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31.
Sha MY Walton ID Norton SM Taylor M Yamanaka M Natan MJ Xu C Drmanac S Huang S Borcherding A Drmanac R Penn SG 《Analytical and bioanalytical chemistry》2006,384(3):658-666
Single-nucleotide polymorphisms (SNP) are the most common form of sequence variation in the human genome. Large-scale studies
demand high-throughput SNP genotyping platforms. Here we demonstrate the potential of encoded nanowires for use in a particles-based
universal array for high-throughput SNP genotyping. The particles are encoded sub-micron metallic nanorods manufactured by
electroplating inert metals such as gold and silver into templates and releasing the resulting striped nanoparticles. The
power of this technology is that the particles are intrinsically encoded by virtue of the different reflectivity of adjacent
metal stripes, enabling the generation of many thousands of unique encoded substrates. Using SNP found within the cytochrome
P450 gene family, and a universal short oligonucleotide ligation strategy, we have demonstrated the simultaneous genotyping
of 15 SNP; a format requiring discrimination of 30 encoded nanowires (one per allele). To demonstrate applicability to real-world
applications, 160 genotypes were determined from multiplex PCR products from 20 genomic DNA samples. 相似文献
32.
The composition of natural ferrihydrite varies considerably, especially in terms of aluminum and silicon substitution. This work examines the influence of aluminum content on the redox reactivity of ferrihydrite nanoparticles as determined by kinetic studies of the reductive dissolution of the particles by hydroquinone. Transition state theory applied to variable-temperature experiments is used to measure the activation enthalpy and entropy. The presence of small amounts of aluminum (0-2.1 mol % substitution) causes a decrease in deltaH++ and an increase in deltaS++, resulting in an overall increase in reactivity. 相似文献
33.
Lejonthun LS Andersson PU Någård MB Pettersson JB 《The journal of physical chemistry. B》2006,110(46):23497-23501
The kinetics of chlorine interactions with ice at temperatures between 103 and 165 K have been studied using molecular beam techniques. The Cl(2) trapping probability is found to be unity at thermal incident energies, and trapping is followed by rapid desorption. The residence time on the surface is less than 25 microg at temperatures above 135 K and approaches 1 s around 100 K. Rate constants for desorption are determined for temperatures below 135 K. The desorption kinetics follow the Arrhenius equation, and activation energies of 0.24 +/- 0.03 and 0.31 +/- 0.01 eV, with corresponding preexponential factors of 10(12.08+/-1.19) and 10(16.52+/-0.38) s(-1), are determined. At least two different Cl(2) binding sites are concluded to exist on the ice surface. The observed activation energies are likely to be the Cl(2)-ice binding energies for these states, and the Cl(2)-surface interactions are concluded to be stronger than earlier theoretical estimates. The surface coverage of Cl(2) on ice under stratospheric conditions is estimated to be negligible, in agreement with earlier work. 相似文献
34.
K. Firoz Babu M. Anbu Kulandainathan Ioannis Katsounaros Liza Rassaei Andrew D. Burrows Paul R. Raithby Frank Marken 《Electrochemistry communications》2010,12(5):632-635
For the case of the commercially available metal-organic framework (MOF) structure BasoliteTM F300 or Fe(BTC) with BTC = benzene-1,3,5-tricarboxylate, it is shown that the Fe(III/II) electrochemistry is dominated by reductive dissolution rather than ion insertion (which in marked contrast is dominating the behaviour of Fe(III/II) open framework processes in Prussian blues). Solid Fe(BTC) immobilised onto graphite or platinum working electrodes is investigated and it is shown that well-defined and reversible Fe(III/II) reduction responses occur only on platinum and in the presence of aqueous acid. The process is shown to follow a CE-type mechanism involving liberation of Fe(III) in acidic media, in particular for high concentrations of acid. Effective electrocatalysis for the oxidation of hydroxide to O2 (anodic water splitting) is observed in alkaline aqueous media after initial cycling of the potential into the reduction potential zone. A mechanism based on a MOF-surface confined hydrous iron oxide film is proposed. 相似文献
35.
36.
Robert W. Penn 《Journal of Polymer Science.Polymer Physics》1966,4(4):559-569
The dynamic mechanical properties of poly-4-methylpentene-1 have been measured in torsion in the temperature range from 25 to 160°C. at frequencies from 10?3 to 10 cps. Two transitions are found. The first, with a peak at 40°C. at 1 cps, appears as a normal glass transition. A broad high temperature peak appears at 130°C. The dynamic compliance-frequency data can be superposed by the conventional method of reduced variables for temperatures up to 100°C. The temperature dependence of the shift factors follows the WLF equation. Above this temperature, superposition can be achieved by applying horizontal and vertical shifts to both components of the dynamic compliance. When the vertical shift is permitted, the range of applicability of the WLF equation is extended to 160°C. 相似文献
37.
M. Kirk Green Sharron G. Penn Carlito B. Lebrilla 《Journal of the American Society for Mass Spectrometry》1995,6(12):1247-1251
Gas-phase noncovalently bound complexes are probed by hydrogen/deuterium exchange. The complexes, composed of a protonated amino acid and a monosaccharide, are investigated to observe the effects of complexation on the rates of exchange. Rate constants are determined and compared for complexed and uncomplexed amino acids. The overall rate constant, which corresponds to exchange of a specific number of hydrogens, is deconvoluted to yield site-specific rate constants. Complexation of amino acids with saccharides significantly decreases the rate constants of the exchange. Results of molecular orbital calculations are provided to explain the decrease in the rates. 相似文献
38.
The performance of a free electron laser (FEL) using a low-power extreme ultraviolet (EUV) pulse as an input seed is investigated. The parameters are appropriate for 30 nm seeds produced from high-power Ti:Sapphire pulses using high harmonic generation schemes. It is found that, for reasonable beam parameters, robust FEL performance can be obtained. Both time-independent and time-dependent simulations are performed for varying system parameters using the GENESIS simulation code. A comparison is made with a two-stage harmonic FEL that is seeded by a high-power Ti:Sapphire pulse. 相似文献
39.
Muon cooling is a critical component of the proposed muon collider and neutrino factory. Previous studies of cooling channels have tracked single muons through the channel, which requires many particles for good statistics and does not lend itself to an understanding of channel dynamics. In this paper, a system of moment equations are derived which captures the major aspects of cooling: interactions with material and acceleration by radio frequency (rf) cavities. A general analysis of solenoid lattice types compares well with prior simulations and indicates new directions for study. 相似文献
40.
The total energy distribution (TED) of field-emitted electrons from an adsorbate-covered metal surface is studied within the framework of the Anderson Hamiltonian, but taking overcompleteness of states into account. The correct asymptotic behavior of the adsorbate wavefunction, postulated in the previous work, is now established, and a numerical correction factor (~15) to the adsorbate induced current density is obtained. 相似文献