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A time-of-flight mass spectrometer (TOFMS) consists of a mass analyzer and a detector. An ion source (either pulsed or continuous) is used for lab-related TOF experiments, but not needed for TOF analyzers used in space, where the sun or planetary ionospheres provide the ions. The TOF mass analyzer can be a linear flight tube or a reflectron.
Time of flight (ToF) is the measurement of the time taken by an object, particle or wave (be it acoustic, electromagnetic, etc.) to travel a distance through a medium. This information can then be used to measure velocity or path length, or as a way to learn about the particle or medium's properties (such as composition or flow rate).
TOFD has a dead zone where it is not sensitive to defects, hence TOFD ought always to be supplemented by a conventional pulse-echo examination or phased array. The pulse echo probes are commonly mounted on the same buggy as the TOFD probes. Requires ultrasound technicians with advanced training.
Principle of ultrasonic testing. LEFT: A probe sends a sound wave into a test material. There are two indications, one from the initial pulse of the probe, and the second due to the back wall echo. RIGHT: A defect creates the third indication and simultaneously reduces the amplitude of the back wall indication.
Time of flight of a light pulse reflecting off a target. A time-of-flight camera (ToF camera), also known as time-of-flight sensor (ToF sensor), is a range imaging camera system for measuring distances between the camera and the subject for each point of the image based on time-of-flight, the round trip time of an artificial light signal, as provided by a laser or an LED.
When the acoustic wave propagates though the sample it may be scattered, absorbed or reflected at media interfaces. Thus, the technique registers the echo generated by the acoustic impedance (Z) contrast between two materials. Scanning acoustic microscopy works by directing focused sound from a transducer at a small point on a target object.
Nevertheless, having any decrease in the normal oxygenation of blood can affect the baby in a lot of ways, and those born with TOF can have a range of symptoms including feeding difficulty and failure to gain weight and develop normally. Babies with TOF will often experience symptoms and cyanosis in spells, which is referred to as “tet spells”.
Tetralogy of Fallot (TOF), formerly known as Steno-Fallot tetralogy, [9] is a congenital heart defect characterized by four specific cardiac defects. [4] Classically, the four defects are: [ 4 ] pulmonary stenosis , which is narrowing of the exit from the right ventricle;