Mortar, diamond

Diamant-glanz, m. adamantine luster, -kitt, m. diamond cement. -mOrser, m, diamond mortar (small steel mortar), -pulver, n. diamond dust, -schwarz, n. diamond black, -spat, m. adamantine spar (corundum). -Stahl, m, very hard steel, tool steel, Diamido-. diamino-, diamido- (see Amido-), -benzol, n. diaminobenzene, -toluol, n. diaminotoluene. 

Preparation for X-ray Analysis. Lattice constants are calculated from patterns obtained on powder samples with a Norelco diffractometer using monochromatic radiation (AMR-202 Focusing Monochromator) from a high-intensity copper source. The crystals are powdered with a diamond mortar and pestle, and the powder passed through a 74-/ sieve. Accurate lattice constants are calculated from the x-ray data. 

Plattner s diamond mortar and pestle of hard tool steel. 

Plattner diamond mortar A device for crushing small amounts of brittle materials. 

Although silicon compounds have been used since the earliest times, the element was not obtainable until advances in technology came about. Minerals containing silicon include sand and silicates that are widely distributed (silicon constitutes approximately 23% of the earth s crust), and they have been used in making glass, pottery, and mortar for many centuries. In addition to these uses, silicon is now highly purified for use in integrated circuits (chips) and as an alloy known as Duriron that has many uses. Silicon has the diamond structure with a density of 2.3 g/cm3. 

G-17216, and in Victoria Land by John Mulligan, also on an NSF grant to the Bureau of Mines. Each sample was crushed by hand with a mortar and pestle to approximately 0.625 by 0.25 inch. A split of each crushed sample was embeaaed in epoxy resin, polished, examined microscopically, photographed, and then its reflectance was determined. Knoop indention hardnesses were also determined by using a 20-gram load on the diamond indenter. The indenter was kept in contact with the sample for 15 seconds. Additional splits of each sample were crushed to minus 60 mesh, dried at 100°C. for 24 horns, and their electrical resistivity was determined at 20,000 p.s.i. The sample locations, chemistry, petrography, reflectance, electrical resistivity, and hardness of the 36 Antarctic coal samples studied are included in Table I. 

B4C boron carbide has a melting point of 2450 °C and a hardness somewhere between those of SiC and diamond. This makes the material a suitable abrasive. It is used in heads of sand blasting equipment, in mortars and in armour plating. For the latter application a B4C plate is provided on both sides with a plastic which has been reinforced with glass fibre. This is done to reduce the risk of splintering. Boron carbide is also used as the raw material for many other boron compounds ... 

Boron forms a compound with carbon, B C. This substance, boron carbide, is the hardest substance known next to diamond, and it has found extensive use as an abrasive and for the manufacture of small mortars and pestles for grinding very hard substances. 

Face-centered cubic crystal lattice. Burns when heated with a hot enough flame (over 800, oxygen torch), df 3.513. rt 2 4173. Hardness — 10 (Mohs scale), Sp heat at 100°K 0.606 cal/g-atom/ K. Entropy at 298.I6 K 0,5684 cal/g-atom/ K. Band gap energy 6.7 ev. Dielectric constant 5.7. Electron mobility —1800 cm1/v-sec. Hole mobility 1200 cmz/v-sec. Can be pulverized in a steel mortar. Attacked by laboratory -type cleaning soln (potassi um dichromate + coned HiSO ), In the jewelry trade the unit of weight for diamonds is one carat — 200 mg. Ref Wall Street J. 164, no. 36, p 10 (Aug 19, 1964),... 

The separation of dentin and enamel is usually carried out mechanically by chipping the enamel in a mortar made of an inert material (Helsby, 1974 Retief et al, 1974) or by grinding with a diamond disc (Steinnes et al, 1974 Stack et al, 1977). A carbide steel... 

Experiments. The micro structure of the mortar beams is investigated with a Philips XL 30 FEG Scanning Electron Microscope (SEM). For the analysis in the secondary electrons (SE) mode, freshly broken surfaces are prepared. Polished surfaces are analyzed in the backscattered electrons (BSE) mode. The final polishing stage is carried out with a 1 pm diamond paste. In order to render the mortar surface conductive, samples are coated by evaporation with gold prior to the SEM investigation. 

We can also contrast Blue Nile, with its online retailing model for diamonds, with Zales, which sells diamond jewelry through retail outlets. Blue Nile has emphasized the variety of diamonds available from its website and the fact that its margins are significantly lower than its bricks-and-mortar competition. Customers, however, have to wait to get their jewelry and do not have any opportunity to touch and see it before purchase (Blue Nile does provide a 30-day return period, though). At Zales, in contrast, a customer can walk into the retail store, be helped by a salesperson, and leave immediately with a diamond ring. The amount of variety available at a Zales store, however, is limited. Whereas Blue Nile offers more than 90,000 stones on its site, a typical Zales store carries fewer than a thousand. 

Blue Nile is an online retailer of diamonds that has used responsive transportation with FedEx to ship diamonds to customers in the United States, Canada, and several countries in Europe and Asia. Given the high value of diamonds, Blue Nile offers free shipping for overnight delivery. Responsive shipping, however, allows Blue Nile to centralize its inventory of diamonds and eliminate the need for expensive storefronts. In spite of the high transportation costs. Blue Nile has very low costs compared with those of bricks-and-mortar retailers because of the low facility and inventory expenses. Blue Nile is thus able to offer significantly lower prices than its bricks-and-mortar competition. 

R.S. Barneyback and S. Diamond, Expression and analysis of pore fluids from hardened cement pastes and mortars , Cem. Conor. Res. 11,1981,279-285. 

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