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31.
Nuñez AJ Shear LN Dahal N Ibarra IA Yoon J Hwang YK Chang JS Humphrey SM 《Chemical communications (Cambridge, England)》2011,47(43):11855-11857
PCM-10 is a porous phosphine coordination material based on Ca(II) and tris(p-carboxylated) triphenylphosphine. The material provides a unique 3-dimensional surface of P(III) Lewis base sites, which is ideal for post-synthetic functionalization. The addition of Au(I) yields an advanced material that can selectively adsorb 1-hexene over n-hexane at room temperature. 相似文献
32.
Nu Xu I. G. Bearden H. Bøggild J. Boissevain J. Dodd B. Erazmus S. Esumi C. W. Fabjan D. Ferenc D. E. Fields A. Franz J. Gaardhøje O. Hansen D. Hardtke H. van Hecke E. B. Holzer T. Humanic P. Hummel B. V. Jacak R. Jayanti M. Kaneta M. Kopytine M. Leltchouk T. Ljubicic B. Lörstad N. Maeda A. Medvedev M. Murray S. Nishimura H. Ohnishi G. Paic S. U. Pandey F. Piuz J. Pluta V. Polychronakos M. Potekhin G. Poulard A. Sakaguchi J. Simon-Gillo J. Schmidt-Sørensen W. Sondheim M. Spegel T. Sugitate J. P. Sullivan Y. Sumi W. J. Willis K. Wolf N. Xu D. S. Zachary 《Acta Physica Hungarica A》1996,4(1-4):263-270
We present recent results on single particle transverse momentum distributions of pions, kaons and protons, measured in CERN Experiment NA44, of 200 AGeV/c S+S and 158 AGeV/c Pb+Pb central collisions. By comparing these data with thermal and transport models, freeze-out parameters like the temperatureT fo and the chemical potentials (μ q ,μ s ) are extracted and discussed. 相似文献
33.
2-Hydroxy-3-phenyl-6-methylpyrazine is identified as the product obtained by acidic degradation of cephalexin in the presence of formaldehyde. In 5M hydrochloric acid this product gives a well-defined reduction wave with a half-wave potential of -0.45 V vs. SCE. The wave is irreversible and diffusion-controlled. The diffusion current shows a linear relation with the cephalexin concentration and can be used for determination of cephalexin in plasma. 相似文献
34.
Díez D Nuñez MG Moro RF Garrido NM Marcos IS Basabe P Urones JG 《Molecules (Basel, Switzerland)》2006,11(12):959-967
The rearrangement under oxidative conditions of 3-(benzyloxy)-tetrahydro- 2,6,6-trimethyl-2H-pyran-2-carbaldehydes to afford a chiral protected tetrahydrofuran lactol is described. 相似文献
35.
Using calculations from first principles and the concept of layer polarization, we have elucidated the nanoscale organization and local polarization in ferroelectric thin films between metallic contacts. The profile of the local polarization for different film thicknesses unveils a peculiar spatial pattern of atomic layers with uncompensated dipoles in what was originally thought to be a ferroelectric domain. This effectively ferrielectric behavior is induced by the dominant roles of the interfaces at such reduced dimensionality and can be interpreted using a simple classical model where the latter are explicitly taken into account. 相似文献
36.
The ART model is applied to study the deformed UU collision at HIRFL-CSR energy area corresponding to the high baryon density region in the QCD phase diagram. The time evolution of central baryon (energy) densities in central collisions at Eb =0.52GeV/u shows that different orientation collisions will lead to different lifetimes of high density, especially tip--tip UU collisions which have an extend lifetime for the high density phase by almost a factor of 2 compared to the body--body orientation collisions. In order to pick out the interesting tip--tip like events from a mass of random orientation collisions, we study the relation between stopping power R and impact parameter b in different orientation collisions and find that it can enhance the purity of tip--tip like events when R increases. Therefore, the high density and long lifetime events can be effectively distinguished by R selection. 相似文献
37.
Felix Nußbaumer Raphael Plangger Manuel Roeck Christoph Kreutz 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2020,132(39):17210-17217
We present the access to [5-19F, 5-13C]-uridine and -cytidine phosphoramidites for the production of site-specifically modified RNAs up to 65 nucleotides (nts). The amidites were used to introduce [5-19F, 5-13C]-pyrimidine labels into five RNAs—the 30 nt human immunodeficiency virus trans activation response (HIV TAR) 2 RNA, the 61 nt human hepatitis B virus ϵ (hHBV ϵ) RNA, the 49 nt SAM VI riboswitch aptamer domain from B. angulatum, the 29 nt apical stem loop of the pre-microRNA (miRNA) 21 and the 59 nt full length pre-miRNA 21. The main stimulus to introduce the aromatic 19F–13C-spin topology into RNA comes from a work of Boeszoermenyi et al., in which the dipole-dipole interaction and the chemical shift anisotropy relaxation mechanisms cancel each other leading to advantageous TROSY properties shown for aromatic protein sidechains. This aromatic 13C–19F labeling scheme is now transferred to RNA. We provide a protocol for the resonance assignment by solid phase synthesis based on diluted [5-19F, 5-13C]/[5-19F] pyrimidine labeling. For the 61 nt hHBV ϵ we find a beneficial 19F–13C TROSY enhancement, which should be even more pronounced in larger RNAs and will facilitate the NMR studies of larger RNAs. The [19F, 13C]-labeling of the SAM VI aptamer domain and the pre-miRNA 21 further opens the possibility to use the biorthogonal stable isotope reporter nuclei in in vivo NMR to observe ligand binding and microRNA processing in a biological relevant setting. 相似文献
38.
Brandaleze Elena Bazán Vanesa Orozco Ivana Valentini Marcelo Gomez Giuliana 《Journal of Thermal Analysis and Calorimetry》2018,133(1):435-441
Journal of Thermal Analysis and Calorimetry - Rhenium production from copper and molybdenum sulphides involves the use of a pyrometallurgical process. In traditional pyrometallurgy processes, gases... 相似文献
39.
D. A. H. Ament J. J. Nuño-Ballesteros B. Oréfice-Okamoto J. N. Tomazella 《Bulletin of the Brazilian Mathematical Society》2016,47(3):955-970
Given an analytic function germ f: (X, 0) → C on an isolated determinantal singularity or on a reduced curve, we present formulas relating the local Euler obstruction of f to the vanishing Euler characteristic of the fiber X ∩ f-1(0) and to the Milnor number of f. Restricting ourselves to the case where X is a complete intersection, we obtain an easy way to calculate the local Euler obstruction of f as the difference between the dimension of two algebras. 相似文献