Erek Erek 21 Buku Mimpi 2D 3D 4D Bergambar dan Kode Alam
2d 21The Sylvania Type 2D21 is a miniature four element thyratron with negative control characterIn this work, we introduce helical chirality into 2D COFs using confurationally stable enantiopure and racemic [5]helicenes as linkers in