-
Barlow Templeton posted an update 4 days, 11 hours ago
The sucessful grafting of highly polar polymer chains both on the surface and in the subsurface of PDMS via subsurface initiated ATRP for the improved antibiofouling performance is enabled by the diffusion of organic solvents (in a water-based binary solvent) which act as not only a “carrier” for hydrophilic monomers but also a “sweller” for the PDMS substrate.Recently, sulfonylation reactions using potassium/sodium metabisulfite as the sulfur dioxide surrogate have been developed rapidly. In most cases, the transformations go through radical processes with the insertion of sulfur dioxide under mild conditions. Additionally, transition metal catalysis is applied in the reactions for the synthesis of sulfonyl-containing compounds. Among the approaches, photoinduced conversions under visible light or ultraviolet irradiation are also involved. In this updated report, the insertion of sulfur dioxide from potassium metabisulfite or sodium metabisulfite is summarized.Since its invention invented in China, paper has been widely used in the world for quite a long time. However, some intrinsic defects servely hinder its application in some extreme conditions, such as underwater or in fire. Herein, a bio-inspired durable paper with robust fluorine-free coatings was fabricated via a two-step spray-deposition technique. It not only consisted of modified SiO2 microspheres and nanoparticles, but also contained an epoxy resin, endowing the paper with multifunctional properties. First, this bio-inspired functional paper showed excellent superhydrophobic and self-cleaning properties with a high static water contact angle (WCA) of 162.7 ± 0.5° and a low sliding angle (SA) of 5.7 ± 0.6°. Moreover, it possessed unusual repellent properties toward multiple aqueous-based liquids and heat-insulated properties. Second, this paper could be used for writing underwater and maintained satisfactory superhydrophobic performance for a long time with a WCA of 153.3 ± 1.8°. Besides, its high mechanical robustness was also experimentally confirmed in harsh working conditions, such as strong acid/alkali, boiling water, abrasion, bending, and folding. Compared with conventional paper, it is anticipated that this bio-inspired functional paper would be really competitive and demonstrate great potential in the field of underwater and fire-proof applications.The unsafe deposition process and slow deposition rate of the electrolyte layers are the main obstacles for electrochromic devices (ECDs) toward commercial application. In this work, an ECD with a structure of glass/ITO/WO3/LiF/NiO/ITO has been prepared by electron beam and resistance evaporation methods. The LiF electrolyte is deposited by resistance evaporation with the LiF particles and shows promising potential as the Li+ based electrolyte in ECDs owing to its high transparency and good ionic conductivity. The ECD shows a fast response (4.0 s for bleaching and 9.6 s for coloring), large optical transmittance modulations (∼58.9% at 625 nm, 100 s for coloring), good stability and high coloration efficiency (88.5 cm2 C-1). This work not only indicates that LiF can be used as a Li+ based electrolyte in an ECD, but also paves a new way to fast and safe preparation of ECDs with high performance.KTiOPO4 (KTP) is a classic commercial nonlinear optical (NLO) crystal, but its narrow bandgap (3.52 eV) prevents its practical application in the ultraviolet (UV) region. Many trials to widen the narrow bandgap of KTP have failed in the past few decades. A chemical cosubstitution strategy was implemented to design new members of the KTP-type family as potential UV NLO materials. First, a novel centrosymmetric KTP-type compound NH4SbFPO4·H2O with a sharply enlarged bandgap (5.01 eV) was obtained through three-site aliovalent substitution. Second, the noncentrosymmetric NH4SbF2SO4 was synthesized by the introduction of more F- anions to destroy the crystal symmetry and SO42- to replace PO43- for balancing the charge in NH4SbFPO4·H2O, which realized the transformation from a visible phosphate system to solar blind UV sulfate system for KTP-type family NLO materials. The preliminary experimental results indicated that NH4SbF2SO4 is a promising solar blind UV NLO material. The first-principles calculations revealed that the sharply enlarged bandgap resulted from the substitution of the transition metal cations with the main group metal cations and the introduction of F- anions with high electronegativity.Correction for ‘A quantum chemical study of hydrogen adsorption on carbon-supported palladium clusters’ by Lisa Warczinski et al., Phys. Chem. Poziotinib Chem. Phys., 2019, 21, 21577-21587, DOI 10.1039/c9cp04606b.The Pt-catalyzed hydrosilylation of equilibrating allylic azides is reported. The reaction provides only one out of four possible hydrosilylation products in good yields and with very high chemoselectivity (alk-1-ene vs. alk-2-ene), regioselectivity (linear vs. branched), and excellent functional group tolerance.Mesoporous carbon nanoparticles (MCNPs), with a particle size of 15-40 nm and pore size of 3-5 nm, were conveniently synthesized in ultrahigh yield (91.7 ± 1.5 wt%) by one-step carbonization of polyoxyethylene sorbitan trioleate (Tween 85) in H2SO4/H3PO4 mixed solution at a mild temperature (150 °C). The MCNPs showed particularly high dispersion stability in polyethylene glycol (PEG200) because their surfaces were abundant in long alkyl chains and ester groups. Considering that PEG200 is a kind of commonly used synthetic oil, the tribological properties of the MCNPs as a lubricant additive for PEG200 were evaluated in steel/steel contact and ball-on-plate reciprocating modes. The MCNPs exhibited the best friction-reducing and antiwear abilities when their concentration was 0.7 wt%, that is, adding 0.7 wt% MCNPs caused the friction coefficient and wear volume of PEG200 to reduce by 49.2% and 71.3%, 49.1% and 67.2%, 48.0% and 48.0%, 47.9% and 23.6%, and 44.4% and 8.1% at loads of 50, 100, 150, 200 and 250 N, respectively. The above results demonstrated that the antiwear function of MCNPs obviously reduced with increasing load despite their friction-reducing function only decaying slightly. Moreover, the performance of MCNPs was barely attenuated when the friction duration prolonged from 20 to 200 min, suggesting their long service life. Wear surface analysis implied that the MCNPs as an additive not only formed physical absorption films on the rubbing surfaces, but also showed rolling, polishing and mending effects under an appropriate load, directly accounting for their outstanding lubrication functions.