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Storage Properties (storage + property)
Kinds of Storage Properties Selected AbstractsSynthesis and Lithium Storage Properties of Co3O4 Nanosheet-Assembled Multishelled Hollow SpheresADVANCED FUNCTIONAL MATERIALS, Issue 10 2010Xi Wang Abstract Single-, double-, and triple-shelled hollow spheres assembled by Co3O4 nanosheets are successfully synthesized through a novel method. The possible formation mechanism of these novel structures was investigated using powder X-ray diffraction, scanning and transmission electron microscopies, Fourier transform IR, X-ray photoelectron spectroscopy, and thermogravimetric analysis. Both poly(vinylpyrrolidone) (PVP) soft templates and the formation of cobalt glycolate play key roles in the formation of these novel multishelled hollow structures. When tested as the anode material in lithium-ion batteries (LIBs), these multishelled microspheres exhibit excellent cycling performance, good rate capacity, and enhanced lithium storage capacity. This superior cyclic stability and capacity result from the synergetic effect of small diffusion lengths in the nanosheet building blocks and sufficient void space to buffer the volume expansion. This facile strategy may be extended to synthesize other transition metal oxide materials with hollow multishelled micro-/nanostrucutures, which may find application in sensors and catalysts due to their unique structural features. [source] Improved Hydrogen Storage Properties of Ti-Doped Sodium Alanate Using Titanium Nanoparticles as Doping Agents,ADVANCED MATERIALS, Issue 12 2003B. Bogdanovi By using nanosized doping agents, the properties of Ti-catalyzed NaAlH4 storage systems are considerably improved. Hydrogenation,dehydrogenation cyclic testing shows that with nanosized TiN dopants, storage capacities of 5 wt.-% H2 could be achieved. Doping with nanosized Ti brought hydrogenation times close to those required for practical applications, combined with high capacity (4.5 wt.-% H2, see Figure). [source] ChemInform Abstract: Calcium Amidoborane Ammoniate , Synthesis, Structure, and Hydrogen Storage Properties.CHEMINFORM, Issue 3 2010Yong Shen Chua Abstract ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a "Full Text" option. The original article is trackable via the "References" option. [source] ChemInform Abstract: Clewlike ZnV2O4 Hollow Spheres: Nonaqueous Sol,Gel Synthesis, Formation Mechanism, and Lithium Storage Properties.CHEMINFORM, Issue 48 2009Lifen Xiao Abstract ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a "Full Text" option. The original article is trackable via the "References" option. [source] Hydrogen Storage Properties of New Ternary Alloys: PrMg2Ni9 and PrMgNi4.CHEMINFORM, Issue 35 2005X. Xu Abstract For Abstract see ChemInform Abstract in Full Text. [source] Strategies for the Improvement of the Hydrogen Storage Properties of Metal Hydride MaterialsCHEMPHYSCHEM, Issue 15 2008Hui Wu Abstract Metal hydrides are an important family of materials that can potentially be used for safe, efficient and reversible on-board hydrogen storage. Light-weight metal hydrides in particular have attracted intense interest due to their high hydrogen density. However, most of these hydrides have rather slow absorption kinetics, relatively high thermal stability, and/or problems with the reversibility of hydrogen absorption/desorption cycling. This paper discusses a number of different approaches for the improvement of the hydrogen storage properties of these materials, with emphasis on recent research on tuning the ionic mobility in mixed hydrides. This concept opens a promising pathway to accelerate hydrogenation kinetics, reduce the activation energy for hydrogen release, and minimize deleterious possible by-products often associated with complex hydride systems. [source] ChemInform Abstract: Reversible Hydrogen Storage Property and Structural Analysis for Face-Centered Cubic Hydride Mg0.82Zr0.18H2 Prepared by Gigapascal Hydrogen Pressure Method.CHEMINFORM, Issue 12 2008Tomoaki Takasaki Abstract ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a "Full Text" option. The original article is trackable via the "References" option. [source] Using the Aggregation of Latex Polymers in the Fabrication of Reproducible Enzyme ElectrodesELECTROANALYSIS, Issue 17 2003Wibowo Rahmat Abstract An enzyme electrode for glucose is described as a model system to demonstrate a fabrication method using latex aggregation and entrapment of enzyme. Electrosterically-stabilized latex particles synthesized by emulsion polymerization in batch from acrylic acid, methyl methacrylate and butyl acrylate, and glucose oxidase were coagulated together at pH,5.5 with ethanol. A platinum disk electrode dipped in the solution becomes coated with latex/enzyme. The relative thickness of the film and relative amount of enzyme may be controlled by the time the electrode is in contact with the solution. The enzyme was then immobilized by covalent attachment of amine groups to carboxylic moieties in the polymer using 1-ethyl-3(3-dimethylaminopropyl)-carbodiimide hydrochloride and N -hydroxysuccinimide. Five minutes contact with the latex/enzyme solution and subsequent amide coupling, gave electrodes with a reproducibility of 5.7% RSD, a wide dynamic range (0,100,mM) and good storage properties. [source] Nanoscale Grain Refinement and H-Sorption Properties of MgH2 Processed by High-Pressure Torsion and Other Mechanical Routes,ADVANCED ENGINEERING MATERIALS, Issue 8 2010Daniel Rodrigo Leiva MgH2 is a promising material for solid-state hydrogen storage due to its high gravimetric and volumetric storage capacity and its relatively low cost. Severe plastic deformation (SPD) processing techniques are being explored as an alternative to high-energy ball-milling (HEBM) in order to obtain more air resistant materials and reduce processing times. In this work, Mg, MgH2, and MgH2,Fe mixtures were severely mechanically processed by different techniques such as high-pressure torsion (HPT), extensive cold forging, and cold rolling. A very significant grain refinement was achieved when using MgH2 instead of Mg as raw material. The mean crystallite sizes observed ranged from 10 to 30,nm, depending on the processing conditions. Enhanced H-sorption properties were observed for the MgH2 -based nanocomposites processed by HPT when compared with MgH2 mixtures. Additionally, cold forging and cold rolling also proved effective in nanostructuring MgH2. These results suggest a high potential for innovative application with the use of low cost mechanical processing routes to produce Mg-based nanomaterials with attractive hydrogen storage properties. [source] Interpretation of Spring Recession CurvesGROUND WATER, Issue 5 2002H. Amit Recession curves contain information on storage properties and different types of media such as porous, fractured, cracked lithologies and karst. Recession curve analysis provides a function that quantitatively describes the temporal discharge decay and expresses the drained volume between specific time limits (Hall 1968). This analysis also allows estimating the hydrological significance of the discharge function parameters and the hydrological properties of the aquifer. In this study, we analyze data from perennial springs in the Judean Mountains and from others in the Galilee Mountains, northern Israel. All the springs drain perched carbonate aquifers. Eight of the studied springs discharge from a karst dolomite sequence, whereas one flows out from a fractured, slumped block of chalk. We show that all the recession curves can be well fitted by a function that consists of two exponential terms with exponential coefficients ,1 and ,2. These coefficients are approximately constant for each spring, reflecting the hydraulic conductivity of different media through which the ground water flows to the spring. The highest coefficient represents the fast flow, probably through cracks, or quickflow, whereas the lower one reflects the slow flow through the porous medium, or baseflow. The comparison of recession curves from different springs and different years leads to the conclusion that the main factors that affect the recession curve exponential coefficients are the aquifer lithology and the geometry of the water conduits therein. In normal years of rainy winter and dry summer, ,1 is constant in time. However, when the dry period is longer than usual because of a dry winter, ,1 slightly decreases with time. [source] Assessing the impact of mixing assumptions on the estimation of streamwater mean residence timeHYDROLOGICAL PROCESSES, Issue 12 2010Fabrizio Fenicia Abstract Catchment streamwater mean residence time (Tmr) is an important descriptor of hydrological systems, reflecting their storage and flow pathway properties. Tmr is typically inferred from the composition of stable water isotopes (oxygen-18 and deuterium) in observed rainfall and discharge. Currently, lumped parameter models based on convolution and sinewave functions are usually used for tracer simulation. These traditional models are based on simplistic assumptions that are often known to be unrealistic, in particular, steady flow conditions, linearity, complete mixing and others. However, the effect of these assumptions on Tmr estimation is seldom evaluated. In this article, we build a conceptual model that overcomes several assumptions made in traditional mixing models. Using data from the experimental Maimai catchment (New Zealand), we compare a complete-mixing (CM) model, where rainfall water is assumed to mix completely and instantaneously with the total catchment storage, with a partial-mixing (PM) model, where the tracer input is divided between an ,active' and a ,dead' storage compartment. We show that the inferred distribution of Tmr is strongly dependent on the treatment of mixing processes and flow pathways. The CM model returns estimates of Tmr that are well identifiable and are in general agreement with previous studies of the Maimai catchment. On the other hand, the PM model,motivated by a priori catchment insights,provides Tmr estimates that appear exceedingly large and highly uncertain. This suggests that water isotope composition measurements in rainfall and discharge alone may be insufficient for inferring Tmr. Given our model hypothesis, we also analysed the effect of different controls on Tmr. It was found that Tmr is controlled primarily by the storage properties of the catchment, rather than by the speed of streamflow response. This provides guidance on the type of information necessary to improve Tmr estimation. Copyright © 2010 John Wiley & Sons, Ltd. [source] Investigating mechanisms of stormflow generation by natural tracers and hydrometric data: a small catchment study in the Black Forest, GermanyHYDROLOGICAL PROCESSES, Issue 2 2001E. Hangen Abstract The importance and interaction of various hydrological pathways and identification of runoff source areas involved in solute transport are still under considerable debate in catchment hydrology. To reveal stormflow generating areas and flow paths, hydrometric behaviour of throughfall, soil water from various depths, runoff, and respective concentrations of the environmental tracers 18O, Si, K, SO4 and dissolved organic carbon were monitored for a 14-week period in a steep headwater catchment in the Black Forest Mountains, Germany. Two stormflow hydrographs were selected and, based on 18O and Si, chemically separated into three flow components. Their sources were defined using mixing diagrams. Additional information about stormflow generating mechanisms was derived from recession analyses of the basin's complete 5-year hydrograph record. By providing insight into storage properties and residence times of outflowing reservoirs of the basin, recession analysis proved to be a valuable tool in runoff model conceptualization. Its results agreed well with hydrometric and hydrochemical data. Supported by evaluation of 30 hillslope soil profiles a coherent concept of stormflow generation could be derived: whereas in many steeply sloped basins in the temperate region soil water from hillslopes appears to have an immediate effect on the shape of the stormflow hydrograph, its role at this basin is basically restricted to the recharge of the groundwater reservoir in the near-channel area. Storm hydrograph peaks appear to be derived from a small direct runoff component supplemented by a fast delivery of baseflow from the groundwater reservoir in the valley bottom. Copyright © 2001 John Wiley & Sons, Ltd. [source] High-Performance, Nondiffusive Crosslinked Polymers for Holographic Data Storage,ADVANCED MATERIALS, Issue 20 2008Anzar Khan High-performance crosslinked polymeric materials for 3D data storage are described. Their performance is based on photoisomerization of Dewar benzene derivatives, and they exhibit remarkable information storage properties including excellent photosensitivity, high data-storage capacity, good dimensional stability, and significant shelf- and archival-lifetimes. [source] Hydrogen storage properties of B- and N-doped microporous carbonAICHE JOURNAL, Issue 7 2009Lifeng Wang Abstract A B- and N-doped microporous carbon has been synthesized via a substitution reaction. The obtained carbon exhibited much higher surface area than the previously reported B- and N-doped carbon. The hydrogen storage measurements indicated that the B- and N-doped microporous carbon had a 53% higher storage capacity than the carbon materials with similar surface areas. Furthermore, hydrogen storage via spillover was studied on Ru-supported B- and N-doped microporous carbon and a storage capacity of 1.2 wt % at 298 K and 10 MPa was obtained, showing an enhancement factor of 2.2. Ab initio molecular orbital calculations were also performed for the binding energies between the spiltover hydrogen atom and various sites on the doped carbon. The theoretical calculations can explain the experimental results well, which also shed light on the most favorable and possible sites with which the spiltover hydrogen atoms bind. © 2009 American Institute of Chemical Engineers AIChE J, 2009 [source] Olive oil production on bronze age Crete: nutritional properties, processing methods and storage life of Minoan olive oilOXFORD JOURNAL OF ARCHAEOLOGY, Issue 1 2002F.R. Riley Archaeological studies on olive oil produced in Crete in the Bronze Age focus primarily on aspects such as the period when olive cultivation became widespread, the number of olive trees cultivated, or the quantity of oil stored in the Minoan palaces. Olive oil is however an organic substance, a perishable product, the nutritional and storage properties of which are determined by environmental, agronomic, processing and storage conditions. In this paper archaeological, environmental and biochemical evidence is combined to present a comprehensive picture of the potential quality, nutritional and storage properties of Minoan olive oil. The comparative evidence presented suggests that Minoan olive oil was equal in quality to the cold-pressed virgin olive oils produced today, and as such, the oil was nutritionally important in the Bronze Age and a valuable trade commodity. [source] Dynamics of water transport and storage in conifers studied with deuterium and heat tracing techniquesPLANT CELL & ENVIRONMENT, Issue 1 2006F. C. MEINZER ABSTRACT The volume and complexity of their vascular systems make the dynamics of long-distance water transport in large trees difficult to study. We used heat and deuterated water (D2O) as tracers to characterize whole-tree water transport and storage properties in individual trees belonging to the coniferous species Pseudotsuga menziesii (Mirb.) Franco and Tsuga heterophylla (Raf.) Sarg. The trees used in this study spanned a broad range of height (13.5,58 m) and diameter (0.14,1.43 m). Sap flow was monitored continuously with heat dissipation probes near the base of the trunk prior to, during and following injection of D2O. The transit time for D2O transport from the base of the trunk to the upper crown and the tracer residence time were determined by measuring hydrogen isotope ratios in water extracted from leaves sampled at regular intervals. Transit times for arrival of D2O in the upper crown ranged from 2.5 to 21 d and residence times ranged from 36 to 79 d. Estimates of maximum sap velocity derived from tracer transit times and path length ranged from 2.4 to 5.4 m d,1. Tracer residence time and half-life increased as tree diameter increased, independent of species. Species-independent scaling of tracer velocity with sapwood-specific conductivity was also observed. When data from this study were combined with similar data from an earlier study of four tropical angiosperm trees, species-independent scaling of tracer velocity and residence time with sapwood hydraulic capacitance was observed. Sapwood capacitance is an intrinsic tissue-level property that appears to govern whole-tree water transport in a similar manner among both tracheid- and vessel-bearing species. [source] Strategies for the Improvement of the Hydrogen Storage Properties of Metal Hydride MaterialsCHEMPHYSCHEM, Issue 15 2008Hui Wu Abstract Metal hydrides are an important family of materials that can potentially be used for safe, efficient and reversible on-board hydrogen storage. Light-weight metal hydrides in particular have attracted intense interest due to their high hydrogen density. However, most of these hydrides have rather slow absorption kinetics, relatively high thermal stability, and/or problems with the reversibility of hydrogen absorption/desorption cycling. This paper discusses a number of different approaches for the improvement of the hydrogen storage properties of these materials, with emphasis on recent research on tuning the ionic mobility in mixed hydrides. This concept opens a promising pathway to accelerate hydrogenation kinetics, reduce the activation energy for hydrogen release, and minimize deleterious possible by-products often associated with complex hydride systems. [source] Studies on a New Material for Hydrogen Storage and Supply by Modified Fe and Fe2O3 PowderCHINESE JOURNAL OF CHEMISTRY, Issue 7 2007Hui Wang Abstract Modified iron oxide, a new material for hydrogen storage and supply to polymer electrolyte fuel cell (PEFC), was prepared by impregnating Fe or Fe2O3 powder with an aqueous solution containing metal cation additives (Al, Cr, Ni, Co, Zr and Mo). Hydrogen storage properties of the samples were investigated. The results show that both Fe and Fe2O3 powder with additive Mo presented excellent catalytic activity and cyclic stability, and their hydrogen producing temperature could be surprisingly decreased. The temperature of forming hydrogen for the Fe2O3 -Mo at the rate of 250 µmol·min,1·Fe-g,1 could be dramatically decreased from 527 °C before addition of Mo to 283 °C after addition of Mo in the fourth cycle. The cause for it was probably related to preventing the sinter of the sample particles. In addition, hydrogen storage capacity of the Fe2O3 -Mo can reach w=4.5% (72 kg H2/m3), close to International Energy Agency (IEA) criterion. These show the value of practical application of the Fe2O3 -Mo as the promising hydrogen storage material. [source] | ||||||||||||||||