"placed closely" is a correct and usable phrase in written English.
You can use it when describing the spatial relationship between two objects or words in a sentence. Example: The teacher placed the desks closely together to encourage collaboration among the students.
In these experiments, various wing palnforms were placed closely upstream of a tail.
The HMM was placed closely around the growth container inside the chamber of the industrial Bridgman equipment "Kronos".
Two rows of twelve bottles with algae culture were placed closely adjacent to each other in a water bath.
One is placed closely to the reactor, in the middle of the oven to control the oven temperature.
Tubes with these dimensions have a volume of approximately 60 l per m2 surface area when placed closely together, as the bottles were in the present experiments.
In order to implement more complex functionalities, as well as to design more robust dopant-induced QDs, the QDs can be formed not by individual P-donors but by a number of P-donors placed closely to each other (within 2 × r B).
Afradapis and Darwinius group closely together near the bottom of the tree in proximity to lemurs and lorises, while the primates placed most closely to anthropoids are the tarsiers and omomyids (from Seiffert et al. 2009).
This spring, Neufeld completed a preliminary study of thirty children who had been placed on closely monitored regimens of Lovenox.
This could well reflect poor design of the e-mail system, with "Reply" and "Reply to all" placed too closely together, he said.
Scanner Pro was also good, but in my tests its image quality was not as good as TurboScan's, and some of the controls were placed so closely together that I often pressed the wrong button.
On the other hand, when the cross-correlation coefficient or the standard deviation over relay-to-destination increases, the relay should be placed more closely to the destination.
