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91.
Gómez L Ruiz JJ Camacho L Rodríguez-Amaro R 《Langmuir : the ACS journal of surfaces and colloids》2005,21(1):369-374
This paper reports a new mathematical model for consecutive two-dimensional phase transitions that accounts for the chronoamperometric behavior observed in the formation of electrochemical phases by 4,4'-bipyridyl cation radical (BpyH(2)(*)(+)) on mercury in aqueous iodide solutions. Also, a new interpretation for the induction time is proposed. 相似文献
92.
Hanz Y. Ramirez Angela S. Camacho 《Physica E: Low-dimensional Systems and Nanostructures》2008,40(9):2937-2940
In this work, we calculate the temporal evolution of electronic states under AC electric fields. We do that by obtaining the eigenenergies and wave functions of states of the first two minibands for arrays of 10 cylindrical quantum dots, both vertically and laterally coupled, which exhibit notable difference in their symmetry levels and coupling magnitudes. We observe an important dependence of the Rabi amplitude on the wave function symmetry and the coupling magnitude, and conclude that Rabi oscillations at the terahertz range are best suited for the higher coupling between dots. 相似文献
93.
94.
[structure: see text] Herein we describe an efficient synthesis of cyclophanes comprised of intra-annular nitrogen functional groups through a template-promoted cyclization by ring-closing metathesis (RCM). The synthesis proceeds through condensation of meta-styryl anilines with acenaphthenequinone to form the templates, followed by RCM with Grubb's second-generation catalyst to afford cyclophanes with internal alpha-diimine functionality. Prolonged hydrogenation efficiently removes the template to provide a macrocycle containing the diamine functionality. 相似文献
95.
1H and 13C NMR spectral assignment of N,N′‐disubstituted thiourea and urea derivatives active against nitric oxide synthase
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Mariem Chayah M. Encarnación Camacho M. Dora Carrión Miguel A. Gallo 《Magnetic resonance in chemistry : MRC》2016,54(10):793-799
The 1H and 13C NMR resonances of seventeen N‐alkyl and aryl‐N′‐[3‐hydroxy‐3‐(2‐nitro‐5‐substitutedphenyl)propyl]‐thioureas and ureas ( 1–17 ), and seventeen N‐alkyl or aryl‐N′‐[3‐(2‐amino‐5‐substitutedphenyl)‐3‐hydroxypropyl]‐thioureas and ureas ( 18–34 ), designed as NOS inhibitors, were assigned completely using the concerted application of one‐ and two‐dimensional experiments (DEPT, HSQC and HMBC). NOESY studies confirm the preferred conformation of these compounds. Copyright © 2016 John Wiley & Sons, Ltd. 相似文献
96.
M. Dora Carrión Mariem Chayah Duane Choquesillo‐Lazarte Miguel A. Gallo Antonio Espinosa Antonio Entrena M. Encarnación Camacho 《Magnetic resonance in chemistry : MRC》2012,50(1):58-61
The 13 C NMR resonances of 19 1‐acyl‐3‐(2‐nitro‐5‐substitutedphenyl)‐4,5‐dihydro‐1H‐pyrazoles, and 19 1‐acyl‐3‐(2‐amino‐5‐substituted)‐4,5‐dihydro‐1H‐pyrazoles, were completely assigned using the concerted application of one‐ and two‐dimensional NMR experiments (DEPT, gs‐HSQC and gs‐HMBC). Copyright © 2012 John Wiley & Sons, Ltd. 相似文献
97.
We study the strategic behavior of two countries facing transboundary CO2 pollution under a differential game setting. In our model, the reduction of CO2 concentration occurs through the carbon capture and storage process, rather than through the adoption of cleaner technologies. Furthermore, we first provide the explicit short-run dynamics for this dynamic game with symmetric open-loop and a special Markovian Nash strategy. Then, we compare these strategies at the games’ steady states and along some balanced growth paths. Our results show that if the initial level of CO2 is relatively high, state dependent emissions reductions can lead to higher overall environmental quality, hence, feedback strategy leads to less social waste. 相似文献
98.
J. M. Navarrete G. Espinosa J. I. Golzarri G. Müller M. A. Zúñiga M. Camacho 《Journal of Radioanalytical and Nuclear Chemistry》2014,299(1):843-847
During a time period little longer than 60 years, it has been created a radioactive pollution background over the natural one, which started in 1945 and it has been growing up since then, due to several nuclear tests, minor nuclear reactors failure and four major accidents: Wind Scale, Three Mile Island, Chernobyl and Fukushima. This radioactive polluting background can be easily detected through 137Cs fission product, which by the effect of wind, river currents and rain has been accumulated in marine sediments, mainly because sea represents about 80 % of earth’s surface. Since energy demand has been growing up with no interruption during last two centuries, and nuclear energy seems to be the largest available source, it is very likely a great expansion of nuclear energy during twenty-first century. So, this paper presents results obtained in strategic points of the two large littorals in Mexico: Gulf and Pacific Ocean, as an attempt to establish there some figure to evaluate the present radioactive pollution. An adequate figure to do it, seems to be the quotient of activity per gram of 137Cs in marine sediments (Bq137Cs/g), divided by activity per gram of 40K natural radioactivity (Bq40K/g). When this result is multiplied by 100 the percentage of polluting radioactivity (137Cs) related to natural radioactivity (40K) is obtained. This percentage seems to be useful to evaluate the importance of radioactive pollution from 4 points of view: a) calculate the extent of already radioactive pollution present in the seas of world; b) avoid the panic in case of nuclear accidents, c) what will be the growing up rate in the future; d) if it is possible to keep one decreasing rate at same decaying rate of 137Cs (t1/2 = 30.07 years), since from 1945, starting time of radioactive pollution, it has decayed only about 2.2 half lives. 相似文献
99.
Pan ZH Camacho J Upton MH Fedorov AV Howard CA Ellerby M Valla T 《Physical review letters》2011,106(18):187002
We have performed photoemission studies of the electronic structure in LiC(6) and KC(8), a nonsuperconducting and a superconducting graphite intercalation compound, respectively. We have found that the charge transfer from the intercalant layers to graphene layers is larger in KC(8) than in LiC(6), opposite of what might be expected from their chemical composition. We have also measured the strength of the electron-phonon interaction on the graphene-derived Fermi surface to carbon derived phonons in both materials and found that it follows a universal trend where the coupling strength and superconductivity monotonically increase with the filling of graphene π(*) states. This correlation suggests that both graphene-derived electrons and graphene-derived phonons are crucial for superconductivity in graphite intercalation compounds. 相似文献
100.
Adare A Afanasiev S Aidala C Ajitanand NN Akiba Y Al-Bataineh H Alexander J Aoki K Aramaki Y Atomssa ET Averbeck R Awes TC Azmoun B Babintsev V Bai M Baksay G Baksay L Barish KN Bassalleck B Basye AT Bathe S Baublis V Baumann C Bazilevsky A Belikov S Belmont R Bennett R Berdnikov A Berdnikov Y Bickley AA Bok JS Boyle K Brooks ML Buesching H Bumazhnov V Bunce G Butsyk S Camacho CM Campbell S Chen CH Chi CY Chiu M Choi IJ Choudhury RK Christiansen P Chujo T Chung P Chvala O Cianciolo V Citron Z 《Physical review letters》2011,107(25):252301
Flow coefficients ν(n) for n=2, 3, 4, characterizing the anisotropic collective flow in Au+Au collisions at √s(NN)=200 GeV, are measured relative to event planes Ψ(n), determined at large rapidity. We report ν(n) as a function of transverse momentum and collision centrality, and study the correlations among the event planes of different order n. The ν(n) are well described by hydrodynamic models which employ a Glauber Monte Carlo initial state geometry with fluctuations, providing additional constraining power on the interplay between initial conditions and the effects of viscosity as the system evolves. This new constraint can serve to improve the precision of the extracted shear viscosity to entropy density ratio η/s. 相似文献