The phrase "a dark zone" is correct and usable in written English.
It can be used to describe an area that is physically dark or metaphorically refers to a situation that is unclear or dangerous.
Example: "The explorers ventured into a dark zone of the cave, where no light could penetrate."
Alternatives: "a shadowy area" or "a bleak region".
Finally, the threshold we used for defining cell-surface contact could be validated by checking that the occurrence of a dark zone with subthreshold darkness was correlated with the resistance to flow-induced detachment 26 and a decrease in Brownian motion (not shown).
Dominant chemical pathways responsible for the formation of a dark zone were identified.
A dark zone of about 1200 to 1300 K was observed in which the NO concentration was at its highest.
A dark zone of about 1400 1450 K was observed in which the NO and HCN concentrations were at their highest, about 15.5 and 13.5 mol%, respectively.
Various key physiochemical processes involved in the formation of a dark zone were investigated for a broad range of propellants, including nitramine, ammonium dinitramide, and double-base propellants.
Apart from NO, important species in a dark zone are CO for double-base, HCN for nitramine, and N2O for ADN propellants.
The medial zone typically houses a narrow dark strand (Figure 3B), connecting to a darker zone inside the head (Figure 3B).
A darker zone on either side of the intestine may represent an enclosing membrane, which also is seen to enclose the stomach (Figure 3E).
These chemical species typically undergo reactions with high activation energies and their chemical-induction and flow-residence times are instrumental in explaining the existence of a dark-zone temperature plateau.
Within its length a central dark zone may represent a coelomic cavity (Figure 3I).
From CL observations, it displays as two well-separated zones: (i) a strongly perturbed central zone, appearing as a very dark zone with non-uniform distribution damage and (ii) six double arms, nearly parallel to axes separated by an angle of ∼60°, confirming the hexagonal symmetry.
