Abstract: System and methods are described for dynamically controlling operation of a rheometer. A program is created on a programming interface for executing a test upon a sample in a rheometer by receiving user selections of a plurality of nodes and connections of each node to another node according to directional connection indicators. Nodes indicate steps for performing a test upon a sample or configuring a rheometer for performing a test upon a sample. Scripts are created for generating a sequence of instructions to the rheometer. The scripts include instructions for performing steps indicated by each of the selected nodes and in accordance with the directional connection indicators. Low-level instructions are downloaded from the scripts for execution in the rheometer, and drivers in the rheometer are instructed for performing the downloaded instructions.

Abstract: A rheometric system includes an optical encoder coupled to a rotating shaft and configured to detect a rotational position of the shaft with respect to a reference. The rotational information is forwarded to a program or memory. An optical rotation plate is mechanically fastenable to the rotating shaft. A laser is provided to probe optical properties of a fluid sample proximate to the optical rotation plate. The system includes a detector system for measuring laser light scattered or transmitted through the sample chamber. The detector system is coupled to a memory that stores optical data collected after light impinges on the optical plate. Experimental fluid sample optical data and background optical data are each stored as a data structure that creates a point by point map of rotational position of the sample plate with the optical data collected thereat.

Abstract: Embodiments of the present invention are directed to apparatus and methods for performing mass spectrometry. Data pair information is subjected to an ion audit process in which data pair information that relates to scored compounds is subtracted from the data pair information. The depleted information more readily reveals data pair information for compounds present with smaller signals.

Abstract: A method (100) for performing chemical analyses includes digesting a reference sample to obtain precursors associated with a peptide in the sample (110), separating the precursors to determine values associated with retention times of the separated precursors (120), ionizing the separated precursors to form precursor ions (130), mass analyzing the precursor ions to determine values associated with mass and with ion intensity (140), and storing a <?fcfile of the polypeptide defined by the determined values (150). A subject sample is analyzed (160), and the polypeptide is detected in the subject sample in response to a match between subject-sample and profile values. An apparatus (900) for performing chemical analyses includes a chromatography module (904), a mass-spectrometry module (912), and a computer module (926).

Abstract: Disclosed is a chromatographic system and method which includes a passive pre-heater assembly. In the inventive system and method a fluid mixture is supplied from an injector to the pre-heater assembly and then to a chromatographic column having an active heating source. The pre-heater assembly includes a convoluted tube with first and second ends and a fluid passage extending centrally therebetween, first and second end fittings attached respectively to the first and second ends of the convoluted tube, and a thermally conductive film attached to an outer surface of the convoluted tube. The first end fitting is adapted for fluidly connecting the first end of the convoluted tube to the injector and the second end fitting is adapted for fluidly connecting the second end of the convoluted tube to the chromatographic column.

Abstract: A modulated differential scanning calorimeter that accounts for heat flow due to evaporative solvent loss. The calorimeter modulates the temperature applied to a sample and a reference to determine the amount of heat flow that is due to evaporation. By calculating the amount of heat flow due to evaporation, the user can determine how much of the heat flow of any given well is due to the process of interest as opposed to evaporation.

Abstract: A solvent delivery subsystem for a chromatography device performs relatively low pressure, high flow mixing of solvents to form a gradient and subsequent high pressure, low flow delivery of the gradient to the separation column. The mixing of the gradient is independent and does not interfere with the gradient delivery. To form the gradient, the outputs of an aqueous pump and an organic pump are mixed to fill a storage capillary while a downstream point from the storage capillary is vented to atmosphere. After gradient formation, the vent to atmosphere is closed, the solvent delivery system rises to high pressure, and only the aqueous pump runs for gradient delivery. To maintain integrity of the fluid stream, the solvent delivery system uses feed forward compensation and controls at least one parameter selected from the group consisting of pressure and flow in the conduit means to follow a gradual ramp.

Abstract: The present invention relates to porous inorganic/organic homogenous copolymeric hybrid material materials, including particulates and monoliths, methods for their manufacture, and uses thereof, e.g., as chromatographic separations materials.

Abstract: Systems and methods for minimizing extraneous forces and calculating corrected weights of samples based on buoyancy factors for a thermogravimetric analyzer (TGA). The TGA includes a balance chamber and a furnace configured to heat a sample. A null balance is provided in the balance chamber and is used to measure the sample weight change during heating. The furnace includes a cylinder open at the top to receive a sample. The bottom of the cylinder is closed except for a small hole that allows a thermocouple to pass through. An infrared heat source may be provided to heat the cylinder. The balance chamber can be thermally isolated from the furnace using an actively cooled plate and a system of heat shields disposed between the furnace and balance chamber. A thermocouple disk is further provided to limit gas flow in the furnace and increase reliability of sample weight measurements.

Abstract: The present invention provides a device, system, and associated methods to actively or passively sample air by directing it onto the surface of a porous light-absorbing semiconductor, for example, a desorption/ionization on porous silicon (“DIOS”) chip. Upon adsorption of an analyte, the surface may be analyzed directly by laser desorption/ionization time-of-flight mass spectrometry. Because the process of laser desorption/ionization and subsequent mass detection does not require elevated temperatures, thermal degradation of analytes is avoided.

Abstract: A method includes compressing chemical-analysis data points with no loss of information, generating, from the stored data points, nested data arrays, storing the nested data arrays in a video memory, rendering an image from the nested data arrays, and displaying the rendered image. A chemical-analysis instrument includes a chromatography module, a mass-spectrometry module that receives an eluent from the chromatography module, a computer unit that receives data points from the chromatography and mass-spectrometry modules, and a monitor for displaying rendered images.

Abstract: Embodiments of the present invention feature heat exchange surfaces having a layer or coating having a lower surface tension than water, to repel water and prevent the formation of condensate on said surface.

Abstract: Embodiments of the present invention are directed to porous resins for solid phase extractions. The resins feature at least one hydrophobic component, at least one hydrophilic component and at least one ion exchange functional group. The resins exhibit superior wetting and ion exchange performance.

Abstract: An embodiment of the present invention is a method for creating and maintaining a partial vapor pressure in a sample chamber of a sorption analyzer. A first dry gas flow is purged from a first mass flow controller through a saturator to produce a near-saturated gas flow. The near-saturated gas flow is mixed with a second dry gas flow from a second mass flow controller to produce a mixed gas flow with a predetermined partial vapor pressure. The mixed gas flow is directed into the sample chamber. If the lowest possible vapor pressure is required in the sample chamber, the first dry gas flow is directed around the saturator to the sample chamber and vapor migrating from the saturator is vented to the atmosphere.

Abstract: Novel material for chromatographic separations, processes for its preparation, and separations devices containing the chromatographic material. In particular, the disclosure describes porous inorganic/organic hybrid particles having a chromatographically-enhancing pore geometry, which desirably may be surface modified, and that offer more efficient chromatographic separations than that known in the art.

Abstract: Apparatus for the detection of analytes in a fluid, for example the eluant from a liquid chromatography is described. Solvent is evaporated from the eluant to produce a stream of particles when analyte is present in the fluid. The resultant stream of particles is passed through one or more beams of radiation, typically visible light, and radiation scattered by the particles is detected at least at a first angle to a beam of radiation and at a second, different, angle to a radiation beam to produce a signal indicative of the presence of the analyte. Chromatographic apparatus incorporating the detector and methods of operating the detector and chromatographic apparatus are also described.

Abstract: A method of calibrating the torque outputs of a rheometer by using a calibrating object with a certified moment of inertia, measuring the moment of inertia of the calibrating object using the rheometer, and calculating the torque adjustment factor by dividing the certified moment of inertia value by the measured moment of inertia value. The torque adjustment factor is applied to correct subsequent measurements of rheological properties conducted using the rheometer. The torque adjustment factor may be double-checked for reproducibility by measuring the moment of inertia of the calibrating object, correcting it with the torque adjustment factor, and comparing it with its certified moment of inertia value.

Abstract: Embodiments of the present invention are directed to an apparatus and method for performing parallel processes. One embodiment of the present invention is directed to an apparatus for performing a process having a plurality of steps in which each step is performed in a vessel by flowing a fluid through said vessel. The steps of the process comprise at least a first step and at least one subsequent step. At least one of the subsequent steps is a final step, and each step has a time associated with its performance, a step period. At least one step has a longest step period, and the total number of steps, times the longest step period equals a process period. The apparatus comprises a plurality of vessels. Each of the plurality of vessels is for performing sequentially all the steps of the process in the process period and each of the plurality of vessels is for performing each step of the process in the longest step period.

Abstract: An optical rheometer system includes a rheometer chamber that can retain a fluid sample to be measured. A light source is provided that creates a light beam incident on the fluid sample. A Peltier heating plate is provided that has a channel region located within the plate. The channel region is configured to substantially transmit a light beam emitted from the light source and incident on the Peltier heating plate. In one embodiment, a rotating optical plate is provided opposed to a first surface of the Peltier plate. The rotating optical plate is substantially transparent such that light from a light beam emerging from the channel region of the Peltier plate can pass through the optical plate and be recorded at a detector. Peltier elements in the Peltier heating plate are arranged to provide uniform heating of sample fluid located on the first surface of the Peltier heating plate. The Peltier elements are further arranged to permit light to pass through the channel substantially unattenuated.

Abstract: Systems, devices, and methods to mitigate the pressure disturbance associated with the injection of low-pressure analyte samples into a high-pressure HPLC fluid stream (52), to enhance chromatographic performance related to retention time and reproducibility. The preferred embodiment coordinates the injection run with active pressure control of a binary solvent delivery system (30) to virtually eliminate the customary pressure drop when the low-pressure loop is brought on line. An additional benefit that enhances reproducibility is accomplished by forcing a consistent timing relationship between the injection run, the mechanical position of the delivery pump pistons, and the start and subsequent gradient delivery.