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931.
Ho Ngoc Phien 《Physics letters. A》2008,372(16):2825-2829
We propose a linear optics scheme to teleport an arbitrary two-mode coherent state. The devices used are beam-splitters, phase-shifters and ideal photo-detectors capable of distinguishing between even and odd photon numbers. The scheme achieves faithful teleportation with a probability of 1/4. However, with additional use of an appropriate displacement operator, the teleported state can always be made near-faithful. 相似文献
932.
Kneip S Nagel SR Bellei C Bourgeois N Dangor AE Gopal A Heathcote R Mangles SP Marquès JR Maksimchuk A Nilson PM Phuoc KT Reed S Tzoufras M Tsung FS Willingale L Mori WB Rousse A Krushelnick K Najmudin Z 《Physical review letters》2008,100(10):105006
The dynamics of plasma electrons in the focus of a petawatt laser beam are studied via measurements of their x-ray synchrotron radiation. With increasing laser intensity, a forward directed beam of x rays extending to 50 keV is observed. The measured x rays are well described in the synchrotron asymptotic limit of electrons oscillating in a plasma channel. The critical energy of the measured synchrotron spectrum is found to scale as the Maxwellian temperature of the simultaneously measured electron spectra. At low laser intensity transverse oscillations are negligible as the electrons are predominantly accelerated axially by the laser generated wakefield. At high laser intensity, electrons are directly accelerated by the laser and enter a highly radiative regime with up to 5% of their energy converted into x rays. 相似文献
933.
Christelle N’Ta Ambeu Rémy Le Guével Anne Corlu Janat Akhanovna Mamyrbekova Jean-Pierre Bazureau 《Molecular diversity》2018,22(3):685-708
A series of 16 new ethyl \(\upbeta \)-amino benzimidazole acrylate derivatives 12(a–p) with a (2E)-s-cis/trans conformation and bearing two points of diversity was designed and synthesized by using a multi-step strategy (reductive amination, deprotection in acidic media and transamination) in moderate to good yields from ethyl 3-dimethylamino-2-(1H-benzimidazol-2-yl)acrylate (5) and monosubstituted N-Boc diamines (7a,7b) as starting building blocks. Products 12 were evaluated for their in vitro cytotoxic potential against six selected human cell lines (Huh7-D12, Caco2, MDA-MB231, HCT116, PC3 and NCI-H727). Compounds 12a, 12e and 12l exhibited selective and micromolar antitumor activities against Huh7-D12 and Caco2 cell lines. 相似文献
934.
Transient terminal phosphinidene complexes [RP-M(CO)5] (M = Mo, W, R = Ph, Me), as generated from the corresponding 7-phosphanorbornadiene complexes, react with N-methyl(benzylidene)amine to afford the diazaphospholane complexes 3,4 (R = Ph) or a mixture of diazaphospholane 9 and 1,2,3-azadiphosphetidine 10 (R = Me), probably by insertion of either one molecule of imine or one molecule of phosphinidene into the weak P N bond of the unstable intermediate azaphosphiridine 11. The new complex 10 has been submitted to an X-ray crystal structure analysis. © 1998 John Wiley & Sons, Inc. Heteroatom Chem 9: 597–600, 1998 相似文献
935.
Kyoung Chul Park Prof. Dr. Preecha Kittikhunnatham Dr. Jaewoong Lim Grace C. Thaggard Yuan Liu Dr. Corey R. Martin Dr. Gabrielle A. Leith Donald J. Toler Dr. An T. Ta Dr. Nancy Birkner Dr. Ingrid Lehman-Andino Dr. Alejandra Hernandez-Jimenez Dr. Gregory Morrison Dr. Jake W. Amoroso Prof. Dr. Hans-Conrad zur Loye Dr. Dave P. DiPrete Dr. Mark D. Smith Prof. Dr. Kyle S. Brinkman Prof. Dr. Simon R. Phillpot Prof. Dr. Natalia B. Shustova 《Angewandte Chemie (International ed. in English)》2023,62(5):e202216349
A novel series of heterometallic f-block-frameworks including the first examples of transuranic heterometallic 238U/239Pu-metal–organic frameworks (MOFs) and a novel monometallic 239Pu-analog are reported. In combination with theoretical calculations, we probed the kinetics and thermodynamics of heterometallic actinide(An)-MOF formation and reported the first value of a U-to-Th transmetallation rate. We concluded that formation of uranyl species could be a driving force for solid-state metathesis. Density of states near the Fermi edge, enthalpy of formation, band gap, proton affinity, and thermal/chemical stability were probed as a function of metal ratios. Furthermore, we achieved 97 % of the theoretical maximum capacity for An-integration. These studies shed light on fundamental aspects of actinide chemistry and also foreshadow avenues for the development of emerging classes of An-containing materials, including radioisotope thermoelectric generators or metalloradiopharmaceuticals. 相似文献
936.
Dr. Amit Kumar Simlandy Turki M. Alturaifi Dr. Johny M. Nguyen Dr. Lucas J. Oxtoby Quynh Nguyen Wong Dr. Jason S. Chen Prof. Peng Liu Prof. Keary M. Engle 《Angewandte Chemie (International ed. in English)》2023,62(29):e202304013
The catalytic enantioselective synthesis of α-chiral alkenes and alkynes represents a powerful strategy for rapid generation of molecular complexity. Herein, we report a transient directing group (TDG) strategy to facilitate site-selective palladium-catalyzed reductive Heck-type hydroalkenylation and hydroalkynylation of alkenylaldehyes using alkenyl and alkynyl bromides, respectively, allowing for construction of a stereocenter at the δ-position with respect to the aldehyde. Computational studies reveal the dual beneficial roles of rigid TDGs, such as L-tert-leucine, in promoting TDG binding and inducing high levels of enantioselectivity in alkene insertion with a variety of migrating groups. 相似文献
937.
Taşkesen Bahar Shafieezadeh-Abadeh Soroosh Kuhn Daniel 《Mathematical Programming》2023,199(1-2):1033-1106
Mathematical Programming - Semi-discrete optimal transport problems, which evaluate the Wasserstein distance between a discrete and a generic (possibly non-discrete) probability measure, are... 相似文献
938.
Y. Guhel M. T. Ta J. Bernard B. Boudart J. C. Pesant 《Journal of Raman spectroscopy : JRS》2009,40(4):401-404
We investigated by Raman spectroscopy (RS) the crystalline quality of CeO2 thin films radio frequency magnetron sputtered on n‐type (111) Si substrates from CeO2 target. The deposition temperature was in the range of 200–800 °C. We also realized structural investigations on CeO2 layers after Rapid Thermal Annealing (RTA) performed in the range of 750–1000 °C for 30 s under nitrogen atmosphere. So this study displays that a high‐growth temperature and a high post‐growth‐RTA temperature improves the crystalline structure of the film. In fact, the best crystalline quality, which is close to the CeO2 target taken as a reference, is obtained for a CeO2 layer deposited at 800 °C and post‐annealed at 1000 °C for 30 s. Copyright © 2008 John Wiley & Sons, Ltd. 相似文献
939.
940.
Malonate anion traps the [RP-W(CO)5] bridge of 7-phosphanorbornadiene complexes 1–3 to give functional secondary phosphine complexes [RP(H)-CH(CO2Et)2]W(CO)5 ( 7–9 ). Metalation of these complexes by NaH in THF occurs at the malonic CH group, but the alkylation of the resulting carbanions preferentially takes place at phosphorus. When R stands for β-chloroethyl, the corresponding carbanion cyclizes to give the functional phosphirane complex 11 . © 2004 Wiley Periodicals, Inc. Heteroatom Chem 15:258–262, 2004; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/hc.20014 相似文献