• TEL: 0086-21-58386256

primary cesium frequency and time standardapparatus for producing sheeting

  • Imaging Equipment and Quality Control (RAD 473) Quiz 1 ...

    -more primary radiation is produced in a shorter period of time which reduces the change of motion -The photons that are produced have higher average frequency as compared to single phase -We will not have "pulses" of primary radiation being produced - it will be a more of a constant puled production …[...]

  • JP2015112841A - Method for producing resin molding, and ...

    PROBLEM TO BE SOLVED: To provide a method for producing a resin molding, in which deformation of the resin molding having a transparent resin molding part and an opaque resin molding part and the internal stress or strain of the transparent resin molding part can be made smaller, and to provide the resin molding obtained by the method for producing the resin molding.SOLUTION: In the method for ...[...]

  • Progress in building NRC's cesium fountain clock | Request PDF

    Progress in building NRC's cesium fountain clock ... of a cesium fountain atomic clock at the Frequency and Time Group of the National Research Council (NRC) Canada. ... of NRC's cesium fountain ...[...]

  • Conducting - Wikipedia

    Conducting is the art of directing a musical performance, such as an orchestral or choral concert.It has been defined as "the art of directing the simultaneous performance of several players or singers by the use of gesture." The primary duties of the conductor are to interpret the score in a way which reflects the specific indications in that score, set the tempo, ensure correct entries …[...]

  • Cobalt-60 - an overview | ScienceDirect Topics

    P.B. Roberts, in Encyclopedia of Food Sciences and Nutrition (Second Edition), 2003. Source. The commonly used sources of radiation are cobalt-60, a radioactive element emitting γ-rays, or an accelerator producing a beam of electrons.. Cobalt-60 is produced by neutron bombardment of stable cobalt in a nuclear reactor.[...]

  • Syncworks - Sync and Time Products, Parts, Accessories and ...

    Microsemi's GPS Primary Reference Sources (PRSs), also known as "master clocks," provide the highest level of time and/or frequency accuracy. PRSs are categorized by the source that is used to derive their timing outputs: GPS (Global Positioning System), Cesium (atomic clock), or Packet PRS (IEEE 1588 PTP).[...]

  • Caesium standard - Wikipedia

    The caesium standard is a primary frequency standard in which the photon absorption by transitions between the two hyperfine ground states of caesium-133 atoms are used to control the output frequency. The first caesium clock was built by Louis Essen in 1955 at the National Physical Laboratory in the UK. and promoted worldwide by Gernot M. R. Winkler of the USNO.[...]

  • Radio News Information Sheets, March 1930 Radio News - RF Cafe

    Radio News magazine used to publish Information Sheets each month that readers could easily cut out and insert into a notebook as a handy reference. For example, one Information Sheet presents basic information on the current-producing color sensitivities of common elements like cesium, rubidium, and potassium, along with that of the human eye for comparison.[...]

  • Enhanced Primary Reference Time Clock - eeDesignIt.com

    operational advantages, as one of the cesium clocks can be removed from service while the system is in operation without any performance degradation. • TimeScale The TimeSource ePRTC solution generates time by producing its own independent autonomous TimeScale. The TimeScale provides time, phase, and frequency that[...]

  • FTS 4060 Cesium Frequency Standard - PRC68.com

    A perfect oscillator would not change frequency with time, power input, temperature, etc., but you can't get that one. The measure of how the frequency changes with running time is called aging. The specification on the HP (Agilent) 5071A Cesium standard ($50k) is less than 1E-14 per day. .[...]

  • Agilent 5071A Primary Frequency Standard Unsurpassed ...

    The 5071A primary frequency stan-dard has the accuracy and stability you need for both laboratory and field applications. A stability specifi-cation for 30-day averaging time means the 5071A will keep extremely predictible time and phase for long periods. Further, the 5071A can be used for long-term averaging of noisy signals such as GPS.[...]

  • The information questionnaire packet contains a list of ...

    Figure 3-11 illustrates the test configuration that can be used to calculate the synchronization accuracy of a DS1 (1.544 /s) signal, by comparing its extracted timing signal against, preferably, a local cesium primary frequency standard (other appropriate high-accuracy primary frequency standards may be …[...]

  • Cesium - an overview | ScienceDirect Topics

    The frequency offset is typically near 1 × 10 −12 after a warm-up period of 30 minutes. The current state-of-the-art in cesium technology is the cesium fountain oscillator, named after its fountain-like movement of cesium atoms. A cesium fountain named NIST-F1 serves as the primary standard of time and frequency for the United States.[...]

  • 131 Nuclide Safety Data Sheet 131I Iodine-131

    with thick plastic sheeting (i.e., painter's drop cloth), periodically wipe it clean and replace it if torn. 3. Label each unattended radioactive material container with the radioactive symbol, isotope, activity, and, except for waste, the ICN [inventory control number]. Place containers too small for such labels in larger labeled containers. 4.[...]

  • Telecom Primary Reference Sources - Syncworks

    Telecom Primary Reference Sources. ... Using an innovative approach to "generate time" by producing its own timescale which is driven by high performance Cesium frequency standards and aligned with GNSS time, the TimeSource ePRTC delivers an autonomous, secure and fault tolerant reference for time, phase and frequency synchronization. ...[...]

  • Cesium - definition of cesium by The Free Dictionary

    Define cesium. cesium synonyms, cesium pronunciation, cesium translation, English dictionary definition of cesium. ... but it can be used in nuclear weapon production as well. ... To track time, a cesium clock exploits the absorption of microwaves by a cloud of cesium atoms (SN: 9/4/04, p.[...]

  • 5071A | Microsemi

    Thanks to a stability specification for 30-day averaging time, the 5071A can keep extremely predictable time and phase for long periods. Combined with a GPS timing receiver the 5071A primary frequency standard can produce a highly robust, inexpensive, and redundant frequency and time system. Key Features Frequency accuracy to 5 x 10-13[...]

  • Enhanced Primary Reference Time Clock - Microsemi

    G.8272.1 standard for an enhanced primary reference time clock. The TimeSource ePRTC contains a single unit module ... The TimeSource ePRTC solution generates time by producing its own independent autonomous TimeScale. The TimeScale provides time, phase, and frequency that ... time, while the cesium clocks and GNSS help maintain the[...]

  • Budget of Uncertainties in the Cesium Frequency Frame of ...

    Over the last several years we have made many improvements to NIST-F1 (a laser-cooled cesium fountain primary frequency standard) resulting in …[...]

  • Atomic clock - Wikipedia

    An atomic clock is a clock device that uses a hyperfine transition frequency in the microwave, or electron transition frequency in the optical, or ultraviolet region of the electromagnetic spectrum of atoms as a frequency standard for its timekeeping element. Atomic clocks are the most accurate time and frequency standards known, and are used as primary standards for international time ...[...]

  • Caesium - Element information, properties and uses ...

    One of its most important uses is in the 'caesium clock' (atomic clock). These clocks are a vital part of the internetand mobile phone networks, as well as Global Positioning System (GPS) satellites. They give the standard measure of time: the electron resonance frequency of the caesium atom is 9,192,631,770 cycles per second.[...]

  • Comparing LORAN Timing Capability to Industrial Requirements

    Interpreting industrial requirements for frequency and time accuracy ... One, of course, is a cesium oscillator, which is a primary standard of frequency. The others are disciplined oscillators, where the periodic ... ADEV numbers for given averaging times are commonly found on oscillator data sheets, and can be confused with accuracy numbers.[...]

  • Lead definition and meaning | Collins English Dictionary

    The leading goal scorers should in theory save arguments. The Sun (2012) Your gift for talking to people could lead to a job on the radio. The Sun (2011) Yet it may also lead to the outcome to which he referred six years ago. Times, Sunday Times (2012) Town halls take their lead from central government. The Sun (2008) So how can any of us as emotional beings find a way to lead?[...]

  • Principles of Exposure- FINAL REVIEW (Tests 1-5, 7 &8 ...

    Start studying Principles of Exposure- FINAL REVIEW (Tests 1-5, 7 &8). Learn vocabulary, terms, and more with flashcards, games, and other study tools. ... Long exposure time, unnecessary exposure, and the need to repeat the image. ... And Ionization chamber consist of two sheets of metal between which is found.[...]

  • ESon E hEhEE - apps.dtic.mil

    The current production model of the Cesium Beam Standard is Model FE-5440A which is presently used in the 616A program and other airborne, shipboard, and ground support systems. The frequency and time signals *produced by the Cesium Standard are extremely accurate with tolerances for accuracy and stability being on the order of several parts ...[...]

  • Stopwatch and Timer Calibrations (2009 edition) N I S T r ...

    v Stopwatch and Timer Calibrations The SI defines the second based on a property of the cesium atom, and for this reason cesium oscillators are regarded as primary standards for both time interval and frequency. A second is defined as the time interval required for 9 192 631 770 transitions between two energy states of the cesium atom to take ...[...]

  • 15230-101 | Microsemi

    System Clocks & Frequency References 8040C and 8040CLN Telecom Primary Reference Sources Cesium Clock and Frequency References Active Hydrogen Maser Phase Noise and Allan Deviation Testers Mature Timing & Synchronization GPS Disciplined Oscillators (GPSDO) Clock Management[...]

  • Use frequency in a sentence | frequency sentence examples

    Where, as in private herbaria, the specimens are not liable to be handled with great frequency, a stitch here and there round the stem, tied at the back of the sheet, or slips of paper passed over the stem through two slits in the sheet and attached with gum to its back, or simply strips of gummed paper laid across the stem, may be resorted to.[...]

  • a+ cr - NIST

    Time and Frequency Division National Institute of Standards and Technology 325 Broadway Boulder, Colorado 80303 Abstract Our laboratory based cold atom source experiment is shown in Figure 1. The system consists of a vacuum The PARCS (Primary Atomic Reference Clock in chamber and accompanying lasers and optics. The[...]

  • Caesium-137 - Wikipedia

    Caesium-137 reacts with water, producing a water-soluble compound (caesium hydroxide). The biological behavior of caesium is similar to that of potassium and rubidium. After entering the body, caesium gets more or less uniformly distributed throughout the body, with the highest concentrations in soft tissue.[...]