Search results for "range"
showing 10 items of 4508 documents
Selective favorskii rearrangement in macrocyclic rings
1981
Abstract A mixture of 2,2-dibromo-12-chlorocyclododecanone (IIa) and 2,12-dibromo-2-chlorocyclododecanone (IIb) by Favorskii rearrangement gave selectively methyl 2-chloro-1-cycloundecene-1-carboxylate (IIIa).
Calidad de la farmacoterapia y seguridad de los pacientes en hemodiálisis tratados con estimulantes eritropoyéticos
2008
Objective: To assess an interdisciplinary programme for the improvement of pharmacotherapy quality and patient safety in patients with chronic renal disease who are treated with erythropoiesis-stimulating agents. Method: Observational, longitudinal study. Retrospective analysis (period A) and prospective analysis (period B) following implementation of the programme for haemoglobin values and monthly erythropoiesis- stimulating agent dosage. The proportion of patients with haemoglobin values within the target range (10-5-12.5 g/dl) and those with values above the safety limit (≥ 12.5g/dl) were compared every four months and the average percentage of time with haemoglobin values within the ta…
A Domain Imbedding Method with Distributed Lagrange Multipliers for Acoustic Scattering Problems
2003
The numerical computation of acoustic scattering by bounded twodimensional obstacles is considered. A domain imbedding method with Lagrange multipliers is introduced for the solution of the Helmholtz equation with a second-order absorbing boundary condition. Distributed Lagrange multipliers are used to enforce the Dirichlet boundary condition on the scatterer. The saddle-point problem arising from the conforming finite element discretization is iteratively solved by the GMRES method with a block triangular preconditioner. Numerical experiments are performed with a disc and a semi-open cavity as scatterers.
Orthotrichum consobrinumCardot in Western Europe and South-Western Asia
2009
Abstract Orthotrichum consobrinum Cardot, a moss that was earlier considered an endemic to the Sino-Japanese Region, has been found in the north of the Iberian Peninsula (Spain) and in north-eastern Anatolia (Turkey). Comparison of Spanish and Turkish material with eastern Asiatic specimens revealed no relevant morphological differences, and the specimens from both disjunct populations showed the same range of variation of the species attributes. However, the morphological analysis has revealed some distinctive features of the species that had been overlooked in the past. An updated description of this Euro-Asiatic moss is provided here.
Aircraft wing rock oscillations suppression by simple adaptive control
2020
Abstract Roll angular motion of the modern aircraft operating in non-linear flight modes with a high angle of attack often demonstrates the limit cycle oscillations, which is commonly known as the wing rock phenomenon. Wing rock dynamics are represented by a substantially non-linear model, with parameters varying over a wide range, depending on the flight conditions (altitude, Mach number, payload mass, etc.) and angle of attack. A perspective approach of the wing rock suppression lies in the adaptation methods. In the present paper an application of the simple adaptive control approach with the Implicit Reference Model (IRM) is proposed and numerically studied. The IRM adaptive controller …
1976
The phenomenon of “true cosolvency”, which has only recently been observed in the system acetone/diethyl ether/polystyrene (AC/DEE/PS), is investigated with regard to its pressure dependence and compared with the thermodynamic behaviour of the corresponding binary sub-systems. For the determination of the limits of complete solubility, a pressure apparatus was used which had been constructed, in order to measure the turbidity of fluids in the temperature range of −70 to +500°Cand in the pressure range of 1 to 4000 bar (105 to 4·108 Nm−2). The critical line observed for the system DEE/PS (MPS=20400) looks similar to that reported for AC/PS in the literature, i.e. the upper critical solution …
Synthesis and support composition effects on CH4 partial oxidation over Ni–CeLa oxides
2015
Abstract Two series of Ni (6 wt%) catalysts supported over CeO 2 , La 2 O 3 and mixed CeO 2 –La 2 O 3 were prepared by co-precipitation and by wet-impregnation. The effect of the two Ni loading procedures on the catalyst structural properties was investigated by XRD, TPR and XPS. The catalytic behavior of the catalysts was tested in the methane partial oxidation reaction performed at 1 atm in a temperature range of 400–800 °C using dilute feed gas mixture with CH 4 /O 2 = 2 and gas hourly space velocity of 60,000 ml g −1 h −1 . Total methane combustion was observed within the 450 °C ≤ T ≤ 650 °C temperature range. Above 650 °C partial oxidation of methane started to occur, reaching at 80…
Continuum Monte Carlo simulation of phase transitions in rod-like molecules at surfaces
1994
Stiff rod-like chain molecules with harmonic bond length potentials and trigonometric bond angle potentials are used to model Langmuir monolayers at high densities. One end of the rod-like molecules is strongly bound to a flat two-dimensional substrate which represents the air-water interface. A ground-state analysis is performed which suggests phase transitions between phases with and without collective uniform tilt. Large-scale off-lattice Monte Carlo simulations over a wide temperature range show in addition to the tilting transition the presence of a strongly constrained melting transition at high temperatures. The latter transition appears to be related to two-dimensional melting of th…
Simulations of Array Configurations for the Square Kilometre Array (SKA)
2010
The Square Kilometre Array (SKA) is a new generation radio telescope for the next decades, working at metre to centimetre wavelengths. The SKA will be operational at the same time than other new optical, X-ray and Gamma-ray telescopes. It is of extreme importance that the SKA becomes competitive and complementary to those instruments. An extensive study of technologies and possible configurations involved is needed to ensure the SKA will reach the design specifications. To compare imaging capabilities between different SKA configurations or between the SKA and other instruments, we have implemented figures of merit based on several characteristics of these instruments. In this work we are p…
Crystal structure of bis(cyclohexylammonium) diphenyldioxalatostannate(IV)
2015
In the title salt, (CyNH3)2[Sn(Ph2)(C2O4)2] (Cy is cyclohexyl and Ph is phenyl), the SnPh2 moiety is chelated by two oxalate anions, leading to a cis arrangement within the distorted octahedral coordination sphere of the SnIV atom.