Abstract: A scroll pump has a metallic bellows that angularly synchronizes the stationary and orbiting scroll blades of the pump, and a hack-up system for the bellows. The back-up system consists of pins integral with and fixed relative to one of the stationary and orbital parts of the scroll pump, and a guide part that is integral with and fixed relative to the other of the stationary and orbital parts. The back-up system may be a non-contacting hack-up system in which there is no contact between the pins and guide part during normal operation of the pump. Therefore, no particles are created by a wearing away of such parts which would otherwise have the potential to contaminate the fluid being worked by the pump and reduce the useful life of the pump.

Abstract: A system for chilling a pumping system includes a Peltier cooling element, and first and second heat exchangers. The Peltier element is arranged near a pump head of a pump such that the Peltier element and the pump head are in thermal contact, where the Peltier element chills the pump head and a mobile phase flowstream prior to fluid from the mobile phase flowstream entering the pump. The first heat exchanger is attached to the Peltier element, and removes heat from the Peltier element using a circulating fluid. The second heat exchanger cools the circulating fluid, where the Peltier element and the pump head are arranged in an area that is isolated from the second heat exchanger.

Abstract: Compound tags and shifting agents are provided that find use in ion mobility spectrometry (IMS), mass spectrometry (MS), or a combination of IMS and MS, and which can substantially increase separation of multiple components in complex samples and facilitate quantitative and multiplexed analyses. In some cases, the compounds include a linker and a normalizing group, each including a structural unit and separated by a cleaveable group, and a crown ether. Also provided are methods for analyzing peptides in a sample. In some cases, the method includes coupling the compound to peptides which include a terminal guanidinium moiety capable of forming an intra-molecular complex with the crown ether.

Abstract: A vacuum type of scroll pump includes a frame, a stationary plate scroll, an orbiting plate scroll, a non-energized type of tip seal or seals, an eccentric drive mechanism assembled to and supported by the frame and to which the orbiting plate scroll is assembled so as to be drivable by the eccentric drive mechanism in an orbit about a longitudinal axis of the pump, and a mechanism for adjusting the seal(s) created by the tip seal(s) without having to disassemble any of the frame, plate scrolls or parts of the eccentric drive mechanism from one another, i.e., while a pump head assembly of the pump remains intact.

Abstract: This disclosure provides a method for adding an adaptor to a genomic sequence by invasive cleavage, as well as a kit for performing the method. In some embodiments, the method comprises: a) hybridizing genomic DNA to an adaptor comprising a double stranded region and a single stranded region comprising a 5? overhang to produce a substrate for a flap endonuclease; b) cleaving the substrate using the flap endonuclease; c) ligating the recessed end of the double stranded region to the fragment to produce an adaptor-ligated DNA; d) intramolecularly ligating the ends of the adaptor-ligated DNA to produce a circular DNA molecule; and e) enzymatically processing the circular DNA molecule using an oligonucleotide that hybridizes to the adaptor and an enzyme. A kit for performing the method is also provided.

Abstract: A method for controlling operation of a pump unit, where the pump unit includes a primary piston pump having a primary piston and a secondary piston pump having a secondary piston. The primary piston pump is fluidically connected with the secondary piston pump. The primary piston pump includes an inlet valve and an outlet valve, and the pump unit operates periodically according to a pump cycle. The method includes determining a fluid pressure of fluid dispensed by the pump unit, and performing a closed loop control of a position of the primary piston in dependence on the fluid pressure of the fluid dispensed by the pump unit during a first time interval of the pump cycle.

Abstract: A scroll pump includes a frame, a stationary plate scroll, an orbiting plate scroll, a tip seal(s), an eccentric drive mechanism which drives the orbiting plate scroll, and an axial compliance system. The eccentric drive mechanism includes a crankshaft, and bearings and a counterbalance disposed on the crankshaft. The counterbalance is mounted so as to be slidable along the crankshaft in the axial direction of the crankshaft. The axial compliance system includes a flexure and one set of springs for pre-loading the bearings. The flexure is interposed between one of the bearings and the counterbalance. The flexure allows the orbiting plate scroll to move away from the stationary plate scroll in the case of an assembly process which would otherwise result in the tip seal(s) being too forcefully engaged with the plate of the opposing plate scroll.

Abstract: A fluidic apparatus for a sample separation system includes a fluid inlet path for supplying a fluid, an inlet sensor adapted for measuring a flow rate of the fluid in the fluid inlet path, a splitting point arranged downstream of the fluid inlet path and adapted for splitting the fluid into a first path and into a second path, and a second path sensor adapted for measuring a flow rate of a part of the fluid conducted into the second path.

Abstract: An orbiting plate scroll of a scroll pump includes an orbiting plate having a first side and a second side, an orbiting scroll blade projecting in an axial direction from the first side of the orbiting plate, and a flexure whose compliance is in the axial direction. The flexure is coupled to the orbiting plate at the second side of the orbiting plate, and couples the orbiting plate and orbiting scroll blade to bearings that allow for free rotation of the orbiting plate scroll about a longitudinal axis, while constraining motion of the orbiting plate scroll in the remaining degrees of freedom.

Abstract: A drive mechanism for back pressure regulator used in liquid chromatography, supercritical fluid chromatography, or supercritical fluid extraction allows very fine automated control over a very wide range of pressures by combining a linear actuator compressing a spring, pushing a pin. The nozzle assembly of the regulator comprises a flow through chamber containing a diaphragm and a seat, in which the pin pushes the diaphragm against the seat, together with an upstream pressure sensor and electronic feedback control to the motor of the actuator. The BPR of the embodiments exhibits high pressure stability and extremely low pressure noise, even at moderate to high pressures. The exemplary BPR can be use at either constant pressure or to generate pressure programs where the pressure is varied versus time. Further, the nozzle assembly has a field-replaceable head, requiring no mechanical adjustment on replacement.

Abstract: In a tandem mass spectrometry system, a first mass analyzer filters parent ions using a wide mass passband with a narrow rejection notch defined according to a modulation format. A wide mass range of parent ions is transmitted to an ion fragmentation device. Daughter ions produced thereby are transmitted to a second mass analyzer to produce a daughter ion mass spectrum. The modulation of the measured daughter ion mass spectrum, when correlated with the passband modulation of the first mass analyzer (i.e., parent ion spectrum), allows definitive identification of each daughter mass peak with the appropriate parent ion. Due to the wide mass passband, the ion detector signal is in proportion to the increased ion flux passed by the first mass analyzer.

Abstract: An apparatus includes an electromagnetic which supports propagation of an electromagnetic wave in a first direction between a first end thereof and a second end thereof, and an electromagnetic-field shaping structure within the electromagnetic waveguide. The electromagnetic-field shaping structure defines a channel extending from a first aperture in a first wall of the apparatus to a second aperture in a second, opposite, wall. The channel has an axis extending in a second direction which is nonparallel with the first direction. The distance between the first aperture and the second aperture in the second direction is less than the width of the interior region of the waveguide at the first and second ends thereof. In some embodiments, a plasma torch is disposed within the channel. The length of the torch closely matches its interaction region.

Abstract: A system for performing optical spectroscopy measurements includes a light source for generating an input optical beam and an interferometer. The interferometer includes a beam splitter that splits the input optical beam into first and second light beams; a first light path that directs the first light beam through a sample containing an analyte to a first output port; and a second light path that directs the second light beam to the first output port. At least one of the first and second light paths adjusts a relative phase of a corresponding one of the first and second light beams, so that the first and second light beams are out of phase at the first output port, substantially canceling background light and outputting sample light corresponding to a portion of the first light signal absorbed by the sample in the sample cell. A detection system detects the output sample light.

Abstract: A scroll pump has a tip seal between an axial end of the scroll blade of one of stationary and orbiting plate scrolls of the pump and the plate of the other of the stationary plate and orbiting plate scrolls. The scroll pump may have a ballast gas supply system and use the operation of the ballast gas supply system to assess the condition of the tip seal. Alternatively, the scroll pump may have two pressure sensors that sense pressure at two locations spaced along a compression mechanism of the pump to assess the condition of the tip seal.

Abstract: A sample separation apparatus includes a fluidic valve including a first inlet fluidically coupled to one of a first fluid drive and a second fluid drive, and a second inlet fluidically coupled to the other of the first fluid drive and the second fluid drive. The fluidic valve includes at least two different sets of storage paths, wherein each set of storage paths comprises a first storage path. The first storage path of a first set of said at least two sets of storage paths has a first volume, and the first storage path of a second set of said at least two sets of storage paths has a second volume different from the first volume. The fluidic valve is configured for selectively switching one set of the least two sets of storage paths to the first inlet and the second inlet.

Abstract: An apparatus and method for measuring the attenuation and dispersion introduced by a sample into an optical signal are disclosed. The apparatus includes a chirped light source, a beam splitter and an optical detector. The beam splitter splits the optical signal generated by the light source into a reference optical signal and a sample optical signal. The sample and reference optical signals are mixed on the detector after the sample optical signal has traversed an experimental sample thus generating a signal having an AC component related to an attenuation and a dispersion introduced by the experimental sample. The optical paths traversed by the reference and sample optical signals between the beam splitter and the detector are chosen such that the reference optical signal and the sample optical signal overlap in time but do not arrive at the optical detector at the same time.

Abstract: Parts of a pump head of a scroll pump facilitate an assembly process in which the stationary and orbiting scroll blades of the pump are angularly aligned or synchronized with one another. A metallic bellows of the pump head provides a primary means of synchronizing the stationary and orbiting scroll blades. The assembly process may be carried out using a fixture configured to be mountable to an assemblage including the bellows and the orbiting plate scroll. The fixture has a reference feature, and the orbiting plate scroll or the frame has another reference feature that can be aligned with the reference feature of the fixture, in the circumferential direction of the bellows, during the course of the assembly process.

Abstract: A plasma generation device, a system including a plasma generation device, and a method of generating plasma and vacuum UV (VUV) photons are described. In a representative embodiment, plasma generation device, includes: a substrate having a first surface and a second surface; a resonant ring-shaped structure disposed over the first surface of the substrate, the resonant ring-shaped structure having dimensions selected to support at least one standing wave having more than one electric field maximum along a length of the resonant ring-shaped structure; a ground plane disposed on the second surface of the substrate; and an apparatus configured to provide a gas at locations of the electric field maxima.

Abstract: A shear valve, for use in a high performance liquid chromatography system, comprises a first shear valve member and a second shear valve member. At least one of the first and second shear valve members is adapted to be moved with respect to the other. One of the first and second shear valve members comprises a plurality of ports, and the other comprises at least one fluid path for fluidly coupling respective ones of the ports in dependency on a relative movement position of the first and second shear valve members with respect to each other. The first shear valve member is at least partially coated with or comprised of silicon carbide.

Abstract: An apparatus that facilitates the manual sorting of objects is disclosed. The apparatus includes a display surface having a surface that can be selectively illuminated and that is adapted for receiving the objects. An identification reader reads identification information stored on the objects. A controller causes an area on the display surface corresponding to one of the objects to be illuminated based on the identification information and indicates a location to which the illuminated object is to be moved. In one aspect of the invention, the display surface includes an area adapted for positioning a receiver for the objects. The display surface provides an indication of a position in the receiver at which the one of the objects is to be placed.