Search results for "angle"
showing 10 items of 1921 documents
Precipitable water vapour content from ESR/SKYNET sun-sky radiometers: validation against GNSS/GPS and AERONET over three different sites in Europe
2018
The estimation of the precipitable water vapour content (W) with high temporal and spatial resolution is of great interest to both meteorological and climatological studies. Several methodologies based on remote sensing techniques have been recently developed in order to obtain accurate and frequent measurements of this atmospheric parameter. Among them, the relative low cost and easy deployment of sun–sky radiometers, or sun photometers, operating in several international networks, allowed the development of automatic estimations of W from these instruments with high temporal resolution. However, the great problem of this methodology is the estimation of the sun-photometric calibration par…
tert-Butyl N-benzyl-N-[4-(4-fluorobenzoylmethyl)-2-pyridyl]carbamate
2008
In the crystal structure of the title compound, C25H25FN2O3, the pyridine ring makes dihedral angles of 75.1 (3), 39.4 (3) and 74.6 (3)° with the phenyl ring, the carbamate plane and the 4-fluorophenyl ring, respectively. The phenyl ring makes dihedral angles of 77.2 (3) and 23.6 (3)° with the carbamate plane and the 4-fluorophenyl ring, respectively. The 4-fluorophenyl ring is perpendicular to the carbamate plane, the dihedral angle between them being 89.5 (3)°.
tert-ButylN-(4-methyl-2-pyridyl)carbamate
2008
The crystal structure of the title compound, C11H16N2O2, contains two crystallographically independent molecules forming dimers by pairs of intermolecular N—H...N hydrogen bonds. The two molecules are related by a pseudo-twofold axis. The dihedral angle between the pyridine ring and the carbamate plane differs in the two molecules [12.1 (3) and 3.5 (3)°].
tert-Butyl N-benzyl-N-(4-methyl-2-pyridyl)carbamate
2008
In the crystal structure of the title compound, C18H22N2O2, the pyridine ring makes dihedral angles of 83.71 (6) and 9.2 (1)° with the phenyl ring and the carbamate plane, respectively. The phenyl ring and the carbamate plane are nearly perpendicular to one another, with a dihedral angle of 87.17 (7)°.
5,11,17,23-Tetra-tert-butyl-25,26,27,28-tetrapentoxycalix[4]arene
2005
The molecule of the title compound, C64H96O4, adopts the typical pinched-cone conformation. The dihedral angles between the reference plane (defined by the C atoms of the methylene bridges) and the benzene rings are 86.88 (4), 136.64 (5), 87.22 (4) and 133.99 (4)°.
Conformation of a chain polyelectrolyte in solution with low molecular weight salt: small angle neutron scattering measurements
1986
Small angle neutron scattering measurements have been carried out on the tetramethylammonium salt of the polystyrenesulfonic acid withDP w =310 and 1060 in water solution with tetramethylammonium chloride with ionic strength between 0.02 M and 1.0 M. The scattering curves in the scattering vector range 0.05 nm−1≤Q≤1.8nm−1 have been fitted using the form factor of a worm-like chain of finite thickness. The conformational parameters mean square radius of gyration, statistic chain element, mass per unit length and mean square radius of the cross-section have been determined experimentally and used for describing the conformation of the coils. By these molecular weights and ionic strengths, exc…
Integrazione di celle fotovoltaiche ibride nel vetromattone
2012
L’invenzione riguarda l’integrazione del vetromattone con celle solari ibride (organiche/inorganiche), conosciute come Dye-sensitized Solar Cell (DSC). La combinazione del vetromattone con le DSC consente di migliorare le prestazioni del prodotto originario rendendolo in grado di produrre energia pulita. Le caratteristiche di trasparenza e isolamento termo-acustico del prodotto possono essere regolate agendo sulla configurazione delle DSC. Il prodotto può essere assemblato a formare pannelli fotovoltaici per la realizzazione di facciate traslucide energeticamente “attive” in varie condizioni luminose (condizioni di luce diffusa o artificiale) e indipendentemente dall’angolo di radiazione so…
Canopy Architecture Appraisal by Fractal Dimension of 'Flordastar' Peach Trees Grafted onto Different Rootstocks
2007
The objective of this research was to evaluate the modification of canopy architecture of ''Flordastar'' peach (Prunus persica L. Batsch) grafted onto rootstocks with different vigour, by the use of fractal dimension (D). The hypothesis was that different vigour rootstocks are able to modify the complexity of the branching pattern and that this effect can be assessed by a geometric parameter such as the fractal dimension (D) of the 2D projection of tree branching structure. The observations were carried out in a four-year-old experimental orchard of cv. ''Flordastar'' peach trees grafted onto Ishtara, Barrier, GF677 and MrS 2/5 rootstocks. On digital pictures of leafless, dormant peach tree…
Universal multipartite d-level entanglement witnesses for realistic measurement settings
2019
Entanglement is an essential resource in quantum information science [1] and its presence in any quantum system can be experimentally detected through entanglement witness operators [2]. In particular, measuring a negative expectation value of a witness with high statistical confidence provides a necessary and sufficient condition to confirm the generation of a genuine multipartite [3] and/or d-level entangled state [4]. In recent years, the experimental generation of complex quantum states has intensified the need for witnesses that are capable of detecting such systems and are experimentally optimal at the same time. This means that the witness should require the least measurement effort …
1,4-Dimethyl-3-phenyl-3H-pyrazolo[3,4-c]isoquinolin-5(4H)-one
2008
The title compound, C18H15N3O, is the product of the thermal decomposition of the diazonium salt derived from 2-amino-N-methyl-N-(3-methyl-1-phenyl-1H-pyrazol-5-yl)benzamide. It is characterized by a trans orientation of the methyl groups with respect to the tricyclic ring system. The molecule has a nearly planar phenylpyrazolo[3,4-c]isoquinolin-5-one system, the largest deviation from the mean plane being 0.066 (2) angstrom for the O atom. The dihedral angle between the phenyl substituent and the heterotricycle is 67 (1)degrees. The packing is stabilized by C-H center dot center dot center dot N hydrogen-bond interactions, with the formation of molecular chains along the c axis.