The phrase "a certain unit" is correct and usable in written English.
It can be used when referring to a specific but unspecified unit, often in contexts like measurements, military, or organizational structures.
Example: "In the experiment, we will be measuring the results using a certain unit of measurement that is standard in the field."
Alternatives: "a specific unit" or "an unspecified unit".
He got an assignment to a certain unit of the Signal Corps at Arlington.
The two sides acknowledge that they are snagged over what happens if there is a dispute about whether there is adequate staffing at a certain unit on a certain day.
For a certain unit, the diameter of each pod is nearly identical.
For the series connection, the Au cathode in a certain unit cell is connected to the patterned FTO layer in the adjacent unit cell.
In MFA, a certain unit of raw material fed into a system, is examined (e.g. an industry, household, region) that produces certain outputs from the system.
According to the "law of diminishing marginal utility of material resources", the amount of benefit a person gets out of a certain unit of material resources is less the more units of that material good the person already has.
Teacher B admitted she faced departmental pressure to conclude her instructional unit by a certain date because of the upcoming state-mandated student science assessment.
TOF difference is therefore typically stored as multiples of a certain minimal unit, e.g., in the Gemini TF, 25 ps units are used, which is surely fine enough considering that the TOF resolution is 500 550 ps.
For example, if a publisher knows his sales force can get $1 per thousand impressions on a certain ad unit, he might allow partners to sell it if they can get $1.25 or higher.
However, after 1949, doctors became members of a certain work unit and were fragmented.
SC describes the level of concentration of a certain map unit in the clusters.
