Design of eco-friendly antifreeze peptides as novel inhibitors of gas-hydration kinetics.

In this study, peptides designed using fragments of an antifreeze protein (AFP) from the freeze-tolerant insect Tenebrio molitor, TmAFP, were evaluated as inhibitors of clathrate hydrate formation. It was found that these peptides exhibit inhibitory effects by both direct and indirect mechanisms. The direct mechanism involves the displacement of methane molecules by hydrophobic methyl groups from threonine residues, preventing their diffusion to the hydrate surface.

Synergistic Effect of Hyperactive Antifreeze Protein on Inhibition of Gas-Hydrate Growth by Hydrophobic and Hydrophilic Groups.

Antifreeze proteins (AFPs) are biodegradable inhibitors that effectively prevent the formation of natural gas hydrates that block pipelines. In this study, molecular dynamics simulations were employed to establish a kinetic model of the hyperactive insect antifreeze protein (, AFP) and its mutants to inhibit the growth of sI natural methane hydrate. Simulations revealed that the hydrophobic and hydrophilic groups of threonine (Thr) residues at hydrate-binding sites played a synergistic role in binding hydrates.

The contribution of inner electron excitation to the electronic stopping power of palladium for protons.

The electronic stopping power of palladium (Pd) for protons is investigated based on time-dependent density functional theory combined with Ehrenfest molecular dynamics simulations. The electronic stopping power of Pd with explicitly considering inner electrons for protons is calculated and the excitation mechanism for the inner electrons of Pd is revealed. The velocity proportionality of the low-energy stopping power of Pd is reproduced.

Electronic stopping power for slow ions in the low-hardness semimetal HgTe using first-principles calculations.

The electronic stopping power for low-velocity ions (including protons, [Formula: see text]-particles, and [Formula: see text]) is investigated in a novel semimetal HgTe system, where the data are obtained with the aid of Ehrenfest dynamics combined with time-dependent density functional theory. For the light projectile ions (protons and [Formula: see text]-particles), the linear and nonlinear behaviors of electronic stopping power in three different channel directions are analyzed in detail. In the case where the projectile ion is a proton, the linear results for the threshold velocity are correlated with an indirect band gap; the direction of the electronic stopping power depends on the radial drag force, the channeling electronic density and the trapped charge.

Mixed-salt effects on the conformation of a short salt-bridge-forming α helix: a simulation study.

The structure of a single alanine-based ACE-AEAAAKEAAAKA-NH2 peptide in explicit aqueous solutions with mixed inorganic salts (NaCl and KCl) is investigated by using molecular simulations. The concentration of Na(+), c(Na(+)), varies from 0.0M to 1.

Collision dynamics of proton with formaldehyde: fragmentation and ionization.

Using time-dependent density functional theory, applied to the valence electrons and coupled non-adiabatically to molecular dynamics of the ions, we study the ionization and fragmentation of formaldehyde in collision with a proton. Four different impact energies: 35 eV, 85 eV, 135 eV, and 300 eV are chosen in order to study the energy effect in the low energy region, and ten different incident orientations at 85 eV are considered for investigating the steric effect. Fragmentation ratios, single, double, and total electron ionization cross sections are calculated.

Theoretical study on collision dynamics of H(+) + CH4 at low energies.

In this work we make an investigation on collision dynamics of H(+) + CH4 at 30 eV by using time-dependent density functional theory coupled with molecular dynamics approach. All possible reactions are presented based on 9 incident orientations. The calculated fragment intensity is in nice agreement with experimental results.

The effects of electron transfer on the energy loss of slow He²⁺, C²⁺, and C⁴⁺ ions penetrating a graphene fragment.

Electronic energy loss in the collision processes of slow ions with a graphene fragment is investigated by combining ab initio time-dependent density functional theory calculations for electrons with molecular dynamics simulations for ions in real time and real space. We study the electronic energy loss of slow He²⁺, C²⁺, and C⁴⁺ ions penetrating the graphene fragment as a function of the ion velocity, and establish the velocity-proportional energy loss for low-charged ions down to 0.1 a.

[Analysis of typical mangrove spectral reflectance characteristics].

Acquisition of mangrove spectrum properties and detecting the sensitive bands provide technology basis for inverse modeling and estimation by remote sensing for various indexes of mangrove. The typical mangroves of Guangxi Shankou Mangrove Reserve were taken for study objects, the standard spectrum curves of Bruguiera gymnorrhiza (Linn.) Savigny, Rhizophora stylosa, Kandelia candel, Avicennia marina, Aegiceras corniculatum, Spartina anglica and mudflat were gained by denoising analysis of field-measured spectrum curves acquired by ASD FieldSpec 2.

Electron-ion coupling effects on radiation damage in cubic silicon carbide.

A two-temperature model has been used to investigate the effects of electron-ion coupling on defect formation and evolution in irradiated cubic silicon carbide. By simulating 10 keV displacement cascades under identical primary knock-on atom conditions, we find that the final displacement and the kinetic energy of the primary knock-on atom decrease rapidly with increasing electron-ion coupling strength. Moreover, by analyzing the number of peak defects, atomic and electronic temperatures, it is found that a higher number of peak defects is created for intermediate coupling strength due to the electronic temperature making a contribution to the disorder.

[Spatiotemporal dynamic fuzzy evaluation of wetland environmental pollution risk in Dayang estuary of Liaoning Province, Northeast China based on remote sensing].

Based on the aerial image data of Dayang estuary in 2008, and by virtue of Analytic Hierarchy Process (AHP) , remote sensing technology, and GIS spatial analysis, a spatiotemporal evaluation was made on the comprehensive level of wetland environmental pollution risk in Dayang estuary, with the impacts of typical human activities on the dynamic variation of this comprehensive level discussed. From 1958 to 2008, the comprehensive level of the environmental pollution risk in study area presented an increasing trend. Spatially, this comprehensive level declined from land to ocean, and showed a zonal distribution.

[Changes of wetland landscape pattern in Dayang River Estuary based on high-resolution remote sensing image].

Based on the comprehensive consideration of the high resolution characteristics of remote sensing data and the current situation of land cover and land use in Dayang River Estuary wetland, a classification system with different resolutions of wetland landscape in the Estuary was established. The landscape pattern indices and landscape transition matrix were calculated by using the high resolution remote sensing data, and the dynamic changes of the landscape pattern from 1984 to 2008 were analyzed. In the study period, the wetland landscape components changed drastically.