Middle diameter

Middle Diameter The smallest possible distance between two points on the particle, between which the projection of the particle can pa.ss... 

Figure 4. Selected measures of. size on a single particle (modilied from Muller, 1967). See Table II for delinitions. Df . Feret s diameter Dm Marlin s diameter, Dk Krumbein s diameter Dmd Middle diameter Dl Long diameter.

During the optical coat work stress examination method the upper plate of the head of some of the bolts was covered with an optical coat work (Fig. 4). On the head of some other bolts strain gauges were stuck which measured the plain biaxial stress state in the middle of the top surface of the head of the bolt (3.5 x 3 mm). The magnetic probe detected average stresses up to 0.1 mm depth in an area of 14 mm diameter in the middle of the head of the bolt. 

The curve is symmetric from the middle of the slot. Hence the length of the defect is determined by the position of its edges at (x2+x3)/2 and -(x2+x3)/2 in the scanning direction of the probe. Of course this result is only true if we can distinguish the 5 zones on the curve. For other relative dimensions, for example a slot smaller than the probe (outer diameter), a curve like in set 1 is obtained, where the zones are confused. 

Figure Bl.22.1. Reflection-absorption IR spectra (RAIRS) from palladium flat surfaces in the presence of a 1 X 10 Torr 1 1 NO CO mixture at 200 K. Data are shown here for tluee different surfaces, namely, for Pd (100) (bottom) and Pd(l 11) (middle) single crystals and for palladium particles (about 500 A m diameter) deposited on a 100 A diick Si02 film grown on top of a Mo(l 10) single crystal. These experiments illustrate how RAIRS titration experiments can be used for the identification of specific surface sites in supported catalysts. On Pd(lOO) CO and NO each adsorbs on twofold sites, as indicated by their stretching bands at about 1970 and 1670 cm, respectively. On Pd(l 11), on the other hand, the main IR peaks are seen around 1745 for NO (on-top adsorption) and about 1915 for CO (tlueefold coordination). Using those two spectra as references, the data from the supported Pd system can be analysed to obtain estimates of the relative fractions of (100) and (111) planes exposed in the metal particles [26].

Figure C2.6.2. CSLM image of near hard-sphere silica particles of diameter d = 1050 nm witli a fluorescent core of diameter 400 nm, showing fee stacking (top), hep stacking (bottom middle) and amoriDhous areas (image size 16.3 pm X 16.3 pm, courtesy of Professor A van Blaaderen)...

The mixture to be separated is dissolved in a suitable solvent and spotted on to a pencilled line at the bottom of the t.l.c. plate, ca. i o-i 5 cm. from the end. A suitable dropping tube may he made by drawing out the middle of a m.p. tube with a micro-burner and breaking the tube in the middle. The dropper is filled by capillary action and is discharged when the liquid at the tip drops on to the untouched absorbent surface the spot should be 2 5 mm. in diameter. 

It will be convenient to deal first with the distribution aspect of the problem. One of the clearest ways in which to represent the distribution of sizes is by means of a histogram. Suppose that the diameters of SOO small spherical particles, forming a random sample of a powder, have been measured and that they range from 2-7 to 5-3 pm. Let the range be divided into thirteen class intervals 2-7 to 2-9 pm, 2-9 to 3-1 pm, etc., and the number of particles within each class noted (Table 1.5). A histogram may then be drawn in which the number of particles with diameters within any given range is plotted as if they all had the diameter of the middle of the... 

Most of the AHoy 600 outer diameter tube corrosion has occurred in the region of the upper tubesheet near the open lane, ie, an untubed lane across the middle of the steam generator (16,17). The steam carries entrained droplets of water through the open lane to the upper tubesheet region where the droplets dry out and concentrate the chemicals. Long tube inserts have been used to sleeve tubes in this region where wall defects have been detected. 

The whirlpool was introduced in the early 1960s (Fig. 8). The tank is cylindrical with a fiat bottom its diameter in ratio to height is usually 1 1.4. The hot wort is led tangentially into the tank, approximately in the middle of its side. 

Figure 18.3 Protein crystals contain large channels and holes filled with solvent molecules, as shown in this diagram of the molecular packing in crystals of the enzyme glycolate oxidase. The subunits (colored disks) form octamers of molecular weight around 300 kDa, with a hole in the middle of each of about 15 A diameter. Between the molecules there are channels (white) of around 70 A diameter through the crystal. (Courtesy of Ylva Lindqvist, who determined the structure of this enzyme to 2.0 A resolution in the laboratory of Carl Branden, Uppsala.)...

Bromine (128 g., 0.80 mole) is added dropwise to the well-stirred mixture over a period of 40 minutes (Note 4). After all the bromine has been added, the molten mixture is stirred at 80-85° on a steam bath for 1 hour, or until it solidifies if that happens first (Note 5). The complex is added in portions to a well-stirred mixture of 1.3 1. of cracked ice and 100 ml. of concentrated hydrochloric acid in a 2-1. beaker (Note 6). Part of the cold aqueous layer is added to the reaction flask to decompose whatever part of the reaction mixture remains there, and the resulting mixture is added to the beaker. The dark oil that settles out is extracted from the mixture with four 150-ml. portions of ether. The extracts are combined, washed consecutively with 100 ml. of water and 100 ml. of 5% aqueous sodium bicarbonate solution, dried with anhydrous sodium sulfate, and transferred to a short-necked distillation flask. The ether is removed by distillation at atmospheric pressure, and crude 3-bromo-acetophenone is stripped from a few grams of heavy dark residue by distillation at reduced pressure. The colorless distillate is carefully fractionated in a column 20 cm. long and 1.5 cm. in diameter that is filled with Carborundum or Heli-Pak filling. 4 hc combined middle fractions of constant refractive index are taken as 3-l)romoaccto])lu iu)nc weight, 94 -100 g. (70-75%) l).p. 75 76°/0.5 mm. tif 1.57,38 1.5742 m.]). 7 8° (Notes 7 and 8). 

Figure 8.19 illustrates another example of the versatility of multidimensional OPLC, namely the use of different stationary phases and multiple development ("D) modes in combination with circular and anticircular development and both off-line and on-line detection (37). Two different stationary phases are used in this configuration. The lower plate is square (e.g. 20 cm X 20 cm), while the upper plate (grey in Figure 8.19) is circular with a diameter of, e.g. 10 cm. The sample must be applied on-line to the middle of the upper plate. In the OPLC chamber the plates are covered with a Teflon sheet and pressed together under an overpressure of 5 MPa. As the mobile phase transporting a particular compound reaches the edge of the first plate it must-because of the forced-flow technique-flow over to the second (lower) stationary phase, which is of lower polarity. 

The capillary tube method initially involves packing a powdered sample into a glass capillary tube of uniform diameter and length, carefully sealed at one end so that it forms a rounded tube of uniform thickness. The tube is then attached to a standardized thermometer so that the end of the tube reaches the middle of the thermometer reservoir bulb. This assembly is then inserted into a vessel contg a suitable liq which is uniformly heated so that the temp rises at a rate of about 1° per minute. Ref 1 discusses in detail equipment design and thermometer calibration. It should be noted that this technique is the method most widely used by organic chemists... 

This design was closely followed in the experimental model and in the later instruments. The experimental model (October, 1940) had as test body a dumbbell of two thin-walled glass spheres 4 mm. in diameter sealed to a glass rod 6 mm. long. A silica fiber 8 fi in diameter was stretched between the prongs of a silica fork, and the glass dumbbell was cemented with shellac to the middle of the fiber, perpendicular to it. A plane glass mirror 2 mm. square was also cemented near the middle of the fiber. The suspension was balanced... 

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