Separation reproducibility

Fig. 9 Illustration highlighting the possible importance of entropy in the charge separation process. Positive and negative polarons experience a strong coulombic attraction that may be offset by entropy to achieve charge separation. Reproduced with permission from [54]. Copyright 2010 American Chemical Society...

Fig. 5.3. Wayda-Dye greaseless vacuum line. This apparatus makes extensive use of metal bellows tubing and O-ring seals. Thus the reaction vessels, filters, and other items can be tilted and manipu lated like Schlenk ware, and high vacuum conditions can be achieved for the removal of atmospheric gases and for baking out residual moisture. Trap to-trap distillation of volatile solvents such as NH) or SO is readily accomplished with this apparatus. This version is not designed for the measurement of volatiles or trap-to-trap separation. (Reproduced from A.L. Way da and J. L. Dye, J. Chent. Educ. 62, 356 (1985) by permission of the copyright owner the Division of Chemical Education of the American Chemical Society.)...

Figure 11 Typical force-sampling time curve for the compression of a TB/C3 murine hybridoma. (AB) cell compression, (B) cell bursting, (C) cell debris compression, (DE) probes touching each other and (FG) two probes separated (reproduced from Thomas et al., 2000). Permitted by Springer.

Figure 3-29 Resonance Raman spectra of Fe(TPP-ds) co-condensed with l602 at 30K. (406.7 nm excitation), (a) 0.2 (b) 2.5 (c) 5.0 (d) 8.0 mW. These spectra are composites of four sections measured separately. (Reproduced with permission from Ref. 93. Copyright 1991 American Chemical Society.)...

Fig, 19. (a) Sketch of the channel-die apparatus used for the deformation experiment. Dimensions are in millimetres. The compression stamp is moved along the deformation direction D. The flow of the sample is constrained by the rigid walls of the die in the direction C, and free flow is possible in the direction F. (b) Stress (cr)-strain(e) diagram resulting from channel-die extrusion of bisphenol-A polycarbonate at 300 K and a strain rate of e = 0.01 s l. (c, d) Dipolar DECODER spectra of 13C-labelled bisphenol-A polycarbonate before and after deformation. The spectra exhibit a characteristic star-like ridge pattern. Each of three types of corners (C, D, F) in the pattern corresponds to vectors oriented along a particular direction in the channel-die used for the experiment, (e, f) The anisotropy caused by the deformation becomes readily visible in the difference spectrum (deformed minus undeformed). For clarity, the negative (f) and positive contours (e) have been drawn separately. (Reproduced from Utz et al. with permission.)... 

Figure. 5.2. Principle of operation of a centrifugal milk separator. Milk enters at the bottom of the unit and separates into heavier shim (dark grey) and lighter cream (pale grey) fractions which are recovered at the top of the separator (Reproduced with permission from Dairy Processing Handbook, Tetra Pak Processing Systems AB, Lund, Sweden, 1995).

It was shown previously that coal liquids from five major demonstration processes (Synthoil, HRI H-Coal, FMC-COED, PAMCO SRC, and Catalytic Inc. SRC) could be separated reproducibly, in high yields (94-99%) into five fractions by solvent fractionation (1,2). We now wish to report structural characterization parameters obtained for these materials by the use of proton nuclear magnetic resonance ( H NMR). 

Involving analyte-matrix separation Reproduced with permission of Springer-Verlag... 

Figure 8.12 Elution of a binary mixture with sorption effect (GC) and linear isotherms. Three successive chromatograms at the beginning of the separation. Reproduced with permission from L. Jacob and G. Guiochon, Chromatogr. Rev., 14 (1971) 77(Fig. 4).

Figure 18.26 Iterative scheme for optimizing displacement separations. Reproduced with permission from V. Natarajan, B. W. Bequette, S. M. Cramers, J. Chromatogr. A, 876 (2000) 51 (Fig. 1).

Figure 3. 22.7-NHz- C-NHR-spectruin of 1 1) at a monomar and b) after exposure to a Y ray dose of 30Hrad. Subsequent to y irradiation the crystals were disolved in 1 N aqueous KOO. The cadmium ions wore precipitated as CdS and separated. (Reproduced with permission from Ref. 10, Copyright 1981, Huthig und Mepf Verlag, Basel)...

Figure 12 Horizontal air separator. (Reproduced with permission from Ref. 12.)...

Fig. 8.23. Stress dependence measured at LHeT of the components of the C and D lines of Ga in germanium for F//<100>. The solid curves are the results of the second-order regression fit. The indications L and // correspond to ETF and E//F, respectively. The ground-state splitting is given directly by the D3 — D or D4 — D2 separation. Reproduced with permission from [143]. Copyright 1988, with permission from Elsevier...

Figure 3.1 Schematic of a modular HPLC instrument. A modular system allows users to adapt the Installation according to the applications to he carried out. The vertical assembly of the different modules affords an economy of space. Here the chromatograph, model HP 1200, comprises an auto-sampler that allows continuous operation and a thermostatically-controlled column to improve the reproducibility of the separations. (Reproduced courtesy of Agilent Technologies).

Fig. 3.2. System for double-column chromatography with intermediate trapping and re-injection, suitable also for direct injection of aqueous solutions. 1, carrier gas 2, pressure regulator 3, flow controller 4, vent for back-flushing S, injection port for heart-cut and back-flushing 6, precolumn (packed) 7, injection port for aqueous solutions 8, control flame ionization detector for pre-separation 9, vent for cutting 10. leak for make-up gas 11, trap 12, outlet of splitter 13, glass capillary column 14, flame ionization detector for main separation. Reproduced from [35].

Fig. 5.14 Continuous segmented assembly with liquid-liquid extractor for the determination of various amines by ion-pair formation. AC, mixing coils EC, extraction coils PS, phase separator. (Reproduced from [32] with permission of Springer Verlag).

Figure 17.1. Generalized mechanical loss (tan 5) and modulus-temperature behavior for various types of polymer blends. Case 1 (dashed-dotted line), miscible Case 2 (dashed line), partially miscible Case 3 (dotted line), microheterogenous Case 4 (solid line) phase separated. Reproduced with permission from O. Olabisi, L. M. Robeson, and M. T. Shaw, Polymer-Polymer Miscibility , Academic Press, New York, 1979.

Figure 11.102. Schematic representation of the dispersion process the polymer matrix is sheared and transported, whereby the agglomerates will be first distributed and destroyed, followed by dispersion (adsorption of a mono-molecular layer of matrix polymer onto the particle surface), and later phase separation. [Reproduced fiom ref 37 with kind permission of Elsevier.]...

Figure 9.31. The 2D diffusion-ordered (DOSY) spectrum of a mixture of glucose, adenosine 5 -triphosphate (ATP) and sodium dodecyl sulphate (SDS) micelles in D2O demonstrating die potential for mixture separation (reproduced with permission from [52], Copyright 1993, American Chemical Society).

Figure 2 Column switching flow diagram (A) preconcentration and (B) desorption and chromatographic separation. Reproduced with permission from O Keefe, Residue Analysis In Food, p. 78 (2000) Taylor and Francis.

Figure 1 Two-dimensional electrophoresis using a tube gel for isoelectric focusing and a slab gel for SDS-PAGE. The proteins are separated in the first dimension on the basis of charge and in the second dimension on the basis of molecular mass. The circles represent proteins, with shading to indicate protein pi values and diameters representing molecular mass. The clotted line shows the direction of separation. (Reproduced with permission from Twyman RM (2004) Principles of Proteomics. Abington, UK Bios/Gatland Publishers.)...

PITC (phenylisothiocyanate) UV 254 mn 1 pmol 15-27 min precolumn Salt interference, requires refrigeration, excess reagent removed under vacuum Ease of use, flexibility, good separation, reproducibility enhanced with automation... 

Wu et al. described the design of injection valves and separation reproducibility, and the use of a carbon dioxide-enhanced slurry packing method on the capillary scale for the separation of some benzodiazepines, herbicides, and various pharmaceutical compounds [43,50]. Tolley et al. modified a commercially available HPLC system to operate at 17,500 psi and used 22 cm long capillaries packed with 1.5 pm... 

Fig. 4. Source in which the excitation regions and ionization regions are separated. (Reproduced with permission of Collections of Czechoslovak Chemical Communications.)...

Figure 12.16 Schematic (a) and photograph (b) of phase separator. Reproduced by permission of the Royal Society of Chemistry [50].

F) electrolyte outlet (G) carbon-supported Pt electrocatalysts and (H) fiberglass separator. (Reproduced with permission from Ref. [27], Copyright by 2001 Electrochemical Society.)... 

It is apparent that it is not easy to obtain such separations reproducibly, and the separation of the first two isomers, in particular, is rarely easy. There is little to confuse the analysis in commercial CLA samples in which only Cjg fatty acids are present. However, when CLA is fed in nutritional experiments, other fatty acids may be present in tissues and confuse the picture. The important cis,trans- somexs usually elute in a region of the chromatogram that is free of other fatty acids. On the other hand, 21 0 or 20 2 fatty acids may occur naturally, and they elute in the same part of the chro-... 

Fig. 2 2D-separated local field spectrum of the liquid crystal EBBA obtained using the DAPT pulse sequence. The aliphatic and the aromatic parts of the spectra are shown separately. (Reproduced with permission from J. Phys. Chem. A. 2008, 112, 11159.)... 

Figure 13 Tapping-mode AFM height image of an etched PI-h-PFS organic organometallic diblock copolymer film. The dots result from block copolymer phase separation. (Reproduced with permission from Ref. 69, 2000 ACS.)...

Figure 3 Calculation of the effect of the chamber saturation on the separation. (Reproduced from Ref. 40, with permission.)...

Figure 8.2. Some commonly employed liquid membranes for metal ions separations. (Reproduced with permission from Mohapatra et al., 2003).

Potential energy diagram vs separation distance between two atoms. Note the various energies relative to the zero of energy at infinite separation. Reproduced from P.A. Rock, Chemical Thermodynamics, Copyright University Science Books, Mill Valley, CA used with permission. 

Figure6.20 Permselectivity of polymeric membranes for O2/N2 separation (reproduced from Robeson, L. M., Burgoyne, W. R, Langsam, M., Savoca, A. C. and Tien, C. R, Polym. (1994) 35, p. 4970 with permission from Elsevier)...

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