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91.
92.
X. Jiang G.A. Navarro R. Sassot 《The European Physical Journal C - Particles and Fields》2006,47(1):81-85
We investigate the potential impact of forthcoming Jefferson Lab semi-inclusive polarized deep inelastic scattering proton
measurements in the determination of the sea quark polarization in the nucleons by means of a next to leading order global
QCD analysis. Specifically, we estimate the resulting improvement in the constraints on polarized parton densities for different
flavors, which is found to be significant for up and strange quarks, and the correlation between remaining uncertainty ranges
for each of the parton species.
PACS 12.38.Bx, 13.85.Ni 相似文献
93.
Gabriel Navarro 《Israel Journal of Mathematics》2002,132(1):277-283
Suppose thatG is a finitep-solvable group and letPε Syl
p
(G). In this note, we prove that the character table ofG determines ifN
G(itP)/P is abelian.
Research partially supported by DGICYT. 相似文献
94.
Continuous counter-current chromatographic separation has been carried out in a simulated moving bed system (SMB). We have worked with a SMB pilot plant (8 columns, 4.4 litres of resin each) which allows the continuous withdrawal of two different fractions. A mixture of glucose-fructose has been separated. To calculate the concentration profile within the separator an axial dispersed plug flow model and an equilibrium stage model have been employed; software has been created to simulate the behaviour of the separator. The necessary parameters of the mode: the adsorption equilibrium constant, the height equivalent to a theoretical plate and the bed voidage, have been acquired experimentally from elution chromatography measurements. The results calculated by simulation give a good representation of the experimental concentration profiles; other separations like xylitol-arabitol have been simulated. The influence of some factors like desorbent flow-rate, feed flow-rate and the bed voidage have been studied using the software. Once the system has worked in a two withdrawal way, an extension of the pilot plant has been constructed so as to obtain a third one. The necessary parameters of the three withdrawal model will be studied. 相似文献
95.
Juan F. Navarro Ibrahim Belgharbi María del Carmen Martínez-Belda 《Mathematical Methods in the Applied Sciences》2023,46(1):1032-1044
In this paper, we have performed a numerical investigation of the escape of a particle from two different dynamical systems with the same number of exit channels. We have chosen specific values of the parameters of the systems so that the openings of the potential well in both systems are approximately of the same size. We have found that, in the galactic system, the distribution of the times of escape follows a sequential pattern that has never been detected before. Moreover, we have proved that this pattern is directly related to the geometry of the stable manifolds to the Lyapunov orbits located at the openings of the potential. Finally, we have shown that the different nature of the two systems affects the way the escape occurs, due to the difference in the geometry of the manifolds to the Lyapunov orbits in both systems. 相似文献
96.
Synthesis of an [(NHC)2Pd(SiMe3)2] Complex and Catalytic cis‐Bis(silyl)ations of Alkynes with Unactivated Disilanes 下载免费PDF全文
Melvyn B. Ansell Dr. Debbie E. Roberts Prof. F. Geoffrey N. Cloke Dr. Oscar Navarro Dr. John Spencer 《Angewandte Chemie (International ed. in English)》2015,54(19):5578-5582
The novel complex cis‐[(ITMe)2Pd(SiMe3)2 (ITMe=1,3,4,5‐tetramethylimidazol‐2‐ylidene) has been synthesized by mild oxidative cleavage of Me3SiSiMe3 using [(ITMe)2Pd0]. The use of this complex as precatalyst for the cis‐bis(silyl)ation of alkynes using unactivated disilanes is reported. 相似文献
97.
Dr. Concha Bosch‐Navarro Zachary P. L. Laker Helen R. Thomas Alexander J. Marsden Dr. Jeremy Sloan Dr. Neil R. Wilson Dr. Jonathan P. Rourke 《Angewandte Chemie (International ed. in English)》2015,54(33):9560-9563
Atomic‐resolution transmission electron microscopy was used to identify individual Au9 clusters on a sulfur‐functionalized graphene surface. The clusters were preformed in solution and covalently attached to the surface without any dispersion or aggregation. Comparison of the experimental images with simulations allowed the rotational motion, without lateral displacement, of individual clusters to be discerned, thereby demonstrating a robust covalent attachment of intact clusters to the graphene surface. 相似文献
98.
Potential of prodendronic polyamines with modulated segmental charge density as novel coating for fast and efficient analysis of peptides and basic proteins by CE and CE‐MS 下载免费PDF全文
Tanize Acunha Clara Ibáñez María Isabel Pascual Reguera Mariagiovanna Sarò Rodrigo Navarro Juan Alfonso Redondo Helmut Reinecke Alberto Gallardo Carolina Simó Alejandro Cifuentes 《Electrophoresis》2015,36(14):1564-1571
In this work, the suitability of a new polymer family has been investigated as capillary coatings for the analysis of peptides and basic proteins by CE. This polymer family has been designed to minimize or completely prevent protein–capillary wall interactions and to modify the EOF. These coating materials are linear polymeric chains bearing as side cationizable moiety a dentronic triamine derived from N,N,N’,N’‐tetraethyldiethylenetriamine (TEDETA), which is linked to the backbone through a spacer (unit labeled as TEDETAMA). Four different polymers have been prepared and evaluated: a homopolymer which comprised only of those cationizable repetitive units of TEDETAMA, and three copolymers that randomly incorporate TEDETAMA together with neutral hydrosoluble units of N‐(2‐hydroxypropyl) methacrylamide (HPMA) at different molar percentages (25:75, 50:50 and 75:25). It has been demonstrated that the composition of the copolymers influences the EOF and therefore the separation of the investigated biopolymers. Among the novel polymers studied, poly‐(TEDETAMA‐co‐HPMA) 50:50 copolymer was successfully applied as coating material of the inner capillary surface in CE‐UV and CE‐MS, providing EOF reversing together with fast and efficient baseline separation of peptides and basic proteins. Finally, the feasibility of the polymer‐coated capillary was shown through the analysis of lysozyme in a cheese sample. 相似文献
99.
100.
Suppose that G is a finite group and let H be a proper subgroup of G. Then the restriction map from the characters of G to the characters of H is never injective. 相似文献