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131.
Hamiltonian encoding (HE) methods have been used to understand mechanism in computational studies of laser controlled quantum
systems. This work studies the principles for extending such methods to extract control mechanisms from laboratory data. In
an experimental setting, observables replace the utilization of wavefunctions in computational HE. With laboratory data, HE
gives rise to a set of quadratic equations for the interfering transition amplitudes, and the solution to the equations reveals
the mechanistic pathways. The extraction of the mechanism from the system of quadratic equations raises questions of uniqueness
and solvability, even in the ideal case without noise. Symmetries are shown to exist in the quadratic system of equations,
which is generally overdetermined. Therefore, the mechanism is likely to be unique up to these symmetries. Numerical simulations
demonstrate the concepts on simple model systems. 相似文献
132.
Dr. James E. H. Day Dr. Swee Y. Sharp Dr. Martin G. Rowlands Dr. Wynne Aherne Dr. William Lewis Dr. S. Mark Roe Dr. Chrisostomos Prodromou Prof. Dr. Laurence H. Pearl Prof. Dr. Paul Workman Prof. Dr. Christopher J. Moody 《Chemistry (Weinheim an der Bergstrasse, Germany)》2010,16(34):10366-10372
A series of resorcylic acid macrolactones, analogues of the natural product radicicol has been prepared by chemical synthesis, and evaluated as inhibitors of heat shock protein 90 (Hsp90), an emerging attractive target for novel cancer therapeutic agents. The synthesis involves acylation of an ortho‐toluic acid dianion, esterification, followed by a ring‐closing metathesis to form the macrocycle. Subsequent manipulation of the protected hydroxymethyl side chain allows access to a range of new analogues following deprotection of the two phenolic groups. Co‐crystallization of one of the new macrolactones with the N‐terminal domain of yeast Hsp90 confirms that it binds in a similar way to the natural product radicicol and to our previous synthetic analogues, but that the introduction of the additional hydroxymethyl substituent appears to result in an unexpected change in conformation of the macrocyclic ring. As a result of this conformational change, the compounds bound less favorably to Hsp90. 相似文献
133.
Steenackers M Gigler AM Zhang N Deubel F Seifert M Hess LH Lim CH Loh KP Garrido JA Jordan R Stutzmann M Sharp ID 《Journal of the American Chemical Society》2011,133(27):10490-10498
A critical bottleneck for the widespread use of single layer graphene is the absence of a facile method of chemical modification which does not diminish the outstanding properties of the two-dimensional sp(2) network. Here, we report on the direct chemical modification of graphene by photopolymerization with styrene. We demonstrate that photopolymerization occurs at existing defect sites and that there is no detectable disruption of the basal plane conjugation of graphene. This method thus offers a route to define graphene functionality without degrading its electronic properties. Furthermore, we show that photopolymerization with styrene results in self-organized intercalative growth and delamination of few layer graphene. Under these reaction conditions, we find that a range of other vinyl monomers exhibits no reactivity with graphene. However, we demonstrate an alternative route by which the surface reactivity can be precisely tuned, and these monomers can be locally grafted via electron-beam-induced carbon deposition on the graphene surface. 相似文献
134.
The exploitation of singlet oxygen generating compounds as a means of targeted therapies drives the need to develop methods for assessing the efficacy of such compounds and their capacity for generating the reactive oxygen species. Degradation of diphenylisobenzofuran by singlet oxygen is widely used as a spectroscopic probe but its application can be problematic. An alternative detection strategy exploiting the electrochemical monitoring of the quencher concentration, by square wave voltammetry, has been shown to provide a more sensitive and flexible option that could be used to address the increasing interest in photosensitizing materials. 相似文献
135.
136.
We present what we believe to be the first implementation of a Fabry-Perot (FP) etalon using polymer cholesteric liquid-crystal mirrors. These polymer mirrors have each been fabricated onto a single substrate, which allows the FP cavity spacing to be only a few micrometers wide. For the experimental results presented, cavity lengths of 13.8 and 7.6 mum yield near-infrared free spectral ranges of 24.8 and 45.6 nm, respectively. The measured finesse of 14.31 is approaching the limitation imposed by the reflectivity of the mirrors. 相似文献
137.
John A. Berry Ann Prescott David W.A. Sharp John M. Winfield 《Journal of fluorine chemistry》1977,10(3):247-254
Rhenium and uranium hexafluorides oxidise elemental iodine in iodine pentafluoride at ambient temperature to give the I2+ cation. With UF6 an additional reaction occurs to give β-uranium pentafluoride as one product, β-UF5 is soluble in acetonitrile without disproportionation and is also formed from the reduction of UF6 by MeCN. Copper, cadmium, and thallium metals are oxidised by ReF6 in MeCN giving CuI, CdII, and TlI hexafluororhenates(V) but the reactions are complicated by reaction between ReF6 and the solvent. 相似文献
138.
139.
R. J. Roach E. A. Raymond J. R. Tyrer B. L. Sharp 《Optical and Quantum Electronics》1995,27(12):1457-1469
Information presented by other workers on fumes generated during high-power CO2 laser processing tends in most cases to be empirical and qualitative in nature, which has limited the significance of this data to real industrial applications. This paper reviews information on the nature of laser processing fumes and proposes a model for indexing the risk associated with the fumes from both plastics and metal materials processing. The index allows the risks from a specific laser processing system to be assessed and classified into one of three groups. Classification of the risk associated with particular fumes enables appropriate choices about the extraction and filtration system to be made. Application of this model highlights the risks involved in processing stainless steel, owing to the formation of Cr(vi). It also highlights the problems associated with processing Kevlar, polycarbonate, and polyamide. 相似文献
140.