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201.
Abulencia A Acosta D Adelman J Affolder T Akimoto T Albrow MG Ambrose D Amerio S Amidei D Anastassov A Anikeev K Annovi A Antos J Aoki M Apollinari G Arguin JF Arisawa T Artikov A Ashmanskas W Attal A Azfar F Azzi-Bacchetta P Azzurri P Bacchetta N Bachacou H Badgett W Barbaro-Galtieri A Barnes VE Barnett BA Baroiant S Bartsch V Bauer G Bedeschi F Behari S Belforte S Bellettini G Bellinger J Belloni A Haim EB Benjamin D Beretvas A Beringer J Berry T Bhatti A Binkley M Bisello D Blair RE 《Physical review letters》2006,97(19):191802
We search for excited and exotic muon states mu* using an integrated luminosity of 371 pb(-1) of p[over]p collision data at sqrt[s]=1.96 TeV. We search for associated production of mumu* followed by the decay mu*-->mugamma. We compare the data to model predictions as a function of the mass of the excited muon M(mu*), the compositeness energy scale Lambda, and the gauge coupling factor f. No signal above the standard model expectation is observed. We exclude 107相似文献
202.
The common investment decision rules, Markowitz’s Mean-Variance (MV) rule and the non-parametric Stochastic Dominance (SD)
rules, suffer from one severe drawback: there are pairs of prospects where experimentally 100% of the subjects choose one
prospect, yet these rules are unable to rank the two prospects—a paradoxical result. Thus, the set of all preferences corresponding
to these decision rules is too large, because it contains theoretical preferences that are not encountered in practice. Based
on 400 subjects’ choices we define the economically relevant set of preference and the corresponding new decision rules, which avoid the paradoxical results. The results are very robust
and are almost unaffected by the magnitude of the outcomes and the structure of the prospects under consideration. 相似文献
203.
Sounak Dutta XiaoMeng Sui Haim Weissman Vyacheslav Kalchenko Hanoch Daniel Wagner Boris Rybtchinski 《先进技术聚合物》2019,30(10):2549-2557
We describe a new family of composite materials, polymer/organic nanocrystal (ONC) hybrids. These were prepared from soluble ONCs based on perylene diimides (PDI) and water‐soluble polymers (sodium alginate and polyvinyl alcohol). Polymer/ONC films were characterized by optical spectroscopy, electron microscopy, and tensile strength studies. The films show enhanced chemical and mechanical stability due to synergy between the constituents. The hybrid films are stable in both water and organic solvents, unlike the individual components. The ONCs we employed possess nonlinear optical activity (second harmonic generation, SHG); they showed improved photostability (stable SHG under laser light) in the hybrids. Tensile strength enhancement (as high as twofold in the film having just 2.4% ONCs by weight) was observed as revealed by mechanical measurements. Hybrids with aligned ONCs were also prepared using simple extrusion via syringe needle followed by gelation. Employing ONCs in polymeric hybrid materials enables facile fabrication in aqueous media, synergy, chemical, mechanical, and photostability as well as useful photofunction (SHG), introducing a versatile class of composite materials. 相似文献
204.
A simple qualitative model for hadronic two-body amplitudes is proposed. The model combines the two-component theory of duality with the main idea of the absorption model. The qualitative predictions of the model for elastic differential cross sections and polarizations correctly reproduce several interesting regularities of the data. In particular, the presence of dips in nonexotic elastic processes and their absence in exotic reactions is explained. 相似文献
205.
Isolation and characterisation of novel neutral and cationic Rh(I) complexes having only DMSO molecules as dative ligands give complexes showing S-, O- and bridging S,O-bidentate binding modes of DMSO. 相似文献
206.
Abstract In plants, as in other aerobic organisms, O2 − is a commonly encountered intermediate of oxygen reduction and superoxide dismutases provide a defense against the potential cytotoxicity of this radical. The superoxide dismutases found in plants resemble those encountered in other organisms. Within chloroplasts one finds the CuZn enzyme, while mitochondria contain the Mn enzyme. Nymphaceae, ginkoaceae and cruciferae are unusual among plants, indeed among eukaryotes, in that they contain an iron superoxide dismutase. Bipyridylium herbicides, such as paraquat, exert their effect by diverting electron flow from photosystem I and thus increasing 02 – production. Paraquat-resistant genotypes of horseweed, tobacco and rye grass were found to contain elevated superoxide dismutase. This enzyme also appears to provide a defense against sulfur dioxide, sunscald and photooxidative death. The evidence supporting these statements and possible explanations are discussed. 相似文献
207.
For positive integers t?k?v and λ we define a t-design, denoted Bi[k,λ;v], to be a pair (X,B) where X is a set of points and B is a family, (Bi:i?I), of subsets of X, called blocks, which satisfy the following conditions: (i) |X|=v, the order of the design, (ii) |Bi|=k for each i?I, and (iii) every t-subset of X is contained in precisely λ blocks. The purpose of this paper is to investigate the existence of 3-designs with 3?k?v?32 and λ>0.Wilson has shown that there exists a constant N(t, k, v) such that designs Bt[k,λ;v] exist provided λ>N(t,k,v) and λ satisfies the trivial necessary conditions. We show that N(3,k,v)=0 for most of the cases under consideration and we give a numerical upper bound on N(3, k, v) for all 3?k?v?32. We give explicit constructions for all the designs needed. 相似文献
208.
Multihadron production at high energies proceeds through two mechanisms: A nondiffractive mechanism of a general multiperipheral nature and a diffractive mechanism. Assuming that the diffractive mechanism is dominated at present energies (s < 3000 BeV2) by single diffraction excitation we explore its theoretical and phenomenological implications. In particular we study the question of the rising total cross section. We show that “high mass diffraction excitation” leads to the formation of a central plateau in the inclusive single pion distribution and that the height of this plateau rises with energy and obeys scaling when normalized by the total cross section. We compute the multiplicity distribution for the diffractive component, and deduce the properties of the average multiplicity, its moments, and the statistical mechanics analogue of the “diffractive” Feynman gas. Two-particle correlations are computed and shown to be of a long range nature. Finally we outline an “improved” two component model into which some of the detailed features of the diffractive part are incorporated. 相似文献
209.
Consider the problem: where is a ball on with geodesic radius , and is the Laplace–Beltrami operator on . We prove that for any and any , there exist at least 2k solutions of this problem for λ sufficiently large negative. To cite this article: H. Brezis, L.A. Peletier, C. R. Acad. Sci. Paris, Ser. I 339 (2004). 相似文献
210.
The main result is the following. Let be a bounded Lipschitz domain in , . Then for every with , there exists a solution of the equation div in , satisfying in addition on and the estimate
where depends only on . However one cannot choose depending linearly on .
where depends only on . However one cannot choose depending linearly on .
Our proof is constructive, but nonlinear--which is quite surprising for such an elementary linear PDE. When there is a simpler proof by duality--hence nonconstructive.