Abstract: A method of determining a relationship between a mutual diffusion co-efficient Dm and the concentration c of a solute within a solvent. The method comprises: obtaining a Taylorgram comprising a plurality of measurements of solute concentration c; and deriving from the Taylorgram a plurality of mutual diffusion coefficient values Dm corresponding with a plurality of different concentrations c of solute in the solvent.

Abstract: A method of estimating a parameter for fitting a multi-component Taylorgram model to Taylorgram data g(t) is disclosed. The data comprises a multi-component Taylorgram peak or front at t=tr. The method comprises: evaluating a value of an integration or differential of the data; determining the parameter, based on an analytical expression that includes the value of the integral or differential of the data, the parameter corresponding with a physical property of a sample from which the Taylorgram data was obtained.

Abstract: A particle characterization apparatus is disclosed comprising: a first light source; a second light source, a sample cell; a first detector and a second detector. The first light source is operable to illuminate a first region of a sample comprising dispersed particles within the sample cell with a first light beam along a first light beam axis so as to produce scattered light by interactions of the first light beam with the sample. The first detector is configured to detect the scattered light. The second light source is operable to illuminate a second region of the sample with a second light beam along a second light beam axis. The second detector is an imaging detector, configured to image the particles along an imaging axis using the second light beam. The first light beam axis is at an angle of at least 5 degrees to the second light beam axis.

Abstract: A particle characterization apparatus comprising: a light source for illuminating a sample with a light beam; a detector arranged to detect scattered light from the interaction of the light beam with the sample; and a focus tuneable lens arranged to collect the scattered light for the detector from a scattering volume and/or to direct the light beam into the sample.

Abstract: A particle characterization apparatus having first and second body parts, a light source, a sample cell and a detector. The light source illuminates dispersed particles within the sample cell with a light beam along an axis to produce scattered light. The sample cell has first and second walls. The walls have internal surfaces arranged to be in contact with the sample and an opposite external surface. The light beam passes through the external surface of the first wall, through the internal surface of the first wall, through the sample, through the internal surface of the second wall, and through the external surface of the second wall. The light source is fixed to the first body part, which engages with the first wall. The detector is fixed to the second body part, which engages with the second wall. The first and second body parts are separable to enable access to the internal surfaces of the walls for cleaning.

Abstract: A rheometer is disclosed that includes rheometry logic that is responsive to a material selection control, to an objective selection control, to material property storage, and to process parameter storage, and is operative to assist the user with a measurement using the rheometer. In another general aspect, a rheometer includes sample history storage operative to store a history that spans a plurality of different operations performed by the rheometer on a same sample.

Abstract: A high-throughput optical suspension characterization instrument is disclosed, which can include hydraulically separate and at least partially transparent sample containers. A selection mechanism is operative to selectively direct light from a light source (12) through different ones of the sample containers along an optical axis, and an off-axis scattering detector (38,24) is responsive to scattered light from the light source after it has interacted with a sample. Phase analysis light scattering is used to determine the electrophoretic mobility and zeta potential of samples. A second instrument is disclosed, wherein all sample containers are illuminated simultaneously. Transmitted light is collected by a camera. The electrophoretic mobility and hydrodynamic size of the samples may be determined.

Abstract: A fluid characterization measuring instrument comprises a sample vessel (14) for a bulk complex sample fluid having a capacity that is substantially larger than a domain size of the complex sample fluid and that is sufficiently large to cause bulk scattering effects to substantially exceed surface effects for the complex fluid sample, a coherent light source (12) positioned to illuminate the bulk complex sample fluid in the sample vessel and a first fibre (16) having a first end positioned to receive backscattered light from the sample after it has interacted with the sample. The first fibre is positioned close enough to an optical axis of the coherent light source and to the sample vessel to substantially decrease a contribution of multiply scattered light in the backscattered light.

Abstract: Rheometer, also usable for stress-strain-investigations, with at least one bearing (28; 35) having an adjustable stiffness in a direction normal to the bearing surfaces (19, 20, 21, 22, 23, 24, 26, 27). The instrument further includes a system (31, 32, 33, 34; 36, 37) for controlling a parameter for adjusting the stiffness of the at least one bearing (28; 35); a system (10) for determining a value of a quantity associated with a second force exerted between the rotor (8, 5, 6,7) and the stator (2) and opposing the force associated with the quantity to be determined; and a data processing system for correcting the determined value of the quantity associated with the second force by a bias value, obtained using a mapping having as a parameter a variable representative of the parameter for adjusting the stiffness.

Abstract: In one general aspect, an electrophoretic measurement method is disclosed that includes providing a vessel that holds a dispersant, providing a first electrode immersed in the dispersant, and providing a second electrode immersed in the dispersant. A sample is placed at a location within the dispersant between the first and second electrodes with the sample being separated from the electrodes, an alternating electric field is applied across the electrodes, and the sample is illuminated with temporally coherent light. A frequency shift is detected in light from the step of illuminating that has interacted with the sample during the step of applying an alternating electric field, and a property of the sample is derived based on results of the step of detecting.

Abstract: In one general aspect, a method of measuring characteristics of particles in a liquid sample is disclosed. The method includes suspending the liquid sample in a tube. The suspended liquid sample is illuminated along an illumination axis, and at least a portion of the light is detected along a first detection axis after it is scattered by the particles in the suspended liquid sample. The illumination axis and the detection axis are oriented at an angle with respect to each other.

Abstract: In one general aspect, a multi-sample liquid scattering measurement apparatus is disclosed. It includes a coherent light source having an optical output axis, with sample cells that each include a volume that intersects with the optical output axis. Detectors are each positioned to detect scattered light resulting from an interaction between light from the coherent light source and one of the cells. Light scattering analysis logic is responsive to the detectors and operative to determine a property of a liquid sample in each of the sample cells based on the detected scattered light.

Abstract: In one general aspect, a method of measuring characteristics of particles in a liquid sample disclosed. The method includes supporting the liquid sample by surface tension and illuminating the supported liquid sample along an illumination axis with spatially coherent light so as to cause the coherent light to be scattered across a scattering zone. At least a portion of the scattered light is detected along a first predetermined scattering detection axis after it is scattered by the particles in the supported liquid sample. The illumination axis and the detection axis are oriented at an angle with respect to each other that allows substantially all of the light scattered at that angle across the scattering zone to be detected.

Abstract: In one general aspect, an instrument for measuring characteristics of particles suspended in a fluid is disclosed. It includes a closed wall surface defining a fractionation channel having a input opening, an output opening, and a flow axis that spans downstream from the input opening for the channel to the output opening. A force application subsystem has a force application output oriented perpendicular to at least part of the flow axis of the fractionation channel. A particle characteristic measurement subsystem is located hydraulically downstream from at least a portion of the closed wall surface defining the fractionation channel, and includes a sensor positioned to sense a property of the suspended particles in the potential measurement subsystem as well as a signal output responsive to the sensor.

Abstract: In one general aspect, a spectroscopic apparatus is disclosed for investigating heterogeneity of a sample area. The apparatus includes an image acquisition system operative to acquire images of a plurality of sub-areas in the sample area and a sub-area selection interface operative to receive a selection designating one of the sub-areas for which an image has been obtained. A spectrometer has a field of view and is operative to acquire a spectrum of at least part of one of the sub-areas in its field of view, and a positioning mechanism is responsive to the sub-area selection interface and operative to position the field of view of the spectrometer relative to the sample area based on a received selection.

Abstract: An apparatus for providing a light beam for use in a diffraction instrument (1) includes a device (10; 17; 28) for generating a light beam; and means (12, 21; 24) for shaping the light beam generated by the device (10; 17; 28), dimensioned, in use, to determine the beam shape, and including: an aperture (21; 25) and means (13; 24) for rejecting spatial frequency components above a certain range in the light beam. The apparatus further includes a spatial low-pass filter (14; 15; 26; 27) arranged to filter a beam provided by the beam shaping means.

Abstract: In one general aspect, a spectroscopic apparatus is disclosed for investigating heterogeneity of a sample area. The apparatus includes an image acquisition system operative to acquire images of a plurality of sub-areas in the sample area and a sub-area selection interface operative to receive a selection designating one of the sub-areas for which an image has been obtained. A spectrometer has a field of view and is operative to acquire a spectrum of at least part of one of the sub-areas in its field of view, and a positioning mechanism is responsive to the sub-area selection interface and operative to position the field of view of the spectrometer relative to the sample area based on a received selection.

Abstract: In one general aspect, a particle characterization instrument is disclosed that includes a first spatially coherent light source with a beam output aligned with an optical axis. A focusing optic is positioned along the optical axis after the coherent light source, and a sample cell is positioned along the optical axis after the focusing optic. The instrument also includes a diverging optic positioned along the optical axis after the sample cell, and a detector positioned outside of the optical axis to receive scattered light within a first range of scattering angles from the diverging optic. In another general aspect, an instrument can direct at least a portion of a first beam and at least a portion of a second beam along a same optical axis and a can receive scattered light from the sample cell resulting from interaction between the sample and either the first beam or the second beam.

Abstract: In one general aspect, a spectroscopic method for monitoring heterogeneity of a sample is disclosed. In this method, sampled spectroscopic measurements are acquired over a range of different micro locations in a macro-sample of the sample. This step is repeated for micro-locations in further macro-samples of the sample, and a statistical measure of chemical heterogeneity is derived from the acquisitions. In another general aspect, differently sized samples are acquired, and a statistical measure of chemical heterogeneity is derived from these acquisitions.