308results about How to "Accurate mass" patented technology

The invention presents a method for examining genetic material (deoxyribonucleic acid, DNA) to detect the presence of pre-known mutations, especially single nucleotide polymorphisms (SNP), using mass spectrometry with ionization by matrix-assisted laser desorption (MALDI). The invention uses nucleoside triphosphates with modified sites for the method of primer extension in a duplicating, enzymatic reaction and at least partially removal of primers from the extension product, in combination with product neutralization by chemical treatment of the modified sites, so that the resulting DNA products can be, by using special matrix materials, preferredly ionized in an adduct-free form over other constituents in the reaction solution without any further cleaning. The method is particularly suitable for simultaneous identification of several mutations by multiplexing.

A radiation imaging apparatus in which early recognition of breast cancer can be made possible by acquiring both a radiation tomographic image that accurately displays a tumor mass and a radiation planar image that accurately displays calcification. The apparatus includes an image processing unit for generating a tomographic image signal in a first imaging mode and generating a planar image signal in a second imaging mode, a computing unit for computing an imaging direction for obtaining a radiation planar image based on a location designated in a radiation tomographic image, and a control unit for controlling a rotational driving device and a radiation generating unit to obtain the radiation tomographic image in the first imaging mode, and controlling the rotational driving device according to the computed imaging direction and controlling the radiation generating unit to obtain the radiation planar image in the second imaging mode.

Accurate mass measurement is carried out for product ions of a sample. A method for accurate mass determination of ions with Trap-TOF / μs includes steps of generating ions of an analyte sample and a standard material; introducing the ions of the analyte sample and the standard material together into an ion trap to trap them; selecting a precursor ion from the ions of the analyte sample to leave the precursor ion and a standard material ion in the ion trap and eliminate other ions; exciting and dissociating the precursor ion to generate product ions; ejecting the precursor ion, its product ions, and the standard material ion trapped in the ion trap to introduce these ions into the TOF mass spectrometer; and measuring a mass spectrum with the TOF mass spectrometer, where correction for accurate masses of the product ions is carried out based on the standard material ion measured.

A time of flight type mass spectrometer (TOF-MS) of the present invention includes: a flight space containing a loop orbit on which ions fly once or more than once; a flight controller for making ions of a same mass to charge ratio fly the loop orbit at several values of number of turns; a flight time measurer for measuring a length of flight time of the ions; and a processor for determining the mass to charge ratio of the ions based on a relationship between the value of number of turns and the length of flight time of the ions. The speed of ions flying a loop orbit depends on their mass to charge ratios. For ions of the same mass to charge ratio, the difference between the lengths of flight time of the ions flying the loop orbit N turns and of the ions flying the loop orbit N+1 turns depends on the speed of the ions, so that the difference depends on the mass to charge ratio of the ions. The difference in the length of flight time is unrelated to the variation in the starting time (jitter), variation in the detection timing (jitter), etc, so that the value of the mass to charge ratio can be precisely determined free from errors caused by such disturbing factors.

A pressure and flow calculation technique can be used in a distributed process network simulation system that uses the sequential solving method to perform better or faster simulations of a process flow, especially with respect to process junction nodes at which flow either converges or diverges. The pressure and flow variable determination technique uses a grouped node identification technique that identifies a local set of nodes for each junction node of the process network to use when solving for the pressure at the junction node, a grouped node iteration technique that uses the grouped set of nodes at each junction node to perform iterative pressure calculations at the junction node, and a flow-based pressure calibration technique at each junction node to enable the system to perform highly accurate pressure and flow variable determination at each junction node in real-time.

The invention relates to a quality detection method of a traditional Chinese medicine preparation. The method comprises the following steps: respectively taking gallic acid, albiflorin, paeoniflorin,ferulic acid, liquiritin, beta-ecdysterone, senkyunolide I, glycyrrhizin, cinnamic acid, cinnamyl aldehyde, paeonol, ammonium glycyrrhizinate and ligustilide as reference substances, and establishinga fingerprint spectrum of the traditional Chinese medicine preparation by adopting high performance liquid chromatography; identifying Chinese angelica, the rhizome of chuanxiong, radix paeoniae alba,moutan bark, ginseng, cassia bark, licorice root and the root of bidentate achyranthes of the traditional Chinese medicine preparation by adopting thin-layer chromatography. The traditional Chinese medicine preparation is prepared by using the following raw materials: Chinese angelica, the rhizome of chuanxiong, radix paeoniae alba, cassia bark, moutan bark, zedoray rhizome, ginseng, licorice root and the root of bidentate achyranthes. With the two detection ways, comprehensive quality evaluation can be conducted on the meridian-warming decoction traditional Chinese medicine preparation. Themethod is simple, convenient, high in accuracy and high in reproducibility; a scientific basis can be provided for quality detection and evaluation of the meridian-warming decoction traditional Chinese medicine preparation, and the product quality is effectively controlled.

A model-based estimation of mass airflow is provided which provides an accurate estimation of mass airflow without introducing undesirable time delays characteristic of filtered mass airflow signals.

The invention discloses a heavy vehicle mass and mass center detection device. The existing devices mainly use side weighing methods, the number of sensors is small, and the devices have certain limitations. The detection device comprises a foundation pit, a four-degree-of-freedom (4DOF) platform, pressure sensors, a vehicle to be detected and a horizontal table board; the 4DOF platform is arranged in a foundation, and a plurality of pressure sensors are arranged on the upper surface of an upper cylindrical portion of an upper platform of the 4DOF platform from center to periphery along an Archimedes spiral; and the horizontal table board is covered on the pressure sensors, and the vehicle to be detected is arranged on the horizontal table board. The 4DOF platform can rotate along an X axis, a Y axis and a Z axis, and the pressure sensors in the device work out the mass and the position of the mass center of the vehicle rapidly according to different positions and pressure gained in the detection during rotating movement. According to the detection device, the measurement accuracy of the sensors is guaranteed by arrangement optimization of the sensors, and the measured mass and the position of the mass center are more accurate and reliable.

Accurate mass measurement is carried out for product ions of a sample. A method for accurate mass determination of ions with Trap-TOF / μs includes steps of generating ions of an analyte sample and a standard material; introducing the ions of the analyte sample and the standard material together into an ion trap to trap them; selecting a precursor ion from the ions of the analyte sample to leave the precursor ion and a standard material ion in the ion trap and eliminate other ions; exciting and dissociating the precursor ion to generate product ions; ejecting the precursor ion, its product ions, and the standard material ion trapped in the ion trap to introduce these ions into the TOF mass spectrometer; and measuring a mass spectrum with the TOF mass spectrometer, where correction for accurate masses of the product ions is carried out based on the standard material ion measured.

The present invention relate to an autoantigen screening method by combining immunoaffinity chromatography, disease-related cell lines, and mass spectrometry technology, which offers greater screening efficiency and speed than known technologies. The method for screening autoantigen by using autoantibodies in patient's body by utilizing the chromatographic column packed with autoantibodies, through the affinity between autoantibody and autoantigen, and the extract of disease-related cell lines or pathological tissues, whereby an autoantigen screening platform is established.