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排序方式: 共有382条查询结果,搜索用时 15 毫秒
311.
Vasile-Dan Hodoroaba Steffi Rades Patrizia Borghetti Erik Ortel Thomas Wirth Sarai García Estíbaliz Gómez Miren Blanco Gabriele Alberto Gianmario Martra 《Surface and interface analysis : SIA》2020,52(12):829-834
The characteristics of TiO2 coatings can greatly influence their final performance in large-scale applications. In the present study, self-assembly of TiO2 nanoparticles (NPs) in multiple layers was selected as a deposition procedure on various substrates. For this, the main prerequisite constitutes the surface modification of both NPs and substrate with, for example, silane coupling agents. A set of functionalized TiO2 NPs has been produced by reaction with either (3-aminopropyl)triethoxysilane (APTES) or (3-aminopropyl)phosphonic acid (APPA) to functionalize the NP surface with free amino-groups. Then, the complementary functionalized NP set can be obtained from an aliquot of the first one, through the conversion of free surface amino groups to aldehydes by reaction with glutaraldehyde (GA). Several types of TiO2 NPs differing in size, shape, and specific surface area have been functionalized. Fourier-transform infrared spectroscopy (FTIR), thermogravimetric analysis (TGA), SEM/ energy-dispersive X-ray spectroscopy (EDS), XPS, Auger electron spectroscopy (AES), and Time-of-Flight (ToF)-SIMS analyses have been carried out to evaluate the degree of functionalization, all the analytical methods employed demonstrating successful functionalization of TiO2 NP surface with APTES or APPA and GA. 相似文献
312.
Wu W Wong KL Ali R Chen CY Cocke CL Frohne V Giese JP Raphaelian M Walch B Dörner R Mergel V Schmidt-Böcking H Meyerhof WE 《Physical review letters》1994,72(20):3170-3173
313.
Abstract An IR diode laser spectrometer can detect the enrichment of stable isotopes (13C [1] and 15N[2]) in tracer studies. However our system cannot detect differences of the natural abundances of these isotopes. This problem is not a principal limitation of the IR diode laser spectroscopy, but is inherent to our standard system. A new isotope ratio IR diode laser spectrometer has an accuracy high enough for most biological applications. Some advantages like flexibility in measuring different isotopes, insensitivity against other gases in the sample and price are correlated to this system. 相似文献
314.
V. I. Engelko H. Giese V. S. Kuznetsov G. A. Viazmenova S. Schalk 《Technical Physics》2002,47(3):350-356
An intense low-energy (15–20 keV) proton beam is focused in two stages: ballistic focusing is followed by magnetic compression. The beam is formed by an MAIS wide-aperture source, in which a plasma is generated by many discharge elements via a discharge over the polyethylene surface. In the presence of an external magnetic field, the beam turns out to be overneutralized by electrons coming from the cathode grids of the source and from the target. The maximal focusing efficiency (>70%) is observed within 10 μs after the pulse has been applied if the target is negatively biased. The degree of beam compression in terms of cross-sectional area is 1.6×103. The numerical simulation of the focusing agrees well with the results of measurement. 相似文献
315.
316.
Raja Shahid Ashraf Harald Hoppe Munazza Shahid Gerhard Gobsch Steffi Sensfuss Elisabeth Klemm 《Journal of polymer science. Part A, Polymer chemistry》2006,44(24):6952-6961
Novel copolymers consisting of the alternating push–pull comonomers fluorene and thieno[3,4‐b]pyrazine/quinoxaline were synthesized by a palladium‐catalyzed Suzuki cross‐coupling reaction in 60–80% yields. The structure of the deeply colored copolymers was confirmed with 1H and 13C NMR. All the new materials were characterized with spectroscopic and electrochemical methods. Bulk heterojunction organic solar cells based on some of the novel polymers in combination with the well‐known fullerene acceptor [6,6]‐phenyl C61–butyric acid methyl ester were fabricated, and their photovoltaic parameters were measured. © 2006 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 44: 6952–6961, 2006 相似文献
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320.
Janina Janisch Adrian Ruff Bernd Speiser Christian Wolff Jonas Zigelli Steffi Benthin Verena Feldmann Hermann A. Mayer 《Journal of Solid State Electrochemistry》2011,15(10):2083-2094
Cyclic voltammetry data recorded at disk macro- (millimeter dimension) and microelectrodes (10 and 100 μm) at various scan
rates are used to simultaneously determine the diffusion coefficient D of ferrocene (fc) and the electroactive surfaces A and/or radii r of the electrodes. A case study with three electrodes of different sizes in CH3CN- and propylene carbonate (PC)-based electrolytes shows the possibly large effect of incorrect D values. Diffusion coefficients of fc are determined for PC, CH3CN, CH2Cl2, DMF, and DMSO electrolytes and (except for PC) compared to those from pulse-gradient spin-echo nuclear magnetic resonance
experiments in the presence of supporting electrolyte in the respective deuterated solvents. The dependence of D
fc on solvent viscosity is shown to follow the Stokes–Einstein relation. 相似文献