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Composite materials which combine the advantages of both embedded constituents have been a successful strategy for developing novel multi‐functional materials. Here, we demonstrate the synthesis of nanoscale materials of organic‐inorganic hybrid lead halide perovskites (OIH‐LHP) with enhanced optoelectronic properties and photostability by utilizing biomimetic ligand, chitosan. Notably, nanocrystals fabricated with chitosan mediated ligands exhibit an increase in photoluminescence quantum yield by 300 % and fluorescence lifetime by 1.5 times. Consequently, the lifetime distribution of the photoluminescence emission decreases to a value as low as 6 ns. More interestingly, even though chitosan is a wide band gap insulating material, its incorporation onto the perovskite NCs enhances the bulk hole mobility by at least an order of magnitude in comparison to the pristine material. With detailed spectroscopic and structural studies, we correlate these enhancements in optoelectronic parameters to the improvement in the crystal quality, phase purity, and minimized poly‐dispersity of the nanocrystals. Development of such composite materials with unprecedented optoelectronic properties and outstanding stability will contribute immensely towards high performance nanocrystal devices. [ABSTRACT FROM AUTHOR]

Post‐operative bone growth and long‐term bone adaptation around the orthopaedic implants are simulated using the mechanoregulation based tissue‐differentiation and adaptive bone remodelling algorithms, respectively. The primary objective of these algorithms was to assess biomechanical feasibility and reliability of orthopaedic implants. This article aims to offer a comprehensive review of the developments in mathematical models of tissue‐differentiation and bone adaptation and their applications in studies involving design optimization of orthopaedic implants over three decades. Despite the different mechanoregulatory models developed, existing literature confirm that none of the models can be highly regarded or completely disregarded over each other. Not much development in mathematical formulations has been observed from the current state of knowledge due to the lack of in vivo studies involving clinically relevant animal models, which further retarded the development of such models to use in translational research at a fast pace. Future investigations involving artificial intelligence (AI), soft‐computing techniques and combined tissue‐differentiation and bone‐adaptation studies involving animal subjects for model verification are needed to formulate more sophisticated mathematical models to enhance the accuracy of pre‐clinical testing of orthopaedic implants. [ABSTRACT FROM AUTHOR]

The present study deals with the design, formation, and photophysical studies on light‐harvesting inorganic‐organic nanohybrid associates comprising a less‐toxic, inorganic core‐shell QD (Cu−In−S/ZnS) and an organic S0041 dye aggregate. One of the main objectives of this study is to understand the interaction between the inorganic and organic excitonic components of the hybrid system and its implication on the photophysical response of the system. The nanohybrid associate have been obtained through the self‐assembly of S0041 dye molecules (organic exciton) onto Cu−In−S/ZnS QD (inorganic exciton). The characterization of as‐synthesized QD have been done by conventional microscopic and spectroscopic measurements. The exciton domain length for the organic dye aggregates is estimated to be 24 nm. Steady‐state absorption, emission, and time‐resolved photoluminescence (PL) intensity decay measurements have been carried out to understand the interaction mechanism between inorganic and organic excitonic components and the overall photophysical behaviour of the hybrid system. The studies have revealed that the formation of hybrid associate is electrostatically driven and thermodynamically feasible. Interestingly, steady‐state and time‐resolved PL decay measurements and their analysis have revealed that the interaction between inorganic QD and organic aggregate is mediated through dipole‐dipole Förster energy transfer (ET) mechanism and the ET efficiency is found to be as high as 95%. The present system is expected to be used in fabrication of less‐toxic nanoscale light‐harvesting system. [ABSTRACT FROM AUTHOR]

Developing a robust metal‐organic framework (MOF) which facilitates proton hopping along the pore channels is very demanding in the context of fabricating an efficient proton‐conducting membrane for fuel cells. Herein, we report the synthesis of a novel tetradentate aromatic phosphonate ligand H8L (L=tetraphenylethylene tetraphosphonic acid) based Ni‐MOF, whose crystal structure has been solved from single‐crystal X‐ray diffraction. Ni‐MOF [Ni2(H4L)(H2O)9(C2H7SO)(C2H7NCO)] displays a monoclinic crystal structure with a space group of P 21/c, a=11.887 Å, b=34.148 Å, c=11.131 Å, α=γ=90°, β=103.374°, where a nickel‐hexahydrate moiety located inside the void space of the framework through several H‐bonding interactions. Upon treatment of the Ni‐MOF in different pH media as well as solvents, the framework remained unaltered, suggesting the presence of strong H‐bonding interactions in the framework. High framework stability of Ni‐MOF bearing H‐bonding interactions motivated us to explore this metal‐organic framework material as proton‐conducting medium after external proton doping. Due to the presence of a large number of H‐bonding interactions and the presence of water molecules in the framework we have carried out the doping of organic p‐toluenesulfonic acid (PTSA) and inorganic sulphuric acid (SA) in this Ni‐MOF and observed high proton conductivity of 5.28×10−2 S cm−1 at 90 °C and 98% relative humidity for the SA‐doped material. Enhancement of proton conductivity by proton doping under humid conditions suggested a very promising feature of this Ni‐MOF. [ABSTRACT FROM AUTHOR]

Photoelectrochemical water oxidation or oxygen evolution reaction (PEC‐OER) at the semiconductor surfaces has attracted huge attention over the years as it plays key role for energetically demanding processes like fuel cells, water splitting, and rechargeable metal‐air batteries. Thus, development of sustainable, abundant and economical semiconductor nanomaterials as the catalyst for photoelectrochemical water oxidation reaction is very challenging in achieving high efficiency in the overall water splitting reaction. Herein, we report a new porous Ni−W mixed metal phosphonate material NiWPPA‐4 with open framework structure through simple hydrothermal route and its crystalline framework has been indexed into a new orthorhombic crystal with unit cell dimensions: a=14.5506 Å, b=17.6445 Å, c=20.1766 Å and α=β=γ=90°. NiWPPA‐4 has been successfully utilized for photoelectrochemical OER from moderately basic medium [1(M) KOH] under constant irradiation of 100 mWcm−1 light source. Semiconducting property together with nanoscale porosity in the Ni−W mixed metal phosphonate is responsible for photoelectrochemical OER in alkaline pH. To the best of our knowledge it is the first report on a mixed metal phosphonate material, which showed excellent catalytic activity in the photoelectrochemical OER. The onset‐potential of NiWPPA‐4 prepared over ITO coated glass was only −410 mV vs Ag/AgCl and the oxygen evolution rate is 275 μmol g−1. This study thus established efficient photoelectrochemical OER on porous mixed‐metal phosphonates and offer opportunities for the utilization of metal phosphonates as potential photocatalyst in the energy conversion processes. [ABSTRACT FROM AUTHOR]

ABSTRACT Elastomeric Chlorosulfonated polyethylene (Hypalon®) and thermoplastic Polypropylene (PP) based thermoplastic vulcanizates (TPVs) were prepared in presence of different doses of compatibilizer, maleic anhydride grafted PP (PP-g-MA) by employing dynamic vulcanization technique. The effect of incorporation in different proportions of compatibilizer on mechanical, spectral, morphological, thermal, and rheological properties of such TPVs was studied and the same were compared to that of virgin PP and amongst themselves. The mechanical analysis of the prepared TPVs exhibited significant improvements in stress at 25% modulus, ultimate tensile strength (UTS), and hardness values. FTIR studies revealed that a chemical interaction had taken place between Hypalon® and functionalized compatibilizer during the process of dynamic vulcanization which led to an enhancement of interfacial adhesion between them. The two-phase morphologies were clearly observed by scanning electron microscopic studies. The Tg values of Hypalon® was modified in the TPVs as exhibited by differential scanning calorimetric studies. TGA studies indicated the increase in thermal stability of all TPVs with respect to the elastomeric Hypalon®. Rheological properties showed that the compatibilizer reduces the melt viscosity of TPVs and thus facilitates the processibility of such TPVs. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014, 131, 40312. [ABSTRACT FROM AUTHOR]

Different thermoplastic vulcanizate (TPV) blends were prepared from elastomeric chlorosulfonated polyethylene (CSM) and thermoplastic polypropylene (PP) by employing dynamic vulcanization technique. The mechanical properties of such blends were compared in respect of their stress at 25% modulus (25%M), ultimate tensile strength (UTS), percent elongation at break, and hardness to those of pure CSM. The mechanical analysis showed substantial improvement in stress at 25%M, UTS, and hardness values with the incorporation of 15-40 parts of thermoplastic contents (PP) (per hundred parts of blend). The two-phase morphologies were clearly observed by scanning electron microscopy studies. The thermal properties were studied by differential scanning calorimetry (DSC) and thermogravimetric analysis (TGA). DSC studies showed a decreasing trend in glass transition temperature ( Tg) and TGA studies indicated the increase in thermal stability of all TPV blends with respect to the elastomeric CSM. Rheological studies showed that there is an increasing trend in shear melt viscosity of TPV blends with the increase in PP amount as the higher content of isotactic PP used in the present case increases the melt viscosity. The TPVs obtained after the rheotron studies displayed identical shear stress/strain pattern when further subjected to the same study. © 2012 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2013 [ABSTRACT FROM AUTHOR]

Polypropylene (PP) was melt blended with Vectra B-950 [a thermotropic liquid crystalline polymer (LCP)], in a single screw extruder in presence of different doses of ethylene acrylic acid (EAA) copolymer, as modifier. The effect of incorporation in different proportions of EAA at a fixed dose of 5% LCP, on mechanical, thermal, morphological, and rheological properties of such blends was studied and the same were compared with that of pure PP and amongst themselves. Mechanical analysis (tensile properties) of the prepared blends exhibited improvements in ultimate tensile strength (UTS), modulus, toughness, hardness, and impact strength of PP matrix with the incorporation of EAA. The improvement in mechanical properties is associated with the formation of LCP fibrils as evidenced by scanning electron microscopy (SEM). A strong interaction through H-bonding between the segments of Vectra B-950 and EAA was established by FTIR study. Differential scanning calorimetry (DSC) studies indicated substantial increase in melting point of the blends, and thermogravimetric analysis (TGA) showed that the thermal stability of PP was improved with the addition of LCP and EAA. Rheological properties showed that LCP and EAA drop down the melt viscosity of PP and thus facilitate processibility of blends. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2011 [ABSTRACT FROM AUTHOR]

The article presents a study which examined the synthesis of semi-1 and semi-2 interpenetrating polymer networks (IPNs) of poly(vinyl chloride) (PVC) and in situ formed poly(ethyl acrylate) (PEA). It mentioned the role of diallyl phthalate and ethylene glycol dimethacrylate in the synthesis. It found that the semi-1 IPNs showed a decrease in their tensile strength and modulus while the semi-2 IPNs exhibited a marginal increase with increasing crosslinked PEA incorporation.

The article presents a study which evaluates the effect of fiber loading and alkalization on bamboo strips' mechanical properties reinforced by polyester resin composites. It states that bamboo fiber strips composites were treated with alkali concentration in a room temperature curing system. Fourier transform infrared (FTIR) spectroscopy was also used to evaluate concentration on mechanical properties. Results show that mechanical properties superiority was achieved with 60% filler loading.

The article presents a study regarding the effect on the ethylene-methyl acrylate copolymer of the electron-beam irradiation in the presence and absence of a trimethylolpropane trimethacrylate sensitizer. It states that the samples were compared in its mechanical, thermal, and electrical properties, and that the thermal properties were determined by thermogravimetric analysis. It adds that the irradiated sample's thermal stability has increased with an increasing electron-beam dosage.

The article discusses the study of resol matrix in the presence of alkalization and fibers on the mechanical properties of bamboo. It says that bamboo is a natural fiber and used as potential reinforcement in polymer in composites. It mentions that there is a change in fiber structure due to mercerization and leads to interfacial adhesion matrix and reinforcement.

The article discusses a study which examined the synthesis and characteristics of semi1 and semi2 interpenetrating polymer networks (IPNs) of poly(vinyl chloride) (PVC) and in situ formed poly(butyl acrylate) (PBA). Both diallyl phthalate and ethylene glycol dimethacrylate were used as crosslinkers of PVC and PBA. Results of the study showed that there was a decrease in the mechanical parameters and physical properties of semi1 IPNs. It also observed a two-stage-degradation for IPN samples.

The article presents a study on the engineering properties of poly(vinyl chloride) (PVC)-poly(butyl methacrylate) (PBMA) Semi-1 and Semi-2 interpenetrating polymer networks (IPNs). The researchers used an Instron Universal Testing Machine to measure different tensile properties including the toughness, modulus and ultimate tensile strength (UTS). They found that the PVC matrix was reinforced by the crosslinked methacrylate domains present in semi-2 IPNs.

The article examines the tensile strength, elongation at break, toughness and flexural strength of bamboo strips treated with caustic solutions. According to the authors, the mechanical properties of the strips rose as the concentration of caustic soda was increased. In terms of elongation at break, the level decreased continuously as caustic soda concentration was diminished. They add that the crystal structure breakdown of the cellulose fibers and the recrystallization of the degraded chains also became apparent.