"closed envelope" is a correct and usable phrase in written English.
You can use it when referring to a sealed envelope. For example: "I found an old closed envelope on the floor."
"They handed me a closed envelope with the number in it, but I never opened it.
If you use the back of a closed envelope, as Dickinson did in "A 496/497," you get three squat triangles, like faces of a flattened jewel.
In the second part, a coupled thermal and airflow simulation model is used to investigate whether the more closed envelope generates a summer overheating problem.
All the forms were placed in a closed envelope.
The decision of the study physician was stored in a coded closed envelope in order to blind the result from the results of the radiograph.
Immediately at the end of the treatment, patients completed the ODI-I, NRS and GPE questionnaires, which were placed in a closed envelope, and physical therapists recorded the results of the bridge tests.
"Apparently, closed envelopes can transmit as well," Dr. Jeffrey Koplan, the C.D.C. director, told the Senate yesterday.
Randomization was done by randomly selecting from a mixed box of closed envelopes.
The closed envelopes were shuffled before numbering, and were used for both patients with benign and malignant disease.
The survey instruments were distributed and collected in closed envelopes by an independent administrative team from the Training and Research department specifically formed for this task.
Randomization was performed by drawing of closed envelopes.
