The phrase "a frequency of approximately" is correct and usable in written English.
It can be used when discussing measurements, statistics, or data that involve frequency, indicating an estimated value.
Example: "The experiment showed a frequency of approximately 50 Hz, which is within the expected range."
Alternatives: "an estimated frequency of" or "a frequency close to".
Isolated, short lasting bursts (with a duration of about 62±14 ms), reminiscent of twitch-related events in vivo, also occurred in motor zones, at a frequency of approximately 2 min−1 (5 animals, 760 bursts; Fig. 4e,h).
We have previously shown R297X to be the most common mutation in a cohort of Dutch and Australian patients, occurring at a frequency of approximately 12.5%.
Domestic microwave oven emit photons with a frequency of approximately 2.45 GHz, meaning their electric field changes polarity 2.45 billion times a second, causing these polar molecules to rapidly bump off each other as they try to align to the rapidly changing field.
Such a setup was used by Ferenc Krausz at the Technical University of Vienna and co-workers to observe directly the time variation of the electric field in a light wave at a frequency of approximately 1015 Hz.
The MR data were divided into a series of 268 images with a frequency of approximately 1 Hz.
The C677T allele (rs1801133), a common variant of the MTHFR gene has a frequency of approximately 23 41 % in the Caucasian population [7].
We found four patterns in the frequency-dependent behavior of reflection coefficients: (a) a nearly flat spectrum (little variation), (b) a significant hole at a frequency of approximately 1 or 3 Hz, (c) a peak at a frequency of approximately 2 or 3 Hz, and (d) the existence of a hole and a peak.
EGFR over-expression is one of the most common genetic alteration in primary glioblastoma multiforme (GBM) with a frequency of approximately 40% [1] [4 ]
Similarly, flowgrams of sample 13a (5% tumor cells) revealed a 12-bp deL747_A750del_T751Pel_T751P) at a frequency of approximately 8% of 658 reads (Table 1).
Each point on the body undergoes a sinusoidal lateral displacement with amplitudes of about half the body length and a frequency of approximately 3 Hz.
In order to reduce the PNP elephant population growth rate to zero, this type and level of mortality event would be required at a frequency of approximately three to four years.
