Anodizing of iron-based alloys: fundamentals, recent progress, and applications.

This review aims to comprehensively and systematically analyze the anodic oxidation process to form nanostructured oxide films on the surface of the most technologically relevant Fe-based alloys and steels. A special emphasis is put on detailed analysis of the mechanisms of the anodic formation of Fe-based nanostructured materials. The effect of anodizing parameters including the type of Fe-alloy, electrolyte composition, potential/current regimes, as well as various post-treatment procedures (including annealing treatment) on the growth, morphology, composition, and properties of the resulting oxide films is discussed in detail.

NO Decomposition on Singly and Doubly (K and Li)-Doped CoO Nanocubes─Establishing Key Factors Governing Redox Behavior of Catalysts.

The intimate mechanism of NO decomposition on bare and redox-tuned CoO nanocubes (achieved by single (Li or K) and double (Li and K) doping) was elucidated. The catalysts synthesized by the hydrothermal method were characterized by X-ray electron absorption fine structure measurements, X-ray diffraction, Raman spectroscopy, scanning electron microscopy, transmission electron microscopy, and Kelvin Probe techniques. TPSR and steady-state isothermal catalytic tests reveal that the NO turnover frequencies are critically sensitive to the work function of the catalysts, adjusted purposely by doping.

Influence of Fluorine Substitution on Nonbonding Interactions in Selected Para-Halogeno Anilines.

A series of 4-halogeno aniline derivatives was studied employing combined theoretical and experimental methods (i. e. crystal structure analysis and vibrational spectroscopies).

How can fluorine directly and indirectly affect the hydrogen bonding in molecular systems? - A case study for monofluoroanilines.

Hydrogen bonds (HBs) directly engaging fluorine has been extensively studied, but the indirect effect of fluorine on adjacent donors and acceptors is poorly understood and still difficult to predict. The indirect and direct effect of the fluorination of aniline on HB patterns observed in monofluoroanilines was studied via experimental (vibrational spectroscopy and crystal structure analysis) and theoretical (ab initio molecular dynamics and electrostatic surface potential) methods. It was found that a fluorine substituent decreases the strength and frequency of N-H⋯N HBs and, at the same time, increases the acidity of CH protons, enhancing the competitiveness of weaker interactions.

In Vivo Magnetic Resonance Imaging-Based Detection of Heterogeneous Endothelial Response in Thoracic and Abdominal Aorta to Short-Term High-Fat Diet Ascribed to Differences in Perivascular Adipose Tissue in Mice.

Background Long-term feeding with a high-fat diet (HFD) induces endothelial dysfunction in mice, but early HFD-induced effects on endothelium have not been well characterized. Methods and Results Using an magnetic resonance imaging-based methodology that allows characterization of endothelial function in vivo, we demonstrated that short-term (2 weeks) feeding with a HFD to mice or to mice resulted in the impairment of acetylcholine-induced response in the abdominal aorta (AA), whereas, in the thoracic aorta (TA), the acetylcholine-induced response was largely preserved. Similarly, HFD resulted in arterial stiffness in the AA, but not in the TA.

Electron Delocalization in Planar Metallacycles: Hückel or Möbius Aromatic?

In this work the relationship between the formal number of π-electrons, d-orbital conjugation topology, π-electron delocalization and aromaticity in d-block metallacycles is investigated in the context of recent findings concerning the correlation of π-HOMO topology and the magnetic aromaticity indices in these species. It is demonstrated that for π-electron rich d-metallacycles the direct link between aromaticity, the number of π-electrons and the frontier π-orbital topology does not strictly hold and for such systems it is very difficult to unambiguously associate their aromaticity with the "4+2" (Hückel) and "4" (Möbius) rules. It is also shown that the recently proposed electron density of delocalized bonds (EDDB) method can successfully be used not only to quantify and visualize aromaticity in such difficult cases, but also - in contrast to magnetic aromaticity descriptors - to provide a great deal of information on the real role of d-orbitals in metallacycles without the ambiguity of bookkeeping of electrons in the π-subsystem of the molecular ring.

Surface modification of nanoporous anodic titanium dioxide layers for drug delivery systems and enhanced SAOS-2 cell response.

Nowadays, titanium and its alloys are the most commonly used implantable materials. The surface topography and chemistry of titanium-based implants are responsible for osseointegration. One of the methods to improve biocompatibility of Ti implants is a modification with sodium hydroxide (NaOH) or 3-aminopropyltriethoxysilane (APTES).

Organocatalytic Synthesis of Higher-Carbon Sugars: Efficient Protocol for the Synthesis of Natural Sedoheptulose and d-Glycero-l-galacto-oct-2-ulose.

Herein we report a short and efficient protocol for the synthesis of naturally occurring higher-carbon sugars-sedoheptulose (d-altro-hept-2-ulose) and d-glycero-l-galacto-oct-2-ulose-from readily available sugar aldehydes and dihydroxyacetone (DHA). The key step includes a diastereoselective organocatalytic syn-selective aldol reaction of DHA with d-erythrose and d-xylose, respectively. The methodology presented can be expanded to the synthesis of various higher sugars by means of syn-selective carbon-carbon-bond-forming aldol reactions promoted by primary-based organocatalysts.

Imidazolidine-4-one derivatives in the search for novel chemosensitizers of Staphylococcus aureus MRSA: synthesis, biological evaluation and molecular modeling studies.

A series of amine derivatives of 5-aromatic imidazolidine-4-ones (7-19), representing three subgroups: piperazine derivatives of 5-arylideneimidazolones (7-13), piperazine derivatives of 5-arylideneimidazolidine-2,4-dione (14-16) and primary amines of 5-naphthyl-5-methylimidazolidine-2,4-diones (17-19), was evaluated for their ability to improve antibiotics effectiveness in two strains of Gram-positive Staphylococcus aureus: ATCC 25923 (a reference strain) and MRSA (methicillin resistant S. aureus) HEMSA 5 (a resistant clinical isolate). The latter compounds (17-19) were obtained by 4-step synthesis using Bucherer-Bergs condensation, two-phase bromoalkylation and Gabriel reactions.

An integrated photocatalytic/enzymatic system for the reduction of CO2 to methanol in bioglycerol-water.

A hybrid enzymatic/photocatalytic approach for the conversion of CO2 into methanol is described. For the approach discussed here, the production of one mol of CH3OH from CO2 requires three enzymes and the consumption of three mol of NADH. Regeneration of the cofactor NADH from NAD(+) was achieved by using visible-light-active, heterogeneous, TiO2-based photocatalysts.

Structure of two crystal forms of sheep β-lactoglobulin with EF-loop in closed conformation.

Ovine β-lactoglobulin has been isolated from whey fraction of sheep milk and crystallized. The high-resolution structures of two crystal forms (triclinic and trigonal) obtained at pH 7.0 have been determined revealing that ovine protein, similarly to its bovine analog, is dimeric.

Inhibition of jack bean urease by tetrachloro-o-benzoquinone and tetrachloro-p-benzoquinone.

Tetrachloro-o-benzoquinone (TCoBQ) and tetrachloro-p-benzoquinone (TCpBQ) were studied as inhibitors of jack bean urease in 20 mM phosphate buffer, pH 7.0, 1 mM EDTA, 25 degrees C. The mechanisms of inhibition were evaluated by analysis of the progress curves obtained with two procedures: the reaction initiated by addition of the enzyme and the reaction initiated by addition of the substrate after preincubation of the enzyme with the inhibitor.