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991.
The performance of mixed bi-material electrodes composed of the battery material, LiMn2O4, and the electrochemical capacitor material, activated carbon, for hybrid electrochemical energy storage devices is investigated by galvanostatic charge/discharge and pulsed discharge experiments. Both, a high and a low conductivity lithium-containing electrolyte are used. The specific charge of the bi-material electrode is the linear combination of the specific charges of LiMn2O4 and activated carbon according to the electrode composition at low discharge rates. Thus, the specific charge of the bi-material electrode falls between the specific charge of the activated carbon electrode and the LiMn2O4 battery electrode. The bi-material electrodes have better rate capability than the LiMn2O4 battery electrode. For high current pulsed applications the bi-material electrodes typically outperform both the battery and the capacitor electrode. 相似文献
992.
Filak LK Mühlgassner G Bacher F Roller A Galanski M Jakupec MA Keppler BK Arion VB 《Organometallics》2011,30(2):273-283
The synthesis of new modified indolo[3,2-c]quinoline ligands L(1)-L(8) with metal-binding sites is reported. By coordination to ruthenium- and osmium-arene moieties 16 complexes of the type [(η(6)-p-cymene)M(L)Cl]Cl (1a,b-8a,b), where M is Ru(II) or Os(II) and L is L(1)-L(8), have been prepared. All compounds were comprehensively characterized by elemental analysis, electrospray ionization mass spectrometry, IR, UV-vis, and NMR spectroscopy, thermogravimetric analysis, and single-crystal X-ray diffraction (2a, 4a, 4b, 5a, 7a, and 7b). The complexes were tested for antiproliferative activity in vitro in three human cancer cell lines, namely, CH1 (ovarian carcinoma), SW480 (colon adenocarcinoma), and A549 (non-small-cell lung cancer), yielding IC(50) values in the submicromolar or low micromolar range. 相似文献
993.
Robyn Fowler Driton Vllasaliu Francisco Fernández Trillo Martin Garnett Cameron Alexander Helen Horsley Bryan Smith Ian Whitcombe Mike Eaton Snow Stolnik 《Small (Weinheim an der Bergstrasse, Germany)》2013,9(19):3282-3294
The understanding and control of nanoparticle transport into and through cellular compartments is central to biomedical applications of nanotechnology. Here, it is shown that the transport pathway of 50 nm polystyrene nanoparticles decorated with vitamin B12 in epithelial cells is different compared to both soluble B12 ligand and unmodified nanoparticles, and this is not attributable to B12 recognition alone. Importantly, the study indicates that vitamin B12‐conjugated nanoparticles circumnavigate the lysosomal compartment, the destination of soluble vitamin B12 ligand. Whereas cellular trafficking of soluble B12 is confirmed to occur via the clathrin‐mediated pathway, transport of B12‐conjugated nanoparticles appears to predominantly take place by a route that is perturbed by caveolae‐specific inhibitors. This data suggests that, following its conjugation to nanoparticles, in addition to dramatically increasing the cellular uptake of nanoparticles, the normal cell trafficking of B12 is switched to an alternative pathway, omitting the lysosomal stage: a result with important implications for oral delivery of nanoparticulate diagnostics and therapeutics. 相似文献
994.
Shen Zhao Dong Su Justin Che Bingyin Jiang Alexander Orlov 《Materials Letters》2011,65(23-24):3354-3357
In this study, the new class of SBA-15 mesoporous materials with large pore diameter and short pore channels has been utilized as template for TiO2 based photocatalysts. The samples were characterized by TEM, SAXS, and BET and tested for photocatalytic activity in liquid phase oxidation of phenol. This is the first ever application of this type of SBA-15 supported catalyst in photocatalytic area. This work also included the novel use of sub-1 nm Au nanoparticles for catalysts modification which doubles the phenol oxidation rate. 相似文献
995.
996.
Ryan C. Sullivan Meagan J. K. Moore Markus D. Petters Sonia M. Kreidenweis Odeta Qafoku Alexander Laskin 《Aerosol science and technology》2013,47(10):830-846
Calcite (CaCO 3 ) mineral particles are commonly generated by atomization techniques to study their heterogeneous chemistry, hygroscopicity, and cloud nucleation properties. Here we investigate the significant artifact introduced in generating calcium mineral particles through the atomization of a saturated suspension of the powder in water, by measuring particle hygroscopicity via CCN activation curves. Particles produced from atomization displayed hygroscopicities as large as κapp > 0.1, 100 times more hygroscopic than that obtained for dry-generated calcite, κapp = 0.0011. The hygroscopicity of the wet-generated particles increased as a function of time the calcite powder spent in water, and with decreasing particle size. Wet-generated calcium oxalate was more hygroscopic through wet- (κapp = 0.34) versus dry-generation (κapp = 0.048). Atomized calcium sulfate particles, however, were only slightly more hygroscopic (κapp = 0.0045) than those generated dry (κapp = 0.0016). Single-particle analysis by ATOFMS and SEM/EDX, and bulk analysis of the calcite powders by ICP-MS and IC revealed no significant soluble contaminants. The atomized particles were likely composed of components that dissolved from the powder and then re-precipitated, and appeared to contain little of the original mineral powder. The increased hygroscopicity of atomized calcite may have been caused by aqueous carbonate chemistry producing Ca(OH) 2 , Ca(HCO 3 ) 2 , and metastable hydrates with increased solubility. Surface water adsorption may have also played a role, in addition to uncharacterized soluble components produced by wet-generation, and the precipitation of amorphous phases including glassy states. This study suggests that using wet-generation methods to suspend mineral dust samples will not produce particles with the correct physicochemical properties in laboratory studies, a finding which has important implications for past and future laboratory studies focusing on understanding relationships between the hygroscopicity and chemistry of mineral dust particles. 相似文献
997.
Amino acids present in beer and wort samples were isolated using Dowex 50W-X8 ion exchange resin. These acids were converted to N-trifluoroacetyl methyl esters and were separated on a 10 ft. x 1/4 in. copper column packed with 3/4% Carbowax 1540 and 1/4% NPGS on Chromosorb W. Complete separation and quantitative estimation was obtained for eleven amino acids: valine, alanine, isoleucine, leucine, glycine, proline, aspartic acid, threonine, methionine, glutamic acid, and phenylalanine. Standards of the acids showed a relative standard deviation of 4% and less for nine acids while threonine and methionine gave deviations of 9% and 15% respectively. The other naturally-occurring amino acids did not interfere with the separation of the above eleven. Amino acid assimilation data is presented along with other beer and wort analyses. 相似文献
998.
We investigate the effect of the geometry of granular heaps on the pressure distribution. For given pressure distributions under cones we compute the pressure distribution under wedges using linear superposition. For cones with a pressure minimum, the pressure minimum for the corresponding wedge vanishes. Comparisons with experimental data gives good qualitative aggreement, but the total pressure is overestimated. 相似文献
999.
Alexander Brodsky Yehoshua Sagiv 《Annals of Mathematics and Artificial Intelligence》1999,26(1-4):29-57
Datalog (i.e., function-free logic) programs with monotonicity constraints on extensional predicates are considered. A monotonicity
constraint states that one argument of a predicate or a constant is always less than another argument or a constant, according
to some strict partial order. Relations of an extensional database are required to satisfy the monotonicity constraints imposed
on their predicates. More specifically, a strict partial order is defined on the domain (i.e., set of constants) of the database,
and every tuple of each relation satisfies the monotonicity constraints imposed on its predicate. This paper focuses on the
problem of entailment of monotonicity constraints in the intensional database from monotonicity constraints in the extensional
database. The entailment problem is proven to be decidable, based on a suggested algorithm for computing sound and complete
disjunctions of monotonicity and equality constraints that hold in the intentional database. It is also shown that the entailment
of monotonicity constraints in programs is a complete problem for exponential time. For linear programs, this problem is complete
for polynomial space.
This revised version was published online in June 2006 with corrections to the Cover Date. 相似文献
1000.
Theoretical expressions were developed for the design of a tubular reactor for the calcination of limestone, pneumatically conveyed by flue gas. The total residence time and the length of the reactor are affected in particular by the particle size, the excess thermal capacity of the gas and the heat transfer coefficient. High throughput can be achieved in relatively small reactors. An experimental investigation verified a theoretical prediction, that a considerable part of the decomposition takes place in the first few centimeters of the reactor length. The rate of heat transfer in this section was high, with Nusselt numbers of 9.9 to 31.7. 相似文献