Local and Average Diffusion of Nanosolutes in Agarose Gel: The Effect of the Gel/Solution Interface Structure

Langmuir ◽  
2007 ◽  
Vol 23 (4) ◽  
pp. 2083-2090 ◽  
Author(s):  
Jérôme Labille ◽  
Nicolas Fatin-Rouge ◽  
Jacques Buffle
2002 ◽  
Vol 20 (5) ◽  
pp. 511-522 ◽  
Author(s):  
S. Chibowski ◽  
M. Wiśniewska ◽  
M. Paszkiewicz

The influence of the molecular weight of polyelectrolytes on their adsorption and on the structure of the adsorbed layers at the manganese oxide(IV)–polymer solution interface was determined. Polyacrylic acid (PAA) and polyacrylamide (PAM) were applied as ionic polymers. An explanation was proposed for the observed changes in surface charge and zeta potential of the solid in the presence of these polymers. The thickness of the adsorption layer of PAA and PAM was determined and the free energies of adsorption of these polymers on the MnO2 surface were calculated from the zeta potential measurements.


Author(s):  
C. B. Carter ◽  
J. Rose ◽  
D. G. Ast

The hot-pressing technique which has been successfully used to manufacture twist boundaries in silicon has now been used to form tilt boundaries in this material. In the present study, weak-beam imaging, lattice-fringe imaging and electron diffraction techniques have been combined to identify different features of the interface structure. The weak-beam technique gives an overall picture of the geometry of the boundary and in particular allows steps in the plane of the boundary which are normal to the dislocation lines to be identified. It also allows pockets of amorphous SiO2 remaining in the interface to be recognized. The lattice-fringe imaging technique allows the boundary plane parallel to the dislocation to be identified. Finally the electron diffraction technique allows the periodic structure of the boundary to be evaluated over a large area - this is particularly valuable when the dislocations are closely spaced - and can also provide information on the structural width of the interface.


Author(s):  
M.J. Witcomb ◽  
U. Dahmen ◽  
K.H. Westmacott

Cu-Cr age-hardening alloys are of interest as a model system for the investigation of fcc/bcc interface structures. Several past studies have investigated the morphology and interface structure of Cr precipitates in a Cu matrix (1-3) and good success has been achieved in understanding the crystallography and strain contrast of small needle-shaped precipitates. The present study investigates the effect of small amounts of phosphorous on the precipitation behavior of Cu-Cr alloys.The same Cu-0.3% Cr alloy as was used in earlier work was rolled to a thickness of 150 μm, solution treated in vacuum at 1050°C for 1h followed by quenching and annealing for various times at 820 and 863°C.Two laths and their corresponding diffraction patterns in an alloy aged 2h at 820°C are shown in correct relative orientation in Fig. 1. To within the limit of accuracy of the diffraction patterns the orientation relationship was that of Kurdjumov-Sachs (KS), i.e. parallel close-packed planes and directions.


Author(s):  
Brigid R. Heywood ◽  
S. Champ

Recent work on the crystallisation of inorganic crystals under compressed monomolecular surfactant films has shown that two dimensional templates can be used to promote the oriented nucleation of solids. When a suitable long alkyl chain surfactant is cast on the crystallisation media a monodispersied population of crystals forms exclusively at the monolayer/solution interface. Each crystal is aligned with a specific crystallographic axis perpendicular to the plane of the monolayer suggesting that nucleation is facilitated by recognition events between the nascent inorganic solid and the organic template.For example, monolayers of the long alkyl chain surfactant, stearic acid will promote the oriented nucleation of the calcium carbonate polymorph, calcite, on the (100) face, whereas compressed monolayers of n-eicosyl sulphate will induce calcite nucleation on the (001) face, (Figure 1 & 2). An extensive program of research has confirmed the general principle that molecular recognition events at the interface (including electrostatic interactions, geometric homology, stereochemical complementarity) can be used to promote the crystal engineering process.


1988 ◽  
Vol 60 (02) ◽  
pp. 133-136 ◽  
Author(s):  
R Schneppenheim ◽  
H Plendl ◽  
U Budde

SummaryA luminescence assay was adapted for detection of von Willebrand factor multimers subsequent to SDS-agarose gel electrophoresis and electroblotting onto nitrocellulose. The method is as fast as chromogenic detection methods and appears to be as sensitive as autoradiography without the disadvantages of the latter.


1972 ◽  
Vol 27 (03) ◽  
pp. 610-618 ◽  
Author(s):  
H Graeff ◽  
R von Hugo

SummaryThe observation of fibrinogen derivatives with a molecular weight higher than the parent molecule in human cases of DIC initiated the present methodological study. These derivatives were identified by the following methods : 2.5 M β-alanine precipitation of the plasma samples, PAA gel electrophoresis, intra gel immunoprecipitation and agarose gel chromatography. In the plasma of a patient with severe eclampsia and laboratory signs of DIC two derivatives with a molecular weight higher than that of fibrinogen were identified according to their relative electrophoretic mobilities: 0.18 and 0.28 × 10−5 cm2/V × sec (fibrinogen: 0.43 × 10−5 cm2/V × sec). Electrophoretic studies in the presence of 5 M urea indicated that the 0.28 derivative is a complex probably formed by fibrinogen and a fibrin monomer.


1970 ◽  
Vol 23 (02) ◽  
pp. 202-210 ◽  
Author(s):  
R Bishop ◽  
H Ekert ◽  
G Gilchrist ◽  
E Shanbrom ◽  
L Fekete

SummaryA new fibrin plate technic for evaluating components of the fibrinolytic system has been developed. It provides quick, accurate, and easily interpreted results for the fibrinolytic profile. The standardized human plasminogen-free fibrin plates can be produced in bulk and stored for prolonged periods of time. A test specimen placed in a well punched in the buffered agarose gel diffuses into the agar and lyses the fibrin clot, forming a clear reaction zone. The zone diameter is directly proportional to the log of the percent concentration of available fibrinolytic enzyme in the specimen. The plates may be used to quantitate total plasminogen, and estimate available plasmin and active plasmin. A good correlation between results obtained using these fibrin plates and caseinolytic methods was found. Performance and interpretation of tests of fibrinolysis done on these new fibrin plates indicate that it may be the most sensitive technic available for clinical laboratory work.


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