Synthesis and characterisation of a new high pressure polymorph of Cu2WS4

In this communication we report the synthesis and structural characterisation of a new body centred polymorph of Cu2WS4 prepared using hydrothermal methods. I-Cu2WS4 crystallises in space group I (4) over bar 2m with cell parameters a = b = 5.44427(8), c = 10.0687(2) Angstrom and has a new structure type containing layers of edge-sharing CuS4 and WS4 tetrahedra

Synthesis and characterisation of a new high pressure polymorph of Cu2WS4

In this communication we report the synthesis and structural characterisation of a new body centred polymorph of Cu2WS4 prepared using hydrothermal methods. I-Cu2WS4 crystallises in space group I (4) over bar 2m with cell parameters a = b = 5.44427(8), c = 10.0687(2) Angstrom and has a new structure type containing layers of edge-sharing CuS4 and WS4 tetrahedra

The synthesis and characterisation of Cu₂MX₄ (M = W or Mo; X = S, Se or S/Se) materials prepared by a solvothermal method

This paper describes the synthesis of a family of layered materials with general formula Cu2MX4 (M = W or Mo; X = S, Se or S/Se) by a solvothermal route. The effect of synthesis temperature has been investigated and found to determine the structural form of the material produced. The structures of all materials have been solved and refined using powder X-ray diffraction. Variable temperature diffraction experiments have been performed on Cu2WS4 and Cu2WSe4. Conductivity measurements show Cu2WSe4 is semiconducting

Diurnal lipid and mucus production in the staghorn coral Acropora acuminata

Net 14C-accumulation into lipids of Acropora acuminata was rapid and increased with light intensity. Dark 14C-incorporation was less than 1% noon maximum. Structural lipids were the first radioactively labelled lipid types showing linear 14C-uptake kinetics. Storage lipids showed non-linear, power-curve kinetics for 14C-uptake. The rate of 14C-incorporation into triglycerides and wax esters was maximal during early afternoon and at midday, respectively. Electron microscopic evidence is given for zooxanthellae being primary sites for synthesis of lipids which are exuded from chloroplasts and transferred to animal tissues. Free lipid droplets and crystalline inclusions (wax ester) were common in animal tissues, the inclusions being often associated with mucus-producing cells. The diurnal rate of mucus production was constant. However, 14C-mucus-lipid production showed a light-dependent diurnal pattern and accounted for 60 to 90% total 14C of mucus during periods of photosynthetically-saturating light. Here, 14C was primarily associated with wax esters which were always present in the mucus-lipid. 14C-triglycerides occur in mucus released only during the day. Lipid and mucus synthesis is discussed in relation to the carbon budget of A. acuminata, in which mucus represented a loss of 40% net C fixation

A Linear Programming Approach for Battery Degradation Analysis and Optimization in Offgrid Power Systems with Solar Energy Integration

Storage technologies and storage integration are currently key topics of research in energy systems, due to the resulting possibilities for reducing the costs of renewables integration. Off-grid power systems in particular have received wide attention around the world, as they allow electricity access in remote rural areas at lower costs than grid extension. They are usually integrated with storage units, especially batteries. A key issue in cost effectiveness of such systems is battery degradation as the battery is charged and discharged. We present linear programming models for the optimal management of off-grid systems. The main contribution of this study is developing a methodology to include battery degradation processes inside the optimization models, through the definition of battery degradation costs. As there are very limited data that can be used to relate the battery usage with degradation issues, we propose sensitivity analyses to investigate how degradation costs and different operational patterns relate each others. The objective is to show the combinations of battery costs and performance that makes the system more economic

Spawning and nursery habitat partitioning and movement patterns of Pagrus auratus (Sparidae) on the lower west coast of Australia

The ages and lengths of Pagrus auratus caught by line fishing in three marine embayments (Owen Anchorage, Cockburn Sound and Warnrbo Sound) and inshore (80. m depth) on the lower west coast of Australia (31°45'-32°45' S) were used to infer the movement patterns and habitats occupied by this species at different stages in its life cycle on this coast. These data were supplemented by results obtained by tagging individuals in spawning aggregations in the embayments. 0+ P. auratus <200. mm FL were caught exclusively in the three adjacent embayments. The ages and lengths of immature P. auratus, ranging from 1+ (ca. 200. mm FL) to 5+ years (ca. 400. mm FL), increased progressively with distance from these embayments. During the spawning period (from September to January), the relative abundances of P. auratus with either developing, developed or recently spent gonads were far greater in the three embayments (91%) than in either inshore (12%) or offshore waters (30%). Some tagged P. auratus were recaptured among spawning aggregations in the same embayment during subsequent spawning seasons, while others were recaptured in these embayments outside the spawning period. However, some other tagged individuals were recaptured up to 92. km north, 33. km west and 134. km south outside the spawning period and up to five years after tagging. The results of this study emphasise that the above three adjacent marine embayments constitute important spawning and nursery areas for P. auratus and are thus potentially critical for sustaining the stocks of this recreationally and commercially important species on the lower west coast of Australia

Synthesis and NMR studies of O-17 enriched AM(2)O(8) phases

This paper describes synthetic routes to produce highly O-17 enriched samples of the negative thermal expansion materials ZrW2O8 and ZrMo2O8. In the case of ZrW2O8 enriched samples can be produced either via enriched Zr-17 O-2 and (WO3)-O-17, which have themselves been characterised by both X-ray diffraction and solid state O-17 NMR, or via the hydrated material ZrW2O8-xH(2) O-17. In the case of ZrMo2O8 energy dispersive in-situ diffraction experiments have shown that cubic ZrMo2O8 can be directly hydrated to form an enriched sample of ZrMo2O7(OH)(2)-2H2O which can subsequently be transformed back to enriched cubic ZrMo2O8. O-17 NMR data of enriched ZrW2O8 materials are reported. (c) 2005 Elsevier SAS. All rights reserved