Correction: Theoretical study on the mechanisms of formation of primal carbon clusters and nanoparticles in space.

Correction for 'Theoretical study on the mechanisms of formation of primal carbon clusters and nanoparticles in space' by Dobromir A. Kalchevski , , 2024, https://doi.org/10.

Theoretical study on the mechanisms of formation of primal carbon clusters and nanoparticles in space.

We present a theoretical study of assembling clusters and nanoparticles in space from primordial aggregations of unbound carbon atoms. Geometry optimization and SCC-DFTB dynamics methods are employed to predict carbon clusters, their time evolution and stability. The initial density of the aggregates is found to be of primary importance for the structure of the clusters.

Study of the Chemical Vapor Deposition of Nano-Sized Carbon Phases on {001} Silicon.

Different nano-sized phases were synthesized using chemical vapor deposition (CVD) processes. The deposition took place on {001} Si substrates at about 1150-1160 °C. The carbon source was thermally decomposed acetone (CH)CO in a main gas flow of argon.

Modification of micro-crystalline graphite and carbon black by acetone, toluene, and phenol.

The chemical interactions of two types of graphite and two types of carbon black (CB) with acetone, toluene, and phenol were studied in order to evaluate the influence of chemical treatment on the structure and morphology of the carbon phases. The experimental treatment of carbon phases was carried out at room temperature for 1 hour. The chemical and phase composition were studied by x-ray photoelectron (XP) and Raman spectroscopies, while the morphology and structure were determined by powder x-ray diffraction, as well as transmission electron microscopy techniques.

Sodium and Magnesium Ion Location at the Backbone and at the Nucleobase of RNA: Molecular Dynamics in Water Solution.

The interactions between Na or Mg ions with different parts of single-stranded RNA molecules, namely, the oxygen atoms from the phosphate groups or the guanine base, in water solution have been studied using first-principles molecular dynamics. Sodium ions were found to be much more mobile than Mg ions and readily underwent transitions between a state directly bonded to RNA oxygen atoms and a completely solvated state. The inner solvation shell of Na ions fluctuated stochastically at a femtosecond timescale coordinating on average 5 oxygen atoms for bonded Na ions and 5.

Dissolution Behavior and Varied Mesoporosity of Zeolites by NH F Etching.

The mesopores formation in zeolite crystals has long been considered to occur through the stochastic hydrolysis and removal of framework atoms. Here, we investigate the NH F etching of representative small, medium, and large pore zeolites and show that the zeolite dissolution behavior, therefore the mesopore formation probability, is dominated by zeolite architecture at both nano- and sub-nano scales. At the nano-scale, the hidden mosaics of zeolite structure predetermine the spatio-temporal dissolution of the framework, hence the size, shape, location, and orientation of the mesopores.

Computational capacity of pyramidal neurons in the cerebral cortex.

The electric activities of cortical pyramidal neurons are supported by structurally stable, morphologically complex axo-dendritic trees. Anatomical differences between axons and dendrites in regard to their length or caliber reflect the underlying functional specializations, for input or output of neural information, respectively. For a proper assessment of the computational capacity of pyramidal neurons, we have analyzed an extensive dataset of three-dimensional digital reconstructions from the NeuroMorpho.

Interaction of Na, K, Mg and Ca counter cations with RNA.

Alkaline and alkaline earth ions, namely Na+, K+, Mg2+ and Ca2+, are critical for the stability, proper folding and functioning of RNA. Moreover, those metal ions help to facilitate macromolecular interactions as well as the formation of supramolecular structures (e.g.

Hydrogen Atom Transfer from Water or Alcohols Activated by Presolvated Electrons.

High-energy irradiation of protic solvents can transiently introduce excess electrons that are implicated in a diverse range of reductive processes. Here we report the evolution of electron solvation in water and in alcohols following photodetachment from aqueous hydroxide or the corresponding alkoxides studied by two- and three-pulse femtosecond spectroscopy and ab initio molecular dynamic simulations. The experiments reveal an ultrafast recombination channel of the excess electrons.

Ab initio molecular dynamics of Na⁺ and Mg²⁺ countercations at the backbone of RNA in water solution.

The interactions between sodium or magnesium ions and phosphate groups of the RNA backbone represented as dinucleotide fragments in water solution have been studied using ab initio Born-Oppenheimer molecular dynamics. All systems have been simulated at 300 and 320 K. Sodium ions have mobility higher than that of the magnesium ions and readily change their position with respect to the phosphate groups, from directly bonded to completely solvated state, with a rough estimate of the lifetime of bonded Na(+) of about 20-30 ps.

Density functional study of hydrogen bond formation between methanol and organic molecules containing Cl, F, NH2, OH, and COOH functional groups.

Various hydrogen-bonded complexes of methanol with different proton accepting and proton donating molecules containing Cl, F, NH(2), OH, OR, and COOH functional groups have been modeled using DFT with hybrid B3LYP and M05-2X functionals. The latter functional was found to provide more accurate estimates of the structural and thermodynamic parameters of the complexes of halides, amines, and alcohols. The characteristics of these complexes are influenced not only by the principle hydrogen bond of the methanol OH with the proton acceptor heteroatom, but also by additional hydrogen bonds of a C-H moiety with methanol oxygen as a proton acceptor.