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排序方式: 共有138条查询结果,搜索用时 390 毫秒
61.
Leandro Javier Salvo Lorenzo Coiana Cecilia Dobrecky Valeria Tripodi Sabrina Flor Silvia Lucangioli 《Electrophoresis》2019,40(12-13):1719-1721
A simple and highly sensitive CE–UV method was applied in the determination of l ‐ctrulline, which was developed from an oral formulation for pediatric use. The novel method was based on the analysis of l ‐citrulline for direct ultraviolet detection at 198 nm. The BGE consisted of 10 mM sodium tetraborate and 50 mM SDS at pH 9, and the electrophoretic parameters were optimized. The method was validated in terms of specificity, linearity, LOD, LOQ, precision, accuracy, and robustness. The LOD and LOQ obtained were 1.36 and 4.54 μg/mL, respectively. In addition, the method offers higher sensitivity and specificity compared with the results obtained from HPLC method using UV‐detectors, in which l‐ citrulline needs to be derivatizated. Furthermore, low cost and simplicity of the system allowed the rapid and simple quantitation of l‐ citrulline in the oral formulation for quality control and stability indicated method. 相似文献
62.
Ajaka J Assafiri Y Bartalini O Bellini V Bouchigny S Castoldi M D'Angelo A Didelez JP Di Salvo R Döring M Fantini A Fichen L Gervino G Ghio F Girolami B Giusa A Guidal M Hourany E Kunne R Lapik A Sandri PL Moricciani D Mushkarenkov A Nedorezov V Oset E Randieri C Rudnev N Russo G Schaerf C Sperduto M Sutera M Turinge A 《Physical review letters》2008,100(5):052003
The analysis of the gammap-->etapi(0)p reaction has been performed using data from the GRAAL experiment. The total and differential cross sections and the beam asymmetry have been obtained from threshold up to 1.5 GeV of beam energy. The two resonances S11(1535) and Delta(1700) are expected to be excited in the intermediate states of this reaction. The results are used to test predictions based on the assumption that both resonances are dynamically generated from the meson-baryon interaction provided by chiral Lagrangians. The term involving the Delta(1700) excitation, followed by the decay into etaDelta(1232), is found to be dominant. 相似文献
63.
A.C. Gossard F.J. Di Salvo W.E. Falconer T.M. Rice J.M. Voorhoeve H. Yasuoka 《Solid State Communications》1974,14(11):1207-1211
Magnetic susceptibility and nuclear magnetic resonance above and below the ordering temperature show that VF4 is an , 3d1 canted antiferromagnet with a transition temperature near 28°K and a canting angle of ~ .02 rad. The compound is not an example of a proposed nonmagnetic singlet ground state of resonating covalent bonds. 相似文献
64.
H.P. Fredricksen H.L. Salvo M. Levy R.H. Hammond T.H. Geballe 《Physics letters. A》1980,75(5):389-391
The attenuation of 660 MHz surface acoustic waves propagating in a thin film of Nb3Sn 5000 Å thick has been measured as a function of temperature from 4.2 K to 16 K. The A 15 Nb3Sn, electron-beam codeposited on YZ lithium niobate and annealed at 700°C, was studied using 5.1 μm wavelength interdigital electrodes. The film revealed a transition temperature of 14.2 ± 0.1 K and using the BCS theory, an energy gap 2Δ(0) = 3.5 kBTc. 相似文献
65.
F.J. Di Salvo B.G. Bagley J.M. Voorhoeve J.V. Waszczak 《Journal of Physics and Chemistry of Solids》1973,34(8):1357-1362
A new polymorph of the layered compound tantalum disulfide, 4Hb-TaS2, has been prepared in single crystal form. Measurements of magnetic susceptibility, electrical resistivity, and differential heat capacity show two first order transitions at 20 and 315°K. The 315°K transition involves only a small volume and enthalpy change, as in the previously observed transitions of another polymorph, 1T-TaS2. The resistivity measurements show metallic like conductivity, as in 2H-TaS2, when the current is parallel to the layers, but semiconducting like conductivity, as in 1T-TaS2, when perpendicular to the layers. The properties of 4Hb-TaS2 are moderately well described as a ‘mix’ of those of 1T-TaS2 and 2H-TaS2. 相似文献
66.
Bikiel DE Di Salvo F González Lebrero MC Doctorovich F Estrin DA 《Inorganic chemistry》2005,44(15):5286-5292
The nature of the solute species present in ethereal solutions of LiAlH(4) is of crucial importance for understanding the mechanisms for the reduction of ketones and other functional groups by LiAlH(4). We have employed a combination of theoretical and experimental techniques to investigate the structure of LiAlH(4) in ethereal solutions. Using complexation agents, we measured the IR spectra of LiAlH(4) and AlH(4)(-) in tetrahydrofuran (THF). Hybrid quantum-classical (QM-MM) simulations have also been carried out to compute the IR spectra of associated and dissociated LiAlH(4) species and the free-energy profile for the dissociation process in solution. Our experimental estimate of the dissociation constant in THF is 0.021 +/- 0.002, while the predicted computational value corresponding to a model dimethyl ether solvent is 0.001. The free-energy profile shows only one minimum corresponding to a contact ion pair at a Li-Al separation distance of 3.0 A. These results are consistent with the fact that LiAlH(4) is essentially associated in ethereal solutions forming contact ion pairs. 相似文献
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70.
Pierluigi Salvo Rossi Domenico Ciuonzo Gianmarco Romano Francesco Palmieri 《Wireless Personal Communications》2013,68(4):1351-1364
In this paper we consider a multiple-access scheme in which different users share the same bandwidth and the same pulse, and are discriminated at the receiver on the basis of the received energy using successive decoding. More specifically, we extend the performance analysis from the case of additive white Gaussian noise channels (presented in a previous work Salvo Rossi in Wirel Pers Commun, in press) to the case of fading channels. The presence of channel coefficients introduces a new degree of freedom in the transceiver design: unlike the AWGN case, different ordering among the users provides different transmitted energy, thus different overall system performance. Optimal ordering, in terms of minimum transmitted energy, is derived analytically. Analytical and numerical results, in terms of bit error rate and normalized throughput, are derived for performance evaluation in fading environments with optimal ordering exhibiting significant gains w.r.t. static ordering. 相似文献