排序方式: 共有27条查询结果,搜索用时 15 毫秒
21.
David Harris Gael M. Martin Indeewara Perera D. S. Poskitt 《Journal of computational and graphical statistics》2019,28(1):92-104
The focus of this article is on the quantification of sampling variation in frequentist probabilistic forecasts. We propose a method of constructing confidence sets that respects the functional nature of the forecast distribution, and use animated graphics to visualize the impact of parameter uncertainty on the location, dispersion, and shape of the distribution. The confidence sets are derived via the inversion of a Wald test, and the ellipsoid that defines the boundary of the set computed numerically. A wide range of linear and nonlinear time series models—encompassing long memory, state space, and mixture specifications—is used to demonstrate the procedure, based on artificially generated data. An empirical example in which distributional forecasts of both financial returns and its stochastic volatility are produced is then used to illustrate the practical importance of accommodating sampling variation in the manner proposed. 相似文献
22.
Florian Maire Gael Coadou Laetitia Cravello Catherine M. Lange 《Journal of the American Society for Mass Spectrometry》2013,24(2):238-248
We reported the use of ion mobility (IM) combined with mass spectrometry (MS) as an analytical tool to investigate low generation polyamidoanine (PAMAM) dendrimers. This analytical approach has been employed to separate ions of defective structures with different charge state but exactly the same m/z value. Tandem mass spectrometry (MS/MS) after IM separation allowed a comprehensive structural characterization of defective dendrimers. In addition, IM was used to evaluate the collision cross-sections of ions of perfect dendrimers. They showed a good correlation with calculated collision cross-sections obtained by the trajectory method (TM) and were also consistent with dimensions reported by other established analytical methods. 相似文献
23.
TiO2‐mediated photocatalysis is widely used in a variety of applications and products in the envi‐ronmental and energy fields, including photoelectrochemical conversion, self‐cleaning surfaces, and especially water purification systems. The dimensionality of the structure of a TiO2 material can affect its properties, functions, and more specifically, its photocatalytic performance. In this work, the photocatalytic inactivation of Gram‐negative Escherichia coli using three photocatalysts, differ‐ing in their structure and other characteristics, was studied in a batch reactor under UVA light. The aim was to establish the disinfection efficiency of solid TiO2 compared with that of suspended cata‐lysts, widely considered as reference cases for photocatalytic water disinfection. The bacterial inac‐tivation profiles obtained showed that: (1) the photoinactivation was exclusively related to the quantity of photons retained per unit of treated volume, irrespective of the characteristics of the photocatalyst and the emitted light flux densities;(2) across the whole UV light range studied, each of the photocatalytic solids was able to achieve more than 2 log bacterial inactivation with less than 2 h UV irradiation;(3) none of the used catalysts achieved a total bacterial disinfection during the treatment time. For each of the catalysts the quantum yield has been assessed in terms of disinfec‐tion efficiency, the 2D material showed almost the same performance as those of suspended cata‐lysts. This catalyst is promising for supported photocatalysis applications. 相似文献
24.
Gyuzel Yu. Mitronova Dr. Vladimir N. Belov Dr. Mariano L. Bossi Dr. Christian A. Wurm Dr. Lars Meyer Dr. Rebecca Medda Dr. Gael Moneron Dr. Stefan Bretschneider Dr. Christian Eggeling Dr. Stefan Jakobs Dr. Stefan W. Hell Prof. Dr. 《Chemistry (Weinheim an der Bergstrasse, Germany)》2010,16(15):4407-4407
25.
We present a polarization-sensitive full-field optical coherence tomography system that can produce high-resolution images of the linear retardance and reflectivity properties of biological media. En face images can be delivered at a frame rate of 3.5 Hz by combination of interferometric images acquired by two CCD cameras in an interference microscope illuminated with a tungsten halogen lamp. Isotropic spatial resolution of approximately 1.0 microm is achieved. The technique is demonstrated on ex vivo muscle tissues. 相似文献
26.
Aspinall HC Bickley JF Gaskell JM Jones AC Labat G Chalker PR Williams PA 《Inorganic chemistry》2007,46(15):5852-5860
Complexes of the early lanthanides with the donor-functionalized alkoxide ligand mmp (Hmmp = HOCMe(2)CH(2)OMe, 1-methoxy-2-methylpropan-2-ol) are excellent precursors for Metal Organic Chemical Vapor Deposition (MOCVD) and Atomic Layer Deposition (ALD) of lanthanide oxides; however, their coordination chemistry, which is the subject of this paper, is rather complex. Precursors for MOCVD and ALD of lanthanide oxides are prepared by the reaction of [Ln{N(SiMe(3))(2)}(3)] with 3 equiv of the alcohol Hmmp in toluene in the presence of 1 equiv of tetraglyme and are indefinitely stable in solution. Reaction of [Ln{N(SiMe(3))(2)}(3)] with 3 equiv of Hmmp in the absence of stabilizing Lewis bases gives complex condensed products with empirical formula [{Ln(mmp)(3-n)}(2)O(n)]. These condensed products show poor volatility and are unsatisfactory precursors for MOCVD or ALD of oxides. The cluster complex [La(3)(mu(3),kappa(2)-mmp)(2)(mu(2),kappa(2)-mmp)(3)(mmp)(4)] has been prepared by careful reaction of [La{N(SiMe(3))(2)}(3)] with 4 equiv of Hmmp and has been characterized by single-crystal X-ray diffraction. Salt metathesis reactions using M(mmp) (M = Li or Na) are unreliable routes to [Ln(mmp)(3)]. Crystals of the heterometallic cluster complex [NaLa(3)(mu(3)-OH)(mu(3),kappa(2)-mmp)(2)(mu(2),kappa(2)-mmp)(4)(mmp)(3)] were isolated from the reaction of [La(NO(3))(3)(tetraglyme)] with 3 equiv of Na(mmp), and crystals of [Li(kappa(2)-Hmmp)Pr(mu(2),eta(2)-mmp)(4))LiCl] were isolated from the reaction of PrCl(3) with 3 equiv of Li(mmp); both of these complexes have been characterized by single-crystal X-ray diffraction. 相似文献
27.
Michael Quentin Gael Pentang Lars Schimmöller Olga Kott Anja Müller-Lutz Dirk Blondin Christian Arsov Andreas Hiester Robert Rabenalt Hans-Jörg Wittsack 《Magnetic resonance imaging》2014