Comprehensive Understanding of Urban Water Supply Management: Towards Sustainable Water-socio-economic-health-environment Nexus

Water Resources Management - The majority of the cities across the developing countries have saddled water supply and quality management issues. Unfortunately, even cities with adequate water...     

Local support-based partition algorithm for frequent pattern mining

Pattern Analysis and Applications - Frequent pattern (itemset) mining is one of the established approaches for knowledge discovery. Minimizing the number of database scans (I/O overhead) is a...     

Stimuli Responsive Self-Assembly of 3-(Octyloxy)-3-Oxopropyl Acrylate-Co-Acrylic Acid Polymer in Aqueous Media

A novel copolymer based on 3-(alkyloxy)-3-oxopropyl acrylate and acrylic acid was synthesized and characterized. Surface tension and fluorescence probe techniques (using N-phenyl-1-naphthylamine as a probe) were employed to evaluate the surface properties of the amphiphilic copolymer. The copolymer was found to reduce the surface tension of water to 40–46 mN/m depending on the pH of the medium. The critical aggregation concentration of the copolymer determined by surface tension measurements was found to be 0.28 mg/ml at pH 4, 1.13 mg/ml at pH 8, and 1.44 mg/ml at pH 10, very close to those obtained by steady state fluorescence probe techniques (0.21, 1.13 and 1.48 mg/ml, respectively, at pH 4, 8, and 10). The pH-induced structural transitions of the copolymer were also studied using steady state fluorescence with pyrene and 1,6-diphenyl-1,3,5-hexatriene as probes, dynamic light scattering and transmission electron microscopy. The protonation of pendant carboxylate groups at acidic pH makes the aggregate compact and rigid. Conversely, ionization of the carboxylate groups under alkaline conditions resulted in larger aggregates.     

UV–LED driven photodegradation of organic dye and antibiotic using strontium titanate nanostructures

Journal of Materials Science: Materials in Electronics - In the present study, SrTiO3 (strontium titanate) photocatalyst was prepared through the hydrothermal process for photodegradation of...     

Undecanoic and 10-Undecenoic Acid-Based Amidobetaines and Amidoamine Oxides

Three types of undecanoic and 10-undecenoic acid-based surfactants were synthesized in the present work: amphoteric amidobetaines, cationic amidobetaine chlorides and nonionic amidoamine oxides. Structural characterizations of synthesized compounds were based on nuclear magnetic resonance (NMR) (¹H and ¹³C) and mass spectrometry. Surface properties, such as critical micelle concentration (CMC), surface tension at cmc (γ _cmc), efficiency of surface adsorption (pC20), surface excess (Γ_max) and minimum area per molecule (A _min) at the air–water interface, were determined by surface tension methods. Fluorescence probing techniques were also employed for the measurement of CMC, as well as steady state anisotropy (r) at the micellar core. The CMC of the studied surfactants follow the order: amidobetaine > amidobetaine chloride > amidoamine oxide. The influence of the terminal double bond in the hydrophobic alkyl chain on CMC was also assessed, and a significant increase in CMC was found due to the introduction of the double bond in the cases of amidobetaine chlorides and amidoamine oxides. These two types of surfactants showed higher rigidity at the micellar core compared to their corresponding unsaturated counterparts. However, such influence of unsaturation on the hydrophobic moiety was not observed in the case of amidobetaines. In all three types of surfactants, the saturated surfactant exhibited a lower γ _cmc and A _min, but higher Γ_max, r and pC20 compared to its unsaturated counterpart.     

Application of non-hierarchical gadolinium ortho-ferrite nanostructure for LED-driven photocatalytic mineralization of doxycycline hydrochloride

Journal of Materials Science: Materials in Electronics - The present work demonstrates the glycol-assisted sol–gel process to yield gadolinium ortho-ferrite (GdFeO3) nanoparticles. The...