Concentric cone

The first reported method for the direct phosphonomethylation of amino acids used phosphorous acid and formaldehyde (7). Typically, aqueous solutions of the amino acid, phosphorous acid, and concentrated (coned) hydrochloric acid were heated to reflux with excess aqueous formaldehyde or paraformaldehyde. The reaction proceeded equally well with either primary or secondary amines. However, with primary amines such as glycine, the yield of glyphosate was usually quite low, even at reduced temperature, and 1 1 1 stoichiometry. The resulting glyphosate acid (GLYH3) reacted faster than glycine, so the bis-phosphonomethyl adduct 2 always predominated. With excess phosphorous acid and formaldehyde, good isolated yields of this 2 1 adduct 2 have been obtained (8). 

If only one constituent were present in a sample, and there were no scattering effects, then there would be no possibility of interfering substances and one could likely find a wavelength at which Abs is proportional to concentration Cone. Under these conditions (adherence to Beer s Law), a simple equation can be created from a series of known samples by using a standard statistical tool (a least squares best fit) and defining an equation as follows ... 

Dilute solutions can be prepared from concentrated solutions. A volume of the concentrated solution is transferred to a fresh vessel and diluted to the desired final volume. The number of moles of reagent in V liters containing M moles per liter is the product M V = mol/L L, so we equate the number of moles in the concentrated (cone) and dilute (dil) solutions ... 

Figure 8.28 Schematic diagram showing (a) diffraction from a single crystal, (b) from four crystals at different orientations with respect to the incident beam and (c) from a polycrystalline powder giving rise to a pattern of concentric cones of diffraction, often presented as a one-dimensional plot of intensity vs diffraction angle (reproduced by permission of The Royal Society of Chemistry).

Figure 9 Scheme of dual-temperature multistage unit for bromine recovery from seawater. Storage tanks for bromine concentrates (cone. 1-3) are supplied with hicilities for cooling/heating the solution under treatment (T2>Ti). 

Melted snow and ice samples are nebulised at atmospheric pressure and transported into the plasma by an Ar flow. Ions formed in the high temperature plasma are extracted by a special interface with two concentric cones which allow ions to be accelerated and separated by a mass spectrometric analyser and finally detected by a secondary electron multiplier. 

Table V. Properties of Feed, Concentrate (Cone) and Permeate (Perm) Streams for Orange, Grapefruit and Lemon Juices Concentrated by Reverse Osmosis...

An instrument employed in the test method is either a cone-and-plate rheometer or a parallel-plate rheometer. In the first case, a flat, circular plate and a linearly concentric cone are rotated relative to each other. The cone is normally truncated so that there is no physical contact between the two. The fluid is in the space between the plate and cone. Either of the two members can be rotated or oscillated, and one measures the torque needed to keep the other member stationary. For both Newtonian... 

Plan To dilute a concentrated solution, we add only solvent, so the moles of solute are the same in both solutions. We know the volume (0.80 L) and molarity (0.15 M) of the dilute (dil) NaCl solution we need, so we find the moles of NaCl it contains and then find the volume of concentrated (cone 6.0 M) NaCl solution that contains the same number of moles. Then, we dilute this volume with solvent up to the final volume (see roadmap). Solution Finding moles of solute in dilute solution ... 

Total concentrations of detectable stable products (cyclohexanol and cyclohexanone) in the chromatogram of the sample unreduced with PPhj will be (C. + ACoiT" and (Cam ACo, ) " , respectively. Triphenylphosphine reduces the alkyl hydroperoxide to yield, quantitatively, cyclohexanol. So the concentrations of ol and one determined by GC in the sample treated with PPhj will be (C , + Cpnd) and (Co e)" , respectively. The real amount of ketone present in the reaction mixture may thus be determined by measuring the concentration (Cone) " of this product in the reduced sample. 

Figure 8.42 Schematic of diffraction from a powdered crystalline sample. The powdered sample generates the concentric cones of diffracted X-rays because of the random orientation of crystallites in the sample. The X-ray tube exciting the sample is not shown in this diagram. The cones of diffracted light intersect X-ray film curved to Ht the diameter of the Rowland circle. The result is a series of curved lines on the X-ray film.

Although the equilibrium concentration of ester in experiment 3 is greater than in experiment 2, we need take into account that the initial reaction mixture in experiment 3 contained some ester. To do this, we dehne the gain in ester concentration (cone.) ... 

Dissolving fert-butyl alcohol in concentrated (coned) aqueous hydrochloric acid soon results in the formation of fert-butyl chloride. The reaction is a substitution reaction ... 

It is necessary to prepare a calibration graph before results can be obtained by the following procedure known weight concentrations of the isomers from pure 2,4- and 2,6-TDI in the analytical range desired are prepared. The absorbance for each isomer is plotted versus concentration. The x-axis intercept (% 2,4- or % 2,6-isomer) and the -axis intercept (absorbance) that corresponds to the x-axis intercept are determined. The concentration (cone.) of each isomer is given by absorbance at 12 35 or 12 80 fim minus absorbance that corresponds to % isomer intercept on the x-axis divided by the units of absorbance per unit of isomer (slope) plus the % isomer intercept on the x-axis. The TDI isomer absorption is read or calculated from the cyclohexane baseline at 12 35 and 12 80 jum. 

Figure 2-9. Dimensions of concentric cone for externai pressure.

Fig. 13.5 Production of microbiai protein from feed DM in Feed into Miik (FiM). k iq, kc and kf are fractionai outfiow rates from the rumen for smaii particies, concentrates and forages. ATPy is the yieid of ATP from DM, and YATP is the efficiency of conversion of ATP into microbiai protein from soiubie and smaii particles (ssp), concentrates (cone.) and forage (forage).

The balance of incoming and outgoing sohds to maintain a steady volume fluidized bed is readily calculated from the volumetric concentrations of the incoming suspension and the fluidized bed. Sohds are removed by withdrawing excess fluidized bed material (e.g. floe blanket) over a slimy weir or into a concentrator cone at the surface of the fluidized bed (zone of separation into the clear liquid zone). In the examples calculated above ... 

From eq. (4.65), the concentration for concentration (cone.) polarization becomes... 

The gaps under cones are usually around half the pond depth. However, much smaller gaps have been used in vegetable oil refining (in a three-phase decanter). Uniquely in vegetable oil refining a double concentric cone has been used where the caustic soda wash is fed between the cones, rhe wash exits at the periphery of the cones under the surface of the oil. 

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