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1.
E. Casarejos P. Armbruster L. Audouin J. Benlliure M. Bernas A. Boudard R. Legrain S. Leray B. Mustapha S. Czajkowski T. Enqvist B. Fernandez J. Pereira M. Pravikoff F. Rejmund K. -H. Schmidt C. Stephan J. Taieb L. Tassan-Got C. Villagrasa C. Volant W. Wlazlo 《Physics of Atomic Nuclei》2003,66(8):1413-1420
The isotopic production cross sections of heavy residues in relativistic heavy-ion collisions have been investigated in inverse kinematics. The primary reaction products were fully identified in mass and atomic number prior to beta decay using the fragment separator FRS. The huge collection of data obtained helps in the understanding of the two main reaction mechanisms involved: fragmentation and fission. These data provide basic information for future radioactive ion beam facilities and for technical applications like intense neutron sources by means of spallation targets. 相似文献
2.
Jocelyne Hellou Raymond J. Andersen Shahin Rafii Edward Arnold Jon Clardy 《Tetrahedron letters》1981,22(42):4173-4176
The structure of luteone (), a twenty three carbon terpenoid, has been solved by performing a single crystal x-ray analysis on a 3,4-dinitrophenylhydrazone derivative. 相似文献
3.
Robert Kolodziuk Mustapha Tollabi Catherine Goux-Henry Denis Sinou 《Journal of organometallic chemistry》2003,687(2):384-391
Carbohydrate-substituted phosphines are easily obtained in quite good yields by coupling of protected or non-protected d-glucosamine with the corresponding diphenylphosphino acid. These neutral ligands, in association with palladium acetate, are very active catalysts in the Suzuki cross-coupling reaction. The polyhydroxy phosphines are more active than the peracetylated phosphines. The process tolerates electron-rich as well as electron-poor substituents. Excellent turnovers, up to 97?000 are observed. 相似文献
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Bazzi Aicha Abbiche Khalid Izzaouihda Safia Acharjee Nivedita Zejli Hanane Marakchi Khadija Komiha Najia El Issami Souad Bazzi Lahcen Hilali Mustapha 《Structural chemistry》2021,32(6):2183-2198
Structural Chemistry - A combined experimental and theoretical study is presented to predict and analyze the inhibition efficiency and adsorption mechanism of 4-aminobenzoic acid molecule for... 相似文献
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Gregory B. Kharas Emi Hanawa Benjamin L. Hill Salima Atlas Mustapha Raihane 《高分子科学杂志,A辑:纯化学与应用化学》2013,50(7):650-655
Copolymerization of 2-phenyl-1,1-dicyanoethylene (PDE) with 4-fluorostyrene and pentafluorostyrene in solution with radical initiation (ABCN) at 70°C yielded random copolymers with PDE alternating units. The composition of the copolymers was calculated from nitrogen analysis and the structure was analyzed by IR, 1H and 13C-NMR. The order of relative reactivity (1/r1) and the tendency toward alternation of monomer units in the copolymer for these two monomers, is 4-fluorostyrene (1.96) > pentafluorostyrene (0.51). Higher glass transition temperature of the copolymers in comparison with that of homopolymers indicates a decrease in chain mobility of the copolymer due to the high dipolar character of the trisubstituted ethylene monomer unit. 相似文献
9.
The N-arylation of indoles with a variety of aryl bromides is reported using copper oxide nanoparticles as a heterogeneous catalyst. These copper oxide nanoparticles, which were produced in a novel, facile, and scalable fashion via an electrospinning technique, resulted in an excellent product yield under mild conditions. Moreover, the catalyst was easily recovered and reused several times without significant loss of activity. 相似文献
10.
Isaiah Adelabu Patrick TomHon Mohammad S. H. Kabir Shiraz Nantogma Mustapha Abdulmojeed Iuliia Mandzhieva Dr. Jessica Ettedgui Dr. Rolf E. Swenson Dr. Murali C. Krishna Prof. Thomas Theis Prof. Boyd M. Goodson Prof. Eduard Y. Chekmenev 《Chemphyschem》2022,23(2):e202100839
Signal Amplification By Reversible Exchange in SHield Enabled Alignment Transfer (SABRE-SHEATH) is investigated to achieve rapid hyperpolarization of 13C1 spins of [1-13C]pyruvate, using parahydrogen as the source of nuclear spin order. Pyruvate exchange with an iridium polarization transfer complex can be modulated via a sensitive interplay between temperature and co-ligation of DMSO and H2O. Order-unity 13C (>50 %) polarization of catalyst-bound [1-13C]pyruvate is achieved in less than 30 s by restricting the chemical exchange of [1-13C]pyruvate at lower temperatures. On the catalyst bound pyruvate, 39 % polarization is measured using a 1.4 T NMR spectrometer, and extrapolated to >50 % at the end of build-up in situ. The highest measured polarization of a 30-mM pyruvate sample, including free and bound pyruvate is 13 % when using 20 mM DMSO and 0.5 M water in CD3OD. Efficient 13C polarization is also enabled by favorable relaxation dynamics in sub-microtesla magnetic fields, as indicated by fast polarization buildup rates compared to the T1 spin-relaxation rates (e. g., ∼0.2 s−1 versus ∼0.1 s−1, respectively, for a 6 mM catalyst-[1-13C]pyruvate sample). Finally, the catalyst-bound hyperpolarized [1-13C]pyruvate can be released rapidly by cycling the temperature and/or by optimizing the amount of water, paving the way to future biomedical applications of hyperpolarized [1-13C]pyruvate produced via comparatively fast and simple SABRE-SHEATH-based approaches. 相似文献