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1.
Combined photochemical arylation, “nuisance effect” (SNAr) reaction sequences have been employed in the design of small arrays for immediate deployment in medium-throughput X-ray protein–ligand structure determination. Reactions were deliberately allowed to run “out of control” in terms of selectivity; for example the ortho-arylation of 2-phenylpyridine gave five products resulting from mono- and bisarylations combined with SNAr processes. As a result, a number of crystallographic hits against NUDT7, a key peroxisomal CoA ester hydrolase, have been identified.  相似文献   
2.
In this paper we review the results obtained in the last two years with the Orsay free electron laser.  相似文献   
3.
We report the tunability of up to 150 meV of the ground state transition of self-assembled InAs quantum dots (QDs) using Mn ion implantation and subsequent annealing. Because of the exciton localization in the quantum dots, the photoluminescence efficiency (T=12K) of the quantum dot transition remains at 80% of its original value after implantation with a Mn dose of 1×1013 cm−2ions. Strong luminescence still remains at room temperature. At a high implantation dose (1×1015 cm−2) and rapid thermal annealing (700°C for 60s) about 25% of the QD luminescence intensity is recovered at T=12K.  相似文献   
4.
The effect of an organically surface modified layered silicate on the viscosity of various epoxy resins of different structures and different functionalities was investigated. Steady and dynamic shear viscosities of the epoxy resins containing 0–10 Wt% of the organoclay were determined using parallel plate rheology. Viscosity results were compared with those achieved through addition of a commonly used micronsized CaCO3 filler. It was found that changes in viscosities due to the different fillers were of the same order, since the layered silicate was only dispersed on a micron‐sized scale in the monomer (prior to reaction), as indicated by X‐ray diffraction measurements. Flow activation energies at a low frequency were determined and did not show any significant changes due to the addition of organoclay or CaCO3. Comparison between dynamic and steady shear experiments showed good agreement for low layered silicate concentrations below 7.5 wt%, i.e. the Cox‐Merz rule can be applied. Deviations from the Cox‐Merz rule appeared at and above 10 wt%, although such deviations were only slightly above experimental error. Most resin organoclay blends were well predicted by the Power Law model, only concentrations of 10 wt% and above requiring the Herschel‐Buckley (yield stress) model to achieve better fits. Wide‐angle X‐ray measurements have shown that the epoxy resin swells the layered silicate with an increase in the interlayer distance of approximately 15 Å, and that the rheology behavior is due to the lateral, micron‐size of these swollen tactoids.  相似文献   
5.
This paper presents GPELab (Gross–Pitaevskii Equation Laboratory), an advanced easy-to-use and flexible Matlab toolbox for numerically simulating many complex physics situations related to Bose–Einstein condensation. The model equation that GPELab solves is the Gross–Pitaevskii equation. The aim of this first part is to present the physical problems and the robust and accurate numerical schemes that are implemented for computing stationary solutions, to show a few computational examples and to explain how the basic GPELab functions work. Problems that can be solved include: 1d, 2d and 3d situations, general potentials, large classes of local and nonlocal nonlinearities, multi-components problems, and fast rotating gases. The toolbox is developed in such a way that other physics applications that require the numerical solution of general Schrödinger-type equations can be considered.  相似文献   
6.
This paper introduces a system for the direct editing of highlights produced by anisotropic BRDFs, which we call anisotropic highlights. We first provide a comprehensive analysis of the link between the direction of anisotropy and the shape of highlight curves for arbitrary object surfaces. The gained insights provide the required ingredients to infer BRDF orientations from a prescribed highlight tangent field. This amounts to a non‐linear optimization problem, which is solved at interactive framerates during manipulation. Taking inspiration from sculpting software, we provide tools that give the impression of manipulating highlight curves while actually modifying their tangents. Our solver produces desired highlight shapes for a host of lighting environments and anisotropic BRDFs.  相似文献   
7.
High-performance size-exclusion chromatography (HPSEC) was used to evaluate the influence of different variables affecting the transesterification of rapeseed oil (RSO) with anhydrous ethanol and sodium ethoxide as catalyst. The effect of temperature, ethanol/RSO molar ratio, catalyst concentration, and time can be interpreted by observing the variations of the reaction medium composition. HPSEC has made the quantitation of ethyl esters, mono-, di-, and triglycerides and glycerol possible. The best results for laboratory-scale reactions were obtained at 80°C with a 6:1 molar ratio of EtOH/RSO and 1% of NaOEt by weight of RSO.  相似文献   
8.
9.
Cu(In,Ga)Se2-based solar cells have reached efficiencies close to 23%. Further knowledge-driven improvements require accurate determination of the material properties. Here, we present refractive indices for all layers in Cu(In,Ga)Se2 solar cells with high efficiency. The optical bandgap of Cu(In,Ga)Se2 does not depend on the Cu content in the explored composition range, while the absorption coefficient value is primarily determined by the Cu content. An expression for the absorption spectrum is proposed, with Ga and Cu compositions as parameters. This set of parameters allows accurate device simulations to understand remaining absorption and carrier collection losses and develop strategies to improve performances.  相似文献   
10.
The aim of this paper is to present the principles and results about case-based reasoning adapted to real-time interactive simulations, more precisely concerning retrieval mechanisms. The article begins by introducing the constraints involved in interactive multiagent-based simulations. The second section presents a framework stemming from case-based reasoning by autonomous agents. Each agent uses a case base of local situations and, from this base, it can choose an action in order to interact with other autonomous agents or users’ avatars. We illustrate this framework with an example dedicated to the study of dynamic situations in football. We then go on to address the difficulties of conducting such simulations in real-time and propose a model for case and for case base. Using generic agents and adequate case base structure associated with a dedicated recall algorithm, we improve retrieval performance under time pressure compared to classic CBR techniques. We present some results relating to the performance of this solution. The article concludes by outlining future development of our project.  相似文献   
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