Volume reproducibility

The 10 volumes in the Series on characterization of particular materials classes include volumes on silicon processir, metals and alloys, catalytic materials, integrated circuit packaging, etc. Characterization is approached from the materials user s point of view. Thus, in general, the format is based on properties, processing steps, materials classification, etc., rather than on a technique. The emphasis of all volumes is on surfaces, interfaces, and thin films, but the emphasis varies depending on the relative importance of these areas for the materials class concerned. Appendixes in each volume reproduce the relevant one-page summaries from the Encyclopedia and provide longer summaries for any techniques referred to that are not covered in the Encyclopedia. 

Capillary electrophoresis offers several useful methods for (i) fast, highly efficient separations of ionic species (ii) fast separations of macromolecules (biopolymers) and (iii) development of small volume separations-based sensors. The very low-solvent flow (l-10nL min-1) CE technique, which is capable of providing exceptional separation efficiencies, places great demands on injection, detection and the other processes involved. The total volume of the capillaries typically used in CE is a few microlitres. CE instrumentation must deliver nL volumes reproducibly every time. The peak width of an analyte obtained from an electropherogram depends not only on the bandwidth of the analyte in the capillary but also on the migration rate of the analyte. 

Figure 19 Free volume plot for co(polyether)polyurethane membranes at 37°C for model drugs. D is the diffusion coefficient in cm2/sec, and H is the hydration expressed as (wet volume — dry volume)/wet volume. (Reproduced with permission from Ref. 59.)...

After equilibration, the sample is applied to a GF/G filter under reduced pressure. The filter is dried under vacuum such that the sample equilibrates with the filter hydration volume. Reproducible sample application to the central part of the filter is facilitated by the use of a special adapter. 

Figure 3.4—HPLC injection valve and assorted loops. Rear view of the valve showing six entries/exits and a series of loops with different volumes (reproduced by permission of Rheodyne Inc.).

Simple fractional distillation processes for purification of metalorganics can be employed to remove some of these impurities, but this is a very inefficient approach. A dramatic improvement in the yield of many high-purity metal alkyl compounds resulted from the development of the adduct-purification scheme for the purification of metal alkyls, which was commercially developed by A. C. Jones and coworkers. This process uses the strong tendency of many metal alkyls to form stable adduct compounds with other reactants, thus making a difficult problem that is encountered in the epitaxial growth arena into an useful advantage in the synthetic arena. Actual synthetic and purification routes employed in the manufacture of metal alkyls are proprietary. It is a challenge to develop an optimized synthetic process that has the required purity, efficiency, volume, reproducibility, and yield. 

Figure 4. Flux difference per particle per unit volume. Reproduced with permission from Ref. 10. Copyright 1980 Hemisphere Publishing.

FIGURE 7-7. Rate of gradient change defined by percent composition change per unit volume. (Reproduced from reference 1 with permission.)... 

The pressure gauge used in this experiment should be a direct-reading gauge with a relatively small and constant internal volume. Reproducibility is more important than absolute accuracy since relative measurements are made on air (the standard gas used for calibration) and the other gases. The critical feature is that the same initial P and final P inlet pressures are used in all runs. Thus, one can use capacitance, reluctance, or strain-gauge manometers (see p. 596-597). The latter manometers are the least expensive and are adequate if models with the best resolution are chosen. 

Fig. 8.17 AC conductivity versus frequency for a variety of carbon-black composites O crosslinked EBA with 8.3% acetylene black (AC), thermoplastic EBA with 11.3% AC, + thermoplastic EB with 14.5% AC, EBA particulate composite with 9.1% AC, EBA particulate composite with 10.7% AC, O blended PE with 9.2% AC, blended PE with 11.1% AC, A EPDM with 15.2% furnace black (FB), EPDM with 21.1% FB and EPDM with 26.3% FB (all percentages are by volume). Reproduced with permission of the Institute of Physics from Jager et al. (2001).

Figure 2. Chemical heterogeneity of the second kind in which polymers of different composition may coelute because of similar hydrodynamic volumes. (Reproduced from reference 5. Copyright 1986 American Chemical Society.)...

Figure 12.16 Adsorption isotherms and displacement chromatogram for 3,4-dihydroxyphenyl, 2-hydroxyphenyl, and 4-hydroxyphenyl acetic acids. (Left) Adsorption isotherms measured by frontal analysis on a 250 x4.6 mm column packed with 10 tm Partisil ODS-2 from 0.1 M phosphate buffer, pH 2.12 at 25°C. The soUd Unes are a least-squares fit of the data points to the Langmuir isotherm. (Right) Displacement chromatogram, carrier 0.1 M phosphate buffer, pH 2.12 displacer n-butanol at 0.97 M. Flow rate 0.05 mL/min at 25°C. Feed 1.5 mL of 30, 35, and 45 mg of 3,4 dihydroxy-, 4-, and 2-hydroxyphenylacetic acids, respectively. Fraction size, 0.15 mL. Fraction 40 marks 12 mL of eluent volume. Reproduced with permission from Cs. Horvath, A. Nahum and J.H. Frenz, J. Chroniatogr. 218 (1981) 365 (Figs. 6 and 7).

Fig. 2. Two-dimensional illustration of the geometric definition of the pore size distribution [25]. Point Z may be overlapped by all three circles of differing radii, whereas point Y is accessible only to the two smaller circles and point X is excluded from all but the smallest circle. The geometric pore size distribution is obtained by determining the size of the largest circle that can overlap each point in the pore volume. (Reproduced with permission from S. Ramalingam, D. Maroudas. and E. S. Aydil. Interactions of SiH radicals with silicon surfaces An atomic-scale simulation study. Journal of Applied Physics, 1998 84 3895-3911. Copyright 1998, American Institute of Physics.)...

Schematic representation of cartilage proteoglycan. The monomers, consisting of glycosaminoglycan chains linked to a core protein by covalent linkage, extend laterally at intervals from opposite sides of a very long filament of hyaluronate. The interaction between the core protein and hyaluronate is noncovalent and is aided by the link protein. The entire structure is highly hydrated and occupies a large volume. [Reproduced with permission from W. J. Lennarz, The Biochemistry of Glycoproteins and Proteoglycans, Plenum Press, New York, 1980].

Figure 14. IL3 concentration curves, small and large volume flux rates. Key 1, small volume 2, large volume. (Reproduced with permission from Ref. 4. Copyright 1984, American Society for Microbiology.)...

Figure 10. Deposition as a function of particle size for 15 respirations per minute, 750 cm3 tidal volume. Reproduced with permission from Task Group on Lung Dynamics (1966). Deposition and retention models for internal dosimetry of the human respiratory tract. Health Physics, 12, 173-207. Lippincott, Williams Wilkins...

To minimize the time taken to shim, we have adopted a weekly routine on an ideal standard sample, and users are supplied an updated optimal shim set upon which to start their experiments. Users are strongly encouraged to use moderate to high quality NMR tubes with exactly 600 uL of sample volume (reproducing the volume used in the standard samples) and to centre the NMR tube in the spinner carefully in relation to the receiver coils. Users are often able to interactively shim on the resulting lineshape requiring only slight corrections to the Z, Z2, Xi, and Yi shims. 

Figure 28.3 Interaction between previous pregnancy, smoking and low iodine intake. The association between tobacco smoking, parity and thyroid volume in the DanThyr population study, inoluding 3712 women. A significant statistical interaction was found for tobaoco smoking on the association between parity and thyroid volume. Reproduced from Knudsen et al., (2002a) with permission.

Figure 2.18 Literature data for vapor pressure for linear ( ), branched (A), and cycloalkanes ( ) as a function of molar volume. [Reproduced with permission from E. M. J. Verbruggen, J. L. M. Hermens, and J. Tolls, J. Phys. Chem. Ref. Data 29, 1435 (2000). Copyright 2000, American Chemical Society.]...

FIGURE 20.13 Examples of multiple emulsions formed in microfluidic systems (a) multiple shells-multiple cores configurations of monodisperse triple emulsions made with cascaded microcapillary devices results. (Reproduced with permission from Utada, A.S. et al.. Bull. MRS, 32(09), 702, 2007.), (b) composite emulsion formed by droplets of different composition and different volumes. (Reproduced with permission from Hashimoto, M. et al.. Small, 3(10), 1792, 2007.), and (c) examples of anisotropic particles formed by either polymerization (spheres and disks, rods) of droplets of monomer or thermal setting of droplets. (Reproduced with permission from Xu, S. et al., Angew. Chem. Int. Ed. Engl, 44(5), 724, 2005.)... 

Figure 3 Schematic diagram of apparatus for the determination of S from the pressure change on mixing gases at constant volume (Reproduced by permission from Rev. Sci. Instr., 1967, 38, 184)...

FIGURE 45.18 Results of four SEC fractionation experiments at different collection volumes. Polydispersity index of MALDI spectra of a copolymer sample denoted as M30 versus collection volumes. Reproduced from Montaudo et al. [69], copyright 2002 with permission. 

Standard mixtures are run on the HPLC system for evaluation of the separation volume, reproducibility and accuracy of the system. The c(Hiqx)sition of the standard mixture depends on the compound class under study. The amounts injected on the HPLC column are from 100 pg (organochlorines) to 1000 ng (hydrocarbons) each in 200pL of solvent (hexane). The solvent volumes required to elute selected groups of organic contaminants are summarized in Table 20-1. The solvent flow rate is 0.5mL/min. The eluates are collected in fractions of 0.5 mL. Each fraction is analysed by GC-ECD or GC-FID (flame ionization detection). Recoveries are from 90 to 100 %. 

Table 2.2 Correspondence principle parameters for the standard ionic partial molar volume (Reproduced from Geochimica et Cosmochimica Acta, Calculation of the thermodynamic and transport properties of aqueous species at high pressures and temperatures with permission from Elsevier)...

Figure 9.17 Field emission scanning electron microscope images of the bulk material at low (a) and high (b) magnification (c) water droplets exhibit spherical shape on the surface of the bulk material (d) mirror-like phenomenon can be observed on the bulk material submerged in water and (e) optical image and contact angle profile of the water droplet placed on the abraded bulk material. Bottom schematic illustration of a bulk material which can still sustain its superhydrophobicity after mechanical abrasion because of the low surface energy microstructures extending throughout its volume. Reproduced from [87,88] with permission of The Royal Society of Chemistry.

Figure F.3.2. Thermal variation of the kT V) term deduced from fitting procedure for three Fe/Al Oj samples with different average particle volumes. (Reproduced with permission from Ref. 35.)...

Figure 5.17 MALDI-ToF mass spectra of low molar mass fractions, 46,48, 50 collected during the SEC analysis of PET-e-caprolactone copolyester PET/CL (50/50)-2 (see Eigure 5.14). The two distributions correspond to linear macromolecules (lower masses) and cyclic macromolecules (higher masses) eluted at the same elution volume. Reproduced with permission from D. Tillier, H. Lefebvre, M. Tessier, J-C. Blais and A. Fradet, Macromolecular Chemistry and Physics, 2004, 205, 581. 2004, Wiley [49]...

Figure 7.2 Schematic representation of FBMRs for hydrogen production (a) bubbling fluidization regime (b) turbulent fluidization regime (c) fast fluidization regime. U = superficial gas velocity [7 = minimum bubbling velocity U =velocity of transition from bubbling to turbulent fluidization regime U =velocity of transition from turbulent to fast fluidization regime/significant entrainment ROG = reactor off-gas V=reactor volume. Reproduced from [6]. With permission from Elsevier.

Despite the inaccuracies regarding the quantitative determination of the specific volume the X-ray measurement of the speeifie volume reproduces the cooling rate dependent crystallization in a good manner as well as the pressure dependeney (Fig. 8). The temperature... 

---