The phrase "activity deteriorated" is correct and usable in written English.
It can be used to describe a decline in the quality or effectiveness of a particular activity or process.
Example: "Over the course of the project, the activity deteriorated due to lack of resources and poor management."
Alternatives: "performance declined" or "process worsened".
The S.E.C.'s capacity to review corporate filings and market activity deteriorated, and, predictably, the late 1950s were marked by a resurgence of fraud, particularly on the American Stock Exchange.
However, the m-MnOx catalyst activity deteriorated at temperature above 340 °C due to a transformation of MnO2 to the less active Mn2O3 and Mn3O4 phases.
Tax revenues were hit very hard by weak economic activity, deteriorating corporate profitability, elevated and rising unemployment, markedly reduced bonus payments, Badiani said.
The impedance results clearly show that the non-annealed material possesses the highest electrocatalytic activity and that this activity deteriorates with increasing annealing temperature.
Sleep-related consolidation of declarative memories, as well as associated neurophysiological events such as slow oscillatory and spindle activity, deteriorate in the course of aging.
However, for the oxidized ternary PtRuSn catalysts where RuO2 and SnO2 coexist and cover the Pt active sites, the EOR activity deteriorates.
Automakers report double-digit percentage falls in sales; an index of manufacturing activity deteriorates; and a major injection of capital into General Electric by the billionaire investor Warren Buffett fails to buoy its shares.
At increase of the annealing temperature above 600°C, "melting" and "merging" of islands occur (Fig. 3d) and their SERS activity deteriorates.
The Rorα Cre/+ ;Lhx1 loxP/loxP mice showed normal activity rhythm for up to 3 weeks under DD, after which the activity consolidation deteriorated with no apparent ∼24 hr rhythm.
On the other hand activity has deteriorated in France, the second-largest, which scored a worryingly low 42.7.Louring over the zone's prospects are two dark clouds.
More broadly, the repricing of credit also led to significantly lower net revenue levels due to illiquidity in the markets as trading activity levels deteriorated across the spectrum of fixed income products," the company said.
