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991.
Lihui Yang Genshui Wang Chaoliang Mao Yuanyuan Zhang Ruihong Liang Caroline Soyer Denis Rmiens Xianlin Dong 《Journal of Crystal Growth》2009,311(17):4241-4246
Highly (1 1 0)- and (1 0 0)-oriented LaNiO3 (LNO) thin films were successfully grown on Si (1 0 0) substrate using radio frequency (RF) magnetron sputtering at room temperature (RT). Effects of oxygen partial pressures on the orientation, film composition, surface morphology, and electrical properties of the films were investigated. The nearly complete (1 0 0) orientation was first achieved with oxygen partial pressure beyond 15% in the sputtering gas. The preferred (1 0 0) orientation of growing films is determined by uniform distribution of Ni3+ and La/Ni ratio in the films caused by oxygen during sputtering, as well as the lowest surface energy of the films in the crystalline process. LNO films with controlled orientation have low resistivity of 7.0×10−6 Ω m which is a good basis for integrating ferroelectric capacitors. 相似文献
992.
993.
994.
Whelan CM Gatti F Leigh DA Rapino S Zerbetto F Rudolf P 《The journal of physical chemistry. B》2006,110(34):17076-17081
The coverage-dependent adsorption on Au(111) of a fumaramide [2]rotaxane and its components, a benzylic amide macrocycle and a fumaramide thread, is studied using high-resolution electron energy loss spectroscopy (HREELS). Up to monolayer coverage, the relative intensity of out-of-plane to in-plane phenyl ring vibrational modes indicates that the macrocycle adopts an orientation with the phenyl rings largely parallel to the surface. The formation of a chemisorption bond is evidenced by the presence of a Au-O stretching vibration. In contrast, the thread shows no evidence of chemisorption or a preferential orientation. The introduction of the thread into the macrocycle partly disrupts the film order so that the resulting chemisorbed rotaxane shows intermediate behavior with a preferential orientation up to 0.5 ML coverage. A decrease in film order and the absence of a preferred molecular orientation is observed for all three molecules at multilayer coverages. The spectral differences are addressed by molecular dynamics simulations in terms of the mobility of the phenyls of the three molecules on Au(111). 相似文献
995.
Marquardsen T Hofmann M Hollander JG Loch CM Kiihne SR Engelke F Siegal G 《Journal of magnetic resonance (San Diego, Calif. : 1997)》2006,182(1):55-65
NMR based ligand screening is becoming increasingly important for the very early stages of drug discovery. We have proposed a method that makes highly efficient use of a single sample of a scarce target, or one with poor or limited solubility, to screen an entire compound library. This comparative method is based on immobilizing the target for the screening procedure. In order to support the method, a dual cell, flow injection probe with a single receiver coil has been constructed. The flow injection probe has been mated to a single high performance pump and sample handling system to enable the automated analysis of large numbers of compound mixes for binding to the target. The probe, having an 8 mm 1H/2H dual tuned coil and triple axis gradients, is easily shimmed and yields NMR spectra of comparable quality to a standard 5 mm high-resolution probe. The lineshape in the presence of a solid support is identical to that in glass NMR tubes in a 5 mm probe. Control spectra of each cell are identical and well separated, while ligand binding in a complex mixture can be readily detected in 20-30 min, thus paving the way for use of the probe for actual drug discovery efforts. 相似文献
996.
Caroline Lambert-Mauriat Vincent Oison Lama Saadi Khalifa Aguir 《Surface science》2012,606(1-2):40-45
The gas response of tungsten trioxide (WO3) based sensors strongly depends on the surface properties. Reconstructed surfaces and oxygen point defects at the surface of the monoclinic WO3 are studied using a self-consistent scheme based on first-principle. The oxygen vacancy is found to be the predominant defect independently of the oxygen partial pressure. Indeed, under rich oxygen atmosphere the formation enthalpies are found to be 1.45 eV in LDA (1.28 eV in GGA) for the oxygen vacancy instead of 2.70 eV (2.42 eV) for the oxygen adatom. When the oxygen partial pressure is lowered, the oxygen vacancy formation enthalpy decreases and becomes exothermic under very O-poor condition (? 1.65 eV in LDA and ? 1.36 eV in GGA). On the other hand, the formation enthalpy of an oxygen adatom rises. Finally, the oxygen vacancy formation acts as a n-doping by introducing negative charge carriers at the bottom of the conduction band. All these results can be very helpful in order to explain the electrical resistivity measurements. 相似文献
997.
Caroline Poock Prof. Dr. Markus Kalesse 《Chemistry (Weinheim an der Bergstrasse, Germany)》2021,27(5):1615-1619
The first total synthesis of halioxepine is accomplished using a 1,4-addition for constructing the quaternary center at C10 and a halo etherification for the generation of the tertiary ether at C7. The correct structure of halioxepine was determined by assembling different enantiomeric building blocks and by changing the relative configuration between C10 and C15. 相似文献
998.
Abe F Amidei D Apollinari G Atac M Auchincloss P Baden AR Bamberger A Barbaro-Galtieri A Barnes VE Bedeschi F Behrends S Belforte S Bellettini G Bellinger J Bensinger J Beretvas A Berge JP Bertolucci S Bhadra S Binkley M Blair R Blocker C Booth AW Brandenburg G Brown D Buckley E Byon A Byrum KL Campagnari C Campbell M Carey R Carithers W Carlsmith D Carroll JT Cashmore R Cervelli F Chadwick K Chiarelli G Chinowsky W Cihangir S Clark AG Connor D Contreras M Cooper J Cordelli M Crane D Curatolo M 《Physical review D: Particles and fields》1990,41(5):1717-1721
999.
Lenz P Ajo-Franklin CM Boxer SG 《Langmuir : the ACS journal of surfaces and colloids》2004,20(25):11092-11099
A simple and practical method for patterning supported lipid bilayers on poly(dimethylsiloxane) is presented. By using electron microscopy grids to laterally control the extent of plasma oxidation, the substrate is partitioned into regions of different hydrophilicities. Addition of vesicles then results in the spontaneous formation of lipid bilayers and monolayers side-by-side on the surface, separated by regions that contain no lipid and/or a region with adhering vesicles. By using millimeter-sized plastic masks we are able to control the formation of these lipid structures on macroscopic patches by simply varying the plasma-cleaning time. For the first time, we are able to influence, in a controlled fashion, the chemical composition of a substrate in such a way that it supports fluid lipid monolayers, rejects lipid adhesion, adsorbs intact lipid vesicles, or supports fluid bilayers. 相似文献
1000.
Dr. Florian M. Wisser Mathis Duguet Quentin Perrinet Dr. Ashta C. Ghosh Marcelo Alves-Favaro Yorck Mohr Chantal Lorentz Dr. Elsje Alessandra Quadrelli Prof. Dr. Regina Palkovits Dr. David Farrusseng Dr. Caroline Mellot-Draznieks Dr. Vincent de Waele Dr. Jérôme Canivet 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2020,132(13):5154-5160
The molecular-level structuration of two full photosystems into conjugated porous organic polymers is reported. The strategy of heterogenization gives rise to photosystems which are still fully active after 4 days of continuous illumination. Those materials catalyze the carbon dioxide photoreduction driven by visible light to produce up to three grams of formate per gram of catalyst. The covalent tethering of the two active sites into a single framework is shown to play a key role in the visible light activation of the catalyst. The unprecedented long-term efficiency arises from an optimal photoinduced electron transfer from the light harvesting moiety to the catalytic site as anticipated by quantum mechanical calculations and evidenced by in situ ultrafast time-resolved spectroscopy. 相似文献