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1.
Feng Ji Paul W. Percival Jean-Claude Brodovitch Brenda Addison-Jones Stanislaw Wlodek 《Hyperfine Interactions》1994,87(1):853-858
Muonium adds to allyl chloride, CH2=CHCH2Cl, to form two radicals: MuCH2CHCH2Cl (main product) and CH2CHMuCH2Cl (minor product). Both radicals were fully characterized bySR andLCR. In the main product, the LCR lines due to the35Cl and37Cl nuclei were observed. Also, the temperature dependence of various hyperfine coupling constants (hfc) indicates that both Mu and Cl eclipse the unpaired electronp
2-orbital in the minimum energy conformation. For the fragment-CH2Cl, the presence of Mu in the-position is found to affect significantly the hfc of Cl in the-position; an internal rotational barrier of 12 kJ mol–1 was estimated using a simpleV
2 torsional potential. 相似文献
2.
Martina Schwager Emil Roduner Ivan D. Reid Paul W. Percival Jean-Claude Brodovitch Stanislaw Wlodek Robert F. Marzke 《Hyperfine Interactions》1994,87(1):859-864
SR spectra of the ethyl radical adsorbed on porous silica were observed in transverse and in longitudinal magnetic fields in the temperature range 190–298 K. The line widths reflect the dynamic partial averaging of the hyperfine anisotropy due to reorientation and surface diffusion. 相似文献
3.
Abstract— L5178Y-R (LY-R) and L5178Y-S (LY-S) cells differ in sensitivity to UVC radiation (D0 : 2.8 and 9.0 J/m2 respectively, for cells exposed in Fischer's medium). We used these cells and a DNA unwinding technique in conjunction with 1-β-D-arabinosyl cytosine to determine DNA strand breaks accumulating as a result of enzymatic incision during DNA repair. Following UVC exposure DNA strand break accumulation was observed in LY-S cells but not in LY-R cells. The repair defect in LY-R cells is accompanied by a delayed recovery of [3 H]thymidine incorporation. 相似文献
4.
Zawadzki W 《Physical review letters》2007,99(17):179701; author reply 179702
5.
Benjamin A. Ellingson Matthew T. Geballe Stanislaw Wlodek Christopher I. Bayly A. Geoffrey Skillman Anthony Nicholls 《Journal of computer-aided molecular design》2014,28(3):289-298
Several submissions for the SAMPL4 hydration free energy set were calculated using OpenEye tools, including many that were among the top performing submissions. All of our best submissions used AM1BCC charges and Poisson–Boltzmann solvation. Three submissions used a single conformer for calculating the hydration free energy and all performed very well with mean unsigned errors ranging from 0.94 to 1.08 kcal/mol. These calculations were very fast, only requiring 0.5–2.0 s per molecule. We observed that our two single-conformer methodologies have different types of failure cases and that these differences could be exploited for determining when the methods are likely to have substantial errors. 相似文献
6.
Wlodek Zawadzki 《Solid State Communications》1985,56(1):43-46
Energies of resonant polarons related to interaction of inversion electrons in GaAs with optic phonons in the presence of a magnetic field are calculated and compared with recent cyclotron resonance measurements on a GaAs-GaAlAs heterostructure. The nonparabolocity of the conduction band is accounted for in the triangular potential approximation. The screening of polar interaction is neglected. Using an intensity of the confining electric field as a fitting parameter a very good agreement between the theory and the experiment is obtained. 相似文献
7.
An ellipsometer with 3μm×5μm spot size constructed with a single focusing and imaging element is used to measure the layer number of exfoliated graphene on glass and expitaxial graphene on SiC. Ellipsometric sensitivity to graphene layer number increases with decreasing layer number and decreasing substrate refractive index. Single-atomic-layer sensitivity has been achieved. High spatial resolution imaging and ellipsometry is useful for rapid characterization of epitaxially grown graphene films. 相似文献
8.
A Merck molecular force field classical potential combined with Poisson-Boltzmann electrostatics (MMFF/PB) has been used to estimate the binding free energy of seven guest molecules (six tertiary amines and one primary amine) into a synthetic receptor (acyclic cucurbit[4]uril congener) and two benzimidazoles into cyclic cucurbit[7]uril (CB[7]) and cucurbit[8]uril (CB[8]) hosts. In addition, binding enthalpies for the benzimidazoles were calculated with density functional theory (DFT) using the B3LYP functional and a polarizable continuum model (PCM). Although in most cases the MMFF/PB approach returned reasonable agreements with the experiment (±2 kcal/mol), significant, much larger deviations were reported in the case of three host-guest pairs. All four binding enthalpy predictions with the DFT/PCM method suffered 70% or larger deviations from the calorimetry data. Results are discussed in terms of the molecular models used for guest-host complexation and the quality of the intermolecular potentials. 相似文献
9.
Ji Li Zhuying Wang Ignacy Gryczynski Wlodek Mandecki 《Analytical and bioanalytical chemistry》2010,398(5):1993-2001
The aim of this study is to improve assay sensitivity in common solid-phase bioassay configurations as the result of using
silver nanoparticles. The solid phase was provided by numerically indexed, silicon-based electronic chips, microtransponders
(p-Chips) that have previously been used in multiplexed assays. Assay configurations investigated included an ELISA-type immunoassay
and a DNA hybridization assay. The surface of p-Chips was derivatized with the silver island film (SIF) and a polymer, and
then characterized with AFM and SEM. Silver nanoparticle sizes were in the range of 100 to 200 nm. Four fluorophores were
tested for fluorescence enhancement; namely, green fluorescent protein, phycoerythrin, Cy3 and Alexa Fluor 555. We consistently
observed significant fluorescence enhancement and sensitivity improvement in the p-Chip-based assays: the sensitivity in the
cytokine IL-6 immunoassay was 4.3 pg/ml, which represented a 25-fold increase over the method not involving a SIF; and 50 pM
in the hybridization assay, a 38-fold increase. The greatest enhancement was obtained for p-Chip surfaces derivatized first
with the polymer and then coated with SIF. In conclusion, we show that the SIF-p-Chip-based platform is a highly sensitive
method to quantify low-abundance biomolecules in nucleic acid-based assays and immunoassays. 相似文献
10.
Cronin-Hennessey D Kwon Y Lyon AL Thorndike EH Jessop CP Mariske H Perl ML Savinov V Ugolini D Zhou X Coan TE Fadeyez V Maravin Y Narsky I Stroynowski R Ye J Wlodek T Artuso M Ayad R Boulahouache C Bukin K Dambasuren E Karamnov S Kopp S Majumder G Moneti GC Mountain R Schuh S Skwarnicki T Stone S Viehauser G Wang JC Wolf A Wu J Csorna SE Danko I McLean KW Márka S Xu Z Godang R Kinoshita K Lai IC Schrenk S Bonvicini G Cinabro D Perera LP Zhou GJ Eigen G Lipeles E Sharma V 《Physical review letters》2000,85(3):515-519
We have studied charmless hadronic decays of B mesons into two-body final states with kaons and pions and observe three new processes with the following branching fractions: beta(B-->pi(+)pi(-)) = (4.3(+1. 6)(-1.4)+/-0.5)x10(-6), beta(B-->K(0)pi(0)) = (14.6(+5.9+2.4)(-5.1-3. 3))x10(-6), and beta(B-->K(+)/-pi(0)) = (11.6(+3.0+1.4)(-2.7-1.3))x10(-6). We also update our previous measurements for the decays B-->K(+)/-pi(-/+) and B+/--->K(0)pi(+/-). 相似文献