Advance in Tribology Study of Polyelectrolyte Multilayers

This review introduced the preparation and structural characterization of polyelectrolyte multilayers in recent years and also summarized the tribology research progress of the polyelectrolyte multilayers, including tribological properties, surface adhesion characteristics, and wear resistance properties. Statistics analysis indicated that nanoparticles‐doped polyelectrolyte multilayers present better friction and wear performance than pristine polyelectrolyte multilayers. Furthermore, the in situ growth method resulted in improved structural order of nanoparticles composite molecular deposition film. In situ nanoparticles not only reduced the molecular deposition film surface adhesion force and friction force but also significantly improved the life of wear resistance. That was due to the nanoparticles that possessed a good load‐carrying capacity and reduced the mobility of the polymer‐chain segments, which can undergo reversible shear deformation. Based on this, further research direction of in situ nanoparticles molecular deposition film was proposed

Aqua­{μ-N-[3-(dimethyl­amino)­prop­yl]-N′-(2-oxidophen­yl)oxamidato(3−)}(1,10-phenanthroline)dicopper(II) nitrate

The title complex, [Cu2(C13H16N3O3)(C12H8N2)(H2O)]NO3, consists of a nitrate ion and a binuclear CuII unit in which the oxamide ligand has a cis geometry, is fully deprotonated and acts in a bidentate fashion to one CuII atom and in a tetradentate fashion to the other CuII atom. The CuII atom coordination geometries are distorted square-planar and distorted square-pyramidal. In the crystal structure, binuclear complexes and nitrate ions are connected by classical O—H⋯O and non-classical C—H⋯O hydrogen bonds into a three-dimensional framework. The alkyl chains of the anion are equally disorded over two positions

[N′-(3-Meth­oxy-2-oxidobenzyl­idene)nicotinohydrazidato]dimethyl­tin(IV)

In the title complex, [Sn(CH3)2(C14H11N3O3)], the Sn atom is in a distorted trigonal-bipyramidal coordination, with Sn—O distances of 2.138 (2) and 2.176 (2) Å. The dihedral angles between the two chelated benzene rings and the O—Sn—N group are 71.73 (9) and 83.30 (9)°

A Method to Generate and Analyze Modified Myristoylated Proteins

Covalent lipid modification of proteins is essential to their cellular localizations and functions. Engineered lipid motifs, coupled with bio-orthogonal chemistry, have been utilized to identify myristoylated or palmitoylated proteins in cells. However, whether modified proteins have similar properties as endogenous ones has not been well investigated mainly due to lack of methods to generate and analyze purified proteins. We have developed a method that utilizes metabolic interference and mass spectrometry to produce and analyze modified, myristoylated small GTPase ADP-ribosylation factor 1 (Arf1). The capacities of these recombinant proteins to bind liposomes and load and hydrolyze GTP were measured and compared with the unmodified myristoylated Arf1. The ketone-modified myristoylated Arf1 could be further labeled by fluorophore-coupled hydrazine and subsequently visualized through fluorescence imaging. This methodology provides an effective model system to characterize lipid-modified proteins with additional functions before applying them to cellular systems

Side-by-Side In(OH)3 and In2O3 Nanotubes: Synthesis and Optical Properties

A simple and mild wet-chemical approach was developed for the synthesis of one-dimensional (1D) In(OH)3 nanostructures. By calcining the 1D In(OH)3 nanocrystals in air at 250 °C, 1D In2O3 nanocrystals with the same morphology were obtained. TEM results show that both 1D In(OH)3 and 1D In2O3 are composed of uniform nanotube bundles. SAED and XRD patterns indicate that 1D In(OH)3 and 1D In2O3 nanostructures are single crystalline and possess the same bcc crystalline structure as the bulk In(OH)3 and In2O3, respectively. TGA/DTA analyses of the precursor In(OH)3 and the final product In2O3 confirm the existence of CTAB molecules, and its content is about 6%. The optical absorption band edge of 1D In2O3 exhibits an evident blueshift with respect to that of the commercial In2O3 powders, which is caused by the increasing energy gap resulted from decreasing the grain size. A relatively strong and broad purple-blue emission band centered at 440 nm was observed in the room temperature PL spectrum of 1D In2O3 nanotube bundles, which was mainly attributed to the existence of the oxygen vacancies