Abstract: Rheological measurement systems for use with systems including pressurized polymer melts and/or other viscous materials are described. In one embodiment, a rheometer is connected to an associated system with a bent, curved, or bendable tube to permit the rheometer to measure rheological properties in locations where the rheometer could not otherwise be located due to the presence of obstructions. Embodiments including rigid straight tubes for connecting a rheometer to an associated system are also described. In another embodiment, a flow-through rheometer is connected to an industry standard ½-20 thermowell aperture that is typically used for attaching temperature and pressure probes to a vessel containing a viscous material such as an extruder or injection molding system.

Abstract: A method for controlling the exposure of a selective laser sintering or laser melting apparatus. The method includes providing a selective laser sintering apparatus or laser melting apparatus that uses successive solidification of layers of a powder-type construction material that can be solidified using radiation.

Abstract: There is disclosed a method for determining the heating value of a fuel, the fuel comprising at least one hydrocarbon including a first hydrocarbon present in the highest molar concentration, the method comprising: measuring the stoichiometric oxidation molar flow ratio of the fuel; determining the ideal molar heating value (HVm,i) from the measured stoichiometric oxidation molar flow ratio; measuring the molar concentration of the first hydrocarbon; and determining the real molar heating value (HVm,r) from the ideal molar heating value (HVm,i) and the molar concentration of the first hydrocarbon. An apparatus is also disclosed.

Abstract: An apparatus and method for determining the average molecular weight of a complex mixture from a plurality of test samples of the complex mixture are disclosed. The method includes a) providing a chamber having two fixed conditions and one variable condition selected from three state variables of temperature, pressure and volume; b) introducing a test sample of known mass into the chamber; c) setting operating conditions of the state variables such that the test sample will be fully vaporized into a gaseous state without decomposition or chemical reaction; and d) measuring the change of the variable condition after full vaporization of the test sample is achieved. Steps b-d are repeated for several test samples having different masses. The average molecular weight of the complex mixture is determined as a linear gradient (slope) of the relationship for the change of variable condition as a function of test sample mass.

Abstract: A method and a device for monitoring the combustion of fuel in a power station are provided. An actual concentration distribution of a material in a combustion chamber is measured, the actual concentration distribution is evaluated, taking into consideration a combustion stochiometry, and conclusions are drawn regarding a composition of the fuel on the basis of the evaluation that has been carried out.

Abstract: Composite films comprising an organic salt (or GUMBOS) such as 1-n-butyl-2,3-dimethylimidazolium hexafluoro-phosphate and a polymer such as cellulose acetate are prepared. These films are useful in detecting vapors of volatile organic compounds, and in determining their molecular weights. A quartz crystal microbalance-based sensor was designed by depositing a thin film of this composite material on the gold electrode surface of a quartz crystal resonator. The sensor exhibited rapid response toward a variety of volatile organic compounds, and complete regeneration, high sensitivity, low detection limits, and wide dynamic ranges. The ratio of the change in frequency to the change in motional resistance is a concentration-independent quantity that is proportional to the molecular weight of the absorbed chemical species. These properties facilitate the easy identification and molecular weight determination of a broad range of organic vapors.

Abstract: The present invention provides a conductive polymer in which, when being formed into a coating film, foreign materials are difficult to be generated even the passage of time and a quality control method for a conductive polymer and has a repeating unit which is represented by the following general formula (1). The present invention also provides a quality control method for conductive polymers wherein conductive polymers with an area ratio (Y/X) of 0.60 or less are selected. In the formula R1 to R4 are each independently —H, a linear or branched alkyl group having 1 to 24 carbon atoms, a linear or branched alkoxy group having 1 to 24 carbon atoms, an acidic group, a hydroxyl group, a nitro group, —F, —Cl, —Br or —I; and at least one of R1 to R4 is an acidic group or a salt thereof.

Abstract: It has been found that certain cells in culture can convert more than about 0.002 percent of the carbon available in the cell culture medium into isoprene. These cells have a heterologous nucleic acid that (i) encodes an isoprene synthase polypeptide and (ii) is operably linked to a promoter. In some cases, these cells are cultured in a culture medium that includes a carbon source, such as, but not limited to, a carbohydrate, glycerol, glycerine, dihydroxyacetone, one-carbon source, oil, animal fat, animal oil, fatty acid, lipid, phospholipid, glycerolipid, monoglyceride, diglyceride, triglyceride, renewable carbon source, polypeptide (e.g., a microbial or plant protein or peptide), yeast extract, component from a yeast extract, or any combination of two or more of the foregoing. The isoprene produced in such a cultured medium can then be recovered and polymerized into synthetic rubbers and other useful polymeric materials.

Abstract: Methods and devices are provided for controlling a fluid flow over a sensing surface within a flow cell. The methods employ laminar flow techniques to position a fluid flow over one or more discrete sensing areas on the sensing surface of the flow cell. Such methods permit selective sensitization of the discrete sensing areas, and provide selective contact of the discrete sensing areas with a sample fluid flow. Immobilization of a ligand upon the discrete sensing area, followed by selective contact with an analyte contained within the sample fluid flow, allows analysis by a wide variety of techniques. Sensitized sensing surfaces, and sensor devices and systems are also provided.

Abstract: The present invention provides several methods of determining values of physical or chemical properties of polymers. In these methods, at least two polymer training samples are provided. Characteristics of the polymer microstructures of the training samples are correlated with values of physical or chemical properties of the training samples. These correlations are subsequently applied to the respective characteristics of polymer test samples in order to determine the values of physical or chemical properties of the test samples.

Abstract: A system for characterizing a membrane is disclosed. The system includes a container configured to dissolve a first large molecular weight marker and a second large molecular weight marker into a solution, wherein the container is connected to a reservoir. The reservoir configured to receive the solution. A filtration unit is connected to the reservoir, where the filtration unit is configured to separate the first large molecular weight marker and the second large molecular weight marker from the solution. A measuring system is configured to determine if the first large molecular weight marker is equal to or larger than a first target concentration, where if the first large molecular weight marker is equal to or larger than the first target concentration then the first large molecular weight marker it meets a first criteria for rejection by said membrane.

Abstract: Polymer fractions such as polyethylene fractions can be produced that have a PDI less than about 2.3 and a Mw greater than about 1,000,000 g/mol, 3,000,000 g/mol, or 6,000,000 g/mol. Such polyethylene fractions are separated from a UHMWPE parent polymer by first dissolving the parent polymer in a relatively good solvent. The conditions employed for such dissolution are selected to reduce the degradation of the parent polymer. The resulting parent solution is transported into a fractionation column in which a support is disposed. The fractionation column is thereafter operated at conditions effective to form a precipitate on the support comprising the desired polyethylene fraction. The polyethylene fraction may then be recovered from the fractionation column by repeatedly displacing a solvent/non-solvent mixture into the column to dissolve the polyethylene fraction. The relative concentrations of the solvent and the non-solvent are based on a solvent gradient profile of the polyethylene parent polymer.

Abstract: A method of monitoring the fire resistance of hydraulic fluids involves measuring a property of the hydraulic fluid that changes as the hydraulic fluid is used; relating the measurement to the fire resistance of the hydraulic fluid; and if necessary, taking remedial action in order to improve the fire resistance of the hydraulic fluid. A suitable property is the molecular weight of polymer anti-mist additives such as polymethyl methacrylate and the fire resistance may be improved by adding to the hydraulic fluid, a concentrate of the polymer in a suitable solvent when the measured molecular weight falls below an acceptable value.

Abstract: The present invention relates to the field of tissue processing, particularly, to the treatment of fluids used in tissue processing. In one embodiment the present invention provides for treating a tissue processing fluid comprising first processing fluid comprising a first processing fluid and a second contaminating fluid, by: gradually varying the pressure of the fluid from an initial pressure level to a first pressure level such that the fluid remains below a vaporizing point of the second contaminating fluid and, heating the fluid to at least a vaporizing temperature of the second contaminating fluid. In another embodiment, the present invention removes the second contaminating fluid from the fluid by varying at least one of the pressure and temperature of the fluid so as to allow the second contaminating fluid to vaporize. Alternatively, an embodiment of the present invention interleaves the step of removing with one or more tissue processing protocol steps.

Abstract: Polymer fractions such as polyethylene fractions can be produced that have a PDI less than about 2.3 and a Mw greater than about 1,000,000 g/mol, 3,000,000 g/mol, or 6,000,000 g/mol. Such polyethylene fractions are separated from a UHMWPE parent polymer by first dissolving the parent polymer in a relatively good solvent. The conditions employed for such dissolution are selected to reduce the degradation of the parent polymer. The resulting parent solution is transported into a fractionation column in which a support is disposed. The fractionation column is thereafter operated at conditions effective to form a precipitate on the support comprising the desired polyethylene fraction. The polyethylene fraction may then be recovered from the fractionation column by repeatedly displacing a solvent/non-solvent mixture into the column to dissolve the polyethylene fraction. The relative concentrations of the solvent and the non-solvent are based on a solvent gradient profile of the polyethylene parent polymer.

Abstract: A method of determining an average length of reinforcing fiber in a sample of reinforcing fibers is disclosed. A sample of reinforcing fibers is weighed to obtain a total sample weight. The sample of reinforcing fibers is placed in a fiber separating mechanism and suspended in water. The water is stirred after which the water is allowed to settle such that the sample of reinforcing fiber divides into a plurality of fractions in separate sections of the fiber separating mechanism. Each fraction has reinforcing fibers of substantially similar lengths and is separately weighed. An average fiber length is calculated from the relative weights of each of the plurality of fractions and the total sample weight. In addition, a method of determining an average length of a reinforcing fiber in a composite material having a resin and a plurality of reinforcing fibers is disclosed.

Abstract: A rapid analysis method for the determination of polymer average molecular weight separates the polymer's high molecular weight fraction and determines its average molecular weight using a molar mass detector and a concentration detector. The method avoids time consuming sample preparation, allows for separation of interfering low molecular weight components, and is suitable for automation.

Abstract: A method and apparatus for studying the properties of a fluid are provided in which in which a rheometer is used to obtain, for example, value(s) indicative of the shear stress in the fluid to thereby obtain a set of data. The data is then directly compared using, for example, multivariate analysis, with previously obtained data corresponding to a fluid(s) with known rheological properties. The results of this comparison can then be used, for example, to control a manufacturing process.

Abstract: A method of measuring a concentration and a molecular weight distribution of glue or gelatin contained in an electrolyte, which comprises high performance liquid chromatography combined with column switching.

Abstract: A method of determining the real time bubble point pressure of a fluid originating from a subsurface earth formation using an adjustable choke positioned downhole adjacent to the formation. The adjustable choke is placed into communication with the wellbore fluid flowing from the formation to the surface. The adjustable choke has a remotely adjustable choke opening for selectively restricting the flowrate of the fluid flowing through the choke. The adjustable choke has a pressure sensor for measuring the fluid pressure downstream of the choke opening. The method includes obtaining downstream fluid pressure data as a function of choke size for generating a plot of downstream pressure versus choke size data which exhibits substantially linear behavior having two different slopes.