Sustainable production of hydrogen by water electrolysis is a promising pathway to cope with the growing demands for renewable energy conversion and storage. The alkaline electrolysis is attracting increasing attention for more facile anodic oxygen evolution reaction (OER) but plagued by poorer kinetics in cathodic hydrogen evolution reaction (HER) even with the platinum (Pt) catalysts. With the presence of alkali metal cations and hydroxyl anions, the electrode-electrolyte (Pt-water) interface in alkaline electrolyte is far more complex than that in acidic environment. Despite considerable efforts in probing the HER kinetics in alkaline electrolyte, the exact role of these different species remains elusive and represents a topic of considerable debate. Herein, we combine electrochemical impedance spectroscopy (EIS) and a unique electrical transport spectroscopy (ETS) approach to probe and understand the fundamental role of different cations (Li + , Na + and K + ) in HER kinetics. The ETS approach provides a highly specific signaling transduction pathway to exclusively probe the surface adsorbates, while the EIS offers the critical information regarding the near surface environment in the electrical double layer (EDL). Based on these comprehensive on-surface and near-surface signals, our theoretical calculations with explicit solvation further help establish the molecular level insights into the surface adsorption properties, solvation structure, and Pt-water interface dynamics in presence of different cations and surface hydroxyl adsorbate (OH ad ). Our integrated studies

This paper is based on the results of an ethnomedicinal research work conducted in the semi-tribal mountainous area lying between District Mianwali (Punjab Province) and District Karak (Khyber Pakhtunkhwa Province), Pakistan during June 2009-July 2011. During field survey, questionnaires were used to interview the local inhabitants of the area. The ethnomedicinal data consists of 131 plant species (2 Pteridophytes, 7 Monocots, 122 Dicots) belonging to 48 families (2 Pteridophytes, 4 Monocots, 42 Dicots). The most commonly represented families were Amaranthaceae (9 spp.), Mimosaceae (8 spp.), Asteraceae and Papilionaceae (7 spp.) each; Solanaceae, Euphorbiaceae and Scrophulariaceae (6 spp.) each, followed by Boraginaceae, Brassicaceae, Lamiaceae and Polygonaceae (5 spp.) each. Plant specimens were identified, preserved and vouchers were deposited in the Plant Taxonomy Lab. of Department of Biological Sciences, University of Sargodha, Pakistan for future reference. The data collected through interviews with the local people indicates that these species are mostly used in respiratory tract infections (RTI), urinary tract infections (UTI), digestive disorders, sexual problems, skin diseases, liver ailments, wound healing, blood vomiting, malaria, piles, epilepsy, jaundice, gummosis, round worms, hepatitis etc. in the area. Due to lack of scientific approach regarding harvesting and utilization of this valuable medicinal flora, many plants are quickly going towards extinction; therefore, further work is needed to create awareness in the community conservation of the precious medicinal plants.

The pollen morphology of some species of glamorous family Convolvulaceae from arid zones of Pakistan has been evaluated. The pollen grains were acetolyzed, measured, described qualitatively, and illustrated using Light microscopy and scanning electron microscopy (SEM). The examined species have differences in shape, size, polarity and exine ornamentation, confirming the eurypalynous character. The pollen types varies from psilate to echinate and colpi to tricolporate, tetracolporate and pantocolporate. Exine ornamentation was exposed as perforate, reticulate and echinate. Spine morphology and exine sculpture are vital for the distinction of species. Pollen fertility shows that selected plants species are well-known in the Arid Zone. A taxonomic key is prepared to use these variations in the identification of species. Statistical analysis by using the Software XLSTAT exhibited that some morphological features is the main characters in identification of the taxa. These studied taxa were separated from each other using cluster Analysis. Our results constructed on MVSP ver. 3.22 software analyses that show morphological explanation; thus, the results highlight the importance of pollen morphology in the identification and characterization of species of the family convolvulacae in arid zone.

Hydrogen electrochemistry on platinum low-index single-crystal surfaces in alkaline solution.

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