The present application relates generally to moving die rheometers, and more particularly to moving die rheometers that employ a variable eccentric cam. In one aspect, the eccentricity produced by the cam may be adjusted using shims of different thickness to alter the position of the post on the cam.

The present application relates generally rheometers. In one aspect, misalignment of the air cylinder with respect to the cross-head is accommodated using a flexible coupling between the air cylinder and the cross-head so as to prevent binding and stuttering of the machine due to misalignment.

A method for evaluating phase stability of an electrode mixture slurry, including the steps of: (S1) introducing the electrode mixture slurry to a rheometer; (S2) applying a first shear rate to the electrode mixture slurry; (S3) applying a second shear rate after applying the first shear rate to the electrode mixture slurry, wherein the second shear rate is higher than the first shear rate; (S4) applying a third shear rate after applying the second shear rate to the electrode mixture slurry, wherein the third shear rate is lower than the second shear rate; and (S5) comparing the shear viscosity at the first shear rate with the shear viscosity at the third shear rate. An apparatus for evaluating phase stability of the electrode mixture slurry is also provided.

Sag propensity of a fluid can be determined by applying an oscillatory strain at an amplitude in excess of a linear region and below a yield strain of the drilling fluid. This may include use of medium amplitude oscillatory shear (MAOS), from which an elastic modulus of the fluid is determined. The elastic modulus may be determined over time, from which a time to reach maximum elastic modulus can be determined. The time to reach maximum elastic modulus is then converted or correlated to a drilling fluid sag propensity for the drilling fluid either in absolute terms or in relation to base or comparison fluids. Such an evaluation can be performed using a torsional resonance device in which the oscillatory strain is controllable so as to be maintained relatively constant during the measurement.

The present invention provides an apparatus for use in viscoelastic analysis, for example in coagulation testing of sample liquids, such as blood and/or its elements. In the apparatus for use in viscoelastic analysis, the rotating means are provided below the cup, pin and cup receiving element. The present invention further provides capacitive detection means and temperature control devices, which may be used in the apparatus for use in viscoelastic analysis. The present invention further provides a method of performing viscoelastic analysis, e.g. coagulation analysis, on a sample using the devices and apparatuses.

A method for determining the density of an at least flowable, in particular liquid, specimen with a rheometer, in particular a rotational rheometer, includes providing the rheometer with a first measurement component for receiving the at least flowable, in particular liquid, specimen, and a second measurement component with a known volume to be immersed into the specimen. The first and second measurement components are movable relative to one another. The perpendicular force between the two measurement components is measured after the immersion of the second measurement component into the specimen. The measured perpendicular force corresponds to the buoyancy force acting between the specimen and the second measurement component. The density of the specimen is calculated based on Archimedes' principle by reference to the known volume of the second measurement component and the measured perpendicular force. A rheometer for carrying out the method is also provided.

Techniques for determining rheological properties of a fluid include actuating a resonator disposed in a volume that contains a fluid sample to operate the resonator in the fluid sample at a predetermined actuation scheme; measuring at least one characteristic of the resonator based on the operation of the resonator in the fluid sample; comparing the at least one measured characteristic to a rheological model that associates characteristics of the fluid sample to one or more rheological properties; and based on the comparison, determining one or more rheological properties of the fluid sample.

The invention relates to a wave-emitting device comprising an electromechanical actuator stimulated by a signal generator that allows it to generate torsional waves with a higher amplitude, and to an ultrasonic transducer comprising said device. The use of said devices allows the reconstruction of the structural characteristics of the materials subject to the waves generated by the emitter device.

A method for evaluating the rheological properties of at least one gel, consisting in determining the extent of the plastic domain in stress ζ.sub.c−ζ.sub.p, and in strain γ.sub.c−γ.sub.p, the determination being carried out according to the steps: subjecting at least one sample of at least one gel to oscillating mechanical stresses at a fixed frequency, determining and plotting curves of the elastic modulus G′ and the viscous modulus G″ as a function of the strain and stress, determining ζ.sub.c and ζ.sub.p at the point of intersection X.sub.c of the curves of G′ and G″ under stress and strain, determining ζ.sub.p and γ.sub.p by fixing an arbitrary value of G′ (G′x) that is defined as the entry value into the plastic domain, and calculating ζ.sub.c−ζ.sub.p and γ.sub.c−γ.sub.p.

The invention discloses a device for viscosity or viscoelasticity measurement comprising: a horizontal rotatable cylinder-shaped section for receiving a liquid whose viscosity or viscoelasticity is to be measured, and a torque meter for measuring the torque from said liquid while in rotation. It also discloses a method of measuring viscosity or viscoelasticity of a liquid comprising the following steps: placing a liquid into a horizontal rotatable cylinder-shaped section, said liquid partially filling said structure; rotating said structure at a speed such that a quasi-cylindrical inner free surface of the liquid is obtained; determining the torque from said liquid when rotating said partially filled structure and calculating the viscosity or viscoelasticity of the liquid from the torque determined in the previous step.