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排序方式: 共有193条查询结果,搜索用时 93 毫秒
1.
P. Lugli C. Erlen A. Pecchia F. Brunetti L. Latessa A. Bolognesi G. Csaba G. Scarpa A. di Carlo 《Applied Physics A: Materials Science & Processing》2007,87(3):593-598
Molecular devices have lately attracted increased attention due to some appealing features such as their low production cost,
flexibility in the substrate choice, possibility of large area deployment, and possibly higher integration capabilities. Starting
from a series of results obtained from our groups, we critically review the state-of-the-art in the field of simulation of
organic and molecular systems, by analyzing and comparing existing approaches, and looking at the open problems and possible
solutions and future developments.
PACS 72.80.Le 相似文献
2.
3.
Alagia M Biondini F Brunetti BG Candori P Falcinelli S Moix Teixidor M Pirani F Richter R Stranges S Vecchiocattivi F 《The Journal of chemical physics》2004,121(21):10508-10512
The double photoionization of HCl molecules by synchrotron radiation has been studied in the energy range between 30 and 50 eV. The HCl(2+) and Cl(2+) product ions have been detected by a photoelectron-photoion-coincidence technique, while the H(+)+Cl(+) formation, which follows the double ionization of HCl, has been studied by photoelectron-photoion-photoion coincidence. The photon energy threshold for the production of HCl(2+) ions has been found to be 35.4+/-0.6 eV, while for the dissociative channel leading to H(+)+Cl(+), it has been measured a threshold at 36.4+/-0.6 eV and a change in the slope of the cross-section energy dependence at 38.7+/-0.7 eV. The production of H+Cl(2+) occurs with a threshold photon energy of 42.8+/-1.1 eV. These results appear to be in a good agreement with previous data by different experimental techniques and recent theoretical calculations performed by our laboratory. 相似文献
4.
This work reports the experimental results of the uniaxial pressure dependence at various temperatures of the spin-lattice relaxation time, T1, in paradichlorobenzene single crystals.The directionality of the pressure dependence, together the temperature dependence ot T1 near room temperature, give us some information about the dependence of the molecular torsional frequencies and lifetimes of the oscillations ground levels with the intermolecular crystalline potential. 相似文献
5.
Mono- and bis-(2-hydroxyphenyl)-s-triazines 4 , 14 , 18 , 22 , 28 , 29 can be prepared by (a) reaction of salicylic acid esters 2 with amidines 3 ; (b) reaction of 4H-1, 3-benzoxazin-4-ones 10 with amidines 3 ; and (c) Friedel-Crafts-reaction of chloro-s-triazines 26 , 27 with resorcinol 24 . In case (b) the path of reaction is determined by the character of substituent R4 in 10 . Scope and limitations of these reactions and accessibility of starting materials are discussed. 相似文献
6.
Alves GA Amato S Anjos JC Appel JA Astorga J Bracker SB Cremaldi LM Darling CL Dixon RL Errede D Fenker HC Gay C Green DR Halling AM Jedicke R Karchin PE Kwan S Leuking LH Mantsch PM de Mello Neto JR Metheny J Milburn RH de Miranda JM da Motta Filho H Napier A Passmore D Rafatian A dos Reis AC Ross WR Santoro AF Sheaff M Souza MH Spalding WJ Stoughton C Streetman ME Summers DJ Takach SF Wallace A Wu Z 《Physical review D: Particles and fields》1994,49(9):R4317-R4320
7.
Quantum fields propagating on a curved spacetime are investigated in terms of microlocal analysis. We discuss a condition on the wave front set for the correspondingn-point distributions, called microlocal spectrum condition (SC). On Minkowski space, this condition is satisfied as a consequence of the usual spectrum condition. Based on Radzikowski's determination of the wave front set of the two-point function of a free scalar field, satisfying the Hadamard condition in the Kay and Wald sense, we construct in the second part of this paper all Wick polynomials including the energy-momentum tensor for this field as operator valued distributions on the manifold and prove that they satisfy our microlocal spectrum condition. 相似文献
8.
Alves GA Amato S Anjos JC Appel JA Astorga J Bracker SB Cremaldi LM Dagenhart WD Darling CL Dixon RL Errede D Fenker HC Gay C Green DR Jedicke R Karchin PE Kennedy C Kwan S Lueking LH de Mello Neto JR Metheny J Milburn RH de Miranda JM da Motta Filho H Napier A Passmore D Rafatian A dos Reis AC Ross WR Santoro AF Sheaff M Souza MH Spalding WJ Stoughton C Streetman ME Summers DJ Takach SF Wallace A Wu Z 《Physical review letters》1996,77(12):2388-2391
9.
Alves GA Amato S Anjos JC Appel JA Bracker SB Cremaldi LM Darling CL Dixon RL Errede D Fenker HC Gay C Green DR Jedicke R Kaplan D Karchin PE Kwan S Leedom I Lueking LH Luste GJ Mantsch PM de Mello Neto JR Metheny J Milburn RH de Miranda JM da Motta Filho H Napier A Rafatian A dos Reis AC Reucroft S Ross WR Santoro AF Sheaff M Souza MH Spalding WJ Stoughton C Streetman ME Summers DJ Takach SF Wu Z 《Physical review letters》1993,70(6):722-725
10.
E.?DesimoniEmail author B.?Brunetti R.?Cattaneo 《Accreditation and quality assurance》2004,9(8):445-449
Considering the uncertainty of measurement when assessing compliance with reference values given in compositional specifications and statutory limits is still a controversial matter. In theory, assessing compliance requires considering both type I (false positive) and type II (false negative) errors. The more the concentration of the analyte in the sample under investigation is close to the allowed concentration limit, the more critical it is to consider both types of errors. This paper describes how this could be done. The matter is discussed in the light of the most recent literature information. 相似文献