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51.
Ramsay AJ Boyle SJ Kolodka RS Oliveira JB Skiba-Szymanska J Liu HY Hopkinson M Fox AM Skolnick MS 《Physical review letters》2008,100(19):197401
We propose and demonstrate the sequential initialization, optical control, and readout of a single spin trapped in a semiconductor quantum dot. Hole spin preparation is achieved through ionization of a resonantly excited electron-hole pair. Optical control is observed as a coherent Rabi rotation between the hole and charged-exciton states, which is conditional on the initial hole spin state. The spin-selective creation of the charged exciton provides a photocurrent readout of the hole spin state. 相似文献
52.
Boyle Cullen Liang Liang Romo-De-La-Cruz Cesar-Octavio Johnson Robert Chen Yun Prucz Jacky Cakmak Ercan Watkins Thomas R. Lara-Curzio Edgar Song Xueyan 《Journal of Sol-Gel Science and Technology》2018,85(3):712-722
Journal of Sol-Gel Science and Technology - We report on the influence of sintering gas atmosphere on the thermoelectric (TE) performance of Ca3Co4O9?+?δ ceramics made from... 相似文献
53.
Dr. Benjamin A. Chalmers Hui Xing Sevan Houston Dr. Charlotte Clark Dr. Sussan Ghassabian Dr. Andy Kuo Benjamin Cao Andrea Reitsma Cody‐Ellen P. Murray Dr. Jeanette E. Stok Dr. Glen M. Boyle Carly J. Pierce Stuart W. Littler Prof. David A. Winkler Prof. Paul V. Bernhardt Dr. Cielo Pasay Prof. James J. De Voss Prof. James McCarthy Prof. Peter G. Parsons Prof. Gimme H. Walter Prof. Maree T. Smith Prof. Helen M. Cooper Prof. Susan K. Nilsson Dr. John Tsanaktsidis Dr. G. Paul Savage Prof. Craig M. Williams 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2018,130(28):8491-8491
54.
Timothy P. Boyle Jonathan Coates Paul A. Keller Stephen G. Pyne David I. Rhodes 《Tetrahedron》2008,64(49):11270-11290
As part of a program investigating cyclic peptides with an internal aromatic hydrophobic scaffold as potential novel anti-bacterial agents, we explored the synthesis of simple tyrosine-based systems. These were prepared via key intermediates containing internal allylglycine and allyltyrosine residues for subsequent ring-closing metathesis reactions. Although the resulting anti-bacterial activity against Staphylococcus aureus was modest, this represents a novel and simple route to this class of compounds. One intermediate acyclic dipeptide precursor showed good activity against S. aureus with an MIC of 7.8 μg/mL. 相似文献
55.
56.
Benjamin A. Chalmers Hui Xing Sevan Houston Charlotte Clark Sussan Ghassabian Andy Kuo Benjamin Cao Andrea Reitsma Cody‐Ellen P. Murray Jeanette E. Stok Glen M. Boyle Carly J. Pierce Stuart W. Littler David A. Winkler Paul V. Bernhardt Cielo Pasay James J. DeVoss James McCarthy Peter G. Parsons Gimme H. Walter Maree T. Smith Helen M. Cooper Susan K. Nilsson John Tsanaktsidis G. Paul Savage Craig M. Williams 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2016,128(11)
57.
Kathleen E. Berg Jaclyn A. Adkins Sarah E. Boyle Charles S. Henry 《Electroanalysis》2016,28(4):679-684
Mn concentrations were determined using square‐wave cathodic stripping voltammetry (CSV) with inexpensive, stencil‐printed carbon ink electrodes generated on polypropylene transparency films. Using an optimized pH 5 ammonium acetate buffer and addition of 1,4‐benzoquinone, a detection limit as low as 500 nM (30 ppb) was achieved. Addition of 1,4‐benzoquinone improved peak potential reproducibility and height, while addition of 3.5 % w/w sodium chloride to the background solution approximately doubled the sensitivity (μA/ppm). Tolerance tests with interfering metals were conducted and the method was found to be resilient to chromium(VI), iron(III), magnesium(II), nickel(II), and zinc(II), but susceptible to aluminum(III), copper(II), iron(II), and lead(II) at concentration ratios at or below one. This technique was successfully used to measure Mn levels in yerba mate and green tea samples as an example application. 相似文献
58.
Jha SC Lorch M Lewis RA Archibald SJ Boyle RW 《Organic & biomolecular chemistry》2007,5(12):1970-1974
A calix[4]phyrin-(1,1,1,1) substituted with a 4-isothiocyanatophenyl group has been synthesised and used to attach the macrocycle to a solid support. The NCS group can also be used to further functionalise the calix[4]phyrin-(1,1,1,1) by reaction with amines and amino acids. Stability constants for anion binding by the calix[4]phyrin-(1,1,1,1) are reported and these show a clear ability to differentiate F(-) and HSO(4)(-) from Cl(-), Br(-), I(-) which can be detected by both NMR and UV-visible spectroscopy. 相似文献
59.
Boyle TJ Sewell RM Ottley LA Pratt HD Quintana CJ Bunge SD 《Inorganic chemistry》2007,46(5):1825-1835
The reaction of [Ti(mu-ONep)(ONep)3]2 (ONep = OCH2C(CH3)3) with a series of heterocyclic methanol derivatives [tetrahydrofurfuryl alcohol (H-OTHF), thiophene methanol (H-OTPM), or 2-pyridylcarbinol (H-OPy)-collectively termed H-OR*], led to the isolation of a novel family of OR*-substituted titanium alkoxide precursors. Independent of the initial stoichiometry for the H-OTHF reaction, a monosubstituted, dinuclear species was isolated as [(ONep)3Ti(muc-OTHF)]2 (1). For 1, each Ti was octahedrally (Oh) bound by three terminal ONep ligands, one bidentate bridging OTHF ligand (muc-OTHF), and an oxygen from the other muc-OTHF ligand. For the OTPM derivatives, the product was identified as [(ONep)3Ti(mu-OTPM)]2 (2). For this ligand, the soft S atom does not bind to the Ti but the O atom does act as a bridge between the two trigonal bipyramidal bound Ti metal centers. The OPy system yielded (OPy)2Ti(OR)2 independent of the OR and the stoichiometry used [OR = ONep (3), OCHMe2 (4), OCMe3 (5)]. For 3-5, the two OPy ligands chelate to the Oh-bound Ti metal center with two terminal OR ligands. Compounds 1-5 were fully characterized using a variety of analytical techniques. An initial investigation of the proposed chemical stability of the '(OPy)2Ti' moiety of 3-5 to alcoholysis exchange pathways involving (i) alkyl alcohols, (ii) aryl alcohols, (iii) substituted phenols, (iv) H-OR* derivatives, and (v) silanols proved successful through the isolation of a novel family of structurally characterized (OPy)2Ti(OR')2 (7-24) compounds. 相似文献
60.
Opium samples from four different locations and poppy straw from different plant varieties have been assayed using micellar capillary electrophoresis incorporating a sweeping technique. Individual alkaloids (morphine, codeine, papaverine, noscapine, thebaine, oripavine, reticuline and narceine) were quantitatively determined in the different samples by a validated capillary electrophoresis method. Unsupervised pattern recognition of the opium samples and the poppy straw samples using hierarchical cluster analysis (HCA) and principal component analysis (PCA), showed distinct clusters. Supervised pattern recognition using soft independent modelling of class analogy (SIMCA) was performed to show individual groupings and allow unknown samples to be classified according to the models built using the CZE assay results. 相似文献