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81.
In this note we show by means of a simple example that, if the maximin problem with (nonlinear) concave increasing utility
functions is solved by inspecting the extreme points of the (generalized) Voronoi diagram (as usually proposed), one may have
to inspect an infinite number of candidate points.
The research of the second and third authors is partially supported by Grant PB96-1416-C02-02 of Ministerio de Educación y
Cultura, Spain 相似文献
82.
This paper focuses on the deposition of silicon oxide thin films, using laser assisted CVD based on a CO2 laser, and on the feasibility of the process for coating porous silicon samples. Scanning electron and atomic force microscopy were used to analyse the morphology and microstructure of the films, while structure and chemical composition were determined by Fourier transform infrared and Rutherford backscattering spectroscopy. Two-wavelength ellipsometry was used for thickness and refractive index evaluation. The photoluminescence of SiO2/PS was measured and compared with that of uncoated samples. 相似文献
83.
84.
85.
J. Luis Casarrubio Santiago Conde Carlos Corral Jaime Lissavetzky 《Journal of heterocyclic chemistry》1983,20(6):1557-1560
The synthesis of the thiophene analogs of the cardio-selective β-adrenergic blocking agents Practolol and “reversed” Practolol has been attempted starting from 2-acetyl-5-bromothiophene. Although this synthesis worked for the second compound it was not possible to obtain the first one. From this and other results of this paper it can be deduced that the thiophene analog of Practolol must be an unstable compound. 相似文献
86.
87.
Dr. Damian E. Yerien Dr. Jessica Groppi Prof. Al Postigo Prof. Alberto Credi Romina S. Conde Prof. Massimo Baroncini Dr. Sebastian Barata-Vallejo 《European journal of organic chemistry》2023,26(27):e202300478
Modified crown ethers are fundamental building blocks in supramolecular chemistry, with applications in phase transfer catalysis, metal extraction, smart materials, and molecular machines. Here we report on a one-pot highly chemo- and regioselective photocatalytic fluoroalkylation protocol for the mono-functionalization of benzo substituted crown ethers. For this important class of macrocycles, the method described here represents one of the few late-stage functionalization procedures that is both high yielding and scalable. Because of its breadth of scope and substrate tolerance, the devised approach can be applied to a wide range of aromatic crown ethers (18 examples, up to 99 % yield), including those engaged in mechanically interlocked molecules. 相似文献
88.
Jesús Conde–Lago 《代数通讯》2017,45(2):774-775
Proofs that a smooth morphism is flat available in the literature are long and di?cult. We give a short proof of this fact. 相似文献
89.
Jing C Kanareykin A Power JG Conde M Yusof Z Schoessow P Gai W 《Physical review letters》2007,98(14):144801
One approach to future high energy particle accelerators is based on the wakefield principle: a leading high-charge drive bunch is used to excite fields in an accelerating structure or plasma that in turn accelerates a trailing low-charge witness bunch. The transformer ratio R is defined as the ratio of the maximum energy gain of the witness bunch to the maximum energy loss of the drive bunch. In general, R<2 for this configuration. A number of techniques have been proposed to overcome the transformer ratio limitation. We report here the first experimental study of the ramped bunch train (RBT) technique in a dielectric based accelerating structure. A single drive bunch was replaced by two bunches with charge ratio of 1:2.5 and a separation of 10.5 wavelengths of the fundamental mode. An average measured transformer ratio enhancement by a factor of 1.31 over the single drive bunch case was obtained. 相似文献
90.
Dr. He Li Dr. João Conde Ana Guerreiro Dr. Gonçalo J. L. Bernardes 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2020,132(37):16157-16166
The bioorthogonal inverse-electron-demand Diels–Alder (IEDDA) cleavage reaction between tetrazine and trans-cyclooctene (TCO) is a powerful way to control the release of bioactive agents and imaging probes. In this study, a pretargeted activation strategy using single-walled carbon nanotubes (SWCNTs) that bear tetrazines (TZ@SWCNTs) and a TCO-caged molecule was used to deliver active effector molecules. To optimize a turn-on signal by using in vivo fluorescence imaging, we developed a new fluorogenic near-infrared probe that can be activated by bioorthogonal chemistry and image tumours in mice by caging hemicyanine with TCO (tHCA). With our pretargeting strategy, we have shown selective doxorubicin prodrug activation and instantaneous fluorescence imaging in living cells. By combining a tHCA probe and a pretargeted bioorthogonal approach, real-time, non-invasive tumour visualization with a high target-to-background ratio was achieved in a xenograft mice tumour model. The combined advantages of enhanced stability, kinetics and biocompatibility, and the superior pharmacokinetics of tetrazine-functionalised SWCNTs could allow application of targeted bioorthogonal decaging approaches with minimal off-site activation of fluorophore/drug. 相似文献