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111.
Frank W. Crow Michael L. Gross Maurice M. Bursey 《Journal of mass spectrometry : JMS》1981,16(7):309-311
Collisional activation of the molecular ions of 1-propanol, 2-propanol and methyl ethyl ether, and of the m/z 60 ion from 1,2-dimethoxyethane provides evidence for four distinct forms of [C3H8O]+˙. Collision induced decompositions may be explained either by simple cleavages, by cyclic processes involving adjacent substituents, or by bicyclic processes of adjacent substituents. Evidence for a form of [C3H8O]+˙ in which charge and radical site are separate is assembled from the spectra. 相似文献
112.
Eugene P. Gross 《Journal of statistical physics》1981,25(4):585-604
We present a microscopic theory of the problem of finding the properties of a particle interacting with potentials located at random sites. The sites are governed by a general probability distribution. The starting point is the multiple scattering equations for the amplitude k
1|T
|k
2 in terms of the individual scattering amplitudes k
1|T
|k
2. We work with quantitiesA
defined by k
1|T
|k
2=k
1|T
|k
2exp[i(k
1–k
2)R
]. The theory is based on a splitting of the fundamental equation forA into equations for the mean A and the fluctuationsAA
. Neglect of the fluctuations yields the quasicrystalline approximation. We rearrange the equation forAA
to isolate the collective part of the fluctuations. We then make the simplest microscopic truncation which is thatAA
is a restricted two-body additive function of the site positions. With the contribution of the collective fluctuations, this yields results forA that are accurate to ordert
4.Work supported in part by the National Science Foundation under Contract No. NSF DMRWork supported in part by the National Science Foundation under Contract No. NSF DMR 相似文献
113.
Let R be a noetherian ring of dimension d and M a finitely generated R-module of homologic dimension less or equal to one. Assume further that M has a rank r, which equals d or (in case d>0) d?1 and that the r-th Fitting-ideal \(\vartheta _r (M)\) of M has grade ?d. Then the torsion-submodule of the d-th exterior power of M and the module \(R/\vartheta _r (M)\) are equivalent. 相似文献
114.
Fabian Gyger André Sackmann Michael Hübner Pascal Bockstaller Dagmar Gerthsen Henning Lichtenberg Jan‐Dierk Grunwaldt Nicolae Barsan Udo Weimar Claus Feldmann 《Particle & Particle Systems Characterization》2014,31(5):591-596
Pd@SnO2 and SnO2@Pd core@shell nanocomposites are prepared via a microemulsion approach. Both nanocomposites exhibit high‐surface, porous matrices of SnO2 shells (>150 m2 g?1) with very small SnO2 crystallites (<10 nm) and palladium (Pd) nanoparticles (<10 nm) that are uniformly distributed in the porous SnO2 matrix. Although similar by first sight, Pd@SnO2 and SnO2@Pd are significantly different in view of their structure with Pd inside or outside the SnO2 shell and in view of their sensor performance. As SMOX‐based sensors (SMOX: semiconducting metal oxide), both nanocomposites show a very good sensor performance for the detection of CO and H2. Especially, the Pd@SnO2 core@shell nanocomposite is unique and shows a fast response time (τ90 < 30 s) and a very good response at low temperature (<250 °C), especially under humid‐air conditions. Extraordinarily high sensor signals are observed when exposing the Pd@SnO2 nanocomposite to CO in humid air. Under these conditions, even commercial sensors (Figaro TGS 2442, Applied Sensor MLC, E2V MICS 5521) are outperformed. 相似文献
115.
116.
117.
Francis E. Burstall Udo Hertrich-Jeromin Wayne Rossman 《Comptes Rendus Mathematique》2012,350(7-8):413-416
We show how linear Weingarten surfaces appear as special Ω-surfaces and give a characterization of those linear Weingarten surfaces that allow a Weierstrass type representation. 相似文献
118.
119.
Qiu-Cheng Chen Zi-Ye Xiao Shachar Fite Dr. Amir Mizrahi Dr. Natalia Fridman Xuan Zhan Or Keisar Dr. Yair Cohen Prof. Dr. Zeev Gross 《Chemistry (Weinheim an der Bergstrasse, Germany)》2019,25(48):11383-11388
Although the affinity of metallocorroles to axial ligands is quite low, this is not the case when the chelated element is phosphorus. This work is hence focused on the mechanism of ligand exchange of six-coordinate phosphorus corroles as a tool for affecting their chemical and physical properties. These fundamental investigations allowed for the development of facile methodologies for the synthesis of a large series of complexes and the establishment of several new structure/activity profiles that may be used to understand and predict spectroscopic features and for tailor-made modification of photophysical and electrochemical properties. This is exemplified by the facile access to complexes with terminal groups that are of large potential for practical applications based on click chemistry, optical imaging, and surface science. 相似文献
120.
Nora Jannsen Dr. Stefano Diodati Nicola Dengo Francesca Tajoli Dr. Nicola Vicentini Dr. Giacomo Lucchini Prof. Adolfo Speghini Prof. Denis Badocco Prof. Paolo Pastore Prof. Silvia Gross 《Chemistry (Weinheim an der Bergstrasse, Germany)》2019,25(59):13624-13634
The aim of this work was i) to develop a hydrothermal, low-temperature synthesis protocol affording the upconverting hexagonal phase NaYF4 with suitable dopants while adhering to the “green chemistry” standards and ii) to explore the effect that different parameters have on the products. In optimizing the synthesis protocol, short reaction times and low temperatures (below 150 °C) were considered. Yb3+ and Er3+ ions were chosen as dopants for the NaYF4 material. Within the context of the second goal, parameters including nature of the precursors, treatment temperature, and treatment time were investigated to afford a pure hexagonal crystalline phase, both in the doped and undoped materials. To fully explore the synthesis results, the prepared materials were characterized from a structural (XRD), compositional (XPS, ICP-MS), and morphological (SEM) point of view. The upconverting properties of the compounds were confirmed by photoluminescence measurements. 相似文献