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排序方式: 共有228条查询结果,搜索用时 234 毫秒
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Hao-Jung Chang Mykhailo V. Bondar Dr. Natalia Munera Dr. Sylvain David Dr. Olivier Maury Dr. Gerard Berginc Dr. Boris Le Guennic Dr. Denis Jacquemin Dr. Chantal Andraud Dr. David J. Hagan Dr. Eric W. Van Stryland 《Chemistry (Weinheim an der Bergstrasse, Germany)》2022,28(17):e202104072
The fast relaxation processes in the excited electronic states of functionalized aza-boron-dipyrromethene (aza-BODIPY) derivatives ( 1 – 4 ) were investigated in liquid media at room temperature, including the linear photophysical, photochemical, and nonlinear optical (NLO) properties. Optical gain was revealed for nonfluorescent derivatives 3 and 4 in the near infrared (NIR) spectral range under femtosecond excitation. The values of two-photon absorption (2PA) and excited-state absorption (ESA) cross-sections were obtained for 1–4 in dichloromethane using femtosecond Z-scans, and the role of bromine substituents in the molecular structures of 2 and 4 is discussed. The nature of the excited states involved in electronic transitions of these dyes was investigated using quantum-chemical TD-DFT calculations, and the obtained spectral parameters are in reasonable agreement with the experimental data. Significant 2PA (maxima cross-sections ∼2000 GM), and large ESA cross-sections ∼10−20 m2 of these new aza-BODIPY derivatives 1–4 along with their measured high photostability reveal their potential for photonic applications in general and optical limiting in particular. 相似文献
64.
Interpolation Methods for Curve Construction 总被引:1,自引:0,他引:1
Patrick S. Hagan 《Applied Mathematical Finance》2013,20(2):89-129
This paper surveys a wide selection of the interpolation algorithms that are in use in financial markets for construction of curves such as forward curves, basis curves, and most importantly, yield curves. In the case of yield curves the issue of bootstrapping is reviewed and how the interpolation algorithm should be intimately connected to the bootstrap itself is discussed. The criterion for inclusion in this survey is that the method has been implemented by a software vendor (or indeed an inhouse developer) as a viable option for yield curve interpolation. As will be seen, many of these methods suffer from problems: they posit unreasonable expections, or are not even necessarily arbitrage free. Moreover, many methods lead one to derive hedging strategies that are not intuitively reasonable. In the last sections, two new interpolation methods (the monotone convex method and the minimal method) are introduced, which it is believed overcome many of the problems highlighted with the other methods discussed in the earlier sections. 相似文献
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Hwang WL Holden MA White S Bayley H 《Journal of the American Chemical Society》2007,129(38):11854-11864
Aqueous droplets submerged in an oil-lipid mixture become enclosed by a lipid monolayer. The droplets can be connected to form robust networks of droplet interface bilayers (DIBs) with functions such as a biobattery and a light sensor. Such DIB networks might be used as model systems for the study of membrane-based biological phenomena. In this study, we develop and experimentally validate an electrical modeling approach for DIB networks by applying it to describe the current flow through a simple network containing protein pores and blocking molecules. We demonstrate the use of SPICE (Simulation Program with Integrated Circuit Emphasis) for simulating the electrical behavior of DIB networks. The modular and scalable nature of DIB networks should enable a straightforward extension of the analysis presented in this paper to large, complex networks. 相似文献
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(Poly)phenols (PPs) may have a therapeutic benefit in gastrointestinal (GI) disorders, such as irritable bowel syndrome (IBS) or inflammatory bowel disease (IBD). The aim of this review is to summarise the evidence-base in this regard. Observational evidence does not give a clear indication that PP intake has a preventative role for IBD or IBS, while interventional studies suggest these compounds may confer symptomatic and health-related quality of life improvements in known patients. There are inconsistent results for effects on markers of inflammation, but there are promising reports of endoscopic improvement. Work on the effects of PPs on intestinal permeability and oxidative stress is limited and therefore conclusions cannot be formed. Future work on the use of PPs in IBD and IBS will strengthen the understanding of clinical and mechanistic effects. 相似文献
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Examination of several accounts regarding the nature of moral responsibility allows the extraction of a conceptual core common
to all of them. Relying on that core conception of moral responsibility, the paper explores what human life without moral
responsibility would be like. That exploration establishes that many robust forms of human relationship and nonmoral normativity
could continue, absent moral responsibility, even if moral responsibility were abandoned on incompatibilist grounds. Much
more importantly, it also establishes, contra Waller and Pereboom, that only some forms of morality—so-called “behavioral”
forms—remain possible without moral responsibility. The paper argues that normative moral approaches that take into account
agent intentions in order to assess the moral status of action cannot be applied without moral responsibility of agents. Thus,
morality without responsibility needs to be behavioral, not consequentialist, as has often been thought. 相似文献
70.
Cho JY Barlow S Marder SR Fu J Padilha LA Van Stryland EW Hagan DJ Bishop M 《Optics letters》2007,32(6):671-673
The two-photon absorption spectrum of a nickel bis(dithiolene) complex with extended conjugation and pi-donor substitution is measured by using Z-scan and pump-probe techniques with femtosecond pulses over the spectral range from 1.20 to 1.58 microm, which includes much of the telecommunications range. The peak two-photon cross section of over 5000 GM (1 GM = 10(-50) cm4 s photon(-1) molecule(-1)) occurs at approximately 1.24 microm, with significant two-photon absorption (>440 GM) throughout the spectral range examined. 相似文献