Raising Energy Efficiency of High-Head Drinking Water Pumping Schemes in Hilly India – Massive Potential, Complex Challenges

Investigations of energy efficiency of 25 pumps showed wire-to-water efficiencies ranging from 30% to 60%, with an average of 47%. Raising the efficiency of just 7 pumps to the realistic target of 60% would require an initial investment of 126 k€ and represent a net present value (profit) of 446 k€ over a 10-year pump lifetime, saving 8.6 kt of CO2 emissions. The primary measures for raising efficiency are in order of priority: 1) improving pre-filtration of raw water to prevent rapid mechanical wear due to suspended particles during monsoon, 2) providing training, improved working conditions, and better tools and spare parts among pump operators and 3) replacing aging, oversized pumps with properly sized pumps operating close to peak efficiency. As of January 2014 the results have been confirmed by a Bureau of Energy Efficiency-certified energy auditor and the extent and funding of efficiency measures implementation is in planning

Improved Durability of Wood Treated with Nano Metal Fluorides against Brown-Rot and White-Rot Fungi

Low-water soluble metal fluorides such as magnesium fluoride (MgF2) and calcium fluoride (CaF2) were evaluated for decay protection of wood. Initially, the biocidal efficacy of nano metal fluorides (NMFs) against wood destroying fungi was assessed with an in-vitro agar test. The results from the test showed that agar medium containing MgF2 and CaF2 was more efficient in preventing fungal decay than stand-alone MgF2 or CaF2. These metal fluorides, in their nanoscopic form synthesized using fluorolytic sol-gel synthesis, were introduced into the sapwood of Scots pine and beech wood and then subjected to accelerated ageing by leaching (EN 84). MAS 19F NMR and X-ray micro CT images showed that metal fluorides were present in treated wood, unleached and leached. Decay resistance of Scots pine and beech wood treated with NMFs was tested against wood destroying fungi Rhodonia placenta and Trametes versicolor in accordance with EN 113. Results revealed that mass losses were reduced to below 3% in wood treated with the combination of MgF2 and CaF2. It is concluded that NMFs provide full protection to wood even after it has been leached and can be used as wood preservatives in outdoor environments.Peer Reviewe

Synthesis of ternary transition metal fluorides Li 3MF 6via a sol-gel route as candidates for cathode materials in lithium-ion batteries

A sol-gel route for ternary lithium fluorides of transition metals (M) is presented allowing the synthesis of Li 3MF 6-type and Li 2MF 5-type compounds. It is based on a fluorolytic process using transition metal acetylacetonates as precursors. The domain size of the obtained powders can be controlled by modifying the conditions of synthesis. 6Li and 7Li magic angle spinning (MAS) nuclear magnetic resonance (NMR) spectroscopy is used to study local environments of the Li ions in orthorhombic and monoclinic Li 3VF 6 as well as Li 2MnF 5. The number of magnetically inequivalent Li sites found by MAS NMR is in agreement with the respective crystal structure of the compounds studied. Quantum chemical calculations show that all materials have high de-lithiation energies making them suitable candidates to be used as high-voltage battery cathode materials. © 2012 The Royal Society of Chemistry

Preparation of NHC Stabilized Al(III)fluorides: Fluorination of [(SIMes)AlMe3] with SF4 or Me3SnF

Various reaction routes have been developed to synthesize the N‐heterocyclic carbene (NHC) stabilized Al(III) fluorides [(SIMes)Al(F)3] (2) and [(SIMes)Al(F)Me2] (3) through fluorination of [(SIMes)AlMe3] (1) (SIMes: 1,3‐bis(2,4,6‐trimethylphenyl)‐imidazolidin‐2‐ylidene) with fluorinating agents such as SF4, SF6 and Me3SnF. The reactivity of 2 was investigated towards a F/Cl exchange reaction by treating it with Me3SiCl.Peer Reviewe

Termite resistance of pine wood treated with nano metal fluorides

Fluorides are well-known as wood preservatives. One of the limitations of fluoride-based wood preservatives is their high leachability. Alternative to current fluoride salts such as NaF used in wood protection are low water-soluble fluorides. However, impregnation of low water-soluble fluorides into wood poses a challenge. To address this challenge, low water-soluble fluorides like calcium fluoride (CaF2) and magnesium fluoride (MgF2) were synthesized as nanoparticles via the fluorolytic sol−gel synthesis and then impregnated into wood specimens. In this study, the toxicity of nano metal fluorides was assessed by termite mortality, mass loss and visual analysis of treated specimens after eight weeks of exposure to termites, Coptotermes formosanus. Nano metal fluorides with sol concentrations of 0.5 M and higher were found to be effective against termites resulting in 100% termite mortality and significantly inhibited termite feeding. Among the formulations tested, the least damage was found for specimens treated with combinations of CaF2 and MgF2 with an average mass loss less than 1% and visual rating of “1”. These results demonstrate the efficacy of low water-soluble nano metal fluorides to protect wood from termite attack.Peer Reviewe

A HF Loaded Lewis-Acidic Aluminium Chlorofluoride for Hydrofluorination Reactions

The very strong Lewis acid aluminium chlorofluoride (ACF) was loaded with anhydrous HF. The interaction between the surface of the catalyst and HF was investigated using a variety of characterization methods, which revealed the formation of polyfluorides. Moreover, the reactivity of the HF-loaded ACF towards the hydrofluorination of alkynes was studied.Peer Reviewe