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121.
M. -G. Porquet Ts. Venkova A. Astier I. Deloncle A. Prévost F. Azaiez A. Buta D. Curien O. Dorvaux G. Duchêne B. J. P. Gall F. Khalfallah I. Piqueras M. Rousseau M. Meyer N. Redon O. Stézowski R. Lucas A. Bogachev 《The European Physical Journal A - Hadrons and Nuclei》2006,28(2):153-159
The 87Kr nucleus has been produced as fission fragment in the fusion reaction 18O + 208Pb at 85MeV bombarding energy and studied with the Euroball IV array. High-spin states of this neutron-rich isotope have been
identified for the first time. Its level scheme has been obtained up to 6.3MeV excitation energy and spin I ∼ 23/2ℏ. Its structure is interpreted by analogy with those of the heavier isotones. The proposed configurations involve
both proton and neutron excitations from several sub-shells located close to the Fermi levels, particularly νd5/2, πp3/2f5/2 and πg9/2. Moreover, a revised spin value of 5/2- for the 87Br ground state is proposed. 相似文献
122.
Christina Petschnigg Markus Spitzner Lucas Weitzendorf Jürgen Pilz 《Entropy (Basel, Switzerland)》2021,23(3)
The 3D modelling of indoor environments and the generation of process simulations play an important role in factory and assembly planning. In brownfield planning cases, existing data are often outdated and incomplete especially for older plants, which were mostly planned in 2D. Thus, current environment models cannot be generated directly on the basis of existing data and a holistic approach on how to build such a factory model in a highly automated fashion is mostly non-existent. Major steps in generating an environment model of a production plant include data collection, data pre-processing and object identification as well as pose estimation. In this work, we elaborate on a methodical modelling approach, which starts with the digitalization of large-scale indoor environments and ends with the generation of a static environment or simulation model. The object identification step is realized using a Bayesian neural network capable of point cloud segmentation. We elaborate on the impact of the uncertainty information estimated by a Bayesian segmentation framework on the accuracy of the generated environment model. The steps of data collection and point cloud segmentation as well as the resulting model accuracy are evaluated on a real-world data set collected at the assembly line of a large-scale automotive production plant. The Bayesian segmentation network clearly surpasses the performance of the frequentist baseline and allows us to considerably increase the accuracy of the model placement in a simulation scene. 相似文献
123.
Ftima C. Teixeira Carla Lucas M. Joo M. Curto Antnio P. S. Teixeira M. Teresa Duarte Vnia Andr 《Heteroatom Chemistry》2016,27(1):3-11
Novel tetraethyl ethylene‐1,1‐bisphosphonate esters derived from 1H‐indazole, 1H‐pyrazolo[3,4‐b]pyridine, and 1H‐pyrazolo[3,4‐b]quinoline were synthesized by a Michael addition reaction of tetraethyl ethylidene‐1,1‐bisphosphonate with the corresponding heterocycle, using conventional heating and microwave‐assisted methods. The microwave‐assisted method provides shorter reaction times and better yields. The hydrolysis of bisphosphonates afforded the corresponding bisphosphonic acids or salt, using concentrated hydrochloric acid or TMSBr/collidine, respectively. All new compounds were fully characterized, and their structures were assigned using 1H, 31P, and 13C NMR and IR spectroscopies and mass spectrometry. The molecular structure of compound 6 was confirmed by X‐ray diffraction studies. 相似文献
124.
Validation of Sun Exposure Reported Annually Against Interim Self‐report and Daily Sun Diaries
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Laura King Fan Xiang Ashwin Swaminathan Keith Dear Simone L. Harrison Ingrid van der Mei Michael G. Kimlin Catherine D'Este Robyn M. Lucas 《Photochemistry and photobiology》2017,93(5):1294-1302
Data on personal sun exposure over a period exceeding the immediate past days or weeks are typically self‐reported in brief questionnaire items. The validity of such self‐reporting of longer term personal sun exposure, for example over a year, including detail on variation across seasons, has not previously been investigated. In a volunteer sample (n = 331) of Australian adults aged 18 years and over, we assessed the 12‐month reliability of sun exposure reported separately for each season, and its accuracy compared to a daily sun diary in the same season. Seasonal time outdoors displayed fair‐to‐good reliability between baseline and end of study (12 months), with responses showing higher agreement at lower levels of time outdoors. There was good agreement for ranking of individuals' time outdoors with the daily sun diary data, although the actual diary time outdoors was typically considerably lower than the self‐reported questionnaire data. Place of residence, education, being a smoker, day of the week (i.e. working day vs nonworking day) and working mainly outdoors were significant predictors of agreement. While participants overestimated their actual time outdoors, the self‐report questionnaire provided a valid ranking of long‐term sun exposure against others in the study that was reliable over time. 相似文献
125.
We report the development of a general order relativistic coupled-cluster (CC) code. Our implementation is based on Kramers-paired molecular spinors, utilizes double group symmetry, and is applicable with the full Dirac-Coulomb and several approximate relativistic Hamiltonians. The available methods include iterative and perturbative single-reference CC approaches with arbitrary excitations as well as a state-selective multi-reference CC ansatz. To illustrate the performance of the new code, benchmark calculations have been performed for the total energies, bond lengths, and vibrational frequencies of the monoxides of Group IVa elements. The trends due to the simultaneous inclusion of relativity as well as higher-order electron correlation effects are analyzed. The newly developed code significantly widens the scope of the ab initio relativistic calculations, for both molecules and atoms alike, surpassing the accuracy and reliability of the currently available implementations in the literature. 相似文献
126.
Carlos Camacho-Camacho Maria E. Castillo-Ramos Aurora Vásquez-Badillo Angelina Flores-Parra Rosalinda Contreras 《Journal of organometallic chemistry》2010,695(6):833-9863
The syntheses of [bis(3,5-di-tert-butyl-2-hydroxy-2-phenyl)amine]diphenyltin (1) and [bis(3,5-di-tert-butyl-2-hydroxy-2-phenyl)amine]dichloro-phenyl-stannate (2) by template reactions using 3,5-di-tert-butylcatechol, aqueous ammonia and SnPh2Cl2 are reported. We also report the syntheses of compounds 2, [bis(3,5-di-tert-butyl-2-hydroxy-2-phenyl)amine]trichloro-stannate (4), [bis(3,5-di-tert-butyl-2-hydroxy-2-phenyl)methylamine]chloro-methyltin (5), and [bis(3,5-di-tert-butyl-2-hydroxy-2-phenyl)-n-butylamine]n-butyl-chlorotin (6) and [bis(3,5-di-tert-butyl-2-hydroxy-2-phenyl)amine]n-butyl-dichloro-stannate (7), performed by transmetallation reactions of the octahedral zinc coordination compound Zn[3,5-di-tert-butyl-1,2-quinone-(3,5-di-tert-butyl-2-hydroxy-1-phenyl)imine]2 (3) with SnPhCl3 or SnPh2Cl2, SnCl4, SnMe2Cl2, Sn(nBu)2Cl2 and Sn(nBu)Cl3, respectively. The X-ray diffraction structures of compounds 1, 2, 4 and 6 are reported. The transmetallation reactions with Sn(alkyl)2Cl2 afforded pentacoordinated tin compounds, where an alkyl group migrated from tin to nitrogen, while similar reactions with Sn-Ph compounds did not present any phenyl group migration. 相似文献
127.
José F. Cariñena Javier de Lucas Manuel F. Rañada 《International Journal of Theoretical Physics》2011,50(7):2114-2124
A geometric approach is used to study the Abel first-order differential equation of the first kind. The approach is based
on the recently developed theory of quasi-Lie systems which allows us to characterise some particular examples of integrable
Abel equations. Second order Abel equations will be discussed and the inverse problem of the Lagrangian dynamics is analysed:
the existence of two alternative Lagrangian formulations is proved, both Lagrangians being of a non-natural class. The study
is carried out by means of the Darboux polynomials and Jacobi multipliers. 相似文献
128.
Systems consisting of identical bosons with a large scattering length satisfy universal relations determined by 2-body physics that are similar to those for fermions with two spin states. They require the momentum distribution to have a large-momentum 1/k(4) tail and the radio-frequency transition rate to have a high-frequency 1/ω(3/2) tail, both of which are proportional to the 2-body contact. Identical bosons also satisfy additional universal relations that are determined by 3-body physics and involve the 3-body contact, which measures the probability of 3 particles being very close together. The coefficients of the 3-body contact in the 1/k(5) tail of the momentum distribution and in the 1/ω(2) tail of the radio-frequency transition rate are log-periodic functions of k and ω that depend on the Efimov parameter. 相似文献
129.
Bernard Masereel Mustapha Dinguizli Caroline Bouzin Nicolas Moniotte Olivier Feron Bernard Gallez Thierry Vander Borght Carine Michiels Stéphane Lucas 《Journal of nanoparticle research》2011,13(4):1573-1580
Nanoscale materials are used in the biomedical field for magnetic resonance imaging, protein detection and drug/gene delivery.
Gold nanoparticles (AuNPs) are particularly investigated in cancer treatment and imaging. In this study, we described a simple
and reliable liquid method to coat AuNPs (diameter: 21 nm) layer-by-layer with alternative cationic polyallylamine and anionic
polystyrenesulfonate. The C-terminal amino acid of the antibody directed against anti-bovine serum albumin was activated by
EDC/NHS, and then condensed with the amino functions of the external polyallylamine layer. An ELISA test confirmed that the
antigen recognition of the bioconjugate antibody was conserved. This AuNP coating and the covalently coupling could be used
as a generic process for binding other specific antibodies, particularly those overexpressed in cancer cells and angiogenesis. 相似文献
130.
A. De Maria A. Aurora A. Montone L. Tapfer E. Pesce R. Balboni M. Schwarz C. Borriello 《Journal of nanoparticle research》2011,13(11):6049-6058
Commercially available Sodium clay (Dellite HPS) and organo-clay (Dellite 72T) are modified via a silylation reaction. These
silylated clays are characterized by IR, XRD, thermogravimetric analyses, and their equilibrium contact angles are measured.
They are used to prepare nanocomposites at different loading percentage (1, 3, 5% wt) by in situ intercalative polymerization
of Methyl methacrylate and morphology and thermal properties of nanocomposites are examined. SEM images of nanocomposites
fractured surface show the absence of clays aggregates, confirming a good dispersion and distribution of montmorillonites
in the polymer matrix. The effects of modified clays on the thermal properties of nanocomposites are analyzed by differential
scanning calorimetry and thermogravimetric analyses showing an increase of glass and decomposition temperatures of all nanocomposites
respect to homopolymer ones. The best results are obtained in the presence of silylated montmorillonites, clearly the organosilane
improves the compatibility between polymer matrix and clay and as effect the properties of nanocomposites. 相似文献