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81.
82.
Ming-Yao Cheng Ching-Yeh Shiau Ping-Hung Lin Jen-Chen Chang 《Journal of Solid State Electrochemistry》2011,15(4):773-779
In this study, samaria-doped ceria (Sm0.2Ce0.8O1.9, SDC) thin film is deposited on the Ni-SDC support by employing the electrophoretic deposition technique. Various factors
are considered for the deposition of SDC films. The corresponding microstructure of the deposited SDC film is examined and
correlated to the electrochemical performance as a single-chamber solid oxide fuel cell (sc-SOFC). It is found that the microstructure
of the SDC film mainly relates to the particle size of SDC. After heat treatment, highly dense SDC film is obtained with the
deposition condition of 5 g L−1 of the SDC suspension (average grain size of SDC, 248 nm), 60 V as the applied potential, and the deposition time of 1 min
(18 μm in thickness). For the Ni-SDC/SDC/SSC cell, an open circuit potential of 0.92 V and peak power density of 155 mW cm−2 can be obtained at the furnace temperature of 500 °C. 相似文献
83.
Brubaker CE Messersmith PB 《Langmuir : the ACS journal of surfaces and colloids》2012,28(4):2200-2205
The natural world provides many examples of robust, permanent adhesive platforms. Synthetic adhesive interfaces and materials inspired by mussels of genus Mytulis have been extensively applied, and it is expected that characterization and adaptation of several other biological adhesive strategies will follow the Mytilus edulis model. These candidate species will be introduced, along with a discussion of the adhesive behaviors that make them attractive for synthetic adaptation. While significant progress has been made in the development of biologically inspired adhesive interfaces and materials, persistent questions, current challenges, and emergent areas of research will be also be discussed. 相似文献
84.
Grey JK Kim DY Donley CL Miller WL Kim JS Silva C Friend RH Barbara PF 《The journal of physical chemistry. B》2006,110(38):18898-18903
Fluorescence emission spectra were recorded for isolated polymer chains of the polyfluorene copolymer, F8BT [poly(9,9-di-n-octylfluorene-alt-benzothiadiazole)], at 298 and 20 K for two molecular weights (chain lengths). For long-chain F8BT at 298 K, the observed distribution of single-molecule emission maxima G(Emax) is bimodal, with peaks at approximately 2.35 eV ("blue") and approximately 2.25 eV ("red"). Previously, the red forms have been assigned to polymer chains that possess intrachain contacts, which lowers the local singlet exciton energy. At approximately 20 K, G(Emax) collapses into a single broad distribution centered at approximately 2.3 eV for long-chain F8BT. However, this distribution can be further divided into a high-energy edge that is dominated by the "blue" form, while the remainder of the distribution is composed of the "red" form. Low-molecular-weight F8BT samples emit exclusively from the blue form, and no shift in peak maxima with low temperature was observed. A Franck-Condon analysis reveals a decrease in emitting state displacements between spectra measured at 298 and 20 K, suggesting that temperature-induced structural displacements are responsible for the change in the bimodal emission. 相似文献
85.
John G. Bruno Maria P. Carrillo Taylor Phillips Carrie J. Andrews 《Journal of fluorescence》2010,20(6):1211-1223
A novel high-throughput screening method is described in which a family of DNA aptamers selected against E. coli outer membrane proteins (OMPs) is subjected to PCR in the presence of fluorophore-dUTP conjugates using Deep Vent® exo- polymerase. The fluorophore-doped aptamers and their complementary strands are then heated to render them single-stranded and screened in filter well microtiter plates for fluorescence resonance energy transfer (FRET) assay potential. Using this system, a superior competitive FRET-aptamer designated EcO 4R was identified and the location of its putative binding pocket was determined by individually testing FRET potential in each of the secondary loop structures. By labeling the binding pocket with Alexa Fluor (AF) 647 and binding the aptamer to heavily Black Hole Quencher-3 (BHQ-3)-labeled E. coli bacteria, detection of as few as 30 live unlabeled E. coli per ml was achieved in a competitive displacement FRET assay format. The far red fluorescence emission enables detection in largely blue-green autofluorescent matrices. In addition, the competitive transfer of AF 647-EcO-4R aptamer to unlabeled E. coli cells after a 15 min equilibration period was verified by fluorescence microscopy. The present study also demonstrated that high aptamer affinity is not well correlated with competitive FRET potential. 相似文献
86.
Anthony S. Stender Lindsay A. Giem Matt C. Bunte Carrie L. Burns Lindsay D. Odom Diane S. Fitzpatrick Christopher J. Biorn Eugene T. Smith 《The Chemical Educator》2000,5(6):321-323
A laboratory exercise, the analysis of arsenic in drinking water by graphite furnace atomic absorption spectroscopy (GFAA), is presented for use in an undergraduate instrumental methods course. The purpose of this GFAA exercise is to expose students to a practical and commonly used application, to provide students with hands-on experience with the instrument, and to reinforce concepts taught in the classroom. Students safely analyze a real-world sample containing an analyte in the parts-per-billion concentration range. 相似文献
87.
Brandon J. O'Neill David H. K. Jackson Dr. Anthony J. Crisci Carrie A. Farberow Fengyuan Shi Dr. Ana C. Alba‐Rubio Dr. Junling Lu Dr. Paul J. Dietrich Dr. Xiangkui Gu Dr. Christopher L. Marshall Prof. Peter C. Stair Dr. Jeffrey W. Elam Dr. Jeffrey T. Miller Prof. Fabio H. Ribeiro Prof. Paul M. Voyles Prof. Jeffrey Greeley Prof. Manos Mavrikakis Prof. Susannah L. Scott Prof. Thomas F. Kuech Prof. James A. Dumesic 《Angewandte Chemie (International ed. in English)》2013,52(51):13808-13812
Atomic layer deposition (ALD) of an alumina overcoat can stabilize a base metal catalyst (e.g., copper) for liquid‐phase catalytic reactions (e.g., hydrogenation of biomass‐derived furfural in alcoholic solvents or water), thereby eliminating the deactivation of conventional catalysts by sintering and leaching. This method of catalyst stabilization alleviates the need to employ precious metals (e.g., platinum) in liquid‐phase catalytic processing. The alumina overcoat initially covers the catalyst surface completely. By using solid state NMR spectroscopy, X‐ray diffraction, and electron microscopy, it was shown that high temperature treatment opens porosity in the overcoat by forming crystallites of γ‐Al2O3. Infrared spectroscopic measurements and scanning tunneling microscopy studies of trimethylaluminum ALD on copper show that the remarkable stability imparted to the nanoparticles arises from selective armoring of under‐coordinated copper atoms on the nanoparticle surface. 相似文献
88.
Yuo-Hsien Shiau 《Solid State Communications》2006,139(6):278-283
A cross-correlation matrix applied for restoring the doping profile in an n+-n−-n-n+ device was reported recently [Y.-H. Shiau, Solid-State Electron. 50 (2006) 191]. In this paper we will show that this statistical method is very useful for detecting the dynamical processes embedded in semiconductor devices. In addition, extraction of nonuniform fluctuations hidden in this wide-gap semiconductor device could be helpful for clarifying the previous studies on several competing instabilities in InSb at 77 K [A. ?enys, G. Lasiene, K. Pyragas, Solid-State Electron. 35 (1992) 975; H. Ito, Y. Ueda, Phys. Lett. A 280 (2001) 312]. A general discussion about the application of the cross-correlation matrix to other pattern-forming systems is also given in the present study. 相似文献
89.
V. L. Spate J. S. Morris T. A. Nichols C. K. Baskett M. M. Mason T. L. Horsman P. L. Horn-Ross A. C. Shiau I. R. McDougall 《Journal of Radioanalytical and Nuclear Chemistry》1998,236(1-2):71-77
The literature on the relationship between diet and thyroid cancer (TC) risk and the higher incidence of TC among Asian immigrants
to the US compared to second and third generation subgroups has prompted epidemiologists to hypothesize that increased levels
of iodine consumption may be associated with TC risk, particularly among persons with a history of clinical or subclinical
thyroid dysfunction. At the University of Missouri Research Reactor (MURR), we have applied epiboron neutron activation analysis
to investigate human nails as a dietary monitor for iodine. Preliminary studies have indicated a positive correlation between
dietary iodine intake and the concentration of iodine in toenails. However, these studies are confounded by high iodine levels
(up to 30 ppm) in approximately 5% of the nails studied. We hypothesize that, in the subjects we have studied, the high iodine
levels may be due to iodine-containing medications, in particular contrast-agents containing iopamidol. This paper will report
on longitudinal studies using contrast agent subjects who were followed-up for almost two years compared to a longitudinal
control and a population mean. Based on this study, we suggest that iodine-containing contrast agents contaminate nail samples
via non-specific binding in the short term followed by incorporation in the nail as a result of absorption. 相似文献
90.
Sammond DW Bosch DE Butterfoss GL Purbeck C Machius M Siderovski DP Kuhlman B 《Journal of the American Chemical Society》2011,133(12):4190-4192
The de novo design of protein-binding peptides is challenging because it requires the identification of both a sequence and a backbone conformation favorable for binding. We used a computational strategy that iterates between structure and sequence optimization to redesign the C-terminal portion of the RGS14 GoLoco motif peptide so that it adopts a new conformation when bound to Gα(i1). An X-ray crystal structure of the redesigned complex closely matches the computational model, with a backbone root-mean-square deviation of 1.1 ?. 相似文献