Anion Recognition by Urea Derivatives of Anthraquinone: Dihydrogen Phosphate Ion Selective Neutral Receptors

Three urea derivatives of anthraquinone were synthesized and they showed a high selectivity for dihydrogen phosphate ions.     

Ionic aggregation in random copolymers containing phosphonium ionic liquid monomers

Copolymers of n‐butyl acrylate and phosphonium ionic liquid monomers possessing various alkyl substituents and counterions were synthesized through a combination of conventional free radical copolymerization and anion exchange. Differential scanning calorimetry and dynamic mechanical analysis provided the thermal and mechanical properties of these phosphonium cation‐containing random copolymers. Factors including alkyl chain length of phosphonium substituents, counterion type, as well as ionic concentration significantly influenced the association of phosphonium cations. Phosphonium ionomers with trialkyl substituents on phosphonium cations did not display the characteristic small‐angle X‐ray scattering peak, suggesting the absence of ionic clusters. However, low q peaks in wide‐angle X‐ray diffraction was indicative of significant concentration fluctuations wherein the ionic monomeric units associated. © 2011 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2012     

Digital photoelasticity of glass: A comprehensive review

The recent advances in digital photoelasticity have made it possible to use it conveniently for the stress analysis of articles and components made of glass. Depending on the application, the retardation levels to be measured range from a few nanometres to several thousand nanometres, which necessitates different techniques and associated equipments. This paper reviews the recent advances in the photoelasticity of glass with a focus on the techniques/methods developed in the last decade. A brief introduction to the residual stress in glass is provided initially to bring out its tensorial nature. The subsequent sections are organised thematically rather than chronologically, for better readability and easy access of information.     

Low temperature hermetic laser-assisted glass frit encapsulation of soda-lime glass substrates

Room temperature and low temperature (120 °C) laser-assisted glass frit bonding of soda-lime glass substrates are accomplished in this work. The locally laser melted bonding showed hermeticity with helium leak rate of <5×10⁻⁸ atm cm³ s⁻¹, maintaining its leak rate even after standard climatic cycle tests. Small size devices were bonded at room temperature while larger areas were sealed at the process temperature of 120 °C. The sealing parameters were optimized through response surface methodology that makes the process capable for further development regardless of device size.     

Challenge and Solution of Characterizing Glass Transition Temperature for Conjugated Polymers by Differential Scanning Calorimetry

Thermomechanical properties of polymers highly depend on their glass transition temperature (T _g). Differential scanning calorimetry (DSC) is commonly used to measure T _g of polymers. However, many conjugated polymers (CPs), especially donor–acceptor CPs (D–A CPs), do not show a clear glass transition when measured by conventional DSC using simple heat and cool scan. In this work, we discuss the origin of the difficulty for measuring T _g in such type of polymers. The changes in specific heat capacity (Δc _p) at T _g were accurately probed for a series of CPs by DSC. The results showed a significant decrease in Δc _p from flexible polymer (0.28 J g^?1 K^?1 for polystyrene) to rigid CPs (10^?3 J g^?1 K^?1 for a naphthalene diimide‐based D–A CP). When a conjugation breaker unit (flexible unit) is added to the D–A CPs, we observed restoration of the Δc _p at T _g by a factor of 10, confirming that backbone rigidity reduces the Δc _p. Additionally, an increase in the crystalline fraction of the CPs further reduces Δc _p. We conclude that the difficulties of determining T _g for CPs using DSC are mainly due to rigid backbone and semicrystalline nature. We also demonstrate that physical aging can be used on DSC to help locate and confirm the glass transition for D‐A CPs with weak transition signals. © 2019 Wiley Periodicals, Inc. J. Polym. Sci., Part B: Polym. Phys. 2019 , 57, 1635–1644     

Dosimetric and kinetic characteristics of watch glass sample

This paper reports the Electron Spin Resonance (ESR) and Thermoluminescence (TL) dosimetric and kinetic characteristics of commercial watch glass. Both of the ESR and TL response of the watch glass sample yielded linear behavior in the 0.5–135 Gy gamma dose range. ESR dosimetric properties of watch glass sample like dose-rate dependence, signal reproducibility and fading behavior have also been studied in detail. Kinetic behavior and activation energy of the radiation induced free radicals responsible from the ESR spectra of watch glass sample were determined. The TL kinetic parameters such as activation energy (E), frequency factor (s), order of kinetics (b) were also calculated by applying the methods of initial rise (IR), isothermal decay (ID), variable heating rate (VHR) and de-convolution.     

A potential flower-like coating consisting of calcium-phosphate nanosheets on titanium surface

A potential calcium-phosphate fl ower-like nanocoating were coated onto the titanium surface in an easy approach. It has high surface area, low cytotoxicity as well as promising cell affi nity, which makes it a potential alternative modifi cation method for titanium surface.     

Role of compositional changes on thermal,magnetic,and mechanical properties of Fe-P-C-based amorphous alloys

This work aimed to tune the comprehensive properties of Fe-P-C-based amorphous system through investigating the role of microalloying process on the crystallization behavior,glass forming ability(GFA),soft magnetic features,and mechanical properties.Considering minor addition of elements into the system,it was found that the simultaneous microalloying of Ni and Co leads to the highest GFA,which was due to the optimization of compositional heterogeneity and creation of near-eutectic composition.Moreover,the FeCoNiCuPC amorphous alloy exhibited the best anelastic/viscoplastic behavior under the nanoindentation test,which was owing to the intensified structural fluctuations in the system.However,the improved plasticity by the extra Cu addition comes at the expense of magnetic properties,so that the saturation magnetization of this alloying system is significantly decreased compared to the FeCoPC amorphous alloy with the highest soft magnetic properties.In total,the results indicated that a combination of added elemental constitutes,i.e.,Fe69Co5Ni5Cu1P13C7 composition,provides an optimized state for the comprehensive properties in the alloying system.