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161.
Moraes FC Lima RS Segato TP Cesarino I Cetino JL Machado SA Gomez F Carrilho E 《Lab on a chip》2012,12(11):1959-1962
This communication reports a promising platform for rapid, simple, direct, and ultrasensitive determination of serotonin. The method is related to integration of vertically aligned single-walled carbon nanotubes (SWCNTs) in electrochemical microfluidic devices. The required microfabrication protocol is simple and fast. In addition, the nanomaterial influenced remarkably the obtained limit-of-detection (LOD) values. Our system achieved a LOD of 0.2 nmol L(-1) for serotonin, to the best of our knowledge one of the lowest values reported in the literature. 相似文献
162.
Emine Kayhan Ravi Mohan Prasad Dr. Alexander Gurlo Dr. Oktay Yilmazoglu Dr. Jörg Engstler Dr. Emanuel Ionescu Songhak Yoon Prof. Dr. Anke Weidenkaff Prof. Dr. Jörg J. Schneider 《Chemistry (Weinheim an der Bergstrasse, Germany)》2012,18(47):14996-15003
Low‐layered, transparent graphene is accessible by a chemical vapor deposition (CVD) technique on a Ni‐catalyst layer, which is deposited on a <100> silicon substrate. The number of graphene layers on the substrate is controlled by the grain boundaries in the Ni‐catalyst layer and can be studied by micro Raman analysis. Electrical studies showed a sheet resistance (Rsheet) of approximately 1435 Ω per □, a contact resistance (Rc) of about 127 Ω, and a specific contact resistance (Rsc) of approximately 2.8×10?4 Ω cm2 for the CVD graphene samples. Transistor output characteristics for the graphene sample demonstrated linear current/voltage behavior. A current versus voltage (Ids–Vds) plot clearly indicates a p‐conducting characteristic of the synthesized graphene. Gas‐sensor measurements revealed a high sensor activity of the low‐layer graphene material towards H2 and CO. At 300 °C, a sensor response of approximately 29 towards low H2 concentrations (1 vol %) was observed, which is by a factor of four higher than recently reported. 相似文献
163.
We study the structure and electronic properties of (TiO2)(2-10) clusters by using basin hopping based on density functional theory, combined with many-body perturbation theory. We show that in photoemission experiments performed on anions isomers with high electron affinity are selectively observed rather than those with the lowest energy. These isomers possess a highly reactive Ti3+ site. The selectivity for highly reactive clusters may be exploited for applications in catalysis. 相似文献
164.
165.
Emanuel Postolache D. K. Powell G. Popov Ram C. Rai M. Greenblatt J. W. Brill 《Solid State Sciences》2000,2(8)
We have measured Young's modulus (using a vibrating reed technique) and the specific heat (using ac calorimetry) on the same crystals of α′-NaV2O5 at its Tc=34 K magnetic phase transition. Both properties exhibit large, unsymmetrical, and sample-dependent anomalies. While the specific heat results suggest tricritical behavior of the transition, large fluctuation effects are observed in the modulus above Tc. Fits of the modulus in terms of the specific heat, entropy, and free energy suggest that fluctuations are strongly stress- and sample-dependent. 相似文献
166.
A spatially and temporally local analysis is provided for unsteady, oblique shock waves, in which the flow is assumed to
be two-dimensional or axisymmetric. Three unsteady parameters, in a laboratory frame, are viewed as the known independent
variables. These are the upstream Mach number, the shock Mach number, and the angle of the shock relative to the instantaneous
upstream velocity. Other steady and unsteady parameters, such as the velocity turn angles and downstream Mach numbers, are
evaluated in closed form, in terms of these three quantities. Trends are assessed, and a sensitivity analysis is provided.
It is suggested that the theory may find application in converting a shock capturing algorithm, at an early time during the
computational process, into a shock fitting algorithm.
Received 30 April 1999 / Accepted 29 November 1999 相似文献
167.
168.
Emanuel Sperner 《Archiv der Mathematik》1948,1(1):9-12
Ohne ZusammenfassungÜber diesen Gegenstand habe ich zum ersten Mal im November 1943 in Bukarest und Timisoara Vorträge gehalten. 相似文献
169.
Emanuel Czuber 《Monatshefte für Mathematik》1894,5(1):267-286
Ohne Zusammenfassung 相似文献
170.
The reaction of bis(6-diphenylphosphinoacenapht-5yl)mercury, (6-Ph2P-Ace-5-)2Hg, with [(CO)2RhCl]2 and PtCl2 proceeded with extrusion of mercury / mercury(I) chloride and provided the octahedral rhodium and platinum complexes (6-Ph2P-Ace-5-)2Rh(CO)Cl and (6-Ph2P-Ace-5-)2PtCl2, respectively. The reaction of the (6-diphenylphosphinoacenapht-5yl)stannane 6-Ph2P-Ace-5-SnBu3 with PdCl2 gave rise to tributyltin chloride and a dimeric arylpalladium chloride [(6-Ph2P-Ace-5-)PdCl]2 with a planar Pd2Cl2 core. Together with the previously known gold(III) complex cis- and trans-[R2Au][Cl], the newly prepared compounds were investigated by DFT calculations. The fully optimized gas-phase structure of [(6-Ph2P-Ace-5-)PdCl]2 gives rise to a bend Pd2Cl2 core featuring a Pd ··· Pd palladophilic interaction. The bonding situation was studied using a set of real-space bonding indicators (RSBIs) derived from the methods Atoms-In-Molecules (AIM), Electron Localizability Indicator (ELI-D) and Non-Covalent Interaction (NCI) index. 相似文献