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681.
Mark R. Crimmin Neil C. Tomson Robert G. Bergman F. Dean Toste 《Journal of organometallic chemistry》2011,696(25):3974-3981
[(TMEDA)Co(NO)2][BPh4] reacts with Group 1 salts of various monoanionic ligands to yield four and five coordinate {Co(NO)2}10 complexes. The synthesis of the four coordinate complex of the form [{LX}Co(NO)2] via salt-metathesis reactions of [(TMEDA)Co(NO)2][BPh4] with [{ArNC(Me)CHC(Me)NAr}Li(OEt2)] (Ar = 2,6-di-iso-propylphenyl) is reported. In addition [(TMEDA)Co(NO)2][BPh4] reacts with either KTp∗ or a suite of cyclopentadienyllithium and cyclopentadienylsodium reagents, to generate the corresponding five coordinate [{L2X}Co(NO)2] complexes ({L2X = C5H5, MeC5H4, Cp∗, tBuC5H4, Ph2CHC5H4, Me3SiC5H4, tBuMe2SiC5H4, iPr3SiC5H4, 1,3-(iPr3Si)2C5H3 and Tp∗). In support of existing precedent, the four coordinate complex is a thermally robust and readily isolable species while five coordinate complexes are thermally unstable transient intermediates that may either undergo dissociation of an NO ligand or be trapped by alkenes to form the corresponding metal dinitrosoalkane complexes. These reactions demonstrate that [(TMEDA)Co(NO)2][BPh4] provides a versatile synthetic entry point to cobalt dinitrosyl complexes and obviates the need for the repeated use of nitric oxide in the preparation of dinitrosoalkane complexes of cobalt. 相似文献
682.
Y. Fleger M. Rosenbluh Y. M. Strelniker D. J. Bergman A. N. Lagarkov 《The European Physical Journal B - Condensed Matter and Complex Systems》2011,81(1):85-93
The extinction spectrum of a
dielectric film with periodic array of metallic
islands of different shapes and different
mutual distances
was studied both theoretically
and experimentally. It is shown, analytically,
numerically and experimentally, that the
positions of the surface plasmon resonances depend on
the nano-structural details.
We propose two ways of controlling plasmon resonance frequency:
changing the aspect ratio
of the elliptical (or rectangular) islands and changing their
mutual distances.
A new analytical asymptotic approach for calculating the optical
properties of such plasmonic systems is developed.
The results of our analytical and numerical studies are in
good qualitative agreement with experiment. 相似文献
683.
A. A. Alekseev A. A. Bergman A. I. Berlev E. A. Koptelov B. F. Samylin M. I. Svirin A. M. Trufanov B. I. Fursov V. S. Shorin 《Physics of Atomic Nuclei》2010,73(9):1487-1498
The cross section for 244Cm fission induced by neutrons of energy in the range between 0.07 eV and 20 keV was measured by using the lead slowing-down
spectrometer (LSDS-100) of the Institute for Nuclear Research (Russian Academy of Sciences, Moscow). The parameters of the
resonance areas were determined for the lowest eight s-wave neutron resonances, and the respective fission widths were evaluated. Also, the parameters of the intermediate structure
in the cross section for the subbarrier fission of 244Cm nuclei were evaluated. The results were compared with available data and recommendations based on evaluations. 相似文献
684.
A. A. Alekseev A. A. Bergman A. I. Berlev E. A. Koptelov B. F. Samylin A. M. Trufanov B. I. Fursov V. S. Shorin 《Physics of Atomic Nuclei》2010,73(10):1645-1655
The cross section for 246Cm fission induced by neutrons of energy in the range 0.1 eV-20 keV was measured by the neutron lead slowing-down spectrometer
(LSDS-100) of the Institute for Nuclear Research (INR, Russian Academy of Sciences, Moscow). The parameters of the resonance
area and of the fission width were evaluated for several low-lying s-wave neutron resonances. The parameters of the intermediate structure in the cross section for the subbarrier fusion of 246Cm nuclei were found. The results obtained in this way were compared with available experimental data and with recommended
evaluated data. 相似文献
685.
Harrison M. Bergman D. Dawson Beattie Gavin R. Kiel Rex C. Handford Yi Liu T. Don Tilley 《Chemical science》2022,13(19):5568
The synthesis of polycyclic aromatic hydrocarbons (PAHs) and related nanographenes requires the selective and efficient fusion of multiple aromatic rings. For this purpose, the Diels–Alder cycloaddition has proven especially useful; however, this approach currently faces significant limitations, including the lack of versatile strategies to access annulated dienes, the instability of the most commonly used dienes, and difficulties with aromatization of the [4 + 2] adduct. In this report we address these limitations via the marriage of two powerful cycloaddition strategies. First, a formal Cp2Zr-mediated [2 + 2 + 1] cycloaddition is used to generate a stannole-annulated PAH. Secondly, the stannoles are employed as diene components in a [4 + 2] cycloaddition/aromatization cascade with an aryne, enabling π-extension to afford a larger PAH. This discovery of stannoles as highly reactive – yet stable for handling – diene equivalents, and the development of a modular strategy for their synthesis, should significantly extend the structural scope of PAHs accessible by a [4 + 2] cycloaddition approach.Stannoles are introduced as a new, spontaneously aromatizing diene for [4 + 2] cycloadditions that can be easily introduced into diverse conjugated systems, facilitating the efficient synthesis of complex PAHs and their π-extension. 相似文献
686.
Amey Nimkar Gil Bergman Elad Ballas Nophar Tubul Noam Levi Fyodor Malchik Idan Kukurayeve Munseok S. Chae Daniel Sharon Mikhael Levi Netanel Shpigel Guoxiu Wang Doron Aurbach 《Angewandte Chemie (International ed. in English)》2023,62(50):e202306904
The exploration of cathode and anode materials that enable reversible storage of mono and multivalent cations has driven extensive research on organic compounds. In this regard, polyimide (PI)-based electrodes have emerged as a promising avenue for the development of post-lithium energy storage systems. This review article provides a comprehensive summary of the syntheses, characterizations, and applications of PI compounds as electrode materials capable of hosting a wide range of cations. Furthermore, the review also delves into the advancements in PI based solid state batteries, PI-based separators, current collectors, and their effectiveness as polymeric binders. By highlighting the key findings in these areas, this review aims at contributing to the understanding and advancement of PI-based structures paving the way for the next generation of energy storage systems. 相似文献
687.
688.