Correction to: Technical principles of atmospheric carbon dioxide reduction and conversion: economic considerations for some developing countries

Clean Technologies and Environmental Policy -     

Synthesis and properties of photosensitive poly(urethane‐acrylate) containing anil groups with application in the chemosensors area

Some aspects of the enol‐imine to keto‐enamine photoisomerism and fluorescent behavior of the new monomer with urethane and anil units in its structure, namely, methacryloyloxyethyl‐2‐carbamoyloxy(m‐methyl, o‐hydroxybenziliden)aniline (UAN), were studied comparatively with the corresponding copolymer poly (methacryloyloxyethyl‐2‐carbamoyloxy(m‐methyl, o‐hydroxybenziliden)aniline)‐co‐methyl methacrylate) (COP‐UAN). The structure, thermal properties, and morphology of the anil compounds were investigated by Fourier transform infrared, proton nuclear magnetic resonance, fluorescence spectroscopies, UV spectrophotometry, thermogravimetric analysis, differential scanning calorimetry, and atomic force microscopy. The photochromic behavior of salicylideneanil units was investigated by UV/laser irradiation, and an inspection of their photophysical properties suggested that such structures could function as fluorescent chemosensors for some transition metals, a fluorescence quenching in the presence of different metal cations (Fe³⁺, Fe²⁺, Cu²⁺, and Ni²⁺) being evidenced. The direct observation of an enhancement in the fluorescence emission caused of the presence of Zn²⁺ (solution) or Fe²⁺, Cu²⁺, and Zn²⁺ (thin film) would be rather suitable for the production of turn‐on fluorescent chemosensors. POLYM. ENG. SCI., 2011. © 2011 Society of Plastics Engineers     

The investigation of fly ash based asphalt binders using atomic force microscope

Atomic Force Microscope (AFM) is a relatively new technique for investigation of construction materials. In this study AFM was used to investigate the interaction of asphalt binder with fly ash. Fly ash is a coal combustion byproduct of electric power utilities having pozzolanic properties and commonly used in Portland cement concrete. In this study, an investigation was made by using different types of fly ash with two types of asphalt binders such as PG 58-28 and PG 64-28. Asphalt microstructure is divided into four subgroups such as Saturates, Aromatics, Resins and Asphaltenes (SARA). These four phases can be distinguished by the atomic force microscope. The interaction of these phases affected by introducing fly-ash was investigated and correlation with rheological properties was observed.     

Transformation of coherence and of the spectrum of light by a moving diffuser

Abstract

Effects of a diffuser on the spectral degree of coherence and on the spectrum of light produced by transmitting light through the diffuser are described. Both stationary and uniformly moving diffusers are considered and the analysis applies to dielectric as well as to absorbing diffusers. The results are illustrated by numerical examples.     

Coherence of two interfering beams modulated by a uniformly moving diffuser

Abstract

Coherence properties are discussed of light which emerges from two pinholes after it has passed through a moving diffuser. The results are used to show how the correlation function of the heights of the diffuser surface and the speed with which the diffuser is moving may be determined from simple interference experiments.     

Wetting and pressureless infiltration in the CuTi/Al2O3 system under poor vacuum

Work is aimed at preparation of Cu/Al₂O₃ composite by pressureless metal infiltration of porous alumina with simple vacuum equipment. Improvement of wetting by addition of Ti to Cu is investigated in sessile drop tests with various geometrical configurations in vacuum of 1–10 Pa. The results showed that a pre-alloyed Cu did not wet alumina substrate while stacked Cu and Ti blocks did, even though the latter had the same nominal alloy content (Ti: 10 wt%). This result had been proved by a following pressureless infiltration test, i.e. a CuTi/Al₂O₃ composite was formed with stacked Cu and Ti blocks at 1300 °C. Wettability, interfacial chemistry and microstructure were discussed with the aid of SEM and EDAX analysis in the paper. It was suggested that the initial reactant, which benefits the wettability, could be evolved to the one with a higher O:Ti ratio due to poor vacuum condition, higher temperature and longer holding time.     

Effect of cinnamate comonomers on the dental formulation properties

This study reports the synthesis and characterization of two urethane dimethacrylates containing poly(ethylene oxide) or poly(propylene oxide) segment and cinnamate pendant moieties to be formulated in dental resin composites. ¹H NMR, ¹³C NMR, and Fourier transform infrared spectroscopies, gel permeation chromatography, electrospray ionization‐mass spectroscopy, and thermogravimetric measurements confirmed their structure, whereas the photopolymerization evolution of oligodimethacrylates relating to a low–molecular‐weight dicinnamate methacrylate under ultraviolet irradiation was investigated by photo‐differential scanning calorimeter, monitoring the degree of conversion (DC) and polymerization rate. The photopolymerization results reveal that the investigated derivatives display a good photoreactivity (DC: ～ 70%) during the formation of crosslinked polymers, the DC depending especially on the sample viscosity. The polymerization shrinkage for several mixtures including the urethane oligocinnamates (20 wt %) and diglycidyl methacrylate of bisphenol A/triethyleneglycol dimethacrylate system in the absence of filler was determined, the obtained values being in the range of 6.1–8.2 vol %. For few cured specimens incorporating quartz filler (75 wt %), water sorption/solubility, contact angle, and mechanical parameters were measured to establish if such monomers could be of interest in dentistry. © 2012 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2013