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An anatomical study was conducted in Stachys acerosa Boiss. is endemic to Zagros Chain Mountains in Iran. In the current study the samples were collected from Oshtorankuh Mountain and examined. Vegetative and reproductive organs anatomically using light microscope. The distinguishing feature of S. acerosa is the presence of sclerenchyma at the angles of the stem. Five types of trichomes - simple nonglandular uniseriate uni- and multicellular, short and long capitate glandular, and glandular peltate trichomes were found on the surface of vegetative and reproductive organs. The leaves are amphistomatic and isobilateral; and the mesophyll is composed of four-layers palisade parenchyma. Two of them present at the upper side and another two layers at lower side and in between palisade layers two-layered spongy parenchyma were existed. The present study shows that the certain anatomical features of Stachys taxa are valuable for species delimitation. Bangladesh J. Bot. 51(2): 325-334, 2022 (June)

Nitric acid vapor phase oxidation of multi-walled carbon nanotubes (MWCNTs) was proposed as a promising technique to fabricate poly styrene-co-acrylonitrile (SAN)-grafted-CNTs via atom transfer radical polymerization (ATRP). The in-situ ATRP grafting approach was successfully employed to graft polystyrene (PS), SAN and polyacrylonitrile (PAN), onto the convex surfaces of pristine MWCNTs (PCNT) and acid-functionalized MWCNTs (FCNT). Fourier transform infrared spectroscopy (FTIR), proton nuclear magnetic resonance (1H-NMR), and thermogravimetric analysis (TGA) confirmed the effectiveness of the modification via the ATRP grafting approach. The molar composition of acrylonitrile in the synthesized copolymer on the surface of CNTs for an FCNTs was calculated to be about 80% and 67.5% by 1H-NMR and TGA respectively, whereas the value is lower for PCNTs. Morphological studies showed that SAN-grafted FCNTs exhibit rougher surface morphology compared to the SAN-grafted PCNTs. Moreover, the higher diameter of the FCNTs indicated the higher polymer content, which was coated onto CNTs functionalized by vapor-phase oxidation. Therefore, the vapor phase oxidation strategy employed in this study could be utilized as a general method to prepare CNTs which can serve as an ATRP macroinitiator for the fabrication of various polymer grafted CNTs.