primary standard


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primary standard

[′prī‚mer·ē ′stan·dərd]
(science and technology)
A unit directly defined and established by some authority, against which all secondary standards are calibrated; for example, in analytical chemistry, reference substances or solutions of known chemical purity and concentration are used to standardize laboratory solutions prior to volumetric analysis or titration.
References in periodicals archive ?
RAWALPINDI -- Punjab government has decided to conduct rechecking of answer sheets of 20 top students in Middle and Primary standard examination through out the province including Rawalpindi.
[[theta].sub.ij]: a binary parameter, equal to 1 if [less than or equal to] [r.sub.1] minutes (primary standard), 0 otherwise.
For PM2.5, the appropriate index measures whether within recent 6 days, PM2.5 daily average concentration exceeded the primary standard not less than 6 times.
The E2 is Embraer's first civilian aircraft project that implements "Fly-By-Wire" software fully developed internally and tested with the LDRA tool suite for certification for DO-178C — the primary standard for commercial avionics software development.
Nonetheless, later courts recited the primary standard in opinions on wholly or partially tax-motivated transactions without explaining why it should apply.
This applies to rectilinear accelerometers with zero-frequency response, mainly of the strain gauge or piezoresistive type, and to primary standard and working transducers.
The first primary standard for nitrogen dioxide is 100 parts per billion by volume (ppb) measured over one hour, where the 98th percentile of 1 hour daily maximum concentrations is averaged over 3 years.
Of the 25 lakh students up to middle school in Haryana, nearly 14 lakh are primary standard students.
The values determined were consistent with calibration data obtained over two decades at the manufacturer's laboratory for eight primary standard microphones that were permanently stored there at room temperature; within the experimental errors no significant change was observed in the microphone sensitivities over the measurement period [7].
promulgates a primary standard for public health, and then sets a
When my mother graduated in the late '80s, the primary standard was to improve overall health.