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111.
Abazov VM Abbott B Abolins M Acharya BS Adams M Adams T Agelou M Agram JL Ahn SH Ahsan M Alexeev GD Alkhazov G Alton A Alverson G Alves GA Anastasoaie M Andeen T Anderson S Andrieu B Anzelc MS Arnoud Y Arov M Askew A Asman B Assis Jesus AC Atramentov O Autermann C Avila C Ay C Badaud F Baden A Bagby L Baldin B Bandurin DV Banerjee P Banerjee S Barberis E Bargassa P Baringer P Barnes C Barreto J Bartlett JF Bassler U Bauer D Bean A Begalli M Begel M Belanger-Champagne C Bellantoni L Bellavance A 《Physical review letters》2006,97(15):151804
We present a search for associated Higgs boson production in the process pp-->WH-->WWW*-->l;+/-nul'+/-nu'+X in final states containing two like-sign isolated electrons or muons (e+/-e;+/-, e+/-micro+/-, or micro+/-micro+/-). The search is based on D0 run II data samples corresponding to integrated luminosities of 360-380 pb-1. No excess is observed over the predicted standard model background. We set 95% C.L. upper limits on sigma(pp-->WH)xBr(H-->WW*) between 3.2 and 2.8 pb for Higgs boson masses from 115 to 175 GeV. 相似文献
112.
Matias?NavarroEmail authorView authors OrcID profile Oscar?Palmas Didier?A.?Solis 《Mediterranean Journal of Mathematics》2018,15(6):215
In this paper, we develop the notion of screen isoparametric hypersurface for null hypersurfaces of Robertson–Walker spacetimes. Using this formalism we derive Cartan identities for the screen principal curvatures of null screen isoparametric hypersurfaces in Lorentzian space forms and provide a local characterization of such hypersurfaces. 相似文献
113.
Lilian R. Avila Emerson H. de Faria Katia J. Ciuffi Eduardo J. Nassar Paulo S. Calefi Miguel A. Vicente Raquel Trujillano 《Journal of colloid and interface science》2010,341(1):186-193
Functionalization of Brazilian São Simão kaolinite and Spanish Yunclillos saponite with the alkoxysilanes 3-aminopropyltriethoxysilane and 3-mercaptopropyltrimethoxysilane is reported. The resulting hybrids were characterized by X-ray diffraction, thermal analysis, infrared absorption spectroscopy, and scanning electron microscopy, which demonstrated the effectiveness of the interlamellar grafting process. The X-ray diffractograms revealed incorporation of the alkoxide molecules into the interlayer space of the clays. The displacement of the stretching bands of interlayer hydroxyls in the infrared spectra of the modified kaolinites and the increased intensity of the Mg–OH vibrations in the spectra of the modified saponites confirmed the functionalization of the clays. The thermal behavior of the organoclays confirmed the stability of the hybrids, which was dependent on the clay used for preparation of the materials. 相似文献
114.
Matias Quiroz Minh-Ngoc Tran Mattias Villani Robert Kohn 《Journal of computational and graphical statistics》2018,27(1):12-22
The complexity of the Metropolis–Hastings (MH) algorithm arises from the requirement of a likelihood evaluation for the full dataset in each iteration. One solution has been proposed to speed up the algorithm by a delayed acceptance approach where the acceptance decision proceeds in two stages. In the first stage, an estimate of the likelihood based on a random subsample determines if it is likely that the draw will be accepted and, if so, the second stage uses the full data likelihood to decide upon final acceptance. Evaluating the full data likelihood is thus avoided for draws that are unlikely to be accepted. We propose a more precise likelihood estimator that incorporates auxiliary information about the full data likelihood while only operating on a sparse set of the data. We prove that the resulting delayed acceptance MH is more efficient. The caveat of this approach is that the full dataset needs to be evaluated in the second stage. We therefore propose to substitute this evaluation by an estimate and construct a state-dependent approximation thereof to use in the first stage. This results in an algorithm that (i) can use a smaller subsample m by leveraging on recent advances in Pseudo-Marginal MH (PMMH) and (ii) is provably within O(m? 2) of the true posterior. 相似文献
115.
Jose A. López‐Barrera Alejandro Avila‐Ortega Juan Morales Jorge Cervantes Roberto Olayo 《应用有机金属化学》2007,21(10):858-861
The surface of quarry stone was modified by continuous plasma polymerization of hexamethyldisiloxane. The hydrophilic surface of the quarry stone was made hydrophobic and impermeable to water. Three different reaction times were analyzed. All of them resulted in the formation of a homogenous layer on the quarry stone surface. Contact angle and FT‐IR analyses show that the hydrophobic character of the surface is due to methyl groups on the surface. The change in the contact angle with temperature and the wetting temperature (Tw) are also discussed. Copyright © 2007 John Wiley & Sons, Ltd. 相似文献
116.
Prosenjit Bose Sébastien Collette Ferran Hurtado Matias Korman Stefan Langerman Vera Sacristán Maria Saumell 《Computational Geometry》2013,46(2):131-139
We consider two classes of higher order proximity graphs defined on a set of points in the plane, namely, the k-Delaunay graph and the k-Gabriel graph. We give bounds on the following combinatorial and geometric properties of these graphs: spanning ratio, diameter, connectivity, chromatic number, and minimum number of layers necessary to partition the edges of the graphs so that no two edges of the same layer cross. 相似文献
117.
118.
R. Jeyaraman Cooksley Baldwin Jawaharsingh S. Avila K. Ganapathy Ernest L. Eliel Muthiah Manoharan Susan Morris-Natschke W. R. Kenan 《Journal of heterocyclic chemistry》1982,19(3):449-458
The 13C nmr spectra of 4 cis-2,4-diphenyl-3-azabicyclo[3.3.1]nonanes, 11 cis-2,4-diaryl-3-azabicyclo[3.3.1]-nonan-9-ones, 26 cis-2,4-diaryl-3-azabicyclo[3.3.1]-nonan-9-ols or acetates thereof, 5 cis-2,4-diaryl-3-azabi-cyclo[4.3.1]decan-10-ones or -10-ols and 5 cis-2,4-diphenyl-3-aza-7-thiabicyclo[3.3.1]nonan-9-ones, -9-ols or 9-yl acetates have been recorded. Except for the 7-thia compounds, which appear to exist mainly in the configuration and conformation with the nitrogen-containing ring in the boat form, these compounds seem to exist overwhelmingly in chair-chair conformations. The configuration of the 9-ols and their acetates (syn or anti to the nitrogen-containing ring) has been deduced from the spectra. In a number of cases, the structures assigned differ from those earlier postulated. Broadening of one set of aryl signals (probably those due to the ortho carbons) in the case of N-methyl (but not N-H) compounds without ortho substituents is ascribed to restricted phenyl rotation. 相似文献
119.
J.Matias Reinoso Hans‐Joachim Muhr Frank Krumeich Fabian Bieri Reinhard Nesper 《Helvetica chimica acta》2000,83(8):1724-1733
Vanadium oxide nanotubes (Cn‐VOx‐NTs) contain α‐monoamines (CnH2n+1NH2 with 4≤n≤22) as templates intercalated between crystalline VOx layers comprising multilayer tube walls. The present study reveals that a large proportion of the amines can easily be exchanged by metal cations. The tubular morphology is not affected by this reaction, but the distance between the VOx layers, i.e., 2.8 nm in C12‐VOxNTs, decreases in the reaction product to 0.9 – 1.2 nm, depending on the metal salt actually applied. Alkali (Na+, K+), alkaline‐earth (Mg2+, Ca2+, Sr2+), and transition‐metal salts (Fe2+, Co2+, Ni2+, Cu2+) have successfully been intercalated. This reaction is partly reversible since intercalated sodium cations can be resubstituted by dodecylamine. This exchange produces again C12‐VOx‐NTs with the original inter‐layer spacing. However, this release is successful only when sodium is complexed by a crown ether. Under these reaction conditions, even a cyclic uptake and release of Na+ and amine, respectively, accompanied by a corresponding shrinkage and widening of the inter‐layer distance, is observed while the tubular structure is widely preserved. Furthermore, a distinct selectivity of the metal‐cation exchange has been observed. 相似文献
120.
Stefano De Benedetti Camilla Leogrande Francesco Castagna Giuditta C. Heinzl Matias Pasquali Alessandro L. Heinzl Daniela Lupi Alessio Scarafoni 《Molecules (Basel, Switzerland)》2022,27(1)
The present work aimed to characterize the molecular relationships between structure and function of the seed storage protein β-vignin, the vicilin storage protein of cowpea (Vigna unguiculata, l. Walp) seeds. The molecular characterization of β-vignin was carried out firstly by assessing its thermal stability, under different conditions of pH and ionic strength, by thermal shift assay (TSA) using SYPRO Orange fluorescent dye. Secondly, its aggregation propensity was evaluated using a combination of chromatographic and electrophoretic techniques. Two forms of β-vignin were considered: the native form purified from mature quiescent seeds, and a stable breakdown intermediate of 27 kDa produced while seeds germinate. TSA is a useful tool for determining and following over time the structural changes that occur to the protein during germination. The main result was the molecular characterization of the 27 kDa intermediate breakdown polypeptide, which, to the best of our knowledge, has never been described before. β-vignin seems to retain its trimeric conformation despite the evident degradation of its polypeptides. 相似文献