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991.
The synthesis, physicochemical properties and anodic polymerization of a novel ladder pentaphenylene
Nicolas Cocherel Cyril Poriel Olivier Jeannin Ali Yassin Joëlle Rault-Berthelot 《Dyes and Pigments》2009,83(3):339-347
The synthesis, crystal structure, electrochemical and optical properties of a novel blue emitting ladder pentaphenylene are reported and compared with those of its 3π−2 spiro parent, in order to study the effect of the spiro-linked fluorene rings. Anodic oxidation of the novel compound results via electropolymerization, in the formation of an electroactive material that displays interesting electrochemical and optical properties. 相似文献
992.
Gastrointestinal bleeding caused by erosion of a pancreaticoduodenal artery aneurysm in patients with pancreatitis is a rare but potentially life threatening disease. In this case report, the successful treatment of a patient bleeding from a ruptured pancreaticoduodenal artery aneurysm is described. A review of the literature of reported cases discusses the value of early angiographic intervention in patients with unexplained gastrointestinal hemorrhage and suspected rupture of an aneurysm. 相似文献
993.
Verification of Real-Time Systems using Linear Relation Analysis 总被引:3,自引:2,他引:1
Nicolas Halbwachs Yann-Erick Proy Patrick Roumanoff 《Formal Methods in System Design》1997,11(2):157-185
Linear Relation Analysis [11] is an abstract interpretation devoted to the automatic discovery of invariant linear inequalities among numerical variables of a program. In this paper, we apply such an analysis to the verification of quantitative time properties of two kinds of systems: synchronous programs and linear hybrid systems. 相似文献
994.
The authors are concerned with the comparative analysis of interactive processes in a meeting, subject to various situations of mediation. The research is based on the analysis of records of actual meetings, either in face to face situations, or in audio or video-conferences. Interactivity is first defined as the ability to interrupt in order to help the communication process. The mechanisms which regulate this interactivity are then analyzed, as well as its functions in the way exchanges proceed and speech is built. The thesis is put forward that parallel to the exchange of informations linked to the contents of the meeting, an exchange of control signals, chiefly of an infra and non verbal kind, takes place as on a signalling channel, the role of which is to regulate: the allocation of speech turn-taking, the mutual understanding of participants, the setting out of the speech issued on the main channel, the construction of the common knowledge useful to the achievement of the task, the regulation of speech status, the production of ambiguous and unopposable speeches… The study enables identification of the disturbances brought to the regulation of interactivity when the technical conditions of mediation do change, and allows improvement of the designing of the protocoles aimed at selecting voice and image data before their transmission through teleconferencing systems. 相似文献
995.
Dendrotoxin I (DTX-I) is a 60-residue peptide from the venom of the black mamba snake Dendroaspis polylepis, which binds to neuronal K+ channels. The structure reported previously for DTX-I was synthesized for the first time by a solution procedure. The synthetic product was confirmed to have the correct primary and disulfide structure determined by peptide mapping, sequence analysis and mass measurements. Comparison of synthetic DTX-I with the natural one by high-performance liquid chromatography and capillary zone electrophoresis, as well as by sequence analysis, revealed that the Asn residue at position 12 in the synthetic peptide was Asp in the natural product. Synthesis of DTX-I with Asp at position 12 gave a peptide identical with the natural product in all aspects. NMR analysis of synthetic [Asn12]- and [Asp12]-DTX-I also supported our findings that the Asn residue at position 12 in the DTX-I molecule should be revised as Asp. [Asn12]- and [Asp12]-DTX-I had very similar binding affinities when tested against radiolabeled dendrotoxin binding to rat brain synaptosomal membranes. 相似文献
996.
Régine Gruiec Nicolas Noiret Henri Patin 《Journal of the American Oil Chemists' Society》1995,72(9):1083-1085
Tetrahydro-2-pyranyl ethers from fatty primary alcohols can be converted in a one-step procedure into the corresponding carboxylic
acids in high yields. This process avoids the synthesis of symmetrical esters, particularly for long-chain compounds. This
reaction proved to be useful, for instance, to produce polyunsaturated fatty acids immediately before their biological testing. 相似文献
997.
A new tomographic process measures the spatial phase fractions in slug flow and possesses high positional and temporal resolution. The measuring method is based on the electrical conductivity of the flowing fluids, which is measured between numerous parallel wires. The individual measurements are directly proportional to the relative liquid content. With the aid of an iterative reconstruction procedure they permit calculation of the phase fractions. The quality of reconstruction is improved by consideration of a priori knowledge. The temporal resolution is 0.009 s and the spatial resolution less than 0.1% of the flow cross-section. 相似文献
998.
At the beginning of the 20th century, Alfred Binet sought teaching positions at the Colfte de France and the Sorbonne. Binet wanted to develop experimental psychology in France, but the strong psychopathological orientation of French psychology blocked his ambition. The 1st part of this article relates the history of the introduction of psychology, via Théodule Ribot, to the Sorbonne and the Coll6ge de France. Ribot's premature retirement from the Collège de France in 1901 triggered a battle that led to Binet's repeated failure to gain access to these institutions of higher education and the success in 1902 of Ribot's students: Pierre Janet at the Colfte de France and Georges Dumas at the Sorbonne. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
999.
Doriane Del Frari Sebastien Diliberto Nicolas Stein Clotilde Boulanger Jean-Marie Lecuire 《Journal of Applied Electrochemistry》2006,36(4):449-454
(Bi1-xSbx)2Te3 thermoelectric thin films were deposited on stainless steel discs in 1 M perchloric acid and 0.1 M tartaric acid by pulse electrodeposition in order to optimize the grain growth. The influence of the electrolyte composition,
the cathodic current density and the cathodic pulse time on film stoichiometry were studied. The results show that it is necessary
to increase the Sb content in the electrolyte to obtain the (Bi0.25Sb0.75)2Te3 film stoichiometry. Pulse plating reduced the grain size and the roughness, compared with continuous plating. Thermoelectric
and electrical properties were also studied and it was found that the Seebeck coefficient and electrical resistivity were
related to two parameters: the cathodic pulse current density and the films thickness. 相似文献
1000.
EM Klenova RH Nicolas S U AF Carne RE Lee VV Lobanenkov GH Goodwin 《Canadian Metallurgical Quarterly》1997,25(3):466-474