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排序方式: 共有302条查询结果,搜索用时 15 毫秒
171.
Elke-Caroline Aschenauer Ian Balitsky Leslie Bland Stanley J. Brodsky Matthias Burkardt Volker Burkert Jian-Ping Chen Abhay Deshpande Markus Diehl Leonard Gamberg Matthias Grosse Perdekamp Jin Huang Charles Hyde Xiangdong Ji Xiaodong Jiang Zhong-Bo Kang Valery Kubarovsky John Lajoie Keh-Fei Liu Ming Liu Simonetta Liuti Wally Melnitchouk Piet Mulders Alexei Prokudin Andrey Tarasov Jian-Wei Qiu Anatoly Radyushkin David Richards Ernst Sichtermann Marco Stratmann Werner Vogelsang Feng Yuan 《The European Physical Journal A - Hadrons and Nuclei》2017,53(4):71
172.
Simona Baroni Maria Rosaria Ruggiero Silvio Aime Simonetta Geninatti Crich 《Magnetic resonance in chemistry : MRC》2019,57(10):845-851
1H Fast Field Cycling NMR (FFC-NMR) relaxometry is proposed as a powerful method to investigate tumour stroma in vivo upon the administration of a Gd-based contrast agent. To perform this study, an FFC-NMR equipment endowed with a wide bore magnet was used for the acquisition of Nuclear Magnetic Resonance Dispersion profiles on healthy muscle and tumour tissue in living mice. At magnetic field strengths < of ca. 1 MHz, the differences in the relaxation rates of the intra and extracellular compartment become of the same order of magnitude of the exchange rate across the cellular membranes. Under this condition, the water exchange rate between the two compartments yields to a biexponential magnetization recovery that can be analysed by fitting the experimental data with the two-Site eXchange (2SX) model. Using this model, it was possible to obtain, for the two compartments, both relaxation properties and water kinetic constants for water exchange across cell membranes. The method allowed us to determine the effect of the “matrix” on the water proton relaxation times and, in turn, to get some insights of the composition of this compartment, till now, largely unknown. 相似文献
173.
Saeed Ahmad Heli Honkanen Simonetta Liuti Swadhin K. Taneja 《The European Physical Journal C - Particles and Fields》2009,63(3):407-421
We propose a physically motivated parameterization for the unpolarized generalized parton distributions, H and E, valid at both zero and non-zero values of the skewness variable, ζ. Our approach follows a previous detailed study of the
ζ=0 case where H and E were determined using constraints from simultaneous fits of the experimental data on both the nucleon elastic form factors
and the deep inelastic structure functions in the non-singlet sector. Additional constraints at ζ≠0 are provided by lattice
calculations of the higher moments of generalized parton distributions. We illustrate a method for extracting generalized
parton distributions from lattice moments based on a reconstruction using sets of orthogonal polynomials. The inclusion in
our fit of data on Deeply Virtual Compton Scattering is also discussed. Our method provides a step towards an extraction of
generalized distributions based on a global fit of the available data within the given set of constraints. 相似文献
174.
De Fazio D Aquilanti V Cavalli S Aguilar A Lucas JM 《The Journal of chemical physics》2006,125(13):133109
In this paper we present integral cross sections (in the 5-220 meV collision energy range) and rate constants (in the 100-300 K range of temperature) for the F+HD reaction leading to HF+D and DF+H. The exact quantum reactive scattering calculations were carried out using the hyperquantization algorithm on an improved potential energy surface which incorporates the effects of open shell and fine structure of the fluorine atom in the entrance channel. The results reproduce satisfactorily molecular beam scattering experiments as well as chemical kinetics data for both the HF and DF channels. In particular, the agreement of the rate coefficients and the vibrational branching ratios with experimental measurements is improved with respect to previous studies. At thermal and subthermal energies, the rates are greatly influenced by tunneling through the reaction barrier. Therefore exchange of deuterium is shown to be penalized with respect to exchange of hydrogen, and the isotopic branching exhibits a strong dependence on translational energy. Also, it is found that rotational excitation of the reactant HD molecule enhances the production of HF and decreases the reactivity at the D end, obtaining insight on the reaction stereodynamics. 相似文献
175.
Narcisa Mandras Janira Roana Daniela Scalas Simonetta Del Re Lorenza Cavallo Valeria Ghisetti Vivian Tullio 《Molecules (Basel, Switzerland)》2021,26(16)
The epidemiology of yeast infections and resistance to available antifungal drugs are rapidly increasing, and non-albicans Candida species and rare yeast species are increasingly emerging as major opportunistic pathogens. In order to identify new strategies to counter the threat of antimicrobial resistant microorganisms, essential oils (EOs) have become an important potential in the treatment of fungal infections. EOs and their bioactive pure compounds have been found to exhibit a wide range of remarkable biological activities. We investigated the in vitro antifungal activity of nine commercial EOs such as Thymus vulgaris (thyme red), Origanum vulgare (oregano), Lavandula vera (lavender), Pinus sylvestris (pine), Foeniculum vulgare (fennel), Melissa officinalis (lemon balm), Salvia officinalis (sage), Eugenia caryophyllata (clove) and Pelargonium asperum (geranium), and some of their main components (α-pinene, carvacrol, citronellal, eugenol, γ-terpinene, linalool, linalylacetate, terpinen-4-ol, thymol) against non-albicans Candida strains and uncommon yeasts. The EOs were analyzed by GC-MS, and their antifungal properties were evaluated by minimum inhibitory concentration and minimum fungicidal concentration parameters, in accordance with CLSI guidelines, with some modifications for EOs. Pine exhibited strong antifungal activity against the selected non-albicans Candida isolates and uncommon yeasts. In addition, lemon balm EOs and α-pinene exhibited strong antifungal activity against the selected non-albicans Candida yeasts. Thymol inhibited the growth of all uncommon yeasts. These data showed a promising potential application of EOs as natural adjuvant for management of infections by emerging non-albicans Candida species and uncommon pathogenic yeasts. 相似文献
176.
A systematic study of the Robinson-Trautman metrics in the asymptotic future is presented. As a by-product another technique, that could be used for determining existence of solutions of the Robinson-Trautman equation, is found. All these metrics present an exponential asymptotic limit to the Schwarzschild metric in this regime. 相似文献
177.
Following previous work on Pt(111)/hydrogen system, SCF MO pseudopotential calculations have been done for the case of atomic oxygen chemisorption on Pd(111), using clusters of up to four metal atoms. No site preference is found for oxygen chemisorption, and the chemisorption bond appears to involve only nearest-neighbor metal atoms. The use of a double-zeta 4d function for the metal results in significant changes in the bonding pattern with respect to single-zeta. 相似文献
178.
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180.