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91.
Bergeron DE Musgrave A Ayles VL Gammon RT Silber JA Wright TG 《The Journal of chemical physics》2006,125(14):144319
We have employed (2 + 1) resonance enhanced multiphoton ionization spectroscopy to investigate the 3d and 4s Rydberg states of the NO molecule when bound to the surface of Rg(x) clusters (Rg = rare gas). We observe that the spectra of the NO-Ar(x) species converge in appearance as x increases, and this is discussed in terms of two Rg atoms interacting with the NO+ core, with other Rg atoms being "outside" the Rydberg orbital. We show that the interaction of each of the Rg atoms with the NO is essentially independent for the NO-Rg2 complexes: both by comparing our spectra for Rydberg states of NO-Rg and NO-Rg2, and from the results of ab initio calculations on NO+ - Rg and NO+ - Rg2. In addition, we discuss the disappearance of some electronic bands upon complexation in terms of Franck-Condon factors that are very sensitive to the angular coordinate. We relate our results to those of the bulk by comparing to the previously reported electronic spectroscopy of NO in both Rg matrices and He nanodroplets. 相似文献
92.
Jacobsen RG Koetke DS Adolphsen CE Fujino D Schumm BA Wagner SR Alexander JP Averill D Barish BC Barklow T Barnett BA Blockus D Boyarski A Brabson B Breakstone A Bulos F Burchat PR Burke DL Cence RJ Chapman J Chmeissani M Cords D Coupal DP Dauncey P DeStaebler HC Dorfan JM Drell PS Drewer DC Durrett D Elia R Feldman GJ Field RC Ford WT Fordham C Frey R Gan KK Gero E Gidal G Glanzman T Goldhaber G Gomez Cadenas JJ Gratta G Hanson G Harr R Harral B Harris FA Hayes K Hearty C Heusch CA 《Physical review letters》1991,67(24):3347-3350
93.
Previous work has shown that Benjamin-Feir unstable traveling waves of the complex Ginzburg-Landau equation (CGLE) in two spatial dimensions cannot be stabilized using a particular time-delayed feedback control mechanism known as ‘time-delay autosynchronization’. In this paper, we show that the addition of similar spatial feedback terms can be used to stabilize such waves. This type of feedback is a generalization of the time-delay method of Pyragas [K. Pyragas, Continuous control of chaos by self-controlling feedback, Phys. Lett. A 170 (1992) 421-428] and has been previously used to stabilize waves in the one-dimensional CGLE by Montgomery and Silber [K. Montgomery, M. Silber, Feedback control of traveling wave solutions of the complex Ginzburg Landau equation, Nonlinearity 17 (6) (2004) 2225-2248]. We consider two cases in which the feedback contains either one or two spatial terms. We focus on how the spatial terms may be chosen to select the direction of travel of the plane waves. Numerical linear stability calculations demonstrate the results of our analysis. 相似文献
94.
Concentration and temperature-dependent NMR chemical shifts for maleic anhydride in acetone and benzene solution are interpreted in terms of equilibria between monomers and solvent-solute molecular complexes. Calorimetric heats of dilution and heats of solution give thermodynamic parameters that agree with those determined in the NMR experiments. The thermodynamic parameters obtained are similar for both systems, and it is possible that the previously established role of a ground state complex in the benzene-maleic anhydride photochemical cycloaddition reaction can be extended to the acetone-maleic anhydride photocycloaddition. 相似文献
95.
96.
Abrams GS Adolphsen CE Averill D Ballam J Barish BC Barklow T Barnett BA Bartelt J Bethke S Blockus D Bonvicini G Boyarski A Brabson B Breakstone A Bulos F Burchat PR Burke DL Cence RJ Chapman J Chmeissani M Cords D Coupal DP Dauncey P DeStaebler HC Dorfan DE Dorfan JM Drewer DC Elia R Feldman GJ Fernandes D Field RC Ford WT Fordham C Frey R Fujino D Gan KK Gero E Gidal G Glanzman T Goldhaber G Gomez Cadenas JJ Gratta G Grindhammer G Grosse-Wiesmann P Hanson G Harr R Harral B Harris FA 《Physical review letters》1990,64(12):1334-1337
97.
Calderbank AR; Cameron PJ; Kantor WM; Seidel JJ 《Proceedings London Mathematical Society》1997,75(2):436-480
When m is odd, spreads in an orthogonal vector space of type+(2m + 2,2) are related to binary Kerdock codes and extremalline-sets in 2m + 1 with prescribed angles. Spreads in a 2m-dimensionalbinary symplectic vector space are related to Kerdock codesover Z4 and extremal line-sets in with prescribed angles. These connections involve binary, realand complex geometry associated with extraspecial 2-groups.A geometric map from symplectic to orthogonal spreads is shownto induce the Gray map from a corresponding Z4-Kerdock codeto its binary image. These geometric considerations lead tothe construction, for any odd composite m, of large numbersof Z4-Kerdock codes. They also produce new Z4-linear Kerdockand Preparata codes. 1991 Mathematics Subject Classification:primary 94B60; secondary 51M15, 20C99. 相似文献
98.
Abrams GS Adolphsen CE Averill D Ballam J Barish BC Barklow T Barnett BA Bartelt J Bethke S Blockus D Bonvicini G Boyarski A Brabson B Breakstone A Bulos F Burchat PR Burke DL Cence RJ Chapman J Chmeissani M Cords D Coupal DP Dauncey P DeStaebler HC Dorfan DE Dorfan JM Drewer DC Elia R Feldman GJ Fernandes D Field RC Ford WT Fordham C Frey R Fujino D Gan KK Gero E Gidal G Glanzman T Goldhaber G Gomez Cadenas JJ Gratta G Grindhammer G Grosse-Wiesmann P Hanson G Harr R Harral B Harris FA 《Physical review letters》1989,63(26):2780-2783
99.
Nanoscale Control Over Interfacial Properties in Mixed Reverse Micelles Formulated by Using Sodium 1,4‐bis‐2‐ethylhexylsulfosuccinate and Tri‐n‐octyl Phosphine Oxide Surfactants 下载免费PDF全文
Emmanuel Odella Dr. R. Darío Falcone Prof. Juana J. Silber Prof. Dr. N. Mariano Correa 《Chemphyschem》2016,17(15):2407-2414
The interfacial properties of pure reverse micelles (RMs) are a consequence of the magnitude and nature of noncovalent interactions between confined water and the surfactant polar head. Addition of a second surfactant to form mixed RMs is expected to influence these interactions and thus affect these properties at the nanoscale level. Herein, pure and mixed RMs stabilized by sodium 1,4‐bis‐2‐ethylhexylsulfosuccinate and tri‐n‐octyl phosphine oxide (TOPO) surfactants in n‐heptane were formulated and studied by varying both the water content and the TOPO mole fraction. The microenvironment generated was sensed by following the solvatochromic behavior of the 1‐methyl‐8‐oxyquinolinium betaine probe and 31P NMR spectroscopy. The results reveal unique properties of mixed RMs and we give experimental evidence that free water can be detected in the polar core of the mixed RMs at very low water content. We anticipate that these findings will have an impact on the use of such media as nanoreactors for many types of chemical reactions, such as enzymatic reactions and nanoparticle synthesis. 相似文献
100.
Nucleotides, XXI. Synthesis and Properties of Dihydrouridine-Containing Oligonucleotides Substituted 5,6-dihydrouridine derivatives 1, 5 , and 8 have been used in condensation reactions to form a series of dinucleosidemono- and dinucleosidediphosphotriesters, 13 and 16–22 , respectively. Dihydrouridine-containing fully blocked oligomers have also been obtained by stepwise chain-elongation and block condensations including 5 trimers (25–29) and one pentamer (31) , hexamer (32) and octamer (34) each. The new compounds were characterized by UV and partly CD spectra as well as elementary analyses. NMR spectra prove the structures but are not reported in detail. 相似文献