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排序方式: 共有73条查询结果,搜索用时 46 毫秒
1.
Kenna L. Salvatore Diana M. Lutz Dr. Haoyue Guo Dr. Shiyu Yue Joceline Gan Dr. Xiao Tong Dr. Ping Liu Dr. Esther S. Takeuchi Dr. Kenneth J. Takeuchi Dr. Amy C. Marschilok Dr. Stanislaus S. Wong 《Chemistry (Weinheim an der Bergstrasse, Germany)》2020,26(42):9389-9402
Solution-based, anionic doping represents a convenient strategy with which to improve upon the conductivity of candidate anode materials such as Li4Ti5O12 (LTO). As such, novel synthetic hydrothermally-inspired protocols have primarily been devised herein, aimed at the large-scale production of unique halogen-doped, micron-scale, three-dimensional, hierarchical LTO flower-like motifs. Although fluorine (F) doping has been explored, the use of chlorine (Cl) dopants is the primary focus here. Several experimental variables, such as dopant amount, lithium hydroxide concentration, and titanium butoxide purity, were probed and perfected. Furthermore, the Cl doping process did not damage the intrinsic LTO morphology. The analysis, based on interpreting a compilation of SEM, XRD, XPS, and TEM-EDS results, was used to determine an optimized dopant concentration of Cl. Electrochemical tests demonstrated an increased capacity via cycling of 12 % for a Cl-doped sample as compared with pristine LTO. Moreover, the Cl-doped LTO sample described in this study exhibited the highest discharge capacity yet reported at an observed rate of 2C for this material at 143mAh g−1. Overall, these data suggest that the Cl dopant likely enhances not only the ion transport capabilities, but also the overall electrical conductivity of our as-prepared structures. To help explain these favorable findings, theoretical DFT calculations were used to postulate that the electronic conductivity and Li diffusion were likely improved by the presence of increased Ti3+ ion concentration coupled with widening of the Li migration channel. 相似文献
2.
Analytical and Bioanalytical Chemistry - 相似文献
3.
Stanislaus Jolles 《Mathematische Zeitschrift》1927,26(1):177-185
Ohne Zusammenfassung 相似文献
4.
Stanislaus Jolles 《Mathematische Zeitschrift》1920,8(1-2):91-95
Ohne Zusammenfassung 相似文献
5.
Zorbas V Kanungo M Bains SA Mao Y Hemraj-Benny T Misewich JA Wong SS 《Chemical communications (Cambridge, England)》2005,(36):4598-4600
A spatially confined photocatalytic oxidation of a thin film of synthetic textile azo dye (Procion Red MX-5B) using TiO2-functionalized AFM probes is described. 相似文献
6.
An ozonolysis protocol has recently been developed that cannot only purify nanotubes but also achieve rational spatial and molecular control over chemical derivatization in single-walled carbon nanotubes (SWCNTs). Ozonolysis likely opens end caps and introduces holes into the sidewalls of tubes, which may occur through an oxidation of carbon atoms located on the nanotube surface, resulting in the formation of oxygen-containing functional groups. Overall, it was demonstrated by analysis of nitrogen adsorption and TGA/DTG that the total surface area, micropore volume, and mesopore volume of SWCNTs depend on several, intertwined factors including the degree of purity, surface functionality, density of surface groups, as well as the state of aggregation of the carbon tubes. Hydrogen bonding in these systems plays a role too. Data suggest that complete removal of surface functionalities would lead to a greater total surface area and higher micropore volume. 相似文献
7.
Purification and reversible immobilization of d-amino acid oxidase from Trigonopsis variabilis could be simultaneously accomplished by hydrophobic interaction on Phenyl Sepharose CL-4B in the presence of 50 mM pyrophosphate buffer (pH 8.5). The presence of a high salt concentration of 2M, which is generally required for the hydrophobic interactions, was not essential for the hydrophobic immobilization. The
enzyme in free as well as immobilized form was optimally active between pH 7.0 and 9.0. The immobilized preparation could
be reused in a batch process for the conversion of d-amino acids to α-keto acids. When the activity of the preparation dropped below practical limits, the gel could be regenerated
by water wash and recharged with fresh crude extract from yeast. 相似文献
8.
Dirk Blö mker Stanislaus Maier-Paape Thomas Wanner 《Transactions of the American Mathematical Society》2008,360(1):449-489
We consider the dynamics of a nonlinear partial differential equation perturbed by additive noise. Assuming that the underlying deterministic equation has an unstable equilibrium, we show that the nonlinear stochastic partial differential equation exhibits essentially linear dynamics far from equilibrium. More precisely, we show that most trajectories starting at the unstable equilibrium are driven away in two stages. After passing through a cylindrical region, most trajectories diverge from the deterministic equilibrium through a cone-shaped region which is centered around a finite-dimensional subspace corresponding to strongly unstable eigenfunctions of the linearized equation, and on which the influence of the nonlinearity is surprisingly small.
This abstract result is then applied to explain spinodal decomposition in the stochastic Cahn-Hilliard-Cook equation on a domain . This equation depends on a small interaction parameter , and one is generally interested in asymptotic results as . Specifically, we show that linear behavior dominates the dynamics up to distances from the deterministic equilibrium which can reach with respect to the -norm.
9.
Stanislaus Maier-Paape Reiner Lauterbach 《Transactions of the American Mathematical Society》2000,352(7):2937-2991
Recently it has been observed, that perturbations of symmetric ODE's can lead to highly nontrivial dynamics. In this paper we want to establish a similar result for certain nonlinear partial differential systems. Our results are applied to equations which are motivated from chemical reactions. In fact we show that the theory applies to the Brusselator on a sphere. To be more precise, we consider solutions of a semi-linear parabolic equation on the 2-sphere. When this equation has an axisymmetric equilibrium , the group orbit of (under rotations) gives a whole (invariant) manifold of equilibria. Under generic conditions we have that, after perturbing our equation by a (small) -equivariant perturbation, persists as an invariant manifold . However, the flow on is in general no longer trivial. Indeed, we find slow dynamics on and, in the case (the tetrahedral subgroup of ), we observe heteroclinic cycles. In the application to chemical systems we would expect intermittent behaviour. However, for the Brusselator equations this phenomenon is not stable. In order to see it in a physically relevant situation we need to introduce further terms to get a higher codimension bifurcation.
10.
Todd Kapitula Stanislaus Maier-Paape 《Zeitschrift für Angewandte Mathematik und Physik (ZAMP)》1996,47(2):265-305
We consider the dynamics of the Ginzburg-Landau equation in a small neighborhood of a known pulse solution by studying a Poincaré map,P:
T
T
, where
T
is a section which is transverse to the pulse. Due to the fact that the Ginzburg-Landau equation possesses both a rotational symmetry and a spatial symmetry, we are able to conduct a detailed analytical study of this map in neighborhoods arbitrarily close to the pulse solution. Thus, we are able to complement the work of Holmes [8], who conducted an analytical study of the Poincaré map in a punctured neighborhood of the pulse. We find that the Poincaré map contains an invariant set itT, where is not necessarily a Cantor set of points, such thatP: is homeomorphic to a shift map on (at least) two symbols. Furthermore, we find that for eachm 1 the mapP
itm possesses a fixed point. Since is not necessarily a Cantor set, this is not immediately clear. Finally, we find that when the pulse solution is broken, for eachm1 there exist parameter values such that pulses possessingm maxima appear.On leave at the University of Utah during 1993/94. Supported by the DFG, Habilitationsstipendium Ma 1587/1-1. 相似文献