The phrase "a certain reduction" is correct and usable in written English.
It can be used when referring to a specific but unspecified decrease in quantity, size, or intensity.
Example: "The study showed a certain reduction in the levels of pollution after the new regulations were implemented."
Alternatives: "a specific decrease" or "a particular reduction".
The cathodic current might be related to a certain reduction process of γ-Fe2O3.
Also in brick buildings, they provide a certain reduction of GPR, maximum and mean touch voltages.
"When we see the economic situation, it's not the moment to create conditions that would penalize growth by a certain reduction in spending," Mr. Mer said to reporters after the ministers' meeting today in Brussels.
During initial exposure, the OCP dropped about 0.35 V and the interfacial resistance increased several times, indicating a certain reduction of the polymer and oxidation of the steel surface.
At variance with many other tumours, the aetiology and pathogenesis of colorectal cancer have been partially clarified, so that we are now in the position to take preventive measures and to design surveillance programmes which might lead to a certain reduction in incidence and mortality.
Human activities induced a certain reduction in runoff.
In the late spring, for instance, he learned that a change of sentence might be in the making for Clark, whose lawyer, it appeared, had asked the jurors who convicted him to approve a petition urging clemency; all but two of them had agreed, and Eriksson was given to understand that this augured an almost certain reduction in sentence.
A 'safe time' and 'safe UV-A dose' were defined as the minimal time or UV-A dose necessary to achieve a certain bacterial reduction.
A certain growth reduction was observed in DI treatments causing WUE (plant water use efficiency) increase, in terms of reducing competition between vegetative and reproductive growth.
While link adaptation ensures that transmission errors occur with low probability, low latency retransmissions of erroneous packets within the link layer [6] maintain reliable delivery of packets, at the expense of a certain rate reduction.
On the other hand, when the code has a fixed rate and operates in the low or moderate SNR regime, the MMSE-GDFE approach does offer a certain complexity reduction with a negligible performance loss, as the singular values of R are numerically well-behaved in general.
