Surface reactive phases of soils and aquifers, comprised of phyllosilicate and metal oxohydroxide minerals along with humic substances, play a critical role in the regulation of contaminant fate and transport. Much of our knowledge concerning contaminant-mineral interactions at the molecular level, however, is derived from extensive experimentation on model mineral systems. Although these inves...

Surface active sites of crystals often govern their relevant surface chemistry, yet to monitor them in situ in real atmosphere remains a challenge. Using surface-specific sum-frequency spectroscopy, we identified the surface phonon mode associated with the active sites of undercoordinated titanium ions and conjoint oxygen vacancies, and used it to monitor them on anatase (TiO2) (101) under ambi...

Some aspects of the reaction mechanisms in multistep selective (amm)oxidation reactions over oxide surfaces are discussed evidencing some of the challenges for surface science and theory in describing these reactions, and for applied catalysis in order to have a more in deep identification of the key factors governing surface reactivity and which may be used to improve catalytic performances. I...

The alteration of two trioctahedral micas, biotite and phlogopite, was investigated at the meso, micro, nanoscale using three complementary microscopy techniques to better understand mica surface reactivity. In situ ex experiments were performed monitor mineral interface during dissolution in acidic solutions (nitric oxalic acid, pH ∼ 1–2), over a temperature range 25–100°C. inorganic acid used...

The current investigation demonstrates that it is possible to molecularly design supported niobium oxide catalysts with the assistance of molecular characterization methods such as Raman spectroscopy. The formation and location of the surface niobium oxide species are controlled by the surface hydroxyl chemistry, and the surface niobium oxide species are located in the outermost layer of the ca...

this study was conducted to characterize the reactivity of carbonates in the surface horizons of 20 soils (entisols and aridisols) from central region of iran. the samples were analyzed for calcium carbonate equivalent (cce), active calcium carbonate equivalent (acce), non-active calcium carbonate equivalent (n.acce), carbonate mineralogy and surface area of carbonates (ssa) through n2 adsorpti...

Sequential reactivity is creating various kinds of macromolecular compounds with distinct prochirality using an on-surface synthesis approach.

In this Letter we show that sequences of adsorbate-induced shifts of surface core level (SCL) x-ray photoelectron spectra contain profound information on surface changes of electronic structure and reactivity. Energy shifts and intensity changes of time-lapsed spectral components follow simple rules, from which adsorption sites are directly determined. Theoretical calculations rationalize the r...

Gaining insight into Pd/C catalytic systems aimed at locating reactive centers on carbon surfaces, revealing their properties and estimating the number of reactive centers presents a challenging problem. In the present study state-of-the-art experimental techniques involving ultra high resolution SEM/STEM microscopy (1 Å resolution), high brilliance X-ray absorption spectroscopy and theoretical...

a b s t r a c tintroduction: craving to methamphetamine is a significant health concern and exposure to methamphetamine cues in laboratory can induce craving. in this study, a task designing procedure for evaluating methamphetamine cue-induced craving in laboratory conditions is examined. methods: first a series of visual cues which could induce craving was identified by 5 discussion sessions b...