Browsing by Subject "kinetics"

Article

Addition of Electron-Rich Aromatics to Azafullerenium Carbocation. A Stepwise Electrophilic Substitution Mechanism

Vougioukalakis, G. C.; Chronakis, Nikos; Orfanopoulos, Michael (2003)

(Matrix presented) The reaction between the C59N+ carbocation and the electron-rich aromatic compounds toluene and anisole has been mechanistically studied. The measured intermolecular kinetic isotope effects are consistent ...

Article

Brownian-like kinematics of ball milling for particulate structural modeling

Doumanidis, C. C.; Kaabi, H. A. Al; Alzaabi, A. S. M.; Gunduz, I. E.; Rebholz, Claus; Doumanidis, C. C. (2016)

Ball milling motion has been previously studied through computationally expensive, off-line experimental video processing and numerical simulations by the discrete element method. This research establishes a more efficient ...

Article

Carbon dioxide storage in olivine basalts: Effect of ball milling process

Rigopoulos, Ioannis; Petallidou, Klito C.; Vasiliades, Michalis A.; Delimitis, Andréas; Ioannou, Ioannis; Efstathiou, Angelos M.; Kyratsi, Theodora (2015)

The goal of this study is to propose a cost-effective method for the optimization of the ex situ carbonation of basaltic rocks. The ball milling process was applied to a sample of olivine basalt from the Troodos ophiolite ...

Article

Charge generation in inorganic/organic photovoltaic blends

Westenhoff, S.; Hayes, Sophia C.; Greenham, N. C.; Silva, C. (2004)

We apply ultrafast spectroscopy to investigate charge generation kinetics in blends of semiconducting polymers and cadmium selenide nanocrystals with photovoltaic applications. The rate is limited by diffusion of the primary ...

Article

Kinetics of methane oxidative coupling on zinc-doped titanium oxide

Efstathiou, Angelos M.; Boudouvas, D.; Vamvuka, Despina; Verykios, Xenophon E. (1992)

A kinetic study of methane conversion to C2-hydrocarbons was conducted by cofeeding methane and oxygen at 1 bar total pressure over a series of zinc-doped TiO2 catalysts. The zinc dopant concentration was varied between 1 ...

Article

A mathematical model of the unfolded protein stress response reveals the decision mechanism for recovery, adaptation and apoptosis

Erguler, K.; Pieri, Myrtani; Constantinou-Deltas, Constantinos D. (2013)

Background: The unfolded protein response (UPR) is a major signalling cascade acting in the quality control of protein folding in the endoplasmic reticulum (ER). The cascade is known to play an accessory role in a range ...

Article

Modulating unimolecular charge transfer by exciting bridge vibrations

Lin, Z.; Lawrence, C. M.; Xiao, D.; Kireev, V. V.; Skourtis, Spiros S.; Sessler, J. L.; Beratan, David N.; Rubtsov, I. V. (2009)

(Figure Presented) Ultrafast UV-vibrational spectroscopy was used to investigate how vibrational excitation of the bridge changes photoinduced electron transfer between donor (dimethylaniline) and acceptor (anthracene) ...

Article

Multiresponsive polymer conetworks capable of responding to changes in pH, temperature, and magnetic field: Synthesis, characterization, and evaluation of their ability for controlled uptake and release of solutes

Papaphilippou, P.; Christodoulou, M.; Marinica, O. M.; Taculescu, A.; Vekas, L.; Chrissafis, K.; Krasia-Christoforou, T. (2012)

This study deals with the preparation of novel multiresponsive (magnetoresponsive, thermoresponsive and pH-responsive) nanocomposite conetworks consisting of oleic acid-coated magnetite nanoparticles (OA•Fe 3O 4), ...

Article

NMR and theoretical investigations on the structures and dynamics of octahedral bis(chelate)dichloro VIII compounds isolated by an unusual reduction of non-oxo VIV species

Rikkou, Maria P.; Manos, Manolis J.; Tolis, Evangelos I.; Sigalas, Michael P.; Kabanos, Themistoklis A.; Keramidas, Anastasios D. (2003)

Reaction of the non-oxo VIV species [VIVCl2(LOO)2] [LOO = acetylacetonate (acac-) or benzoylacetonate (bzac-)] with a chelate nitrogen-donor ligand LNN in acetonitrile leads to the reduction of VIV to VIII and the formation ...

Article

Novel mixed metal Ag(I)-Sb(III)-metallotherapeutics of the NSAIDs, aspirin and salicylic acid: Enhancement of their solubility and bioactivity by using the surfactant CTAB

Gkaniatsou, E. I.; Banti, Christina N.; Kourkoumelis, Nikolaos; Skoulika, S.; Manoli, Maria; Tasiopoulos, Anastasios J.; Hadjikakou, Sotiris K. (2015)

The already known Ag(I)-Sb(III) compound of the formula {Ag(Ph3Sb)3(NO3)} (1) and two novel mixed metal Ag(I)-Sb(III) metallotherapeutics of the formulae {Ag(Ph3Sb)3(SalH)}(2) and {Ag(Ph3Sb)3(Asp)}(3) (SalH2 = salicylic ...

Article

Observation of the equilibrium CuB-CO complex and functional implications of the transient heme a3 propionates in cytochrome ba3-CO from Thermus thermophilus. Fourier transform infrared (FTIR) and time-resolved step-scan FTIR studies

Koutsoupakis, Constantinos; Stavrakis, Stavros; Pinakoulaki, Eftychia; Soulimane, T.; Varotsis, Constantinos (2002)

We report the first evidence for the existence of the equilibrium CuB 1+-CO species of CO-bound reduced cytochrome ba3 from Thermus thermophilus at room temperature. The frequency of the C-O stretching mode of CuB 1+-CO ...

Article

The phosphoform of the regulatory subunit RII of cyclic AMP-dependent protein kinase possesses intrinsic topoisomerase activity

Constantinou, Andreas I.; Squinto, S. P.; Jungmann, R. A. (1985)

The phosphoform of the type II regulatory subunit (phospho-RII-cAMP) of cAMP-dependent protein kinase from rat liver was found to possess intrinsic topoisomerase activity towards several DNA substrates such as φX174, pBR322, ...

Article

Photosynthesis from the protein's perspective

Skourtis, Spiros S.; Beratan, David N. (2007)

Article

Physical constraints on charge transport through bacterial nanowires

Polizzi, N. F.; Skourtis, Spiros S.; Beratan, David N. (2012)

Extracellular appendages of the dissimilatory metal-reducing bacterium Shewanella oneidensis MR-1 were recently shown to sustain currents of 10 10 electrons per second over distances of 0.5 microns [El-Naggar et al., Proc. ...

Article

The selective oxidation of methane to C2-hydrocarbons over lithium-doped TiO2 catalysts

Papageorgiou, D.; Efstathiou, Angelos M.; Verykios, Xenophon E. (1994)

The oxidative coupling of methane (OCM) to C2-hydrocarbons was studied on a series of lithiumdoped titania catalysts by cofeeding methane (PCH4 = 0.5 bar) and oxygen (Po2 = 0.07-0.16 bar) at 1 bar total pressure in the ...

Article

Singlet hydrocarbon carbenes with high barriers toward isomerization: A computational investigation

Nicolaïdes, Andrew N. (2003)

A prerequisite for a stable singlet hydrocarbon carbene is the existence of high barriers toward isomerization. Four derivatives of cyclopentylidene (1-4) with rigid and varying carbon cages are examined computationally ...

Article

Spectroscopic investigation on the formation of hypochlorite by alpha radiolysis in concentrated NaCl solutions

Kelm, M.; Pashalidis, Ioannis; Kim, J. I. (1999)

The hypochlorite formation induced by alpha radiation in saline solutions is studied by UV/VIS spectroscopy. Experiments are carried out in NaCl solutions of various concentrations between 1 and 5 mol/l and with volume ...

Article

Steering electrons on moving pathways.

Beratan, David N.; Skourtis, Spiros S.; Balabin, I. A.; Balaeff, A.; Keinan, S.; Venkatramani, R.; Xiao, D. (2009)

Electron transfer (ET) reactions provide a nexus among chemistry, biochemistry, and physics. These reactions underpin the "power plants" and "power grids" of bioenergetics, and they challenge us to understand how evolution ...

Article

A structural, kinetic model of soft tissue thermomechanics

Barocas, V. Η; Stylianopoulos, T.; Aksan, A. (2008)

A structure-based kinetic model was developed to predict the thermomechanical response of collagenous soft tissues. The collagen fibril was represented as an ensemble of molecular arrays with cross-links connecting the ...

Article

Water solubility, antioxidant activity and cytochrome C binding of four families of exohedral adducts of C60 and C70

Witte, P.; Beuerle, F.; Hartnagel, U.; Lebovitz, R.; Savouchkina, A.; Sali, S.; Guldi, D.; Chronakis, Nikos; Hirsch, A. (2007)

Over the past decade, surface-modified, water soluble fullerenes have been shown by many different investigators to exhibit strong antioxidant activity against reactive oxygen species (ROS) in vitro and to protect cells ...