N.J., 1992. 

Standards and definitions for whole milk powder, partiy skimmed milk powder, and skimmed milk powder have been set by WHO. This standard apphes exclusively to dried milk products as defined, having a fat content of not mote than 40 mol %. 

The following definitions are particular to bulk powders handling. 

Exempt colorants are made up of a wide variety of organic and inorganic compounds representing the animal, vegetable, and mineral kingdoms. Some, like -carotene and 2inc oxide, are essentially pure factory-produced chemicals of definite and known composition. Others, including annatto extract, cochineal extract, caramel, and beet powder are mixtures obtained from natural sources and have somewhat indefinite compositions. 

The micas, as a class, are difficult to grind to a fine powder one exception is disintegrated schist, in which the mica occurs in minute flakes. For diy grinmng, hammer mills equipped with an air-transport system are generally used. Maintenance is often high. It has been established that the method of milling has a definite effect on the par-... 

At X-ray fluorescence analysis (XRF) of samples of the limited weight is perspective to prepare for specimens as polymeric films on a basis of methylcellulose [1]. By the example of definition of heavy metals in film specimens have studied dependence of intensity of X-ray radiation from their chemical compound, surface density (P ) and the size (D) particles of the powder introduced to polymer. Have theoretically established, that the basic source of an error of results XRF is dependence of intensity (F) analytical lines of determined elements from a specimen. Thus the best account of variations P provides a method of the internal standard at change P from 2 up to 6 mg/sm the coefficient of variation describing an error of definition Mo, Zn, Cu, Co, Fe and Mn in a method of the direct external standard, reaches 40 %, and at use of a method of the internal standard (an element of comparison Ga) value does not exceed 2,2 %. Experiment within the limits of a casual error (V changes from 2,9 up to 7,4 %) has confirmed theoretical conclusions. 

The definitions coarsely chopped to finely powdered , which formerly in the pharmacopoeias were given as mesh sizes, are mostly nowadays indicated without such a requirement in the DAB 10, V. 4.N6, only coarsely chopped (4000 to 2800 sieve), finely chopped (2000 sieve), and powdered (710 to 180 sieve) are distinguished. The wide particle-size ranges have rightly been criticized [1, 2], partly on the basis of extensive investigations. 

Perhaps the most definitive result to come from the early nickel-aluminia synthesis work was the thermal analysis investigation of Hammetter [88HO 88W01], which showed explicit data on substantial changes in the shockec-but-unreacted mixtures. Differential thermal analysis was carried out on th -starting powder compacts of both the mechanically mixed and composite powders. Shocked and unreacted powders were compared to provide direc evidence for substantial changes introduced by the shock process. 

For use in medicine, opium is dried, powdered and standardised to a definite content of morphine, which the British Pharmacopoeia 1932 places at 10 per cent, (limits 9-5 and 10-5), and the United States Pharma-copceia (XIII) at not less than 10 or more than 10-5 per cent. 

Para, Tube or Bamboo Curare. This variety was packed in sections of bamboo, but this almost traditional information needs modification since tube curare became a commercial article. It is now a viscous, solid or even powdered extract, exported in sealed tins. In view of the relationship established between bebeerine, curine, and tubocurarhie, the active alkaloid of this variety of curare, the suggestion was made, first by Spath, Leithe and Ladeck, and more definitely by King that its botanical source should be sought among the Brazilian Menispermaceae, and as shown later the search for the source of the d-tubocurarine found in this variety of curare has been narrowed down to Chondrodendron tomentosum, or possibly a closely related species liable to be confused with it. 

The definitive structural determination of the P -hydroxide is the powder neutron diffraction work of Greaves and Thomas on / - Ni(OD)2 [22], They did neutron... 

The deviations of Class I, here called absorption and enhancement effects, are known in the literature also as matrix effects, as self-absorption, and as interelement effects. The authors consider the most important objection to each of the last three names to be as. follows. To matrix effect the element sought (ncrt included in the matrix) contributes to the absorption effect for the sample in the same kind of way as any element (free or combined) in the matrix. To self-absorption the name makes no provision for enhancement effects. To interelement effects it fails to recognize that an absorption effect occurs even when only one element is present (Equation 7-4). The term matrix is useful but requires precise definition. What is the matrix when an internal standard is added, or when a powdered sample is dissolved ... 

Where definite loss of color by bleaching is noted, the content and container should be inspected to determine the cause. If correctable, such as a faulty gasket, broken container, etc, the gasket is changed or the powder is transferred to another container. A new strip of test paper is inserted and the proplnt replaced in storage with the container definitely marked to insure reinspection at the end of one year. 

Since the foregoing tests were carried out at -identical conditions of compn and temp, and in a standard test fixture, the burning times serve as a means of checking the relative fineness of thea powdered tungsten fuels. The rapid burning times indicate that both M-10 and M-20 are very fine. Also, the M-10 is definitely finer than M-20, as shown by the difference in burning times... 

The first definite production of plutonium metal was made in November, 1943 by Baumbach and coworkers (1958). Approximately 35 micrograms of PuFi in a small thoria crucible in a high vacuum was reacted with barium metal at 1400 C to yield plutonium metal. The metal was found to have a silvery lustre, a density of about 16 grams j>er cubic centimeter and it rapidly absorbed hydrogen at about 210 C to form a black powder subsequently identified as PUH3 (a proof that metal had been produced). 

Before proceeding further it is well to consider the term cement, for its definition can be the source of some confusion. Both the Oxford English Dictionary and Webster give two alternative definitions. One defines a cement as a paste, prepared by mixing a powder with water, that sets to a hard mass. In the other a cement is described as a bonding agent. These two definitions are quite different. The first leads to a classification of cements in terms of the setting process, while the second lays emphasis on a property. In this book the term cement follows the sense of the first of these definitions. 

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