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471.
D. Elia G. E. Bruno M. Caselle R. A. Fini V. Lenti V. Manzari V. Paticchio R. Santoro G. Anelli M. Burns I. A. Cali M. Campbell S. Ceresa P. Chochula J. Conrad S. Kapusta A. Kluge M. Morel P. Nilsson F. Osmic P. Riedler G. Stefanini C. Torcato de Matos F. Antinori R. Dima D. Fabris M. Lunardon S. Moretto A. Pepato F. Scarlassara G. Segato R. Turrisi G. Viesti A. Badalà F. Librizzi G. S. Pappalardo A. Pulvirenti F. Riggi M. Cinausero E. Fioretto G. Prete L. Vannucci M. Krivda L. Sándor F. Soramel T. Virgili 《Czechoslovak Journal of Physics》2005,55(12):1635-1638
The silicon pixel detector (SPD) comprises the two innermost layers of the inner tracking system oft he ALICE experiment at
LHC. Prototype SPD assemblies have been tested in high-energy proton and pion beams at the CERN SPS. The method used for data
analysis and the most relevant results in relation to detector performance are presented.
Presented in the Poster Session “Future Experiments and Facilities” at the 18th International Conference “Quark Matter 2005”,
Budapest, Hungary, 4–9 August 2005.
On behalf of the Silicon Pixel Detector project in the ALICE Collaboration 相似文献
472.
Mariana Arago Matos Donato Karina Lidianne Alcntara Saraiva Amanda Karolina Soares e Silva Maria Inês Wanderley Christina Alves Peixoto 《Micron (Oxford, England : 1993)》2009,40(8):845-850
Vardenafil citrate is a potent vasodilator used in the treatment of patients with erectile dysfunction. Its mechanism of action is based on the selective inhibition of phosphodiesterase-5 (PDE5), specific to guanosine 3′,5′-cyclic monophosphate (cGMP). Recently, chronic treatment with Vardenafil has been successfully used in cases of pulmonary hypertension and, despite being used in high doses for long periods, little is known about its effects on other systems. In the present study, female mice were treated daily with 5 mg/kg Vardenafil for 4 weeks, after which the ovaries were collected for morphological analyses and sera were collected for biochemical assays. This study found that treatment with Vardenafil decreased HDL serum levels and the number of antral follicles as well as induced lesser lipid content in luteal cells, suggesting that high levels of cGMP may affect follicle development. 相似文献
473.
M. Rodríguez de Rivera F. Socorro J. S. Matos 《Journal of Thermal Analysis and Calorimetry》2008,92(1):79-82
In this paper, it has been carried out a study to analyze the effect of the stirring velocity in the experimental determination
of the mixture enthalpies of several binary mixtures by using a Titration Calorimetric TAM2277-201/2250 by Thermometric AB.
The tested liquid mixtures have been ethanol+water and those containing 1-methyl-2-pyrrolidone and (ethanediol, 1,2-propanediol
or 1,2-butanediol). The stirring aim is to keep the homogeneity in the mixture process, but the stirring velocity must not
be increased in excess in order not to favour the evaporation during the measurement process. This study reveals that every
mixture process shows an optimum stirring velocity. 相似文献
474.
V. H. Rodrigues J. A. Paixão M. M. R. R. Costa A. Matos Beja 《Acta Crystallographica. Section C, Structural Chemistry》2001,57(2):213-215
The title compound, C5H12NO2+·C2HO4−·C5H11NO2 or HC2O4−·(HBET·BET)+ [BET is trimethylglycine (betaine); IUPAC name: 1-carboxy-N,N,N-trimethylmethanaminium hydroxide inner salt], contains pairs of betaine molecules bridged by an H atom, forming dimers linked by a strong hydrogen bond. The hydrogen oxalate anions have a rather unusual star conformation, with an internal torsion angle of 70.1 (4)°. The betaine–betainium dimers are anchored between two zigzag chains of hydrogen oxalate molecules hydrogen bonded head-to-tail running parallel to the b axis. An extended network of C—H⃛O interactions links the anionic chains to the cationic dimers. 相似文献
475.
L. C. Cides da Silva G. L. B. Araújo N. R. Segismundo E. F. Moscardini L. P. Mercuri I. C. Cosentino M. C. A. Fantini J. R. Matos 《Journal of Thermal Analysis and Calorimetry》2009,97(2):701-704
The aim of this study was to use DSC and X-ray diffraction measurements to determine the pore size and pore wall thickness
of highly ordered SBA-15 materials. The DSC curves showed two endothermic events during the heating cycle. These events were
due to the presence of water inside and outside of mesopores. The results of pore radius, wall thickness and pore volume measurements
were in good agreement with the results obtained by nitrogen adsorption measurement, XRD and transmission electron microscopy. 相似文献
476.
Elías Quezada Giovanna Delogu Dolores Viña Lourdes Santana Gianni Podda Maria Joao Matos Carmen Picciau 《Helvetica chimica acta》2009,92(7):1309-1314
Arenofurans have important biological and pharmacological activities. Compared to benzofurans, the reports on the synthesis of benzodifurans are rather limited. Here, we report the synthesis of a linear and an angular 3,3′‐bis(carboxymethyl)substituted benzodifuran and 4′‐carboxymethyl‐substituted angelicins from phloroglucinol, using 4‐halomethyl‐substituted dipyrones as key intermediates in the synthetic route. This strategy shows that the stability of a pyrone ring depends on the type of substituent at C(4) and the conditions used. 相似文献
477.
Yu. Aksyutina H.T. Johansson P. Adrich F. Aksouh T. Aumann K. Boretzky M.J.G. Borge A. Chatillon L.V. Chulkov D. Cortina-Gil U. Datta Pramanik H. Emling C. Forssén H.O.U. Fynbo H. Geissel M. Hellström G. Ickert K.L. Jones B. Jonson A. Kliemkiewicz J.V. Kratz R. Kulessa M. Lantz T. LeBleis A.O. Lindahl K. Mahata M. Matos M. Meister G. Münzenberg T. Nilsson G. Nyman R. Palit M. Pantea S. Paschalis W. Prokopowicz R. Reifarth A. Richter K. Riisager G. Schrieder H. Simon K. Sümmerer O. Tengblad W. Walus H. Weick M.V. Zhukov 《Physics letters. [Part B]》2008
478.
We use a new method of studying the Hurst exponent with time and scale dependency. This new approach allows us to recover the major events affecting worldwide markets (such as the September 11th terrorist attack) and analyze the way those effects propagate through the different scales. The time-scale dependence of the referred measures demonstrates the relevance of entropy measures in distinguishing the several characteristics of market indices: “effects” include early awareness, patterns of evolution as well as comparative behaviour distinctions in emergent/established markets. 相似文献
479.
Clovis Jacinto de Matos 《Physica C: Superconductivity and its Applications》2008,468(3):229-232
The attractive gravitational force between two electrons in superconductors is deduced from the Eddington–Dirac large number relation, together with Beck and Mackey electromagnetic model of vacuum energy in superconductors. This force is estimated to be weaker than the gravitational attraction between two electrons in the vacuum. 相似文献
480.
Joana A. Silva Ana C. Santos Ana T. Marques Manuela Ramos Silva Ana Matos Beja Abílio J. F. N. Sobral 《Journal of chemical crystallography》2008,38(4):301-303
Abstract A new pyrazine compound, has been synthesised and characterised by single-crystal X-ray diffraction: monoclinic, P21/c with a = 11.0707(3) ?, b = 5.23700(10) ?, c = 16.6997(5) ?, β = 103.5385(16)°, Mr = 376.40, V = 941.30(4) ?3, Z = 2. Each molecule possesses C
i
symmetry with the two halves of the molecule related by an inversion centre. C–H···π and C=O···π interactions held the molecules
together.
Index Abstract C–H···π and C=O···π intermolecular interactions in dibenzyl-3,6-dimethylpyrazine-2,5-dicarboxylate
Joana A. Silva, Ana C. Santos, Ana T. Marques, Manuela Ramos Silva, Ana Matos Beja, Abílio J. F. N. Sobrala
In dibenzyl-3,6-dimethylpyrazine-2,5-dicarboxylate, each molecule possesses C
i
symmetry. The molecules are assembled in chains via carbonyl···π interactions.
Electronic supplementary material The online version of this article (doi: ) contains supplementary material, which is available to authorized users. 相似文献