Diamond classification

Table 9.3 Morphology of diamond Classification by Dana and Orlov...

A wide variety of materials have been classified with the TrtboClassifier with positive results. These include separation of natural from synthetic diamonds, classification of electroluminescent powder, removal of dust from dolomite, removal of irregular shapes from bronze cut wire, removal of Irregular shapes from granules of hard alloys, size classification of calcium carbonate, fly ash, copper particles etc. 

The classification of amorphous carbon films according to carbon bond type and hydrogen content can be represented in a triangular diagram, Fig. 6 [e.g., 70]. The comers at the base of the triangle correspond to graphite (100% sp carbon) and diamond (100% sp carbon). The apex represents 100% H, but the upper limit for formation of solid films is defined by the tie line between the compositions of polyethene, -(CH2) -, and polyethyne, -(CH) -. 

Nitrogen forms binary compounds with almost all elements of the periodic table and for many elements several stoichiometries are observed, e.g. MnN, Mn Ns, Mn3N2, MniN, Mn4N and Mn tN (9.2 < jc < 25.3). Nitrides are frequently classified into 4 groups salt-like , covalent, diamond-like and metallic (or interstitial ). The remarks on p. 64 concerning the limitations of such classifications are relevant here. The two main methods of preparation are by direct reaction of the metal with Ni or NH3 (often at high temperatures) and the thermal decomposition of metal amides, e.g. ... 

Steel Tooth Bit Selection 783. Diamond Bits 789. lADC Fixed Cutter Bit Classification System 801. Downhole Tools 812. Shock Absorbers 813. Jars. Underreamers 819. Stabilizers 823. 

The resultant four-character diamond bit classification code was formally presented to the lADC Drilling Technology Committee at the 1986 SPE/IADC Drilling Conference. It was subsequently approved by the lADC Board of Directors and designated to take effect concurrent with the 1987 SPE/IADC Drilling Conference. A description of the 1987 lADC Fixed Cutter Bit Classification Standard follows [54]. 

The four-character bit code is entered on an lADC-API Daily Drilling Report Form as shown in Figure 4-157. The space requirements are consistent with the four-character lADC roller bit classification code. The two codes are readily distinguished from one another by the convention that diamond bit codes begin with a letter, while roller bit codes begin with a number. 

A distinction between a solid and liquid is often made in terms of the presence of a crystalline or noncrystalline state. Crystals have definite lines of cleavage and an orderly geometric structure. Thus, diamond is crystalline and solid, while glass is not. The hardness of the substance does not determine the physical state. Soft crystals such as sodium metal, naphthalene, and ice are solid while supercooled glycerine or supercooled quartz are not crystalline and are better considered to be supercooled liquids. Intermediate between the solid and liquid are liquid crystals, which have orderly structures in one or two dimensions,4 but not all three. These demonstrate that science is never as simple as we try to make it through our classification schemes. We will see that thermodynamics handles such exceptions with ease. 

Explosive chemicals tend to be governed by separate legislation, e.g., in the UK, The Classification and Labelling of Explosives Regulations 1983. These require the HSE to classify any explosive before it may be supplied. Under the scheme, explosives are labelled according to a classification based on hazard division (Table 12.7), and on compatibility (Table 12.8), which takes into account their sensitivity, explosivity and chemical nature. Labels are diamond shaped the top half is reserved for the pictograph and division number, the bottom half shows the hazard code and the classification number. Figure 12.1 shows the label for Class 1, Division 1.1, 1.2 or 1.3 explosive. 

To prevent interchange of fittings between cylinders of combustible and non-combustible gases, the valve outlets are screwed left-hand and right-hand thread, respectively (Table 9.2). Primary identification is by means of labelling with the name and chemical formula on the shoulder of the cylinder. Secondary identification is by use of ground colours on the cylinder body. Unless specified in Table 9.2, gas and gas mixtures shall be identified by a colour classification indicating gas properties in accordance with the risk diamond on the cylinder label e.g. 

Many attempts at classifying solvent extraction systems have been made. Thus Diamond and Tuck [20] have described a classification of the solutes that can be separated by solvent extraction. 

Abstract Chronological studies of kimberlite-host rocks in the diamondiferous Buffalo Head Hills kimberlite field of north-central Alberta facilitate new interpretation of the nature, timing and sequence of kimberlite eruptions in northern Alberta. Three different emplacement episodes are recognized in association with volcanic and intrusive activity Late Cretaceous ( 88-81 Ma) Smoky Group equivalent intra- and extra-crater facies, Late Cretaceous and Paleocene ( 81 and 64 Ma) intrusion of sills or dykes, and Paleocene ( 60 Ma) Paskapoo Formation equivalent intra-crater facies. These specific periods of magmatism correspond to characteristic intra-field features such as spatial distribution, rock classification and diamond content. 

PfitTonai Fire Protection Association Classification indicated by number in a diamond, thus Unclassified by circle,... 

The classification and naming by Dana [9], [lO] and Orlov [11] of diamond forms... 

Although Dana [9], [10] and Orlov [11] classified diamond crystals broadly into two types, single and polycrystalline, we can also construct a classification (given in Table 9.4) based on the preceding analysis. By this classification we are able to correlate the morphology of diamonds with their growth conditions and growth histories. 

A.H. Deutchman and R.J. Partyka (Beam Alloy Corporation observe, "Characterization and classification of thin diamond films depend both on advanced surface-analysis techniques capable of analyzing elemental composition and microstructure (morphology and crystallinity), and on measurement of macroscopic mechanical, electrical, optical and thermal properties. Because diamond films are very thin (I to 2 micrometers or less) and grain and crystal sizes are very small, scanning electron microscopy... 

As for hydrides, borides, and carbides, different types of nitrides are possible depending on the type of metallic element. The classifications of nitrides are similarly referred to as ionic (salt-like), covalent, and interstitial. However, it should be noted that there is a transition of bond types. Within the covalent classification, nitrides are known that have a diamond or graphite structure. Principally, these are the boron nitrides that were discussed in Chapter 8. 

In the second place, the enzyme can make distinctions between isomers. In fact, nowhere is the selection ability of enzymes so manifest as in the ability to distinguish between isomeric structures. The various possibilities for a given number of atoms may be examined systematically. Thus, we can imagine the enzyme confronted with two materially identical molecules, making yes/no decisions in accordance with a defined classification chart. The enzyme asks Can the two molecules be superposed Arrows from the left sides of the diamonds indicate a yes answer from the right sides the arrows represent no (see Scheme 1). The possibility of superposition is... 

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