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91.
Hua‐Huai Chern María‐Inés Fernández‐Camacho Hsien‐Kuei Hwang Conrado Martínez 《Random Structures and Algorithms》2014,44(1):67-108
An unusual and surprising expansion of the form as , is derived for the probability pn that two randomly chosen binary search trees are identical (in shape, hence in labels of all corresponding nodes). A quantity arising in the analysis of phylogenetic trees is also proved to have a similar asymptotic expansion. Our method of proof is new in the literature of discrete probability and the analysis of algorithms, and it is based on the logarithmic psi‐series expansions for nonlinear differential equations. Such an approach is very general and applicable to many other problems involving nonlinear differential equations; many examples are discussed in this article and several attractive phenomena are discovered.Copyright © 2012 Wiley Periodicals, Inc. Random Struct. Alg., 44, 67–108, 2014 相似文献
92.
93.
94.
Antonia Camacho Montserrat Montaña Isabel Vallés Ricard Devesa Raquel Céspedes-Sánchez Isabel Serrano 《Journal of Radioanalytical and Nuclear Chemistry》2013,295(1):297-306
22 sludge samples were analyzed from three municipal wastewater treatment plants to assess both the occurrence and the temporal behavior of radioactivity during 8 sampling campaigns carried out over the period 2007–2009. As regards natural gamma emitters radionuclides from the natural 238U series (such as 234Th, 214Pb, 214Bi, 210Pb) and the 232Th series (such as 228Ac, 212Pb, 212Bi and 208Tl) and other natural gamma emitters such as 7Be, 210Pbu or 40K were measured. In the case of man-made radionuclides small amounts of 137Cs were found, while significant amounts of 131I were detected in some samples. Correlations were found between radionuclides with the same origin. No seasonal variation for the 238U and 232Th series was found in the studied period but 7Be and 210Pbu showed seasonal variation that was explained by the monthly rainfall. The internal and external hazard indices were calculated and the results indicate that the radiological characteristics of the sludge do not present a significant radiological risk and make them suitable for future applications. 相似文献
95.
M. Dora Carrión Luisa C. López‐Cara Mariem Chayah Duane Choquesillo‐Lazarte Miguel A. Gallo Antonio Espinosa Antonio Entrena M. Encarnación Camacho 《Magnetic resonance in chemistry : MRC》2012,50(7):515-522
The 1H and 13C NMR resonances of twenty‐seven 2,2‐dimethyl‐5‐(2‐nitrophenyl‐5‐substituted)‐2,3‐dihydro‐1,3,4‐thiadiazoles, and twenty‐seven 3‐acyl‐5‐(2‐amino‐5‐substituted)‐2,2‐dimethyl‐2,3‐dihydro‐1,3,4‐thiadiazoles were assigned completely using the concerted application of one‐dimensional and two‐dimensional experiments (DEPT, HMQC and HMBC). NOESY experiments, X‐ray crystallography and conformational analysis confirm the preferred conformation of these compounds. Copyright © 2012 John Wiley & Sons, Ltd. 相似文献
96.
Carlos Camacho‐Camacho Monique Biesemans Ingrid Verbruggen Rudolph Willem 《应用有机金属化学》2005,19(3):343-346
The reactivity and catalytic potential of the tin salicylaldoximate cluster [(Me2Sn)2(Me2SnO)(OCH3) (HONZO)(ONZO)] ( 1 ), with HONZOH = o‐HON?CH? C6H4OH, on the acylation reaction of various alcohols with ethyl acetate is reported. The catalyst is active toward primary and unhindered secondary alcohols, but inefficient toward tertiary and secondary bulky alcohols and phenols. A possible mechanism for the transesterification reaction catalyzed by 1 , accounting for the influence of steric factors, is proposed. Copyright © 2005 John Wiley & Sons, Ltd. 相似文献
97.
C. Tomas J.P. Girardeau-Montaut M. Afif M. Romand M. Charbonnier T.M. Duc 《Applied Physics A: Materials Science & Processing》1997,64(5):467-471
3+ :YAG laser with 5th harmonic generator, generating 16 ps duration pulses at 213 nm, with energies up to 0.5 mJ. Experimental results concerning
the action of laser pulses, as well as the effects of residual pressure on the cleanliness of the photocathodes surface are
presented and discussed. Influence of laser pulses and residual pressure on the work function of the metal are also investigated.
Received: 15 April 1996/Accepted: 5 November
1996 相似文献
98.
Tomas de Paulis Nabil El Tayar Pierre-Alain Carrupt Bernard Testa Han van de Waterbeemd 《Helvetica chimica acta》1991,74(2):241-254
A large series of orthopramides (= 2-methoxybenzamides), 6-methoxysalicylamides, and 2,6-dimethoxy-benzamides were examined for their affinity to the dopamine D2 receptor. The binding data were correlated with physicochemical parameters and 13C-NMR chemical shifts using the cross-validated partial least-squares method and multiple linear regression analysis. The results quantitate the influence of electronic factors and lipophilicity to D2 receptor binding. They also show that the N-[(1-ethylpyrroIidin-2-yl)methyl] and N-(1-benzylpiperidin-4-yl) side-chains affect the mode of binding of these compounds. 相似文献
99.
James Camacho Jr. 《Periodica Mathematica Hungarica》1995,31(2):113-121
The subset of lattice regular zero-one valued measures on an algebra generated by a lattice (a Wallman-type space) which integrates all lattice continuous functions on an arbitrary setX is introduced and some properties of it are presented.Then repleteness of certain Wallman spaces is considered and used in finally establishing conditions whereby the space of lattice regular zero-one valued measures on the algebra generated by a lattice which are countably additive (a Wallman-type space) is realcompact. 相似文献
100.
Gluconobacter oxydans bacteria exhibit a unique metabolism for quick and incomplete oxidation of a wide range of different compounds (aldoses, ketoses, mono- and poly-alcohols, etc.). Such biotransformation efficiency with simple biomass production led to the industrial applications of these bacteria in the production of several important commodities. Their respiratory activity can also be successfully studied and used in the field of bioelectrochemistry. The main aim of this review is to present various strategies to improve selectivity of assays using intact/treated cells of G. oxydans, to introduce the application of G. oxydans-based biosensors in selective monitoring of analytes during biotransformation processes and to provide information about utilizable sugars in fermentation media or in biological oxygen demand value determination. The final part of the review describes potential application of G. oxydans cells in the generation of electricity from complex fuels within microbial fuel cells by advanced direct electron transfer route between bacterial cells and electrodes. 相似文献