The phrase "a small variation to" is correct and usable in written English.
It can be used when discussing a minor change or adjustment made to something, such as a plan, design, or process.
Example: "We made a small variation to the original design to improve its functionality."
Alternatives: "a slight modification to" or "a minor adjustment to".
The current understanding of particle physics, called the standard model, dictates that nowadays the number of baryons is nearly constant, with only a small variation due to quantum mechanical tunneling.
The biological replicates used in this study showed a small variation compared to the experimentally induced variation except for the tunicamycin study where the experimentally induced variation was small.
One donor showed a small variation, where due to large variability within the population, the upregulation of PPARG to adipogenic induction was not statistically significant (Donor E, Fig. 4E).
Additionally, C. albicans isolates might undergo microevolution, which means that the same isolate can undergo a small variation in its genome to adapt to some situations such as resistance to antifungal drugs.
In calculating the best fit flux values from experimental data, a small variation was introduced to reduce the number of variables and remove constraints.
The series having two methylene groups in the chain spacer (4a k), showing a small variation in affinity, revealed to be somewhat insensitive to ring substitution.
Only when there is a small variation is it possible to extrapolate the effect of therapy achieved by one therapist to his or her colleagues.
Although most of the experimental tests were conducted in smooth flow at zero angle of attack, the paper also discusses the sensitivity of the results to a small variation of the mean flow incidence and to the presence of a low-intensity free-stream turbulence.
This is due to a small variation of thickness along the surface due to the system geometry imposed on the equipment, generating poor uniformity of the applied current.
The high sensitivity of [PpIX 634]η 634 to a small variation of the ratio 620/634 is due to the fact that η 620 « η 634 [ 9].
