The Montreal Protocol on
Substances that Deplete the Ozone Layer (a
protocol to the Vienna Convention for the
Protection of the Ozone Layer) is all
international treaty designed to protect the
Ozone layer by phasing out the production of
numerous substances believed to be responsible
for ozone depletion. The treaty was opened for
signature on September 16. 1987, and entered
into force on January 1, 1989, followed by a first
meeting in Helsinki. May 1989.
ভাষা ও ভাষার উৎপত্তি
Plasma Physics (প্লাজমা পদার্থবিদ্যা)
Laser (লেজার)
Quantum materials (কোয়ান্টাম উপকরণ)
Particle physics (কণা পদার্থবিজ্ঞান)
Optics (অপটিক্স এবং ফোটোনিক্স)