Crystal structure of melaminium cyanoacetate monohydrate

The asymmetric unit of the title compound, 2,4,6-tri­amino-1,3,5-triazin-1-ium cyano­acetate monohydrate, C3H7N6+·NCCH2COO−·H2O, consists of a melaminium cation, a cyano­acetate anion and a water mol­ecule, which are connected to each other via N—H⋯O and O—H⋯O hydrogen bonds, generating an eight-membered ring. In the crystal, the melaminium cations are connected by two pairs of N—H⋯N hydrogen bonds, forming tapes along [110]. These tapes develop a three-dimensional network through N—H⋯O, O—H⋯O, N—H⋯N and C—H⋯O hydrogen bonds between the cations, anions and water mol­ecules

Synthesis and reactions of triply bonded sulphur-nitrogen compounds

Bibliography: p. 220-236

Nanotechnology for water treatment and purification

This book describes the latest progress in the application of nanotechnology for water treatment and purification. Leaders in the field present both the fundamental science and a comprehensive overview of the diverse range of tools and technologies that have been developed in this critical area. Expert chapters present the unique physicochemical and surface properties of nanoparticles and the advantages that these provide for engineering applications that ensure a supply of safe drinking water for our growing population. Application areas include generating fresh water from seawater, preventing contamination of the environment, and creating effective and efficient methods for remediation of polluted waters. The chapter authors are leading world-wide experts in the field with either academic or industrial experience, ensuring that this comprehensive volume presents the state-of-the-art in the integration of nanotechnology with water treatment and purification. Covers both wastewater and drinking water treatment Provides concise yet thorough coverage of the fundamentals of nanomaterials and treatment processes as well as insights into future R&D trends Presents the latest progress in research and prototype testing lines Written for a broad audience of engineers, researchers, municipal water managers, and policymaker

Nanotechnology for Water Treatment and Purification

XVI, 373 p. 137 illus., 78 illus. in color.onlin

Nanomaterials via Single-Source Precursors Synthesis, Processing and Applications

Nanomaterials via Single-Source Precursors: Synthesis, Processing and Applications presents recent results and overviews of synthesis, processing, characterization and applications of advanced materials for energy, electronics, biomedicine, sensors and aerospace. A variety of processing methods (vapor, liquid and solid-state) are covered, along with materials, including metals, oxides, semiconductor, sulfides, selenides, nitrides, and carbon-based materials. Production of quantum dots, nanoparticles, thin films and composites are described by a collection of international experts. Given the ability to customize the phase, morphology, and properties of target materials, this “rational approach” to synthesis and processing is a disruptive technology for electronic, energy, structural and biomedical (nano)materials and devices. The use of single-source chemical precursors for materials processing technology allows for intimate elemental mixing and hence production of complex materials at temperatures well below traditional physical methods and those involving direct combination of elements. The use of lower temperatures enables thin-film deposition on lightweight polymer substrates and reduces damage to complex devices structures such as used in power, electronics and sensors

Synthesis and Properties of Anion Exchangers Derived from Chloromethyl Styrene Codivinylbenzene and Their Use in Water Treatment

Amination of vinylbenzyl chloride-divinylbenzene (VBC-DVB) copolymers is an effective method for preparation of ion-exchange resins. Conventionally, the starting polymer is produced by chloromethylation of a styrene-divinylbenzene copolymer that utilizes chloromethyl methyl ether, a known carcinogen. An alterative approach is to copolymerize vinylbenzyl chloride with divinylbenzene to generate the necessary VBC-DVB. This method provides precise control over the density of the ion-exchange groups. The regiochemistry of the vinylbenzyl chloride methods was realized using solvent-ion exchange groups. In this investigation, an improved solvent system was found for the preparation of anion exchange resins by the vinylbenzyl chloride route. The effectiveness of amination of the intermediate VBC-DVB polymers with a variety of trimethylamine reagents was investigated, and ethanolic trimethylamine produced the highest degree of amination. These resulting ion-exchange polymers were characterized by a variety of techniques such as analytical titrations, nitrogen analysis, Fourier transform infrared spectroscopy and thermal gravimetric analysis. Testing of these copolymers for breakthrough was performed. The results indicate that these anion exchangers have a meaningful increase in thermal stability over commercial anionic exchange beads

Doping Efficiency in Cobalt-Doped ZnO Nanostructured Materials

Nanostructured ZnO thin films doped with cobalt from 5% to 20% were grown on glass substrates by a low-temperature chemical bath deposition (CBD) technique. We compared the doping efficiency of incorporating cobalt in ZnO nanostructured samples doped with cobalt via cobalt nitrate and cobalt chloride. The concentration of cobalt incorporated into the ZnO matrix was precisely determined using inductively coupled plasma mass spectroscopy (ICP-MS). Scanning electron microscopy (SEM) images showed that only at a 0.1 M ratio of the precursor solutions in CBD using cobalt nitrate as a dopant, the morphology of ZnO yielded hexagonally shaped nanorods. At a 1 M ratio of the precursor solutions, SEM images showed that the morphology of ZnO was nanoplatelets at all doping levels, irrespective of the doping method used. The synthesized nanostructures retained the wurtzite hexagonal structure only at 0.1 M precursor solution using cobalt nitrate doping, which was confirmed by X-ray diffraction (XRD) studies. In cobalt-doped samples using cobalt chloride as a dopant, XRD analysis confirmed the formation of a Simonkolleite structure. At 300°C, the Simonkolleite structure was converted to a wurtzite structure without changing the morphology. Electrical conductivity measurements at 300 K showed that ZnO nanorods doped with cobalt using cobalt nitrate yielded the lowest resistivity. The molarity of the precursor solution and dopant was found to have a substantial impact on the morphology and doping efficiency of the ZnO nanostructures