Search results for "CONST"
showing 10 items of 7706 documents
2015
This paper provides a commentary on the academic literature on accounting conservatism with a view to highlighting the insights of that literature that are potentially useful for accounting standar...
A Hard X-Ray View of Scorpius X-1 with INTEGRAL : Nonthermal Emission?
2006
We present here simultaneous INTEGRAL/RXTE observations of Sco X-1, and in particular a study of the hard X-ray emission of the source and its correlation with the position in the Z-track of the X-ray color-color diagram. We find that the hard X-ray (above about 30 keV) emission of Sco X-1 is dominated by a power-law component with a photon index of ~3. The flux in the power-law component slightly decreases when the source moves in the color-color diagram in the sense of increasing inferred mass accretion rate from the horizontal branch to the normal branch/flaring branch vertex. It becomes not significantly detectable in the flaring branch, where its flux has decreased by about an order of…
Chromo-Fluorogenic Detection of Nerve-Agent Mimics Using Triggered Cyclization Reactions in Push-Pull Dyes
2010
A family of azo and stilbene derivatives (1-9) are synthesized, and their chromo-fluorogenic behavior in the presence of nerve-agent simulants, diethylchlorophosphate (DCP), diisopropylfluorophosphate (DFP), and diethylcyanophosphate (DCNP) in acetonitrile and mixed solution of water/acetonitrile (3:1 v/v) buffered at pH 5.6 with MES, is investigated. The prepared compounds contain 2-(2-N,N-dimethylaminophenyl)ethanol or 2-[(2-N,N-dimethylamino)phenoxy]ethanol reactive groups, which are part of the conjugated pi-system of the dyes and are able to give acylation reactions with phosphonate substrates followed by a rapid intramolecular N-alkylation. The nerve-agent mimic-triggered cyclization …
Technical Note: Prediction Models of Airborne Sound Insulation of Multilayer Materials with Viscoelastic Thin Sheets
2008
The growing introduction of new insulation materials in building acoustics has caused an increase of the importance of the prediction tools. Appropriate simulations allow strictly necessary laboratory measurements to be identified. In this way, costs are reduced. The demands of new legislation has resulted in the appearance of various software designed to facilitate prediction. The prediction models are based on different hypotheses: adaptation of impedances, spatial behaviour of spectral components, statistical energy distribution, the Finite Element Method (FEM), etc. Each of these models and methods offer advantages and contain limitations. In this paper, different models for prediction…
Complex power distribution analysis in plates covered with passive constrained layer damping patches
2012
International audience; The vibration of a plate partially covered with a passive constrained layer damping (PCLD) patch is studied from an energetic point of view. The damped plate is excited by an acoustic plane wave. The study is done with a numerical two-dimensional multilayer plate model. Results of the present model are compared to those obtained with three-dimensional finite element models. It is shown that the present model gives accurate results, even for the layer's inner behavior. It is less expansive in terms of computational cost; hence, it can simulate efficiently the structure for higher frequencies. Mathematical formulas for complex mechanical power are presented, and the li…
Kinetics and mechanism of group transfer polymerization of N-butyl acrylate catalyzed by Hgl2 /(CH3 )3 Sil in toluene
1994
The group transfer polymerization (GTP) of n-butyl acrylate (nBuA) using 1-methoxy-1-(trimethylsiloxy)-2-methyl-1-propene (MTS) as an initiator, mercuric iodide (HgI2) as a catalyst in toluene at room temperature gives a very good control of molecular weight and narrow molecular weight distribution. (Mw/Mn < 1.2). Kinetic studies in this system reveal that this reaction is rather slow, half-lives being in the range of hours. The kinetic order of the apparent rate constant of propagation with respect to initiator and catalyst concentrations were found to be near to unity. However, the first-order time-conversion plots exhibit considerable induction periods. Upon addition of trimethylsilyl io…
Europa como reto
2006
Data from: Assessing metabolic constraints on the maximum body size of actinopterygians: locomotion energetics of Leedsichthys problematicus (Actinop…
2019
Maximum sizes attained by living actinopterygians are much smaller than those reached by chondrichthyans. Several factors, including the high metabolic requirements of bony fishes, have been proposed as possible body-size constraints but no empirical approaches exist. Remarkably, fossil evidence has rarely been considered despite some extinct actinopterygians reaching sizes comparable to those of the largest living sharks. Here, we have assessed the locomotion energetics of Leedsichthys problematicus, an extinct gigantic suspension-feeder and the largest actinopterygian ever known, shedding light on the metabolic limits of body size in actinopterygians and the possible underlying factors th…
Tinkering with the two-to-one interview: Reflections on the use of two interviewers in qualitative constructionist inquiry
2021
Abstract Typically, qualitative interviews implicate a single interviewer. In this article, we consider an alternative comprising the simultaneous, active involvement of two interviewers. We base our considerations on experiences using the two-to-one interview in a nationwide research project on disability and physical activity. In addition to untapping and developing a qualitative interview method, the article provides an example in action of tinkering in qualitative inquiry. Tinkering entails a constant questioning of what to do, what is best, and what is appropriate within each moment of the research. Echoing social constructionist scholars, we argue that this flexible approach is useful…
Solubility and acid-base properties and activity coefficients of chitosan in different ionic media and at different ionic strengths, at T=25°C
2009
Studies on the acid-base properties and solubility of a polyammonium polyelectrolyte (chitosan) with different molecular weights (MW 310 and 50 kDa), were performed at T=25 °C, in the pH range 2.5–7. The protonation of chitosan was investigated by potentiometry ([H+]-glass electrode) in NaCl, NaNO3 and mixed NaNO3+Na2SO4 ionic media, at different ionic strengths. Protonation constants were calculated as a function of dissociation degree α by means of two different models, namely, a simple linear model and the modified Henderson–Hasselbalch equation. Experimental data were also fitted using a model independent of α (Diprotic-like model), according to which the acid-base properties can be sim…