The purpose of the present invention is to achieve an in-situ observation of structural change in a shear field of slurry, i.e. an evaluation of a rheology property of slurry containing raw materials of a ceramic as a fluid sample, together with an in-situ observation of internal structure of the fluid sample in an evaluation process, and a clarification of internal structural change. An observation of an internal structure of a fluid sample 1 in an evaluation process of a rheology property by a rheometer 10 is achieved by generating an optical coherence tomographic image by performing an optical coherence tomography by irradiating a light in infrared region from outside of the rheometer 10 to the fluid sample 1, by inclining an optical axis of light in infrared region irradiating the fluid sample 1 for a predetermined angle within an angular range of 1 to 10 degrees with respect to a normal direction of an observation surface 1A of the fluid sample 1 by the optical coherence tomography imaging device 20, together with an evaluation of a rheology property of the fluid sample 1 containing components different in a refractive index by the rheometer 10.

An extension assembly is connected or connectable, in terms of driving, to a double-motor rheometer. The double-motor rheometer includes first and second measuring motors controllable independently of each other, and provided for determining a torsional moment generated by the corresponding measuring motor. The extension assembly includes first and second sample holding parts for holding a first sample portion and a second sample portion of the sample. The first sample holding part is driveable by the first measuring motor in a rotational movement about a first axis, and the second sample holding part is driveable by the second measuring motor in a rotational movement about a second axis. The first axis is arranged so as to be parallel to and spaced apart from the second axis. The sample held in the first sample portion and in the second sample portion extends between the respective sample holding parts.

An in vitro method for diagnosing, stratifying, prognosing and/or monitoring a lung and/or respiratory disease, and for evaluating the effectiveness of a treatment of a lung and/or respiratory disease, can include the determination or the measurement of the value A.sub.nl of at least one rheological parameter on a sample of mucus A of a subject, in a non-linear zone of the deformation curve of the sample, and/or of the value A.sub.l of at least one rheological parameter on said sample, in a linear zone of the deformation curve of the sample, wherein the rheological parameter is selected from the elasticity modulus (G′), the viscosity modulus (G″), the complex modulus G*, the damping factor (tan δ), the complex modulus (G*), the critical deformation (γ.sub.c), the plastic deformation (γ.sub.p), the flow stress threshold (τ.sub.c), the plastic stress (τ.sub.p), and the elastic force (EF), the critical stress (σ.sub.c), and any combination thereof.

A rheometer and a method for measuring viscosity of a specimen include a motor-driven measuring shaft, a first measuring part fastened to the shaft, a second measuring part below the first measuring part, the measuring parts defining a measuring gap receiving the specimen and having a thickness set by the measuring parts. A heating or temperature-control unit below the second measuring part temperature-controls the second measuring part. The measuring parts rotate or rotate-oscillate relative to each other about an axis. A hood has an internal contour at the second measuring part and/or the heating or temperature-control unit. The internal contour surrounds and covers the first measuring part and the measuring gap and forms a measuring space. A duct near the temperature-control unit opens into the space, allowing the temperature-control unit to control a temperature of temperature-control medium in the duct.

A rheological system includes a sample chamber, a compressed air system configured to provide compressed air to pressurize the sample chamber, and a rotor configured for rheological measurement of a material with variable volume, the rotor including an elongated shaft extending to a measurement portion having a widened geometry relative to the elongated shaft. The rotor is dimensioned such that a compression ratio of at least 5 to 1 is achievable while maintaining material cover of the sample over the entirety of the measurement portion of the rotor, the compression ratio being defined by a decompressed volume of a sample when the sample chamber is not pressurized to a compressed volume of the sample when the sample chamber is pressurized. Methods of taking rheological measurements with such a rotor are also disclosed.

A method for determining a suitability of a lubricant to avoid false brinelling damage in a bearing includes providing a rheometer and the lubricant, performing a first conditioning of the rheometer, filling the rheometer with a first lubricant sample, and deforming the first lubricant sample to determine a first shear stress from a first shear deformation of the first lubricant sample at the first temperature, with reference to the first zero point. The method also includes performing a second conditioning of the rheometer, refilling the rheometer with a second lubricant sample, and deforming the second lubricant sample to determine a second shear stress from a second shear deformation of the second lubricant sample at the second temperature, with reference to the second zero point. The lubricant is classified as suitable or unsuitable for avoiding false brinelling damage as a function of the first shear stress and the second shear stress.

A method for determining a suitability of a lubricant to avoid false brinelling damage in a bearing includes providing a rheometer and the lubricant, performing a first conditioning of the rheometer, filling the rheometer with a first lubricant sample, and deforming the first lubricant sample to determine a first shear stress from a first shear deformation of the first lubricant sample at the first temperature, with reference to the first zero point. The method also includes performing a second conditioning of the rheometer, refilling the rheometer with a second lubricant sample, and deforming the second lubricant sample to determine a second shear stress from a second shear deformation of the second lubricant sample at the second temperature, with reference to the second zero point. The lubricant is classified as suitable or unsuitable for avoiding false brinelling damage as a function of the first shear stress and the second shear stress.

The invention provides a system for the preshearing based control of the flow and deformation behavior, i.e., the setting kinetics, and the time dependent shear viscosity, elasticity of aqueous cementitious suspensions that can be used for bone repair and regeneration. The dynamic cement microstructure is tailored to the demands of the surgical tasks (faster/slower setting) or additive manufacturing tasks (lower/higher viscosity) by application of various preshearing conditions. Since the relationships between the preshearing and pressurization conditions and the setting kinetics and the time dependent changes in elasticity and viscosity are complex, a priori characterization of viscoelastic properties using the advanced rheological characterization technique of small-amplitude oscillatory rheometry is needed to enable such tailoring. The preshearing system is intended to give control on the injectability and setting time of any calcium phosphate cement formulation to the surgeon during an orthopedic surgery where a batch of bone cement is processed. Other possible utilizations of the system include controlling the setting kinetics, shear viscosity and facilitating the resultant flow stability of cementitious ceramic suspensions processed in direct ink writing assemblies for additive manufacturing of cement constructs, in injection systems for oil wells, restoration and fracking.

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.

A bob for a viscometer in a portable rheology unit is provided. The bob may include a bob portion having a cylindrical portion and a first end portion, the cylindrical portion defining a first end of the bob. The bob may also include a plastic portion interfacing with an interior surface of the first end portion, wherein the plastic portion includes a conical area extending from a conical area first end to a conical area second end, and the conical second end is connected to an interior surface of the cylindrical portion. The bob may also include a sleeve portion connected to the plastic portion and a bob second end portion connected to the sleeve portion.